PubMed Health⌕ Search

Biomedical subjects

L V Parkhomenko

Publications and source records attributed to L V Parkhomenko.

At least 19 recordsLinked to original sources
PubMed1991

[Serotyping of Proteus using a rapid system].

A rapid method for Proteus serologic typing is suggested, based on Soviet commercial diagnostic adsorbed type sera. The rapid system involves replacing two-staged typing with one-staged, making use of polyvalent sera constructed by uniting 8-9 type sera according to the suggested schemes. O- and H-antigens are types in accordance with special tables. Fifteen O-antigens and 4 H-antigens, whose total incidence among Proteus clinical strains is under 2 percent, cannot be typed with the use of this system. The suggested rapid system is suggested as a rapid simple method for typing Proteus clinical strains in intricate epidemiologic situations.

Proteus↗
PubMed1991

[The characteristics of the contact of proteolytic strains of Proteus mirabilis and Klebsiella pneumoniae with enterocytes in vivo].

The relationships of opportunistic P. mirabilis and K. pneumoniae, both having proteolytic properties, with enteric cells in white mice have been studied on a ligated intestinal loop, used as an experimental model, by electron microscopy. This investigation has shown that the strains under study are capable of damaging the membrane of the jagged edge of enteric cells at the distance of the spread of proteolytic metabolites. This damage is reversible, presenting as compensatory protective reaction of the cells.

Animals↗
PubMed1990

[The isolation of a pure culture of Proteus hauseri from associated bacteria].

A simple method for isolation of P. vulgaris and P. mirabilis pure culture from associations with other microorganisms has been developed. Medium for inoculation of a bacterial culture suspected of an association contains glycerin and asparaginic acid. The suggested method is simple and highly effective, reproducible at any bacteriologic laboratory, and is particularly valuable for improving the quality of etiologic diagnosis of pyoseptic diseases.

Culture Media↗
PubMed1990

[The phospholipases of Proteus mirabilis].

The method of screening Proteus for phospholipase activity has been worked out. The study of isolated clones of the same strain, used as an example, has revealed that clones differing in their phospholipase activity also differ in virulence and in some parameters of interaction in the host-parasite system. P. mirabilis phospholipases are supposed to be of importance as one of the factors contributing to the invasive properties of these microorganisms at the stage of overcoming the epithelial cell barrier of mucous membranes.

Animals↗
PubMed1985

[Sensitivity of Proteus mirabilis to drugs in the presence of human blood serum].

For rational antibiotic therapy of patients with persisting bacterial infections, the routine determination of antibiotic resistance in the microorganisms may be insufficient. In this case estimation of the total bactericidal activity of the antibacterial drugs and sera against the causative agents is required. It was shown experimentally that in the presence of human blood sera sensitivity of the P. mirabilis strains to benzylpenicillin, ampicillin, gentamicin, kanamycin and cephaloridin increased, the sensitivity to rifampicin varied and the sensitivity to chloramphenicol and nalidixic acid lowered. The quantitative indices of the sensitivity depended on the biological properties of the strains. The bactericidal activity of the human blood sera lowered under the action of nalidixic acid, chloramphenicol and rifampicin, with the concentrations of the antibacterial drugs being equal to those attained in the blood of patients during chemotherapy. A method for determination of the bactericidal activity of human blood sera in the presence of the antibacterial drugs with the use of P. mirabilis is described. The method is relatively simple and provides satisfactory coincidence of the results indicative of the nonspecific resistance of the blood. This allows the physician to choose the rational antibiotic therapy.

Anti-Bacterial Agents↗
PubMed1980

[Plasmid resistance of the enterobacteria isolated in intestinal disorders in children].

Resistance to antibiotics and sulfanilamides was determined in enterobacteria (E. coli, Pr. mirabilis, Sh. sonnei, Sh. flexneri) isolated from children with intestinal disorders. Elimination of the resistance determinants in polyresistant strains, conjugation of R plasmids (75 per cent in Pr. mirabilis, 70 per cent in E. coli, 78 per cent in Sh. sonnei, 69 per cent in Sh. flexneri), mobilization of nonconjugative plasmids on triple crossing and capacity of R plasmids for repression of the F-factor functions were studied. The data of the study are evident of the plasmid background in enterobacteria isolated from children with intestinal disorders and confirm the plasmid nature of the resistance in the predominating number of the strains. It is suggested that Proteus plays a significant role in the prevalence of plasmid resistance among enterobacteria.

Child↗
PubMed1975

[Comparison of the physiological and biochemical indices of the phagocytosis of ram erythrocytes by macro- and microphages].

