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M M Livshits

Publications and source records attributed to M M Livshits.

18 recordsLinked to original sources
PubMed1988

[Mechanism of the interaction of chloramine with Pseudomonas aeruginosa].

The disinfecting effect of chloramine on P. aeruginosa depends on the concentration of this disinfecting agent, the concentration of P. aeruginosa and the period of exposure, with consideration for the time of attaining equilibrium between the concentration of chloramine and P. aeruginosa, affinity between the disinfectant and bacterial cells, the number of chloramine-binding sites on a bacterial cell, the admixture of organic substances, pH and other environmental characteristics. The interaction of chloramine and P. aeruginosa can be subdivided into two stages: (1) the binding of the disinfectant by bacterial cells and (2) the death of the microbes. The mathematical description of the process of disinfection requires that the main characteristics be expressed in molecular parameters and the time factor be correlated with the terms of attaining the equilibrium for free and bound chloramine. The average number of binding sites for chloramine on a bacterial cell and the affinity constant of chloramine to binding sites have been estimated.

Chloramines↗
PubMed1985

[Results of the comparative use of virological and bacteriological control of routine disinfection in maternity homes].

Bacterial viruses were often detected in washings from different environmental objects; not infrequently, the inoculation of washings from the same objects resulted in the growth of Escherichia coli. The expediency of making parallel tests of washings from these objects for the presence of wild strains of bacterial and viral cultures both during the control of disinfection measures and the determination of the effectiveness of disinfection agents is shown.

Bacteria↗
PubMed1984

[Use of monoclonal antibodies in immunoenzyme analysis for demonstrating antigenic monovalency].

To prove the monovalence of the antigen a method has been developed consisting of ELISA with the use of monoclonal antibodies in combination with the antibody neutralization test. Yersinia pestis capsular antigen was disintegrated by heating at 100 degrees C for a short time and subsequently passed through a column packed with Sephadex G-50. The portions of the eluate, showing high activity in the antibody neutralization test and low activity in ELISA (the double antibody sandwich scheme), contained mainly the monovalent antigen. This antigen was replaced by the polyvalent antigen from the antibody complex, but if such complex had been previously fixed by treatment with glutaraldehyde, no replacement of the monovalent antigen by the polyvalent one occurred.

Animals↗
PubMed1981

[Serum antibody and splenocyte immunoglobulin receptor affinity in multiply immunized mice].

In the process of repeated immunization of CBA mice with soluble Pasteurella pestis capsular antigen the concentration of antibodies in the blood increased, but the dynamics of antibody affinity in the serum did not correlate with this process. For the first time the average splenocyte receptor affinity was measured, and this characteristics was found to exceed that of the corresponding serum antibodies. To explain the heterogeneity of antibodies, two hypotheses have been proposed. One hypothesis states that the heterogeneity of antibodies is determined by the cyclic character of antigen concentration at the site of injection, while according to the other hypothesis, it is determined by the interaction of immunoglobulins of different idiotypes with idiotypic antibodies.

Animals↗
PubMed1979

[Determination of the concentration of active centers and the antibody heterogeneity index by using the precipitation in fluid reaction].

Equivalence zone in the precipitation test was characterized by the fact that the number of the antigen determinants was equal to the number of active antibodies centres, irrespective of the heterogeneity of the latter. This permits to assess the antibody concentration in the values of the antigen valency. The new method of determination of the antibody heterogeneity index is based on recording the titre of the antigen and antibodies in the equivalence zone.

Animals↗
PubMed1977

[Use of serologic reactions for determining the concentration of the determinants of an antigen and its valence].

By the serological tests with the erythrocytic diagnostic agents it is possible to estimate the concentration of the determinants in the antigenic preparation under study. For this purpose it is necessary to have at one's disposal the data on the molecular weight and concentration of the reference antigen, valence of erythrocytes loaded with the antigen or antibodies, and antibody heterogeneity index. If these values are known, then one can calculate the concentration of antigenic determinants in terms divided by the valence of the reference antigen. With the aid of pure antibodies preparation obtained with the immunosorption procedure it is possible to measure the determinant concentration of the antigen tested and the valence of the reference antigen. For the capsular antigen of plaque bacilli the valence was estimated by two independent methods and in both cases it was close to 10. The valence of the reference capsular antigen permits to calculate the concentration of the antibody molecules in the hyperimmune sera without isolation of pure antibodies.

Animals↗
PubMed1976

[Use of erythrocyte diagnostic agents for the determination of integrative association constants].

The authors described a method of determination of integrative association constant differing from intrinsic association constant by the value of the valency of macromolecular antigen. The method is based on the using of erythrocytes on whose surface one of the components is fixed, whereas the other is in free state. Application of equations was demonstratedon a number of examples with determination of integrative association constant. The data obtained permitted to assess qualitative peculiarities of the antigenic and antibody erythrocytic diagnostic agents.

Antibodies↗
PubMed1976

[Normal antibodies and immunologic reactivity].

Antibodies to the capsular antigen of plague causative agent were found in the serum of many nonimmunized mice of 6 strains, but none were found in mice of the DBA/2 strain. After the administration of the capsular antigen to mice of different strains cells forming the antibodies to the antigen administered were revealed in a quantitative correlation with the natural antibody level. An association was revealed between the level of natural antibodies and the number of antibody-forming cells in the spleen of nonimmunized mice; it could be described by an equation almost all of whose members represented constant values with a definite quantitative characteristics. To check the suggested equation the concentration of immunoglobulins in the blood of mice was compared with the number of plasma cells in the spleen; a satisfactory correlation was revealed between them.

Animals↗
PubMed1975

Cyclic kinetics and mathematical expression of the primary immune response to soluble antigen. VI. The possibility of prediction of plasma cell reaction in the spleen of mice immunized with soluble antigen.

A mathematical expression of the accumulation of the plasma cells in the spleen of CBA mice immunized intraperitoneally is presented. The dependence of the plasma cell reaction in the spleen on the kinetics of antigen concentration in the blood was confirmed. For the transition from antigen to plasma cells, index A was proposed. The mean values of index A were used for comparison of the calculated and experimental values of the plasma cell reaction and the recorded differences were not great. In a similar way, index A was used for prediction of plasma cell accumulation in the spleen of animals, immunized with a mixture of two soluble antigens -- capsular antigen of Pasteurella pestis and complete antigen of Francisella tularensis. The calculated values of plasma cell reaction corresponded to experimental values.

Animals↗
PubMed1975

[The possibility of predicting the degree of plasmacyte reaction in response to administration of soluble antigen to mice].

The work is devoted to the mathematical description of the accumulation of plasma cells in the spleen of CBA mice immunized intraperitoneally. A dependence between the dynamics of the soluble antigen concentration in the blood and the plasmocytic reaction in the spleen was confirmed under experimental conditions. Index A was suggested for detection of a change from the antigenic function to the accumulation of plasma cells. The mean values of index A were used to compare the calculated values of the plasmocytic reaction and the experimental data; differences between these values were insignificant. Analogously index A was used for predicting the accumulation of plasma cells in the animals to which a mixture of the two soluble antigens (a capsular antigen of the causative agent of plague and a complete antigen of the causative agent of tularemia) was administered. The calculated values of the plasmocytic reaction in this experiment satisfactorily correlated with the data obtained experimentally.

Animals↗