Abstract
{sup 85}Sr sources are installed in the initial US biosatellites to provide calculable dose levels during three-day orbital space flights. Such protracted exposures are longer than those used customarily in insect radiobiology and shorter than those of ecological studies. This paper concerns results from the ground controls of ill-fated US Biosatellite A and compares them with results from other dose rates and types of radiation. Males are packaged separately and used for mutational studies to be reported elsewhere. To compare the vulnerability of cell types in the ovariole sequence, nearly 1000 virgin females from a vigorous out- cross are used, half for ground controls and half for the satellite launched. Samples of 20-25 wasps are packed in each of two screw-capped capsules inserted into housings in plastic modules which also incorporate thermisters and radiodosimeters. These packages are fixed in shielded positions as well as in places which receive one of four levels of gamma rays from the {sup 85}Sr source. Each treatment thus consists of 40-50 virgins; a similar number receives a sensitizing preflight exposure to 2000 R of X-rays. After the flight period daily egg production is scored to detect resorption following gross chromosomal damage, embryonic deaths to reveal
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Grosch, D. S.
[1]
- Genetics Department, North Carolina State University, Raleigh, NC (United States)
Citation Formats
Grosch, D. S.
Reproductive Performance of Female Braconids Compared after (A) Brief and (B) Protracted Exposures to Ionizing Radiations.
IAEA: N. p.,
1968.
Web.
Grosch, D. S.
Reproductive Performance of Female Braconids Compared after (A) Brief and (B) Protracted Exposures to Ionizing Radiations.
IAEA.
Grosch, D. S.
1968.
"Reproductive Performance of Female Braconids Compared after (A) Brief and (B) Protracted Exposures to Ionizing Radiations."
IAEA.
@misc{etde_22106399,
title = {Reproductive Performance of Female Braconids Compared after (A) Brief and (B) Protracted Exposures to Ionizing Radiations}
author = {Grosch, D. S.}
abstractNote = {{sup 85}Sr sources are installed in the initial US biosatellites to provide calculable dose levels during three-day orbital space flights. Such protracted exposures are longer than those used customarily in insect radiobiology and shorter than those of ecological studies. This paper concerns results from the ground controls of ill-fated US Biosatellite A and compares them with results from other dose rates and types of radiation. Males are packaged separately and used for mutational studies to be reported elsewhere. To compare the vulnerability of cell types in the ovariole sequence, nearly 1000 virgin females from a vigorous out- cross are used, half for ground controls and half for the satellite launched. Samples of 20-25 wasps are packed in each of two screw-capped capsules inserted into housings in plastic modules which also incorporate thermisters and radiodosimeters. These packages are fixed in shielded positions as well as in places which receive one of four levels of gamma rays from the {sup 85}Sr source. Each treatment thus consists of 40-50 virgins; a similar number receives a sensitizing preflight exposure to 2000 R of X-rays. After the flight period daily egg production is scored to detect resorption following gross chromosomal damage, embryonic deaths to reveal more subtle damage, and maternal life span as a measure of somatic fitness. In most insects bundles of numerous ovarioles confound interpretation relating cell status during exposure to eggs deposited subsequently. Habrobracon's four synchronized ovarioles provide a uniquely suitable system for studying radiosensitivity of a sequence complete from specialized oocytes through oocyte- trophocyte units to primitive interphase cells. Following a series of doses, the family of oviposition curves reflects the vulnerability of differentiating units in a valley which deepens and broadens with increased dose. At high dose rates, lowest egg production occurs on day 7. The pattern, well established for X-rays and {sup 32}P {beta}-rays, has now been demonstrated for {gamma}-rays from the Raleigh {sup 60}CO Gammacell and the Woods Hole {sup 137}Cs source, although 1.4 times the X-ray dose is required to produce the same amount of damage. When the gamma exposure was spread over three days the valley did not appear until the eighth day. Females tested simultaneously and treated identically except that their X-ray exposure was brief provided the usual 7th-day low. Previously valley deferment was observed only when studying ingested radioisotopes where a necessary prestarvation obscured the significance. Another unpredicted response to the protracted gamma dose was a control level productivity of eggs derived from exposed oogonia. Recovery mechanisms were evidently able to keep pace with radiation damage. On the other hand, embryonic lethality was related to dose during all periods studied and dose rate was not