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1

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

2

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

3

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

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

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

4

Low dose ionizing radiation induces tumor growth promoting factors in  

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

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

5

Low Dose Radiation Research Program: Research Highlights - Ionizing  

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

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

6

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,

7

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

8

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...

9

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...

10

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...

11

Ionizing Radiation  

Science Conference Proceedings (OSTI)

*. Bookmark and Share. Ionizing Radiation Measurements. Fees for services are located directly below the technical contacts ...

2013-04-09T23:59:59.000Z

12

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

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

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

13

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.

14

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

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

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

15

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

16

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

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

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

17

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

18

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),...

19

Ionizing Radiation Division Quality Manual  

Science Conference Proceedings (OSTI)

... 08 47020C Low-energy Photon Brachytherapy Seeds, ... Calibrated for Surface Dose Rate 10 ... Sources Calibrated for Radiation Protection Ionization ...

2012-03-08T23:59:59.000Z

20

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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

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

22

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

23

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

24

Ionizing Radiation Dosimetry  

Science Conference Proceedings (OSTI)

Ionizing Radiation Dosimetry. ... OH. US Air Force Radiation Dosimetry Laboratory, Wright-Patterson - Base, OH [100548- 0] PA. ...

2013-09-06T23:59:59.000Z

25

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

26

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...

27

Protection Against Ionizing Radiation in Extreme Radiation ...  

Science Conference Proceedings (OSTI)

Protection Against Ionizing Radiation in Extreme Radiation-resistant Microorganisms. ... Elucidated radiation protection by intracellular halides. ...

2013-05-01T23:59:59.000Z

28

Lesson 4 - Ionizing Radiation | Department of Energy  

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

4 - Ionizing Radiation 4 - Ionizing Radiation Lesson 4 - Ionizing Radiation Lesson Three showed that unstable isotopes emit energy as they become more stable. This energy is known as radiation. This lesson explores forms of radiation, where radiation is found, how we detect and measure radiation, what sources of radiation people are exposed to, whether radiation is harmful, and how we can limit our exposure. Specific topics covered in this lesson include: Types of radiation Non-ionizing Ionizing Forms of ionizing radiation Alpha particles Beta particles Gamma rays Radiation Decay chain Half-life Dose Radiation measurements Sources of radiation Average annual exposure Lesson 4 - Ionizing Radiation.pptx More Documents & Publications DOE-HDBK-1130-2008 DOE-HDBK-1130-2008 DOE-HDBK-1130-2007

29

NVLAP Ionizing Radiation Dosimetry LAP  

Science Conference Proceedings (OSTI)

Ionizing Radiation Dosimetry LAP. ... This site has been established for applicants to the accreditation program for ionizing radiation dosimetry. ...

2013-07-23T23:59:59.000Z

30

NIST Ionizing Radiation Division - 2001  

Science Conference Proceedings (OSTI)

... The Ionizing Radiation Division of the Physics Laboratory supports the ... meaningful, and compatible measurements of ionizing radiations (x rays ...

31

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

32

NIST Ionizing Radiation Division 2000 - Future Directions  

Science Conference Proceedings (OSTI)

... will enable dose-reconstruction studies for populations exposed at the natural background levels of ionizing radiation. Calibrations of Low-Energy ...

33

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

34

NIST Ionizing Radiation Division - 1998  

Science Conference Proceedings (OSTI)

TECHNICAL ACTIVITIES 1998 - NISTIR 6268 IONIZING RADIATION DIVISION. The Neutron Interferometer. The neutron ...

35

NIST Ionizing Radiation Division - 2000  

Science Conference Proceedings (OSTI)

"Technical Activities 2000" - Table of Contents, Division home page. Ionizing Radiation Division. ...

36

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

37

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.

38

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

39

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...

40

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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

Ionizing radiation detector  

DOE Patents (OSTI)

An ionizing radiation detector is provided which is based on the principal of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, L.H.

1989-06-08T23:59:59.000Z

42

Ionizing radiation detector  

DOE Patents (OSTI)

An ionizing radiation detector is provided which is based on the principle of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, Louis H. (Knoxville, TN)

1990-01-01T23:59:59.000Z

43

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 1  

Science Conference Proceedings (OSTI)

... and to determine exposure or dose-rate values ... to maximize the energy absorption of the ionizing radiation. ... the calibration of an 55 Fe low-energy x ...

44

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

45

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

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

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...

46

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

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

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...

47

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.

48

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

49

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

50

22.01 Introduction to Ionizing Radiation, Fall 2003  

E-Print Network (OSTI)

Introduction to basic properties of ionizing radiations and their uses in medicine, industry, science, and environmental studies. Discusses natural and man-made radiation sources, energy deposition and dose calculations, ...

Coderre, Jeffrey A.

51

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

52

Ionizing Radiation Injury (South Carolina)  

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

This legislation applies to employers that have more than one employee who engages in activities which involve the presence of ionizing radiation. Employers with less than three employees can...

53

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...

54

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...

55

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...

56

Alloy nanoparticle synthesis using ionizing radiation  

DOE Patents (OSTI)

A method of forming stable nanoparticles comprising substantially uniform alloys of metals. A high dose of ionizing radiation is used to generate high concentrations of solvated electrons and optionally radical reducing species that rapidly reduce a mixture of metal ion source species to form alloy nanoparticles. The method can make uniform alloy nanoparticles from normally immiscible metals by overcoming the thermodynamic limitations that would preferentially produce core-shell nanoparticles.

Nenoff, Tina M. (Sandia Park, NM); Powers, Dana A. (Albuquerque, NM); Zhang, Zhenyuan (Durham, NC)

2011-08-16T23:59:59.000Z

57

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

58

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

59

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

60

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

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

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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

NIST Ionizing Radiation Division 1999 - Future Directions  

Science Conference Proceedings (OSTI)

... to test the applicability of EPR tooth enamel retrospective dosimetry to dose assessment of background radiation. The low-dose threshold (dose ...

62

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

63

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

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

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...

64

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

65

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,

66

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...

67

NIST Ionizing Radiation Division 1999 - Current Directions  

Science Conference Proceedings (OSTI)

... effect relationships for radiation-induced stochastic ... validate the EPR dose assessment methods ... Calibration of Low-Energy Photon Brachytherapy ...

68

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

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

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...

69

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,...

70

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...

71

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

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

Impact of Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards Lawrence Berkeley National Laboratory Abstract Goal Our goal is to...

72

Impact of Low-Dose Ionizing Irradiation on Histone Modification...  

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

Low-Dose Ionizing Irradiation on Histone Modification and Chromatin Organization Hunter W. Richards, Steven D. Ayers, Shutao Cai, Yoshinori Kohwi, Gary Karpen, Sylvain Costes and...

73

Poly [1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] solutions used as low dose ionizing radiation dosimeter  

Science Conference Proceedings (OSTI)

In this work, the effect of gamma radiation on the optical properties of polymetallayne poly[1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] (Pt-DEBP) in chloroform solution is studied. The samples were irradiated at room temperature with doses from 0.01 Gy to 1 Gy using a {sup 60}Co gamma ray source. A new band at 420 nm is observed in the emission spectra, in superposition to the emission maximum at 398 nm, linearly dependent on dose. We propose to use the ratio of the emission amplitude bands as the dosimetric parameter. This method proved to be robust, accurate, and can be used as a dosimeter in medical applications.

Bronze-Uhle, E. S.; Graeff, C. F. O. [Department of Physics, FC-UNESP, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru (Brazil)] [Department of Physics, FC-UNESP, Av. Eng. Luiz Edmundo Carrijo Coube 14-01, 17033-360 Bauru (Brazil); Batagin-Neto, A.; Fernandes, D. M. [UNESP-Univ Estadual Paulista, POSMAT-Programa de Pos-Graduacao em Ciencia e Tecnologia de Materiais, Bauru, Sao Paulo (Brazil)] [UNESP-Univ Estadual Paulista, POSMAT-Programa de Pos-Graduacao em Ciencia e Tecnologia de Materiais, Bauru, Sao Paulo (Brazil); Fratoddi, I.; Russo, M. V. [Department of Chemistry, University of Rome 'Sapienza,' P.le A. Moro 5, 00185 Rome (Italy)] [Department of Chemistry, University of Rome 'Sapienza,' P.le A. Moro 5, 00185 Rome (Italy)

2013-06-17T23:59:59.000Z

74

Low Dose Radiation Research Program: Genetic Factors Affecting  

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

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

75

Effects of prenatal exposure to ionizing radiation  

SciTech Connect

Prenatal exposure to ionizing radiation induces some effects that are seen at birth and others that cannot be detected until later in life. Data from A-bomb survivors in Hiroshima and Nagasaki show a diminished number of births after exposure under 4 wk of gestational age. Although a wide array of congenital malformations has been found in animal experimentation after such exposure to x rays, in humans only small head size (exposure at 4-17 wk) and mental retardation (exposure primarily at 8-15 wk) have been observed. In Hiroshima, small head size occurred after doses of 0.10-0.19 Gy or more, and an excess of mental retardation at 0.2-0.4 Gy or more. Intelligence test scores were reduced among A-bomb survivors exposed at 8-15 wk of gestational age by 21-29 IQ points per Gy. Other effects of in-utero exposure to atomic radiation include long-lasting complex chromosome abnormalities.

Miller, R.W. (National Cancer Institute, Bethesda, MD (USA))

1990-07-01T23:59:59.000Z

76

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

77

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 ...

78

NIST Ionizing Radiation Division 1998 - Current Directions  

Science Conference Proceedings (OSTI)

... Cs gamma-ray ranges, and the low-energy photon ... beam, and a high-dose- rate Gammacell used in our radiation-processing dosimetry ...

79

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....

80

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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 Research Program: Low-Dose Dose-Response of  

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

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

82

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

83

Regulation of Annexin A2 by Ionizing Radiation in Human Skin...  

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

Annexin A2 by Ionizing Radiation in Human Skin Equivalent Culture: Does A Nuclear Annexin A2-Protein Kinase C Epsilon Complex Contribute To Reduced Cancer Risks At Low Dose...

84

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

85

THE HEALTH EFFECTS IN WOMEN EXPOSED TO LOW-LEVELS OF IONIZING RADIATION  

E-Print Network (OSTI)

and Effects of Ionizing Radiation. New York, United Nations,Effects of Ionizing Radiation (BEIR III). The EffectsLevels of Ionizing Radiation. Washington, D.C. , National

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

86

Analytical models for total dose ionization effects in MOS devices.  

