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in subjects: "Acute Irradiation"

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Summary of thyroid findings in Marshallese 22 years after exposure to radioactive fallout

Inhabitants of several atolls in the Marshall Islands were accidently exposed to fallout radiation following a detonation of a high yield thermonuclear device during experiments at Bikini in the Pacific Proving Grounds in March 1954. The most serious acute effects of the exposure were due to penetrating gamma radiation. Contamination of the skin in the Rongelap group resulted in widespread beta burns and epilation. These lesions healed and hair regrew normally within several months. Radiochemic… more

Date: January 1, 1976

Creator: Conard, R A

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Genetic effects of radiation. [Extrapolation of mouse data to man]

Data are reviewed from studies on the genetic effects of x radiation in mice and the extrapolation of the findings for estimating genetic hazards in man is discussed. Data are included on the frequency of mutation induction following acute or chronic irradiation of male or female mice at various doses and dose rates.

Date: January 1, 1976

Creator: Selby, P. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of an Acute Dose of Gamma Radiation Exposure on Stem Diameter Growth, Carbon Gain, and Biomass Partitioning in Helianthus annuus

Nineteen-day-old dwarf sunflower plants (Helianthus annuus, variety NK894) received a variable dose (0-40 Gy) from a cobalt-60 gamma source. A very sensitive stem monitoring device, developed at Battelle's Pacific Northwest Laboratories, Richland, Washington was used to measure real-time changes in stem diameter. Exposure of plants caused a significant reduction in stem growth and root biomass. Doses as low as 5 Gy resulted in a significant increase in leaf density, suggesting that nonreversibl… more

Date: May 25, 1988

Creator: Thiede, M. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Phenomenological models

The biological effects of ionizing radiation exposure are the result of a complex sequence of physical, chemical, biochemical, and physiological interactions. One way to begin a search for an understanding of health effects of radiation is through the development of phenomenological models of the response. Many models have been presented and tested in the slowly evolving process of characterizing cellular response. A range of models covering different endpoints and phenomena has developed in pa… more

Date: September 1, 1990

Creator: Braby, L.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Comparison of late effects of single x-ray exposure, chronic tritiated water ingestion, and chronic cesium-137 gamma exposure in mice

There is concern over the possible late effects resulting from chronic exposure to tritiated water, a primary by-product of power reactors. We are comparing the genetic and somatic effects of tritiated water ingestion to acute x-ray or chronic cesium-137 gamma-ray exposures. Eight week old mice were maintaned on tritiated water in concentrations of 0.3, 1.0, and 3.0 ..mu..Ci/ml. Identical animals received cesium-137 gamma exposures equivalent to that from the tritiated water. At 4 week interval… more

Date: January 1, 1979

Creator: Carsten, A.L. & Cronkite, E.P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mutational repair in mammals and its bearing on risk assessment

Most of the genetic risk from radiation in humans will involve germ cell stages that are of long duration, namely, the spermatogonial stem cells in the male and the oocytes in the female. Mutagenic studies in the mouse that are concerned with risk assessment have, therefore, concentrated on these stages. The first evidence that some repair of mutational damage could occur came from investigations with the specific-locus method in the mouse in which it was shown that when a given dose of radiati… more

Date: January 1, 1977

Creator: Russell, W.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effect of graded doses of ionizing radiation on the human testis. [X rays]

Sixty-seven human subjects with normal testicular function were subjected to acute testicular irradiation in doses ranging from 8R to 600 R. Post irradiation observations included sperm counts and morphology, and radioimmunoassays for levels of reproductive steroids and hormones in urine (later plasma). Preliminary results and irradiation procedures are tabulated. An overview and analysis of results to date is published in a separate communication. (ERB)

Date: January 1, 1974

Creator: Rowley, M J; Leach, D R; Warner, G A & Heller, C G

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Probabilistic methodology for estimating radiation-induced cancer risk

The RICRAC computer code was developed at Oak Ridge National Laboratory to provide a versatile and convenient methodology for radiation risk assessment. The code allows as input essentially any dose pattern commonly encountered in risk assessments for either acute or chronic exposures, and it includes consideration of the age structure of the exposed population. Results produced by the analysis include the probability of one or more radiation-induced cancer deaths in a specified population, exp… more

Date: January 1, 1981

Creator: Dunning, D. E. Jr.; Leggett, R. W. & Williams, L. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Near-term and late biological effects of acute and low-dose-rate continuous gamma-ray exposure in dogs and monkeys

Monkeys (Macaca mulatta) and dogs (beagle) were given thirteen 100-rad gamma-ray doses at 28-day intervals. The comparative response (inury and recovery) of the hematopoietic system of the two species was observed at 7-day intervals during the exposure regime. At 84 days after the thirteenth gamma-ray dose, the 1300-rad conditioned and control dogs and monkeys were challenged continuously with gamma rays at 35 r/day until death to determine the amount of radiation-induced injry remaining in con… more

Date: July 1, 1979

Creator: Spalding, J.F. & Holland, L.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Study on the induction of thyroid tumors in rats using x irradiation in conjunction with a goitrogen. [1 methyl--2 mercaptoimidazole (methimazole)]

The influence of acute localized thyroid x irradiation and chronic goitrogen administration, separately or combined, on thyroid tumor formation in mature female rats was studied. In the first experiment, the radiation doses were 0, 80, 160, 320, or 640 rads, and the dosages of goitrogen were 0, 4, or 40 parts per million (ppM) of 1 methyl - 2 mercaptoimidazole (MMI). The incidence of rats with thyroid tumors in any treated group receiving 0 or 4 ppM MMI was not significantly greater than the in… more

