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1

TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS FROM RADIOPHARMACEUTICALS  

NLE Websites -- All DOE Office Websites (Extended Search)

TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS TABLES OF RADIATION ABSORBED DOSE TO THE EMBRYO/FETUS FROM RADIOPHARMACEUTICALS LATEST REVISION DATE: 1/21/98 The material in this document is taken from the Master's thesis of Ms. Joy Russell (University of Tennessee, Master's Degree conferred August 1995). The data below, and the methods and assumptions used to derive them, are published in two documents in the Health Physics Journal (73(5):747-755, 1997 and 73(5):756-769, 1997) and also in the Proceedings of the Sixth International Radiopharmaceutical Dosimetry Symposium. Please contact the center with any questions or comments about the data. Richard E. Toohey, 423-576-3448 phone, 423-576-8673 fax, tooheyr@orau.gov e-mail Audrey T. Stelson, 423-576-3450 phone, 423-576-8673 fax, stelsona@orau.gov e-mail

2

Solar radiation absorbing material  

DOE Patents (OSTI)

Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

Googin, John M. (Oak Ridge, TN); Schmitt, Charles R. (Oak Ridge, TN); Schreyer, James M. (Oak Ridge, TN); Whitehead, Harlan D. (Clinton, TN)

1977-01-01T23:59:59.000Z

3

Absorbed dose measurements during routine equine radiographic procedures  

E-Print Network (OSTI)

This study was performed in order to determine absorbed doses from scattered radiation to personnel during routine equine radiographic procedures and to determine if the protective apparel adequately reduced exposure from scattered radiation. Absorbed doses were measured for one month at the Texas A&M University Veterinary Teaching Hospital using Li:Mg,Cu,P thermoluminescent dosimeters (TLDs). All personnel present in the x-ray examination room during eqine radiography were monitored using TLDs placed at: (1) the finger level; (2) the waist level; (3) the eye level; and (4) the forearm level. Absorbed doses ranged from 0.693 ligy to 31.3 tigy per study. The greatest doses were associated with the individual handling the cassette holder, although the individual making the exposures received similar doses due to improper techniques. The individual holding the horse's halter consistently received the lowest dose. Although all doses observed were within acceptable limits for occupational workers, results demonstrated the need for protective apparel to effectively reduce exposures.

Salinas, Leticia Lamar

1996-01-01T23:59:59.000Z

4

Radiation dose estimates for radiopharmaceuticals  

SciTech Connect

Tables of radiation dose estimates based on the Cristy-Eckerman adult male phantom are provided for a number of radiopharmaceuticals commonly used in nuclear medicine. Radiation dose estimates are listed for all major source organs, and several other organs of interest. The dose estimates were calculated using the MIRD Technique as implemented in the MIRDOSE3 computer code, developed by the Oak Ridge Institute for Science and Education, Radiation Internal Dose Information Center. In this code, residence times for source organs are used with decay data from the MIRD Radionuclide Data and Decay Schemes to produce estimates of radiation dose to organs of standardized phantoms representing individuals of different ages. The adult male phantom of the Cristy-Eckerman phantom series is different from the MIRD 5, or Reference Man phantom in several aspects, the most important of which is the difference in the masses and absorbed fractions for the active (red) marrow. The absorbed fractions for flow energy photons striking the marrow are also different. Other minor differences exist, but are not likely to significantly affect dose estimates calculated with the two phantoms. Assumptions which support each of the dose estimates appears at the bottom of the table of estimates for a given radiopharmaceutical. In most cases, the model kinetics or organ residence times are explicitly given. The results presented here can easily be extended to include other radiopharmaceuticals or phantoms.

Stabin, M.G.; Stubbs, J.B.; Toohey, R.E. [Oak Ridge Inst. of Science and Education, TN (United States). Radiation Internal Dose Information Center

1996-04-01T23:59:59.000Z

5

Low Dose Radiation Research Program: Glossary  

NLE Websites -- All DOE Office Websites (Extended Search)

Glossary Glossary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z We welcome updates to the glossary. Please send them to Low Dose. A α=β Ratio: A measure of the curvature of the cell survival curve and a measure of the sensitivity of a tissue or tumor to dose fractionation. The dose at which the linear and quadratic components of cell killing are equal. Abscopal Effect: The radiation response in tissue at a distance from the irradiated site invoked by local irradiation. Absorbed Dose Rate: Absorbed dose divided by the time it takes to deliver that dose. High dose rates are usually more damaging to humans and animals than low-dose rates. This is because repair of damage is more efficient when the dose rate is low. Absorbed Dose: The amount of energy deposited in any substance by ionizing

6

Photon Absorbed-Dose-to-Water Primary Standards  

Science Conference Proceedings (OSTI)

Photon Absorbed-Dose-to-Water Primary Standards. ... and scattering/perturbation for the water calorimeter in both Co-60 and high-energy x-ray ...

2013-03-08T23:59:59.000Z

7

Low Dose Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Ancient Salt Beds Ancient Salt Beds Repository Science Renewable Energy The WIPP Underground may be ideal to study effects of Very Low Dose Rates on Biological Systems Low Background Radiation Experiment We're all bathing in it. It's in the food we eat, the water we drink, the soil we tread and even the air we breathe. It's background radiation, it's everywhere and we can't get away from it. But what would happen if you somehow "pulled the plug" on natural background radiation? Would organisms suffer or thrive if they grew up without their constant exposure to background radiation? That's what a consortium of scientists conducting an experiment at the Waste Isolation Pilot Plant aim to find out. Despite being an underground repository for transuranic radioactive waste,

8

Electromagnetic radiation absorbers and modulators comprising polyaniline  

DOE Patents (OSTI)

A composition for absorbing electromagnetic radiation, wherein said electromagnetic radiation possesses a wavelength generally in the range of from about 1000 Angstroms to about 50 meters, wherein said composition comprises a polyaniline composition of the formula ##STR1## where y can be equal to or greater than zero, and R.sup.1 and R.sup.2 are independently selected from the group containing of H, --OCH.sub.3, --CH.sub.3, --F, --Cl, --Br, --I, NR.sup.3 .sub.2, --NHCOR.sup.3, --OH, --O.sup.-, SR.sup.3, --OCOR.sup.3, --NO.sub.2, --COOH, --COOR.sup.3, --COR.sup.3, --CHO, and --CN, where R.sup.3 is a C.sub.1 to C.sub.8 alkyl, aryl or aralkyl group.

Epstein, Arthur J. (Bexley, OH); Ginder, John M. (Columbus, OH); Roe, Mitchell G. (Columbus, OH); Hajiseyedjavadi, Hamid (Columbus, OH)

1992-01-01T23:59:59.000Z

9

Low Dose Radiation Research Program: Slide Shows  

NLE Websites -- All DOE Office Websites (Extended Search)

Dose Health Effects of Radiation Health Effects of Radiation Adaptive Response to Low Dose Radiation PDF Background Radiation PDF Bystander Effects PDF Dirty Bombs PDF DNA Damage...

10

Low Dose Radiation Research Program: Low Dose Radiation Research...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research: Outreach and Resources Authors: Antone L. Brooks and Lezlie A. Couch Institution: Washington State University Tri-Cities, Richland, Washington The...

11

NIST: Comparison of Co60 Absorbed Dose for High-Dose ...  

Science Conference Proceedings (OSTI)

... at the dose levels used in radiation processing were ... 1 to 2 parts in 10 2 . The dose-rate effect ... doses for the laboratories that used low-rate gamma ...

2013-03-13T23:59:59.000Z

12

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

over the southwest summer monsoon region, Meteorol. Atmos.Absorbing aerosols and summer monsoon evolution over SouthK. M. Kim (2006), Asian summer monsoon anomalies induced by

Zhu, Aihua

2010-01-01T23:59:59.000Z

13

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

P.M. Forster (2004), The semi-direct aerosol effect: Impactof absorbing aerosols on marine stratocumulus. Q. J .2005), Global anthropogenic aerosol direct forcing derived

Zhu, Aihua

2010-01-01T23:59:59.000Z

14

Monte Carlo Assessments of Absorbed Doses to the Hands of Radiopharmaceutical Workers Due to Photon Emitters  

SciTech Connect

This paper describes the characterization of radiation doses to the hands of nuclear medicine technicians resulting from the handling of radiopharmaceuticals. Radiation monitoring using ring dosimeters indicates that finger dosimeters that are used to show compliance with applicable regulations may overestimate or underestimate radiation doses to the skin depending on the nature of the particular procedure and the radionuclide being handled. To better understand the parameters governing the absorbed dose distributions, a detailed model of the hands was created and used in Monte Carlo simulations of selected nuclear medicine procedures. Simulations of realistic configurations typical for workers handling radiopharmaceuticals were performedfor a range of energies of the source photons. The lack of charged-particle equilibrium necessitated full photon-electron coupled transport calculations. The results show that the dose to different regions of the fingers can differ substantially from dosimeter readings when dosimeters are located at the base of the finger. We tried to identify consistent patterns that relate the actual dose to the dosimeter readings. These patterns depend on the specific work conditions and can be used to better assess the absorbed dose to different regions of the exposed skin.

Ilas, Dan [ORNL; Eckerman, Keith F [ORNL; Karagiannis, Harriet [ORNL

2009-01-01T23:59:59.000Z

15

Low Dose Radiation Program: Links - General Radiation Information  

NLE Websites -- All DOE Office Websites (Extended Search)

General Radiation Information Answers to Questions about Radiation Dose Ranges Charts - tables showing radiation dose ranges from radio diagnostics to cancer radiotherapy....

16

Low Dose Radiation Program: 2010 Low Dose Radiation Research Program  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research Program Investigators' Workshop Low Dose Radiation Research Program Investigators' Workshop »» Event Slide Show More than 150 people attended this year's workshop, held April 12-14 at the Renaissance M Street Hotel in Washington, D.C. In addition to 34 plenary talks and more than 70 poster presentations made by the program investigators, participants heard guest speakers from the National Cancer Institute and from sister low-dose programs in Europe and Japan. Remarks from DOE Dr. Anna Palmisano, Associate Director, Office of Science, Director for Biological and Environmental Research (BER), welcomed the meeting participants, thanked Low Dose Radiation Research Program Manager Dr. Noelle Metting for her leadership, and acknowledged the importance of the Low Dose Program to DOE because of its unique focus and important role. She

17

SCIENTIFIC CORRESPONDENCE Radiation doses  

E-Print Network (OSTI)

-- ation doses and cancer rates to the workers m the first Soviet atom-bomb facility, near 2 Chelyabinsk-dose groups. Unfortunately, they did not report the number in the workforce. Pending release of the full data' Forschungsergebmsse All (1972). 2.Hunter J. R.. Unesco Reports m Marine Soence 28, (1984). 3. Hassan. E. M. & Hassan

Shlyakhter, Ilya

18

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

resolved Radiative Transfer Model: MODTRAN.131 APMEXModerate Imaging Spectroradiometer MODTRAN MODerate spectralprovide by MODTRAN133 Table 4.2

Zhu, Aihua

2010-01-01T23:59:59.000Z

19

Radiation Leukaemongenesis at Low Doses  

NLE Websites -- All DOE Office Websites (Extended Search)

Leukaemongenesis at Low Doses Leukaemongenesis at Low Doses Simon Bouffler Health Protection Agency Abstract Myeloid leukaemias feature prominently among the cancers associated with human exposures to ionising radiation. The CBA mouse model of radiation-induced acute myeloid leukaemia (AML) has been used extensively for both quantitative and mechanistic studies. Loss of genetic material from chromosome 2 (chr2) is known to be associated with most radiation-induced AMLs. AML develops in CBA mice exposed to X- or γ-radiation, after a mean latency period of 18 months, with a maximal incidence of approximately 25% at 3Gy. A strong candidate AML-suppressor gene located within the commonly deleted region of chr2 has been identified, Sƒpil/PU.1. This gene suffers hemizygous loss and specific

20

Low Dose Radiation Research Program: Aloke Chatterjee  

NLE Websites -- All DOE Office Websites (Extended Search)

Chatterjee, A. and Holley, W.R. 1999 Workshop: Biological Effects of Low-Dose and Low-Dose-Rate Radiation Exposures: An Integrated Theoretical and Experimental Approach....

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Low Dose Radiation Program: Selected Websites  

NLE Websites -- All DOE Office Websites (Extended Search)

The views expressed in these links do not necessarily reflect the view of the Low Dose Radiation Research Program. Scientific Links Agencies with Radiation Regulatory...

22

Low Dose Radiation Research Program: Image Gallery  

NLE Websites -- All DOE Office Websites (Extended Search)

Image Gallery Image Gallery These are images, photographs, and charts presented or developed for Low Dose Radiation Research Investigators’ Meetings. They may be used for presentations or reports. To save, right click on the picture, then choose "Save picture as." U.S. annual per-capita effective radiation dose from various sources for 1980. various sources 1980 Enlarge Image. U.S. annual per-capita effective radiation dose from various sources for 2006. various sources 2006 Enlarge Image. U.S. annual per-capita effective radiation dose from man-made sources in the United States for 2006. man-made 2006 Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience (Rem) Enlarge Image. Ionizing Radiation Dose Ranges showing the wide range of radiation doses that humans experience

23

Low Dose Radiation Program: Links - Organizations Conducting Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Conducting Low Dose Radiation Research Conducting Low Dose Radiation Research DOE Low Dose Radiation Research Program DoReMi Integrating Low Dose Research High Level Expert Group (HLEG) on European Low Dose Risk Research Multidisciplinary European Low Dose Initiative (MELODI) RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiation United States Transuranium & Uranium Registries Organizations Conducting other Radiation Research Argonne National Laboratory (ANL) Armed Forces Radiology Research Institute (AFRRI) Atmospheric Radiation Measurement (ARM) Program Brookhaven National Laboratory (BNL) Center for Devices and Radiological Health (CDRH) Central Research Institute of Electric Power Industry (CRIEPI) Colorado State University Columbia University

24

Low Dose Radiation Program: Radiation Biology and the Radiation Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Biology and the Radiation Research Program Biology and the Radiation Research Program The Department of Energy (DOE) and its predecessor organizations, Energy Research and Development Agency (ERDA) and Atomic Energy Commission (AEC), always have been concerned about the health effects of ionizing radiation. Extensive research has been conducted under their sponsorship at all levels of biological organization from molecules to man. Over the past 60 years, studies using every type of radiation source have included exposure to both external radiation sources and to internally deposited radioactive materials. These exposures used different dose patterns and distributions delivered over a wide range of experimental times. This extensive research provided the basis for the new Low Dose Radiation Research Program, linking

25

Dosimeter for measuring skin dose and more deeply penetrating radiation  

DOE Patents (OSTI)

A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with netruon-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

Jones, Donald E. (Idaho Falls, ID); Parker, DeRay (Idaho Falls, ID); Boren, Paul R. (Idaho Falls, ID)

1981-01-01T23:59:59.000Z

26

ORISE: Radiation Dose Estimates and Other Compendia  

NLE Websites -- All DOE Office Websites (Extended Search)

article addresses methods that can be used to rapidly estimate internal and external radiation dose magnitudes that can be used to help guide early medical management. Included...

27

Low Dose Radiation Research Program: Katherine Vallis  

NLE Websites -- All DOE Office Websites (Extended Search)

Margaret Hospital Newly Funded Project The Characterization of Genetic Responses to Low Dose Radiation Using a Genome-Wide Insertional Mutagensis Approach Technical Abstracts 2005...

28

Low Dose Radiation Research Program: Mohan Natarajan  

NLE Websites -- All DOE Office Websites (Extended Search)

of Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Funded Project Real-Time Molecular Study of Bystander Effect Using...

29

Low Dose Radiation Research Program: Multidimensional Analysis...  

NLE Websites -- All DOE Office Websites (Extended Search)

Multidimensional Analysis of Human Epithelial Cell Response to Low Dose Radiation Mary Helen Barcellos-Hoff Lawrence Berkeley National Laboratory Berkeley, CA. (Jointly funded by...

30

Can radiation therapy treatment planning system accurately predict surface doses in postmastectomy radiation therapy patients?  

Science Conference Proceedings (OSTI)

Skin doses have been an important factor in the dose prescription for breast radiotherapy. Recent advances in radiotherapy treatment techniques, such as intensity-modulated radiation therapy (IMRT) and new treatment schemes such as hypofractionated breast therapy have made the precise determination of the surface dose necessary. Detailed information of the dose at various depths of the skin is also critical in designing new treatment strategies. The purpose of this work was to assess the accuracy of surface dose calculation by a clinically used treatment planning system and those measured by thermoluminescence dosimeters (TLDs) in a customized chest wall phantom. This study involved the construction of a chest wall phantom for skin dose assessment. Seven TLDs were distributed throughout each right chest wall phantom to give adequate representation of measured radiation doses. Point doses from the CMS Xio Registered-Sign treatment planning system (TPS) were calculated for each relevant TLD positions and results correlated. There were no significant difference between measured absorbed dose by TLD and calculated doses by the TPS (p > 0.05 (1-tailed). Dose accuracy of up to 2.21% was found. The deviations from the calculated absorbed doses were overall larger (3.4%) when wedges and bolus were used. 3D radiotherapy TPS is a useful and accurate tool to assess the accuracy of surface dose. Our studies have shown that radiation treatment accuracy expressed as a comparison between calculated doses (by TPS) and measured doses (by TLD dosimetry) can be accurately predicted for tangential treatment of the chest wall after mastectomy.

Wong, Sharon [National University of Singapore, Yong Loo Lin School of Medicine (Singapore); Back, Michael [Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, New South Wales (Australia); Tan, Poh Wee; Lee, Khai Mun; Baggarley, Shaun [National University, Cancer Institute, Department of Radiation Oncology, National University, Hospital, Tower Block (Singapore); Lu, Jaide Jay, E-mail: mdcljj@nus.edu.sg [National University of Singapore, Yong Loo Lin School of Medicine (Singapore); National University, Cancer Institute, Department of Radiation Oncology, National University, Hospital, Tower Block (Singapore)

2012-07-01T23:59:59.000Z

31

Errors and Uncertainties in Dose Reconstruction for Radiation Effects Research  

SciTech Connect

Dose reconstruction for studies of the health effects of ionizing radiation have been carried out for many decades. Major studies have included Japanese bomb survivors, atomic veterans, downwinders of the Nevada Test Site and Hanford, underground uranium miners, and populations of nuclear workers. For such studies to be credible, significant effort must be put into applying the best science to reconstructing unbiased absorbed doses to tissues and organs as a function of time. In many cases, more and more sophisticated dose reconstruction methods have been developed as studies progressed. For the example of the Japanese bomb survivors, the dose surrogate distance from the hypocenter was replaced by slant range, and then by TD65 doses, DS86 doses, and more recently DS02 doses. Over the years, it has become increasingly clear that an equal level of effort must be expended on the quantitative assessment of uncertainty in such doses, and to reducing and managing uncertainty. In this context, this paper reviews difficulties in terminology, explores the nature of Berkson and classical uncertainties in dose reconstruction through examples, and proposes a path forward for Joint Coordinating Committee for Radiation Effects Research (JCCRER) Project 2.4 that requires a reasonably small level of effort for DOSES-2008.

Strom, Daniel J.

2008-04-14T23:59:59.000Z

32

Low Dose Radiation Research Program: About  

NLE Websites -- All DOE Office Websites (Extended Search)

About About Background. Extensive research on the health effects of radiation using standard epidemiological and toxicological approaches has been done for decades to characterize responses of populations and individuals to high radiation doses, and to set exposure standards to protect both the public and the workforce. These standards were set using models that extrapolated from the cancers observed following exposure to high doses of radiation to predicted, but not measurable, changes in cancer frequency at low radiation doses. The use of models was necessary because of our inability to detect changes in cancer incidence following low doses of radiation. Historically, the predominant approach has been the Linear-no-Threshold model (see Wikipedia entry) and collective dose concept that assumes each unit of radiation, no

33

Low Dose Radiation Research Program: Radiation Response in Normal...  

NLE Websites -- All DOE Office Websites (Extended Search)

genes. Using rigorous computational methods, we characterized the dose-dependent, radiation-induced gene expression of HSF-42, a primary cell culture. Our preliminary results...

34

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

NLE Websites -- All DOE Office Websites (Extended Search)

Chronic Low Dose Radiation Effects on Radiation Sensitivity Chronic Low Dose Radiation Effects on Radiation Sensitivity and Chromosome Instability Induction in TK6 Cells Schwartz J.L. 1 , Jordan R. 1 , Slovic J. 1 , Moruzzi A. 1 , Kimmel R. 2 , and Liber, H.L. 3 1 University of Washington, Seattle, WA; 2 Fred Hutchinson Cancer Research Center, Seattle, WA; 3 Colorado State University, Fort Collins, Colorado There are a number of cell responses that can be detected after low dose radiation exposures including the adaptive response, low dose hypersensitivity, and induced genomic instability. The relationship between these different phenomena is unknown. In this study, we measured adaptive responses, low dose hypersensitivity, and induced genomic instability in a human B-lymphoblastoid cell model, TK6, where we could genetically modify radiation responses by either over-expression of BCL-2 or deletion of TP53. TK6

35

Absorbed XFEL Dose in the Components of the LCLS X-Ray Optics  

Science Conference Proceedings (OSTI)

There is great concern that the short, intense XFEL pulse of the LCLS will damage the optics that will be placed into the beam. We have analyzed the extent of the problem by considering the anticipated materials and position of the optical components in the beam path, calculated the absorbed dose as a function of photon energy, and compared these doses with the expected doses required (i) to observe rapid degradation due to thermal fatigue, (ii) to reach the melting temperature, or (iii) to actually melt the material. We list the materials that are anticipated to be placed into the Linac Coherent Light Source (LCLS) x-ray free electron laser (XFEL) beam line, their positions, and the absorbed dose, and compare this dose with anticipated damage thresholds.

Hau-Riege, Stefan

2010-12-03T23:59:59.000Z

36

Low Dose Radiation Program: Workshop VI Abstracts  

NLE Websites -- All DOE Office Websites (Extended Search)

Workshop VI Principal Investigator and Abstracts Workshop VI Principal Investigator and Abstracts Anderson, Carl Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Averbeck, Dietrich Cellular Responses at Low Doses of Ionizing Radiation. Azzam, Edouard Adaptive Responses to Low Dose/Low Dose-Rate ?-Rays in Normal Human Fibroblasts: The Role of Oxidative Metabolism. Bailey, Susan The Role of Telomere Dysfunction in Driving Genomic Instability. Balajee, Adayabalam Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System. Barcellos-Hoff, Mary Helen Imaging Bioinformatics for Mapping Multidimensional Responses. Barcellos-Hoff, Mary Helen Biological Response to Radiation Mediated through the Microenvironment and

37

Low Dose Radiation Research Program: National Laboratories  

NLE Websites -- All DOE Office Websites (Extended Search)

National Laboratories National Laboratories The Low Dose Radiation Program funding encompasses several Scientific Focus Areas (SFAs). The SFAs fund merit-reviewed research at DOE national laboratories. This management approach was created in 2008 by the Office of Biological and Environmental Research (BER) within the U.S. Department of Energy's (DOE's) Office of Science. PNNL's Low Dose Radiation Research Program Scientific Focus Area Linear and Nonlinear Tissue-Signaling Mechanisms in Response to Low Dose and Low Dose-Rate Radiation This program is funded as a U.S. Department of Energy Scientific Focus Area (SFA), and is an integrated cooperative program to understand low dose radiation effects in a complex model system. Coordinating Multidisciplinary Expertise The SFAs are designed to take advantage of the multidisciplinary,

38

Contribution of maternal radionuclide burdens to prenatal radiation doses  

SciTech Connect

This report describes approaches to calculating and expressing radiation doses to the embryo/fetus from internal radionuclides. Information was obtained for selected, occupationally significant radioelements that provide a spectrum of metabolic and dosimetric characteristics. Evaluations are also presented for inhaled inert gases and for selected radiopharmaceuticals. Fractional placental transfer and/or ratios of concentration in the embryo/fetus to that in the woman were calculated for these materials. The ratios were integrated with data from biokinetic transfer models to estimate radioactivity levels in the embryo/fetus as a function of stage of pregnancy and time after entry into the transfer compartment or blood of the pregnant woman. These results are given as tables of deposition and retention in the embryo/fetus as a function of gestational age at exposure and elapsed time following exposure. Methodologies described by MIRD were extended to formalize and describe details for calculating radiation absorbed doses to the embryo/fetus. Calculations were performed using a model situation that assumed a single injection of 1 {mu}Ci into a woman`s blood; independent calculations were performed for administration at successive months of pregnancy. Gestational -stage-dependent dosimetric tabulations are given together with tables of correlations and relationships. Generalized surrogate dose factors and categorizations are provided in the report to provide for use in operational radiological protection situations. These approaches to calculation yield radiation absorbed doses that can be converted to dose equivalent by multiplication by quality factor. Dose equivalent is the most common quantity for stating prenatal dose limits in the United States and is appropriate for the types of effect that are usually associated with prenatal exposure. If it is desired to obtain alternatives for other purposes, this value can be multiplied by appropriate weighting factors.

Sikov, M.R.; Hui, T.E.

1996-05-01T23:59:59.000Z

39

Low Dose Radiation Research Program: Low Dose Radiation Effects in  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation Effects in Differentiating Human Lens Cells Radiation Effects in Differentiating Human Lens Cells E.A. Blakely1, M.P. McNamara1, P.Y. Chang1, K.A. Bjornstad1, D. Sudar1, and A.C. Thompson2 1Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California; 2Advanced Light Source Division, Lawrence Berkeley National Laboratory, Berkeley, California. Introduction The human lens is one of the most radiosensitive organs of the body. Cataract, the opacification of the lens, is a late-appearing response to radiation damage. There are few data available on the late radiation effects of exposure in space flight to charged particle beams, the most prevalent of which are protons. Basic research in this area is needed to integrate the responses of both critical and other representative tissues

40

Influence of Absorbing Aerosols on the Inference of Solar Surface Radiation Budget and Cloud Absorption  

Science Conference Proceedings (OSTI)

This study addresses the impact of absorbing aerosols on the retrieval of the solar surface radiation budget (SSRB) and on the inference of cloud absorption using multiple global datasets. The data pertain to the radiation budgets at the top of ...

Zhanqing Li

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Low Dose Radiation Research Program: Thomas Weber  

NLE Websites -- All DOE Office Websites (Extended Search)

2005 Workshop: A Paracrine Signal Mediates The Cell Transformation Response To Low Dose Gamma Radiation in JB6 Cells. Weber, T.J., Siegel, R.W., Markillie, L.M., Chrisler,...

42

Low Dose Radiation Research Program: Molecular Characterization...  

NLE Websites -- All DOE Office Websites (Extended Search)

the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing Radiation Chaun-Yuan Li Duke University Medical Center Durham, NC Why this Project? To evaluate the roles...

43

Low Dose Radiation Research Program: Micronutrient Deficiency...  

NLE Websites -- All DOE Office Websites (Extended Search)

DNA damage is appreciable and increases with age,3;4 Our aim is to compare low dose radiation with micronutrient deficiency, and endogenous damage by a variety of measures...

44

Low Dose Radiation Research Program: Universities  

NLE Websites -- All DOE Office Websites (Extended Search)

Universities Universities | Duke University | Loma Linda University | Northwestern University | University of Chicago | University of California Davis | Northwestern University University of Chicago University of California Davis Effects of Low Dose Irradiation on NF-κB Signaling Networks and Mitochondria Principal Investigator: Dr. Gayle Woloschak DOE Low Dose Research Program Projects Low dose-low dose rate irradiation leads to long term changes in numbers of mitochondria and mitochondrial genomes - Principal Investigator: Gayle Woloschak, Professor, Department of Radiation Oncology, Northwestern University, Chicago, IL, USA NF-κB-mediated pro-survival network in low dose radiation-induced adaptive protection - Principal Investigator: Jian Jian Li, Professor, Department of Radiation Oncology, University of California Davis, Davis,

45

Radiation Leukaemogenesis at Low Doses  

NLE Websites -- All DOE Office Websites (Extended Search)

myeloid leukaemia development at high and low doses. References 1. Cook WD, McCaw BJ, Herring C, John DL, Foote SJ, Nutt SL and Adams JM (2004). PU.1 is a suppressor of myeloid...

46

Low Dose Radiation Research Program: Research Institutions  

NLE Websites -- All DOE Office Websites (Extended Search)

Institutions Institutions Lovelace Respiratory Research Institute Biological Bases for Radiation Adaptive Responses in the Lung-Lovelace Respiratory Research Institute, Albuquerque, NM USA Contact: Dr. Bobby R. Scott Program Objective Our research focuses on elucidating the biological bases for radiation adaptive responses in the lung and for suppressing lung cancer, and to use the knowledge gained to produce an improved systems-biology-based, risk model for lung cancer induction by low-dose, low linear-energy-transfer (LET) radiation. Research was initiated in October 2009. This research should help foster a new era of low-dose radiation risk/benefit assessment. It will have important implications for possible use of low-dose diagnostic radiation (e.g., X-rays) in cancer therapy. It

47

RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS  

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RADIATION DOSE ESTIMATES TO ADULTS AND CHILDREN FROM VARIOUS RADIOPHARMACEUTICALS Latest Revision Date: 43096 Radiation Internal Dose Information Center Oak Ridge Institute for...

48

Radiation dose from cigarette tobacco  

SciTech Connect

The radioactivity in tobacco leaves collected from 15 different regions of Greece before cigarette production was studied in order to estimate the effective dose from cigarette tobacco due to the naturally occurring primordial radionuclides, such as {sup 226}Ra and {sup 210}Pb of the uranium series and {sup 228}Ra of the thorium series and/or man-made produced radionuclides, such as {sup 137}Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the annual effective dose due to inhalation for adults (smokers) for {sup 226}Ra varied from 42.5 to 178.6 {mu}Sv y{sup -1} (average 79.7 {mu}Sv y{sup -1}), while for {sup 228}Ra from 19.3 to 116.0 {mu}Sv y{sup -1} (average 67.1 {mu}Sv y{sup -1}) and for {sup 210}Pb from 47.0 to 134.9 {mu}Sv y{sup -1} (average 104.7 {mu}Sv y{sup -1}), that is the same order of magnitude for each radionuclide. The sum of the effective dose of the three natural radionuclides varied from 151.9 to 401.3 {mu}Sv y{sup -1} (average 251.5 {mu}Sv y{sup -1}). The annual effective dose from {sup 137}Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv y{sup -1} (average 199.3 nSv y{sup -1})

Papastefanou, C. [Aristotle University of Thessaloniki, Atomic and Nuclear Physics Laboratory, Thessaloniki 54124 (Greece)

2008-08-07T23:59:59.000Z

49

Low Dose Radiation Program: Links - Online Literature  

NLE Websites -- All DOE Office Websites (Extended Search)

Online Literature Online Literature Journals, Books and other Publications Armed Forces Radiobiology Research Institute Chornobyl Center for Nuclear Safety Radioactive Waste and Radioecology "Insight" Magazine Central Research Institute of the Electric Power Industry (CRIEPI) News: Aiming at an information center on low dose radiation research Health Physics International Journal of Radiation Biology Iranian Journal of Radiation Research Journal of Radiological Protection National Council on Radiation Protection and Measurements Radiation Research U.S. Department of Energy (DOE) Information Bridge Reports Animal Cancer Tests and Human Cancer Risk Assessment: A Broad Perspective Effects of Ionizing Radiation: Atomic Bomb Survivors and Their Children (1945-1995) Health Effects of Exposure to Low Levels of Ionizing Radiation: BEIR

50

Radiation Leukemogenesis at Low Dose Rates  

SciTech Connect

The major goals of this program were to study the efficacy of low dose rate radiation exposures for the induction of acute myeloid leukemia (AML) and to characterize the leukemias that are caused by radiation exposures at low dose rate. An irradiator facility was designed and constructed that allows large numbers of mice to be irradiated at low dose rates for protracted periods (up to their life span). To the best of our knowledge this facility is unique in the US and it was subsequently used to study radioprotectors being developed for radiological defense (PLoS One. 7(3), e33044, 2012) and is currently being used to study the role of genetic background in susceptibility to radiation-induced lung cancer. One result of the irradiation was expected; low dose rate exposures are ineffective in inducing AML. However, another result was completely unexpected; the irradiated mice had a very high incidence of hepatocellular carcinoma (HCC), approximately 50%. It was unexpected because acute exposures are ineffective in increasing HCC incidence above background. This is a potential important finding for setting exposure limits because it supports the concept of an ?inverse dose rate effect? for some tumor types. That is, for the development of some tumor types low dose rate exposures carry greater risks than acute exposures.

Weil, Michael; Ullrich, Robert

2013-09-25T23:59:59.000Z

51

Low Dose Radiation Research Program: DOE Lowdose Radiation Program Workshop  

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Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore MD 21201 2 Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland WA 99352 We have recently installed a low LET electron microbeam that generates energetic electrons to mimic radiation damage from gamma and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure including induced genomic instability and

52

Agriculture-related radiation dose calculations  

SciTech Connect

Estimates of radiation dose to the public must be made at each stage in the identification and qualification process leading to siting a high-level nuclear waste repository. Specifically considering the ingestion pathway, this paper examines questions of reliability and adequacy of dose calculations in relation to five stages of data availability (geologic province, region, area, location, and mass balance) and three methods of calculation (population, population/food production, and food production driven). Calculations were done using the model PABLM with data for the Permian and Palo Duro Basins and the Deaf Smith County area. Extra effort expended in gathering agricultural data at succeeding environmental characterization levels does not appear justified, since dose estimates do not differ greatly; that effort would be better spent determining usage of food types that contribute most to the total dose; and that consumption rate and the air dispersion factor are critical to assessment of radiation dose via the ingestion pathway. 17 refs., 9 figs., 32 tabs.

Furr, J.M.; Mayberry, J.J.; Waite, D.A.

1987-10-01T23:59:59.000Z

53

Low Dose Radiation Research Program: Depletion of the Vertebrate...  

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Laboratory, Berkeley, California To better understand the responses to low dose ionizing radiation, we proposed in Aim 1 of our Low Dose grant to use dominant-negative...

54

Low Dose Radiation Research Program Website ?? Highlighting...  

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Website Highlighting Low Dose Research Bill Morgan Pacific Northwest National Laboratory Abstract The Low Dose Radiation Research Programs website is found at http:...

55

Low Dose Radiation Research Program: Genomic Instability and...  

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Genomic Instability and Low Dose Low Dose Rate Radiation. Authors: Lei Huang, Suzanne Grim, William F. Morgan Institutions: University of Maryland. Humans will always receive...

56

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivi...  

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Our research utilizes radiation cataract as a model system to study the effects of low-dose ionizing radiation exposure in a complex, highly differentiated tissue. We believe...

57

Low Dose Radiation Research Program: Low-Dose Dose-Response of  

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Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Low-Dose Dose-Response of Proliferating Human Cells Exposed to Low Dose Rate g-Radiation. Authors: Louise Enns,1 Michael Weinfeld,1 Albert Murtha,1 and Kenneth Bogen2 Institutions: 1Cross Cancer Institute and 2Lawrence Livermore National Laboratory. Clinical and environmental exposure to ionizing radiation rarely exceeds 200 cGy. To examine cell proliferation at early times (up to 5 days) post-irradiation, we are utilizing an assay in which single cells encapsulated within ~30- to 70-µm-diameter agarose gel microdrops (GMDs) are exposed and cultured for 4 days at 37°C, then analyzed by flow cytometry (FC). Clonogenic proliferation is measured as the fraction of occupied GMDs containing multicellular microcolonies after 4 days in culture. This assay was applied to human A549 lung cells exposed to gamma

58

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Abstract Abstract Title: Effects of Low Doses of Radiation on DNA Repair (PNNL Project # 42699) Authors: Eric J. Ackerman, Ph.D. Institutions: Pacific Northwest National Laboratory Richland, WA We developed a functional assay to measure the effects of LDR on repair of many different lesions representative of those found in cells as consequences of normal oxidative metabolism, as well as those caused by radiation. Currently only 1/10th attomole =105 damaged molecules/cell and 3000 cells/measurement are required. We have found that even low doses (10 rad) exert measurable effects on DNA repair. Interestingly, the amount of DNA repair increases at 10-50 rads, plateaus, and then increases even further at higher doses well below doses where radiation-induced lethality

59

Low Dose Radiation Research Program: Effects of Low Doses of Radiation on  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Doses of Radiation on DNA Repair Low Doses of Radiation on DNA Repair Eric Ackerman Pacific Northwest National Laboratory Why this Project? Even low doses (0.1 Gy) exert measurable effects on DNA repair. The first-known oxidative lesion repaired only by nucleotide excision repair found in normal cells is cyclo-dA. This lesion is found in normal cells and thought to be a byproduct of oxidative metabolism. When this lesion occurs, it stimulates repair. If repair is stimulated by low dose radiation, there are some implications for human health. For example, do some individuals exhibit a greater, lower, or no stimulation to certain DNA lesions? If there are population polymorphism that influence DNA repair, then it would be possible to use our assay for screening individuals for repair sensitivity.

60

Thyroid absorbed dose for people at Rongelap, Utirik, and Sifo on March 1, 1954  

Science Conference Proceedings (OSTI)

A study was undertaken to reexamine thyroid absorbed dose estimates for people accidentally exposed to fallout at Rongelap, Sifo, and Utirik Islands from the Pacific weapon test known as Operation Castle BRAVO. The study included: (1) reevaluation of radiochemical analysis, to relate results from pooled urine to intake, retention, and excretion functions; (2) analysis of neutron-irradiation studies of archival soil samples, to estimate areal activities of the iodine isotopes; (3) analysis of source term, weather data, and meteorological functions used in predicting atmospheric diffusion and fallout deposition, to estimate airborne concentrations of the iodine isotopes; and (4) reevaluation of radioactive fallout, which contaminated a Japanese fishing vessel in the vicinity of Rongelap Island on March 1, 1954, to determine fallout components. The conclusions of the acute exposure study were that the population mean thyroid absorbed doses were 21 gray (2100 rad) at Rongelap, 6.7 gray (670 rad) at Sifo, and 2.8 gray (280 rad) at Utirik. The overall thyroid cancer risk we estimated was in agreement with results published on the Japanese exposed at Nagasaki and Hiroshima. We now postulate that the major route for intake of fallout was by direct ingestion of food prepared and consumed outdoors. 66 refs., 13 figs., 25 tabs.

Lessard, E.T.; Miltenberger, R.P.; Conrad, R.A.; Musoline, S.V.; Naidu, J.R.; Moorthy, A.; Schopfer, C.J.

1985-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Functional Proteomic Pattern Identification under Low Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The goal of this study is to explore and to understand the dynamic responses of signaling pathways to low dose ionizing radiation (IR). Low dose radiation (10 cGy or lower) affects several signaling pathways including DNA repair, survival, cell cycle, ... Keywords: low dose radiation, functional proteomics

Young Bun Kim; Jean Gao; Ying Dong; Chin-Rang Yang

2008-11-01T23:59:59.000Z

62

Low Dose Radiation Research Program: Kenneth T. Bogen  

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T. Bogen Lawrence Livermore National Laboratory Technical Abstracts 2002 Workshop: Low-dose dose-response of proliferating human cells exposed to low dose rate g-radiation. Enns,...

63

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Oxidative Stress and Skeletal Health with Low Dose, Ionizing Radiation Globus Ruth NASA Ames Research Center Abstract Osteoporosis profoundly affects the aging U.S. population and exposure to high doses of radiation causes bone loss similar to age-related osteoporosis, although the influence of low dose radiation exposures is not known. The central hypothesis of our DOE project (NASA supplement) is that low doses of radiation modulate subsequent skeletal degeneration via oxidative pathways. Our working hypothesis is that a prior exposure to low dose radiation regulates oxidative metabolism within bone and contributes to bone loss caused either by subsequent high, challenge doses of radiation or by aging. HZE source: Because astronauts are exposed to radiation from GCR and solar

64

Low Dose Radiation Research Program: Low Dose Ionizing Radiation-Induced  

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Low Dose Ionizing Radiation-Induced Effects in Irradiated and Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Authors: B.E. Lehnert, R. Cary, D. Gadbois, and G. Gupta. Institutions: Bioscience Division, Los Alamos National Laboratory. The scientific literature presents a confusing picture concerning health risks due to low dose ionizing radiation (LDIR), e.g., <1-10 cGy. Some effects of LDIR such as enhanced rates of cell proliferation and the induction of radioadaptation may be benign under some circumstances. Other evidence suggests LDIR can be hazardous and that a threshold for potentially detrimental responses, e.g., increases in intracellular reactive oxygen species (ROS), increases in sister chromatid exchanges (SCE), alterations in gene or protein expression profiles, and increased

65

Low Dose Radiation Research Program: Original Research Program Plan  

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Original Research Program Plan Original Research Program Plan Biological Effects of Low Dose and Dose Rate Radiation Prepared for the Office of Biological and Environmental Research by The Low Dose Radiation Research Program Plan Subcommittee of the Biological and Environmental Research Advisory Committee. II. Table of Contents Face Page Table of Contents Executive Summary Introduction Program Outline Low Dose Radiation vs. Endogenous Oxidative Damage - The Same or Different? Key Question Description Decision Making Value Recommendations and Costs Understanding Biological Responses to Radiation And Endogenous Damage Key Question Description Decision Making Value Recommendations and Costs Thresholds for Low Dose Radiation - Fact or Fiction? Key Question Description Decision Making Value Recommendations and Costs

66

Low Dose Radiation Research Program: William F. Morgan  

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William F. Morgan William F. Morgan Pacific Northwest National Laboratory PO Box 999 Richland, Washington About this Project Projects Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells. Genetic Factors Affecting Susceptibility to Low-Dose Radiation Mechanisms of Adaptive Responses and Genomic Instability Induced by Low Dose/ Low Dose Rate Radiation Technical Abstracts 2006 Workshop: Using a Low-LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Sowa, M.B., Goetz, W., Baulch, J., and Morgan, W.F. Genetic Factors Affecting Susceptibility to Low-Dose Radiation

67

Low-Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer  

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Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Dose/Dose-Rate Low-LET Radiation Protects Us from Cancer Bobby R. Scott, Ph.D. and Jennifer D. Di Palma Lovelace Respiratory Research Institute, 2425 Ridgecrest Drive SE Albuquerque, NM 87108 USA Life on earth evolved in a low-level ionizing radiation environment comprised of terrestrial radiation and cosmic rays. Today we all reside in an ionizing radiation environment comprised of both natural background radiation and radiation from human activities (e.g., Chernobyl accident). An evolutionary benefit of the interaction of low-level, low linear-energy-transfer (LET) ionizing radiation with mammalian life forms on earth is adapted protection. Adapted protection involves low-dose/dose-rate, low-LET radiation induced high-fidelity DNA repair in cooperation with normal apoptosis (presumed p53

68

Low Dose Radiation Research Program: Genetic Factors Affecting  

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Affecting Susceptibility to Low-Dose Radiation Affecting Susceptibility to Low-Dose Radiation William F. Morgan Pacific Northwest National Laboratory Why This Project The short-term effects of high doses of ionizing radiation on cellular responses are relatively well understood. Less clear are the long-term consequences of exposure to low dose/low dose-rate radiation and the effects of radiation exposure on the progeny of surviving cells. If a cell survives radiation, it is generally thought to have repaired all the radiation-induced insults and be capable of a "normal healthy life". At a certain frequency, however, we have found that some cells surviving radiation grow normally, but will rearrange their genetic material during time in culture. We call this radiation-induced genomic instability. Many

69

Low Dose Radiation Research Program: Research Program Workshop I Abstracts  

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Genetic Factors Affecting Susceptibility to Low-Dose Radiation Genetic Factors Affecting Susceptibility to Low-Dose Radiation William F. Morgan and John H.J. Petrini Radiation Oncology Research Laboratory, University of Maryland at Baltimore, Baltimore, MD Summary: The goal of our application is to improve the scientific basis for understanding potential risks to the population from low dose radiation exposure based on potential genetic differences that may modulate an individual's sensitivity to low doses of radiation. Abstract: The goal of this application is to improve the scientific basis for understanding potential risks to the population from low dose radiation exposure. We propose to address specific genetic factors that affect individual susceptibility to low dose radiation and ask the question do genetic differences exist that make some individuals more sensitive to

70

Detector Photon Response and Absorbed Dose and Their Applications to Rapid Triage Techniques  

E-Print Network (OSTI)

As radiation specialists, one of our primary objectives in the Navy is protecting people and the environment from the effects of ionizing and non-ionizing radiation. Focusing on radiological dispersal devices (RDD) will provide increased personnel protection as well as optimize emergency response assets for the general public. An attack involving an RDD has been of particular concern because it is intended to spread contamination over a wide area and cause massive panic within the general population. A rapid method of triage will be necessary to segregate the unexposed and slightly exposed from those needing immediate medical treatment. Because of the aerosol dispersal of the radioactive material, inhalation of the radioactive material may be the primary exposure route. The primary radionuclides likely to be used in a RDD attack are Co-60, Cs-137, Ir-192, Sr-90 and Am-241. Through the use of a MAX phantom along with a few Simulink MATLAB programs, a good anthropomorphic phantom was created for use in MCNPX simulations that would provide organ doses from internally deposited radionuclides. Ludlum model 44-9 and 44-2 detectors were used to verify the simulated dose from the MCNPX code. Based on the results, acute dose rate limits were developed for emergency response personnel that would assist in patient triage.