DOE Green Energy (OSTI)

MOS devices are susceptible to damage by ionizing radiation due to charge buildup in gate, field and SOI buried oxides. Under positive bias holes created in the gate oxide will transport to the Si / SiO{sub 2} interface creating oxide-trapped charge. As a result of hole transport and trapping, hydrogen is liberated in the oxide which can create interface-trapped charge. The trapped charge will affect the threshold voltage and degrade the channel mobility. Neutralization of oxidetrapped charge by electron tunneling from the silicon and by thermal emission can take place over long periods of time. Neutralization of interface-trapped charge is not observed at room temperature. Analytical models are developed that account for the principal effects of total dose in MOS devices under different gate bias. The intent is to obtain closed-form solutions that can be used in circuit simulation. Expressions are derived for the aging effects of very low dose rate radiation over long time periods.

Campbell, Phillip Montgomery; Bogdan, Carolyn W.

2008-08-01T23:59:59.000Z

87

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

88

Molecular mechanisms and cellular consequences of low-dose exposure to ionizing  

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

mechanisms and cellular consequences of low-dose exposure to ionizing mechanisms and cellular consequences of low-dose exposure to ionizing radiation Andrew J. Wyrobek 1 , Francesco Marchetti 1 , Xiu Lowe 1 , Xiaochen Lu 2 , Terumi Kohwi- Shigematsu 1 , Brian Davy 1 , Thomas E. Schmid 1 , Sylvia Ahn 1 , Tarlochan Nijjar 1 Matthew A. Coleman 2 , Contact information: ajwyrobek@gmail.com 1 Life Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 2 BioSciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA. The objectives of this research are to characterize the genome-wide molecular responses to low-dose ionizing radiation (<10cGy), to identify tissue and cell-type specific differences in pathways responses, and to identify the pivotal molecular pathway responses that control risks to genome integrity and health. This project utilizes mouse in

89

Ionization of Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

We have studied an ionization of alkali-metal Rydberg atoms by blackbody radiation (BBR). The results of the theoretical calculations of ionization rates of Li, Na, K, Rb and Cs Rydberg atoms are presented. Calculations have been performed for nS, nP and nD states which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at the three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependences on n. A Cooper minimum for BBR-induced transitions between bound Rydberg states of Li has been found. The calculated ionization rates are compared with our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with ...

Beterov, I I; Ryabtsev, I I; Entin, V M; Ekers, A; Bezuglov, N N

2008-01-01T23:59:59.000Z

90

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

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 Program: Principal Program Contacts  

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

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...

93

Low Dose Radiation Research Program: Alec Moreley  

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

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....

94

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

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

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

95

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

96

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

97

Composite scintillators for detection of ionizing radiation  

DOE Patents (OSTI)

Applicant's present invention is a composite scintillator having enhanced transparency for detecting ionizing radiation comprising a material having optical transparency wherein said material comprises nano-sized objects having a size in at least one dimension that is less than the wavelength of light emitted by the composite scintillator wherein the composite scintillator is designed to have selected properties suitable for a particular application.

Dai, Sheng (Knoxville, TN); Stephan, Andrew Curtis (Knoxville, TN); Brown, Suree S. (Knoxville, TN); Wallace, Steven A. (Knoxville, TN); Rondinone, Adam J. (Knoxville, TN)

2010-12-28T23:59:59.000Z

98

Waveshifters and Scintillators for Ionizing Radiation Detection  

Science Conference Proceedings (OSTI)

Scintillation and waveshifter materials have been developed for the detection of ionizing radiation in an STTR program between Ludlum Measurements, Inc. and the University of Notre Dame. Several new waveshifter materials have been developed which are comparable in efficiency and faster in fluorescence decay than the standard material Y11 (K27) used in particle physics for several decades. Additionally, new scintillation materials useful for fiber tracking have been developed which have been compared to 3HF. Lastly, work was done on developing liquid scintillators and paint-on scintillators and waveshifters for high radiation environments.

B.Baumgaugh; J.Bishop; D.Karmgard; J.Marchant; M.McKenna; R.Ruchti; M.Vigneault; L.Hernandez; C.Hurlbut

2007-12-11T23:59:59.000Z

99

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

100

Low Dose Radiation Research Program: Aloke Chatterjee  

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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....

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101

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

102

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

103

Low Dose Radiation Program: Selected Websites  

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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...

104

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.,

105

Dosimetry for non-ionizing radiation  

SciTech Connect

Several commercially available phosphor-teflon dosimeters were subjected to thermal fade studies. The thermoluminescence dosimetry (TLD) tags were washed and air dried prior to each ionizing radiation pretreatment. Readings made over 3 weeks on the CaF2:Mn and CaF2:Dy TLD tags did not produce measurable thermal-fade characteristics for the 22 to 31/sup 0/C temperature range. Nonionizing radiation treatments were at 2.45 GHz. While the results obtained did demonstrate decreases in signal levels over time and temperature changes, the patterns were not smooth, making it impossible to establish differences in TLD readings as quantitative measures of temperature differences which could serve as measures of long-term exposures to nonionizing radiation. The authors concluded that, due to the irregularities that existed in the thermal fade characteristics, the dosimeter would not be suitable for quantifying exposures to nonionizing radiation. There was significant potential in the device, however, as an indicator of radiation leakage or exposure.

Fanslow, G.E.

1981-03-01T23:59:59.000Z

106

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

107

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

108

Low Dose Radiation Research Program: Computational Modeling of Biochemical  

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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,

109

Lung cancer mortality between 1950 and 1987 after exposure to fractionated moderate-dose-rate ionizing radiation in the Canadian fluoroscopy cohort study and a comparison with lung cancer mortality in the atomic bomb survivors study  

Science Conference Proceedings (OSTI)

Current lung cancer risk estimates after exposure to low-linear energy transfer radiation such as X rays are based on studies of people exposed to such radiation at high dose rates, for example the atomic bomb survivors. Radiobiology and animal experiments suggest that risks from exposure at low to moderate dose rates, for example medical diagnostic procedures, may be overestimated by such risk models, but data for humans to examine this issue are limited. In this paper we report on lung cancer mortality between 1950 and 1987 in a cohort of 64,172 Canadian tuberculosis patients, of whom 39% were exposed to highly fractionated multiple chest fluoroscopies leading to a mean lung radiation dose of 1.02 Sv received at moderate dose rates. These data have been used to estimate the excess relative risk per sievert of lung cancer mortality, and this is compared directly to estimates derived from 75,991 atomic bomb survivors. Based on 1,178 lung cancer deaths in the fluoroscopy study, there was no evidence of any positive association between risk and dose, with the relative risk at 1 Sv being 1.00 (95% confidence interval 0.94, 1.07), which contrasts with that based on the atomic bomb survivors, 1.60 (1.27, 1.99). The difference in effect between the two studies almost certainly did not arise by chance (P = 0.0001). This study provides strong support from data for humans for a substantial fractionation/dose-rate effect for low-linear energy transfer radiation and lung cancer risk. This implies that lung cancer risk from exposures to such radiation at present-day dose rates is likely to be lower than would be predicted by current radiation risk models based on studies of high-dose-rate exposures. 25 refs., 8 tabs.

Howe, G.R. [Univ. of Toronto, Ontario (Canada)

1995-06-01T23:59:59.000Z

110

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...

111

Low Dose Radiation Research Program: Katherine Vallis  

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

112

Low Dose Radiation Research Program: Mohan Natarajan  

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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...

113

Low Dose Radiation Research Program: Multidimensional Analysis...  

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

114

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

115

Ionizing radiation risks to satellite power systems (SPS) workers  

DOE Green Energy (OSTI)

The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment were examined. For ionizing radiation, the major concern will be late or delayed health effects, particularly the increased risk of radiation-induced cancer. The estimated lifetime risk for cancer is 0.8 to 5.0 excess deaths per 10,000 workers per rad of exposure. Thus, for example, in 10,000 workers who completed ten missions with an exposure of 40 rem per mission, 320 to 2000 additional deaths in excess of the 1640 deaths from normally occurring cancer, would be expected. These estimates would indicate a 20 to 120% increase in cancer deaths in the worker-population. The wide range in these estimates stems from the choice of the risk-projection model and the dose-response relationsip. The choice between a linear and a linear-quadratic dose-response model may alter the risk estimate by a factor of about two. The method of analysis (e.g., relative vs absolute risk model) can alter the risk estimate by an additional factor of three. Choosing different age and sex distributions can further change the estimate by another factor of up to three. The potential genetic consequences could be of significance, but at the present time, sufficient information on the age and sex distribution of the worker population is lacking for precise estimation of risk. The potential teratogenic consequences resulting from radiation are considered significant. Radiation exposure of a pregnant worker could result in developmental abnormalities.

Lyman, J.T.; Ainsworth, E.J.; Alpen, E.L.; Bond, V.; Curtis, S.B.; Fry, R.J.M.; Jackson, K.L.; Nachtwey, S.; Sondhaus, C.; Tobias, C.A.; Fabrikant, J.I.

1980-11-01T23:59:59.000Z

116

Co-Regulation among genes and pathways that are responsive to low-dose ionizing  

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Regulation among genes and pathways that are responsive to low-dose ionizing Regulation among genes and pathways that are responsive to low-dose ionizing radiation. Matthew A. Coleman 1 , Anya Krefft 1 , Francesca Pearson 1 , Leif E. Peterson 2 , Jian Jian Li 3 , Xiaowen Xin 1 , Terrence Critchlow 1 , Ilkay Altintas 4 , Bertram Ludaescher 5 and Andrew J. Wyrobek 6 . 1 Biosciences, LLNL, Livermore, CA, 94550, 2 Departments of Molecular and Human Genetics and Medicine, Baylor College of Medicine, Houston, TX, 77030, 3 School of Health Sciences, Purdue University, West Lafayette, IN, 47907. 4 San Diego Supercomputer Center, University of California, San Diego La Jolla, CA 92093. 5 Department of Computer Science, University of California, Davis, CA 95616. 6 Life Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA. 94706. Contact information: coleman16@llnl.gov

117

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

118

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

119

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

120

Low Dose Radiation Research Program: David J. Chen  

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

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:...

Note: This page contains sample records for the topic "dose ionizing radiation" 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

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

122

Identification of novel ionizing radiation signaling targets in reconstituted human skin  

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of novel ionizing radiation signaling targets in reconstituted human skin of novel ionizing radiation signaling targets in reconstituted human skin Feng Yang, Katrina M. Waters, Bobbie-Jo Webb-Robertson, Lye-Meng Markillie, Rachel M. Wirgau, Shawna M. Hengel, Ljiljana Pasa-Tolic, and David L. Stenoien. Pacific Northwest National Laboratory Our focus has been on identifying the early events that occur after low dose ionizing radiation exposure that precede and often regulate downstream events such as altered transcription, protein secretion and epigenetic regulation. Phosphorylation is one of the earliest detectible events that occurs following radiation exposure and plays important roles in multiple biological pathways including DNA damage repair, transcription, apoptosis, and cell cycle progression. Very robust

123

Low Dose Radiation Research Program: Earlier Events  

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

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,

124

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...

