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Biomedical subjects

T A Avdeeva

Publications and source records attributed to T A Avdeeva.

At least 19 recordsLinked to original sources
PubMed1981

[Detection of enterotoxigenic Escherichia in patients with diarrhea of undetermined etiology using experimental models].

Feces from 249 adult patients hospitalized due to diarrhea of unknown etiology were investigated. In 65.5% of the patients enterotoxic E. coli (ETEC) producing thermostable enterotoxin were detected by the anal test in suckling mice. As demonstrated by the paw edema test in mice, 79% of such strains produced also thermolabile enterotoxin, the remaining strains belonged to the ETEC variants, known from the literature, producing only thermostable enterotoxin. The antigenic similarity of the thermolabile enterotoxin with cholerogen was confirmed by the phenomenon of paw edema neutralization in mice. Among the cultures isolated from the patients 2 ETEC variants, which could not be differentiated by the test in suckling mice and by the paw edema test in mice and paw edema neutralization, were detected by the intranasal infection of mice.

Animals↗
PubMed1978

Mouse lung oedema caused by a toxic substance of Escherichia coli strains.

Some Escherichia coli strains isolated from patients and instilled into the nostrils of mice cause a rapidly developing fatal, haemorrhagic lung oedema. Lung toxic strains were found in different serogroups, with the predominance of 04, 06, and 018. The toxic material seems to be bound to the cells; the toxin yield is poor by different methods of extraction. The toxic principle causes toxic, haemorrhagic oedema in mouse foot pad test and shows cytotoxicity for AV-3 cells. The "lung toxin" is heat labile and after Sephadex fractionation has a molecular weight of about 100 000 dalton. There is a possible identity with a toxic haemolysin.

Animals↗
PubMed1977

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↗
PubMed1977

[Modeling experimental pollinosis].

Experimental pollinosis was modelled on guinea pigs. The animals were placed in a cell in which an allergen-water-dialyzed extract of ambrosia pollen was dispersed by means of coaxial pulveriser. Homocytotropic antibodies serving as indices of animal sensitization to the specific allergen formed in guinea pigs as a result of aerosol sensitization. Sensitization of the animals to the ambrosia allergen was accompanied by an increase of sensitivity of the broncho-pulmonary apparatus and was characterized by the bronchospastic reaction in resolving inhalation or inrtavenous injection of a specific allergen.

Aerosols↗
PubMed1977

[Experimental sensitizing activity of Neisseria perflava].

In experiments conducted on guinea pigs the sensitizing activity of Neisseria perflava isolated from the mucous membranes of the bronchi of patients with infectious asthma was studied. A possibility of reproducing active skin anaphylaxis after Ovary and of the contraction-test of the tracheal-chain by the neisseria antigens was shown. Neisseria perflava was found to possess a greater sensitizing activity than Staphylococcus aureus and Klebsiella pneumoniae inhabiting the bronchi of patients with infectious asthma.

Animals↗