Voss, Shannon Prentice

2008-08-01T23:59:59.000Z

71

Low Dose Radiation Research Program: Bruce E. Lehnert  

NLE Websites -- All DOE Office Websites (Extended Search)

E. Lehnert E. Lehnert Los Alamos National Laboratory Past Project Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated Cells: Pathways Analysis in Support of Risk Assessment. Technical Abstracts 2002 Workshop: Low Dose Ionizing Radiation-Induced Effects in Irradiated and Unirradiated cells: Pathways Analysis in Support of Risk Assessment. Lehnert, B.E., Cary, R., Gadbois, D. and Gupta G. 2001 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. 1999 Workshop: Low Dose, Low Dose Rate Effects of Ionizing Radiation in Irradiated and Unirradiated Cells. Lehnert, B.E. Publications Lehnert, B.E., Radiation bystander effects. U.S.Department of Energy Research News (March 6 issue) Goldberg, Z. and Lehnert, B.E. (2002). Radiation-induced effects in

72

Global methylation responses to low dose radiation exposure  

NLE Websites -- All DOE Office Websites (Extended Search)

methylation responses to low dose radiation exposure methylation responses to low dose radiation exposure Pamela J Sykes, Michelle R Newman, Benjamin J Blyth and Rebecca J Ormsby Haematology and Genetic Pathology, Flinders University and Medical Centre, Flinders Centre for Cancer Prevention and Control, Bedford Park, Adelaide, South Australia 5042 Australia. (pam.sykes@flinders.edu.au). Our goal is to study the mechanisms involved in biological responses to low doses of radiation in vivo in the dose range that is relevant to population and occupational exposures. At high radiation doses, DNA double-strand breaks are considered the critical lesion underlying the initiation of radiation-induced carcinogenesis. However, at the very low radiation doses relevant for the general public, the induction of DNA double-strand breaks

73

Analysis of low dose radiation induced epigenetic modifications...  

NLE Websites -- All DOE Office Websites (Extended Search)

levels ofbiological organization when organisms are exposed to low doses (<0.1Gy) of irradiation.Recent work in determining the exact effects of low dose radiation have shown that...

74

Low Dose Radiation Research Program: Cytogenetic tests of Radiobiologi...  

NLE Websites -- All DOE Office Websites (Extended Search)

relevant low-dose range (less than 0.1 Gy). Relate chromosome damage to radiation-induced cancer. Research Approach By studying molecular mechanisms relevant to low doses and low...

75

Annual report shows potential INL radiation dose well below safe...  

NLE Websites -- All DOE Office Websites (Extended Search)

estimates that the dose from a chest X-ray is about 10 mrem and the dose from cosmic radiation during a 3 hour domestic airline flight is about 1 mrem. Operations at the...

76

Low Dose Radiation Research Program: Proteomic and Biochemical...  

NLE Websites -- All DOE Office Websites (Extended Search)

proteomic changes including protein expression levels and post-translational modification due to low dose-rate ionizing radiation Expected Outcomes Increased differentiation...

77

Low Dose Radiation Research Program: 2011 Current Projects  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains...

78

Low Dose Radiation Research Program: Research Highlights - Ionizing...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Energy Low Dose Radiation Research Program, and the Department of Defense Breast Cancer Research program and Prostate Cancer Research program. Researchers include Eva...

79

Low Dose Radiation Research Program: Assessing Biological Function...  

NLE Websites -- All DOE Office Websites (Extended Search)

Livermore National Laboratory under contract No. W-7405-ENG-48 and funded by the Low Dose Radiation Research Program, Biological and Environmental Research (BER), U.S....

80

Low Dose Radiation Research Program: Genetic Variation in Tissue...  

NLE Websites -- All DOE Office Websites (Extended Search)

Variation in Tissue Responses to Low-dose Radiation Eugene Rinchik Oak Ridge National Laboratory Why this Project? To address how individual genetic background affects tissue...

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Low dose radiation combines with the Src oncoproteinto transform...  

NLE Websites -- All DOE Office Websites (Extended Search)

Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Determine whether low dose radiation exerts persistent epigenetic effects that promote malignancy. Background and...

82

Low Dose Radiation Research Program: Bruce N. Ames  

NLE Websites -- All DOE Office Websites (Extended Search)

University of California, Berkeley Technical Abstracts 2002 Workshop: Comparison of Low-Dose Radiation, Endogenous Oxidants, and Micronutrient Deficiencies through Analyses of DNA...

83

Low Dose Radiation Research Program: Gene Expression Profiles...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Energy by the University of California, Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48 with funding from the DOE Low Dose Radiation Research Program...

84

Low Dose Radiation Research Program: Susan S. Wallace  

NLE Websites -- All DOE Office Websites (Extended Search)

Susan S. Wallace University of Vermont Past Funded Project Free Radical DNA Damage Produced Endogenously and by Low Dose Radiation in Human Cells: Quantitation, Consequences, and...

85

Calculation of radiation therapy dose using all particle Monte Carlo transport  

DOE Patents (OSTI)

The actual radiation dose absorbed in the body is calculated using three-dimensional Monte Carlo transport. Neutrons, protons, deuterons, tritons, helium-3, alpha particles, photons, electrons, and positrons are transported in a completely coupled manner, using this Monte Carlo All-Particle Method (MCAPM). The major elements of the invention include: computer hardware, user description of the patient, description of the radiation source, physical databases, Monte Carlo transport, and output of dose distributions. This facilitated the estimation of dose distributions on a Cartesian grid for neutrons, photons, electrons, positrons, and heavy charged-particles incident on any biological target, with resolutions ranging from microns to centimeters. Calculations can be extended to estimate dose distributions on general-geometry (non-Cartesian) grids for biological and/or non-biological media.

Chandler, William P. (Tracy, CA); Hartmann-Siantar, Christine L. (San Ramon, CA); Rathkopf, James A. (Livermore, CA)

1999-01-01T23:59:59.000Z

86

Systematic measurements of whole-body imaging dose distributions in image-guided radiation therapy  

Science Conference Proceedings (OSTI)

Purpose: The full benefit of the increased precision of contemporary treatment techniques can only be exploited if the accuracy of the patient positioning is guaranteed. Therefore, more and more imaging modalities are used in the process of the patient setup in clinical routine of radiation therapy. The improved accuracy in patient positioning, however, results in additional dose contributions to the integral patient dose. To quantify this, absorbed dose measurements from typical imaging procedures involved in an image-guided radiation therapy treatment were measured in an anthropomorphic phantom for a complete course of treatment. The experimental setup, including the measurement positions in the phantom, was exactly the same as in a preceding study of radiotherapy stray dose measurements. This allows a direct combination of imaging dose distributions with the therapy dose distribution. Methods: Individually calibrated thermoluminescent dosimeters were used to measure absorbed dose in an anthropomorphic phantom at 184 locations. The dose distributions from imaging devices used with treatment machines from the manufacturers Accuray, Elekta, Siemens, and Varian and from computed tomography scanners from GE Healthcare were determined and the resulting effective dose was calculated. The list of investigated imaging techniques consisted of cone beam computed tomography (kilo- and megavoltage), megavoltage fan beam computed tomography, kilo- and megavoltage planar imaging, planning computed tomography with and without gating methods and planar scout views. Results: A conventional 3D planning CT resulted in an effective dose additional to the treatment stray dose of less than 1 mSv outside of the treated volume, whereas a 4D planning CT resulted in a 10 times larger dose. For a daily setup of the patient with two planar kilovoltage images or with a fan beam CT at the TomoTherapy unit, an additional effective dose outside of the treated volume of less than 0.4 mSv and 1.4 mSv was measured, respectively. Using kilovoltage or megavoltage radiation to obtain cone beam computed tomography scans led to an additional dose of 8-46 mSv. For treatment verification images performed once per week using double exposure technique, an additional effective dose of up to 18 mSv was measured. Conclusions: Daily setup imaging using kilovoltage planar images or TomoTherapy megavoltage fan beam CT imaging can be used as a standard procedure in clinical routine. Daily kilovoltage and megavoltage cone beam computed tomography setup imaging should be applied on an individual or indication based protocol. Depending on the imaging scheme applied, image-guided radiation therapy can be administered without increasing the dose outside of the treated volume compared to therapies without image guidance.

Haelg, Roger A.; Besserer, Juergen; Schneider, Uwe [Radiotherapie Hirslanden AG, Institute for Radiotherapy, Aarau 5000 (Switzerland); Vetsuisse Faculty, University of Zurich, Zurich 8057 (Switzerland) and Radiotherapie Hirslanden AG, Institute for Radiotherapy, Aarau 5000 (Switzerland)

2012-12-15T23:59:59.000Z

87

Low Dose Radiation Program: Links - Low Dose Research in Japan...  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Research in Japan-Institutes and Facilities Atomic Bomb Disease Institute, Nagasaki University Institute for Environmental Sciences (IES) National Institute of...

88

Low Dose Radiation Research Program: Linking Molecular Events to Cellular  

NLE Websites -- All DOE Office Websites (Extended Search)

Linking Molecular Events to Cellular Responses at Low Dose Exposures Linking Molecular Events to Cellular Responses at Low Dose Exposures Thomas Weber Pacific Northwest National Laboratory Why This Project It currently costs billions of dollars to protect workers and the public from exposure to man-made radiation, despite exposure levels lower than the natural background levels of radiation. If it could be demonstrated that there is no increased cancer risk associated with these low dose exposures, these resources could be directed toward more critical societal issues. Defining low dose radiation cancer risks is limited by our ability to measure and directly correlate relevant cellular and molecular responses occurring at the low radiation dose and dose rate with tumor formation. This deficiency has led to conservative risk assessments based on low dose

89

Low Dose Radiation Program: Links - Websites about Radiation  

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Websites About Radiation The ABC's of Nuclear Science A Teacher's Guide To The Nuclear Science Wall Chart Answers to Questions about Radiation and You Background Radiation:...

90

Risk equivalent of exposure versus dose of radiation  

SciTech Connect

This report describes a risk analysis study of low-dose irradiation and the resulting biological effects on a cell. The author describes fundamental differences between the effects of high-level exposure (HLE) and low-level exposure (LLE). He stresses that the concept of absorbed dose to an organ is not a dose but a level of effect produced by a particular number of particles. He discusses the confusion between a linear-proportional representation of dose limits and a threshold-curvilinear representation, suggesting that a LLE is a composite of both systems. (TEM)

Bond, V.P.

1986-01-01T23:59:59.000Z

91

IMPRINTED GENES & TRANSPOSITIONS: EPIGENOMIC TARGETS FOR LOW DOSE RADIATION EFFECTS  

Science Conference Proceedings (OSTI)

The overall hypothesis of this grant application is that low dose ionizing radiation (LDIR) elicits adaptive responses in part by causing heritable DNA methylation changes in the epigenome. This novel postulate was tested by determining if the level of DNA methylation at the Agouti viable yellow (A{sup vy}) metastable locus is altered, in a dose-dependent manner, by low dose radiation exposure (radiation hormesis, bringing into question the assumption that every dose of radiation is harmful. Our findings not only have significant implications concerning the mechanism of hormesis, but they also emphasize the potential importance of this phenomenon in determining human risk at low radiation doses. Since the epigenetic regulation of genes varies markedly between species, the effect of LDIR on other epigenetically labile genes (e.g. imprinted genes) in animals and humans needs to be defined.

Randy Jirtle

2012-10-11T23:59:59.000Z

92

Low Dose Radiation Research Program: Induction of Genomic Instability in  

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Induction of Genomic Instability in vivo by Low Doses of 137Cs y Induction of Genomic Instability in vivo by Low Doses of 137Cs y rays, Authors: K. Rithidech1, E.B. Whorton2, M. Tungjai1, E. Ar-Bab1, S.R. Simon1, M. Tawde3 and C.W. Anderson3. Institutions: 1Pathology Department, Stony Brook University, NY 11794-8691, USA, 2University of Texas Medical Branch at Galveston, TX 77550-1047,3Biology Department, Brookhaven National Laboratory, Upton, NY 11973-5000. Information on potential health hazards of radiation at doses below or equal to the level traditionally requiring human radiation protection (less than or equal to 10 cGy) is currently lacking. It is therefore important to characterize early and subsequent in vivo biological response induced by low doses of ionizing radiation because such data should provide information that can help determine whether radiation at this dose level

93

Molecular Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation  

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Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Mechanism Underlying Cellular Adaptive Response to Low Dose Radiation Colette A. Sacksteder § , DJ Black ‡ , Heather Smallwood § , David G. Camp II † , and Thomas C. Squier § § Cell Biology and Biochemistry; † Biological Sciences Division Pacific Northwest National Laboratory, Richland WA 99352 ‡ School of Biological Sciences, University of Missouri, Kansas City MO 64110 The goal of this research is to identify the molecular mechanisms by which cells adapt to low dose radiation exposure. Previously we have shown a radiation dependent increase of Calmodulin (CaM) in RAW 264.7 macrophages (RAW). Therefore we hypothesize that CaM and associated signaling complexes are sensors of low-dose radiation, resulting in alterations in energy metabolism and gene expression. The ultimate experimental goal

94

Low Dose Radiation Program: Links - Organizations Funding Radiation...  

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Funding Radiation Research Australian Radiation Protection and Nuclear Safety Agency Canadian Nuclear Safety Commission Centers for Medical Countermeasures Against Radiological and...

95

Low Dose Radiation Research Program: Transgenerational Effects...  

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Transgenerational Effects of Chronic Low-Dose Irradiation in a Medaka Fish Model System Colorado State University Why this Project? There are major gaps in our knowledge about...

96

Low Dose Radiation Research Program: Research Highlights  

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energy, are the surrounding unirradiated cells also at an increased risk of cancer? Latest Research, Response to Fukushima, Integrating Low Dose into Policy-All Featured at...

97

Low Dose Radiation Research Program: Molecular Characterization of the  

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Molecular Characterization of the Roles of SOD Genes in Mammalian Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li, Zhanjun Guo, Zhonghui Yang, and Eric Chuang Institutions: Dept of Radiation Oncology, Duke University Medical Center, Durham, NC Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland Background The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

98

Low Dose Radiation Research Program: 2003 Molecular Characterization of the  

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Characterization of the Roles of SOD Genes in Mammalian Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Authors: Chuan-Yuan Li,1 Eric Chuang2 Institutions: 1Dept of Radiation Oncology, Duke University Medical Center, Durham, NC, 2Advanced Technology Center, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland The potential risks of exposure to low dose radiation are of major concerns to the DOE/OBER Low Dose Radiation Research Program. It has been long recognized that much of the radiation-induced genetic damage to cells are caused by secondary oxidative species. Therefore, internal cellular defense systems against oxidative stress play significant roles in countering genetic damage induced by ionizing radiation. The role of the detoxifying

99

Health Risks Associated with Low Doses of Radiation  

Science Conference Proceedings (OSTI)

Despite a wealth of information, there remains uncertainty concerning human radiation effects at low dose levels. This report provides background information and a literature review of research on the potential health hazards associated with exposure to low-level ionizing radiation. Topics include radiation characteristics, protection standards, epidemiologic data and risk models, the nature of human health exposure-related effects, important radiation health studies to date, and the scientific method fo...

1994-09-17T23:59:59.000Z

100

Low Dose Radiation Program: Links - Agencies with Radiation Regulatory  

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Agencies with Radiation Regulatory Concerns and Involvement Agencies with Radiation Regulatory Concerns and Involvement Biological Effects of Low Level Exposures (BELLE) Canadian Nuclear Safety Commission Center for Risk Excellence Health Protection Agency The Health Risks of Extraterrestrial Environments International Commission on Radiation Units and Measurements, Inc. International Commission on Radiological Protection (ICRP) International Radiation Protection Association (IRPA) NASA Space Radiation Program National Academy of Sciences (NAS) Nuclear and Radiation Studies Board National Aeronautics and Space Administration (NASA) NASA OBRR Task Book Publication National Council on Radiation Protection (NCRP) National Institute of Environmental Health Sciences (NIEHS) National Toxicology Program (NTP) Occupational Safety and Health Administration (OSHA)

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101

Low Dose Radiation Research Program Publications  

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for medical exposures. Environmental and Molecular Mutagenesis 53(4): 247259 Lynn Hlatky ( 2012) Double-Strand Break Motions Shift Radiation Risk Notions?. PNAS...

102

Low Dose Radiation Program: Principal Program Contacts  

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to the Office of Biological and Environmental Research. Dr. Barcellos-Hoff's current research interests are studies of breast cancer and ionizing radiation. The goal of her...

103

Low Dose Radiation Research Program: Charles Limoli  

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Radiation Biology, University of California, Irvine Funded Project Radiobiology of Neural Cancer Stem Cells Publications Elmore, E., Lao, X.Y., Kapadia, R., Giedzinski, E., Limoli,...

104

Low Dose Radiation Research Program: Characterizing Bystander...  

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To order to investigate these variables for low-linear transfer (LET) radiation, an electron microbeam irradiation system has been developed. An electron source provides a beam...

105

Low Dose Radiation Research Program: Alec Moreley  

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Alec Moreley Technical Abstracts 1999 Workshop: Development of PCR-Based Methods for the Detection of Mutagenic Effects of Ionizing Radiation Morley, A., Turner, D., and Sykes, P....

106

Low Dose Radiation Research Program: Antone (Tony) L. Brooks  

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A.L. and Couch, L.A. 2002 Workshop: Optimizing the Scientific, Regulatory and Social Impact of the DOE Low Dose Radiation Research Program Brooks, A.L., Bull, R.J., and...

107

Low Dose Radiation Research Program: John S. Wassom  

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the Science of the Low Dose Radiation Research Program. Wassom, J.S., Owens, E.T., Martin, S.A., Wolfe, A.K., Lyday, M.K., and Dimmick, S.L. 2001 Workshop: Communicating the...

108

Low Dose Radiation Research Program: Chaun-Yuan Li  

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Chaun-Yuan Li Chaun-Yuan Li Radiation Biology Research, Duke University Medical Center Funded Projects Molecular Characterization of the Role of SOD Genes in Mammalian Cellular Response to Low Dose Ionizing, abstract, description. Technical Abstracts 2006 Workshop: The Roles of Superoxide Dismutage (SOD) in Low Dose Radiation Induced Adaptive Response Yang, Z., Chuang, E., Batinic-Haberle, I., and Li, C.-Y. 2005 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y., Guo, Z., Yang, Z., and Chuang, E. 2003 Workshop: Molecular Characterization of the Roles of SOD Genes in Mammalian Cellular Response to Low Dose Radiation Li, C.-Y. and Chuang, E. Publications Li, F., Sonveaux, P., Rabbani, Z.N., Liu, S., Yan, B., Huang, Q.,

109

Low Dose Radiation Research Program: Research Highlights - Health Physics  

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Health Physics Special Issue Features Contributions by Low Dose Health Physics Special Issue Features Contributions by Low Dose Investigators Health Physics The March 2011 special issue of Health Physics highlights the Victor Bond Workshop held May 2-5, 2010, in Richland, Wash. The workshop honored the late Dr. Victor (Vic) Bond for his lifetime achievement in the radiation sciences. Dr. Bond's research resulted in numerous influential scientific papers that contributed greatly to the understanding of radiation effects in biological systems. The workshop attracted internationally recognized experts in biophysics, experimental radiation biology, epidemiology, and risk assessment to discuss issues of low-dose risk. Participants included current and previously funded U.S. Department of Energy Low Dose Radiation Research

110

Low Dose Radiation Research Program: Mechanisms of Tissue Response...  

NLE Websites -- All DOE Office Websites (Extended Search)

whole body exposure to doses of 0.1 Gy to 5 Gy 60Co-g radiation in liver and mammary gland, which indicate that remodeling is a general and rapid consequence of irradiation but...

111

Low Dose Radiation Research Program: Suresh H. Moolgavkar  

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cohort with low-LET low-dose radiation exposure, and comparison with Japanese atomic bomb survivors. Hazelton, W.D., Krewski, D., Moolgavkar, S.H. 2001 Workshop:...

112

Low Dose Radiation Research Program: Genetic Variation in Tissue...  

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Genetic Variation in Tissue Responses to Low-Dose Radiation Authors: E. M. Rinchik,1,2 P. Hoyt,3 L. Branstetter,1 R. Olszewski,1 K. T. Cain,1 and B. Voy1,3 Institutions: 1Life...

113

Low Dose Radiation Research Program: The Characterization of...  

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The Characterization of Genetic Responses to Low Dose Radiation using a Genome-Wide Insertional Mutagenesis Approach Authors: Katherine A Vallis,1,2,3 William L Stanford,4 Zhuo...

114

Low Dose Radiation Research Program: Comparison of DNA Damage...  

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Comparison of DNA Damage Risk from Low-Dose Radiation and Folate Deficiency Arnold C. Huang,1,2 Chantal Courtemanche,1,2 Nicole Kerry,1,2 Susan T. Mashiyama,1,2 Michael Fenech,3...

115

Low Dose Radiation Research Program: Mechanistic Modeling of...  

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Laboratory Why This Project? Cells that are directly exposed to low doses of ionizing radiation may experience DNA damage. Cells which happen to be in the vicinity of the exposed...

116

Low Dose Radiation Research Program: 2011 Calendar of Upcoming...  

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Ann. Mtg. of the American Roentgen Ray Society, Chicago, IL, USA. May 9-11, 2011 Low Dose Radiation Research Investigators' Workshop, Bethesda, MD, USA. May 16-20, 2011...

117

Low Dose Radiation Research Program: Are Animals Heterozygous...  

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lymphocytes from animals of known genotypes. Radiation-induced foci occur in a time and dose dependent manner in the nuclei of normal cells, NBS cells on the other hand, do not...

118

Low Dose Radiation-Induced Epigenetic Alterations Found in Agouti...  

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Low Dose Radiation-Induced Epigenetic Alterations Found in Agouti Mouse Model Autumn Bernal Autumn Bernal Randy Jirtle Randy Jirtle In a paper published in The FASEB Journal, Low...

119

Low Dose Radiation Research Program: James D. Tucker  

NLE Websites -- All DOE Office Websites (Extended Search)

Role of the Adaptive Response in determining health risks from in vivo exposures to low dose of ionizing radiation Tucker, J. Publications Christian, A.T., Patte, M.S., Attix,...

120

Low Dose Radiation Research Program: The Characterization of...  

NLE Websites -- All DOE Office Websites (Extended Search)

acts as a tag for identification of the gene, by cloning the fusion mRNA and using RT-PCR techniques. We have conducted such a screen using moderate dose radiation (2 to 4 Gy,...

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Low Dose Radiation Research Program: Earlier Events  

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Earlier Events Earlier Events 2000 | 2001 | 2002 | 2003 | 2004 April 2000 Ionizing Radiation Science and Protection in the 21st Century, NCRP, April 5-6, Arlington, VA. RADIATION RESEARCH 2000, Association for Radiation Research, April 10-12, Bristol, UK. Florida Chapter of the Health Physics Society Spring 2000 Meeting, Gainesville, FL, April 13-14. 47th Annual Meeting of the Radiation Research Society, April 29-May 3, Albuquerque, NM. May 2000 IRPA-10 International Congress 2000, May 14-19, Hiroshima, Japan. IRPA-10 Secretariat, c/o Japan Convention Services, Inc., Nippon Press Center Building, 2-2-1, Uchisaiwai-cho, Chiyoda-ku, Tokyo 100, Japan. Phone: 81-3-3508-1214. Fax: 81-3-3508-0820. irpa10@convention.jp. 4th International Non-Ionizing Radiation Workshop, May 22-25, Kyoto,

122

Low Dose Radiation Research Program: Michael Weil  

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Dubrova, Y., Weil, M., and Brenner, D. H2AX Foci after Low Dose-Rate Irradiation Reveal a Defect in DNA DSB Processing in Cells from Unaffected Parents of...

123

Low Dose Radiation Research Program: Mina Bissell  

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Abstracts 2006 Workshop: 3D Tissue Models for the Study of the Effects of Low-Dose Irradiation Nelson, C.M., Fata, J E., Kenny, P.A., and Bissell, M.J. Publications Kumari, I.,...

124

Low Dose Radiation Research Program: David Nelson  

NLE Websites -- All DOE Office Websites (Extended Search)

L.E., Nelson, D., Sorensen, K., Tucker, J.D., and Wyrobek, A.J. (2005). Low-dose irradiation alters the transcript profiles of human lymphoblasoid cells, including genes...

125

Low Dose Radiation Research Program: Genetic Factors Affecting  

NLE Websites -- All DOE Office Websites (Extended Search)

Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Genetic Factors Affecting Susceptibility to Low-Doses of Ionizing Radiation. Authors: William F. Morgan, Pat Concannon & John H.J. Petrini The goal of this program is to test the hypothesis that mice heterozygous for the NBS1 gene are genetically susceptible to low doses of ionizing radiation. Patients with Nijmegen Breakage Syndrome (NBS) are radiation sensitive, because of defects in cellular responses to radiation induced genetic damage. It is unclear whether humans heterozygous for the mutations associated with NBS are radiation sensitive and results from cell culture experiments give conflicting results. In collaboration with John Petrini at the Memorial Sloan Kettering Cancer Center in New York City we developed a mouse model of this disorder and are directly testing the hypothesis

126

Low Dose Radiation Research Program: Melvyn Folkard  

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Melvyn Folkard Melvyn Folkard Gray Cancer Institute About this Project Currently Funded Projects A Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Technical Abstracts 2005 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investiage Mechanisms of the Radiation-Induced Bystander Effect Folkard, M., Vojnovic, B., Schettiono, G., Atkinson, K., Prise, K.M., Michael, B.D. 2003 Workshop: A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation -Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino, G., Atkinson, K., Prise, K.M., Michael, B.D. 2002 Workshop: A Variable-Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Folkard, M., Vojnovic, B., Schettino,

127

Low Dose Radiation Research Program: DOE / NASA Joint Funded Projects  

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DOE/NASA Joint Funded Projects DOE/NASA Joint Funded Projects NASA Source Photo Space explorers are subject to exposure to low dose ionizing radiation. Research that helps determine health risks from this exposure is funded by NASA and DOE. Source: NASA DOE's Low Dose Program and the National Aeronautics and Space Administration (NASA) jointly fund new research to develop a better scientific basis for understanding risks to humans from exposures to low doses or low fluences of ionizing radiation. Research must focus on elucidating molecular mechanisms and pathways involved in normal radiobiological responses to low dose exposure, and must have the potential to ultimately increase understanding of health outcomes from radiation exposures that are at or near current workplace exposure

128

Low Dose Radiation Exposure: Exploring Bystander Effects In Vivo.  

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Exposure: Exploring Bystander Effects Exposure: Exploring Bystander Effects In Vivo. 1 Blyth, B.J., 1 Sykes, P.J. 1 Department of Haematology and Genetic Pathology, Flinders University and Medical Centre, Bedford Park, South Australia, 5042, The general population is daily exposed to chronic, low doses of ionizing radiation from both natural and artificial sources. The shape of the radiation dose-response curve at these low doses is currently linearly extrapolated from data obtained after high dose exposure due to the low sensitivity of traditional biological assays after near-background exposures. At odds with this Linear No-Threshold model, are the phenomena collectively referred to as the radiation-induced bystander effect. The bystander effect describes a collection of in vitro

129

Low Dose Radiation Program: Workshops, Proceedings, Abstracts and Programs  

NLE Websites -- All DOE Office Websites (Extended Search)

Workshops, Proceedings, Abstracts and Programs Workshops, Proceedings, Abstracts and Programs UPDATE: Investigators' Workshop Postponed The annual Low Dose Radiation Research Program Investigators' Workshop typically held in April or May has been postponed until next year. Please keep checking the website for updates. 2010 The 2010 DOE Low Dose Radiation Research Investigators' Workshop was held April 12-14, 2010, at the Renaissance M Street Hotel in Washington, D.C. In addition to 34 plenary talks and more than 70 poster presentations made by the program investigators, participants heard guest speakers from the National Cancer Institute and from sister low-dose programs in Europe and Japan. See link for investigators' abstracts. 2009 The DOE Low Dose Radiation Research Investigators' Workshop VIII was held

130

Low Dose Radiation Program: Links - Research Societies with Radiation...  

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Societies with Radiation Concerns Academy of Radiology Research American Association of Physicists in Medicine American Nuclear Society American Roentgen Ray Society American...

131

Low Dose Radiation Research Program: Marianne B. Sowa  

NLE Websites -- All DOE Office Websites (Extended Search)

Marianne B. Sowa Marianne B. Sowa PNNL - Pacific Northwest National Laboratory Funded Projects A Mechanistic Study of the Radiation Quality Dependence of Bystander Effects in Human Cells Technical Abstracts 2006 Workshop: Using a Low-LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation. Sowa, M.B., Goetz, W., Baulch, J., and Morgan, W.F. Morphological Changes in a 3D Mammary Model Following Exposure to Low Dose, Low-LET Radiation Opresko, L.K., Chrisler, W., Emory, K., Arthurs, B., and Sowa, M.B. 2005 Workshops: Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Morgan, W.F. and Sowa, M.B. Publications Perrine, K.A., Lamarche, B.L., Hopkins, D.F., Budge, S.E., Opresko, L.K., Wiley, H.S., and Sowa, M.B. (2007). High speed method for in situ

132

Low Dose Radiation Research Program: Current Funded Project Descriptions  

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Funded Project Descriptions Funded Project Descriptions Effects Of Low Doses of Radiation on DNA Repair Jointly funded by NASA and DOE Eric J Ackerman Pacific Northwest National Laboratory Richland, WA 99352 Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

133

Low Dose Radiation Research Program: Project Descriptions-Archive  

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Project Descriptions-Archive Project Descriptions-Archive Effects Of Low Doses of Radiation on DNA Repair Eric J Ackerman (former PNNL) (Jointly funded by NASA and DOE) Pacific Northwest National Laboratory Richland, WA Dr. Ackerman will study the effect of low doses of ionizing radiation on the repair of different types of damage to DNA, including damage from ionizing radiation and that produced by the normal internal operation of the cell. Using a very sensitive technique called host cell reactivation assay (HCR), he will quantitatively measure the repair of each type of DNA damage and thereby measure if the cellular repair system itself has been damaged. He will also determine if unique forms of DNA repair system damage are induced by low doses of cosmic radiation exposure present during space

134

Low dose radiation combines with the Src oncoprotein to transform  

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radiation combines with the Src oncoprotein to transform radiation combines with the Src oncoprotein to transform pre-malignant human breast cells Paul Yaswen Lawrence Berkeley National Laboratory Abstract Goal: Determine whether low dose radiation exerts persistent epigenetic effects that promote malignancy. Background and Significance: Some persistent carcinogenic effects of radiation may not be traceable to specific DNA sequence alterations and may not be linearly related to dose. Through the biochemical initiation of positive feedback loops, ionization-induced events may have heritable non-linear effects on cellular behavior. Inflammatory responses involving the transcription factor NFκB may be subject to such effects. Increased NFκB activity has been strongly linked to carcinogenesis in a number of published in vitro and in vivo studies (reviewed in [1]). Since radiation

135

Low Dose Radiation Research Program: What's New Archive  

NLE Websites -- All DOE Office Websites (Extended Search)

What's New What's New Tony Brooks Chosen As Lauriston S. Taylor Lecturer Congratulations to radiation biologist Dr. Antone "Tony" Brooks, a consultant to the Pacific Northwest National Laboratory's Low Dose Radiation Research Program, on his selection to give the 36th Lauriston S. Taylor Lecture at the Annual Meeting of the National Council on Radiation Protection and Measurements (NCRP). Brooks is former chief scientist for the U.S. Department of Energy's Low Dose Radiation Research Program. His lecture, titled "From the Field to the Laboratory and Back: The What Ifs, Wows, and Who Cares of Radiation Biology," will be a featured presentation at the meeting, which will be held March 12 and 13, 2012, at the Hyatt Regency Bethesda, Bethesda, Maryland.

136

Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells  

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Low Dose Radiation Research Program: Low Dose Response of Respiratory Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells in Intact Tissues and Reconstituted Tissue Constructs Authors: John Ford, Amy Maslowski, Alex Redd and Les Braby Institutions: Texas A&M University, College Station, TX We are developing a model of respiratory tissue using a perfusion culture system. We are using this system to quantify the effects of normal tissue architecture, and the interaction of epithelial cells with other cell types, on radiation-induced bystander effects. Tracheal tissue taken from young adult Fischer 344 rats is imbedded in a growth factor enriched agarose matrix. The chamber is designed to allow growth medium to periodically wash the epithelial surface of the tracheal lumen while maintaining the air-interface that is necessary for the normal

137

Estimation of radiation doses for atomic-bomb survivors in the Hiroshima University Registry  

Science Conference Proceedings (OSTI)

The present study presents the Hiroshima University Registry of atomic bomb survivors, of which the total number is about 270,000, and application of absorbed doses. From this registry, we picked up 49,102 survivors and applied organ doses based on the dosimetry system 1986 (DS86), which is named the Atomic Bomb Survivor 1993 Dose (ABS93D). The applied dose data are based on the tables listed in the DS86 final report such as the free-in-air kermas, the house shielding factors, and organ dose factors for the active bone marrow and the breast. Calculations for the 13 other organs provided in DS86 are possible. To obtained the organ doses for each survivor, it is necessary to obtain information concerning (1) place exposed, (2) whether they were shielded or not, and (3) age. ABS93D body transmission factors for active bone marrow for neutrons and gamma rays agreed with DS 86 to within a few percent. Of the survivors studied, 35, 123 of them were used for the relative risk estimation of leukemia mortality, adopting the same method as the Radiation Effects Research Foundation (RERF) for comparison. For the observation period from 1968 to 1989, the analyzed relative risks for leukemia mortality at 1 Gy by shielded kerm and by active bone marrow dose are 2.01 and 2.37, respectively, which are consistent with the RERF results. 11 refs., 1 fig., 3 tabs.

Hoshi, M.; Matsuura, M.; Hayakawa, N.; Kamada, N. [Hiroshima Univ., Kasumi (Japan); Ito, C. [Hiroshima A-bomb Casualty Council Health Management Promotion Center, Senda-machi Naka-ku (Japan)

1996-05-01T23:59:59.000Z

138

Effective dose and several factors of its identification. (Assessment of radiation hazard in space flights)  

E-Print Network (OSTI)

Effective dose and several factors of its identification. (Assessment of radiation hazard in space flights)

Farber, Yu V; Grigoriev, Yu G; Tabakova, L A

1971-01-01T23:59:59.000Z

139

Low Dose Radiation Research Program: Do Heritable Differences in an  

NLE Websites -- All DOE Office Websites (Extended Search)

Do Heritable Differences in an Individual's Immune System Predict Do Heritable Differences in an Individual's Immune System Predict Differential Sensitivity to Low Dose Radiation Exposure? Quantitative trait loci (QTL) mapping Enlarge Image Quantitative trait loci (QTL) mapping identifies two strong candidate genes, Ptprk (Chr 10) and Acp1 (Chr 12) that are linked to genetic variation in the relative abundance of peripheral Th and Tc cells, two cell populations that are sensitive to radiation exposure at low doses. Expression of each gene is significantly altered by exposure to low dose radiation in vivo. Genome-wide scans for the ratio of %CD4+ (Th) to %CD8+ (Tc) lymphocytes were performed using genenetwork.org. The solid horizontal line represents genome-wide significance at P < 0.05, based on 1,000 permutations. LOD indicates logarithm of odds scores.

140

Persistent DNA damage foci, cellular senescence and low dose radiation  

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Persistent DNA damage foci, cellular senescence and low dose radiation Persistent DNA damage foci, cellular senescence and low dose radiation Denise Munoz 1 , Albert Davalos 1 , Francis Rodier 1 , Misako Kawahara 1 , Judith Campisi 1,2 and Steven Yannone 1,3 1 Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Mailstop 84-171, Berkeley CA 94720; 2 Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945; 3 Corresponding author Ionizing radiation (IR) induced DNA double-strand breaks (DSBs) are cytologically detectable as large nuclear foci that contain phosphorylated histone H2AX (γH2AX), the adaptor protein 53BP1, and several other proteins that participate in the sensing and processing of DNA damage (DNA damage foci). In normal human cells, moderately high IR (0.5-1 Gy) doses cause the rapid appearance of these foci (acute DNA damage foci), which gradually disappear

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Low Dose Radiation Research Program: Biologically Based Analysis of Lung  

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Biologically Based Analysis of Lung Cancer Incidence in a Large Biologically Based Analysis of Lung Cancer Incidence in a Large Canadian Occupational Cohort with Low-LET Low-dose Radiation Exposure, and Comparison with Japanese Atomic Bomb Survivors. Authors: W.D. Hazelton, D. Krewski, S.H. Moolgavkar Lung cancer incidence is analyzed in a large Canadian National Dose Registry (CNDR) cohort with individual annual dosimetry for low-dose occupational exposure to gamma and tritium radiation using several types of multistage models. The primary analysis utilizes the two-stage clonal expansion model (TSCE), with sensitivity analyses using extensions of this model incorporating additional stages. Characteristic and distinct temporal patterns of risk are found for dose-response affecting early, middle, or late stages of carcinogenesis, e.g., initiation with one or more stages,

142

Low Dose Radiation Research Program: Frequencies of Radiation-Induced  

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Frequencies of Radiation-Induced Chromosome Interchanges and Frequencies of Radiation-Induced Chromosome Interchanges and Randomness of Chromosome Territory Locations Relative to One Another. Authors: RK Sachs,§ MN Cornforth,‡ KM Greulich-Bode,* L Hlatky, and DJ Brenner|| Institutions: §Department of Mathematics, University of California, ‡University of Texas Medical Branch, *Department of Skin Carcinogenesis, German Cancer Research Center DFCI, Harvard Medical School, ||Center for Radiological Research, Columbia University. Leukemogenesis, and perhaps carcinogenesis in general, often involves specific chromosome translocations. Radiation-induced chromosome translocation frequencies are strongly influenced by how close participating chromosomes are to one another in an interphase cell nucleus. We sought to determine whether chromosomes in human peripheral blood

143

Low Dose Radiation Research Program: Adaptive Response of Mouse Skin  

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Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1 Authors: Jian Jian Li, Kazi M. Ahmed, Ming Fan, Shaozhong Dong, Douglas R. Spitz, and Cheng-Rong Yu Institutions: Division of Molecular Radiobiology, Purdue University School of Health Sciences, West Lafayette, Indiana; Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, Iowa; Molecular Immunology Section, Laboratory of Immunology, National Eye Institute, National Institutes of Health, Bethesda, Maryland Gene expression profiles demonstrate that a group of key stress-responsive genes are associated with radiation exposure and may contribute to cellular

144

Low Dose Radiation Research Program: Molecular Mechanisms of  

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Molecular Mechanisms of Radiation-Induced Genomic Instability in Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Authors: Howard L. Liber1 and Jeffrey L. Schwartz2. Institutions: 1Colorado State University and 2University of Washington. Knowledge of the signal and target through which radiation induces genomic instability, which we propose to investigate herein, will allow us to model effects at low doses. Such knowledge will aid in understanding variations in the induction of this genomic instability, both among cells and among individuals. This information could also lead to more sensitive measures of instability that could yield accurate measures of instability induction at low doses. We have developed an in-vitro cell model, in which radiation-induced chromosome instability develops in a two-stage process.

145

Low Dose Radiation Research Program: Molecular Characterization of Survival  

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Survival Advantage, Bystander Effect, and Survival Advantage, Bystander Effect, and Genomic Instability after Low-LET Low Dose Radiation Exposure Mohan Natarajan University of Texas Health Science Center Why this Project? To understand the molecular link between the activation of NF-kB and cellular outcomes such as better cell survival after low-LET radiation and to determine whether low dose radiation-induced NF-kB signaling can mediate telomerase activation and thus confer enhanced cell survival of normal aortic endothelial cells. Project Goals To determine whether low-linear energy transfer (LET) radiation can cause a positive feedback signal initiated by the activation of the NF-kB. To examine one of the mechanisms involving TNF-a as a signaling mediator, which could mediate the bystander effect through the generation

146

Low Dose Radiation Research Program: Janet E. Baulch  

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Janet E. Baulch Janet E. Baulch University of California, Davis Currently Funded Projects Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Technical Abstracts 2003 Workshop: DNA damage in acutely irradiated F2 mice with a history of paternal F0 germline irradiation Baulch, J.E. and Raabe, O G. 2002 Workshop Impact of Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation, Baulch, J.E., Ph.D. and Raabe, O.G., Ph.D. Publications Kovalchuk, O. and Baulch, J.E. (2008). Epigenetic changes and nontargeted radiation effects - Is there a link? Environmental and Molecular Mutagenesis 49(1):16-25 Laiakis, E.C., Baulch, J.E., and Morgan, W.F. (2008). Interleukin 8 exhibits a pro-mitogenic and pro-survival role in radiation induced

147

An evaluation of theories concerning the health effects of low-dose radiation exposures  

E-Print Network (OSTI)

The danger of high, acute doses of radiation is well documented, but the effects of low-dose radiation below 100 mSv is still heavily debated. Four theories concerning the effects of lowdose radiation are presented here: ...

Wei, Elizabeth J. (Elizabeth Jay)

2012-01-01T23:59:59.000Z

148

Reducing Stray Radiation Dose for a Pediatric Patient Receiving Proton Craniospinal Irradiation  

Science Conference Proceedings (OSTI)

Dose/Dose Rate / Special Issue on the 11th International Conference on Radiation Shielding and the 15th Topical Meeting of the Radiation Protection and Shielding Division (Part 1) / Radiation Protection

Phillip J. Taddei; Dragan Mirkovic; Jonas D. Fontenot; Annelise Giebeler; Yuanshui Zheng; Uwe Titt; Shiao Woo; Wayne D. Newhauser

149

Systematic measurements of whole-body dose distributions for various treatment machines and delivery techniques in radiation therapy  

Science Conference Proceedings (OSTI)

Purpose: Contemporary radiotherapy treatment techniques, such as intensity-modulated radiation therapy and volumetric modulated arc therapy, could increase the radiation-induced malignancies because of the increased beam-on time, i.e., number of monitor units needed to deliver the same dose to the target and the larger volume irradiated with low doses. In this study, whole-body dose distributions from typical radiotherapy patient plans using different treatment techniques and therapy machines were measured using the same measurement setup and irradiation intention. Methods: Individually calibrated thermoluminescent dosimeters were used to measure absorbed dose in an anthropomorphic phantom at 184 locations. The dose distributions from 6 MV beams were compared in terms of treatment technique (3D-conformal, intensity-modulated radiation therapy, volumetric modulated arc therapy, helical TomoTherapy, stereotactic radiotherapy, hard wedges, and flattening filter-free radiotherapy) and therapy machine (Elekta, Siemens and Varian linear accelerators, Accuray CyberKnife and TomoTherapy). Results: Close to the target, the doses from intensity-modulated treatments (including flattening filter-free) were below the dose from a static treatment plan, whereas the CyberKnife showed a larger dose by a factor of two. Far away from the treatment field, the dose from intensity-modulated treatments showed an increase in dose from stray radiation of about 50% compared to the 3D-conformal treatment. For the flattening filter-free photon beams, the dose from stray radiation far away from the target was slightly lower than the dose from a static treatment. The CyberKnife irradiation and the treatment using hard wedges increased the dose from stray radiation by nearly a factor of three compared to the 3D-conformal treatment. Conclusions: This study showed that the dose outside of the treated volume is influenced by several sources. Therefore, when comparing different treatment techniques, the dose ratios vary with distance to the isocenter. The effective dose outside the treated volume of intensity-modulated treatments with or without flattening filter was 10%-30% larger when compared to 3D-conformal radiotherapy. This dose increase is much lower than the monitor unit scaled effective dose from a static treatment.