125

Rules and Regulations for Control of Ionizing Radiation (Arkansas) |  

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

Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) Rules and Regulations for Control of Ionizing Radiation (Arkansas) < Back Eligibility Utility Program Info State Arkansas Program Type Environmental Regulations Siting and Permitting Provider Department of Health The Rules and Regulations for Control of Ionizing Radiation are the Arkansas state laws made in accordance the federal Nuclear Regulatory Commission Rules. Any contractor with the US DOE or US Nuclear Regulatory Commission is exempt from the state laws. This set of rules and regulations basically restates the federal policy to ensure that Arkansas is in compliance with the federal standards governing nuclear energy. Specifically the State rules are equivalent to Nuclear Regulatory

126

Chronic Low Dose Radiation Effects on Radiation Sensitivity  

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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

127

Plastic packaging and burn-in effects on ionizing dose response in CMOS microcircuits  

Science Conference Proceedings (OSTI)

Results are reported from an investigation of the effects of packaging and burn-in on the post-irradiation performance of National Semiconductor 54AC02 Quad 2-input NOR gates. The test population was drawn from a single wafer fabricated in the National process qualified under Mil-Prf-38535 to an ionizing radiation hardness of 100 krads(Si). The test sample was divided between plastic and ceramic packages. Additionally, half of the plastic samples and half of the two ceramic samples received a 168 hour/125 C burn-in. Two irradiation schemes were used. The first followed Mil-Std-883 Method 1019.4 (dose rate = 50 rads(Si)/s). The second used a low dose rate (0.1 rads(Si)/s). AC, DC, transfer function and functional behavior were monitored throughout the tests. Significant differences among the package types and burn-in variations were noted with the plastic, burned-in components demonstrating enhanced degradation. They show the worst post-irradiation parameter values as well as very broad post-irradiation parameter distributions. Degradation is highly dependent upon dose rate and anneal conditions. Two different radiation induced leakage paths have been identified, and their characteristics have been correlated to variations in high dose rate and low dose rate circuit performance. Caution is recommended for system developers to ensure that radiation hardness characterization is performed for the same package/burn-in configuration to be used in the system.

Clark, S.D.; Bings, J.P. [Naval Surface Warfare Center, Crane, IN (United States). Crane Div.; Maher, M.C.; Williams, M.K.; Alexander, D.R.; Pease, R.L.

1995-12-01T23:59:59.000Z

128

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,

129

Quantitative Phosphoproteomics Identifies Filaggrin and other Targets of Ionizing Radiation in a Human Skin Model  

Science Conference Proceedings (OSTI)

Our objective here was to perform a quantitative phosphoproteomic study on a reconstituted human skin tissue to identify low and high dose ionizing radiation dependent signaling in a complex 3-dimensional setting. Application of an isobaric labeling strategy using sham and 3 radiation doses (3, 10, 200 cGy) resulted in the identification of 1113 unique phosphopeptides. Statistical analyses identified 151 phosphopeptides showing significant changes in response to radiation and radiation dose. Proteins responsible for maintaining skin structural integrity including keratins and desmosomal proteins (desmoglein, desmoplakin, plakophilin 1 and 2,) had altered phosphorylation levels following exposure to both low and high doses of radiation. A phosphorylation site present in multiple copies in the linker regions of human profilaggrin underwent the largest fold change. Increased phosphorylation of these sites coincided with altered profilaggrin processing suggesting a role for linker phosphorylation in human profilaggrin regulation. These studies demonstrate that the reconstituted human skin system undergoes a coordinated response to ionizing radiation involving multiple layers of the stratified epithelium that serve to maintain skin barrier functions and minimize the damaging consequences of radiation exposure.

Yang, Feng; Waters, Katrina M.; Webb-Robertson, Bobbie-Jo M.; Sowa, Marianne B.; Freiin von Neubeck, Claere H.; Aldrich, Joshua T.; Markillie, Lye Meng; Wirgau, Rachel M.; Gristenko, Marina A.; Zhao, Rui; Camp, David G.; Smith, Richard D.; Stenoien, David L.

2012-04-17T23:59:59.000Z

130

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

131

Low Dose Radiation Research Program: Low Dose Radiation Effects in  

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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

132

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

133

Low Dose Radiation Research Program: Thomas Weber  

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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,...

134

Low Dose Radiation Research Program: Micronutrient Deficiency...  

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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...

135

Low Dose Radiation Research Program: Universities  

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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,

136

Radiation Leukaemogenesis at Low Doses  

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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...

137

Low Dose Radiation Research Program: Research Institutions  

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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

138

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 ...

139

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 ...

140

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...

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141

Composite scintillators for detection of ionizing radiation ...  

Building Energy Efficiency; Electricity Transmission; Energy Analysis; Energy ... Fluorescent Nanoparticles for Radiation DetectionFluorescent Nanoparticles for ...

142

NIST Ionizing Radiation Division 1993 - Technical Highlights  

Science Conference Proceedings (OSTI)

... The high dose rates and tight spacing preclude the use of traditional ionometric ... the polarized 3 He, and partial fabrication of a gas-handling system ...

143

The ionizing radiation environment in space and its effects  

Science Conference Proceedings (OSTI)

The ionizing radiation environment in space poses a hazard for spacecraft and space crews. The hazardous components of this environment are reviewed and those which contribute to radiation hazards and effects identified. Avoiding the adverse effects of space radiation requires design, planning, monitoring and management. Radiation effects on spacecraft are avoided largely though spacecraft design. Managing radiation exposures of space crews involves not only protective spacecraft design and careful mission planning. Exposures must be managed in real time. The now-casting and forecasting needed to effectively manage crew exposures is presented. The techniques used and the space environment modeling needed to implement these techniques are discussed.

Adams, Jim; Falconer, David; Fry, Dan [Center for Space Plasma and Aeronomic Research (CSPAR), UA Huntsville (United States); Space Radiation Analysis Group, NASA Johnson Space Center (United States)

2012-11-20T23:59:59.000Z

144

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

145

Concerns with low-level ionizing radiation  

SciTech Connect

Populations have been studied in geographic areas of increased natural radiation, in radiation-exposed workers, in patients medically exposed, and in accidental exposures. No reproducible evidence exists of harmful effects from increases in background radiation three to ten times the usual levels. There is no increase in leukemia or other cancers among American military participants in nuclear testing, no increase in leukemia or thyroid cancer among medical patients receiving {sup 131}I for diagnosis or treatment of hypothyroidism, and no increase in lung cancer among nonsmokers exposed to increased radon in the home. The association of radiation with the atomic bomb and with excessive regulatory and health physics as-low-as-reasonably-achievable (ALARA) radiation levels practices has created a climate of fear about the dangers of radiation at any level. However, there is no evidence that radiation exposures at the levels equivalent to medical usage are harmful. The unjustified excessive concern with radiation at any level, however, precludes beneficial uses of radiation and radioactivity in medicine, science, and industry.

Yalow, R.S.

1994-12-31T23:59:59.000Z

146

POSITION STATEMENT DOCUMENTING IONIZING RADIATION EXPOSURE IN THE ELECTRONIC HEALTH RECORD  

E-Print Network (OSTI)

IEEE-USA believes that maintaining an accurate record of a patients cumulative exposure to ionizing radiation can be of substantial value for clinical, health services management and research purposes. Excessive radiation can cause cancer, skin and bone marrow disease and a variety of other diseases. Radiation exposure can come from a number of sources, both natural and manmade. Over the lifetime of the individual, medical procedures, such as X-rays, Computed Tomography (CT) scans, and isotope radiation therapy, contribute significant radiation dosages. Monitoring the use of radiological procedures, measuring the radiation dose directly, and recording the dose in the Electronic Health Record (EHR) can help assess and reduce the risk posed by excessive radiation while optimizing the diagnostic value of these procedures. With these risks and benefits in mind, IEEE-USA recommends the following: 1. Health Level Seven International (HL7), the global authority responsible for standards for interoperability of health information technology, should add the appropriate "dose object " radiation parameters, as defined in the IHE Radiology Technical Framework Supplement, Radiation Exposure Monitoring (REM), to HL7/CDA format longitudinal electronic health records (EHRs), to create a longitudinal record of a patient's exposure to radiation resulting from medical procedures. These records should note both the procedure and estimated radiation dose from each procedure. 2. The Office of the National Coordinator for Health Information Technology (ONCHIT) should make radiation dose monitoring a part of meaningful use criteria for EHRs. 3. Healthcare accreditation organizations (JCAHO, NCQA and URAC), in collaboration with the American College of Radiologists (ACR), should continue

Adopted The Ieee-usa

2011-01-01T23:59:59.000Z

147

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

148

Ionic Liquids and Ionizing Radiation: Reactivity of Highly Energetic  

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Ionizing Radiation: Reactivity of Highly Energetic Ionizing Radiation: Reactivity of Highly Energetic Species James F. Wishart J. Phys. Chem. Lett. 1, 3225-3231 (2010). [Find paper at ACS Publications] or use ACS Articles on Request View the video on this Perspective article at The Journal of Physical Chemistry Letters (5:03) Selected for the ACS Special Virtual Issue on Ionic Liquids (March 2011). Abstract: Due to their unique properties, ionic liquids present many opportunities for basic research on the interactions of radiation with materials under conditions not previously available. At the same time, there are practical applied reasons for characterizing, understanding, and being able to predict how ionic-liquid-based devices and industrial-scale systems will perform under conditions of extreme reactivity, including radiation. This

149

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

150

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

151

10.2. Protection from ionizing radiation  

Science Conference Proceedings (OSTI)

exposure will be X-ray generators and radioisotopes used in the manufacture of specimens for ... (vi) during operation the dose equivalent at any accessible surface outside the ... source in the event of the loss of electrical power. 10.2.2.2.

152

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

153

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

154

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

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p53-directed, DNA damage response pathway. The p53 protein, activated indirectly by the ATM protein kinase, transactivates target genes and thus induces cell cycle progression...

155

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

156

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

157

Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters  

SciTech Connect

Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

Fabrikant, J.I.

1982-04-01T23:59:59.000Z

158

Computational phenotype prediction of ionizing-radiation-resistant bacteria with a multiple-instance learning model  

Science Conference Proceedings (OSTI)

Ionizing-radiation-resistant bacteria (IRRB) are important in biotechnology. The use of these bacteria for the treatment of radioactive wastes is determined by their surprising capacity of adaptation to radionuclides and a variety of toxic molecules. ... Keywords: ionizing-radiation-resistant bacteria, ionizing-radiation-sensitive bacteria, multiple-instance learning, phenotypic prediction, protein sequences

Sabeur Aridhi; Mondher Maddouri; Haitham Sghaier; Engelbert Mephu Nguifo

2013-08-01T23:59:59.000Z

159

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

160

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

Note: This page contains sample records for the topic "dose ionizing radiation" from the National Library of EnergyBeta (NLEBeta).
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161

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:...

