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Biomedical subjects

W C Davis

Publications and source records attributed to W C Davis.

At least 271 records · Page 15Linked to original sources
PubMed1975

Effect of cyclophosphamide on the response of chickens to a virulent strain of Marek's disease virus.

The effect of cyclophosphamide on the pathogenesis of Marek's disease was examined in a line of chickens which is relatively resistant to Marek's disease. The injection of cyclophosphamide into newly hatched chickens delayed and reduced viremia and also reduced the development of Marek's disease lesions until 2 weeks after exposure to Marek's disease virus. The data indicate that a population of T cells susceptible to infection with virus and possibly viral transformation is affected by cyclophosphamide.

Animals↗
PubMed1975

Surgical anatomy of the mesocaval shunt.

Having encountered wide variations in the surgical trunk of the superior mesenteric vein and its arterial relationships during the performance of mesocaval shunts, we believed it would be rewarding to evaluate this vessel in a series of 36 cadavers. In two of these 36 instances, we determined that the anatomic findings precluded the performance of a mesocaval shunt. In ten other instances, even though a shunt could be performed, a knowledge of these variations could prevent operative complications. The most common variation was a bifurcation of the superior mesenteric vein at or proximal to the site of the surgical trunk. Another variation which could cause operative difficulties was unusual positions of the superior mesenteric artery and its major branches in relation to the vein at the level of the surgical trunk. A knowledge of these variations in the surgical anatomy of the superior mesenteric vein should make mesocaval shunts easier and safer to perform.

Humans↗
PubMed1975

Ultrastructural features of viral leukoencephalomyelitis of goats.

Ultrastructural studies were made of the central nervous system of three goats during the early stages of viral leukoencephalomyelitis of goats and of one goat 3 years after onset of the disease. In both early and late lesions, the following features were recognized: loss of myelin from normal axons, separation of the myelin sheath from the axon by cell processes, pronounced astrocytosis with numerous cell processes packed with heavy fibrils, paucity of oligodendrocytes, normal capillaries, and normal cellular elements in the adjacent gray matter. Early lesions also had many cells of the lymphoid series infiltrating perivascular spaces, within lesions, and, particularly, along axons undergoing demyelination. Although viral particles were extensively sought, only one suspect structure, with a tubular nucleocapsid-like configuration, was seen. Individual tubules of this particle measured 22 nm. in diameter. The ultrastructural features of demyelination in viral leukoencephalomyelitis of goats were compared with those described for demyelination that occurs in multiple sclerosis, experimental allergic encephalomyelitis, canine distemper encephalomyelitis, and that produced by diphtheria toxin.

Animals↗
PubMed1975

Immunoglobulins and anti-Marek's disease virus antibody synthesis in chickens after passive immunization with immunoglobulin Y anti-Marek's disease virus antibody.

The effect of passive immunization with immunoglobulin Y (IgY) antibody against Marek's disease virus (MDV) was examined in MDV-susceptible chickens. The production of IgY, immunoglobulin M, and probably also immunoglobulin A was depressed in passively immunized chickens when compared with that in MDV-exposed chickens which had not been given IgY anti-MDV antibody. In passively immunized chickens, the synthesis of immunoglobulin M and IgY anti-MDV antibodies in response to MDV infection also was delayed as determined by agar gel precipitin and indirect fluorescence antibody tests.

Animals↗
PubMed1974

Physiological and Cytological Similarities between Disease Resistance and Cellular Incompatibility Responses.

Excised pea pods responded similarly to both the invasion of plant pathogenic fungi and the presence of bean tissue, bean pollen, and mouse tumor cells by synthesizing pisatin and by developing a characteristic yellow-green fluorescence. Both responses were dependent on RNA and protein synthesis. Conversely, the foreign pollen and incompatible fungi were sensitive to the pea pod tissue and were subject to abnormal development.The induction of pisatin and the yellow-green fluorescence development were mediated by multiple compounds of varying sizes released by fungi or mouse tumor cells. The incompatibility between a bean pathogen, Fusarium solani f. sp. phaseoli, and pea pod tissue was hypothesized to occur as a result of the cross contamination of such inducing compounds.

Journal Article↗
PubMed1974

Leukocyte dysfunction in the bovine homologue of the Chediak-Higashi syndrome of humans.

The increased susceptibility to pyogenic infections noted in cattle with the Chediak-Higashi syndrome trait has been related to an impairment of leukocyte function at the cellular level. Investigations of the relationship of abnormal granule formation to increased susceptibility to infection, conducted with cell suspensions containing high concentrations of polymorphonuclear leukocytes, revealed a bactericidal defect that was associated with abnormal intracellular killing and not due to defective particle ingestion. The in vitro bactericidal defect was associated with a metabolic anomaly in the hexose monophosphate shunt, but not with an alteration in the capacity to reduce nitroblue tetrazolium dye. Ultrastructural histochemical studies of phagocytosis and phagolysosome formation in polymorphonuclear leukocytes suggest that the impairment in bactericidal capacity is correlated also with either a delay or failure of primary granules to degranulate.

Animals↗