Haelg, Roger A.; Besserer, Juergen; Schneider, Uwe [Institute for Radiotherapy, Radiotherapie Hirslanden AG, Aarau 5000 (Switzerland); Vetsuisse Faculty, University of Zurich, Zurich 8057 (Switzerland) and Institute for Radiotherapy, Radiotherapie Hirslanden AG, Aarau 5000 (Switzerland)

2012-12-15T23:59:59.000Z

150

United States Department of Energy Low Dose Radiation Research Program  

NLE Websites -- All DOE Office Websites (Extended Search)

History of the History of the United States Department of Energy (DOE) Low Dose Radiation Research Program: 1998-2008 Dr. Antone L. Brooks tbrooks@tricity.wsu.edu September 2012 Review Draft i Contents Preface............................................................................................................................................. v Summary ........................................................................................................................................ vi Acronyms and Initialisms ............................................................................................................. vii Chapter 1 Introduction ................................................................................................................... 1

151

Radiological Dose Assessment 8 2007 Site environmental report8-  

E-Print Network (OSTI)

to the absorbed radiation dose. The environmental TLDs used at the Lab- oratory are composed of calcium fluoride Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota, provides the guidelines

Homes, Christopher C.

152

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory,  

NLE Websites -- All DOE Office Websites (Extended Search)

Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Optimizing the Scientific, Regulatory, and Societal Impact of the DOE Low Dose Radiation Research Program Antone L. Brooks Why This Project? For maximum benefit, state-of-the-art research and new data from the Low Dose Radiation Research Program must be available to other scientists, regulatory agencies, and the public. This project stays abreast of scientific advances in the field, gathers, integrates, and summarizes the research within the program, and disseminates this information to appropriate scientific, regulatory, and public venues. Project Goals Provides a focal point for distribution of information generated in the program, to scientific committees, other governmental and regulatory agencies, and to the public Provides scientific support for the Low Dose Program website

153

Low dose diagnostic radiation exposure and cancer risk in Trp53...  

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University Abstract The cancer risk associated with exposure to low doses of ionizing radiation has traditionally been extrapolated from effects observed at high doses and high...

154

DOE Low Dose Radiation Research Workshop I November 1999  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation Research Program Low Dose Radiation Research Program U.S. Department of Energy Office of Biological and Environmental Research David G. Thomassen, Ph.D. Program Coordinator Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road Germantown, MD 20874-1290 Phone: 301-903-9817 Fax: 301-903-8521 Email: david.thomassen@science.doe.gov Arthur Katz, Ph.D. Life Sciences Division Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road Germantown, MD 20874-1290 Phone: 301-903-4932 Fax: 301-903-8521 Email: arthur.katz@science.doe.gov Marvin E. Frazier, Ph.D. Director, Life Sciences Division Office of Biological and Environmental Research U.S. Department of Energy, SC-72 19901 Germantown Road

155

Low dose ionizing radiation induces tumor growth promoting factors in  

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ionizing radiation induces tumor growth promoting factors in ionizing radiation induces tumor growth promoting factors in stress-induced premature senescent fibroblasts David Boothman University of Texas Southwestern Medical Center at Dallas Abstract Recent evidence suggest that the causes of cancer development are not limited to mutations within cancer cells, but also involve in alterations of cancer microenvironment. Senescent cells are irreversibly growth arrested, but remain metabolically active. Senescent cells, especially senescent fibroblasts in the stroma may provide a beneficial environment for tumor growth through secretion of certain factors. Accumulation of senescent cells in the stroma of patients repeatedly exposed to low doses of IR or low dose rates of IR, could be an important factor, causing alteration of the microenvironment that ultimately benefits tumor

156

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory  

NLE Websites -- All DOE Office Websites (Extended Search)

Optimizing the Scientific, Regulatory and Social Impact of the DOE Optimizing the Scientific, Regulatory and Social Impact of the DOE Low Dose Radiation Research Program. Authors: Antone L.Brooks, Richard J. Bull, Lezlie A. Couch. Institutions: Washington State University Tri-Cities The purpose of this project is to provide scientific, technical, and organizational support to optimize the impact of the DOE Low Dose Radiation Research Program. This project will serve as a focal point for collection and dissemination of scientific information from the scientists funded in the Program to the U.S. Department of Energy (DOE), the regulatory agencies, and the public. The project will be responsible for analysis of the scientific information in the broader context of biomedical research and will provide this information to the Office of Biological Research

157

Low Dose Radiation Research Program: Jian Jian Li  

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Jian Jian Li Jian Jian Li School of Health Sciences, Purdue University Newly Funded Projects Regulation of NF-kB and Mn SOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells, abstract, description. Technical Abstracts 2006 Workshops: NF-kB Mediated Signaling Network in Low Dose X-Ray Induced Adaptive Protection on Mouse and Human Skin Epithelial Cells Ahmed, K.M., Fan, M., Spitz, and Li, J.J. 2005 Workshops: Adaptive Response of Mouse Skin Epithelial Cells to Low Dose Ionizing Radiation: Induction of NF-κB, MnSOD, 14-3-3ζ and Cyclin B1. Li, J.J., Ahmed, K.M., Fan, M., Dong, S., Spitz, D.R., and Yu, C.-R. 2003 Workshops: Gene Expression Profiles of Human Skin Keratinocytes Exposed to Acute and Chronic Ionizing Radiation Li, J.J., Ozeki, M., Wang, T., Tamae, D., Nelson, D., Wyrobek, A., and

158

Low Dose Radiation Research Program: Radiation-Induced Nuclear Factor kB  

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Radiation-Induced Nuclear Factor kB mediates survival advantage by Radiation-Induced Nuclear Factor kB mediates survival advantage by Telomerase Activation. Authors: Natarajan M.,1 Mohan S.,2 Pandeswara, S.L.,1 and Herman T.S.1 Institutions: Departments of 1Radiation Oncology and 2Pathology, The University of Texas Health Science Center, San Antonio, Texas Activation of NF-kB in response to low doses of ionizing radiation was first shown in our laboratory. Although studies have shown that NF-kB plays an important role in anti-apoptotic function, little has been done to understand the molecular link between the activation of NF-kB and cellular outcome such as enhanced cell survival after low dose low-linear transfer (LET) radiation. Because upregulation of telomerase activity is associated with longevity and allows cells to escape from senescence, we hypothesize

159

Irradiators for measuring the biological effects of low dose-rate ionizing radiation fields  

E-Print Network (OSTI)

Biological response to ionizing radiation differs with radiation field. Particle type, energy spectrum, and dose-rate all affect biological response per unit dose. This thesis describes methods of spectral analysis, ...

Davidson, Matthew Allen

2011-01-01T23:59:59.000Z

160

Integrated beta and gamma radiation dose calculations for the ferrocyanide waste tanks  

SciTech Connect

This report contains the total integrated beta and gamma radiation doses in all the ferrocyanide waste tanks. It also contains estimated gamma radiation dose rates for all single-shell waste tanks containing a liquid observation well.

Parra, S.A.

1994-11-30T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Low Dose Radiation Research Program: Research Highlights - Ionizing  

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Affects Cancer Frequency and Characteristics by Acting Affects Cancer Frequency and Characteristics by Acting on the Microenvironment Background: For more than a quarter century the scientific rationale for extrapolating radiation health effects has been underpinned by biophysical target theory. Fundamental to target theory is that the effect (e.g., DNA damage, mutation, cancer) is proportional to dose based on interaction of energy with biological targets, specifically DNA. However, the biology following ionizing radiation is more than just DNA damage, repair, or misrepair. Cellular responses to ionizing radiation can affect phenotype, cell interactions, lineage commitment, differentiation and genomic stability, all of which have been widely documented in cultured cells and many observed in vivo. This class of non-targeted effects induced

162

Low Dose Radiation Research Program: Robert L. Ullrich  

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Robert L. Ullrich Robert L. Ullrich Colorado State University Currently Funded Projects Radiation Leukemogenesis at Low Dose Rates (NSCOR) Genetic Mechanisms of Induced Chromosomal Instability and their Relationships with Radiation Tumorigenesis Technical Abstracts 2006 Workshop: The Role of Telomere Dysfunction in Driving Genomic Instability Bailey, S.M., Williams, E.S., and Ullrich, R.L. 2005 Workshop: Dsyfunctional Mammalian Telomeres in DNA-PKcs Deficient Backgrounds Bailey, S.M., Williams, E., Hagelstrom, T., and Ullrich, R.L. 2003 Workshop: Dysfunctional Mammalian Telomeres Join to Double-Strand Breaks Bailey, S.M., Goodwin, E.H., Williams, E., and Ullrich, R.L. 2002 Workshop: Dysfunctional Telomeres, Radiation-Induced Instability and Tumorigenesis Bailey, S.M., Goodwin, E.H., Cornforth, M.N., and Ullrich, R.L.

163

Low Dose Radiation Research Program: Research Highlights - Collateral  

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Collateral Damage Collateral Damage Using targeted irradiation to understand radiation-induced effects in bystander cells chromosomal A typical example of chromosomal instability induction measured by chromosome-type aberrations in primary human lymphocytes at delay time post-irradiation of a fraction of the cell population. Similar types of aberrations were observed in whole irradiated population but were not observed in untreated cells. Munira Kadhim Background: It has long been understood that radiation exposure can influence cellular changes. Studies indicate that even very low doses of high linear energy transfer (LET) alpha-particle irradiation, such as that from environmental radon, can affect cells. Radiation-induced genomic instability can be observed in the progeny of irradiated cells and as a

164

Low Dose Radiation Research Program: Rainer K. Sachs  

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Rainer K. Sachs Rainer K. Sachs University of California, Berkeley Funded Projects BIO-BASED RISK MODELING 03-20: Modeling the Interrelations Among Radiation-Induced Bystander Effects, Genomic Instability and Cancer Cytogenetic Tests of Radiobiological Models Relating Epidemiologically Measurable Risks to Low-Dose Risks Technical Abstracts 2006 Workshop The Bystander Effect in Normal Human 3-D Tissue: Experiments, Models, and Implications Brenner, D., Ponnaiya, B., Shuryak, I., Sachs, R., and Geard, D. Radiation Carcinogenesis Risk as Influenced by Intercellular Interaction Hahnfeldt, P., Hlatky, L., and Sachs, R.K. 2005 Workshop: Modelling Intercellular Interactions During Radiation Carcinogenesis Sachs, R.K., Chan, M., Hlatky, L., and Hahnfeldt, P. 2003 Workshop: Chromosome Spatial Clustering Uncovered Through Radiogenic Aberrations

165

Relative Importance of Hip and Sacral Pain Among Long-Term Gynecological Cancer Survivors Treated With Pelvic Radiotherapy and Their Relationships to Mean Absorbed Doses  

Science Conference Proceedings (OSTI)

Purpose: To investigate the relative importance of patient-reported hip and sacral pain after pelvic radiotherapy (RT) for gynecological cancer and its relationship to the absorbed doses in these organs. Methods and Materials: We used data from a population-based study that included 650 long-term gynecological cancer survivors treated with pelvic RT in the Gothenburg and Stockholm areas in Sweden with a median follow-up of 6 years (range, 2-15) and 344 population controls. Symptoms were assessed through a study-specific postal questionnaire. We also analyzed the hip and sacral dose-volume histogram data for 358 of the survivors. Results: Of the survivors, one in three reported having or having had hip pain after completing RT. Daily pain when walking was four times as common among the survivors compared to controls. Symptoms increased in frequency with a mean absorbed dose >37.5 Gy. Also, two in five survivors reported pain in the sacrum. Sacral pain also affected their walking ability and tended to increase with a mean absorbed dose >42.5 Gy. Conclusions: Long-term survivors of gynecological cancer treated with pelvic RT experience hip and sacral pain when walking. The mean absorbed dose was significantly related to hip pain and was borderline significantly related to sacral pain. Keeping the total mean absorbed hip dose below 37.5 Gy during treatment might lower the occurrence of long-lasting pain. In relation to the controls, the survivors had a lower occurrence of pain and pain-related symptoms from the hips and sacrum compared with what has previously been reported for the pubic bone.

Waldenstroem, Ann-Charlotte, E-mail: ann-charlotte.waldenstrom@oncology.gu.se [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Department of Oncology, Sahlgrenska University Hospital, Gothenburg (Sweden); Olsson, Caroline [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Department of Radiation Physics, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Wilderaeng, Ulrica [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden)] [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Dunberger, Gail; Lind, Helena; Alevronta, Eleftheria [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)] [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Al-Abany, Massoud [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden); Department of Hospital Physics, Karolinska University Hospital, Stockholm (Sweden); Tucker, Susan [Department of Bioinformatics and Computational Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States)] [Department of Bioinformatics and Computational Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX (United States); Avall-Lundqvist, Elisabeth [Department of Gynecologic Oncology, Karolinska University Hospital, Stockholm (Sweden)] [Department of Gynecologic Oncology, Karolinska University Hospital, Stockholm (Sweden); Johansson, Karl-Axel [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg (Sweden)] [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg (Sweden); Steineck, Gunnar [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden) [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg (Sweden); Division of Clinical Cancer Epidemiology, Department of Oncology-Pathology, Karolinska Institute, Stockholm (Sweden)

2012-10-01T23:59:59.000Z

166

Low Dose Radiation Research Program: Low Dose Response of Respiratory Cells  

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Response of Respiratory Cells in Intact Tissues and Reconstituted Response of Respiratory Cells in Intact Tissues and Reconstituted Tissue John Ford Department of Nuclear Engineering Texas A & M University Why this Project? Using the well-established rat trachea model to test the hypothesis that normal respiratory epithelial cells transmit signals to neighboring cells in response to very low dose radiation exposure. Project Goals By comparing the responses shown by cells in these normal rodent respiratory tissues to those seen for human respiratory epithelial cells in reconstituted tissue constructs, it will be possible to better understand the responds in human respiratory cells in vivo. These studies will characterize responses after exposure to a variety of radiation types and dose distributions. Experimental Approach

167

Electron Photon Absorbed Dose  

Science Conference Proceedings (OSTI)

... is in progress, with preliminary results obtained for both high-energy electrons (at the ... of Clinac 12 MeV, 16 MeV and 20 MeV electron beams at ...

2013-03-13T23:59:59.000Z

168

Equations for Estimating the Similarity Parameter from Radiation Measurements within Weakly Absorbing Optically Thick Clouds  

Science Conference Proceedings (OSTI)

Series expansions are derived for estimating the similarity parameter, which is a combination of the single-scattering albedo and asymmetry factor, from radiance measurement deep in the interior of a weary absorbing cloud. One expansion requires ...

T. Duracz; N. J. McCormick

1986-03-01T23:59:59.000Z

169

NIST Ionizing Radiation Division 2001 - Program Directions  

Science Conference Proceedings (OSTI)

... seen a tremendous increase in the use of low-energy photon ... for the high levels of absorbed dose used in the industrial radiation processing of ...

170

The proceedings of a symposium on dose rate in mammalian radiation biology, April 29 - May 1, 1968  

SciTech Connect

MAMMALIA. Radiation effects on, effects of dose rate on; RADIOBIOLOGY. Conference on effects of dose rate on radiosensitivity of mammals.

Brown, D.G.; Cragle, R.G.; Noonan, T.R. (eds.)

1968-01-01T23:59:59.000Z

171

Low-Dose Radiation Cataract and Genetic Determinants of Radiosensitivity  

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Cataract and Genetic Determinants of Radiosensitivity Cataract and Genetic Determinants of Radiosensitivity Kleiman, N.J. 1 , Smilenov, L.B. 2 , Brenner, D.J. 2 and Hall, E.J. 2 1 Department of Environmental Health Sciences, Mailman School of Public Health & 2 The Center for Radiological Research, College of Physicians & Surgeons, Columbia University, New York 10032 The lens of the eye is one of the most radiosensitive tissues in the body. Ocular ionizing radiation exposure results in characteristic, dose related, progressive lens changes leading to cataract formation. While initial, early stages of such opacification may not cause visual disability, the severity of such changes progressively increases with dose until vision is impaired and cataract extraction surgery may be required. The

172

Low Dose Radiation Research Program: Assessing Biological Function of DNA  

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Assessing Biological Function of DNA Damage Response Genes Assessing Biological Function of DNA Damage Response Genes Larry H. Thompson Lawrence Livermore National Laboratory Why This Project To understand the relative importance of individual DNA repair and DNA-damage response pathways to the recovery of mammalian cells after exposure to low doses of ionizing radiation (IR). This understanding may lead to better ways of setting limits on human exposure to IR. In spite of the discovery of many mammalian DNA repair genes, our current knowledge of how many of these genes contribute to cellular recovery from IR exposure is quite limited. Project Goals Measure cellular responses at doses in the 5-100 cGy range, which generally cause changes too small to detect in normal, repair-proficient cells Focus on DNA double-strand breaks (DSBs) and DNA oxidative base

173

Low Dose Radiation Research Program: Quantification of Repair of  

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Quantification of Repair of Low-Dose-Induced DNA Double-Strand Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells Authors: David Schild,1 and Larry H. Thompson,2 Institutions: 1Life Sciences Division, Lawrence Berkeley National Laboratory; and 2BBR Program, Lawrence Livermore National Laboratory Double-strand breaks (DSBs) are the biochemical lesions of primary concern in radiation related health effects. Compelling evidence from rodent and chicken model systems indicates that homologous recombinational repair (HRR) plays an essential role for cell viability in the repair of spontaneous DSBs arising during DNA replication and an important role in the repair of IR-induced DSBs. IR-induced DSBs are also repaired by error-prone nonhomologous end joining (NHEJ). Using hTERT-immortalized

174

Low Dose Radiation Research Program: Optimizing the Scientific, Regulatory  

NLE Websites -- All DOE Office Websites (Extended Search)

Optimizing the Scientific, Regulatory and Societal Impact of the DOE Optimizing the Scientific, Regulatory and Societal Impact of the DOE Low Dose Research Program Authors: Antone L. Brooks Institution: Washington State University Tri-Cities Richland, Washington The purpose of this project is to provide a focal point for communication of the research results from the DOE Low Dose Radiation Research Program. The major communication tool provided by this project is a Website at Washington State University. The website is being maintained to provide communication between the scientific advances generated by the research program and scientists both in and outside the program, policy makers, regulators and the public. The website also contains a number of presentations and illustrations that are written so that they will be easy

175

Low Dose Ionizing Radiation Modulates Immune Function New Project Overview  

NLE Websites -- All DOE Office Websites (Extended Search)

Modulates Immune Function New Project Overview Modulates Immune Function New Project Overview Gregory Nelson Loma Linda University Abstract The immune system provides the first line of defense for exposures to environmental hazards. Protective immunity mechanisms using innate or adaptive responses are employed to mitigate acute challenges or amplify the readiness of the system to respond to future challenges. Some stimuli lead to amplified inflammatory reactions such as delayed hypersensitivity which is required for immunity to parasites and can also lead to adverse consequences such as contact dermatitis. Radiation exposure has the potential to aggravate hypersensitivity reactions as well as to suppress protective immunity. Ionizing radiation at high doses has long been recognized as highly effective in destroying cells of the immune system,

176

Low Dose Radiation Research Program: Computational Modeling of Biochemical  

NLE Websites -- All DOE Office Websites (Extended Search)

Computational Modeling of Biochemical Pathways Linking Ionizing Computational Modeling of Biochemical Pathways Linking Ionizing Radiation to Cell Cycle Arrest, Apoptosis, and Tumor Incidence Authors: Yuchao Maggie Zhao and Rory Conolly Institutions: Center for Computational Systems Biology CIIT Centers for Health Research Long-Range Goal: To develop an integrated, computational framework for the prediction of low-dose-response to ionizing radiation (IR) in people. Methodology: To provide a flexible framework to evaluate mechanisms of cellular adaptive responses after exposure to IR, three progressively more complicated descriptions of biochemical pathways linking DNA damage with cell-cycle checkpoint control and apoptosis were developed. These descriptions focus on p53-dependent checkpoint arrest and apoptosis, p73-dependent apoptosis, and Chk2-dependent checkpoint arrest,

177

Low Dose Radiation Research Program: Characterizing Bystander Effects  

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Irradiation. Irradiation. Authors: L.A. Braby and J.R. Ford. Institutions: Texas A&M University. Bystander effects, which are typically seen as in increase in the cellular concentration of specific repair related molecules or as cytogenetic changes which appear to be the consequence of DNA damage, may be a significant factor in the risk of long-term health effects of low doses of radiation. These effects clearly increase the effective size of the target for radiation response, from the diameter of a single cell or cell nucleus to something significantly larger, by bringing additional cells into the process. It is unclear whether this larger target will result in an increase or a decrease in the probability of inducing a change which would be detrimental to the health of the organism, but it clearly reduces the

178

Low Dose Radiation Research Program: Genetic Mechanisms of Induced  

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Mechanisms of Induced Chromosomal Instability and their Mechanisms of Induced Chromosomal Instability and their Relationships with Radiation Tumorigenesis Robert Ullrich Colorado State University Why This Project A combination of epidemiological, experimental, animal, and cellular molecular data is used in the estimation of tumor risk after low doses of low-LET radiation. Uncertainties are recognized in the interpretation of all these data sets, and recent findings concerning genomic instability in irradiated cells challenge the conventional view that induced DNA damage is expressed during the immediate post-irradiation cell cycle. These data on genomic instability are based largely upon studies of cell cultures the mechanisms involved and implications for tumor formation in living organisms remain unclear. Nevertheless, if induced genomic instability were

179

Low Dose Radiation Research Program: Cooperation Between Homologous  

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Cooperation Between Homologous Recombination and the Fanconi Anemia Cooperation Between Homologous Recombination and the Fanconi Anemia Cancer Suppressor Proteins in Minimizing Spontaneous and Radiation-Induced Chromosomal Instability Authors: Larry H. Thompson, John M. Hinz, Robert S. Tebbs, and N. Alice Yamada Institutions: Biosciences Directorate, Lawrence Livermore National Laboratory, Livermore, California Purpose and experimental approach. This study addresses the genetic basis of spontaneous mutagenesis as a means of understanding the DNA damage-response pathways that maintain chromosome stability. It is our view that knowledge of these processes is fundamental to understanding how low dose ionizing radiation (IR) produces chromosomal rearrangements that lead to carcinogenesis. Endogenous oxidative DNA damage is presumed to be a

180

Radiation dose-rate meter using an energy-sensitive counter  

DOE Patents (OSTI)

A radiation dose-rate meter is provided which uses an energy-sensitive detector and combines charge quantization and pulse-rate measurement to monitor radiation dose rates. The charge from each detected photon is quantized by level-sensitive comparators so that the resulting total output pulse rate is proportional to the dose-rate. 3 figs.

Kopp, M.K.

1986-12-17T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Radiation dose-rate meter using an energy-sensitive counter  

DOE Patents (OSTI)

A radiation dose-rate meter is provided which uses an energy-sensitive detector and combines charge quantization and pulse-rate measurement to monitor radiation dose rates. The charge from each detected photon is quantized by level-sensitive comparators so that the resulting total output pulse rate is proportional to the dose-rate.

Kopp, Manfred K. (Oak Ridge, TN)

1988-01-01T23:59:59.000Z

182

The risk of leukemia from low doses of low-LET radiation  

Science Conference Proceedings (OSTI)

In this communication, we examine the evidence (if any) for a nonlinear dose response in relation to leukemia mortality in the Japanese A-bomb population. Specifically, we seek an estimate of the probability that, at low doses of radiation, the relative ... Keywords: A-bomb survivors, Hormesis, Leukemia risk, Low doses of radiation

M. Zaider

2001-06-01T23:59:59.000Z

183

Low Dose Radiation Research Program: Use of Computational Modeling to  

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Use of Computational Modeling to Evaluate Hypotheses about the Use of Computational Modeling to Evaluate Hypotheses about the Molecular and Cellular Mechanisms of Bystander Effects Authors: Yuchao “Maggie” Zhao and Rory Conolly Institutions: CIIT Centers for Health Research, 6 Davis Drive, Research Triangle Park, North Carolina A detailed understanding of the biological mechanisms of radiation-induced damage at the molecular and cellular levels is needed for accurate assessment of the shape of the dose-response curve for radiationinduced health effects in the intact organism. Computational models can contribute to the improved understanding of mechanisms through integration of data and quantitative evaluation of hypotheses. We propose to develop a novel computational model of bystander effects elicited by oxidative stress and a

184

Investigation of non-targeted effects of low dose ionizing radiation...  

NLE Websites -- All DOE Office Websites (Extended Search)

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains...

185

Effect of Low Dose Radiation on Antioxidant Levels in Rat Brain  

NLE Websites -- All DOE Office Websites (Extended Search)

Low Dose Radiation on Antioxidant Levels in Rat Brain Mohan Doss Fox Chase Cancer Center Abstract Background: Parkinsons disease (PD) is characterized by progressive...

186

Using Co-Regulation to Understand Low-Dose Ionizing Radiation...  

NLE Websites -- All DOE Office Websites (Extended Search)

with low and high doses of ionizing radiation (IR). Pathway analysis suggested that chromatin structure, as well as transcription control, plays a large role in linking gene...

187

Profiling of MnSOD Interaction Proteins in Low-Dose Radiation...  

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Proteins in Low-Dose Radiation Induced Adaptive Response Angela Eldridge 1 , Ming Fan 1 , Demet Candas 1 , Brett Chromy, and Jian Jian Li 1 1 Department of Radiation...

188

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 3  

Science Conference Proceedings (OSTI)

... of high levels of absorbed dose, as required in the industrial radiation processing of ... tremendous increase in the use of low-energy, photon ...

189

NIST Ionizing Radiat. Div. - 2002: Strategic Focus 3  

Science Conference Proceedings (OSTI)

... of high levels of absorbed dose, as required in the industrial radiation processing of ... tremendous increase in the use of low-energy, photon ...

190

Low Dose Radiation Research Program: David J. Chen  

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2003 Workshop: Gene Expression Profile of Normal Human Fibroblast After Ionizing Irradiation, a comparison study between low dose and high dose. Chen, D.J. 2002 Workshop:...

191

Low Dose Radiation Research Program Website ? Highlighting Low...  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Program Website - Highlighting Low Dose Research Bill Morgan, Principal Investigator; Julie Wiley, Website Content Manager; Christine Novak, Webmaster The Low Dose...

192

Environmental radiation dose criteria and assessment: pathway modeling and surveillance  

SciTech Connect

From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). The controversy in recent years over the extent of the risk to the public from environmental radioactivity attributable to nuclear facilities (in particular nuclear power plants and fuel reprocessing facilities) has resulted in a lowering of previously acceptable environmental radiation levels. The proposal by the AEC to limit effluents from light-water-cooled nuclear reactors so that the exposure of any individual in the public would not exceed 5 mR/yr, and the pronouncement by the BEIR Committee that the current environmental radiation protection guides are unnecessarily high, are illustrative. In turn the AEC has issued a Safety Guide calling for considerable refinement in the measuring and reporting of effluents from nuclear power plants, and has only recently issued a counterpart dealing with the measuring and reporting of radioactivity in the environs of nuclear power plants. The EPA has also recently issued a guide for the surveillance of environmental radioactivity. Currently, power reactor operators are being required by the AEC Regulatory Staff to conduct detailed, sensitive environmental surveillance. Much of this appears to be based on extremely conservative assumptions throughout, including doseeffect relationships, exposure situations, pathway models, reconcentration factors and intakes, which cannot be substantiated when examined in the light of current experience in the vicinity of existing power reactors. The expenditures occasioned by the required additional in-plant features necessary to meet the currently proposed effluent release criteria appear difficult to justify on a reasonable basis. Environmental monitoring at the proposed concentration limits appear even more excessive in terms of dollars per man-rem of potential dose commitment. (auth)

Hull, A.P.

1973-01-01T23:59:59.000Z

193

Low Dose Radiation Research Program: Induction of Genomic Instability...  

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Brook Why This Project Genomic instability is an important step in radiation-induced cancer. We will investigate one potential repair mechanism involved in radiation-induced...

194

Low Dose Radiation Research Program: Research Highlights - 2010  

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DNA Double-Strand Break Repair Capacities Before and After Exposure to Low DNA Double-Strand Break Repair Capacities Before and After Exposure to Low Dose Radiation Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM, DNA damage-responsive kinase; red). (C) Merge of images A and B. (White arrows mark large γ-H2AX foci and coincident γ-H2AX/pATM foci that were positively scored; yellow arrows mark small γ-H2AX foci that lack corresponding pATM foci that were not scored.) Enlarge Image Immunochemical detection of DSB foci in the nuclei of human fibroblasts. (A) γ-H2AX phospho-serine 139 foci (chromatin marker of DSBs; green). (B) ataxia-telangiectasia mutated phospho-serine 1981 foci (ATM,

195

Complexity analysis of the UV radiation dose time series  

E-Print Network (OSTI)

We have used the Lempel-Ziv and sample entropy measures to assess the complexity in the UV radiation activity in the Vojvodina region (Serbia) for the period 1990-2007. In particular, we have examined the reconstructed daily sum (dose) of the UV-B time series from seven representative places in this region and calculated the Lempel-Ziv Complexity (LZC) and Sample Entropy (SE) values for each time series. The results indicate that the LZC values in some places are close to each other while in others they differ. We have devided the period 1990-2007 into two subintervals: (a) 1990-1998 and (b) 1999-2007 and calculated LZC and SE values for the various time series in these subintervals. It is found that during the period 1999-2007, there is a decrease in their complexities, and corresponding changes in the SE, in comparison to the period 1990-1998. This complexity loss may be attributed to increased (i) human intervention in the post civil war period (land and crop use and urbanization) and military activities i...

Mihailovic, Dragutin T

2013-01-01T23:59:59.000Z

196

Estimation of Internal Radiation Dose from both Immediate Releases and Continued Exposures to Contaminated Materials  

Science Conference Proceedings (OSTI)

A brief description is provided of the basic concepts related to 'internal dose' and how it differs from doses that result from radioactive materials and direct radiation outside of the body. The principles of radiation dose reconstruction, as applied to both internal and external doses, is discussed based upon a recent publication prepared by the US National Council on Radiation Protection and Measurements. Finally, ideas are introduced related to residual radioactive contamination in the environment that has resulted from the releases from the damaged reactors and also to the management of wastes that may be generated in both regional cleanup and NPP decommissioning.

Napier, Bruce A.

2012-03-26T23:59:59.000Z

197

Low Dose Radiation Research Program: Comparison of DNA Damage Risk from  

NLE Websites -- All DOE Office Websites (Extended Search)

Comparison of DNA Damage Risk from Low-Dose Radiation and Folate Comparison of DNA Damage Risk from Low-Dose Radiation and Folate Deficiency. Authors: Chantal Courtemanche, Arnold C. Huang, Nicole Kerry, Bernice Ng, and Bruce N. Ames. Institutions: Children’s Hospital Oakland Research Institute, Oakland, California. Our overall goal is to understand and quantify the real effects of low-dose radiation by measuring direct and specific cellular changes. However, since the background dose of radiation to which most individuals are exposed is well below the levels where significant biological effects, such as mutation or tumor induction, are observed, our novel approach is to compare the consequences of radiation to those of specific nutritional deficiencies. By determining which of these two common stresses at physiologically relevant doses leads to a greater amount of DNA damage, we

198

Low dose diagnostic radiation exposure and cancer risk in Trp53+/- mice  

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diagnostic radiation exposure and cancer risk in Trp53+/- mice diagnostic radiation exposure and cancer risk in Trp53+/- mice K Taylor, N Phan, ME Cybulski, L Laframboise, DR Boreham Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main Street West, Hamilton ON L8S 4K1 The cancer risk associated with exposure to low doses of ionizing radiation has traditionally been extrapolated from effects observed at high doses and high dose rates using a linear no threshold model. Based on this approach, it has been postulated that human exposure to medical imaging involving low doses of x-rays and gamma rays increase an individual's risk of developing cancer throughout their lifetime. Conversely, there is evidence that low doses of gamma radiation increase the latency period of cancer depending upon genotype, cancer type, and the magnitude of

199

Apoptosis as a Mechanism for Low Dose Radiation-and Amifostine-Mediated  

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Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Apoptosis as a Mechanism for Low Dose Radiation- and Amifostine-Mediated Chromosomal Inversion Responses Pam Sykes Flinders University and Medical Centre Abstract Low dose radiation and the chemical radioprotector amifostine have both been shown to protect cells from the immediate and delayed effects of radiation exposure. They display a number of distinct similarities including their ability to protect cells against radiation-induced DNA damage, radiation-induced cell death and metastases formation. Amifostine, which protects cells from the toxic effects of ionizing radiation, has a broad range of activities including free radical scavenging, polyamine-like DNA binding, and induction of hypoxia and redox-regulated genes. Amifostine’s ability to protect cells is often

200

Dose distribution for /sup 125/I implants due to anisotropic radiation emission and unknown seed orientation  

SciTech Connect

Variations in dose distribution due to anisotropic radiation emission around /sup 125/I seeds and a lack of knowledge about the orientation of the implanted seeds have been investigated. Upper and lower bounds for dose distributions have been calculated for planar implants using the experimentally determined angular dose distribution around a typical /sup 125/I seed. Results of our study suggest that significant dose variations in the center and the periphery of the implanted area are possible.

Prasad, S.C.; Bassano, D.A.; Fear, P.I.

1987-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Low Dose Radiation Research Program: Communicating the Science of the Low  

NLE Websites -- All DOE Office Websites (Extended Search)

Communicating the Science of the Low Dose Radiation Research Program Communicating the Science of the Low Dose Radiation Research Program Authors: John S. Wassom, Elizabeth T. Owens, Sheryl A. Martin, Amy K. Wolfe, Margaret K. Lyday,* and Susan L. Dimmick** Institutions: Oak Ridge National Laboratory, *Keener Communications, and the **University of Tennessee Graduate School of Medicine. Summary The project team developed a communications plan based on an explicit communications strategy. The plan presents a set of strategic goals, identifies categories of stakeholders relevant to the program, and suggests methods that can be used to achieve strategic goals and reach targeted stakeholders. Context is key to the communication plan. Providing contextual information about low dose radiation, radiation biology, and Low Dose Radiation

202

Annual report shows potential INL radiation dose well below safe regulatory  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Annual report shows potential INL radiation dose well below safe Annual report shows potential INL radiation dose well below safe regulatory limits Annual report shows potential INL radiation dose well below safe regulatory limits August 9, 2011 - 12:00pm Addthis Media Contact Tim Jackson, DOE-Idaho Operations Office 208-526-8484 The U.S. Department of Energy's Idaho Operations Office reported this month that radiation from the site falls well below limits established by the U.S. Environmental Protection Agency. The annual report's conclusions are supported by direct environmental monitoring data routinely taken during the year, and show that activities at the Idaho National Laboratory (INL) site are protective of human health and the environment. Data shows that the INL site potential radiation dose is less than 1% of

203

Radiation Leukemogenesis: Applying Basic Science of Epidemiological Estimates of Low Dose Risks and Dose-Rate Effects  

SciTech Connect

The next stage of work has been to examine more closely the A-bomb leukemia data which provides the underpinnings of the risk estimation of CML in the above mentioned manuscript. The paper by Hoel and Li (Health Physics 75:241-50) shows how the linear-quadratic model has basic non-linearities at the low dose region for the leukemias including CML. Pierce et. al., (Radiation Research 123:275-84) have developed distributions for the uncertainty in the estimated exposures of the A-bomb cohort. Kellerer, et. al., (Radiation and Environmental Biophysics 36:73-83) has further considered possible errors in the estimated neutron values and with changing RBE values with dose and has hypothesized that the tumor response due to gamma may not be linear. We have incorporated his neutron model and have constricted new A-bomb doses based on his model adjustments. The Hoel and Li dose response analysis has also been applied using the Kellerer neutron dose adjustments for the leukemias. Finally, both Pierce's dose uncertainties and Kellerer neutron adjustments are combined as well as the varying RBE with dose as suggested by Rossi and Zaider and used for leukemia dose-response analysis. First the results of Hoel and Li showing a significantly improved fit of the linear-quadratic dose response by the inclusion of a threshold (i.e. low-dose nonlinearity) persisted. This work has been complete for both solid tumor as well as leukemia for both mortality as well as incidence data. The results are given in the manuscript described below which has been submitted to Health Physics.

Hoel, D. G.

1998-11-01T23:59:59.000Z

204

Estimation of radiation-induced cancer from three-dimensional dose distributions: Concept of organ equivalent dose  

SciTech Connect

Purpose: Estimates of secondary cancer risk after radiotherapy are becoming more important for comparative treatment planning. Modern treatment planning systems provide accurate three-dimensional dose distributions for each individual patient. These data open up new possibilities for more precise estimates of secondary cancer incidence rates in the irradiated organs. We report a new method to estimate organ-specific radiation-induced cancer incidence rates. The concept of an organ equivalent dose (OED) for radiation-induced cancer assumes that any two dose distributions in an organ are equivalent if they cause the same radiation-induced cancer incidence. Methods and Materials: The two operational parameters of the OED concept are the organ-specific cancer incidence rate at low doses, which is taken from the data of the atomic bomb survivors, and cell sterilization at higher doses. The effect of cell sterilization in various organs was estimated by analyzing the secondary cancer incidence data of patients with Hodgkin's disease who were treated with radiotherapy in between 1962 and 1993. The radiotherapy plans used at the time the patients had been treated were reconstructed on a fully segmented whole body CT scan. The dose distributions were calculated in individual organs for which cancer incidence data were available. The model parameter that described cell sterilization was obtained by analyzing the dose and cancer incidence rates for the individual organs. Results: We found organ-specific cell radiosensitivities that varied from 0.017 for the mouth and pharynx up to 1.592 for the bladder. Using the two model parameters (organ-specific cancer incidence rate and the parameter characterizing cell sterilization), the OED concept can be applied to any three-dimensional dose distribution to analyze cancer incidence. Conclusion: We believe that the concept of OED presented in this investigation represents a first step in assessing the potential risk of secondary cancer induction after the clinical application of radiotherapy.

Schneider, Uwe [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland)]. E-mail: uwe.schneider@psi.ch; Zwahlen, Daniel [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Ross, Dieter [Division of Medical Physics, Department of Radiation Oncology and Nuclear Medicine, City Hospital Triemli, Zurich (Switzerland); Kaser-Hotz, Barbara [Division of Diagnostic Imaging and Radio-Oncology, Vetsuisse Faculty, University of Zuerich, Zurich (Switzerland)

2005-04-01T23:59:59.000Z

205

Low Dose Radiation Research Program: X-ray Microbeam Bystander...  

NLE Websites -- All DOE Office Websites (Extended Search)

experiments, cultures grown in microwell slide chambers were irradiated with precise stripes of dose up to 100m wide. Samples were processed for the expression of...

206

Low Dose Radiation Research Program: Past Funded Projects-Archive  

NLE Websites -- All DOE Office Websites (Extended Search)

Berkeley, CA A Quantitative Assessment of Bystander Mutagenesis in the Mouse Mammary Gland In Vivo Bruce E. Lehnert Los Alamos National Laboratory, Los Alamos, NM Low Dose...

207

Low Dose Radiation Research Program: Quantification of Repair...  

NLE Websites -- All DOE Office Websites (Extended Search)

Quantification of Repair of Low-Dose-Induced DNA Double-Strand Breaks in Diploid Human Cells David Schild Lawrence Berkeley National Laboratory Berkeley, California Why this...

208

Low Dose Radiation | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Radiobiology: Low Dose Radiation Radiobiology: Low Dose Radiation Research Biological and Environmental Research (BER) BER Home About Research Research Abstracts Searchable Archive of BER Highlights External link Biological Systems Science Division (BSSD) Genomic Science DOE Bioenergy Research Centers Radiochemistry & Imaging Instrumentation Radiobiology: Low Dose Radiation Research DOE Human Subjects Protection Program Structural Biology DOE Joint Genome Institute Climate and Environmental Sciences Division (CESD) Facilities Science Highlights Benefits of BER Funding Opportunities Biological & Environmental Research Advisory Committee (BERAC) News & Resources Contact Information Biological and Environmental Research U.S. Department of Energy SC-23/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3251 F: (301)

209

Measurements of cosmic radiation dose in subsonic commercial aircraft compared to the city-pair dose calculation  

SciTech Connect

The radiation dose received by passengers during flight on conventional jet aircraft was determined as a function of exposure to cosmic radiation, solar radiation, flight time, and flight path. The dosimetric measurements were made with thermoluminescent dosimeters (TLD's) and with emulsions of three types sealed in plastic packets. These packets were sent by air mail back and forth from Berkeley, California to five cities and a dose sufficiently above background for a satisfactory measurement was accumulated by the TLD's on one round trip and by the emulsions on three round trips. It was concluded that both experiments and theory show that the total doses received at present day conventional jet aircraft altitudes are considerably higher than those encountered in supersonic flights at much higher altitudes, even though the dose rate is lower at these lower altitudes, when the longer time of exposure at the lower altitudes is taken into consideration. Computer programs used in the dose calculations are included. (CH)

Wallace, R.

1973-07-16T23:59:59.000Z

210

ALLDOS: a computer program for calculation of radiation doses from airborne and waterborne releases  

Science Conference Proceedings (OSTI)

The computer code ALLDOS is described and instructions for its use are presented. ALLDOS generates tables of radiation doses to the maximum individual and the population in the region of the release site. Acute or chronic release of radionuclides may be considered to airborne and waterborne pathways. The code relies heavily on data files of dose conversion factors and environmental transport factors for generating the radiation doses. A source inventory data library may also be used to generate the release terms for each pathway. Codes available for preparation of the dose conversion factors are described and a complete sample problem is provided describing preparation of data files and execution of ALLDOS.

Strenge, D.L.; Napier, B.A.; Peloquin, R.A.; Zimmerman, M.G.

1980-10-01T23:59:59.000Z

211

Low Dose Radiation Research Program: Gene Expression Profile...  

NLE Websites -- All DOE Office Websites (Extended Search)

human cDNA clones, we focused on differential gene expression for a low-dose x-ray irradiation at 2cGy and its comparison with high-dose at 4Gy. Four time points were studied at...

212

Low Dose Radiation Research Program: Identification of Mouse Genetic  

NLE Websites -- All DOE Office Websites (Extended Search)

Mouse Genetic Susceptibility to Radiation Carcinogenesis Mouse Genetic Susceptibility to Radiation Carcinogenesis Allan Balmain University of California, San Francisco San Francisco, CA. (Jointly funded by NASA and DOE) Why this Project? To identify pathways that control genetic susceptibility to radiation-induced DNA damage and tumor development using novel developments in genomics together with mouse genetics. Project Goals To identify genetic loci that trigger rapid tumor development of mice after radiation. To characterize new genes at these loci that act as tumor suppressor genes or oncogenes. Experimental Approach New candidate-radiation susceptibility genes will be identified using a unique haplotyping approach. Using DNA from radiation-induced lymphoma, changes in the gene copy number can be detected using BAC microarrays. The

213

Low Dose Radiation Research Program: James E. Morris  

NLE Websites -- All DOE Office Websites (Extended Search)

Northwest National Laboratories Past Funded Project Sensitivity to radiation-induced cancer in hemachromatosis. Publications Stevens, R.G., Morris, J.E., and Anderson, L.E....