162

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

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

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...

163

Development and characterization of acrylated palm oil nanoparticles using ionizing radiation  

SciTech Connect

In this study, the utilization of radiation crosslinking methods which are known as intermolecular and intramolecular crosslinking for the formation of nanoparticles of Acrylated Palm Oil (APO) in the microemulsion system that also consists of Pluronic F-127 (PF-127) surfactant was demonstrated. This microemulsion system was subjected to the ionizing radiation i.e. gamma irradiation at different doses to form the crosslinked APO nanoparticles. The effects of radiation doses on the size of APO nanoparticles were investigated using the Dynamic Light Scattering (DLS) method and their images were viewed using the Transmission Electron Microcrospy (TEM). The Fourier Transform Infra-Red (FTIR) spectroscopy was used to characterize the chemical structure and the crosslinking conversion of carbon-carbon double bond (-C = C-) of the APO nanoparticles after irradiation. As a result, the size of the APO nanoparticle decreased when the irradiation dose increased. Reduce in size might be due to the effect of intramolecular crosslinking reaction of the APO nanoparticles during irradiation process. Meanwhile, the intramolecular -C C- crosslinking conversion percentage was increased at doses below 1kGy before decreasing at the higher dose that might due to the intermolecular crosslinking of the macromolecules. This study showed that radiation crosslinking methods of polymerization and crosslinking in the microemulsion were found to be promising for the synthesis of nanoparticles.

Tajau, Rida; Yunus, Wan Md Zin Wan; Dahlan, Khairul Zaman Mohd; Mahmood, Mohd Hilmi; Hashim, Kamaruddin [Malaysian Nuclear Agency (Nuclear Malaysia), Radiation Processing Technology Division (BTS), Bangi, 43000 Kajang, Selangor (Malaysia); Chemistry Department, Faculty of Science, University Putra Malaysia (UPM), 43400 UPM Serdang, Selangor (Malaysia); Malaysian Nuclear Agency (Nuclear Malaysia), Radiation Processing Technology Division (BTS), Bangi, 43000 Kajang, Selangor (Malaysia)

2012-11-27T23:59:59.000Z

164

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

165

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

166

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

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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.

167

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,...

168

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

169

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

170

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

171

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

172

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...

173

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

174

Development of Pattern Recognition Software for Tracks of Ionizing Radiation In Medipix2-Based  

E-Print Network (OSTI)

, and area monitors to characterize the general background radiation environment harmful to humansDevelopment of Pattern Recognition Software for Tracks of Ionizing Radiation In Medipix2-Based tool for the automated identification and classification of tracks of ionizing radiation as measured

Vilalta, Ricardo

175

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

176

Role of ATM kinase in ionizing radiation induced DNA damage response...  

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ATM kinase in ionizing radiation induced DNA damage response in human neural stemprogenitor cells and differentiated cell types Adayabalam Balajee Columbia University Medical...

177

Global methylation responses to low dose radiation exposure  

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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

178

Analysis of low dose radiation induced epigenetic modifications...  

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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...

179

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

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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...

180

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

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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...

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181

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

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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....

182

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

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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...

183

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

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

184

Low Dose Radiation Research Program: Bruce N. Ames  

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

185

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

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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...

186

Low Dose Radiation Research Program: Susan S. Wallace  

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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...

187

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

188

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

189

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

190

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

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

191

Recombining WMAP: constraints on ionizing and resonance radiation at recombination  

E-Print Network (OSTI)

We place new constraints on sources of ionizing and resonance radiation at the epoch of the recombination process using the recent CMB temperature and polarization spectra coming from WMAP. We find that non-standard recombination scenarios are still consistent with the current data. In light of this we study the impact that such models can have on the determination of several cosmological parameters. In particular, the constraints on curvature and baryon density appear to be weakly affected by a modified recombination scheme. However, it may affect the current WMAP constraints on inflationary parameters like the spectral index and its running. Physically motivated models, like those based on primordial black hole or super heavy dark matter decay, are able to provide a good fit to the current data. Future observations in both temperature and polarization will be needed to more stringently test these models.

Rachel Bean; Alessandro Melchiorri; Joe Silk

2003-06-18T23:59:59.000Z

192

CORROSION PRODUCT TRANSPORT AND DEPOSITION UNDER IONIZING RADIATION  

DOE Green Energy (OSTI)

A study was made of corrosion product transport and deposition on Zircaloy-2 and AISI 304 stainless steel in the presence and absence of ionizing radiation. Three 100-hour irradiation tests, using 2-Mev electrons from a Van de Graaff accelerator, and four 100-hour nonradiation tests were performed in 6O0 deg F pressurized water. Data from the seven runs and an additional exploratory run are presented. In addition, complete experimental procedures and descriptions of the apparatus are included. Control of pH was obtained by using H and OH form ion exchange resias for pH 7 and Li and OH form ion exchange resins for pH 10. The major conclusion to be drawn from the present work is that the deposition on Zircaloy-2 at pH 10 and 600 deg F is higher than on AISI 304 stainless steel at the same conditions. (auth)

Thomas, C.C. Jr.; Lacock, H.W.; Cadoff, H.Y. ed.

1958-12-01T23:59:59.000Z

193

Low Dose Radiation Research Program: Linking Molecular Events to Cellular  

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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

194

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

195

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:...

196

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

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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

197

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

198

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

199

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

200

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...

Note: This page contains sample records for the topic "dose ionizing radiation" from the National Library of EnergyBeta (NLEBeta).
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201

ealth physics is concerned with protecting people from the harmful effects of ionizing radiation while allowing its beneficial use in medicine, science,  

E-Print Network (OSTI)

, particularly from medical exposures and from the atomic-bomb ex- posures in Hiroshima and Nagasaki. DuringH ealth physics is concerned with protecting people from the harmful effects of ionizing radiation effects such as cancer that had been observed in populations of people receiv- ing high doses

Massey, Thomas N.

202

CELLULAR RESPONSES AT LOW DOSES OF IONIZING RADIATION  

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and tissue levels including mutation induction and carcinogenesis. Furthermore, irradiation of the cytoplasm can initiate damage to the nucleus, and irradiated single cells...

203

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...

204

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...

205

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)

206

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...

207

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,...

208

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...

209

IONIZING RADIATION RISKS TO SATELLITE POWER SYSTEMS (SPS) WORKERS  

E-Print Network (OSTI)

and A. I. Sladkova, "Radiation Levels in InterplanetaryPrognoz Satellites," Cosmic Radiation, 12_, No. 5, 716-718 (0. ArchamDeau, Mammalian Radiation Lethargy, A Disturbance

Lyman, J.T.

2010-01-01T23:59:59.000Z

210

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...

211

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...

212

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

213

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

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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...

214

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:...

215

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...

216

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...

217

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...

218

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...

219

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...

220

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...

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221

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

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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,...

222

Regulation of Annexin A2 by Ionizing Radiation in Human Skin...  

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of Annexin A2 by Ionizing Radiation in Human Skin Equivalent Culture: Does A Nuclear Annexin A2-Protein Kinase C Epsilon Complex Contribute To Reduced Cancer Risks At Low...

223

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...

224

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.,...

225

Low Dose Radiation Research Program: David Nelson  

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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...

226

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

227

Low Dose Radiation Research Program: Melvyn Folkard  

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

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,

228

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

229

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

230

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

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

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

231

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

232

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

233

Radiation-induced attenuation of high-OH optical fibers after hydrogen treatment in the presence of ionizing radiation  

DOE Green Energy (OSTI)

High purity, high-OH, optical fibers were irradiated in a hydrogen atmosphere to explore hydrogen binding into defects created by the ionizing radiation. Significant improvements in subsequent measurements of radiation-induced attenuation were observed. 18 refs., 4 figs., 2 tabs.

Lyons, P.B; Looney, L.D.

1991-01-01T23:59:59.000Z

234

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.

235

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

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

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

236

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

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

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

237

Use of ionizing radiation for fixing textile resins on wool. [Gamma rays  

SciTech Connect

Ambient-temperature treatments with ionizing radiation can be used as an alternative to conventional thermal/catalytic cure methods of fixing textile resins on wool materials. The effectiveness of the radiation-induced fixation of resins on wool has been demonstrated by machine-wash shrinkage tests on fabrics treated with a variety of commercial polymer resins.

McLaren, K.G.

1980-04-01T23:59:59.000Z

238

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

239

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.

240

Low Dose Radiation Research Program: Biologically Based Analysis of Lung  

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

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,

Note: This page contains sample records for the topic "dose ionizing radiation" 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: Frequencies of Radiation-Induced  

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

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

242

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

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.

243

Low Dose Radiation Research Program: Molecular Characterization of Survival  

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

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

244

Low Dose Radiation Research Program: Janet E. Baulch  

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

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

245

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

246

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

247

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

248

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

249

NIST Ionizing Radiat. Div. - 2004: Strategic Focus 2  

Science Conference Proceedings (OSTI)

... electronic radiation monitors ("pagers"), isotope identifier instruments ... 2003, DOE recognized this program as one of the top-ten programs relevant to ...

250

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

251

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

252

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

253

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

254

Does nitrate deposition following astrophysical ionizing radiation events pose an additional threat to amphibians?  

E-Print Network (OSTI)

It is known that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an additional stress beyond that of the heightened UVB previously considered. We have converted predicted nitrate depositions to concentration values, utilizing data from the New York State Department of Environmental Conservation Acid Rain Monitoring Network web site. Our results show that the increase in nitrate concentration in bodies of water following the most intense ionization event likely in the last billion years would not be sufficient to cause a serious additional stress on amphibian populations and may actually provide some benefit by acting as fertilizer.

Brian C. Thomas; Michelle D. Honeyman

2008-04-22T23:59:59.000Z

255

Amphibian nitrate stress as an additional terrestrial threat from astrophysical ionizing radiation events?  

E-Print Network (OSTI)

As diversity in amphibian species declines, the search for causes has intensified. Work in this area has shown that amphibians are especially susceptible to the combination of heightened UVB radiation and increased nitrate concentrations. Various astrophysical events have been suggested as sources of ionizing radiation that could pose a threat to life on Earth, through destruction of the ozone layer and subsequent increase in UVB, followed by deposition of nitrate. In this study, we investigate whether the nitrate deposition following an ionizing event is sufficiently large to cause an additional stress beyond that of the heightened UVB previously considered. We have converted predicted nitrate depositions to concentration values, utilizing data from the New York State Department of Environmental Conservation Acid Rain Monitoring Network web site. Our results show that the increase in nitrate concentration in bodies of water following the most intense ionization event likely in the last billion years would no...

