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Blood changes in humans following total body irradiation

Description: A major problem encountered in the Manhattan Project was the protection of workers against damage resulting from acute or chronic exposure to external radiation. The problem of how to detect evidence of damage following exposure to total body radiation led to this study. These studies were conducted between January, 1942 and November, 1945. Three groups of persons were employed in this study. The first group of eight individuals harboring incurable neoplasms which was not extensive enough to influence general health, these patients were treated with 400 KV x-radiation while sitting in a wooden chair, doses were 27, 60, and 120r. Three persons having generalized illnesses chronic in nature were given total body radiation using 200 KV X-rays in multiple exposures totaling 100, 300, and 500r. A third group of normal volunteers from personnel of the Metallurgical Laboratory were treated with 200 KV x-rays in three divided doses totaling 21 r. Changes in peripheral blood in the fourteen individuals is reported. In group 1 the most persistent abnormality noted was a diminution in the number of lymphocytes after completion of the treatment. In group 2 a depression in the lymphocytes was also the most marked single change. In group 3 no alterations in peripheral blood was observed.
Date: June 2, 1947
Creator: Cantril, S.T.; Jacobson, L.O.; Schwartz, S. & Nickson, J.J.
Partner: UNT Libraries Government Documents Department

INTRACELLULAR COPPER ACCUMULATION ENHANCES THE GROWTH OF KINEOCOCCUS RADIOTOLERANS DURING CHRONIC IRRADIATION

Description: The actinobacteria Kineococcus radiotolerans is highly resistant to ionizing radiation, desiccation, and oxidative stress; though the underlying biochemical mechanisms are unknown. The purpose of this study was to explore a possible linkage between the uptake of transition metals and extreme resistance to ionizing radiation and oxidative stress. The effects of 6 different divalent cationic metals on growth were examined in the absence of ionizing radiation. None of the metals tested were stimulatory, though cobalt was inhibitory to growth. In contrast, copper supplementation dramatically increased cell growth during chronic irradiation. K. radiotolerans exhibited specific uptake and intracellular accumulation of copper compared to only a weak response to both iron and manganese supplementation. Copper accumulation sensitized cells to hydrogen peroxide. Acute irradiation induced DNA damage was similar between the copper-loaded culture as the age-synchronized no copper control culture, though low molecular weight DNA was more persistent during post-irradiation recovery in the Cu-loaded culture. Still, the estimated times for genome restoration differed by only 1 hr between treatments. While we cannot discount the possibility that copper fulfills an unexpectedly important biochemical role in a radioactive environment; K. radiotolerans has a high capacity for intracellular copper sequestration, and presumably efficiently coordinated oxidative stress defenses and detoxification systems, which confers cross-protection from the damaging affects ionizing radiation.
Date: July 24, 2007
Creator: Bagwell, C & Charles Milliken, C
Partner: UNT Libraries Government Documents Department

The acute radiation syndrome: A study of ten cases and a review of the problem

Description: In this report ten cases of acute radiation syndrome are described resulting from two accidents occurring at the Los Alamos Scientific Laboratory of unique nature involving fissionable material. These cases are described in considerable detail. The report comprises ten sections. This volume, part II of the report, is comprised of sections entitled: (1) the Biological Basis for the Clinical Response seen in the Acute radiation Syndrome, (2) Clinical Signs and Symptoms, (3) Discussion of Hematological Findings, (4) Chemistry of the Blood and Urine, (5) Discussion of Pathological Findings, and (6) Reconsiderations of the Calculated Radiation Doses in Terms of the Observed Biological Response of the Patients. This report was prepared primarily for the clinician who is interested in radiation injuries and therefore emphasis has been placed on the correlation of clinical and pathological changes with the type of cytogenetic change known to be produced by ionizing radiation.
Date: March 17, 1950
Creator: Hempelmann, L.H. & Lisco, H.
Partner: UNT Libraries Government Documents Department

Twenty-year review of medical findings in a Marshallese population accidentally exposed to radioactive fallout

Description: A summary is presented of results of medical examinations of inhabitants of the Marshall Islands during the 20-year period following the exposure of Rongelap people to radioactive fallout in 1954. The initial effect observed was $beta$ burns of the skin of some individuals. Few significant findings were observed during the subsequent 9-year period, although an increase in miscarriages and stillbirths among the exposed women was noted. In 1963 some thyroid abnormalities and growth retardation of some children were noted. (177 references). (CH)
Date: January 1, 1975
Creator: Conard, R.A.
Partner: UNT Libraries Government Documents Department

Comments on mutagenesis risk estimation

Description: 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 chronic irradiation can be theoretically and accurately predicted from acute irradiation data. Therefore, direct determination of frequencies of transmitted mutations in mammals continues to be important for risk estimation, and the specific-locus method in mice is shown to be not as expensive as is commonly supposed for many of the chemical testing requirements.
Date: January 1, 1976
Creator: Russell, W.L.
Partner: UNT Libraries Government Documents Department

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

Description: 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. After this, there were no obvious deleterious effects upon the survival and viability of the fish, although irradiated fish weighed less at the termination of the experiment.
Date: May 1, 1979
Creator: Woodhead, A.D. & Setlow, R.B.
Partner: UNT Libraries Government Documents Department

Chemical toxicity of uranium hexafluoride compared to acute effects of radiation

Description: 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 concentration of 25 mg/m{sup 3} for 30 minutes is roughly comparable because there would be no significant nonstochastic effects. For times t other than 30 minutes, the concentration C of hydrogen fluoride considered to have the same effect can be calculated using a quadratic equation: C = 25 mg/m{sup 3} (30 min/t). The purpose of these analyses is to provide information for developing design and siting guideline based on chemical toxicity for enrichment plants using uranium hexafluoride. These guidelines are to be similar, in terms of stochastic health effects, to criteria in NRC regulations of nuclear power plants, which are based on radiation doses. 26 refs., 1 fig., 5 tabs.
Date: February 1, 1991
Creator: McGuire, S.A.
Partner: UNT Libraries Government Documents Department

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

Description: 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.
Partner: UNT Libraries Government Documents Department

Late effects of whole brain irradiation within the therapeutic range

Description: 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 weeks that included confluent areas of necrosis in gray and white matter. Brain loss resulted in ventricular dilatation. Gliomas appeared in two out of three monkeys at or beyond 52 weeks. Exposure to 2000 rads caused such a wide scatter of focal areas of necrosis, including those in the brain stem, that survival beyond 20 to 26 weeks was not possible. All showed enlarged ventricular systems. Whole brain exposure, 200 rads a day, five days a week, for a course of 4000 rads, at puberty, resulted in no delayed effects. Whole brain exposure to 6000 rads in a six weeks course, in the adult, produced less effects than the same dose at puberty. The onset of the scattered necrotic lesions was later than expected, appearing in one out of three animals at 33 weeks, two out of three animals at 52 weeks, and two out of three at 104 weeks. The lesions at 104 weeks were predominantly mineralized, but were accompanied by a greater extent of telangiectasia than seen in the pubescent monkeys.
Date: January 1, 1978
Creator: Caveness, W. F. & Carsten, A. L.
Partner: UNT Libraries Government Documents Department