214

Low Dose Radiation Research Program: Walter E. Wilson  

NLE Websites -- All DOE Office Websites (Extended Search)

Monte Carlo simulation of the spatial distribution of energy deposition for an electron microbeam. Radiation Research: 163(4):468472. Mainardi, E., Donahue, R.J.,...

215

Mechanism underlying mTOR-associated Protection in Low Dose Radiation...  

NLE Websites -- All DOE Office Websites (Extended Search)

low-dose radiation-induced adaptive resistance. Oncogene 27: 6738-6748. 2. Gwinn DM, Shackelford DB, Egan DF, Mihaylova MM, Mery A, Vasquez DS, Turk BE, and Shaw RJ. (2008). AMPK...

216

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES  

NLE Websites -- All DOE Office Websites (Extended Search)

LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES LOW DOSE PHOTON RADIATION-INDUCED CHANGES IN T HELPER LYMPHOCYTES Daila S. Gridley 1,2 , Asma Rizvi 2 , Xian Luo 1 , Adeola Y. Makinde 2 , Steve Rightnar 1 , Jian Tian 1 , Melba L. Andres 1 , James M. Slater 1 , and Michael J. Pecaut 1,2 Departments of 1 Radiation Medicine and 2 Biochemistry & Microbiology Loma Linda University and Medical Center, Loma Linda, CA 92354 USA Health risks due to protracted low dose irradiation remain unclear. This project investigates T helper (Th) lymphocyte function and the cellular milieu in which they reside under conditions of low dose, low- linear energy transfer (LET) radiation exposure. The Th cells are important because they secrete cytokines essential for generating optimal immune defenses against tumor, virus-infected, and other

217

Low-Dose Ionizing Radiation Alters the Epigenome of the Avy Mouse  

NLE Websites -- All DOE Office Websites (Extended Search)

Medical Center Abstract Background: Humans have evolved and thrived amidst constant low-dose (0-10 cGy) background radiation exposure from natural sources. Currently, however, the...

218

Low dose ionizing radiation (IR) signaling regulation in vivo...  

NLE Websites -- All DOE Office Websites (Extended Search)

studies from our lab indicated that human cells exposed to low doses of IR caused growth stimulation, speeding cells up in their cell cycle division (i.e., checkpoint regulation),...

219

Low Dose Radiation Research Program: Multi-cellular Crosstalk...  

NLE Websites -- All DOE Office Websites (Extended Search)

grown in microwell slide chambers will be irradiated with precise 100-mm-wide exposure stripes of dose to define the responses in exposed and bystander cells The time course of the...

220

Low Dose Radiation Research Program: Induction of Genomic Instability...  

NLE Websites -- All DOE Office Websites (Extended Search)

genetic backgrounds (BALBcJ and C57BL6J mice) collected at different times post-irradiation (i.e. 1 hr, 4 hrs, 1 month and 6 months). A total of five mice per dose per strain...

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Low Dose Radiation Research Program: Biological Response of Individual...  

NLE Websites -- All DOE Office Websites (Extended Search)

Response of Individual Cells Following Electron Microbeam Irradiation L. A. Braby and J. R. Ford Texas A&M University, College Station Texas In recent years studies with low doses...

222

Low Dose Radiation Research Program: Techniques and Technology  

NLE Websites -- All DOE Office Websites (Extended Search)

Role of the Number and Spacing of Electron Tracks on the Consequences of Low Dose Irradiation X-ray microfocus source The new X-ray microfocus source Enlarge Image. Melvyn...

223

THE ROLES OF SUPEROXIDE DISMUTAGE (SOD) IN LOW DOSE RADIATION...  

NLE Websites -- All DOE Office Websites (Extended Search)

the detoxifying enzymes may be even more prominent in the case of low-dose, low-LET irradiation, as the majority of genetic damage may be caused by secondary oxidative species. In...

224

Low Dose Radiation Research Program: Impact of Genetic Factors...  

NLE Websites -- All DOE Office Websites (Extended Search)

following paternal F0 137Cs gamma irradiation with doses of 1.0 Gy in CD1 mice. Pilot studies demonstrate effects in at least the F1 generation following paternal F0...

225

A standard dose of radiation for microscopic disease is not appropriate  

SciTech Connect

Elective irradiation of sites of potential occult tumor spread is often part of a patient's radiation therapy program. The required radiation dose (D) depends on the probability that occult disease exists (P(occ)), the number of sites at risk (A), the number of tumor clonogens present (Ni), their radiation sensitivity, and the desired control rate. An exponential model of cell survival is used to quantify the importance of these factors. Control Probability = (1 - Pocc x (1 - e-Ni x (SF2)D/2))A; SF2 = surviving fraction after 2 Gy. Implications for clinical radiation therapy include: 1. Since the number of clonogens in an occult site may vary from 10 degrees to 10(8), Ni is the major determinant of the required dose. The intrinsic radiation sensitivity of the clonogens (SF2) is also extremely important in determining the dose. Other factors are less influential since they vary less. 2. The variability of Ni (8 logs) is larger than the variation in cell number seen with gross disease (1 cm3 versus 1000 cm3, 3 logs). When Ni approximately 10(8), the required dose approaches that needed for small volume gross disease (10(9) cells, 1 cm3). 3. The dose prescribed to elective sites should reflect the risk of occult disease based on the primary tumor site, stage, and grade. 4. Regions where clinicoradiologic evaluation is difficult (e.g., pelvis and obese neck) require higher doses because macroscopic tumor deposits may exist. 5. Relatively low doses (10 to 30 Gy) are often thought to be inadequate for microscopic tumor. However, similar doses have been reported to sterilize microscopic tumor in ovarian, rectal, bladder, breast, and head and neck carcinomas. Relatively low doses should not be discounted since they may be useful in select cases when normal tissue tolerances and/or previous irradiation treatment limit the radiation dose.

Marks, L.B. (Duke Univ. Medical Center, Durham, NC (USA))

1990-12-15T23:59:59.000Z

226

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

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Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect Melvyn Folkard Gray Cancer Institute Why This Project The aim of this project is to determine the effects of low radiation doses using a machine that makes it possible to radiate one cell at a time. Our soft X-ray microprobe can irradiate individual cells, or locations within cells with defined doses and with sub-micron precision. We can use low doses approaching that of a single electron track, which is of relevance to environmental level exposures. Much of our work is concentrating on irradiating specified individual cells within cell populations to identify "bystander responses" where non-radiated cells respond to signals from nearby radiated cells. Higher energy x-rays are being generated to extend

227

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

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a Low LET Electron Microbeam to Investigate Non-Targeted Effects of a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation William F. Morgan Radiation Oncology Research Laboratory, Pacific Northwest National Laboratory Why this Project? To examine genomic instability and bystander effects as non-targeted effects associated with low dose radiation exposure. Project Goals To provides a robust, reliable, highly sensitive assay for detecting delayed events occurring in cells exposed to low doses of ionizing radiation. Experimental Approach To mimic radiation damage from gamma and x-ray sources, a low-LET electron microbeam that generates energetic electrons has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells leaving neighboring cells unirradiated. Using a novel green fluorescence gene (GFP) reporter assay, a high through

228

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary  

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Genetic susceptibility to low-dose ionizing radiation in the mouse mammary Genetic susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders Lawrence Berkeley National Laboratory Abstract Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer. Background and Significance: It is increasingly believed that individuals differ in their genetic susceptibilities to environmental insults for diseases such as cancer. This concern is especially important for the large numbers of individuals receiving low-dose exposures in the nuclear energy

229

Low Dose Radiation Research Program: Howard L. Liber  

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Howard L. Liber Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Currently Funded Projects Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Technical Abstracts 2003 Workshop: Delayed genomic instability in human lymphoblasts exposed to 137Cs y-rays radiation Schwartz, J.L., Jordan, R., Lenarczyk, M. and Liber, H.L. 2002 Workshop: Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells. Liber, H.L. and Schwartz, J.L. Publications Zhang, Y., Zhou, J., Held, K.D., Redmond, R.W., Prise, K.M., and Liber, H.L. (2008). Deficiencies of double-strand break repair factors and effects on mutagenesis in directly [gamma]-irradiated and medium-mediated bystander human lymphoblastoid cells. Radiation Research 169(2):197-206.

230

Low Dose Radiation Program: Links - Current Issues Involving...  

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of Ionizing Radiation A-Bombs Atomicarchive.com Hiroshima Peace site History of the Atomic Bomb & The Manhattan Project The Atomic Testing Museum The Race to Build the Atomic...

231

Low Dose Radiation Research Program: Gregory A. Kimmel  

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Gregory A. Kimmel Gregory A. Kimmel Pacific Northwest National Laboratory Past Project A Novel Spatially Resolved Cell Irradiator to Study Bystander and Adaptive Responses to Low-LET Radiation. Technical Abstracts 2002 Workshop: Spatially Resolved Single Cell Irradiator to Study Bystander Responses to Low LET Radiation. Resat, M.S., Kimmel, G.A., Miller, J.H., McDonald, J.C., Murphy, M.K., Strom, D.J., Thrall, B.D., and Colson, S.D. 2001 Workshop: Spatially Resolved Single Cell Irradiator to Study Bystander Responses to Low LET Radiation. Resat, M.S., Kimmel, G.A., Miller, J.H., McDonald, J.C., Murphy, M.K., Strom, D.J., Thrall, B.D., Metting, N.F., and Colson, S.D 1999 Workshop: A Novel, Spatially Resolved Cell Irradiator to Study Bystander and Adaptive Responses to Low-LET Radiation.

232

An integrated genetics approach to systemic low-dose radiation...  

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mammary tumor formation by combining our genetic diverse mouse model with the mammary gland radiation chimera model pioneered in the Barcellos-Hoff laboratory (3,4). As it takes...

233

Low Dose Radiation Research Program: Delayed Genomic Instability...  

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Lymphoblasts Exposed to 137Cs y-rays Radiation Authors: Jeffrey L. Schwartzb, Robert Jordan,b, Marek Lenarczyk,a and Howard L. Libera Institutions: a Department of Environmental...

234

Annual report shows potential INL radiation doses well below...  

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than 1% of the limit of 10 mrem established by the EPA and is about 2% of the amount of radiation a person receives during a dental x-ray. In comparison, according to the U.S....

235

Low Dose Radiation Research Program: Monte Carlo Track Structure...  

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Monte Carlo Track Structure Simulations for Low-LET Selected Cell Radiation Studies Walt Wilson Washington State University Tri-Cities Why This Project There are many types of...

236

Effects of low-dose radiation on immune cell function using genetic and  

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low-dose radiation on immune cell function using genetic and low-dose radiation on immune cell function using genetic and metabolomics approaches Henghong Li Georgetown University Abstract The objectives of this study are to investigate acute and persistent effects of ionizing radiation and space radiation on immune cell subsets and function. The role(s) for p38 MAP kinase in such radiation responses is being investigated using a genetic approach where an engineered mouse line has had one wt p38α gene replaced with a dominantnegative mutant (p38α+/DN). T cells are one of the most radiosensitive cell types in vivo, and radiation is known to impact CD4 T cell function long term. T cells are normally activated by antigen, which triggers differentiation to specific subsets involving various cytokines. In addition, T cells have a

237

Low Dose Radiation Research Program: Impact of Genetic Factors on the  

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Genetic Factors on the Heritable Effects of Paternal Exposure to Genetic Factors on the Heritable Effects of Paternal Exposure to Low-Dose Radiation Janet E. Baulch University of California, Davis Why This Project? There is concern about the possible genetic effects of low dose radiation exposure. As a result, much effort has gone towards understanding mutation of cells due to radiation exposure. While recognition of the potential for mutation from exposure to ionizing radiation has led to extensive research, less effort has been given to the possible delayed risk of radiation exposure transmitted to the offspring of the exposed parent. Data from animal models show that parental exposures to DNA-damaging agents, such as ionizing radiation, predispose the offspring to serious health effects, including cancer offspring. Additionally, data from both humans and animal

238

Radiation and litigation : analyses of the ALARA principle and low dose radiation in the courts, and the future of radiation in court cases  

E-Print Network (OSTI)

Currently there are a growing number of radiation workers. In order to ensure the safety of the employees, regulations have been established by the federal government and state governments to limit the dose equivalent to ...

Esparza, Enrique

2006-01-01T23:59:59.000Z

239

Low Dose Radiation Research Program: Studies of Low-Dose Bystander...  

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Low-Dose Bystander Effects Using a Focused Soft X-ray Microprobe Kevin M. Prise1, Melvyn Folkard1, Giuseppe Schettino1, Elena Rusyn2, Heidi C. Newman1, Kathryn D. Held2 and Barry...

240

Environmental Radiation Doses From Difficult-to-Measure Nuclides  

Science Conference Proceedings (OSTI)

Nuclear power plants release numerous radionuclides to the environment, but evaluating the significance of the environmental dose from these nuclides is difficult. The simplified methodology developed in this research makes this assessment easier and can also help environmental engineers design appropriate monitoring programs.

1985-01-14T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Low Dose Radiation Research Program: Modeling Intercellular Interactions  

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Modeling Intercellular Interactions During Radiation Carcinogenesis Modeling Intercellular Interactions During Radiation Carcinogenesis Authors: Rainer K Sachs,1 Michael Chan,2 Lynn Hlatky,3 Philip Hahnfeldt3 Institutions: 1Departments of Mathematics and Physics, University of California Berkeley California; 2School of Medicine, University of California at San Diego, La Jolla California; 3Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston Massachusetts Abstract By modulating the microenvironment of malignant or pre-malignant epithelial cells, inhibitory or stimulatory signals from nearby cells, including those in stromal and vascular tissues, can play a key role in carcinogenesis; cancer is ultimately a disease of a whole-cell community, not just of a single cell, clone, or cell lineage. However, current commonly used

242

Low Dose Radiation Program: Links - Suggested Books and Literature for  

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Suggested Books and Literature for Teachers about Radiation Suggested Books and Literature for Teachers about Radiation Popular Press News Articles Newspapers is an excellent portal or gateway to newspapers from all 50 states. To find a newspaper of interest, select a state and click Search. For a more specified search, fill in the Title of the newspaper and click Search. The newspapers available from that state are listed alphabetically. Hall, E., Radiation and Life Hall, E.J.Radiobiology for the Radiologist. 5th ed. Lippincott Williams & Wilkins, Philadelphia, PA. 2000 Nagai, T.Atomic Bomb Rescue and Relief Report. Nagasaki Association for Hibakushas' Medical Care (NASHIM), Nagasaki, Japan. 2000 Nagataki, S.Nagasaki Symposium on Chernobyl: Update and Future, Proceedings of "Chernobyl Update" 3 June 1994 at the 67th Annual Meeting of

243

Low Dose Radiation Research Program: Interaction between Tissue and  

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between Tissue and Cellular Stress Responses: Effect of between Tissue and Cellular Stress Responses: Effect of TGF-ß Depletion on Radiation-Induced p53 Response M.H. Barcellos-Hoff, S.A. Ravani, R.L. Henshall, K.B. Ewan, R.L. Warters,* B. Parvin Lawrence Berkeley National Laboratory *University of Utah One of the most widely studied cellular responses to radiation is the activation of the transcription factor, p53, whose abundance and action dictates individual cellular fate decisions regarding proliferation, differentiation and death. A cell's response to damage needs to be rapid. Thus, it is not surprising that the activation of the p53 stress response primarily involves post-translational changes in the p53 protein. Whereas intracellular radiation-induced mediators of p53 stability have been the subject of intense study, little is known about the extracellular factors

244

Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation.  

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Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation. Thomas J. Annexin A2 Regulates A Low Dose-Specific Stress Response To Radiation. Thomas J. Weber (PI), Greg J. Newton, Ryan D. Quesenberry, Janani I. Shutthanandan, Nikki Bollinger, Heather E. Engelmann and Lee K. Opresko. Cell Biology and Biochemistry Group, Pacific Northwest National Laboratory, Richland, WA 99354. Previous studies have demonstrated that JB6 cells release cell transforming paracrine factors following exposure to a low dose of radiation (10 cGy). Investigation of secreted proteins by SDS-Page and silver stain led to the identification of a 36 kDa band whose levels were increased in medium from irradiated cells, relative to sham controls. The 36 kDa band was identified as annexin A2 by mass spectrometry. Western blot analysis confirmed a dose-dependent increase in annexin A2 levels associated with medium from

245

Cellular response to low dose radiation: Role of phosphatidylinositol-3 kinase like kinases  

Science Conference Proceedings (OSTI)

It is increasingly realized that human exposure either to an acute low dose or multiple chronic low doses of low LET radiation has the potential to cause different types of cancer. Therefore, the central theme of research for DOE and NASA is focused on understanding the molecular mechanisms and pathways responsible for the cellular response to low dose radiation which would not only improve the accuracy of estimating health risks but also help in the development of predictive assays for low dose radiation risks associated with tissue degeneration and cancer. The working hypothesis for this proposal is that the cellular mechanisms in terms of DNA damage signaling, repair and cell cycle checkpoint regulation are different for low and high doses of low LET radiation and that the mode of action of phosphatidylinositol-3 kinase like kinases (PIKK: ATM, ATR and DNA-PK) determines the dose dependent cellular responses. The hypothesis will be tested at two levels: (I) Evaluation of the role of ATM, ATR and DNA-PK in cellular response to low and high doses of low LET radiation in simple in vitro human cell systems and (II) Determination of radiation responses in complex cell microenvironments such as human EpiDerm tissue constructs. Cellular responses to low and high doses of low LET radiation will be assessed from the view points of DNA damage signaling, DNA double strand break repair and cell cycle checkpoint regulation by analyzing the activities (i.e. post-translational modifications and kinetics of protein-protein interactions) of the key target proteins for PI-3 kinase like kinases both at the intra-cellular and molecular levels. The proteins chosen for this proposal are placed under three categories: (I) sensors/initiators include ATM ser1981, ATR, 53BP1, gamma-H2AX, MDC1, MRE11, Rad50 and Nbs1; (II) signal transducers include Chk1, Chk2, FANCD2 and SMC1; and (III) effectors include p53, CDC25A and CDC25C. The primary goal of this proposal is to elucidate the differences in cellular defense mechanisms between low and high doses of low LET radiation and to define the radiation doses where the cellular DNA damage signaling and repair mechanisms tend to shift. This information is critically important to address and advance some of the low dose research program objectives of DOE. The results of this proposed study will lead to a better understanding of the mechanisms for the cellular responses to low and high doses of low LET radiation. Further, systematic analysis of the role of PIKK signaling pathways as a function of radiation dose in tissue microenvironment will provide useful mechanistic information for improving the accuracy of radiation risk assessment for low doses. Knowledge of radiation responses in tissue microenvironment is important for the accurate prediction of ionizing radiation risks associated with cancer and tissue degeneration in humans.

Balajee, A.S.; Meador, J.A.; Su, Y.

2011-03-24T23:59:59.000Z

246

Low Dose Radiation Research Program: Interaction of Genome and Cellular  

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of Genome and Cellular Micronenvioronment of Genome and Cellular Micronenvioronment Mina Bissell Life Sciences Division Lawrence Berkeley National Laboratory Why this Project While normal stoma can delay or prevent tumorigenesis, abnormal stromal components can promote tumor growth. Acquired or inherited mutations that alter stromal cell function can release the context-suppressed malignant cells. Literature spanning more than a century has shown that inflammation associated with tissue wounding can produce tunors. Radiation produces changes in reactive oxygen that are similar to inflammation and may represent a mechanism for radiation-induced damage. Project Goals To determine the underlying role of stromal alterations in controling genomic instability accompanying epithelial-mesenchyumal transformation.

247

Low Dose Radiation Research Program: Mary Helen Barcellos-Hoff - 2003  

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DOE Low Dose Radiation Program Workshop IV DOE Low Dose Radiation Program Workshop IV Abstract Title: TGF-β Protects Human Mammary Epithelial Cells from Radiation-Induced Centrosome Amplification Authors: Mary Helen Barcellos-Hoff, Bahram Parvin, Anna C. Erickson and Rishi Gupta Institutions: Department of Cell and Molecular Biology, Life Sciences Division, Ernest Orlando Lawrence, Berkeley National Laboratory, Berkeley, California In recent studies we have shown that ionizing radiation (IR), a known carcinogen of human and murine mammary gland, compromises human mammary epithelial cell (HMEC) polarity and multicellular organization in a manner characteristic of neoplastic progression through a heritable, non-mutational mechanism (1). Thus, when all cells are irradiated with a significant dose (2 Gy), the daughters of irradiated cells lose their

248

Low Dose Radiation Research Program: Dual Regulation of JB6 Transformation  

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Dual Regulation of JB6 Transformation by Low Dose Gamma Radiation. Dual Regulation of JB6 Transformation by Low Dose Gamma Radiation. Authors: Thomas J. Weber,1 Lye M. Markillie,1 William B. Chrisler,1 Xingye C. Lei,1 and Nancy H. Colburn2 Institutions: 1Molecular Biosciences, Pacific Northwest National Laboratory. 2Gene Regulation Section, Basic Research Laboratory, National Cancer Institute JB6 mouse epidermal cells have been instrumental in defining the molecular mechanisms associated with neoplastic transformation in response to known tumor promoters. JB6 cells exhibit a clonal growth response to oxygen free radicals suggesting this model may also be useful for radiation research. Treatment of JB6 cells with 2 and 20 cGy gamma radiation resulted in a weak, but dose-dependent increase in anchorage-independent growth observed

249

Composite radiation dose representation using Fuzzy Set theory  

Science Conference Proceedings (OSTI)

Composite plans created from different image sets are generated through Deformable Image Registration (DIR) and present a challenge in accurately presenting uncertainties, which vary with anatomy. Our effort focuses on the application of Fuzzy Set theory ... Keywords: Composite plan, Deformable image registration, Fuzzy Set, Radiation therapy

Samuel B. Park; James I. Monroe; Min Yao; Mitchell Machtay; Jason W. Sohn

2012-03-01T23:59:59.000Z

250

ORIGINAL ARTICLE Biodistribution and radiation dosimetry of a positron  

E-Print Network (OSTI)

. Radiation-absorbed doses were estimated by the Medical Internal Radiation Dose scheme. Results After injecting 18 F-SP203, the two organs with highest radiation exposure were urinary bladder wallORIGINAL ARTICLE Biodistribution and radiation dosimetry of a positron emission tomographic ligand

Shen, Jun

251

What can be learned from epidemiologic studies of persons exposed to low doses of radiation?  

SciTech Connect

The main objective of radiation risk assessment is to determine the risk of various adverse health effects associated with exposure to low doses and low dose rates. Extrapolation of risks from studies of persons exposed at high doses (generally exceeding 1 Sv) and dose rates has been the primary approach used to achieve this objective. The study of Japanese atomic bomb survivors in Hiroshima and Nagasaki has played an especially important role in risk assessment efforts. A direct assessment of the dose-response function based on studies of persons exposed at low doses and dose rates is obviously desirable. This paper focuses on the potential of both current and future nuclear workers studies for investigating the dose-response functions at low doses, and also discusses analyses making use of the low dose portion of the atomic bomb survivor data. Difficulties in using these data are the statistical imprecision of estimated dose-response parameters, and potential bias resulting from confounding factors and from uncertainties in dose estimates.

Gilbert, E.S.

1993-04-01T23:59:59.000Z

252

Low-Dose Ionizing Radiation Alters the Epigenome of the Avy Mouse  

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Ionizing Radiation Alters the Epigenome of the A Ionizing Radiation Alters the Epigenome of the A vy Mouse Autumn Bernal 1,2,3 , Dale Huang 1 , Yue Li 4 , Dana Dolinoy 5 , and Randy Jirtle 1 Department of Radiation Oncology 1 , University Program in Genetics and Genomic 2 , Integrated Toxicology & Environmental Health Program 3 , Department of Community and Family Medicine 4 , Duke University Medical Center, Durham, NC, USA, Department of Environmental and Health Sciences, University of Michigan, Ann Arbor, MI, USA 4 Background: Humans have evolved and thrived amidst constant low-dose (0-10 cGy) background radiation exposure from natural sources. Currently, however, the frequency of exposures to low doses of radiation is increasing due to man-made sources such as diagnostic imaging and nuclear power. This increased exposure has led to concerns amongst the general public and the government about the

253

Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells.  

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Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation Mechanisms Underlying Cellular Responses to Low Doses/Low LET Ionizing Radiation in Primary Haemopoietic Cells. Munira Kadhim 1 , Stefania Militi 1 , Debbie Bowler 1 , Denise Macdonald 1 and Kevin Prise 2 1 Radiation and Genome Stability Unit, MRC, Harwell, Didcot, Oxon, OX11 0RD, UK 2 Gray Cancer Institute ,PO Box 100, Mount Vernon Hospital, Northwood, HA6 2JR, UK Because the human population is genetically heterogeneous, it is important to understand the role that heterogeneity may play in radiation response. Exposure to ionizing radiation can lead to a suite of changes, including increased mutation rate, delayed reproductive cell death, and delayed chromosomal aberrations, all of which are manifestations of the complex genomic instability (GI) phenotype. Following exposure to either high LET

254

Low Dose Radiation Research Program: Molecular Mechanisms of  

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Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Molecular Mechanisms of Radiation-Induced Genomic Instability in Human Cells Howard L. Liber Department of Environmental and Radiological Health Sciences Colorado State University Why This Project This research will be to investigate the condition known as genomic instability. This can be defined as a state in which genetic alterations, including chromosome aberrations and gene mutations, occur at rates that are much higher than normal. In fact, genomic instability is what allows a normal cell to accumulate the multiple genetic alterations that are required to convert it into a cancer cell. The chromosomes of human cells have structures at their ends called telomeres. Telomeres normally function to prevent chromosomes from fusing together end-to-end. An important

255

Low Dose Radiation Research Program: The Progeny of Irradiated Mammary  

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Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Progeny of Irradiated Mammary Epithelial Cells Exhibit a Phenotype Characteristic of Malignancy Mary H. Barcellos-Hoff, R.L. Henshall-Powell, M.J. Bissell, and B. Parvin Lawrence Berkeley National Laboratory, Life Sciences Division We have proposed that the ability of radiation to induce altered microenvironments affects the frequency and features of neoplastic progression. Thus, we have sought to characterize the irradiated microenvironment and determine how these events contribute to mammary carcinogenesis. By using imaging bioinformatics to analyze mouse and human models of breast cancer we have now examined cell adhesion molecules (CAMs) critical for tissue-specific organization and function. We found that 1) radiation-induced microenvironments can contribute to neoplastic potential

256

Low Dose Radiation Cancer Risks: Epidemiological and Toxicological Models  

Science Conference Proceedings (OSTI)

The basic purpose of this one year research grant was to extend the two stage clonal expansion model (TSCE) of carcinogenesis to exposures other than the usual single acute exposure. The two-stage clonal expansion model of carcinogenesis incorporates the biological process of carcinogenesis, which involves two mutations and the clonal proliferation of the intermediate cells, in a stochastic, mathematical way. The current TSCE model serves a general purpose of acute exposure models but requires numerical computation of both the survival and hazard functions. The primary objective of this research project was to develop the analytical expressions for the survival function and the hazard function of the occurrence of the first cancer cell for acute, continuous and multiple exposure cases within the framework of the piece-wise constant parameter two-stage clonal expansion model of carcinogenesis. For acute exposure and multiple exposures of acute series, it is either only allowed to have the first mutation rate vary with the dose, or to have all the parameters be dose dependent; for multiple exposures of continuous exposures, all the parameters are allowed to vary with the dose. With these analytical functions, it becomes easy to evaluate the risks of cancer and allows one to deal with the various exposure patterns in cancer risk assessment. A second objective was to apply the TSCE model with varing continuous exposures from the cancer studies of inhaled plutonium in beagle dogs. Using step functions to estimate the retention functions of the pulmonary exposure of plutonium the multiple exposure versions of the TSCE model was to be used to estimate the beagle dog lung cancer risks. The mathematical equations of the multiple exposure versions of the TSCE model were developed. A draft manuscript which is attached provides the results of this mathematical work. The application work using the beagle dog data from plutonium exposure has not been completed due to the fact that the research project did not continue beyond its first year.

David G. Hoel, PhD

2012-04-19T23:59:59.000Z

257

The Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays,  

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Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, Mechanism of Low Dose Radiation Risk Associated with Diagnostic X-rays, PET, and Gamma-rays Douglas Boreham McMaster University Abstract The goal of this project was to investigate low dose ionizing radiation effects associated with exposure to diagnostic computed tomography (CT) or positron emission tomography (PET) scans. Biological effects were evaluated in wild type and Trp53+/- heterozygous females, following in vivo exposure to diagnostic CT (75kVp, 200µ) or PET (18F-FDG) scans. The short term biological effects following CT or PET scans were evaluated in order to understand biological modification of mechanisms, such as DNA repair processes and apoptosis, that might alter long term cancer risk. Corresponding life-time cancer risk studies are in progress. Short-term

258

Low Dose Radiation Research Program: The Role of the Number and Spacing of  

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Program Workshop I Program Workshop I November 10-12, 1999, Washington, D.C. The Role of the Number and Spacing of Electron Tracks on the Consequences of Low Dose Irradiation Leslie A. Braby and J. R. Ford Nuclear Engineering, Texas A&M University, 129 Zachry, College Station, Texas. Summary: Biological mechanisms, which may influence the health risks resulting from very low dose radiation exposures, will be investigated using a collimated beam of electrons to simulate the irradiation patterns occurring with low dose exposures. Abstract: Ionizing radiation produces a variety of free radicals and chemical products that react to produce the same types of oxidative damage in a mammalian cell as produced by the normal metabolic activity of the cell. However, the damage produced by radiation is distributed differently

259

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells Proteomic and Biochemical Studies of Human Mesenchymal Stem Cells in Response to Low Dose Ionizing Radiation Deok-Jin Jang 1 , Mingquan Guo 1 , Julia S.F.Chu 2 , Kyle T. Kurpinski 2 , Bjorn Rydberg 1 , Song Li 2 , and Daojing Wang 1 1. Life Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720 2. Department of Bioengineering, University of California, Berkeley, CA 94720 We will present data obtained during the first year of our DOE/NASA Low Dose Radiation Research program. We utilized a comprehensive approach including transcriptomics, proteomics, phosphoproteomics, and biochemistry to characterize human mesenchymal stem cells (MSCs) in response to low dose ionizing radiation. We first determined the cell survival, proliferation, and osteogenic differentiation of

260

Investigation of non-targeted effects of low dose ionizing radiation on the mammary gland  

NLE Websites -- All DOE Office Websites (Extended Search)

non-targeted effects of low dose ionizing radiation on the mammary gland non-targeted effects of low dose ionizing radiation on the mammary gland utilizing three-dimensional culture models of mammary cells derived from mouse strains that differ in susceptibility to tumorigenesis Joni D. Mott, Antoine M. Snijders, Alvin Lo, Dinah Levy-Groesser, Bahram Parvin, Andrew J. Wyrobek, Jian-Hua Mao, and Mina J. Bissell Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley CA 94720 Goal: Within the Lawrence Berkeley National Laboratory's SFA, Project 2, our studies focus on utilizing three dimensional (3D) cell culture models as surrogates for in vivo studies to determine how low doses of ionizing radiation influence mammary gland tissue architecture and how this may relate both to tumor progression and/or adaptive response.

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Dosimetry in steep dose-rate gradient radiation fields: A challenge in clinical applications  

Science Conference Proceedings (OSTI)

The fundamental goal of radiotherapy is to reduce the damage to normal tissue and optimize the dose to the tumor with an associated high probability of cure. Because of this, an accurate and precise knowledge of the radiation dose distribution delivered around the tumor volume during radiotherapy treatments such as stereotactic radiosurgery, intensity modulated radiotherapy or brachytherapy with low-energy X-ray and beta particle sources is of great importance. However, in each of these radiation fields, there exists a steep dose-rate gradient which makes it very difficult to perform accurate dose measurements. In this work, the physics phenomena involved in the energy absorption for each of these situations are discussed, and a brief revision of what the Medical Physics community is doing is presented.

Massillon-JL, G. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, A.P. 20-364, 01000 DF (Mexico)

2010-12-07T23:59:59.000Z

262

Low Dose Radiation Research Program: Funded Project Descriptions  

NLE Websites -- All DOE Office Websites (Extended Search)

Funded Project Descriptions Funded Project Descriptions Non-Invasive Early Detection and Molecular Analysis of Low X-Ray Dose Effects in the Lens Jointly funded by NASA and DOE Principal Investigator: Lee Goldstein, M.D., Ph.D., Associate Professor in Psychiatry, Neurology, Ophthalmology, Pathology and Laboratory Medicine, & Biomedical Engineering, Boston University’s School Medicine, College of Engineering, and Photonics Center. Boston, Ma. The project includes a new DOE FWP (~$400 K over 3 years) to Lawrence Berkeley National Laboratory with Eleanor Blakely as Project Leader. The work includes a subcontract to support the collaboration of Polly Chang of SRI, International, Menlo Park, CA. and is scheduled to begin as early as August 2009. This proposal was submitted in response to the joint DOE/NASA

263

Mammalian Tissue Response to Low Dose Ionizing Radiation: The Role of Oxidative Metabolism and Intercellular Communication  

SciTech Connect

The objective of the project was to elucidate the mechanisms underlying the biological effects of low dose/low dose rate ionizing radiation in organs/tissues of irradiated mice that differ in their susceptibility to ionizing radiation, and in human cells grown under conditions that mimic the natural in vivo environment. The focus was on the effects of sparsely ionizing cesium-137 gamma rays and the role of oxidative metabolism and intercellular communication in these effects. Four Specific Aims were proposed. The integrated outcome of the experiments performed to investigate these aims has been significant towards developing a scientific basis to more accurately estimate human health risks from exposures to low doses ionizing radiation. By understanding the biochemical and molecular changes induced by low dose radiation, several novel markers associated with mitochondrial functions were identified, which has opened new avenues to investigate metabolic processes that may be affected by such exposure. In particular, a sensitive biomarker that is differentially modulated by low and high dose gamma rays was discovered.

Azzam, Edouard I

2013-01-16T23:59:59.000Z

264

Low Dose Radiation Research Program: Quantitative Analysis of Connexin  

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Quantitative Analysis of Connexin Expression in Cultured Colonies Quantitative Analysis of Connexin Expression in Cultured Colonies Authors: B. Parvin, Q. Yang, R. L. Henshall-Powell and M.H. Barcellos Hoff We are studying the effects of ionizing radiation on the signaling between human mammary epithelial cells and the extracellular microenvironment. To do so we use an assay based on the ability of the cells to organize into three-dimensional acini when embedded into an extracellular matrix. Although tumorigenic and non-tumorigenic mammary epithelial cells are nearly indistinguishable when cultured as monolayers, their biological character readily diverge when tissue-specific morphogenesis is analyzed. Non-malignant human mammary epithelial cells (HMEC) cultured within a reconstituted basement membrane organize into acinar-like structures with

265

Low Dose Radiation Research Program: Research Highlights - Real-time  

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Real-time imaging of repair processes possible with Nickel-63 Real-time imaging of repair processes possible with Nickel-63 microirradiator Microscope Microscope stage-mounted microirradiation system. (A) Overall system shown mounted on a micromanipulator housed within a heated, humidified, environmental chamber of a microscope. (B) Close-up showing attachment of device to the micromanipulator. (C) Detail showing the bend in the enclosing capillary, which allows positioning of the active surface directly above the target cell. (D) Microirradiator tip in dissecting microscope. (E) Close-up view through microscope optics (scale bar, 10 microns.) Background: Scientists know that mammalian cells begin a nucleoplasmic repair process within seconds after being exposed to ionizing radiation. Real-time imaging of this process could further understanding of the

266

An integrated genetics approach to systemic low-dose radiation responses  

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integrated genetics approach to systemic low-dose radiation responses integrated genetics approach to systemic low-dose radiation responses G. Huang 1 , Y. Huang 1 , D.H. Nguyen 1 , K. Bjornstad 1 , C. Rosen 1 , P. Chang 2 , R. DelRosario 3 , Do Yup Lee 1 , B. Bowen 1 , W. Reindl 1 , J. Mott 1 , A. Balmain 3 , M.H. Barcellos-Hoff 4 , Joe W Gray 1,5 , Mina Bissell 1 , Gary Karpen 1 , T. Northen 1 , E. A. Blakely 1 , J. H. Mao 1 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 2 SRI International, Menlo Park, CA

267

Low Dose Radiation Research Program: Using a Low LET Electron Microbeam to  

NLE Websites -- All DOE Office Websites (Extended Search)

Using a Low LET Electron Microbeam to Investigate Non-Targeted Using a Low LET Electron Microbeam to Investigate Non-Targeted Effects of Low Dose Radiation Authors: William F. Morgan1 and Marianne B. Sowa2 Institutions: 1Radiation Oncology Research Laboratory, University of Maryland, Baltimore, Maryland; 2Chemical Structure and Dynamics, Pacific Northwest National Laboratory, Richland Washington We have recently installed a low-linear energy transfer (LET) electron microbeam that generates energetic electrons to mimic radiation damage from gamma- and x-ray sources. It has been designed such that high-energy electrons deposit energy in a pre-selected subset of cells, leaving neighboring cells unirradiated (Figure 1). In this way it is possible to examine non-targeted effects associated with low dose radiation exposure,

268

Low Dose Radiation Research Program: Role of TNF-α as a Potential  

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Role of TNF-α as a Potential Signaling Mediator of Role of TNF-α as a Potential Signaling Mediator of Radiation-Induced Bystander Effect in Human Vascular Cells. Authors: Mohan Natarajan, Sumathy Mohan, Catherine Gibbons, Yan Bo and Munira A. Kadhim Institutions: Departments of Radiation Oncology and Pathology, University of Texas Health Science Center, San Antonio, Texas; Environmental Toxicology Graduate Program, University of California, Riverside; Radiation and Genomic Stability Unit, Medical research Council, Oxford, United Kingdom Identifying reliable and sensitive signaling pathways that are implicated in adverse health effects after exposure to low doses of ionizing radiation would allow us to understand the scientific basis of low dose-induced signaling pathways and their downstream phenotypic expression. This

269

Low Dose Radiation Research Program: Wide Expression of LLIR and the  

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Wide Expression of LLIR and the Biological Consequences Wide Expression of LLIR and the Biological Consequences David J. Chen Lawrence Berkeley National Laboratory Why This Project It is known that changes in gene expression alter biological effects. It is necessary to identify the specific genes that demonstrate altered expression after exposure to low doses of ionizing radiation and to determine pathways involved in DNA damage recognition, signaling, and repair that are associated with radiation-induced adaptive and bystander effects. Project Goals Identification of genes whose transcription is regulated in response to low levels of ionizing radiation Identification of the genes and communication pathways that control these responses to low dose radiation Identification of the cellular and molecular targets that influence

270

Radiosensitization of Human Cervical Cancer Cells by Inhibiting Ribonucleotide Reductase: Enhanced Radiation Response at Low-Dose Rates  

Science Conference Proceedings (OSTI)

Purpose: To test whether pharmacologic inhibition of ribonucleotide reductase (RNR) by 3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, NSC no. 663249) enhances radiation sensitivity during low-dose-rate ionizing radiation provided by a novel purpose-built iridium-192 cell irradiator. Methods and Materials: The cells were exposed to low-dose-rate radiation (11, 23, 37, 67 cGy/h) using a custom-fabricated cell irradiator or to high-dose-rate radiation (330 cGy/min) using a conventional cell irradiator. The radiation sensitivity of human cervical (CaSki, C33-a) cancer cells with or without RNR inhibition by 3-AP was evaluated using a clonogenic survival and an RNR activity assay. Alteration in the cell cycle distribution was monitored using flow cytometry. Results: Increasing radiation sensitivity of both CaSki and C33-a cells was observed with the incremental increase in radiation dose rates. 3-AP treatment led to enhanced radiation sensitivity in both cell lines, eliminating differences in cell cytotoxicity from the radiation dose rate. RNR blockade by 3-AP during low-dose-rate irradiation was associated with low RNR activity and extended G{sub 1}-phase cell cycle arrest. Conclusions: We conclude that RNR inhibition by 3-AP impedes DNA damage repair mechanisms that rely on deoxyribonucleotide production and thereby increases radiation sensitivity of human cervical cancers to low-dose-rate radiation.

Kunos, Charles A., E-mail: charles.kunos@UHhospitals.org [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Colussi, Valdir C. [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Pink, John [Department of General Medical Sciences, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Radivoyevitch, Tomas [Department of Epidemiology and Biostatistics, Case Comprehensive Cancer Center, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States); Oleinick, Nancy L. [Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve School of Medicine, Cleveland, OH (United States)

2011-07-15T23:59:59.000Z

271

Low dose radiation hypersensitivity and clustered DNA damages in human fibroblasts exposed to low dose and dose rate protons or 137CS y-rays  

SciTech Connect

Effective radioprotection for human space travelers hinges upon understanding the individual properties of charged particles. A significant fraction of particle radiation astronauts will encounter in space exploratory missions will come from high energy protons in galactic cosmic radiation (GCR) and/or possible exposures to lower energy proton flux from solar particle events (SPEs). These potential exposures present major concerns for NASA and others, in planning and executing long term space exploratory missions. We recently reported cell survival and transformation (acquisition of anchorage-independent growth in soft agar) frequencies in apparently normal NFF-28 primary human fibroblasts exposed to 0-30 cGy of 50MeV, 100MeV (SPE-like), or 1000 MeV (GCR-like) monoenergetic protons. These were modeled after 1989 SPE energies at an SPE-like low dose-rate (LDR) of 1.65 cGy/min or high dose rate (HDR) of 33.3 cGy/min delivered at the NASA Space Radiation Laboratory (NSRL) at BNL.

Bennett P. V.; Bennett, P.V.; Keszenman, D.J.; Johnson, A.M.; Sutherland, B.M.; Wilson, P.F.

2013-05-14T23:59:59.000Z

272

Review and Evaluation of Updated Research on the Health Effects Associated with Low-Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

Potential health effects of low levels of radiation have predominantly been based on those effects observed at high levels of radiation. The authors have reviewed more than 200 percent publications in radiobiology and epidermiology related to low dose radiation and concluded that recent radiobiological studies at low-doses; that doses low dose radiation research should to holistic, systems-based approaches to develop models that define the shape of the dose-response relationships at low doses; and that these results should be combined with the latest epidermiology to produce a comprehensive understanding of radiation effects that addresses both damage, likely with a linear effect, and response, possibly with non-linear consequences.