Thomas, Brian C

2008-01-01T23:59:59.000Z

256

Detection of Ionizing Radiation by Plasma-Panel Sensors: Cosmic Muons, Ion Beams, and Cancer Therapy  

Science Conference Proceedings (OSTI)

The plasma panel sensor is an ionizing photon and particle radiation detector derived from PDP technology with high gain and nanosecond response. Experimental results in detecting cosmic ray muons and beta particles from radioactive sources are described along with applications including high energy and nuclear physics, homeland security and cancer therapeutics.

Friedman, Dr. Peter S. [Integrated Sensors, LLC; Ferretti, Claudio [University of Michigan; Ball, Robert [University of Michigan; Beene, James R [ORNL; Ben Moshe, M. [Tel Aviv University; Benhammou, Yan [Tel Aviv University; Chapman, J. Wehrley [University of Michigan; Levin, Daniel S. [University of Michigan; Silver, Yiftah [Tel Aviv University; Weaverdyck, Curtis [University of Michigan; Zhou, Bing [University of Michigan; Etzion, E [Tel Aviv University; Moshe, M. [Tel Aviv University; Bentefour, E [Ion Beam Applications

2012-01-01T23:59:59.000Z

257

The effects of diet and ionizing radiation on azoxymethane induced colon carcinogenesis  

E-Print Network (OSTI)

The ability of ionizing radiation to enhance colon carcinogenesis and the role of diet in this process has not been documented. We hypothesized that radiation would enhance the formation of aberrant crypt foci, ACF, known precursor lesions to colon cancer, by suppressing apoptosis and upregulating proliferation in colonocytes. Diets contained a combination of fish oil or corn oil and either pectin or cellulose. We exposed 40 male Sprague-Dawley rats to 1 Gy ionizing radiation (1 GeV Fe) 10 d prior to injection with AOM. Colons were resected at the promotion stage of carcinogenesis (7 wk post initial injection) and assayed for ACF and apoptosis. Radiation treatment increased (P=0.0327) the incidence of high multiplicity ACF (foci with four or more aberrant crypts) and decreased (P=0.0340) the apoptotic index compared to non-irradiated rats. Radiation also resulted in an increase (PACF compared to the corn oil treatment. Dietary pectin significantly increased (P=0.0204) the apoptotic index compared to cellulose treatment. These data suggest that ionizing radiation can work synergistically with AOM and increase the formation of high-multiplicity ACF, upregulate cellular proliferation and decrease apoptosis in colonocytes. The data also suggest that diets containing fish oil and pectin may protect against colon cancer by increasing apoptosis and reducing the formation of high multiplicity ACF.

Mann, John Clifford

2005-08-01T23:59:59.000Z

258

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

259

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

260

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 "dose ionizing radiation" 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

Methylation of the ATM promoter in glioma cells alters ionizing radiation sensitivity  

SciTech Connect

Glioblastomas are among the malignancies most resistant to radiation therapy. In contrast, cells lacking the ATM protein are highly sensitive to ionizing radiation. The relationship between ATM protein expression and radiosensitivity in 3 glioma cell lines was examined. T98G cells exhibited normal levels of ATM protein, whereas U118 and U87 cells had significantly lower levels of ATM and increased (>2-fold) sensitivity to ionizing radiation compared to T98G cells. The ATM promoter was methylated in U87 cells. Demethylation by azacytidine treatment increased ATM protein levels in the U87 cells and decreased their radiosensitivity. In contrast, the ATM promoter in U118 cells was not methylated. Further, expression of exogenous ATM did not significantly alter the radiosensitivity of U118 cells. ATM expression is therefore heterogeneous in the glioma cells examined. In conclusion, methylation of the ATM promoter may account for the variable radiosensitivity and heterogeneous ATM expression in a fraction of glioma cells.

Roy, Kanaklata [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Wang, Lilin [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Makrigiorgos, G. Mike [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States); Price, Brendan D. [Division of Genomic Stability and DNA Repair, Department of Radiation Oncology, Harvard Medical School, Dana-Farber Cancer Institute, 44 Binney St, Boston, MA 02115 (United States)]. E-mail: brendan_price@dfci.harvard.edu

2006-06-09T23:59:59.000Z

262

Low Dose Radiation Research Program: Robert L. Ullrich  

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

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.

263

Low Dose Radiation Research Program: Research Highlights - Collateral  

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

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

264

Low Dose Radiation Research Program: Rainer K. Sachs  

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

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

265

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

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

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

266

Low Dose Radiation Research Program: Quantitative Analysis of Connexin  

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

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

267

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

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

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

268

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

269

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

270

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

271

Low Dose Radiation Research Program: Quantification of Repair of  

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

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

272

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

273

Cosmological constraints in the presence of ionizing and resonance radiation at recombination  

E-Print Network (OSTI)

With the recent measurement of full sky cosmic microwave background polarization from WMAP, key cosmological degeneracies have been broken, allowing tighter constraints to be placed on cosmological parameters inferred assuming a standard recombination scenario. Here we consider the effect on cosmological constraints if additional ionizing and resonance radiation sources are present at recombination. We find that the new CMB data significantly improve the constraints on the additional radiation sources, with $\\log_{10}[\\epsilon_{\\alpha}] < -0.5$ and $\\log_{10}[\\epsilon_{i}] <-2.4$ at 95% c.l. for resonance and ionizing sources respectively. Including the generalized recombination scenario, however, we find that the constraints on the scalar spectral index $n_s$ are weakened to $n_s=0.98\\pm0.03$, with the $n_s=1$ case now well inside the 95% c.l.. The relaxation of constraints on tensor modes, scale invariance, dark energy and neutrino masses are also discussed.

Rachel Bean; Alessandro Melchiorri; Joe Silk

2007-01-09T23:59:59.000Z

274

Technical specifications manual for the MARK-1 pulsed ionizing radiation detection system. Volume 1  

Science Conference Proceedings (OSTI)

The MARK-1 detection system was developed by the Idaho National Engineering Laboratory for the US Department of Energy Office of Arms Control and Nonproliferation. The completely portable system was designed for the detection and analysis of intense photon emissions from pulsed ionizing radiation sources. This manual presents the technical design specifications for the MARK-1 detection system and was written primarily to assist the support or service technician in the service, calibration, and repair of the system. The manual presents the general detection system theory, the MARK-1 component design specifications, the acquisition and control software, the data processing sequence, and the system calibration procedure. A second manual entitled: Volume 2: Operations Manual for the MARK-1 Pulsed Ionizing Radiation Detection System (USDOE Report WINCO-1108, September 1992) provides a general operational description of the MARK-1 detection system. The Operations Manual was written primarily to assist the field operator in system operations and analysis of the data.

Lawrence, R.S.; Harker, Y.D.; Jones, J.L.; Hoggan, J.M.

1993-03-01T23:59:59.000Z

275

Low Dose Radiation Research Program: Characterizing Bystander Effects  

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

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

276

Low Dose Radiation Research Program: Genetic Mechanisms of Induced  

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

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

277

Exposure to ionizing radiation in the emergency department from commonly performed portable radiographs  

SciTech Connect

To accurately assess the potential hazard of exposure to ionizing radiation from portable radiographs taken in the emergency department, a study was performed to measure such radiation at different distances from the edge of an irradiated field during portable cervical-spine (pC-S), portable chest radiograph (pCXR), and portable anteroposterior-pelvis (pAP-pelvis) radiographs. For all three types of portable radiographs, radiation exposure is a function of distance from the beam. However, at 40 cm (15 inches) away from the beam during a pC-S or pCXR and at 160 cm (63 inches) from a pAP-pelvis film, exposure is minimal. At these distances one would need to be exposed to more than 1,200 such radiographs to equal background environmental ionizing radiation. Medical personnel should not have to leave a patient care area for fear of undue acute and chronic radiation exposure while portable radiographs are performed in the ED. By using protective garments and standing appropriate distances away from the patient, continuous patient care can be maintained while portable radiographs are taken in the ED.

Grazer, R.E.; Meislin, H.W.; Westerman, B.R.; Criss, E.A.

1987-04-01T23:59:59.000Z

278

Effects of Ionizing Radiation on Digital Single Event Transients in a 180-nm Fully Depleted SOI Process  

E-Print Network (OSTI)

Effects of ionizing radiation on single event transients are reported for Fully Depleted SOI (FDSOI) technology using experiments and simulations. Logic circuits, i.e. CMOS inverter chains, were irradiated with cobalt-60 ...

Keast, Craig L.

279

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

280

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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.


281

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

282

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents (OSTI)

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes insitu polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr., Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-05-03T23:59:59.000Z

283

Space charge dosimeters for extremely low power measurements of radiation in shipping containers  

DOE Patents (OSTI)

Methods and apparatus are described for space charge dosimeters for extremely low power measurements of radiation in shipping containers. A method includes in situ polling a suite of passive integrating ionizing radiation sensors including reading-out dosimetric data from a first passive integrating ionizing radiation sensor and a second passive integrating ionizing radiation sensor, where the first passive integrating ionizing radiation sensor and the second passive integrating ionizing radiation sensor remain situated where the dosimetric data was integrated while reading-out. Another method includes arranging a plurality of ionizing radiation sensors in a spatially dispersed array; determining a relative position of each of the plurality of ionizing radiation sensors to define a volume of interest; collecting ionizing radiation data from at least a subset of the plurality of ionizing radiation sensors; and triggering an alarm condition when a dose level of an ionizing radiation source is calculated to exceed a threshold.

Britton, Jr.; Charles L. (Alcoa, TN); Buckner, Mark A. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Bryan, William L. (Knoxville, TN)

2011-04-26T23:59:59.000Z

284

Low Dose Radiation Research Program: Use of Computational Modeling to  

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

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

285

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...

286

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

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

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...

287

RADIATION MONITOR CONTAINING TWO CONCENTRIC IONIZATION CHAMBERS AND MEANS FOR INSULATING THE SEPARATE CHAMBERS  

DOE Patents (OSTI)

This invention relates to a portable radiation monitor containing two concentric ionization chambers which permit the use of standard charging and reading devices. It is particularly adapted as a personnel x-ray dosimeter and to this end comprises a small thin walled, cylindrical conductor forming an inner energy dependent chamber, a small thin walled, cylindrical conductor forming an outer energy independent chamber, and polymeric insulation means which insulates said chambers from each other and holds the chambers together with exposed connections in a simple, trouble-free, and compact assembly substantially without variation in directional response. (AEC)

Braestrup, C.B.; Mooney, R.T.

