EFFECT OF EXTRACHROMOSOMAL ELEMENTS OF HEREDITY ON TOXIC PROPERTIES OF YERSINIA PESTIS.

Aim: Elucidation of the role of extrachromosomal elements of heredity in manifestations of toxic properties of Yersinia pestis.

Materials And Methods: The study was carried out in vac- cine strain Y pestis EV76 (pMT1, pCD1, pPCP1) and non-plasmid variants of vaccine EV76 (pMT1⁻, pCD1⁻, pPCP1⁻) and virulent 231 (pMT1⁻, pCD1⁻, pPCP1⁻) strains of Y pestis. Presence of functionally active form of lipopolysaccharide (LPS) in.

[SPECIFICITY OF IMMUNE MODULATING EFFECT OF YERSINIA PESTIS ENDOTOXIN].

Literature and own data on mechanisms, of realization of lipopolysaccharide (LPS) toxic potential of Yersinia pestis in the conditions of a macroorganism are analyzed. 2 modifications of LPS are examined - temperature dependent changes of chemical structure of polymers and a change in their conformation under the effect of micro- and macroorganism factors. A special attention is paid to comparative study of toxic and immune modulating properties of the specified LPS forms.

[Endotoxin tolerance of mice to the effect of lipopolysaccharide and lipopolysaccharide-mice toxin complex of virulent strain Yersinia pestis 231].

Aim: Comparative study of the effect of endotoxin tolerance of mice to the effect of lipopolysaccharide (LPS37) and complex of lipopolysaccharide with mice toxin (LPS37-MT) of a virulent Yersinia pestis 231 strain.

Materials And Methods: Preparations of LPS of highly virulent strain Y. pestis 231 obtained by phenol method from cells cultivated at 37 degrees C as well as commercial preparations of S-LPS and R-LPS of Escherichia coli were used.

[Toxicity and cytokine-inducing activity of lipopolysaccharide of virulent Yersinia pestis 231 strain].

Aim: Determine correlation between toxicity and cytokine inducing activity of parent and conformation modified forms of lipopolysaccharides (LPS) of virulent Yersinia pestis strain.

Materials And Methods: LPS was isolated by phenol method from Y. pestis 231 cells grown at 37 degrees C (LPS37).

[Toxicity of Yersinia pestis EV76 lipopolysaccharides for mice sensitized by D-galactosamine].

Aim: To study toxicity of lipopolysaccharides (LPS28 and LPS 37) of Yersinia pestis for mice sensitized by D-galactosamine (D-GalN).

Materials And Methods: LPS were obtained by the Westphal method from Y. pestis EV76 strain grown at temperatures of 28 and 37 degrees C.

[Effect of Yersinia pestis EV 76 lypopolysaccharides with different levels of toxicity on dynamics of TNF-alpha and INF-gamma synthesis by human monocytes].

Unlabelled: AIM. To study dynamics of synthesis of TNF-alpha and INF-gamma by cell line U-937 human monocytes under the effect of Yersinia pestis EV 76 lypopolysaccharides (LPS) with different levels of toxicity: original LPS28 and LPS37 as well as their conformationally--changed variants with enhanced toxicity--complex of LPS with murine toxin (MT) of Y. pestis, and LPS modified by biologicall active compound (BAC) obtained from human erythrocytes.

[The activation of Yersinia pestis "murine" toxin and endotoxin by hemolyzed erythrocytes from mammalian blood].

Y. pestis "mouse" toxin and endotoxin have been found to be capable of being activated with hemolyzed mammalian red blood cells. The LD50 of the activated endotoxin decreases 5-10 times in comparison with the initial preparation.

Selective monitoring for a Chernobyl effect on pregnancy outcome in Kiev, 1969-1989.

The aim of this investigation was to determine the frequency of adverse pregnancy outcomes in Kiev during the period surrounding the Chernobyl accident on April 26, 1986. Additional effective equivalent doses resulting from the catastrophic irradiation in 1986-1991 was 8.04 mSv for Kiev inhabitants.

[Limited genetic monitoring in Kiev in relation to the accident at the Chernobyl Atomic Electric Power Station].

Frequency of innate developmental defects, perinatal death rate, spontaneous and induced abortions were statistically studied on the basis of primary medical information from archives of two largest maternity hospitals of Kiev for the period between 1969 and 1989. Significant variations in the chosen characters in different years were found, unidirectional changes in time being absent. No increase in the number of innate defects and frequency of spontaneous abortions after 1986 was found.

[Use of aminazine for obtaining isogenic variants of Yersinia pestis strain EV76 with a different set of plasmids].

A method was elaborated for elimination of plasmids from the plague microbe by aminazine. A set of isogenic derivatives of the vaccine strain Yersinia pestis EV76 with different plasmid profiles has been obtained.

[Characteristics of the process of transferrin iron utilization by Yersinia pestis at various incubation temperatures].

The study has revealed that for the utilization of iron contained in transferrin the direct contact of Y. pestis with this metalloprotein is necessary. At 28 degrees C Y.

[Detection of modification-restriction systems in Yersinia enterocolitica].

Four Y. enterocolitica strains (10166, 10373, 2119, 5513) have been studied for the presence of the enzymatic systems of modification-restriction (M-R). As revealed with the use of cross titration, strains 10166 and 10373 contain M-R systems, supposedly of type II.

[Comparison of specific recognition sites of adenine and cytosine DNA-methylase of Yersinia Pestis EV 76 C dam and dcm by Escherichia coli methylases].

Using enzymatic modelling of in vitro methylation of chromosome DNAs from Yersinia pestis EV 76, E. coli 834 and E. coli C600 RII by DNA methylases of Eco RII and Eco dam as well as of DNA hydrolysis of plasmid pBR 322 from the cells of Y.

[Attempt at detecting the systems of host specificity in the bacterial causative agents of plague].

An attempt at revealing the system of host specificity in Y. pestis by the methods of transformation and conjugation has been made. No endonuclease restriction has been detected.

[DNA-methyltransferase of the plague microbe].

DNA-methyltransferases of Yersinia pestis EV, plague agent bacteria were isolated by P-II phosphocellulose chromatography. The methylating activity is eluated by two fractions at the 0.47 M and 0.