Biomedical subjects

T Samorajski

Publications and source records attributed to T Samorajski.

At least 55 records · Page 3Linked to original sources

PubMed1975

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: VI. launch, flight, and recovery.

The final phase to fly five pocket mice in the Apollo XVII command module was carried out at the NASA Kennedy Space Center. Upon completion of the 13-d space flight, the package was removed from the spacecraft and, after having been purged with an oxygen-helium gas mixture, was flown to American Samo. Four of the five mice were recovered alive from the package. Analysis of the mouse that died during the flight revealed several factors that could have contributed to its death, the chief of which was massive hemorrhage in its middle ear cavities.

Animals↗

PubMed1975

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: IX Results of examination of the nasal mucosa.

The olfactory epithelium, but not the nasal respiratory epithelium, of the four pocket mice (Perognathus longimembris) that survived their flight on Apollo XVII showed both diffuse alterations and numerous disseminated focal lesions. The olfactory mucosa of the mouse that died during flight was also affected, but to a minor degree insofar as could be determined. All this was in contrast to the normal appearance of the olfactory mucosa of the numerous control animals. A number of possible causes were considered: systemic or regional infection; inhaled particulate material (seed dust); by-products from the KO2 bed in aerosol or particulate form; gas contaminants originating in the flight package; volatile substances from the dead mouse; weightlessness; and cosmic ray particle radiation. Where feasible, studies were conducted in an effort to rule in or rule out some of these potentially causative factors. No definitive conclusions were reached as to the cause of the lesions in the flight mice.

Aerosols↗

PubMed1975

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: X. Results of ear examination.

In the five pocket mice flown on Apollo XVII, no evidence was found that the inner ear had been damaged, though poor fixation precluded detailed study. On the other hand, the middle ear cavity was involved in all the mice, hemorrhage having occurrred in response to excursions in pressure within the canister that housed the mice during their flight. The same occurred in flight control mice which had been subjected to pressure excursions of much the same magnitude. A greater degree of exudation into air cells and greater leukotaxis were noted in the flight animals than in the control animals. There was no increase in leukocyte population along the paths of the 23 cosmic ray particles registered in the subscalp dosimeters that traversed the middle ear cavities of the flight mice. The increased exudation and the greater response by leukocytes in the flight mice may have been causally related to the lesions found in their olfactory mucosa but there were no data in support of this possibility.

Animals↗

PubMed1975

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: XII. Results of examination of the calvarium, brain, and meninges.

Tissue reactions were found around the monitor (dosimeter) assemblies that had been implanted beneath the scalp of the five pocket mice that flew on Apollo XVII. Mitosis in the dentate gyrus of the hippocampal formation was considerably reduced in comparison with that in control animals. Otherwise the brain tissue as well as the menings in the flight animals appeared unaltered. Since the animals were exposed primarily to high Z-high energy (HZE) cosmic ray particles at the lower end of the high LET spectrum, the lack of changes in the brain cannot be taken as evidence that the brain will suffer no damage from the heavier HZE particles on prolonged manned missions.

Animals↗

PubMed1975

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: appendix I. Condition of flight animals on recovery; food intake; observations on hypothalamus, pituitary, and adrenal glands.

The rationale for studying certain hypothalamic nuclei and the pituitary and adrenal glands of the pocket mice that flew on Apollo XVII was the need to evaluate the effects of the potentially severe stress on these animals in the foreign environment of flight canister, weightlessness, increased G forces, and other unnatural conditions. Decrease in body weight and variability of food intake were significant among the four flight animals that were recovered alive. The mean nuclear diameter of neurons in the arcuate and ventromedial hypothalamic nuclei did not differ significantly from the values obtained in the control animals. On the other hand, the mean nuclear diameter of neurons in the supraoptic nucleus of the flight mice was significantly greater than in the control groups. Comparisons of the adeno- and neuropypophysis revealed no significant differences among the three groups. Insofar as they were studied, the adrenals were similar in all groups.

Adaptation, Physiological↗

PubMed1974