1964-01-21T23:59:59.000Z

288

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

289

Gamma radiation field intensity meter  

DOE Patents (OSTI)

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1994-08-16T23:59:59.000Z

290

Gamma radiation field intensity meter  

DOE Patents (OSTI)

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1995-10-17T23:59:59.000Z

291

Gamma radiation field intensity meter  

SciTech Connect

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1995-01-01T23:59:59.000Z

292

Gamma radiation field intensity meter  

SciTech Connect

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode.

Thacker, Louis H. (Knoxville, TN)

1994-01-01T23:59:59.000Z

293

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...

294

Alterations in transcription factor binding in radioresistant human melanoma cells after ionizing radiation  

Science Conference Proceedings (OSTI)

We analyzed alterations in transcription factor binding to specific, known promoter DNA consensus sequences between irradiated and unirradiated radioresistant human melanoma (U1-Mel) cells. The goal of this study was to begin to investigate which transcription factors and DNA-binding sites are responsible for the induction of specific transcripts and proteins after ionizing radiation. Transcription factor binding was observed using DNA band-shift assays and oligonucleotide competition analyses. Confluence-arrested U1-Mel cells were irradiated (4.5 Gy) and harvested at 4 h. Double-stranded oligonucleotides containing known DNA-binding consensus sites for specific transcription factors were used. Increased DNA binding activity after ionizing radiation was noted with oligonucleotides containing the CREB, NF-kB and Sp1 consensus sites. No changes in protein binding to AP-1, AP-2, AP-3, or CTF/NF1, GRE or Oct-1 consensus sequences were noted. X-ray activation of select transcription factors, which bind certain consensus sites in promoters, may cause specific induction or repression of gene transcription. 22 refs., 2 figs.

Sahijdak, W.M.; Yang, Chin-Rang; Zuckerman, J.S.; Meyers, M.; Boothman, D.A. [Univ. of Wisconsin, Madison, WI (United States)

1994-04-01T23:59:59.000Z

295

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

296

Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe  

DOE Patents (OSTI)

An optimized examination system and method based on the Reverse Geometry X-Ray.RTM. (RGX.RTM.) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging.

Majewski, Stanislaw (Grafton, VA); Kross, Brian J. (Yorktown, VA); Zorn, Carl J. (Yorktown, VA); Majewski, Lukasz A. (Grafton, VA)

1996-01-01T23:59:59.000Z

297

Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe  

DOE Patents (OSTI)

An optimized examination system and method based on the Reverse Geometry X-Ray{trademark} (RGX{trademark}) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging. 5 figs.

Majewski, S.; Kross, B.J.; Zorn, C.J.; Majewski, L.A.

1996-10-22T23:59:59.000Z

298

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

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

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...

299

Low Dose Radiation Research Program: Research Highlights - 2010  

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

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,

300

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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.


301

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

302

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

303

Ionizing radiation downregulates ASPM, a gene responsible for microcephaly in humans  

SciTech Connect

Microcephaly is a malformation associated with in utero exposed atomic bomb survivors and can be induced in mice by fetal exposure to ionizing radiation (IR). The pathogenesis of IR-induced microcephaly, however, has not been fully understood. Our analyses of high-coverage expression profiling (HiCEP) demonstrated that the abnormal spindle-like microcephaly associated gene (ASPM) was down-regulated in irradiated human diploid fibroblasts. ASPM was recently reported as the causative gene for MCPH-5, the most common type of congenital microcephaly in humans. Here, we show that the expression of the Aspm gene was significantly reduced by IR in various human and murine cells. Additionally, Aspm was found downregulated in the irradiated fetal mouse brain, particularly in the ventricular zones. A similar suppression was observed in the irradiated neurosphere cultures. This is the first report suggesting that the suppression of Aspm by IR could be the initial molecular target leading to the future microcephaly formation.

Fujimori, Akira [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan)], E-mail: fujimora@nirs.go.jp; Yaoi, Takeshi; Ogi, Hiroshi [Department of Pathology and Applied Neurobiology, Kyoto Prefectural University of Medicine, Graduate School of Medical Sciences, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan); Wang Bing [National Institute of Radiological Sciences, Heavy-Ion Radiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Suetomi, Katsutoshi; Sekine, Emiko; Yu Dong; Kato, Takamitsu [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Takahashi, Sentaro [National Institute of Radiological Sciences, Heavy-Ion Radiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Okayasu, Ryuichi [Cellular and Molecular Biology Team, National Institute of Radiological Sciences, Heavy-Ion Radiobiology Research Group, Research Center for Charged Particle Therapy, 4-9-1 Anagawa, Inage, Chiba 263-8555 (Japan); Itoh, Kyoko; Fushiki, Shinji [Department of Pathology and Applied Neurobiology, Kyoto Prefectural University of Medicine, Graduate School of Medical Sciences, Kawaramachi Hirokoji, Kamigyo-ku, Kyoto 602-8566 (Japan)

2008-05-09T23:59:59.000Z

304

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

305

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

306

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

307

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

308

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

309

TWO-DIMENSIONAL RADIATIVE MAGNETOHYDRODYNAMIC SIMULATIONS OF THE IMPORTANCE OF PARTIAL IONIZATION IN THE CHROMOSPHERE  

Science Conference Proceedings (OSTI)

The bulk of the solar chromosphere is weakly ionized and interactions between ionized particles and neutral particles likely have significant consequences for the thermodynamics of the chromospheric plasma. We investigate the importance of introducing neutral particles into the MHD equations using numerical 2.5D radiative MHD simulations obtained with the Bifrost code. The models span the solar atmosphere from the upper layers of the convection zone to the low corona, and solve the full MHD equations with non-gray and non-LTE radiative transfer, and thermal conduction along the magnetic field. The effects of partial ionization are implemented using the generalized Ohm's law, i.e., we consider the effects of the Hall term and ambipolar diffusion in the induction equation. The approximations required in going from three fluids to the generalized Ohm's law are tested in our simulations. The Ohmic diffusion, Hall term, and ambipolar diffusion show strong variations in the chromosphere. These strong variations of the various magnetic diffusivities are absent or significantly underestimated when, as has been common for these types of studies, using the semi-empirical VAL-C model as a basis for estimates. In addition, we find that differences in estimating the magnitude of ambipolar diffusion arise depending on which method is used to calculate the ion-neutral collision frequency. These differences cause uncertainties in the different magnetic diffusivity terms. In the chromosphere, we find that the ambipolar diffusion is of the same order of magnitude or even larger than the numerical diffusion used to stabilize our code. As a consequence, ambipolar diffusion produces a strong impact on the modeled atmosphere. Perhaps more importantly, it suggests that at least in the chromospheric domain, self-consistent simulations of the solar atmosphere driven by magnetoconvection can accurately describe the impact of the dominant form of resistivity, i.e., ambipolar diffusion. This suggests that such simulations may be more realistic in their approach to the lower solar atmosphere (which directly drives the coronal volume) than previously assumed.

Martinez-Sykora, Juan; De Pontieu, Bart; Hansteen, Viggo, E-mail: j.m.sykora@astro.uio.no [Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)

2012-07-10T23:59:59.000Z

310

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...

311

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...

312

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

313

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...

314

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)

315

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

316

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

317

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...

318

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

319

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....

320

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.,...

Note: This page contains sample records for the topic "dose ionizing radiation" 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.


321

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...

322

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

323

Ionization of Sodium and Rubidium nS, nP and nD Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

Results of theoretical calculations of ionization rates of Rb and Na Rydberg atoms by blackbody radiation (BBR) are presented. Calculations have been performed for nS, nP and nD states of Na and Rb, which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependencies on n. The calculated ionization rates are compared with the results of our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with n=8-20 at 300 K. A good agreement for all states except nS with n>15 is observed. We also present the useful analytical formulae for quick estimation of BBR ionization rates of Rydberg atoms.

I. I. Beterov; D. B. Tretyakov; I. I. Ryabtsev; A. Ekers; N. N. Bezuglov

2007-02-22T23:59:59.000Z

324

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...

325

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...

326

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...

327

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...

328

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...

329

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...

330

The carcinogenic risks of low-LET and high-LET ionizing radiations  

SciTech Connect

New information is available concerning the carcinogenic effects of radiation and the implications for risk assessment and risk management. This information comes from further follow-up of the epidemiological studies of the Japanese atomic bomb survivors, patients irradiated medically for cancer and allied conditions, and workers exposed in various occupations. In the Japanese atomic bomb survivors the carcinogenic risks are estimated to be somewhat higher than previously, due to the reassessment of the atomic-bomb dosimetry, further follow-up with increase in the number of excess cancer deaths, particularly in survivors irradiated early in life, and changes in the methods of analysis to compute the age-specific risks of cancer. Because of the characteristics of the atomic bomb survivor series as regards sample size, age and sex distribution, duration for follow-up, person-years at risk, and type of dosimetry, the mortality experience of the atomic bomb survivors was selected by the UNSCEAR Committee and the BEIR V Committee as the more appropriate basis for projecting risk estimates for the general population. In the atomic bomb survivors, the dose-effect relationship for overall cancer mortality other than leukemia is consistent with linearity below 3 Gy, while the dose-effect relationship for leukemia, excluding chronic lymphatic leukemia, conforms best to a linear-quadratic function. The shape of the dose-incidence curve at low doses still remains uncertain, and the data do not rule out the possible existence of a threshold for an neoplasm. The excess relative risk of mortality from all cancers combined is estimated to be 1.39 per Gy (shielded kerma), which corresponds to an absolute risk of 10.0 excess cancer deaths per 10,000 PYGy; the relative risks is 1.41 at 1 Gy (organ-absorbed dose), and an absolute risk of 13.07 excess cancer deaths per 10,000 PYGy. 19 refs.

Fabrikant, J.I. (Lawrence Berkeley Lab., CA (USA))

1989-08-01T23:59:59.000Z

331

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

332

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 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

333

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

334

Low Dose Radiation Research Program: Howard L. Liber  

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

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.

335

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.

336

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

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

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...

337

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

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

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...

338

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

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

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....

339

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

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

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...

340

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

Note: This page contains sample records for the topic "dose ionizing radiation" 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.


341

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

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

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...