Dauer, Lawrence T.; Brooks, Antone L.; Hoel, David G.; Morgan, William F.; Stram, Daniel; Tran, Phung

2010-07-01T23:59:59.000Z

273

Mechanisms of Low Dose Radiation-induced T helper Cell Function  

SciTech Connect

Exposure to radiation above levels normally encountered on Earth can occur during wartime, accidents such as those at Three Mile Island and Chernobyl, and detonation of dirty bombs by terrorists. Relatively high levels of radiation exposure can also occur in certain occupations (low-level waste sites, nuclear power plants, nuclear medicine facilities, airline industry, and space agencies). Depression or dysfunction of the highly radiosensitive cells of the immune system can lead to serious consequences, including increased risk for infections, cancer, hypersensitivity reactions, poor wound healing, and other pathologies. The focus of this research was on the T helper (Th) subset of lymphocytes that secrete cytokines (proteins), and thus control many actions and interactions of other cell types that make up what is collectively known as the immune system. The Department of Energy (DOE) Low Dose Radiation Program is concerned with mechanisms altered by exposure to high energy photons (x- and gamma-rays), protons and electrons. This study compared, for the first time, the low-dose effects of two of these radiation forms, photons and protons, on the response of Th cells, as well as other cell types with which they communicate. The research provided insights regarding gene expression patterns and capacity to secrete potent immunostimulatory and immunosuppressive cytokines, some of which are implicated in pathophysiological processes. Furthermore, the photon versus proton comparison was important not only to healthy individuals who may be exposed, but also to patients undergoing radiotherapy, since many medical centers in the United States, as well as worldwide, are now building proton accelerators. The overall hypothesis of this study was that whole-body exposure to low-dose photons (gamma-rays) will alter CD4+ Th cell function. We further proposed that exposure to low-dose proton radiation will induce a different pattern of gene and functional changes compared to photons. Over the course of this research, tissues other than spleens were archived and with funding obtained from other sources, including the Department of Radiation Medicine at the Loma Linda University Medical Center, some additional assays were performed. Furthermore, groups of additional mice were included that were pre-exposed to low-dose photons before irradiating with acute photons, protons, and simulated solar particle event (SPE) protons. Hence, the original support together with the additional funding for our research led to generation of much valuable information that was originally not anticipated. Some of the data has already resulted in published articles, manuscripts in review, and a number of presentations at scientific conferences and workshops. Difficulties in reliable and reproducible quantification of secreted cytokines using multi-plex technology delayed completion of this study for a period of time. However, final analyses of the remaining data are currently being performed and should result in additional publications and presentations in the near future. Some of the most notable conclusions, thus far, are briefly summarized below: - Distribution of leukocytes were dependent upon cell type, radiation quality, body compartment analyzed, and time after exposure. Low-dose protons tended to have less effect on numbers of major leukocyte populations and T cell subsets compared to low-dose photons. - The patterns of gene and cytokine expression in CD4+ T cells after protracted low-dose irradiation were significantly modified and highly dependent upon the total dose and time after exposure. - Patterns of gene and cytokine expression differed substantially among groups exposed to low-dose photons versus low-dose protons; differences were also noted among groups exposed to much higher doses of photons, protons, and simulated SPE protons. - Some measurements indicated that exposure to low-dose photon radiation, especially 0.01 Gy, significantly normalized at least some adverse effects of simulated SPE protons, thereby suggesting that this l

Gridley, Daila S.

2008-10-31T23:59:59.000Z

274

Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation  

SciTech Connect

FINAL TECHNICAL REPORT Supported by the Low Dose Radiation Research Program, Office of Science U.S. Department of Energy Grant No. DE-FG02-07ER64345 Project ID: 0012965 Award Register#: ER64345 Project Manager: Noelle F. Metting, Sc.D. Phone: 301-903-8309 Division SC-23.2 noelle.metting@science.doe.gov Submitted March 2012 To: https://www.osti.gov/elink/241.3.jsp Title: Th Cell Gene Expression and Function in Response to Low Dose and Acute Radiation PI: Daila S. Gridley, Ph.D. Human low dose radiation data have been derived primarily from studies of space and airline flight personnel, nuclear plant workers and others exposed occupationally, as well as victims in the vicinity of atomic bomb explosions. The findings remain inconclusive due to population inconsistencies and complex interactions among total dose, dose rate, radiation quality and age at exposure. Thus, safe limits for low dose occupational irradiation are currently based on data obtained with doses far exceeding the levels expected for the general population and health risks have been largely extrapolated using the linear-nonthreshold dose-response model. The overall working hypothesis of the present study is that priming with low dose, low-linear energy transfer (LET) radiation can ameliorate the response to acute high-dose radiation exposure. We also propose that the efficacy of low-dose induced protection will be dependent upon the form and regimen of the high-dose exposure: photons versus protons versus simulated solar particle event protons (sSPE). The emphasis has been on gene expression and function of CD4+ T helper (Th) lymphocytes harvested from spleens of whole-body irradiated C57BL/6 mice, a strain that provides the genetic background for many genetically engineered strains. Evaluations of the responses of other selected cells, tissues such as skin, and organs such as lung, liver and brain were also initiated (partially funded by other sources). The long-term goal is to provide information that will be useful in estimating human health risks due to radiation that may occur during exposures in the work environment, nuclear/radiological catastrophes, as well as radiotherapy. Several papers have been published, accepted for publication or are in preparation. A number of poster and oral presentations have been made at scientific conferences and workshops. Archived tissues of various types will continue to be evaluated via funding from other sources (the DoE Low Dose Radiation Research Program, Office of Science and this specific grant will be appropriately included in the Acknowledgements of all subsequent publications/presentations). A post-doc and several students have participated in this study. More detailed description of the accomplishments is described in attached file.

Daila S. Gridley, PhD

2012-03-30T23:59:59.000Z

275

A PORTABLE DOSE RATE INSTRUMENT FOR MEASUREMENT OF NATURAL BACK-GROUND RADIATION LEVELS  

SciTech Connect

An instrument of the ionization chamber type which is capable of measuring radiation dose rates down to and below those encountered in natural background was designed and constructed. It consists of a 40-liter ionization chamber coupled to a portable battery-powered electrometer. The chamber polarizing battery is a part of the chamber center electrode assembly and is located inside the chamber. (auth)

Rising, F.L.

1960-12-19T23:59:59.000Z

276

Molecular Mechanisms of Low Dose Radiation Mediated Hormesis in C. elegans  

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Mechanisms of Low Dose Radiation Mediated Hormesis in C. Mechanisms of Low Dose Radiation Mediated Hormesis in C. elegans Anders Olsen, Maithili C. Vantipalli, Arnold Kahn, Judith Campisi and Gordon J. Lithgow. Buck Institute for Age Research, 8001 Redwood Boulevard, Novato CA 94945 Brief exposure to a mild stress causes induction of stress gene expression leading to enhanced stress responses, improved maintenance and repair and in some cases lifespan increase. This phenomenon is termed hormesis and has been observed in several species. For example, we previously demonstrated that short periods of mild heat stress in early life increase both mean and maximum lifespan of the soil nematode C. elegans. Similar hormetic responses have been described for many other stressors. Here we present data showing that treatment of the nematode with low-doses of ionizing

277

Low Dose Radiation Research Program: Genetic Control of Repair and Adaptive  

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Repair and Adaptive Responses to Low-level DNA Damage Repair and Adaptive Responses to Low-level DNA Damage James E. Haber Brandeis University Why This Project In order to fully understand mechanisms resulting in effects of low dose, whole system rather than cells must be examined. Although not identical to mammalian systems, simple systems usually have many similarities and give direction for further study of more complex systems. We use the budding yeast, Saccharomyces cerevisiae, as a model system because it is easy to manipulate and its genome is simple and well characterized. Project Goals Examine mechanisms and effects of low dose radiation response for: Genetic recombination mechanisms that lead to genomic instability Genetic factors that affect individual susceptibility to low-dose radiation The adaptive response

278

Low Dose Radiation Research Program: Mechanisms of Tissue Response to Low  

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Tissue Response to Low Dose Radiation Tissue Response to Low Dose Radiation Mary Helen Barcellos-Hoff Lawrence Berkeley National Laboratory Why This Project? In the past, the effects of ionizing radiation on humans has been attributed in great part to its ability to damage DNA, which transmits information from cell to cell, and generation to generation. Damaged DNA can lead to cell death or perpetuate the damage to daughter cells and to future generations. In addition to the information contained with the genome (i.e., DNA sequence), information directing cell behavior and tissue function is also stored outside the DNA. The success in cloning sheep from the DNA contained in the nucleus of an adult cell shows how important signals from the outside are in defining how the genome is expressed. This

279

Dose Constraints to Prevent Radiation-Induced Brachial Plexopathy in Patients Treated for Lung Cancer  

Science Conference Proceedings (OSTI)

Purpose: As the recommended radiation dose for non-small-cell lung cancer (NSCLC) increases, meeting dose constraints for critical structures like the brachial plexus becomes increasingly challenging, particularly for tumors in the superior sulcus. In this retrospective analysis, we compared dose-volume histogram information with the incidence of plexopathy to establish the maximum dose tolerated by the brachial plexus. Methods and Materials: We identified 90 patients with NSCLC treated with definitive chemoradiation from March 2007 through September 2010, who had received >55 Gy to the brachial plexus. We used a multiatlas segmentation method combined with deformable image registration to delineate the brachial plexus on the original planning CT scans and scored plexopathy according to Common Terminology Criteria for Adverse Events version 4.03. Results: Median radiation dose to the brachial plexus was 70 Gy (range, 56-87.5 Gy; 1.5-2.5 Gy/fraction). At a median follow-up time of 14.0 months, 14 patients (16%) had brachial plexopathy (8 patients [9%] had Grade 1, and 6 patients [7%] had Grade {>=}2); median time to symptom onset was 6.5 months (range, 1.4-37.4 months). On multivariate analysis, receipt of a median brachial plexus dose of >69 Gy (odds ratio [OR] 10.091; 95% confidence interval [CI], 1.512-67.331; p = 0.005), a maximum dose of >75 Gy to 2 cm{sup 3} of the brachial plexus (OR, 4.909; 95% CI, 0.966-24.952; p = 0.038), and the presence of plexopathy before irradiation (OR, 4.722; 95% CI, 1.267-17.606; p = 0.021) were independent predictors of brachial plexopathy. Conclusions: For lung cancers near the apical region, brachial plexopathy is a major concern for high-dose radiation therapy. We developed a computer-assisted image segmentation method that allows us to rapidly and consistently contour the brachial plexus and establish the dose limits to minimize the risk of brachial plexopathy. Our results could be used as a guideline in future prospective trials with high-dose radiation therapy for unresectable lung cancer.

Amini, Arya [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); University of California Irvine School of Medicine, Irvine, California (United States); Yang Jinzhong; Williamson, Ryan [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); McBurney, Michelle L. [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Erasmus, Jeremy [Department of Diagnostic Imaging, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Allen, Pamela K.; Karhade, Mandar; Komaki, Ritsuko; Liao, Zhongxing; Gomez, Daniel; Cox, James [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Dong, Lei [Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Welsh, James, E-mail: jwelsh@mdanderson.org [Department of Radiation Oncology, University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

2012-03-01T23:59:59.000Z

280

Patient-specific radiation dose and cancer risk estimation in CT: Part II. Application to patients  

SciTech Connect

Purpose: Current methods for estimating and reporting radiation dose from CT examinations are largely patient-generic; the body size and hence dose variation from patient to patient is not reflected. Furthermore, the current protocol designs rely on dose as a surrogate for the risk of cancer incidence, neglecting the strong dependence of risk on age and gender. The purpose of this study was to develop a method for estimating patient-specific radiation dose and cancer risk from CT examinations. Methods: The study included two patients (a 5-week-old female patient and a 12-year-old male patient), who underwent 64-slice CT examinations (LightSpeed VCT, GE Healthcare) of the chest, abdomen, and pelvis at our institution in 2006. For each patient, a nonuniform rational B-spine (NURBS) based full-body computer model was created based on the patient's clinical CT data. Large organs and structures inside the image volume were individually segmented and modeled. Other organs were created by transforming an existing adult male or female full-body computer model (developed from visible human data) to match the framework defined by the segmented organs, referencing the organ volume and anthropometry data in ICRP Publication 89. A Monte Carlo program previously developed and validated for dose simulation on the LightSpeed VCT scanner was used to estimate patient-specific organ dose, from which effective dose and risks of cancer incidence were derived. Patient-specific organ dose and effective dose were compared with patient-generic CT dose quantities in current clinical use: the volume-weighted CT dose index (CTDI{sub vol}) and the effective dose derived from the dose-length product (DLP). Results: The effective dose for the CT examination of the newborn patient (5.7 mSv) was higher but comparable to that for the CT examination of the teenager patient (4.9 mSv) due to the size-based clinical CT protocols at our institution, which employ lower scan techniques for smaller patients. However, the overall risk of cancer incidence attributable to the CT examination was much higher for the newborn (2.4 in 1000) than for the teenager (0.7 in 1000). For the two pediatric-aged patients in our study, CTDI{sub vol} underestimated dose to large organs in the scan coverage by 30%-48%. The effective dose derived from DLP using published conversion coefficients differed from that calculated using patient-specific organ dose values by -57% to 13%, when the tissue weighting factors of ICRP 60 were used, and by -63% to 28%, when the tissue weighting factors of ICRP 103 were used. Conclusions: It is possible to estimate patient-specific radiation dose and cancer risk from CT examinations by combining a validated Monte Carlo program with patient-specific anatomical models that are derived from the patients' clinical CT data and supplemented by transformed models of reference adults. With the construction of a large library of patient-specific computer models encompassing patients of all ages and weight percentiles, dose and risk can be estimated for any patient prior to or after a CT examination. Such information may aid in decisions for image utilization and can further guide the design and optimization of CT technologies and scan protocols.

Li Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Toncheva, Greta; Yoshizumi, Terry T.; Frush, Donald P. [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Medical Physics Graduate Program, Department of Physics, and Department of Biomedical Engineering, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 and Department of Biomedical Engineering, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Duke Radiation Dosimetry Laboratory, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Duke Radiation Dosimetry Laboratory, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Division of Pediatric Radiology, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27710 (United States)

2011-01-15T23:59:59.000Z

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281

Virtual monochromatic imaging in dual-source dual-energy CT: Radiation dose and image quality  

Science Conference Proceedings (OSTI)

Purpose: To evaluate the image quality of virtual monochromatic images synthesized from dual-source dual-energy computed tomography (CT) in comparison with conventional polychromatic single-energy CT for the same radiation dose. Methods: In dual-energy CT, besides the material-specific information, one may also synthesize monochromatic images at different energies, which can be used for routine diagnosis similar to conventional polychromatic single-energy images. In this work, the authors assessed whether virtual monochromatic images generated from dual-source CT scanners had an image quality similar to that of polychromatic single-energy images for the same radiation dose. First, the authors provided a theoretical analysis of the optimal monochromatic energy for either the minimum noise level or the highest iodine contrast to noise ratio (CNR) for a given patient size and dose partitioning between the low- and high-energy scans. Second, the authors performed an experimental study on a dual-source CT scanner to evaluate the noise and iodine CNR in monochromatic images. A thoracic phantom with three sizes of attenuating rings was used to represent four adult sizes. For each phantom size, three dose partitionings between the low-energy (80 kV) and the high-energy (140 kV) scans were used in the dual-energy scan. Monochromatic images at eight energies (40 to 110 keV) were generated for each scan. Phantoms were also scanned at each of the four polychromatic single energy (80, 100, 120, and 140 kV) with the same radiation dose. Results: The optimal virtual monochromatic energy depends on several factors: phantom size, partitioning of the radiation dose between low- and high-energy scans, and the image quality metrics to be optimized. With the increase of phantom size, the optimal monochromatic energy increased. With the increased percentage of radiation dose on the low energy scan, the optimal monochromatic energy decreased. When maximizing the iodine CNR in monochromatic images, the optimal energy was lower than that when minimizing noise level. When the total radiation dose was equally distributed between low and high energy in dual-energy scans, for minimum noise, the optimal energies were 68, 71, 74, and 77 keV for small, medium, large, and extra-large (xlarge) phantoms, respectively; for maximum iodine CNR, the optimal energies were 66, 68, 70, 72 keV. With the optimal monochromatic energy, the noise level was similar to and the CNR was better than that in a single-energy scan at 120 kV for the same radiation dose. Compared to an 80 kV scan, however, the iodine CNR in monochromatic images was lower for the small, medium, and large phantoms. Conclusions: In dual-source dual-energy CT, optimal virtual monochromatic energy depends on patient size, dose partitioning, and the image quality metric optimized. With the optimal monochromatic energy, the noise level was similar to and the iodine CNR was better than that in 120 kV images for the same radiation dose. Compared to single-energy 80 kV images, the iodine CNR in virtual monochromatic images was lower for small to large phantom sizes.

Yu Lifeng; Christner, Jodie A.; Leng Shuai; Wang Jia; Fletcher, Joel G.; McCollough, Cynthia H. [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)

2011-12-15T23:59:59.000Z

282

Low dose radiation interations with the transformation growth factor (TGF)-beta pathway  

E-Print Network (OSTI)

A major limiting factor for long-term, deep-space missions is the radiation dose to astronauts. Because the dose to the astronauts is a mixed field of low- and high-LET radiation, there is a need to understand the effects of both radiation types on whole tissue; however, there are limited published data on the effects of high-LET (linearenergy- transfer) radiation on tissue. Thus, we designed a perfusion chamber system for rat trachea in order to mimic in vivo respiratory tissue. We successfully maintained the perfused tracheal tissue ex vivo in a healthy and viable condition for up to three days. In addition, this project studied the effects of high-LET Fe particles on the overall transformation growth factor (TGF)-beta response after TGF-beta inactivation and compared the results to the TGF-beta response post x-ray irradiation. It was found that a TGF-beta response could be measured in the perfused tracheal tissue, for x-ray and Fe particle irradiations, despite the high autofluorescent background intrinsic to tissue. However, after comparing the TGF-beta response of x-ray irradiation to High-Z-Highenergy (HZE) irradiation, there was not a significant difference in radiation types. The TGF-beta response in x-ray and HZE irradiated perfusion chambers was also measured over time post irradiation. It was found that for 6 hour and 8 hour post irradiation, the TGF-beta response was higher for lower doses of radiation than for higher doses. This is in contrast to the 0 hour fixation which found the TGF-beta response to increase with increased dose. The inverse relationship found for 6 hour and 8 hour fixation times may indicate a threshold response for TGF-beta response; i.e., for low doses, a threshold of dose must be reached for an immediate TGF-beta response, otherwise the tissue responds more slowly to the irradiation damage. This result was unexpected and will require further investigation to determine if the threshold can be determined for the 250 kVp x-rays and 1 Gev Fe particles.

Maslowski, Amy Jesse

2007-08-01T23:59:59.000Z

283

Assessment of the Effective Dose Equivalent for External Photon Radiation: Volume 2: Calculational Techniques for Estimating Externa l Effective Dose Equivalent from Dosimeter Readings  

Science Conference Proceedings (OSTI)

Recent revisions to the radiation protection standards contained in Title 10 Part 20 of the Code of Federal Regulations require nuclear power plants to assess a worker's "effective dose equivalent" (EDE). This report explains the concept of effective dose equivalent and describes research to improve the dosimetric methods presently used for assessing EDE.

1995-09-28T23:59:59.000Z

284

Radiation-Induced Rib Fractures After Hypofractionated Stereotactic Body Radiation Therapy: Risk Factors and Dose-Volume Relationship  

SciTech Connect

Purpose: The purpose of this study was to clarify the incidence, the clinical risk factors, and the dose-volume relationship of radiation-induced rib fracture (RIRF) after hypofractionated stereotactic body radiation therapy (SBRT). Methods and Materials: One hundred sixteen patients treated with SBRT for primary or metastatic lung cancer at our institution, with at least 6 months of follow-up and no previous overlapping radiation exposure, were included in this study. To determine the clinical risk factors associated with RIRF, correlations between the incidence of RIRF and the variables, including age, sex, diagnosis, gross tumor volume diameter, rib-tumor distance, and use of steroid administration, were analyzed. Dose-volume histogram analysis was also conducted. Regarding the maximum dose, V10, V20, V30, and V40 of the rib, and the incidences of RIRF were compared between the two groups divided by the cutoff value determined by the receiver operating characteristic curves. Results: One hundred sixteen patients and 374 ribs met the inclusion criteria. Among the 116 patients, 28 patients (46 ribs) experienced RIRF. The estimated incidence of rib fracture was 37.7% at 3 years. Limited distance from the rib to the tumor (<2.0 cm) was the only significant risk factor for RIRF (p = 0.0001). Among the dosimetric parameters used for receiver operating characteristic analysis, the maximum dose showed the highest area under the curve. The 3-year estimated risk of RIRF and the determined cutoff value were 45.8% vs. 1.4% (maximum dose, {>=}42.4 Gy or less), 51.6% vs. 2.0% (V40, {>=}0.29 cm{sup 3} or less), 45.8% vs. 2.2% (V30, {>=}1.35 cm{sup 3} or less), 42.0% vs. 8.5% (V20, {>=}3.62 cm{sup 3} or less), or 25.9% vs. 10.5% (V10, {>=}5.03 cm{sup 3} or less). Conclusions: The incidence of RIRF after hypofractionated SBRT is relatively high. The maximum dose and high-dose volume are strongly correlated with RIRF.

Asai, Kaori [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Shioyama, Yoshiyuki, E-mail: shioyama@radiol.med.kyushu-u.ac.jp [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Nakamura, Katsumasa; Sasaki, Tomonari; Ohga, Saiji; Nonoshita, Takeshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Yoshitake, Tadamasa [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Heavy Particle Therapy and Radiation Oncology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Ohnishi, Kayoko [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan)] [Department of Radiology, National Center for Global Health and Medicine, Tokyo (Japan); Terashima, Kotaro; Matsumoto, Keiji [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Hirata, Hideki [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan); Honda, Hiroshi [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)] [Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka (Japan)

2012-11-01T23:59:59.000Z

285

Internal absorber solar collector  

DOE Patents (OSTI)

Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

Sletten, Carlyle J. (106 Nagog Hill Rd., Acton, MA 01720); Herskovitz, Sheldon B. (88 Hammond St., Acton, MA 01720); Holt, F. S. (46 Emerson Rd., Winchester, MA 01890); Sletten, E. J. (Chestnut Hill Rd. R.F.D. Rte. #4, Amherst, NH 03031)

1981-01-01T23:59:59.000Z

286

QUANTITY OF RADIATION REACHING GONADAL AREAS DURING THERAPY. IV. FACTORS INFLUENCING OVARY DOSE  

SciTech Connect

Attempts were made to evaluate the circumstances influencing the quantity of radiation reaching the ovaries during dermatologic radiation therapy, and to devise effective methods for reducing the amount to well within acceptable limits. Measurements were made in a specially constructed, life-size, pressed- wood (masonite) phantom which could be used in almost any position that might be assumed by man during routine x-ray therapy, and with provisions for insertion of an ionization chamber at the anatomic site representing an ovary. The various parameters which might influence ovary dose during conventional dermatologic x- ray procedures that were studied included: x-ray quality (kvp), tube current (ma), beam collimation and field size, shielding, angle of the beam in relation to the ovaries, and proximity of treatment site to the ovaries. Ovarian dose was measured during irradiation of the face, upper chest, and back, using each of the parameters alone and then in various combinations. The results, presented in tables and graphs, show that in order to minimize ovary dose during dermatologic x-ray therapy, one should utilize lower tube kilovoltage, softer radiation, appropriate collimation, effective shielding (minimizing area of field irraiated) with no added filtration, increased distance between the x-ray beam axis and the ovaries, and angling on the x-ray tube away from the ovaries. The gonad dose can best be reduced by exerting all of these simple and inexpensive means every time dermatologic radiation is administered. However, from these measurements it was evident that of the body areas studied, some may be irradiated without fear of exceeding even the max permissible dose to the ovaries, whereas other areas cannot be treated with x-rays without overdosing the ovaries regardless of the pre cautions taken. (BBB)

Witten, V.H.; Lee, H.

1963-05-01T23:59:59.000Z

287

Comparative Study of Different {beta}-Radiation Doses for Preventing Pterygium Recurrence  

SciTech Connect

Purpose: To compare the pterygium recurrence rates after treatment with two different {beta}-radiation doses. Methods and Materials: A total of 84 patients with a mean age of 63.0 {+-} 10.3 years (men, 48 eyes, and women, 47 eyes) and initially treated with {beta}-radiation after pterygium excision were recruited. The mean follow-up period was 49.9 {+-} 51.3 months. The patients were assigned to two dose groups: a high-dose (40 Gy) or a low-dose (20 Gy) group. The statistical significance of differences in patient age, pterygium size, and interval between surgery and radiotherapy were analyzed in the 20-Gy group using the Cox proportional hazard model at p < .05. Results: The high- and low-dose groups included 28 and 67 eyes, respectively. Pterygia recurred in 11 eyes, all in the low-dose group. The interval between surgery and radiotherapy was not a significant predictor of recurrence. Smaller pterygia had a lower risk of recurrence than pterygia that had encroached the pupillary area (pterygium located within one-third of the corneal radius from the limbus, corrected hazard ratio [HR], 0.069; 95% confidence interval [CI], 0.006-0.766; p = .030; pterygium extending beyond one-third of the corneal radius, corrected HR, 0.188; 95% CI, 0.018-0.696; p = 0.019; and pterygium reaching the pupillary area, corrected HR, 0.184; 95% CI, 0.036-0.929; p = .040). Older age was marginally significant as a negative predictor of recurrence (HR, 0.943; 95% CI, 0.887-1.003; p = .061). No scleromalacia developed during the follow-up period. Conclusions: {beta}-Radiation at 40 Gy was more efficacious than at 20 Gy in preventing pterygium recurrence without scleromalacia development, particularly for large-size pterygia and those in young patients.

Yamada, Takayuki, E-mail: tyamada-oph@umin.ac.jp [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Mochizuki, Hideki [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Ue, Takahiro [Department of Ophthalmology, Hiroshima Red Cross and Atomic Bomb Survivors Hospital, Hiroshima (Japan); Kiuchi, Yoshiaki [Department of Ophthalmology and Visual Science, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima (Japan); Takahashi, Yasuhiro [Department of Ophthalmology and Visual Science, Aichi Medical University School of Medicine, Aichi (Japan); Oinaka, Matsuyoshi [Department of Ophthalmology, Hiroshima Red Cross and Atomic Bomb Survivors Hospital, Hiroshima (Japan)

2011-12-01T23:59:59.000Z

288

Metabolomic Response of Human Skin Tissue to Low Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

Understanding how human organs respond to ionizing radiation (IR) at a systems biology level and identifying biomarkers for IR exposure at low doses can help provide a scientific basis for establishing radiation protection standards. Little is known regarding the physiological responses to low dose IR at the metabolite level, which represents the end-point of biochemical processes inside cells. Using a full thickness human skin tissue model and GC-MS-based metabolomics analysis, we examined the metabolic perturbations at three time points (3, 24 and 48 hr) after exposure to 3, 10 and 200 cGy of X-rays. PLS-DA score plots revealed dose- and time-dependent clustering between sham and irradiated groups. Importantly, a comparable number of metabolites were detected to have significant change 48 hr after exposure to 3 and 10 cGy of irradiation, when compared with the high dose of 200 cGy. Biochemical pathway analysis showed perturbations to DNA/RNA damage and repair, lipid and energy metabolisms, even at low doses of IR.

Hu, Zeping; Kim, Young-Mo; Sowa, Marianne B.; Robinson, Robert J.; Gao, Xiaoli; Metz, Thomas O.; Morgan, William F.; Zhang, Qibin

2012-05-18T23:59:59.000Z

289

Mitochondrial-Derived Oxidants and Cellular Responses to Low Dose/Low LET Ionizing Radiation  

SciTech Connect

Exposure to ionizing radiation results in the immediate formation of free radicals and other reactive oxygen species (ROS). It has been assumed that the subsequent injury processes leading to genomic instability and carcinogenesis following radiation, derive from the initial oxidative damage caused by these free radicals and ROS. It is now becoming increasingly obvious that metabolic oxidation/reduction (redox) reactions can be altered by irradiation leading to persistent increases in steady-state levels of intracellular free radicals and ROS that contribute to the long term biological effects of radiation exposure by causing chronic oxidative stress. The objective during the last period of support (DE-FG02-05ER64050; 5/15/05-12/31/09) was to determine the involvement of mitochondrial genetic defects in metabolic oxidative stress and the biological effects of low dose/low LET radiation. Aim 1 was to determine if cells with mutations in succinate dehydrogenase (SDH) subunits C and D (SDHC and SDHD in mitochondrial complex II) demonstrated increases in steady-state levels of reactive oxygen species (ROS; O2- and H2O2) as well as demonstrating increased sensitivity to low dose/low LET radiation (10 cGy) in cultured mammalian cells. Aim #2 was to determine if mitochondrially-derived ROS contributed to increased sensitivity to low dose/low LET radiation in mammalian cells containing mutations in SDH subunits. Aim #3 was to determine if a causal relationship existed between increases in mitochondrial ROS production, alterations in electron transport chain proteins, and genomic instability in the progeny of irradiated cells. Evidence gathered in the 2005-2009 period of support demonstrated that mutations in genes coding for mitochondrial electron transport chain proteins (ETC); either Succinate Dehydrogenase (SDH) subunit C (SDHC) or subunit D (SDHD); caused increased ROS production, increased genomic instability, and increased sensitivity to low dose/low LET radiation that could be mitigated by over expression of the H2O2 metabolizing enzyme, catalase, and/or the mitochondrial form of superoxide dismutase (MnSOD). Furthermore, using radiation-induced genomically unstable cells, it was shown that steady-state levels of H2O2 were significantly elevated for many cell generations following exposure, catalase suppressed the radiation-induced mutator phenotype when added long after radiation exposure, unstable clones showed evidence of mitochondrial dysfunction some of which was characterized by improper assembly of SDH subunits (particularly subunit B), and chemical inhibitors of SDH activity could decrease steady-state levels of H2O2 as well as mutation frequency. These results support the hypotheses that 1) SDH mutations could contribute to transformation by inducing genomic instability and a mutator phenotype via increasing steady-state levels of ROS; 2) metabolic sources of O2- and H2O2 play a significant role in low dose radiation induced injury and genomic instability; and 3) increased mutation rates in irradiated mammal cells can be suppressed by scavengers of H2O2 (particularly catalase) long after radiation exposure. Overall the results obtained during this period of support provide clear evidence in support of the hypothesis that abnormal oxidative metabolism in mitochondria that result in increases in steady-sate levels of H2O2 and other ROS are capable of significantly contributing to radiation-induced mutator phenotypes in mammalian cells.

Spitz, Douglas R.

2009-11-09T23:59:59.000Z

290

Nuclear Decay Data in the MIRD (Medical Internal Radiation Dose) Format  

DOE Data Explorer (OSTI)

MIRD is a database of evaluated nuclear decay data for over 2,100 radioactive nuclei. Data are extracted from ENSDF, processed by the program RadList, and used for medical internal radiation dose calculations. When using the MIRD interface, tables of nuclear and atomic radiations from nuclear decay and decay scheme drawings will be produced in the MIRD format from the Evaluated Nuclear Structure Data File (ENSDF) for the specified nuclide. Output may be either HTML-formatted tables and JPEG drawings, PostScript tables and drawings, or PDF tables and drawings.

291

Low Dose Radiation Research Program: Comparisons of IR and ROS for  

NLE Websites -- All DOE Office Websites (Extended Search)

Comparisons of IR and ROS for Induction of Damage to Cells Comparisons of IR and ROS for Induction of Damage to Cells Kathryn D. Held1, Yvonne L. McCarey1, Laurence Tartier1, Elena V. Rusyn1, Giuseppe Schettino2, Melvyn Folkard2, Kevin M. Prise2, and Barry D. Michael2 1Department of Radiation Oncology, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114; 2Gray Laboratory Cancer Research Trust, Mount Vernon Hospital, Northwood, HA6 2JR, UK Accurate evaluation of the risks associated with exposure to low doses of ionizing radiation (IR) is a major challenge for environmental sciences. Studies on the mechanisms of the actions of low doses of IR are needed to help understand possible risks. IR exerts its effects on cells through production of reactive oxidizing species (ROS) such as ·OH, H2O2 and

292

Low Dose Radiation Stimulates Antioxidant Capacity in the Brain and Lessens  

NLE Websites -- All DOE Office Websites (Extended Search)

Stimulates Antioxidant Capacity in the Brain and Lessens Stimulates Antioxidant Capacity in the Brain and Lessens Behavioral Symptoms in a 6-OHDA-Induced Rat Model of Parkinson's Disease Mohan Doss Fox Chase Cancer Center Abstract Background: Progressive degeneration of dopaminergic neurons in the substantia nigra (SN) pars compacta results in motor deficits in Parkinson’s disease (PD) patients. Oxidative damage to the nigral dopaminergic neurons has been implicated in the pathogenesis of Parkinson’s disease. Our hypothesis is that low dose radiation induces the production of antioxidants in the brain, which could provide protection to the dopaminergic neurons, potentially leading to prevention or stabilization of PD. The purpose of the study is (1) to determine the effect of low dose radiation on the total antioxidant capacity in SN in

293

Increased radiation dose at mammography due to prolonged exposure, delayed processing, and increased film darkening  

SciTech Connect

Four single-emulsion films introduced over the past 2 years--Du Pont Microvision, Fuji MiMa, Konica CM, and Eastman Kodak OM--were compared with Eastman Kodak OM SO-177 (Min-RE) film to evaluate their varying effects on mean glandular dose of reciprocity law failure due to prolonged exposure, delayed processing, and increased film darkening as a result of increased radiation exposure to improve penetration of glandular tissue. Exposures over 1.3 seconds led to increased radiation doses of 20%-30%. Delays in processing of 6 hours decreased processing speed by 11%-32% for all films except Du Pont Microvision. Optical density increases of 0.40 required 20%-30% more skin exposure for all five films. Optimal viewing densities were also evaluated and found to be different for each of the five films. Mammographers need to be aware of these differences in mammographic films to achieve maximum contrast at mammography.

Kimme-Smith, C.; Bassett, L.W.; Gold, R.H.; Chow, S. (UCLA Medical Center (USA))

1991-02-01T23:59:59.000Z

294

Low Dose Radiation Research Program: Regulation of NF-kB and MnSOD in Low  

NLE Websites -- All DOE Office Websites (Extended Search)

NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive NF-kB and MnSOD in Low Dose Radiation-Induced Adaptive Responses in Mouse and Human Skin Cells Jian Jian Li School of Health Sciences, Purdue University West Lafayette, Indiana Why this Project? To determine if low dose ionizing radiation-induced adaptive responses in skin cells are mediated by activation of signaling networks. Project Goals To evaluate the signaling networks involving transcription factor NF-kB and the mitochondrial antioxidant protein MnSOD. To determine if NF-kB is activated by low dose radiation in vivo. To determine if NF-kB activation is critical in the pathways that produce adaptive responses. Experimental Approach Cells transfected with NF-kB luciferase responder genes will be used to define a dose-response relationship for activation of the NF-kB gene. NF-kB

295

Dosimetric impact of Acuros XB deterministic radiation transport algorithm for heterogeneous dose calculation in lung cancer  

SciTech Connect

Purpose: The novel deterministic radiation transport algorithm, Acuros XB (AXB), has shown great potential for accurate heterogeneous dose calculation. However, the clinical impact between AXB and other currently used algorithms still needs to be elucidated for translation between these algorithms. The purpose of this study was to investigate the impact of AXB for heterogeneous dose calculation in lung cancer for intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT). Methods: The thorax phantom from the Radiological Physics Center (RPC) was used for this study. IMRT and VMAT plans were created for the phantom in the Eclipse 11.0 treatment planning system. Each plan was delivered to the phantom three times using a Varian Clinac iX linear accelerator to ensure reproducibility. Thermoluminescent dosimeters (TLDs) and Gafchromic EBT2 film were placed inside the phantom to measure delivered doses. The measurements were compared with dose calculations from AXB 11.0.21 and the anisotropic analytical algorithm (AAA) 11.0.21. Two dose reporting modes of AXB, dose-to-medium in medium (D{sub m,m}) and dose-to-water in medium (D{sub w,m}), were studied. Point doses, dose profiles, and gamma analysis were used to quantify the agreement between measurements and calculations from both AXB and AAA. The computation times for AAA and AXB were also evaluated. Results: For the RPC lung phantom, AAA and AXB dose predictions were found in good agreement to TLD and film measurements for both IMRT and VMAT plans. TLD dose predictions were within 0.4%-4.4% to AXB doses (both D{sub m,m} and D{sub w,m}); and within 2.5%-6.4% to AAA doses, respectively. For the film comparisons, the gamma indexes ({+-}3%/3 mm criteria) were 94%, 97%, and 98% for AAA, AXB{sub Dm,m}, and AXB{sub Dw,m}, respectively. The differences between AXB and AAA in dose-volume histogram mean doses were within 2% in the planning target volume, lung, heart, and within 5% in the spinal cord. However, differences up to 8% between AXB and AAA were found at lung/soft tissue interface regions for individual IMRT fields. AAA was found to be 5-6 times faster than AXB for IMRT, while AXB was 4-5 times faster than AAA for VMAT plan. Conclusions: AXB is satisfactorily accurate for the dose calculation in lung cancer for both IMRT and VMAT plans. The differences between AXB and AAA are generally small except in heterogeneous interface regions. AXB D{sub w,m} and D{sub m,m} calculations are similar inside the soft tissue and lung regions. AXB can benefit lung VMAT plans by both improving accuracy and reducing computation time.

Han Tao; Followill, David; Repchak, Roman; Molineu, Andrea; Howell, Rebecca; Salehpour, Mohammad [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Mikell, Justin [Department of Radiation Physics, the University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas 77030 (United States); Mourtada, Firas [Department of Radiation Physics, the University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Department of Radiation Oncology, Christiana Care Health System, Newark, Delaware 19713 (United States)

2013-05-15T23:59:59.000Z

296

A Low-Dose Ipsilateral Lung Restriction Improves 3-D Conformal Planning for Partial Breast Radiation Therapy  

Science Conference Proceedings (OSTI)

In trials of 3D conformal external beam partial breast radiotherapy (PBRT), the dosimetrist must balance the priorities of achieving high conformity to the target versus minimizing low-dose exposure to the normal structures. This study highlights the caveat that in the absence of a low-dose lung restriction, the use of relatively en-face fields may meet trial-defined requirements but expose the ipsilateral lung to unnecessary low-dose radiation. Adding a low-dose restriction that {dose resulted in successful plans in 88% of cases. This low-dose lung limit should be used in PBRT planning.

Mitchell, Tracy [Radiation Therapy Program, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, University of Victoria, Victoria, British Columbia (Canada); Truong, Pauline T., E-mail: ptruong@bccancer.bc.c [Radiation Therapy Program, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, University of Victoria, Victoria, British Columbia (Canada); Salter, Lee; Graham, Cathy; Gaffney, Helene; Beckham, Wayne; Olivotto, Ivo A. [Radiation Therapy Program, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, University of Victoria, Victoria, British Columbia (Canada)

2011-04-01T23:59:59.000Z

297

Image Quality and Radiation Dose Assessment of a Digital Mammography System  

Science Conference Proceedings (OSTI)

Image quality and radiation dose of a direct amorphous selenium digital mammography system were considered in terms of contrast to noise ratio (CNR) and average glandular dose (AGD). They were measured for various qualities and breast phantom thicknesses with different types of breast tissue composition to determine optimal radiation quality and dose. Three sets of breast tissue equivalent slabs (30%:70%, 50%:50% and 70%:30% glandular-adipose) with thickness of 2 cm to 7 cm and 0.2 mm aluminum foil were used to provide certain CNR. Two different combinations of anode/ilter material and a wide range of tube voltages were employed for each phantom thickness. Phantom images with grid were acquired using automatic exposure control (AEC) mode for each thickness. Phantom images without grid were also obtained in manual exposure mode by selecting the same anode/filter combination and kVp as the image obtained with grid at the same thickness, but varying mAs of 10 to 200 mAs. Optimization indicated that relatively high energy beam qualities should be used with a greater dose to compensate for lower energy x-rays. The results also indicate that current AEC setting for a fixed detector is not optimal.

Isa, N. M.; Hassan, W. M. S. W. [Department of Physics, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Abdullah, W. A. K. W. [Department of Radiology, Hospital USM, 16150 Kubang Kerian, Kelantan (Malaysia); Othman, F. [Department of Diagnostic Imaging, Hospital Putrajaya, Pres, 62250 Putrajaya, Walayah Persekutuan (Malaysia); Ramli, A. A. M. [Malaysian Nuclear Agency, 43000 Kajang, Selangor (Malaysia)

2010-07-07T23:59:59.000Z

298

Low Dose Radiation Research Program: Multi-cellular Crosstalk in Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

About this Project About this Project Multi-cellular Crosstalk in Radiation Damage Technical Abstracts 2006 Workshop: Low-LET Bystander Effects in Cells In Vitro Are Significantly Less Than Published For High-LET Radiation Blakely, E.A., Thompson, A.C., Chang, P., Schwarz, R.I., Bjornstad, K., Rosen, C., Wisnewski, C., and Mocherla, D. 2005 Workshop: X-ray Microbeam Bystander Studies with Human Mammary Epithelial Cells and Fibroblasts Blakely, E.A., Schwarz, R.I., Thompson, A.C., Bjornstad, K.A., Chang, P.Y., Rosen, C.J., Sudar, D., Romano, R., and Parvin, B. 2003 Workshop: 12.5 keV X-ray Microbeam Bystander Studies with Human Mammary Epithelial Cells and Fibroblasts Blakely, E.A., Schwarz, R.I., Thompson, A.C., Bjornstad, K.A., Chang, P.Y., Rosen, C.J., and Sudar, D. 2001 Workshop:

299

High-dose MVCT image guidance for stereotactic body radiation therapy  

Science Conference Proceedings (OSTI)

Purpose: Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance. Methods: Two nonstandard, high-dose imaging modes were created on a tomotherapy machine by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison. Results: MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp/mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable. Conclusions: High-dose imaging modes are made possible on a clinical tomotherapy machine by increasing the LINAC pulse rate. Increasing the imaging dose results in increased CNRs; making it easier to distinguish the boundaries of low contrast objects. The imaging dose levels observed in this work are considered acceptable at our institution for SBRT treatments delivered in 3-5 fractions.

Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D.; Chao, Edward; Lucas, Dan; Flynn, Ryan T.; Miften, Moyed [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States); Accuray Inc., Madison, Wisconsin 53717 (United States); Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242 (United States); Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado 80045 (United States)

2012-08-15T23:59:59.000Z

300

Radiation dose assessment methodology and preliminary dose estimates to support US Department of Energy radiation control criteria for regulated treatment and disposal of hazardous wastes and materials  

Science Conference Proceedings (OSTI)

This report provides unit dose to concentration levels that may be used to develop control criteria for radionuclide activity in hazardous waste; if implemented, these criteria would be developed to provide an adequate level of public and worker health protection, for wastes regulated under U.S, Environmental Protection Agency (EPA) requirements (as derived from the Resource Conservation and Recovery Act [RCRA] and/or the Toxic Substances Control Act [TSCA]). Thus, DOE and the US Nuclear Regulatory Commission can fulfill their obligation to protect the public from radiation by ensuring that such wastes are appropriately managed, while simultaneously reducing the current level of dual regulation. In terms of health protection, dual regulation of very small quantities of radionuclides provides no benefit.

Aaberg, R.L.; Baker, D.A.; Rhoads, K.; Jarvis, M.F.; Kennedy, W.E. Jr.

