Lymphatic involution and early mortality in the young chicken produced by 2.2 GeV protons

Young single-comb white Leghorn cockerels were subjected to single acute doses of either 2.2 GeV protons or 250 kVp X-rays. Since young chickens exposed in the lethal range die within 48 hours of exposure, an hourly tabulation of deaths was recorded for this length of time after exposure. Animals which were exposed to sublethal doses were killed five days after exposure and their major lymphatic organs, (thymus, bursa, and spleen), removed and weighed. In the lethal range, animals exposed to 2.2 GeV protons died sooner than those receiving similar doses of X-rays, but total mortality was similar in each case at similar dose levels. The 48 hour LD sub 50 was determined to be 710 rad. Measured five days after exposure, 50% depression ED sub 50 for lymphatic organs occurred as follows: (1) thymus, 350 rad; (2) pursa, 500 rad, and (3) spleen, 450 rad. In all case R.B.E. values were not different from unity

Evaluation of the hazard from exposure to electron irradiation simulating that in the synchronous orbit

The electron spectrum predicted for the synchronous orbit was simulated to determine the effects that might occur to astroscientists exposed to such irradiation while on a prolonged space station mission in that region. Miniature pigs were exposed to monoenergetic and spectral-fractionated irradiations with 0.5 to 2.1 MeV electrons. Clinical and pathological alterations observed in biopsies were correlated with depth-dose pattern and length of post irradiation period up to one year. With monoenergetic electrons, the lowest dose causing a recognizable lesion was 1450 rad and with increasing dose lesions appeared earlier and were more severe. At the highest dose given, 2650 rad, ulceration extending into the dermis was present by twenty one days and required about four months for complete healing. Spectral-fractionated irradiations, in which the total dose range was essentially comparable to that of the monoenergetic series, resulted in very minimal outer dermis edema at 1790 rad and at no dose employed did necrosis of epidermis or ulceration into dermis occur

Prevalence of diabetic and atherosclerotic complications among Mohawk Indians of Kahnawake, PQ.

We surveyed adults with diabetes mellitus and adults without diabetes living in the Mohawk community of Kahnawake, PQ, for clinical characteristics related to vascular disease. People with diabetes were selected from a clinical register; nondiabetic subjects were randomly selected from a community register, with matching for age and sex. The response rates among the two groups were 62% and 39% respectively; groups of 82 and 94 people were obtained. Data were collected by chart review, interview and body measurement. The prevalence rate of ischemic heart disease was 48% for the subjects with diabetes and 22% for those without diabetes. The adjusted odds ratio for development of ischemic heart disease in a person with diabetes was 3.56, for development of cerebrovascular disease 4.57 and for development of peripheral vascular disease 5.51. Logistic regression for macrovascular disease showed that age, sex, smoking, hypertension and obesity could not explain the high rates of complications in the subjects with diabetes. The prevalence rates of ischemic heart disease in adults with and without diabetes are the highest reported in a North American Indian population