342

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

343

Low Dose Radiation Research Program: Modeling Intercellular Interactions  

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

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

344

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

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

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

345

Low Dose Radiation Research Program: Interaction between Tissue and  

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

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

346

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

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

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

347

Low Dose Radiation Research Program: Low-LET Microdosimetry Calculations  

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

Low-LET Microdosimetry Calculations Low-LET Microdosimetry Calculations Authors: W.E. Wilson, J.H. Miller, D.J. Lynch, R.R. Lewis and M. Batdorf Institutions: Washington State University, Richland, WA, USA Liquid Model Calculations of low-linear-transfer (LET) microdosimetry have been extended to condensed phase by introducing new modules into the PITS code suite. Probability tables for inelastic interactions are constructed using the Dingfelder-GSF model for liquid-water cross-sections. Dingfelder et al. 1 re-evaluated low-energy electron interactions in liquid water in terms of five excitation and five ionization channels, and without assuming any collective interactions (plasmons). We use Dingfelder’s algorithms to calculate differential energy-loss distributions for the ten channels; by

348

Gaseous Radiochemical Method for Registration of Ionizing Radiation and Its Possible Applications in Science and Industry  

E-Print Network (OSTI)

This work presents a new possibility of registration of ionizing radiation by the flowing gaseous radiochemical method (FGRM). The specified method uses the property of some solid crystalline lattice materials for a free emission of radioactive isotopes of inert gas atoms formed as a result of nuclear reactions. Generated in an ampoule of the detector, the radioactive inert gases are transported by a gas-carrier into the proportional gas counter of the flowing type, where the decay rate of the radioactive gas species is measured. This quantity is unequivocally related to the flux of particles (neutrons, protons, light and heavy ions) at the location of the ampoule. The method was used to monitor the neutron flux of the pulsed neutron target "RADEX" driven by the linear proton accelerator of INR RAS. Further progress of the FGRM may give rise to possible applications in nuclear physics, astrophysics and medicine, in the nondestructive control of fissionable materials, diagnostics of thermonuclear plasma, monitoring of fluxes and measurement of spectra of bombarding particles.

S. G. Lebedev; V. E. Yants

2005-10-06T23:59:59.000Z

349

Ionizing radiation induces IL-6-production by human fibroblasts involving activation of nuclear factor-. kappa. B  

Science Conference Proceedings (OSTI)

The authors report that human lung fibroblasts respond to X-ray treatment with release of interleukin (IL) -6. Synthesis of IL-6 upon ionizing radiation is preceded by an increase of IL-6 transcript levels resulting from transcriptional activation of the IL-6 gene. Analysis of deleted fragments of the IL-6 promoter revealed that transcriptional induction of the IL-6 promoter is due to enhanced binding activity of the transcription factor NF-kB. Although AP-1 does not participate in the rapid induction of the IL-6 promoter its binding activity is also enhanced upon XRT. In contrast to binding kinetics observed with NF-kB, AP-1 binding upon XRT. In contrast to binding kinetics observed with NF-kB- and the AP-1 recognition sequence, conferred inducibility by XRT to a heterologous promoter, with reporter gene activity being maximal 24 hours or 48 hours upon XRT, respectively. Sequential activation of two distinct transcription factors might thus contribute to synchronize transcriptional activation of different genes participating in the X-ray response.

Brach, M.A.; Gruss, H.J.; Kaisho, Tsuneyasu; Asano, Yoshinobu; Vos, Sven de; Mertelsmann, R.; Hirano, Toshio; Herrmann, F. (Univ. of Freiburg (Germany) Osaka Univ. (Japan))

1992-02-26T23:59:59.000Z

350

Low Dose Radiation Research Program: Interaction of Genome and Cellular  

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

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.

351

Low Dose Radiation Research Program: Dual Regulation of JB6 Transformation  

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

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

352

Ionization of Sodium and Rubidium nS, nP and nD Rydberg atoms by blackbody radiation  

E-Print Network (OSTI)

Results of theoretical calculations of ionization rates of Rb and Na Rydberg atoms by blackbody radiation (BBR) are presented. Calculations have been performed for nS, nP and nD states of Na and Rb, which are commonly used in a variety of experiments, at principal quantum numbers n=8-65 and at three ambient temperatures of 77, 300 and 600 K. A peculiarity of our calculations is that we take into account the contributions of BBR-induced redistribution of population between Rydberg states prior to photoionization and field ionization by extraction electric field pulses. The obtained results show that these phenomena affect both the magnitude of measured ionization rates and shapes of their dependencies on n. The calculated ionization rates are compared with the results of our earlier measurements of BBR-induced ionization rates of Na nS and nD Rydberg states with n=8-20 at 300 K. A good agreement for all states except nS with n>15 is observed. We also present the useful analytical formulae for quick estimation ...

Beterov, I I; Ekers, A; Ryabtsev, I I; Tretyakov, D B

2007-01-01T23:59:59.000Z

353

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

354

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

355

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

356

Low Dose Radiation Research Program: Molecular Mechanisms of  

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

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

357

Low Dose Radiation Research Program: The Progeny of Irradiated Mammary  

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

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

358

European Integrated Project RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiations  

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

Integrated Project RISC-RAD Integrated Project RISC-RAD Radiosensitivity of Individuals and Susceptibility to Cancer induced by Ionizing Radiations Laure Sabatier 1 , L.H.F Mullenders 2 , Mike Atkinson 3 , Simon Bouffler 4 , Herwig Paretzke 5 1 Laboratory of Radiobiology and Oncology, CEA, 18 route du panorama BP6 92265 Fontenay-aux- Roses, France 2 LUMC, Department of Toxicogenetics, Postal Zone S-4-P, P.O. Box 9600, 2300 RC Leiden, The Netherlands 3 GSF- Institute of Pathology, Ingolstädter Landstrasse 1, 85764 Neuherberg Germany 4 HPA Radiation Protection Division, Centre for Radiation Chemical and Environmental Hazards, Chilton, UK 5 GSF- Institute of Radiation Protection, Ingolstädter Landstrasse 1, Neuherberg, D-85764 Germany In radiological protection, the risks of inducing stochastic health effects (largely cancer) by a

359

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

360

Ionizing Radiation Activates AMP-Activated Kinase (AMPK): A Target for Radiosensitization of Human Cancer Cells  

SciTech Connect

Purpose: Adenosine monophosphate (AMP)-activated kinase (AMPK) is a molecular energy sensor regulated by the tumor suppressor LKB1. Starvation and growth factors activate AMPK through the DNA damage sensor ataxia-telangiectasia mutated (ATM). We explored the regulation of AMPK by ionizing radiation (IR) and its role as a target for radiosensitization of human cancer cells. Methods and Materials: Lung, prostate, and breast cancer cells were treated with IR (2-8 Gy) after incubation with either ATM or AMPK inhibitors or the AMPK activator metformin. Then, cells were subjected to either lysis and immunoblotting, immunofluorescence microscopy, clonogenic survival assays, or cell cycle analysis. Results: IR induced a robust phosphorylation and activation of AMPK in all tumor cells, independent of LKB1. IR activated AMPK first in the nucleus, and this extended later into cytoplasm. The ATM inhibitor KU-55933 blocked IR activation of AMPK. AMPK inhibition with Compound C or anti-AMPK {alpha} subunit small interfering RNA (siRNA) blocked IR induction of the cell cycle regulators p53 and p21{sup waf/cip} as well as the IR-induced G2/M arrest. Compound C caused resistance to IR, increasing the surviving fraction after 2 Gy, but the anti-diabetic drug metformin enhanced IR activation of AMPK and lowered the surviving fraction after 2 Gy further. Conclusions: We provide evidence that IR activates AMPK in human cancer cells in an LKB1-independent manner, leading to induction of p21{sup waf/cip} and regulation of the cell cycle and survival. AMPK appears to (1) participate in an ATM-AMPK-p21{sup waf/cip} pathway, (2) be involved in regulation of the IR-induced G2/M checkpoint, and (3) may be targeted by metformin to enhance IR responses.

Sanli, Toran; Rashid, Ayesha; Liu Caiqiong [Department of Oncology, Juravinski Cancer Center and McMaster University, Hamilton, Ontario (Canada)

2010-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "dose ionizing radiation" 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.


361

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

362

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

363

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

364

An integrated genetics approach to systemic low-dose radiation responses  

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

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

365

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,

366

Regulation Of Nf=kb And Mnsod In Low Dose Radiation Induced Adaptive Protection Of Mouse And Human Skin Cells  

Science Conference Proceedings (OSTI)

A sampling of publications resulting from this grant is provided. One is on the subject of NF-κB-Mediated HER2 Overexpression in Radiation-Adaptive Resistance. Another is on NF-κB-mediated adaptive resistance to ionizing radiation.

Jian Li

2012-11-07T23:59:59.000Z

367

Non-linear DNA damage response to low-dose ionizing radiation...  

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

the spatiotemporal response in ATM- or DNApkcs-deficient cells or as a function of chromatin territory, to extend the work done by the Karpen Lab using the Drosophila model...

368

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

369

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

370

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

371

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

372

IONIZATION CHAMBER  

DOE Patents (OSTI)

This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

Redman, W.C.; Shonka, F.R.

1958-02-18T23:59:59.000Z

373

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

374

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

375

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

376

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

377

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

378

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

379

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

380

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

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381

Scintillator Waveguide For Sensing Radiation  

DOE Patents (OSTI)

The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.

Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)

2003-04-22T23:59:59.000Z

382

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

383

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

384

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

385

POST-TRAUMATIC DEGENERATION AND REGENERATION OF SYNAPSES IN THE ACTION OF IONIZING RADIATION  

SciTech Connect

A study was made of degeneration and regeneration of synapses in the upper cervical ganglion and section of the sympathetic trunk on the neck of cats after total single x ray irradiation in a dose of 30, 100, or 500 r. There was an acceleration of these processes after the action of low doses, and delay after the action of high doses. The synapses first restored undergo considerable structural changes with the lapse of time and become small and delicate. The scar at the site of nerve section considerably diminishes in size after the high doses of x-ray irradiation. (auth)

Babmindra, V.P.

1962-01-01T23:59:59.000Z

386

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.

387

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

388

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

389

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

390

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

391

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

392

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

393

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:

394

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

395

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

396

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

397

Spectral energy distribution of the metagalactic ionizing radiation field from QSO absorption spectra  

E-Print Network (OSTI)

A computational procedure is presented to estimate the spectral shape of the ionizing background between 1 and 10 Ryd by analyzing optically thin absorption systems in the spectra of high redshift quasars. The procedure is based on the response surface methodology from the theory of experimental design. The shape of the recovered UV background at z~3 shows a significant intensity decrease between 3 and 4 Ryd compared to the metagalactic spectrum of Haardt & Madau (1996). This decrease is interpreted as produced by HeII Gunn-Peterson effect. There are no features indicating a contribution from galaxies to the UV background which is therefore dominated by QSOs at z~3.