important except for the most mature ooecytes. As scored by von Borstel categories, stage I deaths decreased and stage III types increased with age of the mothers until the latter predominated. This change is age-related and not dose-dependent. Biochemically, predominance of stage III death can be induced, even in eggs from young mothers, by feeding either RNA or protein inhibitors, but not by interfering with DNA synthesis. We postulate physiological involvement of nurse cells and fat body or their interrelations. Mean life span ranged from 19.52 {+-}1.34 days after 4320 R to 22.35 {+-}0.91 for controls. Biosatellite B, the second effort, was recovered successfully. After two days in orbit the reproductive performance of females differed strikingly from that repeated in ground controls. Most significant was egg deposit in a nearly contourless pattern reminiscent of a compensatory response to mitotic inhibition. (author)}
place = {IAEA}
year = {1968}
month = {Jun}
}
title = {Reproductive Performance of Female Braconids Compared after (A) Brief and (B) Protracted Exposures to Ionizing Radiations}
author = {Grosch, D. S.}
abstractNote = {{sup 85}Sr sources are installed in the initial US biosatellites to provide calculable dose levels during three-day orbital space flights. Such protracted exposures are longer than those used customarily in insect radiobiology and shorter than those of ecological studies. This paper concerns results from the ground controls of ill-fated US Biosatellite A and compares them with results from other dose rates and types of radiation. Males are packaged separately and used for mutational studies to be reported elsewhere. To compare the vulnerability of cell types in the ovariole sequence, nearly 1000 virgin females from a vigorous out- cross are used, half for ground controls and half for the satellite launched. Samples of 20-25 wasps are packed in each of two screw-capped capsules inserted into housings in plastic modules which also incorporate thermisters and radiodosimeters. These packages are fixed in shielded positions as well as in places which receive one of four levels of gamma rays from the {sup 85}Sr source. Each treatment thus consists of 40-50 virgins; a similar number receives a sensitizing preflight exposure to 2000 R of X-rays. After the flight period daily egg production is scored to detect resorption following gross chromosomal damage, embryonic deaths to reveal more subtle damage, and maternal life span as a measure of somatic fitness. In most insects bundles of numerous ovarioles confound interpretation relating cell status during exposure to eggs deposited subsequently. Habrobracon's four synchronized ovarioles provide a uniquely suitable system for studying radiosensitivity of a sequence complete from specialized oocytes through oocyte- trophocyte units to primitive interphase cells. Following a series of doses, the family of oviposition curves reflects the vulnerability of differentiating units in a valley which deepens and broadens with increased dose. At high dose rates, lowest egg production occurs on day 7. The pattern, well established for X-rays and {sup 32}P {beta}-rays, has now been demonstrated for {gamma}-rays from the Raleigh {sup 60}CO Gammacell and the Woods Hole {sup 137}Cs source, although 1.4 times the X-ray dose is required to produce the same amount of damage. When the gamma exposure was spread over three days the valley did not appear until the eighth day. Females tested simultaneously and treated identically except that their X-ray exposure was brief provided the usual 7th-day low. Previously valley deferment was observed only when studying ingested radioisotopes where a necessary prestarvation obscured the significance. Another unpredicted response to the protracted gamma dose was a control level productivity of eggs derived from exposed oogonia. Recovery mechanisms were evidently able to keep pace with radiation damage. On the other hand, embryonic lethality was related to dose during all periods studied and dose rate was not important except for the most mature ooecytes. As scored by von Borstel categories, stage I deaths decreased and stage III types increased with age of the mothers until the latter predominated. This change is age-related and not dose-dependent. Biochemically, predominance of stage III death can be induced, even in eggs from young mothers, by feeding either RNA or protein inhibitors, but not by interfering with DNA synthesis. We postulate physiological involvement of nurse cells and fat body or their interrelations. Mean life span ranged from 19.52 {+-}1.34 days after 4320 R to 22.35 {+-}0.91 for controls. Biosatellite B, the second effort, was recovered successfully. After two days in orbit the reproductive performance of females differed strikingly from that repeated in ground controls. Most significant was egg deposit in a nearly contourless pattern reminiscent of a compensatory response to mitotic inhibition. (author)}
place = {IAEA}
year = {1968}
month = {Jun}
}