Morita and Perkins' method was applied to the study of the stage of ingestion and destruction of an antigen (sheep erythrocytes) in the macrophages of peritoneal exudate of rabbits and rats and in the microphages of rabbit pleural exudate. Ingestion and intracellular destruction of the antigen were accompanied by intensified respiration and glycolysis of phagocytes. Respiration of the three types of phagocytes at two stages of phagocytosis and also the digestive capacity of microphages proved to be sensitive to cyanide and colchicine. The latter failed to influence the ingestion of the antigen by the three types of phagocytes and its digestion by macrophages. The differences in the metabolism routes of macro- and microphages in intracellular destruction of the antigen was postulated. An intensification of the phagocytic activity after the immunization was characteristic of rabbit and rat macrophages.

Animals↗
PubMed1975

[Results of a quantitative study of the interaction of pathogenic enterobacteria with a cell monolayer].

A study was made of the cytopathic effect and dynamics of intracellular reproduction of S. typhimurium and shigellae in the monolayer of HeLa cells, macrophages (monocytes) of the peritoneal exudate of rabbits and rats and microphages (granulocytes) of the pleural exudate of rabbits. The presence of bactericidal mechanism in the host cell to the invaded infectious agent is postulated. An important role of the cell component of defence in insensibility in shigellosis is supposed.

Animals↗
PubMedDate not supplied

[The mechanisms of Proteus mirabilis resistance to the bactericidal action of blood serum].

When studying sensitivity of Proteus mirabilis to bactericide effect of blood serum the resistance to alternative way of the complement activation was found in a number of strains. The population of cells with morphologically determinable changes of the surface structures resistant to bactericide effect of the serum is formed as affected by the blood serum of the culture P. mirabilis. Proteus proteases capable to inactivate the complement components are one of the factors of P. mirabilis resistance to bactericide effect of the complement.

Blood Bactericidal Activity↗
PubMedDate not supplied

[The characteristics of the initial link in the intestinal lesion by opportunistic Proteus mirabilis bacteria].

Interaction of Proteus mirabilis with the intestine epithelium in white mongrel mice has been studied by means of bacteriological, toxicological and electron microscopic methods. Introduction of the agar culture of bacteria to the intestine lumen has permitted finding its general toxic action on enterocytes and other cell elements of epithelium which was accompanied by a potentiation of the striated margin membrane degradation but caused no destruction of cells. A damaging factor of protei was connected with the thermostable large-molecular fraction of cultural fluid of bacteria and its action was traced at the first hours of the bacterial contact with the mucous surface of thin intestine. Preliminary weakening of protective barriers of the intestine mucosa permitted protei to penetrate deep into the tissue through the intercellular slots. Colonization of the intestine lumen wall zone by the proteus is a necessary condition of the above-mentioned changes.

Animals↗
PubMedDate not supplied

[A method for determining phospholipases in microorganisms].

A method is suggested for the determination of bacteria phospholipases in dense nutrient medium. The medium contains the egg-yolk solution, buffer pH 9.2, meat extract, calcium chloride and toluidine blue. The enzyme activity is estimated by the diameter value of the medium clarification zone around the bacterial mass inoculation by injection into an agar plate. It is possible to study 6-8 strains on one Petri dish. This method is a simple one and thus it can be used in the bacteriological practice when determining phospholipases of bacteria, especially in strains of those species where this enzyme is a pathogenicity factor.

Bacteria↗
PubMedDate not supplied

[Proteus adhesion to intestinal epithelium].

The adhesive properties of Proteus strains isolated from different sources have been studied under conditions similar to the real interaction of microorganisms with the epithelial cells of intestine. A comparison of the adhesive properties of Proteus and of colon Bacillus has shown that the value of the strong adhesion to the mucosa of Proteus isolated under enterocolitis at the same bulk concentrations of the infectious suspension is 2-3 order less than that of E. coli. The adhesion of Proteus to the surface of epithelial cells begins at bulk concentrations exceeding those for the colon Bacillus by 3-4 orders. Besides, a toxic effect of number of freshly isolated Proteus strains on the epithelial cells of intestine mucosa is observed. Strains isolated from patients with diarrhea and from environment differed from each other in the studied criteria. A conclusion is drawn that at the initial stage of the interaction with the intestine mucosa the Proteus strains differ considerably from the indigenous strain of the colon Bacillus in the ability to colonize the epithelial surface.

Animals↗
PubMedDate not supplied

[The effect of subinhibitory concentrations of antibiotics on the adhesion of enterobacteria].

It is impossible to determine rigidly a net result of the influence of antibiotics on the interaction between parasite and host cells, as many factors participating in this process are not studied. Adhesion of microorganisms is one of the essential mechanisms of the above interaction. Antibiotics with a different mechanism of action in the subinhibitory concentrations affecting viability of microbes either slightly or nowise have been studied for their effect on adhesion on a model of the intestine section of human embryos and experimental animals. Most of antibiotics influenced differently adhesion of the microorganisms, that also depended on the species attribution of the latter. The accelerated selection of resistance during a successive passage via the suggested adhesion system was observed. The data obtained elucidated certain mechanisms of the effect of antibiotics on the microbial populations at the initial phase of the infectious process and under the primary contamination of mucosa.

Animals↗