I. I. Agafonova; M. Centurion; S. A. Levshakov; P. Molaro

2005-06-07T23:59:59.000Z

398

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

399

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

400

Ionization chamber  

DOE Patents (OSTI)

An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

Walenta, Albert H. (Port Jefferson Station, NY)

1981-01-01T23:59:59.000Z

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401

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

402

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

403

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

404

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

405

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

406

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

407

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

408

Ionizing radiation risks to Satellite Power Systems (SPS) workers in space  

DOE Green Energy (OSTI)

A reference Satellite Power System (SPS) has been designed by NASA and its contractors for the purposes of evaluating the concept and carrying out assessments of the various consequences of development, including those on the health of the space workers. The Department of Energy has responsibility for directing various assessments. Present planning calls for the SPS workers to move from Earth to a low earth orbit (LEO) at an altitude of 500 kilometers; to travel by a transfer ellipse (TE) trajectory to a geosynchronous orbit (GEO) at an altitude of 36,000 kilometers; and to remain in GEO orbit for about 90 percent of the total time aloft. The radiation risks to the health of workers who will construct and maintain solar power satellites in the space environment are studied. The charge to the committee was: (a) to evaluate the radiation environment estimated for the Reference System which could represent a hazard; (b) to assess the possible somatic and genetic radiation hazards; and (c) to estimate the risks to the health of SPS workers due to space radiation exposure, and to make recommendations based on these conclusions. Details are presented. (WHK)

Not Available

1980-12-01T23:59:59.000Z

409

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

410

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

411

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

412

A molecular dynamics simulation of DNA damage induction by ionizing radiation  

E-Print Network (OSTI)

We present a multi-scale simulation of early stage of DNA damages by the indirect action of hydroxyl ($^\\bullet$OH) free radicals generated by electrons and protons. The computational method comprises of interfacing the Geant4-DNA Monte Carlo with the ReaxFF molecular dynamics software. A clustering method was employed to map the coordinates of $^\\bullet$OH-radicals extracted from the ionization track-structures onto nano-meter simulation voxels filled with DNA and water molecules. The molecular dynamics simulation provides the time evolution and chemical reactions in individual simulation voxels as well as the energy-landscape accounted for the DNA-$^\\bullet$OH chemical reaction that is essential for the first principle enumeration of hydrogen abstractions, chemical bond breaks, and DNA-lesions induced by collection of ions in clusters less than the critical dimension which is approximately 2-3 \\AA. We show that the formation of broken bonds leads to DNA base and backbone damages that collectively propagate ...

Abolfath, Ramin M; Chen, Zhe J; Nath, Ravinder

2013-01-01T23:59:59.000Z

413

Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells  

SciTech Connect

Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity.

Wang, Daojing; Jang, Deok-Jin

2009-08-21T23:59:59.000Z

414

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

415

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

416

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

417

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

418

Reduction of Carbon Dioxide inAqueous Solutions by IonizingRadiation  

DOE Green Energy (OSTI)

The question of the conditions under which living matter originated on the surface of the earth is still a subject limited largely to speculation. The speculation has a greater chance of approaching the truth insofar as it includes and is based upon the ever wider variety of established scientific fact. One of the purposes of the herein reported observation was to add another fact to the ever increasing information which might have any bearing upon this most interesting question. It is not our purpose in the present communication to discuss the various proposals or the arguments which have been adduced for and against them. One of the most popular current conceptions is that life originated in an organic milieu on the surface of the earth, (1,2,3,4,5). The problem to which we are addressed is the origin of that organic milieu in the absence of any life. It appeared to us that one source, if not the only source, of reduced carbon compounds in complex arrangements might be the interaction of various high energy radiations with aqueous solutions of inorganic materials, particularly carbon dioxide, and nitrogenous compounds such as ammonia and nitrogen, since it appears that these compounds were the commoner forms in which the essential elements found themselves on the primordial earth. While it has long been known that high energy radiations can cause organic decomposition and oxidation, it seemed useful to us to demonstrate that conditions could be found in which high energy radiations could induce the reduction with water of carbon dioxide and the ultimate creation of polyatomic molecules (other than simple polymerization of monomers) of carbon, oxygen, hydrogen and nitrogen.

Garrison, W.M.; Morrison, D.C.; Hamilton, J.G.; Benson, A.A.; Calvin, M.

1951-03-13T23:59:59.000Z

419

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

420

Review Article: Physics and Monte Carlo Techniques as Relevant to Cryogenic, Phonon and Ionization Readout of CDMS Radiation-Detectors  

E-Print Network (OSTI)

This review discusses detector physics and Monte Carlo techniques for cryogenic, radiation detectors that utilize combined phonon and ionization readout. A general review of cryogenic phonon and charge transport is provided along with specific details of the Cryogenic Dark Matter Search detector instrumentation. In particular this review covers quasidiffusive phonon transport, which includes phonon focusing, anharmonic decay and isotope scattering. The interaction of phonons in the detector surface is discussed along with the downconversion of phonons in superconducting films. The charge transport physics include a mass tensor which results from the crystal band structure and is modeled with a Herring Vogt transformation. Charge scattering processes involve the creation of Neganov-Luke phonons. Transition-edge-sensor (TES) simulations include a full electric circuit description and all thermal processes including Joule heating, cooling to the substrate and thermal diffusion within the TES, the latter of which is necessary to model normal-superconducting phase separation. Relevant numerical constants are provided for these physical processes in germanium, silicon, aluminum and tungsten. Random number sampling methods including inverse cumulative distribution function (CDF) and rejection techniques are reviewed. To improve the efficiency of charge transport modeling, an additional second order inverse CDF method is developed here along with an efficient barycentric coordinate sampling method of electric fields. Results are provided in a manner that is convenient for use in Monte Carlo and references are provided for validation of these models.

S. W. Leman

2011-09-06T23:59:59.000Z

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421

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

422

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

423

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

424

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

425

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

426

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.

427

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

428

Radiation Physics Division  

Science Conference Proceedings (OSTI)

... The Radiation Physics Division, part of the Physical Measurement Laboratory ... the measurement standards for ionizing radiations and radioactivity ...

2013-09-05T23:59:59.000Z

429

THE BEIR-III REPORT AND THE HEALTH EFFECTS OF LOW-LEVEL RADIATION  

E-Print Network (OSTI)

Protection Against Ionizing Radiation from External Sources,Protection Against Ionizing Radiation from External Sources:induction by ionizing radiation. Brit. J. Radiol. 51: 401-

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

430

IN-SITU PROBING OF RADIATION-INDUCED PROCESSING OF ORGANICS IN ASTROPHYSICAL ICE ANALOGS-NOVEL LASER DESORPTION LASER IONIZATION TIME-OF-FLIGHT MASS SPECTROSCOPIC STUDIES  

Science Conference Proceedings (OSTI)

Understanding the evolution of organic molecules in ice grains in the interstellar medium (ISM) under cosmic rays, stellar radiation, and local electrons and ions is critical to our understanding of the connection between ISM and solar systems. Our study is aimed at reaching this goal of looking directly into radiation-induced processing in these ice grains. We developed a two-color laser-desorption laser-ionization time-of-flight mass spectroscopic method (2C-MALDI-TOF), similar to matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) mass spectroscopy. Results presented here with polycyclic aromatic hydrocarbon (PAH) probe molecules embedded in water-ice at 5 K show for the first time that hydrogenation and oxygenation are the primary chemical reactions that occur in astrophysical ice analogs when subjected to Ly{alpha} radiation. We found that hydrogenation can occur over several unsaturated bonds and the product distribution corresponds to their stabilities. Multiple hydrogenation efficiency is found to be higher at higher temperatures (100 K) compared to 5 K-close to the interstellar ice temperatures. Hydroxylation is shown to have similar efficiencies at 5 K or 100 K, indicating that addition of O atoms or OH radicals to pre-ionized PAHs is a barrierless process. These studies-the first glimpses into interstellar ice chemistry through analog studies-show that once accreted onto ice grains PAHs lose their PAH spectroscopic signatures through radiation chemistry, which could be one of the reason for the lack of PAH detection in interstellar ice grains, particularly the outer regions of cold, dense clouds or the upper molecular layers of protoplanetary disks.

Gudipati, Murthy S.; Yang Rui, E-mail: gudipati@jpl.nasa.gov, E-mail: ryang73@ustc.edu [University of Maryland (United States)

2012-09-01T23:59:59.000Z

431

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

432

IONIZING RADIATION DOSIMETRY  

E-Print Network (OSTI)

registered certification marks of the National Institute of Standards and Technology and the federal government, who retain exclusive rights to control the use thereof. Permission to use the term and/or logo is granted to NVLAP-accredited laboratories for the limited purposes of announcing their accredited status, and for use on reports that describe only testing and calibration within the scope of accreditation. NIST reserves the right to control the quality of the use of the term NVLAP and of the NVLAP logo. Contents Contents.......................................................................................................................................................iii Foreword.......................................................................................................................................................v

Betty Ann Torres; Carlos M. Gutierrez

2005-01-01T23:59:59.000Z

433

Ionizing Radiation Detector  

Science Conference Proceedings (OSTI)

A CdZnTe (CZT) crystal provided with a native CdO dielectric coating to reduce surface leakage currents and thereby, improve the resolution of instruments incorporating detectors using CZT crystals is disclosed. A two step process is provided for forming the dielectric coating which includes etching the surface of a CZT crystal with a solution of the conventional bromine/methanol etch treatment, and passivating the CZT crystal surface with a solution of 10 w/o NH.sub.4 F and 10 w/o H.sub.2 O.sub.2 in water after attaching electrical contacts to the crystal surface.

Wright, Gomez W. (Nashville, TN); James, Ralph B. (Livermore, CA); Burger, Arnold (Nashville, TN); Chinn, Douglas A. (Livermore, CA)

2003-11-18T23:59:59.000Z

434

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

435

AREA RADIATION MONITOR  

DOE Patents (OSTI)

S>An improved area radiation dose monitor is designed which is adapted to compensate continuously for background radiation below a threshold dose rate and to give warning when the dose integral of the dose rate of an above-threshold radiation excursion exceeds a selected value. This is accomplished by providing means for continuously charging an ionization chamber. The chamber provides a first current proportional to the incident radiation dose rate. Means are provided for generating a second current including means for nulling out the first current with the second current at all values of the first current corresponding to dose rates below a selected threshold dose rate value. The second current has a maximum value corresponding to that of the first current at the threshold dose rate. The excess of the first current over the second current, which occurs above the threshold, is integrated and an alarm is given at a selected integrated value of the excess corresponding to a selected radiation dose. (AEC)

Manning, F.W.; Groothuis, S.E.; Lykins, J.H.; Papke, D.M.

1962-06-12T23:59:59.000Z

436

Perspectives of Decision-Making and Estimation of Risk in Populations Exposed to Low Levels of Ionizing Radiations  

E-Print Network (OSTI)

exposure to radioactive fallout in radiation-associatedheight of the radioactive fallout deliberations in the early

Fabrikant, J.I.

2010-01-01T23:59:59.000Z

437

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

438

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