Biomedical subjects

V V Vysotskiĭ

Publications and source records attributed to V V Vysotskiĭ.

At least 19 recordsLinked to original sources

PubMed1989

[Immunochemical characteristics and serologic properties of lipopolysaccharides isolated from various Brucella species using various extraction methods].

The results of the comparative analysis of LPS isolated by different methods of extraction from the cultures of several Brucella species differing in their virulence are presented. Purified LPS preparations have been obtained from Brucella virulent and vaccine strains by using such methods as water-phenol extraction, Boivin's method, mild alkaline hydrolysis of the antigen according to Boivin's procedure. The presence of certain relationship between the method used for the extraction of Brucella LPS to be compared and their chemical composition, immunological characteristics and serological activity has been established. As shown in this investigation, in the process of the preparation of a highly sensitive diagnosticum for the passive hemagglutination test the use of LPS obtained from Brucella virulent strains, but not from the vaccine strain, by the method of mild alkaline hydrolysis according to Boivin's procedure is expedient. The data presented in this work indicate that the soluble complex of lipid A obtained from Brucella LPS has been found to possess serological activity. The results of the study of the serological properties of lipid A indicate that the lipid component may also play a certain role in the manifestation of the serological activity of Brucella LPS.

Brucella↗

PubMed1987

[Cytopathogenic action of intact and antibiotic-altered populations of Bordetella pertussis on a human amnion cell culture].

Cytopathogenic and adhesive action of intact B. pertussis population and population changed under the effect of antibiotics was studied comparatively. It was shown that the level and character of the changes in the cell culture of line FL human amnion depended on the antibiotic used in the experiments. Populations of B. pertussis changed under the effect of tetracycline had the highest cytopathogenic and adhesive activity, while the activity of the population changed under the effect of erythromycin was the least. The decrease in the cytopathogenic and adhesive activity of B. pertussis changed under the effect of erythromycin correlated with lowering of the toxicity and the loss of the main agglutinogenic factors of the surface of the bacteria cell wall. The increase in the toxicity of the population changed under the effect of tetracycline was accompanied by changes in the cytopathogenic and adhesive properties of the culture.

Amnion↗

PubMed1986

[Electron microscopic study of the interaction of cultures of Bordetella pertussis altered by antibiotic action with a human amniotic cell culture].

The adhesive properties of B. pertussis subjected to long-term subcultivation on nutrient media with antibiotics were studied with electron microscopy and it was shown that under the action of erythromycin the adhesive capacity of B. pertussis markedly decreased. Subcultivation on media with tetracycline did not lower the adhesive activity of B. pertussis. Changes in the adhesive properties of B. pertussis under the action of the antibiotics correlated with changes in toxicity, serovars and ultrastructure of the bacteria in the population.

Amnion↗

PubMed1986

[Cellular ultrastructure of the meningococcus when incubated in a continuous culture of human FL-line amnion].

Some details of the ultrastructure of several meningococcal strains having had contacts with cells in continuous human amnion cell culture FL for 6 hours to 2 days have been defined with greater precision by means of electron microscopy. The study has shown that the contact of meningococci with the tissue culture is accompanied by the appearance of meningococcal forms with the defective cell wall, similar to L-forms: spheroplast, protoplast, gigantic cells and microcells, as well as budding variants. The meningococcal variants with the defective cell wall, appearing in the cell culture, and the forms occurring (in different proportions) in "ripe" meningococcal populations developing in the culture media for a long time and isolated from a human body have been found to have no essential differences in their fine structure. These data indicate that any external influences (meningococci are highly sensitive to such influences) produce sufficiently rapid changes, similar to L-transformation, in the fine structure of these microorganisms.

Amnion↗

PubMed1986

[Electron microscopic study of the cytopathogenic action of meningococci in a continuous human amnion cell culture].