1995-07-01T23:59:59.000Z

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301

Low Dose Ionizing Radiation and HZE Particle Effects on Adult Hippocampal  

NLE Websites -- All DOE Office Websites (Extended Search)

and HZE Particle Effects on Adult Hippocampal and HZE Particle Effects on Adult Hippocampal Neurogenesis and mRNA Expression Kerry O'Banion University of Rochester School of Medicine & Dentistry Abstract Most of our knowledge about low dose radiation effects relates to DNA damage and chromosomal aberrations that result in cell death or alterations in genetic programs leading to malignancy. In addition To direct DNA damage, there is accumulating evidence that radiation induced alterations in the microenvironment can have significant effects on programs of cell replication and differentiation such as neurogenesis in adult mammalian brain. Adult neurogenesis in the hippocampus is postulated to play an important role in learning and memory and manipulations that alter neurogenesis, including inhibition following radiation exposure, have been

302

Mechanisms underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

underlying cellular responses of cells from haemopoeitic underlying cellular responses of cells from haemopoeitic tissue to low dose-low LET radiation Munira Kadhim 1 , Sarah Irons 1 , Deborah Bowler 1 , Virginia Serra 1 , Stefania Militi 2 , Kim Chapman 1 1 Genomic Instability Research Group, School of Life Sciences, Oxford Brookes University, Gipsy Lane, Headington, Oxford, Oxfordshire, OX3 0BP, UK 2 Mammalian Genetics Unit, Medical Research Council Harwell, Harwell Science and Innovation Campus, Oxfordshire, OX11 0RD, UK Radiation-induced responses at the cellular and whole body levels are influenced by genetic predisposition, with implications for environmental and potentially, diagnostic exposures. Currently, the extent to which genetic background play a role in the mechanisms and signalling pathways involved in radiation-induced

303

Low Dose Radiation Research Program: DNA Damage in Acutely Irradiated F2  

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DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal DNA Damage in Acutely Irradiated F2 Mice with a History of Paternal F0 Germline Irradiation Authors: J.E. Baulch and O.G. Raabe Institutions: Center for Health and the Environment, University of California, Davis, CA. The main goal of this grant is to evaluate heritable, transgenerational effects of low dose, low-linear-energy-transfer (LET) radiation (0.1 Gy attenuated 137Cs gamma rays) on Type B spermatogonia in 129SVE mice; wild-type and heterozygous for Ataxia-telangiectasia (AT). The ATM heterozygotes are carriers for a genetic mutation (AT mutated, ATM) that is thought to predispose both humans and mice to radiation sensitivity. Experiments conducted in our laboratory have demonstrated heritable effects of paternal germline exposure to ionizing radiation in mice using 1.0 Gy of

304

Technology Assessment and Roadmap for the Emergency Radiation Dose Assessment Program  

SciTech Connect

A Joint Interagency Working Group (JIWG) under the auspices of the Department of Homeland Security Office of Research and Development conducted a technology assessment of emergency radiological dose assessment capabilities as part of the overall need for rapid emergency medical response in the event of a radiological terrorist event in the United States. The goal of the evaluation is to identify gaps and recommend general research and development needs to better prepare the Country for mitigating the effects of such an event. Given the capabilities and roles for responding to a radiological event extend across many agencies, a consensus of gaps and suggested development plans was a major goal of this evaluation and road-mapping effort. The working group consisted of experts representing the Departments of Homeland Security, Health and Human Services (Centers for Disease Control and the National Institutes of Health), Food and Drug Administration, Department of Defense and the Department of Energy's National Laboratories (see appendix A for participants). The specific goals of this Technology Assessment and Roadmap were to: (1) Describe the general context for deployment of emergency radiation dose assessment tools following terrorist use of a radiological or nuclear device; (2) Assess current and emerging dose assessment technologies; and (3) Put forward a consensus high-level technology roadmap for interagency research and development in this area. This report provides a summary of the consensus of needs, gaps and recommendations for a research program in the area of radiation dosimetry for early response, followed by a summary of the technologies available and on the near-term horizon. We then present a roadmap for a research program to bring present and emerging near-term technologies to bear on the gaps in radiation dose assessment and triage. Finally we present detailed supporting discussion on the nature of the threats we considered, the status of technology today, promising emerging technologies and references for further reading.

Turteltaub, K W; Hartman-Siantar, C; Easterly, C; Blakely, W

2005-10-03T23:59:59.000Z

305

A multi-sensor approach for assessing the impacts of ultraviolet-absorbing aerosols on top of atmosphere radiative fluxes  

Science Conference Proceedings (OSTI)

One year (June 2006-May 2007) of the Clouds and the Earth's Radiant Energy System (CERES) top of atmosphere (TOA) shortwave (SW) and longwave (LW) fluxes are used with Ozone Monitoring Instrument-Aerosol Index (OMI-AI) data to assess the direct radiative ...

Thomas A. Jones; Sundar A. Christopher

2011-08-01T23:59:59.000Z

306

Worker radiation doses in the United States at the dawn of the atomic era (1940--1960)  

SciTech Connect

Radiation doses to workers at the Manhattan Engineer District (MED) and US Atomic Energy Commission (AEC) sites due to external irradiation during 1940--1960 are reviewed. Categorized radiation dose data were available from AEC annual reports for some years. Annual individual radiation dose data for ten MED/AEC sites for all years were available from the US Department of Energy`s (DOE) Comprehensive Epidemiologic Data Resource (CEDR). These data are combined to produce an estimate of external collective dose equivalent to 172,000 person-rems (1720 person-Sv) for 1940--1960. During this period there were 41 overexposures, 19 criticality incidents, and 3 deaths due to acute radiation syndrome among several hundred thousand workers.

Strom, D.J.; Smith, M.H.; Swinth, K.L. [Pacific Northwest Lab., Richland, WA (United States); Pettengill, H.J. [Westinghouse Hanford Co., Richland, WA (United States)

1994-06-01T23:59:59.000Z

307

Chloroquine Improves Survival and Hematopoietic Recovery After Lethal Low-Dose-Rate Radiation  

SciTech Connect

Purpose: We have previously shown that the antimalarial agent chloroquine can abrogate the lethal cellular effects of low-dose-rate (LDR) radiation in vitro, most likely by activating the ataxia-telangiectasia mutated (ATM) protein. Here, we demonstrate that chloroquine treatment also protects against lethal doses of LDR radiation in vivo. Methods and Materials: C57BL/6 mice were irradiated with a total of 12.8 Gy delivered at 9.4 cGy/hour. ATM null mice from the same background were used to determine the influence of ATM. Chloroquine was administered by two intraperitoneal injections of 59.4 {mu}g per 17 g of body weight, 24 hours and 4 hours before irradiation. Bone marrow cells isolated from tibia, fibula, and vertebral bones were transplanted into lethally irradiated CD45 congenic recipient mice by retroorbital injection. Chimerism was assessed by flow cytometry. In vitro methylcellulose colony-forming assay of whole bone marrow cells and fluorescence activated cell sorting analysis of lineage depleted cells were used to assess the effect of chloroquine on progenitor cells. Results: Mice pretreated with chloroquine before radiation exhibited a significantly higher survival rate than did mice treated with radiation alone (80% vs. 31%, p = 0.0026). Chloroquine administration before radiation did not affect the survival of ATM null mice (p = 0.86). Chloroquine also had a significant effect on the early engraftment of bone marrow cells from the irradiated donor mice 6 weeks after transplantation (4.2% vs. 0.4%, p = 0.015). Conclusion: Chloroquine administration before radiation had a significant effect on the survival of normal but not ATM null mice, strongly suggesting that the in vivo effect, like the in vitro effect, is also ATM dependent. Chloroquine improved the early engraftment of bone marrow cells from LDR-irradiated mice, presumably by protecting the progenitor cells from radiation injury. Chloroquine thus could serve as a very useful drug for protection against the harmful effects of LDR radiation.

Lim Yiting [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Hedayati, Mohammad; Merchant, Akil A.; Zhang Yonggang; Yu, Hsiang-Hsuan M. [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Kastan, Michael B. [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States) [Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee (United States); Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina (United States); Matsui, William, E-mail: matsuwi@jhmi.edu [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)] [Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); DeWeese, Theodore L., E-mail: deweete@jhmi.edu [Department of Radiation Oncology and Molecular Radiation Sciences, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States)

2012-11-01T23:59:59.000Z

308

Radiation Therapy With Full-Dose Gemcitabine and Oxaliplatin for Unresectable Pancreatic Cancer  

Science Conference Proceedings (OSTI)

Purpose: We completed a Phase I trial of gemcitabine and oxaliplatin with concurrent radiotherapy in patients with previously untreated pancreatic cancer. The results of a subset of patients with unresectable disease who went on to receive planned additional therapy are reported here. Methods and Materials: All patients received two 28-day cycles of gemcitabine (1,000 mg/m{sup 2} on Days 1, 8, and 15) and oxaliplatin (40-85 mg/m{sup 2} on Days 1 and 15, per a dose-escalation schema). Radiation therapy was delivered concurrently with Cycle 1 (27 Gy in 1.8-Gy fractions). At 9 weeks, patients were reassessed for resectability. Those deemed to have unresectable disease were offered a second round of treatment consisting of 2 cycles of gemcitabine and oxaliplatin and 27 Gy of radiation therapy (total, 54 Gy). Radiation was delivered to the gross tumor volume plus 1 cm by use of a three-dimensional conformal technique. We used the Common Terminology Criteria for Adverse Events to assess acute toxicity. Late toxicity was scored per the Radiation Therapy Oncology Group scale. Computed tomography scans were reviewed to determine pattern of failure, local response, and disease progression. Kaplan-Meier methodology and Cox regression models were used to evaluate survival and freedom from failure. Results: Thirty-two patients from the Phase I dose-escalation study had unresectable disease, three of whom had low-volume metastatic disease. Of this group, 16 patients went on to receive additional therapy to complete a total of 4 cycles of chemotherapy and 54 Gy of concurrent radiation. For this subset, 38% had at least a partial tumor response at a median of 3.2 months. Median survival was 11.8 months (range, 4.4-26.3 months). The 1-year freedom from local progression rate was 93.8% (95% confidence interval, 63.2-99.1). Conclusions: Radiation therapy to 54 Gy with concurrent full-dose gemcitabine and oxaliplatin is well tolerated and results in favorable rates of local tumor response and 1-year freedom from local progression.

Hunter, Klaudia U.; Feng, Felix Y. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Griffith, Kent A. [Comprehensive Cancer Center Biostatistics Unit, University of Michigan, Ann Arbor, MI (United States); Francis, Isaac R. [Department of Radiology, University of Michigan, Ann Arbor, MI (United States); Lawrence, Theodore S. [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States); Desai, Sameer [Department of Internal Medicine, University of Michigan, Ann Arbor, MI (United States); Murphy, James D. [School of Medicine, University of Michigan, Ann Arbor, MI (United States); Zalupski, Mark M. [Department of Internal Medicine, University of Michigan, Ann Arbor, MI (United States); Ben-Josef, Edgar, E-mail: edgarb@med.umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, MI (United States)

2012-07-01T23:59:59.000Z

309

MOLECULAR MECHANISM OF SUPPRESSION OF NEOPLASTIC TRANSFORMATION BY LOW DOSES OF LOW LET RADIATION  

Science Conference Proceedings (OSTI)

We are currently funded (9/01-8/04) by the DOE Low Dose Radiation Research Program to examine mechanisms underlying the suppression of neoplastic transformation in vitro by low doses of low LET radiation. For the new studies proposed under Notice 04-21, we intend to follow up on our observation that upregulation of DNA repair may be an important factor and that its importance is dose-dependent. The experimental system will be the human hybrid cell neoplastic transformation assay that we are currently using. We propose to test the following hypothesis: Down-regulation of DNA dsb repair will abrogate the low dose suppression of neoplastic transformation. Using the technique of RNA silencing, it is proposed to test the effect of down-regulation of the two major DNA dsb repair pathways, homologous recombination (HR) and non-homologous end-joining (NHEJ), on the dose response relationship for neoplastic transformation. Based on prior studies, we predict that this will result in abrogation of the suppressive effect at doses in the range 1 to 10 cGy, but not at lower doses. The proposed experiments will also help address the question as to which of the two DNA repair pathways may be the most important in causing suppression of transformation. HR is a pathway that is predominant in S and G2 phase cells and is known to be less error-prone than the NHEJ pathway that is predominant in G1 phase. We hypothesize that down-regulation of HR will result in the most effective abrogation of suppression. An important component of this study will be the determination of the how abrogation of DNA dsb repair impacts the spontaneous transformation frequency, presumably a consequence of endogeneous DNA damage. Experiments will be carried out using partially synchronized populations of cells enriched for G1 and S/G2 respectively. In addition to the endpoint of neoplastic transformation the impact of down-regulation of HR and NHEJ on the formation and disappearance of the DNA dsb marker, gamma-H2AX, will be studied.

J.LESIE REDPATH, PH.D.

2011-03-29T23:59:59.000Z

310

INDOS: conversational computer codes to implement ICRP-10-10A models for estimation of internal radiation dose to man  

SciTech Connect

INDOS1, INDOS2, and INDOS3 (the INDOS codes) are conversational FORTRAN IV programs, implemented for use in time-sharing mode on the ORNL PDP-10 System. These codes use ICRP10-10A models to estimate the radiation dose to an organ of the body of Reference Man resulting from the ingestion or inhalation of any one of various radionuclides. Two patterns of intake are simulated: intakes at discrete times and continuous intake at a constant rate. The IND0S codes provide tabular output of dose rate and dose vs time, graphical output of dose vs time, and punched-card output of organ burden and dose vs time. The models of internal dose calculation are discussed and instructions for the use of the INDOS codes are provided. The INDOS codes are available from the Radiation Shielding Information Center, Oak Ridge National Laboratory, P. O. Box X, Oak Ridge, Tennessee 37830. (auth)

Killough, G.G.; Rohwer, P.S.

1974-03-01T23:59:59.000Z

311

Low Dose Radiation Research Program: A Variable Energy Soft X-ray  

NLE Websites -- All DOE Office Websites (Extended Search)

Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of Variable Energy Soft X-ray Microprobe to Investigate Mechanisms of the Radiation Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kevin M Prise and Barry D Michael. Institutions: Gray Cancer Institute. We are currently engaged on two projects in the Low-dose Program: "Low dose studies with focused X-rays in cell and tissue models: mechanisms of bystander and genomic instability responses" (DE-FG07-99ER62877) and "Mechanistic modeling of bystander effects: An integrated theoretical and experimental approach" (DE-FG02-02ER63305). Central to both of these studies is a unique micro irradiation facility that uses ultrasoft X-rays focused to a sub micron beam for individual cell and sub cellular targeting. This facility allows us to selectively irradiate individual

312

Hysterosalpingography using a flat panel unit: Evaluation and optimization of ovarian radiation dose  

Science Conference Proceedings (OSTI)

Purpose: The aim of the present study was the evaluation and optimization of radiation dose to the ovaries (D) in hysterosalpingography (HSG). Methods: The study included a phantom study and a clinical one. In the phantom study, we evaluated imaging results for different geometrical setups and irradiation conditions. In the clinical study, 34 women were assigned into three different fluoroscopy modes and D was estimated with direct cervical TLD measurements. Results: In the phantom study, we used a source-to-image-distance (SID) of 110 cm and a field diagonal of 48 cm, and thus decreased air KERMA rate (KR) by 19% and 70%, respectively, for beam filtration: 4 mm Al and 0.9 mm Cu (Low dose). The least radiation exposure was accomplished by using the 3.75 pps fluoroscopy mode in conjunction with beam filtration: Low dose. In the clinical study, D normalized to 50 s of fluoroscopy time with a 3.75 pps fluoroscopy mode reached a value of 0.45 {+-} 0.04 mGy. Observers' evaluation of diagnostic image quality did not significantly differ for the three different modes of acquisition that were compared. Conclusions: Digital spot radiographs could be omitted in modern flat panel systems during HSG. Fluoroscopy image acquisitions in a modern flat panel unit at 3.75 pps and a beam filtration of 4 mm Al and 0.9 mm Cu demonstrate acceptable image quality with an average D equal to 0.45 mGy. This value is lower compared to the studied literature. For these reasons, the proposed method may be recommended for routine HSG examination in order to limit radiation exposure to the ovaries.

Messaris, Gerasimos A. T.; Abatzis, Ilias; Kagadis, George C.; Samartzis, Alexandros P.; Athanasopoulou, Panagiota; Christeas, Nikolaos; Katsanos, Konstantinos; Karnabatidis, Dimitrios; Nikiforidis, George C. [Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion, Greece and Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, 'EVANGELISMOS' General Hospital, 45-47 Ypsilantou Street, GR 106 76 Athens (Greece); Philips Hellas, 44 Kifisias Avenue, GR 151 25 Marousi (Greece); Department of Radiology, School of Medicine, University of Patras, GR 265 04 Rion (Greece); Department of Medical Physics, University Hospital of Patras, GR 265 04 Rion, Greece and Department of Medical Physics, School of Medicine, University of Patras, GR 265 04 Rion (Greece)

2012-07-15T23:59:59.000Z

313

Low Dose Radiation Research Program: A Variable-Energy Soft X-Ray  

NLE Websites -- All DOE Office Websites (Extended Search)

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation-Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kirk Atkinson, Kevin M Prise, Barry D Michael Institutions: Gray Cancer Institute, PO BO Box100, Mount Vernon Hospital, Northwood, HA6 2JR, UK The Gray Cancer Institute (GCI) has pioneered the use of X-ray focussing techniques to develop systems for micro-irradiating individual cells and sub-cellular targets. Our prototype X-ray microprobe was developed alongside our existing charged-particle microbeam to address problems specific to low LET radiations, or where very precise targeting accuracy and dose delivery are required. This facility was optimised for focusing 278 eV CK X-rays; however there are a number of reasons for extending the

314

Low Dose Radiation Research Program: A Paracrine Signal Mediates The Cell  

NLE Websites -- All DOE Office Websites (Extended Search)

A Paracrine Signal Mediates The Cell Transformation Response To Low A Paracrine Signal Mediates The Cell Transformation Response To Low Dose Gamma Radiation in JB6 Cells. Authors: Thomas J. Weber,1 Robert W. Siegel,2 Lye M. Markillie,1 William B. Chrisler,1 Xingye C. Lei,3 and Nancy H. Colburn4 Institutions: 1Cell Biology and Biochemistry, Pacific Northwest National Laboratory, Richland, Washington. 2Protein Function, Pacific Northwest National Laboratory, Richland, Washington. 3Statistical and Mathematical Sciences, Pacific Northwest National Laboratory, Richland, Washington. 4Gene Regulation Section, Laboratory of Cancer Prevention, National Cancer Institute at Frederick, Frederick, Maryland. The carcinogenic response to radiation is complex and may involve adaptive cellular responses as well as a bystander effect mediated by paracrine or

315

8-1 2001 SITE ENVIRONMENTAL REPORT CHAPTER 8: RADIOLOGICAL DOSE ASSESSMENT  

E-Print Network (OSTI)

8-1 2001 SITE ENVIRONMENTAL REPORT CHAPTER 8: RADIOLOGICAL DOSE ASSESSMENT During 2001: RADIOLOGICAL DOSE ASSESSMENT 011-400 013-400 017-400 030-400 037-400 038-450 049-400 054-400 066-400073-400 074- tional to the absorbed dose of radiation. The environmental TLDs at BNL are composed of calcium fluoride

Homes, Christopher C.

316

Fundamentals of Radiation Dosimetry  

Science Conference Proceedings (OSTI)

The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

Bos, Adrie J. J. [Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629JB Delft (Netherlands)

2011-05-05T23:59:59.000Z

317

Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation  

Science Conference Proceedings (OSTI)

We investigated the low dose dependency of the transcriptional response of human cells to characterize the shape and biological functions associated with the dose response curve and to identify common and conserved functions of low dose expressed genes across cells and tissues. Human lymphoblastoid (HL) cells from two unrelated individuals were exposed to graded doses of radiation spanning the range of 1-10 cGy were analyzed by transcriptome profiling, qPCR and bioinformatics, in comparison to sham irradiated samples. A set of {approx}80 genes showed consistent responses in both cell lines; these genes were associated with homeostasis mechanisms (e.g., membrane signaling, molecule transport), subcellular locations (e.g., Golgi, and endoplasmic reticulum), and involved diverse signal transduction pathways. The majority of radiation-modulated genes had plateau-like responses across 1-10 cGy, some with suggestive evidence that transcription was modulated at doses below 1 cGy. MYC, FOS and TP53 were the major network nodes of the low-dose response in HL cells. Comparison our low dose expression findings in HL cells with those of prior studies in mouse brain after whole body exposure, in human keratinocyte cultures, and in endothelial cells cultures, indicates that certain components of the low dose radiation response are broadly conserved across cell types and tissues, independent of proliferation status.

Wyrobek, A. J.; Manohar, C. F.; Nelson, D. O.; Furtado, M. R.; Bhattacharya, M. S.; Marchetti, F.; Coleman, M.A.

2011-04-18T23:59:59.000Z

318

Brachial Plexus-Associated Neuropathy After High-Dose Radiation Therapy for Head-and-Neck Cancer  

SciTech Connect

Purpose: To identify clinical and treatment-related predictors of brachial plexus-associated neuropathies after radiation therapy for head-and-neck cancer. Methods and Materials: Three hundred thirty patients who had previously completed radiation therapy for head-and-neck cancer were prospectively screened using a standardized instrument for symptoms of neuropathy thought to be related to brachial plexus injury. All patients were disease-free at the time of screening. The median time from completion of radiation therapy was 56 months (range, 6-135 months). One-hundred fifty-five patients (47%) were treated by definitive radiation therapy, and 175 (53%) were treated postoperatively. Radiation doses ranged from 50 to 74 Gy (median, 66 Gy). Intensity-modulated radiation therapy was used in 62% of cases, and 133 patients (40%) received concurrent chemotherapy. Results: Forty patients (12%) reported neuropathic symptoms, with the most common being ipsilateral pain (50%), numbness/tingling (40%), motor weakness, and/or muscle atrophy (25%). When patients with <5 years of follow-up were excluded, the rate of positive symptoms increased to 22%. On univariate analysis, the following factors were significantly associated with brachial plexus symptoms: prior neck dissection (p = 0.01), concurrent chemotherapy (p = 0.01), and radiation maximum dose (p < 0.001). Cox regression analysis confirmed that both neck dissection (p < 0.001) and radiation maximum dose (p < 0.001) were independently predictive of symptoms. Conclusion: The incidence of brachial plexus-associated neuropathies after radiation therapy for head-and-neck cancer may be underreported. In view of the dose-response relationship identified, limiting radiation dose to the brachial plexus should be considered when possible.

Chen, Allen M., E-mail: allen.chen@ucdmc.ucdavis.edu [Department of Radiation Oncology, University of California, Davis School of Medicine, Sacramento, California (United States); Hall, William H. [Department of Radiation Oncology, University of California, Davis School of Medicine, Sacramento, California (United States)] [Department of Radiation Oncology, University of California, Davis School of Medicine, Sacramento, California (United States); Li, Judy; Beckett, Laurel [Department of Biostatistics, University of California, Davis School of Medicine, Sacramento, California (United States)] [Department of Biostatistics, University of California, Davis School of Medicine, Sacramento, California (United States); Farwell, D. Gregory [Department of Otolaryngology-Head and Neck Surgery, University of California, Davis School of Medicine, Sacramento, California (United States)] [Department of Otolaryngology-Head and Neck Surgery, University of California, Davis School of Medicine, Sacramento, California (United States); Lau, Derick H. [Department of Medical Oncology, University of California, Davis School of Medicine, Sacramento, California (United States)] [Department of Medical Oncology, University of California, Davis School of Medicine, Sacramento, California (United States); Purdy, James A. [Department of Radiation Oncology, University of California, Davis School of Medicine, Sacramento, California (United States)] [Department of Radiation Oncology, University of California, Davis School of Medicine, Sacramento, California (United States)

2012-09-01T23:59:59.000Z

319

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation.  

NLE Websites -- All DOE Office Websites (Extended Search)

Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Whole Genome Analysis of Functional Protein Binding Sites and DNA Methylation: Application to p53 and Low Dose Ionizing Radiation. Krassimira Botcheva, John J. Dunn and Carl W. Anderson Biology Department, Brookhaven National Laboratory, Upton, NY 11973, USA The effects of exposure to low doses of ionizing radiation on humans results largely from changes in gene expression mediated by the activation of sequence-specific DNA binding proteins (transcription factors) as well as changes to other chromosomal proteins and perhaps to DNA. To develop a molecular understanding of the consequences of exposures to low doses of ionizing radiation, it will be necessary to understanding where radiation-activated transcription factors bind in whole genomes and how

320

Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E.  

NLE Websites -- All DOE Office Websites (Extended Search)

Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Prevention of Low Dose Radiation-Induced Genomic Instability with Clinically Relevant Non-Protein Thiols and Vitamin E. J.S. Murley 1 , Y. Kataoka 1 , W.F. Morgan 2 , and D.J. Grdina 1 . The University of Chicago, Chicago, IL 1 , The University of Maryland Medical School, Baltimore, MD 2 Induced or delayed radioprotection is a novel phenomenon that shares many similarities with the low dose radiation-induced radiobiological phenomenon referred to as the adaptive response. Induced or delayed radioprotection is defined as an enhancement in the radiation resistance of cells at long times following their exposure to non-protein thiols (NPT) such as WR1065, the free thiol form of amifostine. This effect is the result of the induction of a cascade of intracellular

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321

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary  

NLE Websites -- All DOE Office Websites (Extended Search)

low-dose, low-LET γ-radiation and BaP injection on pulmonary low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott Lovelace Respiratory Research Institute Abstract Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance function (Liu, 2007; Bogdandi et al., 2010). One measure of activated immune cell function is their expression of markers on their cell surface that are

322

Individual Radiation Exposure Dose Due to Support Activities at Safe Shelters in Fukushima Prefecture  

E-Print Network (OSTI)

Immediately after the accidents in the nuclear power stations in Fukushima on March 11, the Japanese Government ordered the evacuation of the residents within a 20-km radius from the station on March 12, and asked various institutions to monitor the contamination levels of the residents. Hirosaki University, which is located 355 km north of Fukushima City, decided to send support staff to Fukushima. This report summarizes the results of the exposure of 13 individual teams from March 15 to June 20. The support teams surveyed more than 5,000 people during this period. Almost all subjects had external contamination levels of less than 13 kcpm on Geiger-Mller (GM) survey meter, which is categorized as no contamination level. The 1 st team showed the highest external exposure dose, but the 4 th team onward showed no significant change. Subsequently, the internal radiation exposure was measured using a whole body counter that indicated undetectable levels in all staff members. Although the measured external radiation exposure dose cannot have serious biological effects on the health of an individual, a follow-up study of the residents in Fukushima and other regions where

Satoru Monzen; Masahiro Hosoda; Shinji Tokonami; Minoru Osanai; Hironori Yoshino; Mitsuaki A. Yoshida; Masatoshi Yamada; Yasushi Asari; Kei Satoh; Ikuo Kashiwakura

2011-01-01T23:59:59.000Z

323

An optimized colony forming assay for low-dose-radiation cell survival measurement  

Science Conference Proceedings (OSTI)

The aim of this study is to develop a simple and reliable method to quantify the cell survival of low-dose irradiations. Two crucial factors were considered, the same number of cells plated in each flask and an appropriate interval between cell plating and irradiation. For the former, we optimized cell harvest with trypsin, diluted cells in one container, and directly seeded cells on the bottom of flasks in a low density before irradiation. Reproducible plating efficiency was obtained. For the latter, we plated cells on the bottom of flasks and then monitored the processing of attachment, cell cycle variations, and the plating efficiency after exposure to 20 cGy of X-rays. The results showed that a period of 4.5 h to 7.5 h after plating was suitable for further treatment. In order to confirm the reliability and feasibility of our method, we also measured the survival curves of these M059K and M059J glioma cell lines by following the optimized protocol and obtained consistent results reported by others with cell sorting system. In conclusion, we successfully developed a reliable and simple way to measure the survival fractions of human cells exposed to low dose irradiation, which might be helpful for the studies on low-dose radiation biology.

Zhu J.; Sutherland B.; Hu W.; Ding N.; Ye C.; Usikalu M.; Li S.; Hu B.; Zhou G.

2011-11-01T23:59:59.000Z

324

Gamma Radiation Dose Rate in Air due to Terrestrial Radionuclides in Southern Brazil: Synthesis by Geological Units and Lithotypes Covered by the Serra do Mar Sul Aero?Geophysical Project  

Science Conference Proceedings (OSTI)

The absorbed dose rates in air due to terrestrial radionuclides were estimated from aerial gamma spectrometric data for an area of 48

Rodrigo O. Bastos; Carlos R. Appoloni; Jos P. P. Pinese

2008-01-01T23:59:59.000Z

325

Risk of Low Dose/Low Dose Rate Ionizing Radiation to Humans Symposium at the EMS 2009 Annual Meeting - September 2006  

Science Conference Proceedings (OSTI)

The low dose symposium thoughtfully addressed controversy of risk from low dose radiation exposure, hormesis and radon therapy. The stem cell symposium cogently considered the role of DNA damage and repair in hematopoietic stem cells underlying aging and malignancy and provocatively presented evidence that stem cells may have distinct morphologies and replicative properties, as well as special roles in cancer initiation. In the epigenetics symposium, studies illustrated the long range interaction of epigenetic mechanisms, the roles of CTCF and BORIS in region/specific regulation of epigenetic processes, the impact of DNA damage on epigenetic processes as well as links between epigenetic mechanisms and early nutrition and bystander effects.

Morgan, William F.; von Borstel, Robert C.; Brenner,; Redpath, J. Leslie; Erickson, Barbra E.; Brooks,

2009-11-12T23:59:59.000Z

326

Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Low Dose Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Modular Systems Biology applied to TGFbeta and DNA Damage Response Signaling following Low Dose Radiation Francis A. Cucinotta 1 , Yongfeng Li 2 , Minli Wang 2 , Claudio Carra 2 , Janice Pluth 3 , and Peter O'Neill 4 1 NASA Johnson Space Center, Houston, TX 2 U.S.R.A. Division of Life Sciences, Houston TX 3 Lawrence Berkeley National Laboratory, Berkeley CA 4 Oxford University, Oxford UK Abstract: Modular systems biology (MSB) describes the complexity of biological systems using well defined modules that represent distinct biological response pathways or sub-systems within pathways. We review mathematical concepts from control theory that can be used to identify and construct well defined modules for describing complex biological processes. The DNA damage response and TGFbeta/Smad signaling are two important response pathways following

327

Relationship of five anthropometric measurements at age 18 to radiation dose among atomic bomb survivors exposed in utero  

SciTech Connect

Five body measurements-standing height, body weight, sitting height, chest circumference and intercristal diameter-of 18-year-old atomic bomb survivors exposed in utero in Hiroshima and Nagasaki were analyzed in relation to DS86 uterine dose. Age in utero was divided into four periods: 0-7, 8-15, 16-25 and [>=]26 weeks. This categorization is based upon the study of radiation-induced brain damage. The linear regression analyses for these five variables showed significant decreases with increasing dose. The regression coefficients were -2.65 cm/Gy for standing height, -2.46 kg/Gy for body weight, -0.92 cm/Gy for sitting height, -1.37 cm/Gy for chest circumference and -0.32 cm/Gy for intercristal diameter. The multivariate test statistic for the overall dose effect on five body measurements was significant, but the interaction between dose and gestational period was not significant. Principal-component analysis was applied to the five variables. For the first-component scores, the dose effect was significant, but the interaction between dose and gestational period was not significant. For the second-component scores, the dose effect was significant specifically at 0.7 weeks. The radiation dose effect on the second principal component found at 0-7 weeks of gestation suggests that malformation occur in this period. 17 refs., 2 figs., 4 tabs.

Nakashima, Eiji (Radiation Effects Research Foundation, Minami-ku (Japan))

1994-04-01T23:59:59.000Z

328

New mammography screen/film combinations: Imaging characteristics and radiation dose  

Science Conference Proceedings (OSTI)

Five types of film (Kodak OM, Kodak OM-SO177, Konica CM, Dupont Microvision, and Fuji MiMa) exposed in combination with seven different intensifying screens (Min R, Min R Medium, Siemens Orthox MA, Kyokka HR Mammo Fine, Agfa Gevaert Detail S (old and new), and Konica Monarch) were processed for either 90 sec (at 33.3{degrees}C) or 3 min (at 35.0 degrees C). The films imaged a Computerized Imaging Reference System phantom with additional detail test objects placed on its surface to produce four groups of objects with which to evaluate resolution and contrast. For objects that tested resolution, the Kyokka HR Mammo Fine (Fuji) screen was statistically significantly superior; for objects that tested contrast, the Konica Monarch screen was statistically significantly superior. Extended processing did not affect Dupont and Kodak OM film as much as it affected the other films. It did affect contrast for the other films tested. The mean glandular doses from gridless exposures ranged from 32 to 80 mrad (0.32-0.80 mGy) over all film/screen/processing combinations for a 4.5-cm-thick test object. Several new film/screen combinations can provide images superior to the Kodak Min R/OM combination at a reduced radiation dose. The Kyokka HR Mammo Fine (Fuji) screen was found statistically superior in radiographic resolution of mammographic test objects and the Konica Monarch screen was found to be superior in defining contrast.

Kimme-Smith, C.; Bassett, L.W.; Gold, R.H.; Zheutlin, J.; Gornbein, J.A. (Iris Cantor Center for Breast Imaging, CA (USA))

1990-04-01T23:59:59.000Z

329

System and method for radiation dose calculation within sub-volumes of a monte carlo based particle transport grid  

DOE Patents (OSTI)

A system and method is disclosed for radiation dose calculation within sub-volumes of a particle transport grid. In a first step of the method voxel volumes enclosing a first portion of the target mass are received. A second step in the method defines dosel volumes which enclose a second portion of the target mass and overlap the first portion. A third step in the method calculates common volumes between the dosel volumes and the voxel volumes. A fourth step in the method identifies locations in the target mass of energy deposits. And, a fifth step in the method calculates radiation doses received by the target mass within the dosel volumes. A common volume calculation module inputs voxel volumes enclosing a first portion of the target mass, inputs voxel mass densities corresponding to a density of the target mass within each of the voxel volumes, defines dosel volumes which enclose a second portion of the target mass and overlap the first portion, and calculates common volumes between the dosel volumes and the voxel volumes. A dosel mass module, multiplies the common volumes by corresponding voxel mass densities to obtain incremental dosel masses, and adds the incremental dosel masses corresponding to the dosel volumes to obtain dosel masses. A radiation transport module identifies locations in the target mass of energy deposits. And, a dose calculation module, coupled to the common volume calculation module and the radiation transport module, for calculating radiation doses received by the target mass within the dosel volumes.

Bergstrom, Paul M. (Livermore, CA); Daly, Thomas P. (Livermore, CA); Moses, Edward I. (Livermore, CA); Patterson, Jr., Ralph W. (Livermore, CA); Schach von Wittenau, Alexis E. (Livermore, CA); Garrett, Dewey N. (Livermore, CA); House, Ronald K. (Tracy, CA); Hartmann-Siantar, Christine L. (Livermore, CA); Cox, Lawrence J. (Los Alamos, NM); Fujino, Donald H. (San Leandro, CA)

2000-01-01T23:59:59.000Z

330

Incorporating Heterogeneity Correction and 4DCT in Lung Stereotactic Body Radiation Therapy (SBRT): The Effect on Target Coverage, Organ-At-Risk Doses, and Dose Conformity  

SciTech Connect

This study evaluates the dosimetric impact of 4-dimensional computed tomography (4DCT) target volumes and heterogeneity correction (HC) on target coverage, organ-at-risk (OAR) doses, and dose conformity in lung stereotactic body radiation therapy (SBRT). Twelve patients with lung cancer, scanned using both helical CT and 4DCT, were treated with SBRT (60 Gy in 3 fractions). The clinical plans were calculated without HC and based on targets from the free-breathing helical CT scan (PTV{sub HEL}). Retrospectively, the clinical plans were recalculated with HC and were evaluated based on targets from 4DCT datasets (PTV{sub 4D}) accounting for patient-specific target motion. The PTV{sub 4D} was greater than PTV{sub HEL} when tumor motion exceeded 7.5 mm (vector). There were significant decreases in target coverage (V100) for the recalculated vs. clinical plans (0.84 vs. 0.94, p < 0.02) for the same monitor units. When the recalculated plans were optimized for equivalent V100 of the clinical plans, there were significant increases in the 60-Gy dose spillage (1.27 vs. 1.13, p < 0.001) and 30-Gy dose spillage (5.20 vs. 3.73, p < 0.001) vs. the clinical plans. There was a significant increase (p < 0.04) in the mean OAR doses between the optimized re-calculated and the clinical plan. Tumor motion is an important consideration for target volumes defined using helical CT. Lower prescription doses may be required when prospectively planning with HC to achieve a similar level of toxicity and dose spillage as expected when planning based on homogeneous dose calculations.

Franks, Kevin N. [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada); Purdie, Thomas G. [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada)], E-mail: Tom.Purdie@rmp.uhn.on.ca; Dawson, Laura A.; Bezjak, Andrea [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Jaffray, David A. [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada); Department of Medical Biophysics, University of Toronto, Toronto, Ontario (Canada); Bissonnette, Jean-Pierre [Radiation Medicine Program, Princess Margaret Hospital, Toronto, Ontario (Canada); Department of Radiation Oncology, University of Toronto, Toronto, Ontario (Canada)

2010-07-01T23:59:59.000Z

331

Genome Wide Evaluation of Normal Human Tissue in Response to Controlled, In vivo Low-Dose Low LET Ionizing Radiation Exposure: Pathways and Mechanisms Final Report, September 2013  

SciTech Connect

During course of this project, we have worked in several areas relevant to low-dose ionizing radiation. Using gene expression to measure biological response, we have examined the response of human skin exposed in-vivo to radation, human skin exposed ex-vivo to radiation, and a human-skin model exposed to radiation. We have learned a great deal about the biological response of human skin to low-dose ionizing radiation.

Rocke, David M. [University of California Davis

2013-09-09T23:59:59.000Z

332

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

M3-19 M3-19 3 Equations and Models for Calculating Dose to Biota and Deriving BCGs Based on the potential pathways of exposure, BCGs were derived for surface water, sediment, and soil. Calculated using conservative assumptions, the BCGs are intended to preclude the relevant biota from being exposed to radiation levels in excess of established or recommended biota dose limits. Determination of compliance with the dose limits requires that all organism- relevant environmental media be evaluated at the same time. This is done by using the "sum of fractions" approach commonly used in evaluating radionuclide discharges to the environment. 3.1 An Important Note on Estimating Internal Tissue Concentrations for Use in Dose Equations: The Lumped Parameter For most radionuclides, the single most important predictor of biota dose is the method used to estimate internal tissue concentrations.

333

Low dose radiation and cancer in A-bomb survivors: latency and non-linear dose-response in the 195090 mortality cohort  

E-Print Network (OSTI)

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Analyses of Japanese A-bomb survivors ' cancer mortality risks are used to establish recommended annual dose limits, currently set at 1 mSv (public) and 20 mSv (occupational). Do radiation doses below 20 mSv have significant impact on cancer mortality in Japanese A-bomb survivors, and is the dose-response linear? Methods: I analyse stomach, liver, lung, colon, uterus, and all-solid cancer mortality in the 0 20 mSv colon dose subcohort of the 195090 (grouped) mortality cohort, by Poisson regression using a time-lagged colon dose to detect latency, while controlling for gender, attained age, and age-atexposure. I compare linear and non-linear models, including one adapted from the cellular bystander effect for ? particles. Results: With a lagged linear model, Excess Relative Risk (ERR) for the liver and all-solid cancers is significantly positive and several orders of magnitude above extrapolations from the Life Span Study Report 12 analysis of the full cohort. Non-linear models are strongly superior to the linear model for the stomach (latency 11.89 years), liver (36.90), lung (13.60) and all-solid (43.86) in fitting

Greg Dropkin; Greg Dropkin

2007-01-01T23:59:59.000Z

334

Induction of nuclear factor kB after low-dose ionizing radiation involves a reactive oxygen intermediate signaling pathway  

Science Conference Proceedings (OSTI)

Reactive oxygen intermediates (ROIs) have been found to be the messengers in the activation of the kB transcription regulator in mitogen- or cytokine-stimulated cells, operating in conjunction with or independently of various other mechanisms; these include Ca{sup ++}-dependent and PKC-dependent cytoplasmic signaling pathways. We have recently reported that low-dose ionizing radiation induces NF-kB in human lymphoblastoid 244B cells. Since ionizing radiation generates free radicals in cells, we have investigated whether the ROIs generated by ionizing radiation induce NF-kB activity, and also whether they do so by a similar mechanism as in cells treated with PMA or H{sub 2}O{sub 2}. The results not only confirm a previous observation from our laboratory that low-dose ionizing radiation (0.1-2.0 Gy) activates kB transcription factor transiently with a maximal induction at 0.5 Gy exposure, but also demonstrate mechanistically that the activation of NF-kB by low-dose ionizing radiation can be inhibited considerably by the antioxidant N-acetyl-L-cysteine, indicating that at least the major part of the activation process is mediated by ROIs. These findings support the idea that ROIs can regulate the kB elements which in turn can serve as response elements for oxidant stress. 37 refs., 4 figs., 1 tab.

Mohan, N.; Meltz, M.L. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

1994-10-01T23:59:59.000Z

335

Lack of Radiation Dose or Quality Dependence of Epithelial-to-Mesenchymal Transition (EMT) Mediated by Transforming Growth Factor {beta}  

SciTech Connect

Purpose: Epithelial-to-mesenchymal transition (EMT) is a phenotype that alters cell morphology, disrupts morphogenesis, and increases motility. Our prior studies have shown that the progeny of human mammary epithelial cells (HMECs) irradiated with 2 Gy undergoes transforming growth factor {beta} (TGF-{beta})-mediated EMT. In this study we determined whether radiation dose or quality affected TGF-{beta}-mediated EMT. Methods and Materials: HMECs were cultured on tissue culture plastic or in Matrigel (BD Biosciences, San Jose, CA) and exposed to low or high linear energy transfer (LET) and TGF-{beta} (400 pg/mL). Image analysis was used to measure membrane-associated E-cadherin, a marker of functional epithelia, or fibronectin, a product of mesenchymal cells, as a function of radiation dose and quality. Results: E-cadherin was reduced in TGF-{beta}-treated cells irradiated with low-LET radiation doses between 0.03 and 2 Gy compared with untreated, unirradiated cells or TGF-{beta} treatment alone. The radiation quality dependence of TGF-{beta}-mediated EMT was determined by use of 1 GeV/amu (gigaelectron volt / atomic mass unit) {sup 56}Fe ion particles at the National Aeronautics and Space Administration's Space Radiation Laboratory. On the basis of the relative biological effectiveness of 2 for {sup 56}Fe ion particles' clonogenic survival, TGF-{beta}-treated HMECs were irradiated with equitoxic 1-Gy {sup 56}Fe ion or 2-Gy {sup 137}Cs radiation in monolayer. Furthermore, TGF-{beta}-treated HMECs irradiated with either high- or low-LET radiation exhibited similar loss of E-cadherin and gain of fibronectin and resulted in similar large, poorly organized colonies when embedded in Matrigel. Moreover, the progeny of HMECs exposed to different fluences of {sup 56}Fe ion underwent TGF-{beta}-mediated EMT even when only one-third of the cells were directly traversed by the particle. Conclusions: Thus TGF-{beta}-mediated EMT, like other non-targeted radiation effects, is neither radiation dose nor quality dependent at the doses examined.

Andarawewa, Kumari L.; Costes, Sylvain V. [Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Fernandez-Garcia, Ignacio [Department of Radiation Oncology, NYU Langone School of Medicine, New York, NY (United States); Chou, William S. [Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Department of Radiation Oncology, NYU Langone School of Medicine, New York, NY (United States); Ravani, Shraddha A.; Park, Howard [Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Barcellos-Hoff, Mary Helen, E-mail: mhbarcellos-hoff@nyumc.or [Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Department of Radiation Oncology, NYU Langone School of Medicine, New York, NY (United States)

2011-04-01T23:59:59.000Z

336

Internal Dose Estimates from  

E-Print Network (OSTI)

Appendix F Internal Dose Estimates from NTS Fallout F-1 #12;Radiation Dose to the Population...........................................................................................40 Comparison to dose estimates from global fallout

337

Raman spectroscopy of tumour cells exposed to clinically relevant doses of ionizing radiation.  

E-Print Network (OSTI)

??Improvements to radiation therapy treatment outcomes rely, in part, on consideration of patient specific radiosensitivity. Therefore an assay which quantifies radiation-induced biochemical changes, and subsequently (more)

Harder, Samantha

2013-01-01T23:59:59.000Z

338

The children of parents exposed to atomic bombs: Estimates of the genetic doubling dose of radiation for humans  

SciTech Connect

The data collected in Hiroshima and Nagasaki during the past 40 years on the children of survivors of the atomic bombings and on the children of a suitable control population are analyzed on the basis of the newly revised estimates of radiation doses. No statistically significant effects emerge with respect to eight different indicators. Since, however, it may confidently be assumed some mutations were induced, we have taken the data at face value and calculated the minimal gametic doubling doses of acute radiation for the individual indicators at various probability levels. An effort has also been made to calculate the most probable doubling dose for the indicators combined. The latter value is between 1.7 and 2.2 Sv. It is suggested the appropriate figure for chronic radiation would be between 3.4 and 4.5 Sv. These estimates suggest humans are less sensitive to the genetic effects of radiation than has been assumed on the basis of past extrapolations from experiments with mice.