Date: January 1, 1979

Creator: Mahler, P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Study of irradiated bone: Part III. /sup 99m/Tc pyrophosphate autoradiographic changes. [X rays; rabbits]

The macroautoradiographic and microautoradiographic localization of /sup 99m/Tc-pyrophosphate (/sup 99m/TcPPi) was studied in x-irradiated bone of rabbits up to one year post-irradiation. In cortical bone, /sup 99m/TcPPi was concentrated on bone surfaces near vasculature. Both forming and resorbing bone surfaces were comparably labeled at 2 hrs post-injection. Uptake on the surface of sites of haversian bone remodeling was observed to be at least part of the increased /sup 99m/TcPPi observed in… more

Date: January 1, 1978

Creator: King, M. A.; Corriveau, O.; Casarett, G. W. & Weber, D. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

The chemical effects from acute exposures to uranium hexafluoride are compared to the nonstochastic effects from acute radiation doses of 25 rems to the whole body and 300 rems to the thyroid. The analysis concludes that an intake of about 10 mg of uranium in soluble form is roughly comparable, in terms of early effects, to an acute whole body dose of 25 rems because both are just below the threshold for significant nonstochastic effects. Similarly, an exposure to hydrogen fluoride at a concent… more

Date: February 1, 1991

Creator: McGuire, S.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Relationship between unscheduled DNA synthesis and mutation induction in male mice

Unscheduled DNA synthesis (UDS) induced in the germ cells of male mice by chemical and physical agents can be studied in vivo by making use of the timing of spermatogenesis and spermiogenesis. In meiotic and post-meiotic germ-cell stages UDS occurs from leptotene through mid-spermatid stages but is not detected in later stages. No consistent correlation has been seen between the occurrence of UDS in the germ cells and reduced dominant-lethal frequencies or reduced specific-locus mutation freque… more

Date: January 1, 1979

Creator: Sega, G. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Response to and recovery from acute sublethal gamma radiation in the Amazon molly, Poecilia formosa

Acute irradiation of the Amazon molly with a sublethal dose of 1,000 rad caused some damage to the intestinal tract and to the haematopoietic system. Histologically, the intestine appeared to have regenerated by the end of a week; damage to the haematopoietic tissue appeared more slowly, but repair was almost complete some two months later. Nevertheless, recovery to the intestine cannot have been entirely completed in seven days, since the fish did not feed well for the following two weeks. Aft… more

Date: May 1, 1979

Creator: Woodhead, A. D. & Setlow, R. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?

Abstract: Two nuclear accidents involving a plutonium sphere just subcritical in size occurred at the Los Alamos Laboratory, LA-1 in 1945 and LA-2 in 1946. Because remote control devices were deemed unreliable at the time, the tamper material (tungsten carbide bricks in LA-1 and beryllium hemispheres in LA-2) was added by hand with the operator standing next to the assembly. In each case the critical size of the assembly was accidentally exceeded and the resultant exponentially increasing chain… more

Date: 1979

Creator: Hempelman, Louis Henry; Lushbaugh, Clarence C. & Voelz, George L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Pathogenic mechanism in lung fibrosis. [Synergistic effects of BHT, O/sub 2/, and x rays in mice]

The purpose of the study was to examine whether an interaction between two agents causing alveolar epithelial damage would produce lung fibrosis. In mouse lung, intraperitoneal injection of the antioxidant butylated hydroxytoluene causes diffuse alveolar type I cell necrosis, followed by proliferation of type II alveolar cells. In animals exposed to 70% O/sub 2/ or 100-200 rad x rays during the phase of type II cell proliferation following BHT, diffuse interstitial lung fibrosis developed withi… more

Date: January 1, 1979

Creator: Witschi, H.; Haschek, W. M.; Meyer, K. R.; Ullrich, R. L. & Dalbey, W. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Genetic effects of low x-ray doses. Progress report, October 1, 1976--September 30, 1977. [In Drosophila]

A linear-quadratic model of dose-kinetics is proposed for x-ray induced recessive lethal mutations in oogonia of Drosophila. From this it should follow that at higher total doses fractionation treatments should give a lower yield of mutations than an equivalent acute exposure. A dose of 6000 R, given acutely and in 3 different fractionation regimes gave results in the expected direction for 2 x 3000 R, and a significant decrease for 3 x 2000 R and for 4 x 1500 R fractionations.

Date: September 1, 1977

Creator: Abrahamson, S. & Meyer, H.U.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Comments on mutagenesis risk estimation

Several hypotheses and concepts have tended to oversimplify the problem of mutagenesis and can be misleading when used for genetic risk estimation. These include: the hypothesis that radiation-induced mutation frequency depends primarily on the DNA content per haploid genome, the extension of this concept to chemical mutagenesis, the view that, since DNA is DNA, mutational effects can be expected to be qualitatively similar in all organisms, the REC unit, and the view that mutation rates from c… more

Date: January 1, 1976

Creator: Russell, W.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Late effects of whole brain irradiation within the therapeutic range

Whole brain exposure with supervoltage x irradiation was carried out in three sets of Macaca mulatta. Two sets of 12 monkeys each, at puberty, received single and fractionated exposures, respectively. One set of 21 monkeys in adulthood received a fractionated exposure. Exposure to 1000 rads in a single dose, at puberty, caused no late effects. Exposure to 1500 rads caused small areas of necrosis in the forebrain white matter at 26 weeks, but a much more extensive involvement at and beyond 52 we… more

Date: January 1, 1978

Creator: Caveness, W. F. & Carsten, A. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department