The electron-microscopic study of the interaction of meningococci with continuous human amnion cell culture F1 has revealed that this process comprises 3 stages. The study has shown that, following the adhesion of meningococci to the surface of cells F1, these cells are invaded by individual coccal forms of meningococci. In response to infection vacuoles appear in the cytoplasm of the cells. Meningococci are either phagocytosed inside these vacuoles, or their release into the intercellular space and the death of the infected by meningococci are observed. When the cells are infected by cytopathogenic strains, the infectious process results in the appearance of degenerative changes in the cells.

Amnion↗

PubMed1985

[Cryofractographic study of intercellular junctions in the populations of agar-cultivated Bordetella pertussis].

The characteristic feature of replicas obtained from the freeze-fractures of B. pertussis unfixed cultures developing on casein charcoal agar for 1-7 days is the associative growth of highly polymorphic cells, ensured by the ramified system of intercellular connections (IC) formed by the derivatives of the outer layers of the cell wall. This proves that the associative location of bacterial cells, linked by numerous IC, in the preparation is not the artefact appearing in the process of their chemical fixation. In replicas obtained from the freeze-fractures of B. pertussis cultures, previously fixed with glutaraldehyde, osmic acid and uranyl acetate, oval cells with the cytoplasm having a relatively homogeneous structure and with the smoothed-out three-layer cell wall prevail. As a rule, IC are limited to the sites of direct contacts between individual cells.

Agar↗

PubMed1984

[Morphological heterogeneity of Bordetella pertussis populations and clones (based on electron microscopy data)].

Populations belonging to different serovars of B. pertussis museum strains and antibiotic-resistant clones obtained from them have been studied by electron microscopy. As a result, morphological heterogeneity and differences in the ultrastructure of the cells with respect to the cell-wall structure, the character of the cytoplasm, the size of the cells, cytoplasmic inclusions and intracellular links have been demonstrated and, proceeding from these data, two main morphological variants of the cells have been defined. The cells of the morphological variant characterized by the pliciform surface of the outer membrane and the pronounced periplasmic space prevail among the populations of the museum strains. The possibility of the isolation of antibiotic-resistant clones, differing in their morphological structure and functional properties from the initial population, has been shown. The morphological diversity of B. pertussis population is the necessary condition for the existence and development of microbial populations.

Bordetella pertussis↗

PubMed1984

[Ultrastructure of freshly isolated strains of Bordetella pertussis].

The study of the electronograms of B. pertussis strains isolated in the foci of pertussis revealed the existence of the morphological variants of these cells, differing in the character of the cell wall, the state of the cytoplasm, the presence of amorphous inclusions of medium electron-optical density. The morphological variants did not correlate with the character of B. pertussis colonies isolated from blood-charcoal agar. The ultrastructure of the cells belonging to the second morphological variant was similar to that of the cells from the museum strain, altered by tetracycline treatment in the course of the experiment.

Atypical Bacterial Forms↗

PubMed1984

[Ultrastructure of the meningococcus in logarithmic and stationary development phases].

The complex study of Neisseria meningitidis cultures A-208 in the time course of their development has disclosed that broth cultures in the logarithmic and stationary phases of their development are most valid on account of all their biological properties (the specific character of the reaction of agglutination, viability, the morphology of colonies and cells in light and electron microscopy). The use of scanning electron microscopy has made it possible to reveal bubbly endotoxin excretion in N. meningitidis and funnel-shaped depressions on their surface corresponding, probably, to nucleoid epicenters . In ultrathin sections some previously unknown features of the ultrastructure of N. meningitidis in the logarithmic and stationary phase of their development have been detected: (a) the morphological heterogeneity of N. meningitidis represented by cells of the "light" (L) and "dark" (D) types; (b) the surface structures of meningococcal cells from the cultures in the stationary phase of development show the tendency to smoothing out, which is accompanied by their sharper differentiation.

Microscopy, Electron↗

PubMed1983

[Effect of penicillin and the habitat medium in the body of bacterial carriers on the intercellular bonds in populations of the meningococcus and pertussis microbe].

