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W Zeman

Publications and source records attributed to W Zeman.

At least 37 records · Page 2Linked to original sources

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↗

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↗

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↗

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↗

Persistent infection of BSC-1 cells by defective measles virus derived from subacute sclerosing panencephalitis.

A line of cells (IP-3), persistently infected with defective measles virus, was developed from co-cultures of subacute sclerosing panencephalitis-derived brain cells with monkey kidney cells (BSC-1). The line, carried for more than 45 serial passages, produced neither infectious virus nor hemagglutinin. Cultures consistently displayed a cycling focal cytopathic pattern of infection characterized by formation of syncytia, necrosis, and plaques followed by healing. Fluorescent measles antigen was present in damaged areas only, especially in syncytia. The development of syncytia was suppressed by measles antibody. Syncytia were lysed by antibody plus rabbit complement. A variant noncytopathic subline (IP-3-Ca) was derived from the 16th passage. Infectious virus was not detected. Cells were minimally positive for hemadsorption. Fluorescent measles antigen was present in all cells. Co-cultures of IP-3-Ca cells with normal BSC-1 cells developed massive syncytia and extensive destruction. The IP-3-Ca cells multiplied in the presence of measles antibodies and were destroyed by antibodies plus complement. The possible relevance of these findings to the pathogenesis of subacute sclerosing panencephalitis is discussed.

Adolescent↗

Deficiency of alpha-L-fucosidase.

A new form of alpha-L-fucosidase deficiency has been found in a 20-year-old severely retarded male. Additional signs include angiokeratoma corporis diffusum and anhydrosis. The skin lesion is due to an accumulation of residual bodies, presumably containing oligosaccharides and glycoproteins, in endothelial cells and fibrocytes. The enzyme activity in blood relatives indicates that the disease is inherited as a simple autosomal recessive trait that segregates according to Mendelian principles. Because the enzyme activity in the heterozygotes was consistently below that of normal controls, the carriers of the trait in this family could be ascertained.

Adult↗

Morphologic approaches to the nosology of nervous system defects.

Recent technologic advances demonstrate that the morphologic approach to the nosologic delineation of nervous system disorders is often inadequate. This tenet is exemplified by the hopeless confusion which neuropathology has imparted on the problem of amaurotic familial idiocy. The delineation of nosologic entities involving the nervous system may depart from morphologic studies but requires rigid confirmation by genetic and biochemical observations.

Adult↗