PubMed Health⌕ Search

Biomedical subjects

M Pollard

Publications and source records attributed to M Pollard.

At least 127 records · Page 7Linked to original sources

Inactivation of viruses and bacteria by ozone, with and without sonication.

Selected organisms with public health significance were placed in a reaction chamber for treatment by ozonation, by ozonation and sonication, by sonication, or by sonication during oxygenation. Vesicular stomatitis virus, encephalomyocarditis virus, GDVII virus, Staphylococcus aureus, Pseudomonas fluorescens, Salmonella typhimurium, enteropathogenic Escherichia coli, Vibrio cholerae, and Shigella flexneri were inactivated by treatment with ozone. When microorganisms were suspended in phosphate-buffered saline, they were inactivated rapidly by treatment with ozone. However, microorganisms suspended in secondary effluent from a wastewater treatment plant required longer contact times with ozone for complete inactivation. Simultaneous treatments by ozonation and sonication reduced the contact time for complete inactivation of microorganisms in secondary effluent. Treatment by sonication alone or sonication and oxygenation did not inactivate microorganisms. Therefore, the simultaneous treatment of microorganisms in secondary effluent with ozone and sonication resulted in a synergistic effect.

Animals↗

Effects of cholestyramine on 1,2-dimethylhydrazine-induced enteric carcinoma in germfree rats.

Oral administration of 1,2-dimethylhydrazine (DMH) induced intestinal neoplasms in germfree rats. A supplement of 2% cholestyramine resin in the diet increased the frequency of DMH-induced intestinal tumors and accelerated malignant transformation. Bile acids in the cecal content were determined with and without cholestyramine in order to obtain a correlation between the bile acid metabolism and the enteric carcinogenesis.

Adenocarcinoma↗

Transplantable metastasizing prostate adenocarcinomas in rats.

Three spontaneous prostate adenocarcinomas from aged, randombred, germfree Lobund Wistar rats were transplanted, without change, through several series of conventional Lobund Wistar rats. One tumor type differed histologically from the other two tumor types. Rats with subcutaneously transplanted tumors developed metastatic tumors in the lymph nodes and lungs. No microbial agent was detected in the tumor cells.

Adenocarcinoma↗

Responses of lymphocytic choriomeningitis carrier mice to X-ray-induced lymphoma.

The data presented in this paper define the interrelationship between two endogenous diseases in the same host. The Haas strain of germfree mice with congenitally acquired persistent lymphocytic choriomeningitis (LCM) virus infection developed the X-ray-induced lymphatic leukemia independent of LCM viremia. The immunoproliferative LCM-related lesions appeared after age 7 months, and the radiogenic lymphatic leukemia appeared earlier or during the same age period. Both diseases evolved with distinctive lesions at the appropriate time, with no evidence of interference nor of synergism between the two syndromes. The Haas strain of mice showed an unusual sensitivity to X rays which was associated with depletion of blood components and coincident death. The sensitivity of the mice to X rays might be a characteristic of the Haas mouse or the result of an LCM virus-induced alteration in hematopoiesis.

Animals↗