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Biomedical subjects

O T Bailey

Publications and source records attributed to O T Bailey.

At least 19 recordsLinked to original sources

Falcine chondrosarcoma: case report and literature review.

We present a case of falcine chondrosarcoma in a 58-year-old man. Only a few other examples of chondrosarcomas in this location and a total of approximately 50 intracranial cases have been reported. Because its rarity prevents any group of neurosurgeons from collecting a large experience in managing this tumor, we reviewed descriptions of previous cases to determine the natural history of intracranial chondrosarcomas. The distinguishing features of this rare tumor are compared with previous examples of intracranial tumors derived from cartilage and more common tumors in the parasagittal region, such as meningioma.

Chondrosarcoma↗

Intramedullary cystic teratoid tumor of the cervical spinal cord in association with a teratoma of the ovary.

A 15-year-old black female student came to the hospital because of disturbance of her gait. On examination, there was a dermal sinus in the skin overlying the spine of the seventh cervical vertebra, and myelography with computed tomography scan demonstrated a block to the flow of metrizamide contrast material at T-5 with cephalad extension of an intradural cystic lesion to the C-5 level. An x-ray examination of the abdomen at the time demonstrated a tooth-shaped radiodensity in the left hypogastrium. On exploration of the spine via C5-T5 laminectomy an intramedullary cystic teratoid tumor was found which was partially excised. At later exploration of the abdomen, a teratoma of the left ovary was removed. The pathology and natural history of teratomas and teratoid tumors is discussed along with surgical management of these tumors.

Adolescent↗

Excision of a large pineal region hemangiopericytoma (angioblastic meningioma, hemangiopericytoma type).

A large hemangiopericytoma was located posterocentrally. The patient presented with headaches and papilledema. Surgical management consisted of total gross excision by a combined right occipital transtentorial and right occipitoparietal transfalcine approach under magnification in three stages over a 6-week period. Removal was aided by dilatation of the right temperooccipital horn ("trapped ventricle") and meningioma-like encapsulation allowed separation of the tumor from the brain and surrounding structures after internal debulking of the tumor. Subsequent peritoneal shunting of the trapped ventricular horn and 5000 rads of radiotherapy were given to the patient. She remains well with an inferior quadrantanopsia on the left side more than 1 year after treatment. Meningiomas of the pineal region, the relationship of meningioma to hemangiopericytoma and malignant mesenchymal tumors (sarcomas) are considered in reference to presumed cells of origin.

Adult↗

Mixed malignant mesenchymal tumor of the cerebellar vermis.

In an example of mixed malignant mesenchymal tumor of the cerebellar vermis, striking osteoblastic differentiation was present along with extensive intradural spinal invasion. The CNS sarcomas and their variants are discussed as well as the extraskeletal osteosarcomas. Comparison is made to the teratoid tumors and other mixed and unusual posterior fossa tumor elements, and the capability of midline posterior fossa tissues for multipotential differentiation is considered.

Cerebellar Neoplasms↗

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↗

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: II. Characteristics and tolerances of the pocket mouse and incidence of disease.

Pocket mice are facultative homoiotherms with the ability to drop their metabolic rate dramatically while at rest or in response to environmental stresses. Under these conditions, they characteristically enter a state of prolonged torpor. These animals require no drinking water and they can live in darkness for many months without apparent ill effect. They tolerate a wide range of ambient temperature, ralative humidity, and oxygen pressure and have survied without food for a mean of 14 d at an ambient temperature of 20 degrees C (68 degrees F). Studies carried out on the pocket mouse colony used for the Apollo XVII flight revealed, in the animals tested, no serological evidence of viral disease, no pathogenic enterobacteria or respiratory Mycoplasma on culture, a 25% incidence of sarcosporidiosis, and a 2% incidence of chronic meningitis or meningoencephalitis. The conclusion reached is that the pocket mouse is a highly adaptive animal and very well suited for space flight.

Adaptation, Physiological↗

The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: appendix III. evaluation of viscera and other tissues.

Histopathological findings in the lungs, livers, bone marrows, small intestines, gonads, kidneys, and other tissues of the four pocket mice (Perognathus longimembris) that survived the Apollo XVII flight were evaluated in the light of their immediate environment and as targest of HZE cosmic ray particles. Results of this study failed to disclose changes that could be ascribed to the HZE particle radiation. Decreased numbers of erythropoietic cells in the bone marrow of the flight mice were probably related to the increased oxygen pressure. The small intestine showed no changes. Ovaries and tests appeared normal. Two of the three surviving male flight mice displayed early stages of spermatogenesis, just as ground-based controls did at the same season. Abnormalities were also not found in the thyroid, parathyroids, adrenals, or kidneys. The status of the juxtaglomerular apparatus could not be evaluated. The lungs exhibited nonspecific slight rections. A variety of incidental lesions were noted in the livers of both the flight mice and their controls. The heart muscle showed nothing that could be regarded as pathological. Sections of skeletal muscle examined were free from significant change.

Adrenal Cortex↗

James W. Kernohan.

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Awards and Prizes↗

Rathke's cleft cyst.

A 29 year old female with a chiasmal syndrome secondary to a Rathke's cleft cyst is described. The histology and pathogenesis of these rare cysts are discussed, contrasting them with other hypophysial cysts.

Adult↗