Search PubMed⌕ Search

Biomedical subjects

B Ralovich

Publications and source records attributed to B Ralovich.

At least 37 records · Page 2Linked to original sources

Phage typing of Listeria monocytogenes in Hungary.

Ninety-eight (39.6%) out of 247 Listeria monocytogenes strains isolated from a variety of sources were typable by 27 phases. Of the 31 human strains only 3 belonged to phage types occurring in cattle, sheep and surface waters. A close correlation existed between serotype and phage type of the strains. Serotype 1/2 and 4 strains isolated in Hungary were less frequently typable than cultures originating from France. Phage typing is a useful tool for epidemiological tracing but, for a more effective differentiation, the number of phages should be increased and the method should be standardized.

Animals↗

Specificity of antipyrogenic immunity.

The specificity of antipyrogenic immunity as well as the structural differences of the Enterobacteria responsible for pyrogenicity have been studied. Strains S. minnesota Re 595 and S. typhimurium SL 1102 as well as glycolipids obtained from them, further E. coli 083 and E. coli F 576 as well as the LPS extracted from them were used in the experiments. In conformity with the results of chemical analysis it was found that the method reflected exactly the antigenicity of the receptors responsible for pyrogenicity. Alterations of the antipyrogenic immunity may indicate that the structure of the single endotoxins responsible for pyrogenicity are different in antigenicity.

Animals↗

Pathogenic effect of enterotoxigenic Escherichia coli and Escherichia coli causing infantile diarrhoea.

Macroscopic, light and electron microscopic alterations in ligated rabbit intestinal loops challenged with five standard enterotoxigenic Escherichia coli (ETEC) and twenty-three enteropathogenic E. coli (EEC-I) strains, freshly isolated from infantile enteritis cases, were investigated. Only two O26 : K60 : H11 strains produced enterotoxin. Their living cultures, sterile filtrates of the fluid medium and ultrasonic lysates of the bacteria resulted in pronounced hypersecretion of the intestinal epithelium followed by fluid accumulation and loop dilatation. These two E. coli strains, similarly as the other loop-negative EEC-I strains, were able to penetrate into the intestinal epithelium. In contrast to the standard ETEC strains, the EEC-I bacteria, adhering to the brush border, intruded into the microvilli, multiplied on the outer epithelial cell membrane making close contact with it and, causing, shedding of microvilli, penetrated into enterocytes becoming enclosed in membrane-bound phagosome-like vacuoles, appeared in the lamina propria and elicited mild focal polymorphonuclear infiltration.

Animals↗