Neel, J.V.; Schull, W.J.; Awa, A.A.; Satoh, C.; Kato, H.; Otake, M.; Yoshimoto, Y. (Univ. of Michigan Medical School, Ann Arbor (USA))

1990-06-01T23:59:59.000Z

339

Quantifying the Impact of Immediate Reconstruction in Postmastectomy Radiation: A Large, Dose-Volume Histogram-Based Analysis  

SciTech Connect

Purpose: To assess the impact of immediate breast reconstruction on postmastectomy radiation (PMRT) using dose-volume histogram (DVH) data. Methods and Materials: Two hundred forty-seven women underwent PMRT at our center, 196 with implant reconstruction and 51 without reconstruction. Patients with reconstruction were treated with tangential photons, and patients without reconstruction were treated with en-face electron fields and customized bolus. Twenty percent of patients received internal mammary node (IMN) treatment. The DVH data were compared between groups. Ipsilateral lung parameters included V20 (% volume receiving 20 Gy), V40 (% volume receiving 40 Gy), mean dose, and maximum dose. Heart parameters included V25 (% volume receiving 25 Gy), mean dose, and maximum dose. IMN coverage was assessed when applicable. Chest wall coverage was assessed in patients with reconstruction. Propensity-matched analysis adjusted for potential confounders of laterality and IMN treatment. Results: Reconstruction was associated with lower lung V20, mean dose, and maximum dose compared with no reconstruction (all P<.0001). These associations persisted on propensity-matched analysis (all P<.0001). Heart doses were similar between groups (P=NS). Ninety percent of patients with reconstruction had excellent chest wall coverage (D95 >98%). IMN coverage was superior in patients with reconstruction (D95 >92.0 vs 75.7%, P<.001). IMN treatment significantly increased lung and heart parameters in patients with reconstruction (all P<.05) but minimally affected those without reconstruction (all P>.05). Among IMN-treated patients, only lower lung V20 in those without reconstruction persisted (P=.022), and mean and maximum heart doses were higher than in patients without reconstruction (P=.006, P=.015, respectively). Conclusions: Implant reconstruction does not compromise the technical quality of PMRT when the IMNs are untreated. Treatment technique, not reconstruction, is the primary determinant of target coverage and normal tissue doses.

Ohri, Nisha [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Cordeiro, Peter G. [Department of Plastic Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Plastic Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Keam, Jennifer [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ballangrud, Ase [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Shi Weiji; Zhang Zhigang [Department of Biostatistics and Epidemiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Biostatistics and Epidemiology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Nerbun, Claire T.; Woch, Katherine M.; Stein, Nicholas F.; Zhou Ying [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); McCormick, Beryl; Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)] [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Ho, Alice Y., E-mail: HoA1234@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

2012-10-01T23:59:59.000Z

340

Characterization of the role of Fhit in maintenance of genomic integrity following low dose radiation, in vivo and in vitro  

Science Conference Proceedings (OSTI)

The major goal of this study is to determine the effects of the Fhit pathway on low dose (radiation (IR)-induced genetic instability. Reduction of Fhit protein expression is observed in most solid tumors particularly in those tumors resulting from exposure to environmental carcinogens. Therefore, characterization of the role of the Fhit-dependent pathway in preventing low dose IR-induced genetic instability will provide useful parameters for evaluating the low dose IR-induced risk of mutagenesis and carcinogenesis. We pursued 3 specific aims to study our hypothesis that the Fhit-dependent pathways maintain genomic integrity through adjusting checkpoint response and repair genes expression following low dose IR. Aim 1: Determine whether Fhit interaction with RPA is necessary for Fhit to affect the cellular response to low dose IR. We combined the approaches of in vitro (GST pull-down and site-directed mutagenesis) and in vivo (observing the co-localization and immunoprecipitation of Fhit and RPA in Fhit knock out mouse cells transfected with mutant Fhit which has lost ability to interact with RPA in vitro). Aim 2: Determine the role of genes whose expression is affected by Fhit in low dose irradiated cells. We analyzed the distinct signature of gene expression in low dose irradiated Fhit-/- cells compared with Fhit+/+ cells by combining microarray, gene transfection and siRNA approaches. Aim 3: Determine the role of Fhit in genetic susceptibility to low dose IR in vivo. We compared the gene mutation frequency and the fragile site stability in the cells isolated from the Fhit+/+ and Fhit-/- mice at 1.5 years following low dose IR. These results determine the role of the Fhit-dependent pathway in maintaining genomic integrity in vitro and in vivo, which provide a basis for choosing surrogate markers in the Fhit-dependent pathway to evaluate low dose IR-induced risk of mutagenesis and carcinogenesis.

Wang, Ya

2010-05-14T23:59:59.000Z

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341

Characterization of the role of Fhit in maintenance of genomic integrity following low dose radiation, in vivo and in vitro  

Science Conference Proceedings (OSTI)

The major goal of this study is to determine the effects of the Fhit pathway on low dose ({le} 0.1 Gy) ionizing radiation (IR)-induced genetic instability. Reduction of Fhit protein expression is observed in most solid tumors particularly in those tumors resulting from exposure to environmental carcinogens. Therefore, characterization of the role of the Fhit-dependent pathway in preventing low dose IR-induced genetic instability will provide useful parameters for evaluating the low dose IR-induced risk of mutagenesis and carcinogenesis. We pursued 3 specific aims to study our hypothesis that the Fhit-dependent pathways maintain genomic integrity through adjusting checkpoint response and repair genes expression following low dose IR. Aim 1: Determine whether Fhit interaction with RPA is necessary for Fhit to affect the cellular response to low dose IR. We combined the approaches of in vitro (GST pull-down and site-directed mutagenesis) and in vivo (observing the co-localization and immunoprecipitation of Fhit and RPA in Fhit knock out mouse cells transfected with mutant Fhit which has lost ability to interact with RPA in vitro). Aim 2: Determine the role of genes whose expression is affected by Fhit in low dose irradiated cells. We analyzed the distinct signature of gene expression in low dose irradiated Fhit-/- cells compared with Fhit+/+ cells by combining microarray, gene transfection and siRNA approaches. Aim 3: Determine the role of Fhit in genetic susceptibility to low dose IR in vivo. We compared the gene mutation frequency and the fragile site stability in the cells isolated from the Fhit+/+ and Fhit-/- mice at 1.5 years following low dose IR. These results determine the role of the Fhit-dependent pathway in maintaining genomic integrity in vitro and in vivo, which provide a basis for choosing surrogate markers in the Fhit-dependent pathway to evaluate low dose IR-induced risk of mutagenesis and carcinogenesis.

Ya Wang

2010-05-31T23:59:59.000Z

342

Do Intermediate Radiation Doses Contribute to Late Rectal Toxicity? An Analysis of Data From Radiation Therapy Oncology Group Protocol 94-06  

SciTech Connect

Purpose: To investigate whether the volumes of rectum exposed to intermediate doses, from 30 to 50 Gy, contribute to the risk of Grade {>=}2 late rectal toxicity among patients with prostate cancer receiving radiotherapy. Methods and Materials: Data from 1009 patients treated on Radiation Therapy Oncology Group protocol 94-06 were analyzed using three approaches. First, the contribution of intermediate doses to a previously published fit of the Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) model was determined. Next, the extent to which intermediate doses provide additional risk information, after taking the LKB model into account, was investigated. Third, the proportion of rectum receiving doses higher than a threshold, VDose, was computed for doses ranging from 5 to 85 Gy, and a multivariate Cox proportional hazards model was used to determine which of these parameters were significantly associated with time to Grade {>=}2 late rectal toxicity. Results: Doses <60 Gy had no detectable impact on the fit of the LKB model, as expected on the basis of the small estimate of the volume parameter (n = 0.077). Furthermore, there was no detectable difference in late rectal toxicity among cohorts with similar risk estimates from the LKB model but with different volumes of rectum exposed to intermediate doses. The multivariate Cox proportional hazards model selected V75 as the only value of VDose significantly associated with late rectal toxicity. Conclusions: There is no evidence from these data that intermediate doses influence the risk of Grade {>=}2 late rectal toxicity. Instead, the critical doses for this endpoint seem to be {>=}75 Gy. It is hypothesized that cases of Grade {>=}2 late rectal toxicity occurring among patients with V75 less than approximately 12% may be due to a 'background' level of risk, likely due mainly to biological factors.

Tucker, Susan L., E-mail: sltucker@mdanderson.org [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Dong, Lei [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Michalski, Jeff M. [Department of Radiation Oncology, Washington University, St. Louis, MO (United States)] [Department of Radiation Oncology, Washington University, St. Louis, MO (United States); Bosch, Walter R. [Department of Radiation Oncology, Washington University, St. Louis, MO (United States) [Department of Radiation Oncology, Washington University, St. Louis, MO (United States); Image-Guided Therapy QA Center, Washington University, St. Louis, MO (United States); Winter, Kathryn [American College of Radiology, Philadelphia, PA (United States)] [American College of Radiology, Philadelphia, PA (United States); Cox, James D. [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, TX (United States); Purdy, James A. [Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, CA (United States)] [Department of Radiation Oncology, University of California Davis Medical Center, Sacramento, CA (United States); Mohan, Radhe [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)] [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, TX (United States)

2012-10-01T23:59:59.000Z

343

Reduction of radiation dose to radiosensitive organs and its tradeoff with image quality in Computed Tomography  

E-Print Network (OSTI)

pilot study suggested a lot of opportunities to reduce radiationradiation dose in CT scan while maintaining image quality. The pilot

Zhang, Di

2012-01-01T23:59:59.000Z

344

About Radiation  

NLE Websites -- All DOE Office Websites (Extended Search)

Radiation What is radiation? Radiation is a form of energy that is a part of our everyday lives. All of us receive a "dose" of radiation each day. Most of the dose comes from...

345

Statistical issues in radiation dose-response analysis of employees of the nuclear industry in Oak Ridge, Tennessee  

Science Conference Proceedings (OSTI)

Poisson regression methods are used to describe dose-response relations for cancer mortality for a subcohort of 28,347 white male radiation workers. Age specific baseline rates are described using both internal and external (US white male) rates. Regression analyses are based on an analytic data structure (ADS) that consists of a table of observed deaths, expected deaths, and person-years at risk for each combination of levels of seven risk factors. The factors are socioeconomic status, length of employment, birth cohort, age at risk, facility, internal exposure, and external exposure. Each observation in the ADS consists of the index value of each of the stratifying factors, the observed deaths, the expected deaths, the person-years, and the ten year lagged average cumulative dose. Regression diagnostics show that a linear exponential relative risk model is not appropriate for these data. Results are presented using a main effects model for factors other than external radiation, and an excess relative risk term for cumulative external radiation dose.

Frome, E.L. [Oak Ridge National Lab., TN (United States); Watkins, J.P. [Oak Ridge Inst. for Science and Education, TN (United States). Center for Epidemiologic Research

1997-11-01T23:59:59.000Z

346

Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease  

SciTech Connect

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

2008-06-06T23:59:59.000Z

347

Early Brain Response to Low-Dose Radiation Exposure Involves Molecular Networks and Pathways Associated with Cognitive Functions, Advanced Aging and Alzheimer's Disease  

SciTech Connect

Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy, environmental nuclear contamination, as well as earth orbit and space missions. Analyses of transcriptome profiles of murine brain tissue after whole-body radiation showed that low-dose exposures (10 cGy) induced genes not affected by high dose (2 Gy), and low-dose genes were associated with unique pathways and functions. The low-dose response had two major components: pathways that are consistently seen across tissues, and pathways that were brain tissue specific. Low-dose genes clustered into a saturated network (p < 10{sup -53}) containing mostly down-regulated genes involving ion channels, long-term potentiation and depression, vascular damage, etc. We identified 9 neural signaling pathways that showed a high degree of concordance in their transcriptional response in mouse brain tissue after low-dose radiation, in the aging human brain (unirradiated), and in brain tissue from patients with Alzheimer's disease. Mice exposed to high-dose radiation did not show these effects and associations. Our findings indicate that the molecular response of the mouse brain within a few hours after low-dose irradiation involves the down-regulation of neural pathways associated with cognitive dysfunctions that are also down regulated in normal human aging and Alzheimer's disease.

Lowe, Xiu R; Bhattacharya, Sanchita; Marchetti, Francesco; Wyrobek, Andrew J.

2008-06-06T23:59:59.000Z

348

Activation of nuclear factor kB in human lymphoblastoid cells by low-dose ionizing radiation  

SciTech Connect

Nuclear factor kB (NF-kB) is a pleiotropic transcription factor which is involved in the transcriptional regulation of several specific genes. Recent reports demonstrated that ionizing radiation in the dose range of 2-50 Gy results in expression of NF-kB in human KG-1 myeloid leukemia cells and human B-lymphocyte precursor cells; the precise mechanism involved and the significance are not yet known. The present report demonstrates that even lower doses of ionizing radiation, 0.25-2.0 Gy, are capable of inducing expression of NF-kB in EBV-transformed 244B human lymphoblastoid cells. These results are in a dose range where the viability of the cells remains very high. After exposure to {sup 137}Cs {gamma} rays at a dose rate of 1.17 Gy/min, a maximum in expression of NF-kB was seen at 8 h after a 0.5-Gy exposure. Time-course studies revealed a biphasic time-dependent expression after 0.5-, 1- and 2-Gy exposures. However, for each time examined, the expression of NF-kB was maximum after the 0.5-Gy exposure. The expression of the p50 and p65 NF-kB subunits was also shown to be regulated differentially after exposures to 1.0 and 2.0 Gy. 32 refs., 3 figs.

Prasad, A.V.; Mohan, N.; Meltz, M.L.; Chandrasekar, B. [Univ. of Texas Health Science Center, San Antonio, TX (United States)

1994-06-01T23:59:59.000Z

349

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1 1 PRINCIPLES AND APPLICATION MODULE 1: PRINCIPLES AND APPLICATION DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M1-1 1 Introduction The U.S. Department of Energy (DOE) is accountable to Congress and the public for the safe conduct of its activities, including facility operation, waste management and disposal activities, and remediation of environmental contamination. These routine activities may result in releases of radionuclides to the air and water, accumulation of radionuclides in soil and sediment, and the potential for plants, animals, and members of the public to be exposed to radiation. DOE Order 5400.5, "Radiation Protection of the Public and the Environment" (1990a), lists the environmental radiation protection requirements that DOE and DOE- contractor employees must meet to protect aquatic animals. In addition, dose limits below

350

On the use of flux limiters in the discrete ordinates method for 3D radiation calculations in absorbing and scattering media  

Science Conference Proceedings (OSTI)

The application of flux limiters to the discrete ordinates method (DOM), S"N, for radiative transfer calculations is discussed and analyzed for 3D enclosures for cases in which the intensities are strongly coupled to each other such as: radiative equilibrium ... Keywords: Discrete ordinates method (DOM), Flux limiters, Newton-Krylov GMRES, Non-homogeneous 3D media, Radiation heat transfer, Radiative transfer equation (RTE), TVD schemes

William F. Godoy; Paul E. DesJardin

2010-05-01T23:59:59.000Z

351

Patient radiation doses in interventional cardiology in the U.S.: Advisory data sets and possible initial values for U.S. reference levels  

Science Conference Proceedings (OSTI)

Purpose: To determine patient radiation doses from interventional cardiology procedures in the U.S and to suggest possible initial values for U.S. benchmarks for patient radiation dose from selected interventional cardiology procedures [fluoroscopically guided diagnostic cardiac catheterization and percutaneous coronary intervention (PCI)]. Methods: Patient radiation dose metrics were derived from analysis of data from the 2008 to 2009 Nationwide Evaluation of X-ray Trends (NEXT) survey of cardiac catheterization. This analysis used deidentified data and did not require review by an IRB. Data from 171 facilities in 30 states were analyzed. The distributions (percentiles) of radiation dose metrics were determined for diagnostic cardiac catheterizations, PCI, and combined diagnostic and PCI procedures. Confidence intervals for these dose distributions were determined using bootstrap resampling. Results: Percentile distributions (advisory data sets) and possible preliminary U.S. reference levels (based on the 75th percentile of the dose distributions) are provided for cumulative air kerma at the reference point (K{sub a,r}), cumulative air kerma-area product (P{sub KA}), fluoroscopy time, and number of cine runs. Dose distributions are sufficiently detailed to permit dose audits as described in National Council on Radiation Protection and Measurements Report No. 168. Fluoroscopy times are consistent with those observed in European studies, but P{sub KA} is higher in the U.S. Conclusions: Sufficient data exist to suggest possible initial benchmarks for patient radiation dose for certain interventional cardiology procedures in the U.S. Our data suggest that patient radiation dose in these procedures is not optimized in U.S. practice.

Miller, Donald L.; Hilohi, C. Michael; Spelic, David C. [Center for Devices and Radiological Health, Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States)

2012-10-15T23:59:59.000Z

352

NFkB-mediated Prosurvival Network in Low Dose Radiation-induced...  

NLE Websites -- All DOE Office Websites (Extended Search)

approaches to improve normal tissue protection in caner radiation therapy. We found that ATM, a DNA damage sensor, is induced by LDR and responsible for activation of transcription...

353

Energy Absorbing Material  

To overcome limitations with cellular silicone foams, LLNL innovators have developed a new 3D energy absorbing material with tailored/engineered bulk-scale properties. The energy absorbing material has 3D patterned architectures specially designed for ...

354

Review of US and Japanese Methods to Reduce Personnel Dose and Control Radiation Fields  

Science Conference Proceedings (OSTI)

This report summarizes aspects of U.S. nuclear industry's performance in several areas related to radiation exposure management. The document supports efforts of the Japan Nuclear Energy Safety Organization (JNES) to find ways to reduce radiation exposure in Japanese plants.

2008-09-30T23:59:59.000Z

355

Estimation of Radiation Doses in the Marshall Islands Based on Whole Body Counting of Cesium-137 (137Cs) and Plutonium Urinalysis  

SciTech Connect

Under the auspices of the U.S. Department of Energy (USDOE), researchers from the Lawrence Livermore National Laboratory (LLNL) have recently implemented a series of initiatives to address long-term radiological surveillance needs at former nuclear test sites in the Republic of the Marshall Islands (RMI). The aim of this radiological surveillance monitoring program (RSMP) is to provide timely radiation protection for individuals in the Marshall Islands with respect to two of the most important internally deposited fallout radionuclides-cesium-137 ({sup 137}Cs) and long-lived isotopes 239 and 240 of plutonium ({sup 239+240}Pu) (Robison et al., 1997 and references therein). Therefore, whole-body counting for {sup 137}Cs and a sensitive bioassay for the presence of {sup 239+240}Pu excreted in urine were adopted as the two most applicable in vivo analytical methods to assess radiation doses for individuals in the RMI from internally deposited fallout radionuclides (see Hamilton et al., 2006a-c; Bell et al., 2002). Through 2005, the USDOE has established three permanent whole-body counting facilities in the Marshall Islands: the Enewetak Radiological Laboratory on Enewetak Atoll, the Utrok Whole-Body Counting Facility on Majuro Atoll, and the Rongelap Whole-Body Counting Facility on Rongelap Atoll. These whole-body counting facilities are operated and maintained by trained Marshallese technicians. Scientists from LLNL provide the technical support and training necessary for maintaining quality assurance for data acquisition and dose reporting. This technical basis document summarizes the methodologies used to calculate the annual total effective dose equivalent (TEDE; or dose for the calendar year of measurement) based on whole-body counting of internally deposited {sup 137}Cs and the measurement of {sup 239+240}Pu excreted in urine. Whole-body counting provides a direct measure of the total amount (or burden) of {sup 137}Cs present in the human body at the time of measurement. The amount of {sup 137}Cs detected is often reported in activity units of kilo-Becquerel (kBq), where 1 kBq equals 1000 Bq and 1 Bq = 1 nuclear transformation per second (t s{sup -1}). [However, in the United States the Curie (Ci) continues to be used as the unit of radioactivity; where 1 Ci = 3.7 x 10{sup 10} Bq.] The detection of {sup 239}Pu and {sup 240}Pu in bioassay (urine) samples indicates the presence of internally deposited (systemic) plutonium in the body. Urine samples that are collected in the Marshall Islands from volunteers participating in the RSMP are transported to LLNL, where measurements for {sup 239+240}Pu are performed using a state-of-the-art technology based on Accelerator Mass Spectrometry (AMS) (Hamilton et al., 2004, 2007; Brown et al., 2004). The urinary excretion of plutonium by RSMP volunteers is usually described in activity units, expressed as micro-Becquerel ({micro}Bq) of {sup 239+240}Pu (i.e., representing the sum of the {sup 239}Pu and {sup 240}Pu activity) excreted (lost) per day (d{sup -1}), where 1 {micro}Bq d{sup -1} = 10{sup -6} Bq d{sup -1} and 1 Bq = 1 t s{sup -1}. The systemic burden of plutonium is then estimated from biokinetic relationships as described by the International Commission on Radiological Protection (e.g., see ICRP, 1990). In general, nuclear transformations are accompanied by the emission of energy and/or particles in the form of gamma rays ({gamma}), beta particles ({beta}), and/or alpha particles ({alpha}). Tissues in the human body may adsorb these emissions, where there is a potential for any deposited energy to cause biological damage. The general term used to quantify the extent of any radiation exposure is referred to as the dose. The equivalent dose is defined by the average absorbed dose in an organ or tissue weighted by the average quality factor for the type and energy of the emission causing the dose. The effective dose equivalent (EDE; as applied to the whole body), is the sum of the average dose equivalent for each tissue weighted by each applicable tissue-specific weighing factor

Daniels, J; Hickman, D; Kehl, S; Hamilton, T

2007-06-11T23:59:59.000Z

356

Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 7  

SciTech Connect

The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in the continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This is volume 7 of the series. The abstracts in this bibliography were selected from proceedings of technical meetings and conferences, journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to radiation protection and dose reduction, and ranges from use of robotics to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 7 contains 293 abstract, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 7. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

Kaurin, D.G.; Khan, T.A.; Sullivan, S.G.; Baum, J.W. [Brookhaven National Lab., Upton, NY (United States)

1993-07-01T23:59:59.000Z

357

Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 8  

Science Conference Proceedings (OSTI)

The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in a continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This volume 8 of the series. The abstracts in this bibliography were selected form proceedings of technical meetings and conference journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to the many aspects of radiation protection and dose reduction, and ranges form use of robotics, to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 8 contains 232 abstracts, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 8. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

Sullivan, S.G.; Khan, T.A.; Xie, J.W. [Brookhaven National Lab., Upton, NY (United States)

1995-05-01T23:59:59.000Z

358

Non-Targeted Effects of Low Dose Ionizing Radiation Act Via TGFβ...  

NLE Websites -- All DOE Office Websites (Extended Search)

effect that mediates microenvironment composition. TGF is activated in mouse mammary gland following whole body exposure to doses of as low as 0.1 Gy and persists in the stroma...

359

Composition for absorbing hydrogen  

DOE Patents (OSTI)

A hydrogen absorbing composition is described. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

Heung, L.K.; Wicks, G.G.; Enz, G.L.

1995-05-02T23:59:59.000Z

360

Composition for absorbing hydrogen  

DOE Patents (OSTI)

A hydrogen absorbing composition. The composition comprises a porous glass matrix, made by a sol-gel process, having a hydrogen-absorbing material dispersed throughout the matrix. A sol, made from tetraethyl orthosilicate, is mixed with a hydrogen-absorbing material and solidified to form a porous glass matrix with the hydrogen-absorbing material dispersed uniformly throughout the matrix. The glass matrix has pores large enough to allow gases having hydrogen to pass through the matrix, yet small enough to hold the particles dispersed within the matrix so that the hydrogen-absorbing particles are not released during repeated hydrogen absorption/desorption cycles.

Heung, Leung K. (Aiken, SC); Wicks, George G. (Aiken, SC); Enz, Glenn L. (N. Augusta, SC)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
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361

Intensity Modulated Radiation Therapy Dose Painting for Localized Prostate Cancer Using {sup 11}C-choline Positron Emission Tomography Scans  

Science Conference Proceedings (OSTI)

Purpose: To demonstrate the technical feasibility of intensity modulated radiation therapy (IMRT) dose painting using {sup 11}C-choline positron emission tomography PET scans in patients with localized prostate cancer. Methods and Materials: This was an RT planning study of 8 patients with prostate cancer who had {sup 11}C-choline PET scans prior to radical prostatectomy. Two contours were semiautomatically generated on the basis of the PET scans for each patient: 60% and 70% of the maximum standardized uptake values (SUV{sub 60%} and SUV{sub 70%}). Three IMRT plans were generated for each patient: PLAN{sub 78}, which consisted of whole-prostate radiation therapy to 78 Gy; PLAN{sub 78-90}, which consisted of whole-prostate RT to 78 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy; and PLAN{sub 72-90}, which consisted of whole-prostate RT to 72 Gy, a boost to the SUV{sub 60%} to 84 Gy, and a further boost to the SUV{sub 70%} to 90 Gy. The feasibility of these plans was judged by their ability to reach prescription doses while adhering to published dose constraints. Tumor control probabilities based on PET scan-defined volumes (TCP{sub PET}) and on prostatectomy-defined volumes (TCP{sub path}), and rectal normal tissue complication probabilities (NTCP) were compared between the plans. Results: All plans for all patients reached prescription doses while adhering to dose constraints. TCP{sub PET} values for PLAN{sub 78}, PLAN{sub 78-90}, and PLAN{sub 72-90} were 65%, 97%, and 96%, respectively. TCP{sub path} values were 71%, 97%, and 89%, respectively. Both PLAN{sub 78-90} and PLAN{sub 72-90} had significantly higher TCP{sub PET} (P=.002 and .001) and TCP{sub path} (P<.001 and .014) values than PLAN{sub 78}. PLAN{sub 78-90} and PLAN{sub 72-90} were not significantly different in terms of TCP{sub PET} or TCP{sub path}. There were no significant differences in rectal NTCPs between the 3 plans. Conclusions: IMRT dose painting for localized prostate cancer using {sup 11}C-choline PET scans is technically feasible. Dose painting results in higher TCPs without higher NTCPs.

Chang, Joe H. [Radiation Oncology Centre, Austin Health, Victoria (Australia) [Radiation Oncology Centre, Austin Health, Victoria (Australia); University of Melbourne, Victoria (Australia); Lim Joon, Daryl [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Lee, Sze Ting [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Centre for PET, Austin Health, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Gong, Sylvia J. [Centre for PET, Austin Health, Victoria (Australia)] [Centre for PET, Austin Health, Victoria (Australia); Anderson, Nigel J. [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Scott, Andrew M. [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Centre for PET, Austin Health, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Davis, Ian D. [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Ludwig Institute for Cancer Research, Victoria (Australia); Clouston, David [Focus Pathology, Victoria (Australia)] [Focus Pathology, Victoria (Australia); Bolton, Damien [University of Melbourne, Victoria (Australia) [University of Melbourne, Victoria (Australia); Department of Urology, Austin Health, Victoria (Australia); Hamilton, Christopher S. [Radiation Oncology Centre, Austin Health, Victoria (Australia)] [Radiation Oncology Centre, Austin Health, Victoria (Australia); Khoo, Vincent, E-mail: vincent.khoo@rmh.nhs.uk [Radiation Oncology Centre, Austin Health, Victoria (Australia) [Radiation Oncology Centre, Austin Health, Victoria (Australia); University of Melbourne, Victoria (Australia); Department of Clinical Oncology, Royal Marsden Hospital and Institute of Cancer Research, London (United Kingdom)

2012-08-01T23:59:59.000Z

362

MILDOS - A Computer Program for Calculating Environmental Radiation Doses from Uranium Recovery Operations  

Science Conference Proceedings (OSTI)

The MILDOS Computer Code estimates impacts from radioactive emissions from uranium milling facilities. These impacts are presented as dose commitments to individuals and the regional population within an 80 km radius of the facility. Only airborne releases of radioactive materials are considered: releases to surface water and to groundwater are not addressed in MILDOS. This code is multi-purposed and can be used to evaluate population doses for NEPA assessments, maximum individual doses for predictive 40 CFR 190 compliance evaluations, or maximum offsite air concentrations for predictive evaluations of 10 CFR 20 compliance. Emissions of radioactive materials from fixed point source locations and from area sources are modeled using a sector-averaged Gaussian plume dispersion model, which utilizes user-provided wind frequency data. Mechanisms such as deposition of particulates, resuspension. radioactive decay and ingrowth of daughter radionuclides are included in the transport model. Annual average air concentrations are computed, from which subsequent impacts to humans through various pathways are computed. Ground surface concentrations are estimated from deposition buildup and ingrowth of radioactive daughters. The surface concentrations are modified by radioactive decay, weathering and other environmental processes. The MILDOS Computer Code allows the user to vary the emission sources as a step function of time by adjustinq the emission rates. which includes shutting them off completely. Thus the results of a computer run can be made to reflect changing processes throughout the facility's operational lifetime. The pathways considered for individual dose commitments and for population impacts are: Inhalation External exposure from ground concentrations External exposure from cloud immersion Ingestioo of vegetables Ingestion of meat Ingestion of milk Dose commitments are calculated using dose conversion factors, which are ultimately based on recommendations of the International Commission on Radiological Protection (ICRP). These factors are fixed internally in the code, and are not part of the input option. Dose commitments which are available from the code are as follows: Individual dose commitments for use in predictive 40 CFR 190 compliance evaluations (Radon and short-lived daughters are excluded) Total individual dose commitments (impacts from all available radionuclides are considered) Annual population dose commitments (regional, extraregional, total and cummulative). This model is primarily designed for uranium mill facilities, and should not be used for operations with different radionuclides or processes.

Strange, D. L.; Bander, T. J.

1981-04-01T23:59:59.000Z

363

Liquid Cryogen Absorber for MICE  

E-Print Network (OSTI)

the absorber body, its heat exchanger, the hydrogen system,the absorber. The heat exchanger pipes (used for absorberextended surface. The heat exchanger built into the absorber

2005-01-01T23:59:59.000Z

364

Liquid Hydrogen Absorber for MICE  

E-Print Network (OSTI)

REFERENCES Figure 5: Liquid hydrogen absorber and test6: Cooling time of liquid hydrogen absorber. Eight CernoxLIQUID HYDROGEN ABSORBER FOR MICE S. Ishimoto, S. Suzuki, M.

Ishimoto, S.

2010-01-01T23:59:59.000Z

365

Patient radiation dose in prospectively gated axial CT coronary angiography and retrospectively gated helical technique with a 320-detector row CT scanner  

Science Conference Proceedings (OSTI)

Purpose: The aim of this study was to evaluate radiation dose to patients undergoing computed tomography coronary angiography (CTCA) for prospectively gated axial (PGA) technique and retrospectively gated helical (RGH) technique. Methods: Radiation doses were measured for a 320-detector row CT scanner (Toshiba Aquilion ONE) using small sized silicon-photodiode dosimeters, which were implanted at various tissue and organ positions within an anthropomorphic phantom for a standard Japanese adult male. Output signals from photodiode dosimeters were read out on a personal computer, from which organ and effective doses were computed according to guidelines published in the International Commission on Radiological Protection Publication 103. Results: Organs that received high doses were breast, followed by lung, esophagus, and liver. Breast doses obtained with PGA technique and a phase window width of 16% at a simulated heart rate of 60 beats per minute were 13 mGy compared to 53 mGy with RGH technique using electrocardiographically dependent dose modulation at the same phase window width as that in PGA technique. Effective doses obtained in this case were 4.7 and 20 mSv for the PGA and RGH techniques, respectively. Conversion factors of dose length product to the effective dose in PGA and RGH were 0.022 and 0.025 mSv mGy{sup -1} cm{sup -1} with a scan length of 140 mm. Conclusions: CTCA performed with PGA technique provided a substantial effective dose reduction, i.e., 70%-76%, compared to RGH technique using the dose modulation at the same phase windows as those in PGA technique. Though radiation doses in CTCA with RGH technique were the same level as, or some higher than, those in conventional coronary angiography (CCA), the use of PGA technique reduced organ and effective doses to levels less than CCA except for breast dose.

Seguchi, Shigenobu; Aoyama, Takahiko; Koyama, Shuji; Fujii, Keisuke; Yamauchi-Kawaura, Chiyo [Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan) and Department of Medical Technology, Nagoya Daini Red Cross Hospital, Myouken-chou, Showa-ku, Nagoya 466-8650 (Japan); Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan); Section of Radiological Protection, National Institute of Radiological Sciences, Anagawa, Inage-ku, Chiba 263-8555 (Japan); Graduate School of Medicine, Nagoya University, Daikominami, Higashi-ku, Nagoya 461-8673 (Japan)

2010-11-15T23:59:59.000Z

366

Epothilone B Confers Radiation Dose Enhancement in DAB2IP Gene Knock-Down Radioresistant Prostate Cancer Cells  

Science Conference Proceedings (OSTI)

Purpose: In metastatic prostate cancer, DOC-2/DAB2 interactive protein (DAB2IP) is often downregulated and has been reported as a possible prognostic marker to predict the risk of aggressive prostate cancer (PCa). Our preliminary results show that DAB2IP-deficient PCa cells are radioresistant. In this study, we investigated the anticancer drug Epothilone B (EpoB) for the modulation of radiosensitivity in DAB2IP-deficient human PCa cells. Methods and Materials: We used a stable DAB2IP-knock down human PCa cell line, PC3 shDAB2IP, treated with EpoB, ionizing radiation (IR), or the combined treatment of EpoB and IR. The modulation of radiosensitivity was determined by surviving fraction, cell cycle distribution, apoptosis, and DNA double-strand break (DSB) repair. For in vivo studies, the PC3shDAB2IP xenograft model was used in athymic nude mice. Results: Treatment with EpoB at IC{sub 50} dose (33.3 nM) increased cellular radiosensitivity in the DAB2IP-deficient cell line with a dose enhancement ratio of 2.36. EpoB delayed the DSB repair kinetics after IR and augmented the induction of apoptosis in irradiated cells after G{sub 2}/M arrest. Combined treatment of EpoB and radiation enhanced tumor growth delay with an enhancement factor of 1.2. Conclusions: We have demonstrated a significant radiation dose enhancement using EpoB in DAB2IP-deficient prostate cancer cells. This radiosensitization can be attributed to delayed DSB repair, prolonged G{sub 2} block, and increased apoptosis in cells entering the cell cycle after G{sub 2}/M arrest.

Kong Zhaolu [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Institute of Radiation Medicine, Fudan University, Shanghai (China); Raghavan, Pavithra [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Xie Daxing [Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Boike, Thomas [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Burma, Sandeep; Chen, David [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States); Chakraborty, Arup [College of Pharmacy, University of Southern Nevada, Henderson, NV (United States); Hsieh, Jer-Tsong [Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States); Graduate Institute of Cancer Biology, China Medical University, Taichung, Taiwan (China); Saha, Debabrata, E-mail: debabrata.saha@utsouthwestern.ed [Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, TX (United States); Simmons Comprehensive Cancer Center, 2201 Inwood Road, Dallas, TX 75390 (United States)

2010-11-15T23:59:59.000Z

367

Design of a Transpired Air Heating Solar Collector with an Inverted Perforated Absorber and Asymmetric Compound Parabolic Concentrator.  

E-Print Network (OSTI)

?? absorber and an asymmetric compound parabolic concentrator was applied to increase the intensity of solar radiation incident on the perforated absorber. A 2D ray (more)

Shams, Nasif

2013-01-01T23:59:59.000Z

368

NCRP Forty-Eighth Annual Meeting: Radiation Dose and the Impacts on Exposed Populations  

SciTech Connect

This is a brief article for the Health Physics Newsletter describing the presentations made at the 2013 annual meeting of the National Council on Radiation Protection and Measurements 11-12 March 2013 in Bethesda, MD.

Napier, Bruce A.

2013-04-01T23:59:59.000Z

369

The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response  

NLE Websites -- All DOE Office Websites (Extended Search)

The Circadian Rhythm, A Continuous Transcription-Translation Feedback Loop, Contributes to Low-Dose Radiation-Induced Radioadaptive Response Aris Alexandrou and Jian Jian Li Department of Radiation Oncology, the University of California Davis, Sacramento, California, 95817 The initiation of the circadian rhythm field occurred when the Takahashi group defined a mutation in the mouse gene "Clock" and cloned the circadian locomotor output cycles kaput (Clock) in the mid- 1990's (1-3). Currently more than a dozen clock genes have been identified (3-4). Disruptions in the circadian rhythm via changes in environmental conditions, such as, diet, temperature, and night/day hours lead to the pathogenesis of a multitude of diseases, such as, cancer, diabetes mellitus,

370

Low Dose Radiation Research Program: Kanokporn Noy Rithidech, Ph.D.  

NLE Websites -- All DOE Office Websites (Extended Search)

Kanokporn Noy Rithidech, Ph.D. Kanokporn Noy Rithidech, Ph.D. University of New York at Stony Brook Currently Funded Projects Induction of Genomic Instability In vivo by Low Doses of 137Cs Gamma Rays Technical Abstracts 2006 Workshop: No Evidence for In Vivo Induction of Genomic Instability in Bone Marrow Cells Collected from Mice Exposed to Low-Dose 137CS γ Rays Rithidech, K.N., Loetchutinat, C., Honikel, L., and Whorton, E.B. 2005 Workshop: Induction of Genomic Instability in Vivo by Low Doses of 137Cs γ rays. Rithidech, K.N., Leotchutinat, C., Honikel, L., Simon, S.R. and Whorton, E.B. 2003 Workshop: Induction of Genomic Instability in vivo by Low Doses of 137Cs y rays Rithidech. K., Whorton, E.B., Tungjai, M., Ar-Bab, E., Simon, S.R. Tawde, M. and Anderson, C.W. 2002 Workshop: Induction of Genomic Instability In vivo by Low Doses of 137Cs gamma rays.

371

The risk equivalent of an exposure to-, versus a dose of radiation  

SciTech Connect

The long-term potential carcinogenic effects of low-level exposure (LLE) are addressed. The principal point discussed is linear, no-threshold dose-response curve. That the linear no-threshold, or proportional relationship is widely used is seen in the way in which the values for cancer risk coefficients are expressed - in terms of new cases, per million persons exposed, per year, per unit exposure or dose. This implies that the underlying relationship is proportional, i.e., ''linear, without threshold''. 12 refs., 9 figs., 1 tab.

Bond, V.P.

1986-01-01T23:59:59.000Z

372

Low Dose Radiation Research Program: Modeling the Physics of Damage Cluster  

NLE Websites -- All DOE Office Websites (Extended Search)

Modeling the Physics of Damage Cluster Formation in a Cellular Environment Modeling the Physics of Damage Cluster Formation in a Cellular Environment Larry Toburen East Carolina University Why This Project Modern tools of radiobiology are leading to many new discoveries regarding how cells and tissues respond to radiation exposure. We can now irradiate single cells and observe responses in adjacent cells. We can also measure clusters of radiation damage produced in DNA. The primary tools available to describe the initial spatial pattern of damage formed by the absorption of ionizing radiation are based on (MC) Monte Carlo simulations of the structure of charged particle tracks. Although many MC codes exist and considerable progress is being made in the incorporation of detailed macromolecular target structures into these codes, much of the interaction

373

Methods for absorbing neutrons  

DOE Patents (OSTI)

A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

Guillen, Donna P. (Idaho Falls, ID); Longhurst, Glen R. (Idaho Falls, ID); Porter, Douglas L. (Idaho Falls, ID); Parry, James R. (Idaho Falls, ID)

2012-07-24T23:59:59.000Z

374

Externally tuned vibration absorber  

DOE Patents (OSTI)

A vibration absorber unit or units are mounted on the exterior housing of a hydraulic drive system of the type that is powered from a pressure wave generated, e.g., by a Stirling engine. The hydraulic drive system employs a piston which is hydraulically driven to oscillate in a direction perpendicular to the axis of the hydraulic drive system. The vibration absorbers each include a spring or other resilient member having one side affixed to the housing and another side to which an absorber mass is affixed. In a preferred embodiment, a pair of vibration absorbers is employed, each absorber being formed of a pair of leaf spring assemblies, between which the absorber mass is suspended.

Vincent, Ronald J. (Latham, NY)

1987-09-22T23:59:59.000Z

375

Liquid Cryogen Absorber for MICE  

E-Print Network (OSTI)

through a gravity feed heat pipe that insures that thethe absorber. The heat exchanger pipes (used for absorber

2005-01-01T23:59:59.000Z

376

Effect of low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice  

NLE Websites -- All DOE Office Websites (Extended Search)

low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice low-dose, low-LET γ-radiation and BaP injection on pulmonary immunity in A/J mice K. Gott, V. Gonzales, M. Makvandi, N. Kikendall, A. Monier, E. Maloy, C. Rietz, B. Scott and J. Wilder. Lovelace Respiratory Research Institute, Albuquerque, NM Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response (Nowosielska et al., 2006), presumably via epigenetic pathways (Scott et al., 2009) and has been implicated as suppressing both alpha-radiation-induced and smoking-related lung cancer (Scott et al. 2009). One of the hypothesized adaptive-response mechanisms by which LDR does so is by activating immune cell function in the lung, which would then increase their anti-cancer surveillance

377

Low-dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell phenotype of A/J mice  

NLE Websites -- All DOE Office Websites (Extended Search)

dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell dose, low-LET γ-radiation alters carcinogen-induced splenic cytokine production and immune cell phenotype of A/J mice. V. Gonzales, K. Gott, M. Makvandi, N. Kikendall, A. Monier, E. Maloy, C. Rietz, B. Scott and J. Wilder. Lovelace Respiratory Research Institute, Albuquerque, NM. Introduction: Low-dose, low-linear-energy-transfer (LET) radiation (LDR; < 100 mGy) activates the immune response, presumably via epigenetic pathways (Scott et al. 2009) and may lead to cancer suppression (Nowosielska et al. 2006). One of the mechanisms by which it might do so is by altering the cytokines produced after carcinogen and/or radiation exposure. Alternatively, LDR may activate

378

Inference of Causal Networks from Time-course Transcription Data in Response to a2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose  

NLE Websites -- All DOE Office Websites (Extended Search)

Causal Networks from Time-course Transcription Data in Response to a Causal Networks from Time-course Transcription Data in Response to a 2 Gy Challenge Dose of Ionizing Radiation with or without a 10 cGy Priming Dose Kai Zhang, Ju Han, Torsten Groesser, Priscilla Cooper, and Bahram Parvin Lawrence Berkeley National Laboratory Goal: To elucidate temporal-dependent gene templates, causal networks, and underlying biological processes that can be inferred in response to a 10 cGy priming dose with or without a later higher challenged dose. Background and significance: Mechanistic inference of regulatory network can provide new insights into radiation systems biology. The main challenge continues to be high dimensionality of data, complex network architecture and limited knowledge of biological processes.

379

Energy Absorbing Material  

To overcome limitations with cellular silicone foams, LLNL innovators have developed a new 3D energy absorbing material with tailored/engineered ...

380

Genetic susceptibility to low-dose ionizing radiation in the mouse mammary glandas a means of understanding human risk for breast cancer  

NLE Websites -- All DOE Office Websites (Extended Search)

susceptibility to low-dose ionizing radiation in the mouse mammary gland susceptibility to low-dose ionizing radiation in the mouse mammary gland as a means of understanding human risk for breast cancer Antoine M. Snijders 1 , Francesco Marchetti 1 , Ju Han 1 , Sandhya Bhatnagar 1 , Nadire Duru 1 , Zhi Hu 1 , Jian-Hua Mao 1 , Mina Bissell 1 , Joe Gray 1,2 , Gary H. Karpen 1 , Priscilla K. Cooper 1 and Andrew J. Wyrobek 1 1 Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 2 Current affiliation: Biomedical Engineering, Oregon Health Science Univ, Portland, OR Goal: Our goal is to develop an in vivo mechanistic model of genetic variation in the low-dose damage responses of mammary glands using inbred mice known to vary in their sensitivity to low-dose induced mammary gland cancer, and to develop molecular predictors for susceptibility or resistance to low-dose induced breast cancer.