The relationship of the bacterial cells in populations and their adhesion activity is at present one of the research priorities in microbiological studies. The stimulating effect of penicillin on the development of morphologically different intercellular bonds (IB) in populations of the pertussis causative agent and first of all derivatives or evaginates of the cell wall membranes was observed. Morphologically similar systems and polytubular IB were detected in populations of meningococcal strains isolated from carriers having no signs of the disease. Correlation between the after-effect of penicillin and the presence of the causative agent in bacterial carriers was shown. Unknown systems of interlacing tubular structures not directly bound with the cells, the walls of which were single contour membranes were determined in the meningococcal populations treated with penicillin. IB were observed in the population in the form of transpopulation cords. Morphologically different IB playing the role of specialized organelles might be considered as factors of the functional unity of the bacterial population as a multicellular system.

Bordetella pertussis↗

PubMed1982

[Ultrastructural changes in populations of the pertussis microbe exposed to antibiotics].

The ultrastructural changes in the populations of the pertussis causative agent maintained for a prolonged period of time on nutrient media containing antibiotics were studied with the method of electron microscopy. Significant changes in the ultrastructure of the cells and the population composition due to the effect of tetracycline, levomycetin or erythromycin were observed. The ultrastructure of the populations affected by penicillin or streptomycin and their biological properties were most similar to those of the initial strains. The electronogrammes revealed morphological heterogeneity of the initial and experimental cultures and changes in the subpopulation composition induced by the antibiotics.

Anti-Bacterial Agents↗

PubMed1979

[Heteromorphism of the corynebacteria. III. D- (dark) and C- (clear) cell types and multiseptate specimens].

A population of Corynebacterium diphtheriae may consist of cells with accented (osmiophilic) cytoplasm (cells of the "dark" type, or D type) and cells with cytoplasm having no pronounced osmiophilic properties (cells of the "clear" type, or C type). The divergence of the population into cells of the D and C types occurs at the stage of cell division, the original mother cell being able to divide into 2 or more individual cells belonging to different types (elongated multiseptate cells). At the same time no morphological disturbances in septation may be observed. The ability of each type of cells for division into the corresponding individual daughter cells indicates their being biologically valid. The mixed (D--C) population of Corynebacterium diphtheriae is considered to be a sign of the dissociation of bacterial culture.

Actinomycetales↗

PubMed1979

[Heteromorphism of corynebacteria. II. Microcells].

The formation of microcells is one of the manifestations of the heteromorphism of Corynebacterium. It can occur in 6 ways, of these, 3 are possible during septation (chaotic septation of gigantic macroforms, irregular multiseptation of elongated organisms, and microcells appearing as inserts at the sites of the septum formation), and 3 in undividing cells (microcells at the edge segments of the protoplast, exogemmation, endogemmation). The analysis of the ultrastructure of microcells indicated the possibility of their independent existence for a certain period of time.

Cell Division↗

PubMed1979

[Morphology of the bifidobacteria by light and electron microscopy and their biological properties].

The morphology and the acid-producing, antagonistic and enzymatic activity of the strains of bifidobacteria isolated from the intestine of adults and children were studied. Bifidobacteria showed a considerable polymorphism, all the strains were antagonistically active. The strains isolated from adults were found to have greater acid-producing activity; the predominant species were B. longum and B. adolescentis, and in children B. bifidum were also isolated. The characteristic feature of B. longum strains was the presence of a slime-like layer and formations resembling bubbles around bacterial cells. The stains with greater physiological activity were found to have an extensive mesosomal complex, as well as a great number of volutin granules.

Actinomycetaceae↗

PubMed1978

[Heteromorphism of corynebacteria. I. Macrocells].

