[Survival of probiotic microorganisms in the conditions in vitro imitating the process of human digestion].

PURPOSE OF THE STUDY: Assessment of survival bifidobacteria and lactobacteria under the conditions in vitro, simulating digestion in human stomach and intestine, and study of survival probiotic and indigenous microorganisms in co-cultivation on solid nutrient medium. MATERIALS AND METHODS: Probiotic microorganisms from commercial preparations Bifidobacterin and Lactobacterin, clinical isolates lactobacillus (Lactobacillus acidophilus No 1, L. brevis No 2) were used in experiments. Survival study of probiotic microorganisms was performed on a model in vitro, simulating the process of digestion in the human body. Assessment of the relationship of probiotic microorganisms and indigenous microorganisms was carried out in co-cultivation in vitro on solid nutrient medium. RESULTS: A significant reduction in the number of viable probiotic microorganisms during their incubation in model media was set as well as suppression of probiotic microorganisms growth by cultures of a clinical strains of lactobacillus, corresponding to biocompatibility by type "host against probiotic". CONCLUSION: While choosing probiotics in the treatment of dysbacterioses the character of relationship between probiotic microorganisms and indigenous microorganisms of a patient is recommended to be preliminarily tested. Also microorganisms of own microflora should be stimulated using modern prebiotics.

[Comparative assessment of survival of probiotic microorganisms from commercial preparations under the conditions in vitro].

PURPOSE OF THE STUDY: Assessment of survival of probiotic microorganisms from commercial preparations under the conditions in vitro simulates digestion in human stomach and intestine. MATERIALS AND METHODS: Probiotic microorganisms from domestic and foreign commercial preparations were used in experiments. Study of survival of probiotic microorganisms was carried out on the model in vitro simulates the conditions of digestion in the human body. RESULTS: A significant reduction in the number of viable probiotic microorganisms in the 20 of 23 studied commercial preparations during their incubation in the model media is established. Probiotic microorganisms in the preparations Bactisubtil, Sporobacterin and Biosporin possess a good survival under the conditions in vitro. CONCLUSION: The selection of probiotics for the correction of intestinal microbiocenosis requires an individual approach that takes into account the character of relations of probiotic microorganisms and indigenous microorganisms of patient as well as the possibility of using advanced prebiotics in the combine treatment of dysbacteriosis.

[Experimental study of sensitivity of probiotic microorganisms to antibacterial drugs].

PURPOSE OF THE STUDY: Investigation of sensitivity of probiotic microorganisms to antibacterial drugs. MATERIALS AND METHODS: Probiotic microorganisms from domestic and foreign commercial preparations were used in experiments. The study of sensitivity of probiotic microorganisms to antibacterial drugs was carried out using solid nutrient medium containing calculated amount of antibacterial drugs. RESULTS: Probiotic microorganisms are mainly sensitive to the representatives of the major classes of antibacterial drugs. Only some of the studied microorganisms are resistant to 1-4 antibiotics. CONCLUSION: When choosing a probiotic in the treatment of dysbacteriosis need to consider whether th antibiotic therapy was carried out. The use of antimicrobial drugs, even in therapeutic doses, reduces the viability of probiotic microorganisms and their survival in the gut.

[Evaluation of the protection efficiency of secretory antibodies in experimental Yersinia infection in guinea-pigs immunized with polyvalent vaccine against this infection].

The paper presents the results of experiments to elucidate the protection efficiency of secretory antibodies via parenteral and oral inoculation with pathogenic Yersinia in guinea pigs immunized with a polyvalent yersiniasis vaccine designed on the basis of the pseudotuberculosis microbial strain that synthesizes the F1 antigen of a plague microbe. Immunization of guinea pigs with the polyvalent yersiniasis vaccine protects experimental animals against pseudotuberculosis, intestinal yersiniasis, and plague infections.

[Temperate Legionella bacteriophage: discovery and characteristics].

For the first time, temperate Legionella bacteriophage was isolated from organs of guinea pig infected with Philadelphia 1 strain of Legionella pneumophila. Negative colonies of bactriophage from 1.5 to 2.5 mm in diameter were detected. Central part of them was transparent and surrounded by peripheral zone of partial lysis. Electron microscopy showed that corpuscles of the phage consist from multifaceted elongated head of stretched hexagonal form and short tail. The bacteriophage lyzed bacteria, which cause Legionnaires' disease, and also had certain lytic activity against causative agent of tularemia.

[The role of the Yersinia plasmid of calcium-dependency in the formation of the plague immunity].

It was shown that viable variants of the Y. enterocolitica microorganisms containing the plasmid of Ca-dependency (native one or from EV/ I Y. pestis cells) were more immunogenic to plague-infected guinea pigs than isogenic non-plasmid variant. As a result of studying the protective properties of the bacteria Y. enterocolitica sub-cellular fractions it was determined that the largest quantity of immunogen per unit of protein was accumulated in the cultures of bacteria's plasmid variant. The aggregate of the obtained experimental data suggested that there was a non-identified protective antigen (or antigens) for guinea pigs to be encoded by chromosome's DNA. Besides, the Ca-dependency plasmid gene products take part in its excretion and, as the factors of pathogenicity, provide survivability of the Y. enterocolitica microorganisms in the host organism, increasing thus the immunogen accumulation in it.

[The antibody spectrum after the inoculation of sensitive animals with Yersinia pestis and Yersinia pseudotuberculosis bacteria]. / Spektr antitel pri vvedenii chuvstvitel'nym zhivotnym bakterii Yersinia pestis i Yersinia pseudotuberculosis.

Antibody spectra in the sera of guinea pigs and white mice infected with Y. pestis and Y. pseudotuberculosis, the causative agents of plague and pseudotuberculosis, were determined with the use of immunoblotting. The amount of antigens, found to produce humoral immune response both in plague and in pseudotuberculosis was, on the whole, considerably less (5-6 times) in white mice than in guinea pigs. The animals were found to produce antibody response to plasmid-specific (Yop) Y. pestis antigens with with molecular weights 76, 41 and 34 kD and Y. pseudotuberculosis antigens with molecular wt of 41, 34 and 25 kD. Differences in the character of humoral immune response induced in guinea pigs by killed and live Y. pseudotuberculosis were determined. In the animals inoculated with killed bacteria these differences consisted in the absence of antibody formation to the immunodominant antigen with a molecular weight of 62 kD and in the increase of antibody response to antigens with molecular weights of 36 and 21 kD, supposed to be related to Y. pseudotuberculosis pathogenicity factors and to possess protective properties.