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381

Recommendations to the Technical Steering Panel regarding approach for estimating individual radiation doses resulting from releases of radionuclides to the Columbia River  

Science Conference Proceedings (OSTI)

At the direction of the Technical Steering Panel (TSP) of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle staff have reviewed and analyzed available data regarding possible historical radiation doses to individuals resulting from radionuclide releases to the Columbia River. The objective of this review was to recommend to the TSP the spatial and temporal scope and level of effort on Columbia River work to most effectively extend work performed in Phase I of the project (PNL 1991a, PNL 1991b) to meet the project objectives. A number of options were analyzed. Four stretches of the Columbia River and adjacent Pacific coastal waters were defined and investigated for four time periods. Radiation doses arising from ten potentially major exposure pathways were evaluated for each of the time/location combinations, and several alternative methods were defined for estimating the doses from each pathway. Preliminary cost estimates were also developed for implementing dose estimation activities for each of the possible combinations.

Napier, B.A.; Brothers, A.J.

1992-07-01T23:59:59.000Z

382

Recommendations to the Technical Steering Panel regarding approach for estimating individual radiation doses resulting from releases of radionuclides to the Columbia River. Volume 1, Recommendations  

Science Conference Proceedings (OSTI)

At the direction of the Technical Steering Panel (TSP) of the Hanford Environmental Dose Reconstruction (HEDR) Project, Battelle staff have reviewed and analyzed available data regarding possible historical radiation doses to individuals resulting from radionuclide releases to the Columbia River. The objective of this review was to recommend to the TSP the spatial and temporal scope and level of effort on Columbia River work to most effectively extend work performed in Phase I of the project (PNL 1991a, PNL 1991b) to meet the project objectives. A number of options were analyzed. Four stretches of the Columbia River and adjacent Pacific coastal waters were defined and investigated for four time periods. Radiation doses arising from ten potentially major exposure pathways were evaluated for each of the time/location combinations, and several alternative methods were defined for estimating the doses from each pathway. Preliminary cost estimates were also developed for implementing dose estimation activities for each of the possible combinations.

Napier, B.A.; Brothers, A.J.

1992-07-01T23:59:59.000Z

383

MO?F?103?01: Estimating Risk of Low Radiation Doses  

Science Conference Proceedings (OSTI)

Several articles in the medical literature over the past few years have predicted thousands of cancers and cancer deaths annually in the US population caused by radiation exposures from medical imaging. The predictions are derived from risk estimates in the National Academy of Sciences BEIR VII report. These risk estimates are highly speculative with wide confidence intervals

2013-01-01T23:59:59.000Z

384

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3 3 METHODS DERIVATION MODULE 3: METHODS DERIVATION DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M3-1 1 Introduction and Basis for the Approach The Department of Energy (DOE) currently has in place a radiation dose limit of 1 rad/d (10 mGy/d) for the protection of aquatic organisms (DOE Order 5400.5), and has proposed dose limits for both aquatic and terrestrial organisms. These limits are: 1 rad/d (10 mGy/d) for aquatic animals; 1 rad/d (10 mGy/d) for terrestrial plants; and 0.1 rad/d (1 mGy/d) for terrestrial animals. Because the biota protection limits are dose-based, a calculational method is needed to demonstrate compliance. In theory, derived radionuclide concentration limits for environmental media (e.g., Biota Concentration Guides, BCGs, for water, sediment, or soil) provide a relatively straightforward and simple means to do so. However, because of the

385

An Absorbed-Dose/Dose-Rate Dependence for the Alanine ...  

Science Conference Proceedings (OSTI)

... Natl. Inst. Stand. Technol. 99, 121-141 (1994). [3] JC Humphreys, JM Puhl, SM Seltzer, WL McLaughlin, MF Desrosiers, DL Bensen, and ML Walker ...

2008-05-06T23:59:59.000Z

386

Low Dose Radiation Research Program: 12.5 keV Xray Microbeam Bystander  

NLE Websites -- All DOE Office Websites (Extended Search)

12.5 keV Xray Microbeam Bystander Studies With Human Mammary 12.5 keV Xray Microbeam Bystander Studies With Human Mammary Epithelial Cells and Fibroblasts Authors: E. A. Blakely1, R. I. Schwarz1, A. C. Thompson2, K. A. Bjornstad1, P. Y. Chang1,3 C.J. Rosen1, and D. Sudar1 Institutions: Divisions of 1Life Sciences and 2Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA. and 3SRI International, Menlo Park, CA. We are using a novel x-ray Microprobe Beamline at the Advanced Light Source (ALS) at LBNL to investigate bystander effects of low doses in well characterized human mammary epithelial cells (HMEC) and human skin fibroblasts (HSF). The ALS facility is capable of producing a beam of 12.5 keV x-rays with a focussed spot size of __m_ and a wide range of doses and dose-rates. Unlike normal x-ray sources, this beam has a very small background of either low-

387

Radiation dose assessments to support evaluations of radiological control levels for recycling or reuse of materials and equipment  

Science Conference Proceedings (OSTI)

Pacific Northwest Laboratory is providing Environmental Protection Support and Assistance to the USDOE, Office of Environmental Guidance. Air, Water, and Radiation Division. As part of this effort, PNL is collecting data and conducting technical evaluations to support DOE analyses of the feasibility of developing radiological control levels for recycling or reuse of metals, concrete, or equipment containing residual radioactive contamination from DOE operations. The radiological control levels will be risk-based, as developed through a radiation exposure scenario and pathway analysis. The analysis will include evaluation of relevant radionuclides, potential mechanisms of exposure, and both health and non-health-related impacts. The main objective of this report is to develop a methodology for establishing radiological control levels for recycle or reuse. This report provides the results of the radiation exposure scenario and pathway analyses for 42 key radionuclides generated during DOE operations that may be contained in metals or equipment considered for either recycling or reuse. The scenarios and information developed by the IAEA. Application of Exemption Principles to the Recycle and Reuse of Materials from Nuclear Facilities, are used as the initial basis for this study. The analyses were performed for both selected worker populations at metal smelters and for the public downwind of a smelter facility. Doses to the public downwind were estimated using the US (EPA) CAP88-PC computer code with generic data on atmospheric dispersion and population density. Potential non-health-related effects of residual activity on electronics and on film were also analyzed.

Hill, R.L.; Aaberg, R.L.; Baker, D.A.; Kennedy, W.E. Jr.

1995-07-01T23:59:59.000Z

388

Low Dose Radiation Induced DNA Damage Signaling and Repair Responses in  

NLE Websites -- All DOE Office Websites (Extended Search)

Induced DNA Damage Signaling and Repair Responses in Induced DNA Damage Signaling and Repair Responses in Human 3-Dimensional Skin Model System Yanrong Su, Jarah Meador and Adayabalam S. Balajee Center for Radiological Research, College of Physicians and Surgeons, Columbia University, 630 West, 168th Street, New York, NY 10032. Exposure to ionizing radiation (IR) inflicts a wide variety of lesions in the genomic DNA. Among them, DNA double strand break (DSB) is considered to be the critical lesion for most of the deleterious radiation effects including carcinogenesis. Much of our knowledge on induction and repair kinetics of DSB has come from studies in two dimensional cell culture systems. However, the damage signaling and repair responses to DSB in tissue microenvironment are largely unknown. Knowledge of tissue responses to

389

Monte Carlo Simulations Of The Dose Distributions From Carbon Microbeams Used In An Experimental Radiation Therapy Method  

SciTech Connect

Recent upgrades of the MCNPX Monte Carlo code include transport of heavy ions. We employed the new code to simulate the energy and dose distributions produced by carbon beams in rabbit's head in and around a brain tumor. The work was within our experimental technique of interlaced carbon microbeams, which uses two 90 deg. arrays of parallel, thin planes of carbon beams (microbeams) interlacing to produce a solid beam at the target. A similar version of the method was earlier developed with synchrotron-generated x-ray microbeams. We first simulated the Bragg peak in high density polyethylene and other materials, where we could compare the calculated carbon energy deposition to the measured data produced at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The results showed that new MCNPX code gives a reasonable account of the carbon beam's dose up to {approx}200 MeV/nucleon beam energy. At higher energies, which were not relevant to our project, the model failed to reproduce the Bragg-peak's extent of increasing nuclear breakup tail. In our model calculations we determined the dose distribution along the beam path, including the angular straggling of the microbeams, and used the data for determining the optimal values of beam spacing in the array for producing adequate beam interlacing at the target. We also determined, for the purpose of Bragg-peak spreading at the target, the relative beam intensities of the consecutive exposures with stepwise lower beam energies, and simulated the resulting dose distribution in the spread out Bragg-peak. The details of the simulation methods used and the results obtained are presented.

Dioszegi, I. [Nonproliferation and National Security Department, Brookhaven National Laboratory, Upton, New York 11973 (United States); Rusek, A.; Chiang, I. H. [NASA Space Radiation Laboratory, Brookhaven National Laboratory, Upton, NY 11973 (United States); Dane, B. R. [Medical School, State University of New York at Stony Brook, Stony Brook, NY 11794 (United States); Meek, A. G. [Department of Radiation Oncology, State University of New York at Stony Brook, Stony Brook, NY 11794 (United States); Dilmanian, F. A. [Department of Radiation Oncology, State University of New York at Stony Brook, Stony Brook, NY 11794 (United States); Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)

2011-06-01T23:59:59.000Z

390

Advanced neutron absorber materials  

DOE Patents (OSTI)

A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

Branagan, Daniel J. (Idaho Falls, ID); Smolik, Galen R. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

391

Evaluation of S-values and dose distributions for {sup 90}Y, {sup 131}I, {sup 166}Ho, and {sup 188}Re in seven lobes of the rat liver  

Science Conference Proceedings (OSTI)

Purpose: Rats have been widely used in radionuclide therapy research for the treatment of hepatocellular carcinoma (HCC). This has created the need to assess rat liver absorbed radiation dose. In most dose estimation studies, the rat liver is considered as a homogeneous integrated target organ with a tissue composition assumed to be similar to that of human liver tissue. However, the rat liver is composed of several lobes having different anatomical and chemical characteristics. To assess the overall impact on rat liver dose calculation, the authors use a new voxel-based rat model with identified suborgan regions of the liver. Methods: The liver in the original cryosectional color images was manually segmented into seven individual lobes and subsequently integrated into a voxel-based computational rat model. Photon and electron particle transport was simulated using the MCNPX Monte Carlo code to calculate absorbed fractions and S-values for {sup 90}Y, {sup 131}I, {sup 166}Ho, and {sup 188}Re for the seven liver lobes. The effect of chemical composition on organ-specific absorbed dose was investigated by changing the chemical composition of the voxel filling liver material. Radionuclide-specific absorbed doses at the voxel level were further assessed for a small spherical hepatic tumor. Results: The self-absorbed dose for different liver lobes varied depending on their respective masses. A maximum difference of 3.5% was observed for the liver self-absorbed fraction between rat and human tissues for photon energies below 100 keV. {sup 166}Ho and {sup 188}Re produce a uniformly distributed high dose in the tumor and relatively low absorbed dose for surrounding tissues. Conclusions: The authors evaluated rat liver radiation doses from various radionuclides used in HCC treatments using a realistic computational rat model. This work contributes to a better understanding of all aspects influencing radiation transport in organ-specific radiation dose evaluation for preclinical therapy studies, from tissue composition to organ morphology and activity distribution.

Xie Tianwu; Liu Qian; Zaidi, Habib [Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China) and Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074 (China); Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074 (China); Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074 (China) and Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Geneva Neuroscience Center, Geneva University, CH-1211 Geneva (Switzerland) and Department of Nuclear Medicine and Molecular Imaging, University Medical Center Gronigen, University of Groningen, 9700 RB Groningen (Netherlands)

2012-03-15T23:59:59.000Z

392

Development of a kinetic model and calculation of radiation dose estimates for sodium iodide-{sup 131}I in athyroid individuals  

SciTech Connect

The treatment for some thyroid carcinomas involves surgically removing the thyroid gland and administering the radiopharmaceutical Sodium iodide-{sup 131}I (NaI). A diagnostic dose of NaI is given to the patient to determine if remnant tissue from the gland remains or larger doses are administered in order to treat the malignant tissue. Past research regarding NaI uptake and retention in euthyroid individuals (normal functioning thyroid) reveal that radioiodine concentrates mainly in the thyroid tissue and the remaining material is excreted from the body. The majority of radioiodine in athyroid (without thyroid) individuals is also eliminated from the body; however, there has been recent evidence of a long-term retention phase for individuals with no radioiodine concentrating tissue. The general purpose of this study was to develop a kinetic model and estimate the absorbed dose to athyroid individuals regarding the distribution and retention of NaI.

Rodriguez, M.

1997-07-01T23:59:59.000Z

393

Radiological Dose Assessment 8 2003 SITE ENVIRONMENTAL REPORT8-1  

E-Print Network (OSTI)

proportional to the absorbed dose of radiation. The environmental TLDs used at BNL are composed of calcium fluoride and lithium fluoride. The TLDs' accuracy is verified by using TLDs exposed to known sources to Aquatic and Terrestrial Biota, provides the guidelines for screening methods to estimate radiological

Homes, Christopher C.

394

Patient-specific radiation dose and cancer risk estimation in CT: Part I. Development and validation of a Monte Carlo program  

SciTech Connect

Purpose: Radiation-dose awareness and optimization in CT can greatly benefit from a dose-reporting system that provides dose and risk estimates specific to each patient and each CT examination. As the first step toward patient-specific dose and risk estimation, this article aimed to develop a method for accurately assessing radiation dose from CT examinations. Methods: A Monte Carlo program was developed to model a CT system (LightSpeed VCT, GE Healthcare). The geometry of the system, the energy spectra of the x-ray source, the three-dimensional geometry of the bowtie filters, and the trajectories of source motions during axial and helical scans were explicitly modeled. To validate the accuracy of the program, a cylindrical phantom was built to enable dose measurements at seven different radial distances from its central axis. Simulated radial dose distributions in the cylindrical phantom were validated against ion chamber measurements for single axial scans at all combinations of tube potential and bowtie filter settings. The accuracy of the program was further validated using two anthropomorphic phantoms (a pediatric one-year-old phantom and an adult female phantom). Computer models of the two phantoms were created based on their CT data and were voxelized for input into the Monte Carlo program. Simulated dose at various organ locations was compared against measurements made with thermoluminescent dosimetry chips for both single axial and helical scans. Results: For the cylindrical phantom, simulations differed from measurements by -4.8% to 2.2%. For the two anthropomorphic phantoms, the discrepancies between simulations and measurements ranged between (-8.1%, 8.1%) and (-17.2%, 13.0%) for the single axial scans and the helical scans, respectively. Conclusions: The authors developed an accurate Monte Carlo program for assessing radiation dose from CT examinations. When combined with computer models of actual patients, the program can provide accurate dose estimates for specific patients.

Li Xiang; Samei, Ehsan; Segars, W. Paul; Sturgeon, Gregory M.; Colsher, James G.; Toncheva, Greta; Yoshizumi, Terry T.; Frush, Donald P. [Medical Physics Graduate Program, Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Medical Physics Graduate Program, Department of Physics, and Department of Biomedical Engineering, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States) and Department of Biomedical Engineering, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Duke Radiation Dosimetry Laboratory, Department of Radiology, Duke University Medical Center, Durham, North Carolina 27705 (United States); Duke Radiation Dosimetry Laboratory, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 (United States); Division of Pediatric Radiology, Department of Radiology, Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27710 (United States)

2011-01-15T23:59:59.000Z

395

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2 2 DETAILED GUIDANCE MODULE 2: DETAILED GUIDANCE DOE-STD-1153-2002 INTENTIONALLY BLANK DOE-STD-1153-2002 M2-1 1 The Graded Approach, Ecological Risk Assessment, and Guidance on Their Implementation in Evaluating Radiation Doses to Biota The graded approach was made available to DOE field and program elements and to external users for a trial use period beginning in July 2000 as an interim version of this technical standard. The purpose of the trial period was to give users an opportunity to become familiar with and implement the graded approach at their sites, and to have an opportunity to provide suggestions and lessons learned to the BDAC regarding any refinements and associated guidance that needed to be incorporated into the graded approach prior to finalizing the technical standard. During this trial period the graded approach received strong interest and requests from

396

DOE-STD-1153-2002; A Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1153-2002 1153-2002 July 2002 DOE STANDARD A GRADED APPROACH FOR EVALUATING RADIATION DOSES TO AQUATIC AND TERRESTRIAL BIOTA U.S. Department of Energy AREA ENVR Washington, D.C. 20585 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. This document has been reproduced from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services, U.S. Department of Energy, (800) 473-4375, fax: (301) 903-9823. Available to the public from the U.S. Department of Commerce, Technology Administration, National Technical Information Service, Springfield, VA 22161; (703) 605-6000. DOE-STD-1153-2002 iii Foreword 1. Department of Energy (DOE) activities may expose populations of plants and animals to radioactive materials in environmental media, or to radioactive materials released in waste streams. This DOE voluntary

397

Durability of Polymeric Glazing and Absorber Materials  

DOE Green Energy (OSTI)

The Solar Heating and Lighting Program has set the goal of reducing the cost of solar water heating systems by at least 50%. An attractive approach to such large cost reduction is to replace glass and metal parts with less-expensive, lighter-weight, more-integrated polymeric components. The key challenge with polymers is to maintain performance and assure requisite durability for extended lifetimes. The objective of this task is to quantify lifetimes through measurement of the optical and mechanical stability of candidate polymeric glazing and absorber materials. Polycarbonate sheet glazings, as proposed by two industry partners, have been tested for resistance to UV radiation with three complementary methods. Incorporation of a specific 2-mil thick UV-absorbing screening layer results in glazing lifetimes of at least 15 years; improved screens promise even longer lifetimes. Proposed absorber materials were tested for creep and embrittlement under high temperature, and appear adequate for planned ICS absorbers.

Jorgensen, G.; Terwilliger, K.; Bingham, C.; Milbourne, M.

2005-01-01T23:59:59.000Z

398

Program on Technology Innovation: Evaluation of Updated Research on the Health Effects and Risks Associated with Low-Dose Ionizing Radiation  

Science Conference Proceedings (OSTI)

The Electric Power Research Institute (EPRI) has performed a systematic review of recently published, peer-reviewed scientific studies in the fields of epidemiology and radiobiology that discuss health risks associated with exposure to low levels of ionizing radiation. As a result of this study, the EPRI team concludes that there is a need to re-evaluate the magnitude of dose and dose-rate effectiveness factors (DDREF), including the significant body of radiobiology data that suggests non-linear risks at...

2009-11-18T23:59:59.000Z

399

Low Dose Radiation Research Program: A Variable-Energy Soft X-Ray  

NLE Websites -- All DOE Office Websites (Extended Search)

A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of A Variable-Energy Soft X-Ray Microprobe to Investigate Mechanisms of the Radiation -Induced Bystander Effect. Authors: Melvyn Folkard, Borivoj Vojnovic, Giuseppe Schettino, Kirk Atkinson, Kevin M Prise, Barry D Michael Institutes: Gray Cancer Institute, PO Box 100, Mount Vernon Hospital, Northwood, HA6 2JR, UK For over a decade, the Gray Cancer Institute (GCI) has been actively engaged in the development and use of micro-irradiation techniques applied to radiobiological research. Our initial investigations made use of a charged-particle microbeam capable of irradiating individual cells with collimated energetic protons or 3He ions. By the end of the 1990's, a second facility had been constructed, which uses diffractive X-ray optics to focus ultrasoft X-rays to a sub-micron spot. The X-ray microprobe was

400

Low dose radiation effects of multipotent neural stem and progenitor cells  

NLE Websites -- All DOE Office Websites (Extended Search)

effects of multipotent neural stem and progenitor cells effects of multipotent neural stem and progenitor cells Charles L. Limoli, Department of Radiation Oncology, University of California, Irvine 92697-2695 Multipotent neural cells (both stem cells and their precursor cell progeny) retain their capacity to proliferate and differentiate throughout the mammalian lifespan. High numbers of these cells are located within the dentate subgranular zone (SGZ) of the hippocampus and the subventricular (SVZ) zone adjacent to the lateral ventricles, where they produce cells that can migrate away and differentiate into neurons (neurogenesis) and glia (gliogenesis). The realization that the brain contains such cells has sparked intense interest and speculation regarding their potential function. While significant data

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While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Low Dose Radiation Research Program: Real-time Study of Signal Transduction  

NLE Websites -- All DOE Office Websites (Extended Search)

Real-time Study of Signal Transduction Pathways Involving in Real-time Study of Signal Transduction Pathways Involving in Bystander Effects Using Single Nanoparticle Optics and Single Living Cell Imaging Authors: Prakash D. Nallathamby, X. Nancy Xu, Mohan Natarajan Institutions: Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, Virginia and Department of Radiation Oncology, The University of Texas Health Science Center, San Antonio, Texas The mechanisms of bystander effects remain largely unknown. Bystander responses are thought to depend on activation of cellular communication processes. Recent studies have speculated that several crucial signal transduction pathways could play a major role in bystander effects. These crucial signal transduction pathways are controlled by a coordinated

402

Method for preparing dosimeter for measuring skin dose  

DOE Patents (OSTI)

A personnel dosimeter includes a plurality of compartments containing thermoluminescent dosimeter phosphors for registering radiation dose absorbed in the wearer's sensitive skin layer and for registering more deeply penetrating radiation. Two of the phosphor compartments communicate with thin windows of different thicknesses to obtain a ratio of shallowly penetrating radiation, e.g. beta. A third phosphor is disposed within a compartment communicating with a window of substantially greater thickness than the windows of the first two compartments for estimating the more deeply penetrating radiation dose. By selecting certain phosphors that are insensitive to neutrons and by loading the holder material with neutron-absorbing elements, energetic neutron dose can be estimated separately from other radiation dose. This invention also involves a method of injection molding of dosimeter holders with thin windows of consistent thickness at the corresponding compartments of different holders. This is achieved through use of a die insert having the thin window of precision thickness in place prior to the injection molding step.

Jones, Donald E. (Idaho Falls, ID); Parker, DeRay (Idaho Falls, ID); Boren, Paul R. (Idaho Falls, ID)

1982-01-01T23:59:59.000Z

403

Community Surveys: Low Dose Radiation. Fernald, Ohio and Rocky Flats, Colorado  

SciTech Connect

This report is intended to present a basic description of the data from the two community surveys and to document the text of the questions; the methods used for the survey data collection; and a brief overview of the results. Completed surveys were conducted at local communities near the Rocky Flats, Colorado and the Fernald, Ohio sites; no survey was conducted for the Brookhaven, New York site. Fernald. The Fernald sample was randomly selected from 98% of all potential residential telephones in the townships of Ross, Morgan, and Crosby. The only telephone exchanges not used for the Fernald study had 4%, or fewer, of the holders of the telephone numbers actually living in either of the three target townships. Surveying started on July 24, 2001 and finished on August 30, 2001. A total of 399 completed interviews were obtained resulting in a CASRO response rate of 41.8%. The average length of an interview was 16.5 minutes. Rocky Flats. The sample was randomly selected from all potential residential telephones in Arvada and from 99% of the potential telephones in Westminster. Surveying started on August 10, 2001 and finished on September 25, 2001. A total of 401 completed interviews were obtained with a CASRO response rate of 32.5%. The average length of an interview was 15.7 minutes. Overall, respondents hold favorable views of science. They indicate an interest in developments in science and technology, feel that the world is better off because of science, and that science makes our lives healthier, easier, and more comfortable. However, respondents are divided on whether science should decide what is safe or not safe for themselves and their families. The majority of the respondents think that standards for exposure to radiation should be based on what science knows about health effects of radiation and on what is possible with today's technology. Although few respondents had visited the sites, most had heard or read something about Fernald or Rocky Flat s in the media. Impressions of the sites tend to be negative. Most respondents feel that overall their community would be better off without the site. However, when asked about the economic future of their community after cleanup and closure of the site, only 31-43% thought that it will be better, 47-56% thought their local economy will be about the same.

C. K. Mertz; James Flynn; Donald G. MacGregor; Theresa Satterfield; Stephen M. Johnson; Seth Tuler; Thomas Webler

2002-10-16T23:59:59.000Z

404

Lens of Eye Dose Limit Changes: Current Status of the Potential Regulatory Changes and Possible Effects on Radiation Protection Programs at Nuclear Power Plants  

Science Conference Proceedings (OSTI)

Recent research suggests that the threshold for cataract formation as a result of exposure to radiation could be lower than previously considered. The International Commission on Radiological Protection (ICRP) is now recommending a dose limit for the lens of the eye of an average of 20 mSv (2 rem) per year, equivalent to their current recommendation for Total Effective Dose Equivalent (TEDE). The Nuclear Regulatory Commission (NRC) is considering reducing the lens of the eye dose limit to 50 mSv/yr ...

2013-10-29T23:59:59.000Z

405

SOLAR RADIATION DURABILITY OF MATERIALS, COMPONENTS AND SYSTEMS FOR PHOTOVOLTAICS  

E-Print Network (OSTI)

. Discussions at the NREL PV reliability workshop in 2011 came to the conclusion that while initial performance as a function of total absorbed solar radiation dose. In a reliability engineering framework, these quantitative and published data, comparisons have been made showing the reduction of solar irradiance incident on the PV

Rollins, Andrew M.

406

Study of radiation effects on the cell structure and evaluation of the dose delivered by x-ray and {alpha}-particles microscopy  

SciTech Connect

Hard X-ray fluorescence microscopy and magnified phase contrast imaging are combined to study radiation effects on cells. Experiments were performed on freeze-dried cells at the nano-imaging station ID22NI of the European synchrotron radiation facility. Quantitative phase contrast imaging provides maps of the projected mass and is used to evaluate the structural changes due to irradiation during X-ray fluorescence experiments. Complementary to phase contrast imaging, scanning transmission ion microscopy is performed and doses of all the experiments are compared. We demonstrate the sensitivity of the proposed approach to study radiation-induced damage at the sub-cellular level.

Kosior, Ewelina; Cloetens, Peter [European Synchrotron Radiation Facility, F-38000 Grenoble (France); Deves, Guillaume; Ortega, Richard [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Bohic, Sylvain [European Synchrotron Radiation Facility, 38000 Grenoble (France); INSERM U-836 (Team 6: Synchrotron Radiation and Medical Research), Grenoble Institut of Neuroscience, F-38000 Grenoble (France)

2012-12-24T23:59:59.000Z

407

An external dose reconstruction involving a radiological dispersal device  

E-Print Network (OSTI)

Recent events have underscored the need for the United States government to provide streamlined emergency response procedures and subsequent dose estimations for personnel responding to incidents involving radioactive material. Indeed, the National Council on Radiation Protection and Measurements Report No. 138 (NCRP 2001) indicates that exposures received by first responders will be important for a number of reasons, including planning for the appropriate use of key personnel in an extended emergency situation. In response, the Department of Homeland Security has published Protective Action Guides (DHS 2006) to help minimize these exposures and associated risks. This research attempts to provide some additional radiological exposure knowledge so that an Incident Commander, with limited or no information, can make more informed decisions about evacuation, sheltering-in-place, relocation of the public, turn-back levels, defining radiation hazard boundaries, and in-field radiological dose assessments of the radiation workers, responders, and members of the public. A method to provide such insight begins with providing a model that describes the physics of radiation interactions, radiation source and geometry, collection of field measurements, and interpretation of the collected data. A Monte Carlo simulation of the model is performed so that calculated results can be compared to measured values. The results of this investigation indicate that measured organ absorbed doses inside a tissue equivalent phantom compared favorably to the derived organ absorbed doses measured by the Panasonic thermoluminescence dosimeters and with Monte Carlo â??Nâ?? Particle modeled results. Additionally, a Victoreen 450P pressurized ion chamber measured the integrated dose and these results compared well with the Panasonic right lateral TLD. This comparison indicates that the Victoreen 450P ionization chamber could potentially serve as an estimator of real-time effective dose and organ absorbed dose, if energy and angular dependence corrections could be taken into account. Finally, the data obtained in this investigation indicate that the MCNP model provided a reasonable method to determine organ absorbed dose and effective dose of a simulated Radiological Dispersal Device in an Inferior-Superior geometry with Na99mTcO4 as the source of radioactive material.

Hearnsberger, David Wayne

2006-12-01T23:59:59.000Z

408

Low Dose Radiation Response Curves, Networks and Pathways in Human Lymphoblastoid Cells Exposed from 1 to 10 cGy of Acute Gamma Radiation  

E-Print Network (OSTI)

R.B. Mikkelsen, Ionizing radiation-induced, mitochondria-W.K. Rorrer, P.B. Chen, Radiation-induced proliferation ofresponse genes to ionizing radiation in human lymphoblastoid

Wyrobek, A. J.

2011-01-01T23:59:59.000Z

409

DOI: 10.2203/dose-response.10-003.Cuttler COMMENTARY ON USING LNT FOR RADIATION PROTECTION AND RISK ASSESSMENT  

E-Print Network (OSTI)

? An article by Jerome Puskin attempts to justify the continued use of the linear nothreshold (LNT) assumption in radiation protection and risk assessment. In view of the substantial and increasing amount of data that contradicts this assumption; it is difficult to understand the reason for endorsing this unscientific behavior, which severely constrains nuclear energy projects and the use of CT scans in medicine. Many Japanese studies over the past 25 years have shown that low doses and low dose rates of radiation improve health in living organisms including humans. Recent studies on fruit flies have demonstrated that the original basis for the LNT notion is invalid. The Puskin article omits any mention of important reports from UNSCEAR, the NCRP and the French Academies of Science and Medicine, while citing an assessment of the Canadian breast cancer study that manipulated the data to obscure evidence of reduced breast cancer mortality following a low total dose. This commentary provides dose limits that are based on real human data, for both single and chronic radiation exposures. Jerome Puskins perspective on the use of the linear no-threshold (LNT) assumption for radiation protection and risk assessment (Puskin

unknown authors

2010-01-01T23:59:59.000Z

410

[F-18]-fluorodeoxyglucose positron emission tomography for targeting radiation dose escalation for patients with glioblastoma multiforme: Clinical outcomes and patterns of failure  

SciTech Connect

Purpose: [F-18]-fluorodeoxyglucose positron emission tomography (FDG-PET) imaging for brain tumors has been shown to identify areas of active disease. Radiation dose escalation in the treatment of glioblastoma multiforme may lead to improved disease control. Based on these premises, we initiated a prospective study of FDG-PET for the treatment planning of radiation dose escalation for the treatment of glioblastoma multiforme. Methods and Materials: Forty patients were enrolled. Patients were treated with standard conformal fractionated radiotherapy with volumes defined by MRI imaging. When patients reached a dose of 45-50.4 Gy, they underwent FDG-PET imaging for boost target delineation, for an additional 20 Gy (2 Gy per fraction) to a total dose of 79.4 Gy (n = 30). Results: The estimated 1-year and 2-year overall survival (OS) for the entire group was 70% and 17%, respectively, with a median overall survival of 70 weeks. The estimated 1-year and 2-year progression-free survival (PFS) was 18% and 3%, respectively, with a median of 24 weeks. No significant improvements in OS or PFS were observed for the study group in comparison to institutional historical controls. Conclusions: Radiation dose escalation to 79.4 Gy based on FDG-PET imaging demonstrated no improvement in OS or PFS. This study establishes the feasibility of integrating PET metabolic imaging into radiotherapy treatment planning.

Douglas, James G. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States) and Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States)]. E-mail: drjay@u.washington.edu; Stelzer, Keith J. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States); Celilo Radiation Therapy, Mid-Columbia Medical Center, The Dalles, OR (United States); Mankoff, David A. [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Tralins, Kevin S. [Department of Radiation Oncology, University of Washington Medical Center, Seattle, WA (United States); Krohn, Kenneth A. [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Muzi, Mark [Department of Nuclear Medicine, University of Washington Medical Center, Seattle, WA (United States); Silbergeld, Daniel L. [Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States); Rostomily, Robert C. [Department of Neurological Surgery, University of Washington Medical Center, Seattle, WA (United States); Scharnhorst, Jeffrey B.S. [Department of Neurology, University of Washington Medical Center, Seattle, WA (United States); Spence, Alexander M. [Department of Neurology, University of Washington Medical Center, Seattle, WA (United States)

2006-03-01T23:59:59.000Z

411

Another Look at the Influence of Absorbing Aerosols in Drops on Cloud Absorption: Large Aerosols  

Science Conference Proceedings (OSTI)

Since as early as 1969, solar absorbing aerosols inside of cloud drops have been suggested to influence cloud radiative properties. The absorbing aerosols were invoked to help explain two anomalies: 1) the maximum visible albedo of thick ...

Carynelisa Erlick; Dana Schlesinger

2008-02-01T23:59:59.000Z

412

Unglazed transpired solar collector having a low thermal-conductance absorber  

DOE Patents (OSTI)

An unglazed transpired solar collector using solar radiation to heat incoming air for distribution, comprises an unglazed absorber formed of low thermal-conductance material having a front surface for receiving the solar radiation and openings in the unglazed absorber for passage of the incoming air such that the incoming air is heated as it passes towards the front surface of the absorber and the heated air passes through the openings in the absorber for distribution. 3 figs.

Christensen, C.B.; Kutscher, C.F.; Gawlik, K.M.

1997-12-02T23:59:59.000Z

413

Unglazed transpired solar collector having a low thermal-conductance absorber  

DOE Patents (OSTI)

An unglazed transpired solar collector using solar radiation to heat incoming air for distribution, comprising an unglazed absorber formed of low thermal-conductance material having a front surface for receiving the solar radiation and openings in the unglazed absorber for passage of the incoming air such that the incoming air is heated as it passes towards the front surface of the absorber and the heated air passes through the openings in the absorber for distribution.

Christensen, Craig B. (Boulder, CO); Kutscher, Charles F. (Golden, CO); Gawlik, Keith M. (Boulder, CO)

1997-01-01T23:59:59.000Z

414

Tropical Tropospheric-Only Responses to Absorbing Aerosols  

Science Conference Proceedings (OSTI)

Absorbing aerosols affect the earths climate through direct radiative heating of the troposphere. This study analyzes the tropical tropospheric-only response to a globally uniform increase in black carbon, simulated with an atmospheric general ...

Geeta G. Persad; Yi Ming; V. Ramaswamy

2012-04-01T23:59:59.000Z

415

RADIATION DOSIMETER  

DOE Patents (OSTI)

An improvement was made in the determination of amounts of ionizing radiation, particularly low-energy beta particles of less than 1000 rad total dose by means of fluid-phase dosimeter employing a stabilized-- sensitized ferrous-ferric colorimetric system in a sulphuric acid medium. The improvement in the dosimeter consists of adding to the ferrous-ferric system in concentrations of 10/sub -2/ to 10/sup -4/M an organic compound having one or more carboxylic or equivalent groups, such compounds being capable of chelating or complexing the iron ions in the solution. Suitable sensitizing and stabilizing agents are benzoic, phthalic, salicylic, malonic, lactic, maleic, oxalic, citric, succinic, phenolic tartaric, acetic, and adipic acid, as well as other compounds which are added to the solution alone or in certain combinations. As in conventional fluid-phase dosimeters, the absorbed dosage is correlated with a corresponding change in optical density at particular wavelengths of the solution.

Balkwell, W.R. Jr.; Adams, G.D. Jr.

1960-05-10T23:59:59.000Z

416

Neutron Absorbing Alloys  

SciTech Connect

The present invention is drawn to new classes of advanced neutron absorbing structural materials for use in spent nuclear fuel applications requiring structural strength, weldability, and long term corrosion resistance. Particularly, an austenitic stainless steel alloy containing gadolinium and less than 5% of a ferrite content is disclosed. Additionally, a nickel-based alloy containing gadolinium and greater than 50% nickel is also disclosed.

Mizia, Ronald E. (Idaho Falls, ID); Shaber, Eric L. (Idaho Falls, ID); DuPont, John N. (Whitehall, PA); Robino, Charles V. (Albuquerque, NM); Williams, David B. (Bethlehem, PA)

2004-05-04T23:59:59.000Z

417

Revised estimates of electron absorbed fractions and radionuclide S-values in trabecular bone  

E-Print Network (OSTI)

The field of nuclear medicine has reached advanced stages in the use of radiopharmaceuticals for the treatment and diagnosis of innumerable maladies. However, along with the use of nuclear medicine come responsibilities inherently associated with the use of radioactive material. It is necessary to be able to calculate doses in the trabecular bone region accurately and consistently. The accurate assessment of patient dose will allow physicians to better predict the amounts of radioactivity needed for specific diagnostic and therapeutic applications. Additionally, improved calculational techniques for bone dosimetry will decrease the likelihood of overadministrations and will allow for reliable predictions of side-effects to patients. The dosimetry of this region is therefore a very important, and unfortunately complicated, area associated with the field of nuclear medicine. A new dosimetric trabecular bone model has been developed and incorporated into a Monte Carlo radiation transport code to determine electron absorbed fractions in red bone marrow and the endosteal tissue which is contained in trabecular bone. The model is based on measured omnidirectional chord length distributions through trabeculae and marrow cavities in nine skeletal locations. Absorbed fractions were calculated for the two target regions, and then estimated from these results for all other skeletal regions thought to contain red marrow. These absorbed fractions were then used to calculate S-values for a variety of beta-emitting radionuclides at each of 15 skeletal locations thought to contain red bone marrow. Absorbed fractions and S-values were calculated for sources in the marrow, on the bone surface, and in the bone volume. Comparisons were made between the new absorbed fractions and those published in ICRP Publication 30, as well as between the new S-values and those determined from the MIRDOSE2 software.

Parry, Robert Alan

1995-01-01T23:59:59.000Z

418

Cell Type-dependent Gene Transcription Profile in Three Dimensional Human Skin Tissue Model Exposed to Low Doses of Ionizing Radiation: Implications for Medical Exposures  

SciTech Connect

The concern over possible health risks from exposures to low doses of ionizing radiation has been driven largely by the increase in medical exposures, the routine implementation of X-ray backscatter devices for airport security screening, and, most recently, the nuclear incident in Japan. Due to a paucity of direct epidemiological data at very low doses, cancer risk must be estimated from high dose exposure scenarios. However, there is increasing evidence that low and high dose exposures result in different signaling events and may have different mechanisms of cancer induction. We have examined the radiation induced temporal response of an in vitro three dimensional (3D) human skin tissue model using microarray-based transcriptional profiling. Our data shows that exposure to 100 mGy of X-rays is sufficient to affect gene transcription. Cell type specific analysis showed significant changes in gene expression with the levels of > 1400 genes altered in the dermis and > 400 genes regulated in the epidermis. The two cell types rarely exhibited overlapping responses at the mRNA level. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) measurements validated the microarray data in both regulation direction and value. Key pathways identified relate to cell cycle regulation, immune responses, hypoxia, reactive oxygen signaling, and DNA damage repair. We discuss in particular the role of proliferation and emphasizing how the disregulation of cellular signaling in normal tissue may impact progression towards radiation induced secondary diseases.

Freiin von Neubeck, Claere H.; Shankaran, Harish; Karin, Norman J.; Kauer, Paula M.; Chrisler, William B.; Wang, Xihai; Robinson, Robert J.; Waters, Katrina M.; Tilton, Susan C.; Sowa, Marianne B.

2012-04-17T23:59:59.000Z

419

RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND  

Science Conference Proceedings (OSTI)

Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

Farfan, E.; Jannik, T.

2011-10-01T23:59:59.000Z

420

Radiation Dose Estimates from  

E-Print Network (OSTI)

later patented them. Hazen began working at the Hanford Site in 2002, when hexavalent chromium with telephone poles is the only human signature for 10 miles beyond the security checkpoint at the Hanford Site. Today, Hanford is the site of the "world's largest environmental cleanup project." Terry Hazen

Note: This page contains sample records for the topic "radiation absorbed dose" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Health Impacts from Acute Radiation Exposure  

SciTech Connect

Absorbed doses above1-2 Gy (100-200 rads) received over a period of a day or less lead to one or another of the acute radiation syndromes. These are the hematopoietic syndrome, the gastrointestinal (GI) syndrome, the cerebrovascular (CV) syndrome, the pulmonary syndrome, or the cutaneous syndrome. The dose that will kill about 50% of the exposed people within 60 days with minimal medical care, LD50-60, is around 4.5 Gy (450 rads) of low-LET radiation measured free in air. The GI syndrome may not be fatal with supportive medical care and growth factors below about 10 Gy (1000 rads), but above this is likely to be fatal. Pulmonary and cutaneous syndromes may or may not be fatal, depending on many factors. The CV syndrome is invariably fatal. Lower acute doses, or protracted doses delivered over days or weeks, may lead to many other health outcomes than death. These include loss of pregnancy, cataract, impaired fertility or temporary or permanent sterility, hair loss, skin ulceration, local tissue necrosis, developmental abnormalities including mental and growth retardation in persons irradiated as children or fetuses, radiation dermatitis, and other symptoms listed in Table 2 on page 12. Children of parents irradiated prior to conception may experience heritable ill-health, that is, genetic changes from their parents. These effects are less strongly expressed than previously thought. Populations irradiated to high doses at high dose rates have increased risk of cancer incidence and mortality, taken as about 10-20% incidence and perhaps 5-10% mortality per sievert of effective dose of any radiation or per gray of whole-body absorbed dose low-LET radiation. Cancer risks for non-uniform irradiation will be less.

Strom, Daniel J.

2003-09-30T23:59:59.000Z

422

Shock absorbing battery housing  

SciTech Connect

A portable battery device is provided which dampens shock incident upon the battery device such that an electrical energizable apparatus connected to the battery device is subject to reduced shock whenever the battery device receives an impact. The battery device includes a battery housing of resilient shock absorbing material injection molded around an interconnecting structure which mechanically and electrically interconnects the battery housing to an electrically energizable apparatus.

McCartney, W.J.; Jacobs, J.D.; Keil, M.J.

1984-09-04T23:59:59.000Z

423

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

Enhancement of Atmospheric Solar Heating from Forest FiresScale dependence of solar heating rates in convective cloudScale Dependence of Solar Heating Rates in Convective Cloud

Zhu, Aihua

2010-01-01T23:59:59.000Z

424

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

strong northwesterly offshore wind [Pease et al. , 1998],dusty air moves offshore blown by the easterly winds, it is

Zhu, Aihua

2010-01-01T23:59:59.000Z

425

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

fuel, biofuel and biomass combustion, organic carbon hasefficient combustion processes such as biomass burning haveincomplete combustion of fossil fuel and biomass burning. BC

Zhu, Aihua

2010-01-01T23:59:59.000Z

426

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

wind carries warm marine air mass from the Southern Hemisphere northward and brings moisture and precipitation over India

Zhu, Aihua

2010-01-01T23:59:59.000Z

427

New Gadolinium and Boron Containing Radiation Absorbing ...  

Science Conference Proceedings (OSTI)

At the capture of neutron in wide energy spectrum, the (n, ?) reaction takes place ... and Welding Conditions of Monopile and Transition for Offshore Wind Plant.

428

Radiative and climate impacts of absorbing aerosols  

E-Print Network (OSTI)

during SHADE: 1. Solar spectrum, J. Geophys. Res . , 108(sensed data in the solar spectrum, J. Geophys. Res , 106 (a scattering aerosol in the solar spectrum with a SSA=1 and

Zhu, Aihua

2010-01-01T23:59:59.000Z

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Alpha Radiation  

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Basics of Radiation Basics of Radiation Gamma Radiation and X-Rays Beta Radiation Alpha Radiation Irradiation Radioactive Contamination Definitions Detection Measurement Safety Around Radiation Sources Types of Radiation Exposure Managing Radiation Emergencies Basics of Radiation Characteristics of Alpha Radiation 1. Alpha radiation is not able to penetrate skin. 2. Alpha-emitting materials can be harmful to humans if the materials are inhaled, swallowed, or absorbed through open wounds. 3. A variety of instruments have been designed to measure alpha radiation. Special training in use of these instruments is essential for making accurate measurements. 4. A civil defense instrument (CD V-700) cannot detect the presence of radioactive materials that produce alpha radiation unless the radioactive materials also produce beta and/or gamma radiation.