A possibility of formation of macrocells (MaC) of diphtheria bacilli was expressed to a different degree; the extreme expression are giant and supergiant forms. Giant forms with section dimension of 3--5micron retained their capacity to disorderly septation with the resultant formation of microcells (MiC). Apparently some of the septa were not realized. Supergiant forms were revealed as a layer and its transverse section. The length of the latter reached 30micron with the transverse section of 2--3micron. The layer has festooned contours with shallow invaginations, but marked day-like cuttings into the body (in case of transverse layer section). Septation of supergiant form was abortive in character. Both forms had homogeneous cytoplasm surrounded by a cell wall. In the supergiant form the latter was morphologically defective in the deepest part of the invaginates. The ultrastructure of both bacterial forms pointed to their rapid growth; however, the supergiant form was likely to be doomed to degeneration and chaotic disintegration.

Corynebacterium diphtheriae↗

PubMed1978

[Protoplast fragmentation as one of the possible mechanisms of L-transformation of bacteria (Clostridium perfringens)].

As revealed, the action of lysozyme on the cells of Clostridium perfringens BP-6K led to the formation of not only typical spheroplasts, but also of cells whose peripheral parts of the cytoplasm were fragmented by membrane component. Small bodies framed by the membrane proper and containing granular and fibrillar components were formed. They were polymorphic in osmium treatment, and had smooth contours in preliminary use of aldehyde fixation. In the latter case a dense lumpy material analogous to the one which fills the periplasmic zone and serves as a rigid wall component formed at the surface of the protoplasm and bodies-fragments. In case of escape of the bodies into the external environment through the perforations in the cell wall the principal mass of the protoplast remains intact. The morphology of the bodies-fragments indicated a principal possibility of their autonomic existence. It is supposed that the phenomenon described could serve as one of the mechanisms of L-cell formation.

Cell Division↗

PubMed1977

[Ultrastructure of LLR-mutants of E. coli K12].

The author studied the ultrastructure of two spherical E. coli K12 mutants (llr) obtained under the effect of N-nitroso-N-methylurea. Seven morphological types of cells differing from one another by shape, size and cytoarchitectonics were distinguished. Superficial structures of the majority of the cells were represented by the membranes of the cell wall and the cytoplasmic membrane of common structure. Some of the cells had only one membrane coat and a high electron optic density of the cytoplasm. Transitional forms of cells were also encountered. The ultrastructure of each morphological type in the population of the llr-mutants was described in detail. The capacity of the mutants to vacuolization, to the intra- and extracellular budding, and also the ability to form multiple membrane structures resembled analogous structures of stable L-forms of the Gram-negative microbes. The problems of morphological differentiation of the L-forms and of the llr-mutants, and also problems connected with the formation of the multiple membrane structures and small elemental bodies in the cells of the llr-mutants are discussed.

Escherichia coli↗

PubMed1977

[Extracellular material of some representatives of the genus Corynebacterium (the electron microscopic aspect)].

At the active developmental phases (up to 2 days) cells of toxigenic and nontoxigenic corynebacteria form extracellular vesicle-like material of two types which can be revealed both on whole cells set off by metal and stained negatively, and in ultrathin sections. Extracellular material of the first type is a derivative of an extensive membranous coat of corynebacteria and is formed as a result of its fragmentation. Vesicles of this type are devoid of electron microscope-dense content, have no tendency to coalescence, and fail to promote cell agglutination. Extracellular material of the second type is primarily formed by local thickening of the surface wall layer limited by its external dense layer and the main massif. These thickenings are filled with a microgranular substance of medium electron optic density; after accumulation this substance is released into the external environment. Vesicles of this type promote cell agglutination. Undoubtedly, extracellular material of the second type has a direct relation to the cell metabolic processes. Extracellular material of both types is encountered in all the cultures grown both on hard and in fluid nutrient media. However, in the latter case the process is apparently much more intensive. There is strict correlation between the morphology of the extracellular material and strain signs of the culture, although material of the second type is found to prevail in the cells from cultures possessing toxigenic activity.

Agglutination↗