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1.
Vopr Virusol ; 43(3): 127-9, 1998.
Artigo em Russo | MEDLINE | ID: mdl-9702812

RESUMO

The liposomal technology for preparing the immunostimulating complex (ISCOM) helped obtain a complex measles preparation whose antigens are represented by the structural proteins of measles virus in the bilayer phosphate-lipid membrane. Immunization of mice with the resultant preparation induced antimeasles antibodies with the maximum titer of antihemagglutinins 1:640 and of antihemolysins 1:1280. The biological activity of antibodies was confirmed in the neutralization test.


Assuntos
Antígenos Virais/imunologia , ISCOMs/imunologia , Vírus do Sarampo/imunologia , Animais , Anticorpos Antivirais/imunologia , Hemaglutininas Virais/biossíntese , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização
2.
Artigo em Russo | MEDLINE | ID: mdl-442890

RESUMO

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.


Assuntos
Corynebacterium/genética , Polimorfismo Genético , Divisão Celular , Corynebacterium/ultraestrutura , Microscopia Eletrônica
3.
Zh Mikrobiol Epidemiol Immunobiol ; (10): 89-92, 1978 Oct.
Artigo em Russo | MEDLINE | ID: mdl-106605

RESUMO

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.


Assuntos
Corynebacterium diphtheriae/ultraestrutura , Polimorfismo Genético , Corynebacterium diphtheriae/genética , Citoplasma/ultraestrutura , Microscopia Eletrônica , Transformação Bacteriana
4.
Zh Mikrobiol Epidemiol Immunobiol ; (6): 58-61, 1979 Jun.
Artigo em Russo | MEDLINE | ID: mdl-111440

RESUMO

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.


Assuntos
Actinomycetales/citologia , Membranas Intracelulares/ultraestrutura , Polimorfismo Genético , Divisão Celular , Corynebacterium diphtheriae/citologia , Protoplastos/ultraestrutura
5.
Zh Mikrobiol Epidemiol Immunobiol ; (2): 86-90, 1978 Feb.
Artigo em Russo | MEDLINE | ID: mdl-208329

RESUMO

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.


Assuntos
Clostridium perfringens/ultraestrutura , Formas L/ultraestrutura , Protoplastos/ultraestrutura , Divisão Celular , Meios de Cultura , Microscopia Eletrônica , Muramidase/farmacologia , Protoplastos/efeitos dos fármacos
6.
Zh Mikrobiol Epidemiol Immunobiol ; (7): 99-103, 1975 Jul.
Artigo em Russo | MEDLINE | ID: mdl-766532

RESUMO

An electron-microscopic study of the negatively-stained S. typhimurium cells from the culture subjected to the action of a specific hyperimmune antiserum in the presence of a complement (the "complement-antibody" system) pointed to increase in the population of morphological signs of cell destruction--an increase in the number of small bacterial fragments. Many cells which retained the configuration of bacterial cells also had signs of specific affection. The determining sign of specificity of the process was the presence on the surface of the great majority of the mentioned morphological types of accumulations of bacterial fragments of the stain in the form of dark stains surrounded by a lighter ring. The stains were as a rule round with the diameter of the dark zone of about 80 A. The light framing of about 30 A in width consisted of 12 subunits. A conclusion was drawn that further experimental analysis was necessary for detalization of this process and reproduction of a complete picture of bacteriolysis.


Assuntos
Anticorpos Antibacterianos , Bacteriólise , Proteínas do Sistema Complemento , Salmonella typhimurium/ultraestrutura , Animais , Coelhos/imunologia , Salmonella typhimurium/imunologia
7.
Artigo em Russo | MEDLINE | ID: mdl-799452

RESUMO

The authors describe the ultrastructure of cells composing the intact population of several S. typhimurium and E. coli strains. Four morphological cell variants were revealed in the population of three salmonella strains. Cells of the first variant had the structure characteristic of all the Gram negative bacteria, and smooth contour surface structures, among which the membrane of the cell wall, its rigid component and the cytoplasmic membrane were differentiated readily. The second variant differed from the first one by the presence of deep individual folds of the surface structures invaginating into the cell. In comparison with the former two types of cells, the two latter variants were characterized by a lesser size, dense cytoplasm and a marked tortuosity of the cell contours in which only the wall components could be revealed. It is supposed that the fourth variant had a structure characteristic of the R-form of cells, the first one--of the S-form, and the second and third variants could be referred to the transitional S leads to R-forms. Increased density of the cytoplasm and rugose character of the surface structures could be attributed to increased dehydration of the cytoplasm of the dissociating cells. No marked polymorphism was revealed in the E. coli cells.


Assuntos
Salmonella typhimurium/ultraestrutura , Brucella/ultraestrutura , Membrana Celular/ultraestrutura , Parede Celular/ultraestrutura , Escherichia coli/ultraestrutura , Formas L/ultraestrutura , Microscopia Eletrônica , Polimorfismo Genético
8.
Artigo em Russo | MEDLINE | ID: mdl-320803

RESUMO

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.


Assuntos
Escherichia coli/ultraestrutura , Membranas/ultraestrutura , Microscopia Eletrônica , Mutação , Polimorfismo Genético
9.
Artigo em Russo | MEDLINE | ID: mdl-6429982

RESUMO

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.


Assuntos
Neisseria meningitidis/ultraestrutura , Microscopia Eletrônica , Microscopia de Contraste de Fase , Neisseria meningitidis/crescimento & desenvolvimento , Fatores de Tempo
10.
Artigo em Russo | MEDLINE | ID: mdl-2500818

RESUMO

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.


Assuntos
Brucella , Lipopolissacarídeos/análise , Brucella/classificação , Brucella/patogenicidade , Brucella/ultraestrutura , Brucella abortus/classificação , Brucella abortus/patogenicidade , Brucella abortus/ultraestrutura , Cromatografia em Gel , Imunoquímica , Imunodifusão , Imunoeletroforese , Lipopolissacarídeos/classificação , Lipopolissacarídeos/isolamento & purificação , Microscopia Eletrônica , Sorotipagem , Especificidade da Espécie , Espectrofotometria Ultravioleta , Virulência
11.
Artigo em Russo | MEDLINE | ID: mdl-463427

RESUMO

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.


Assuntos
Actinomycetaceae/citologia , Actinomycetaceae/metabolismo , Adulto , Antibiose , Biologia , Meios de Cultura , Ativação Enzimática , Humanos , Lactente , Intestinos/microbiologia , Microscopia Eletrônica , Polimorfismo Genético , Fatores de Tempo
12.
Artigo em Russo | MEDLINE | ID: mdl-411293

RESUMO

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.


Assuntos
Corynebacterium/ultraestrutura , Aglutinação , Técnicas Bacteriológicas , Membrana Celular/ultraestrutura , Parede Celular/ultraestrutura , Corynebacterium/patogenicidade , Corynebacterium diphtheriae/ultraestrutura , Meios de Cultura , Especificidade da Espécie , Propriedades de Superfície
13.
Artigo em Russo | MEDLINE | ID: mdl-9381865

RESUMO

The electron microscopic study of cell populations of the first generation of several N.meningitidis strains, isolated from humans and grown on artificial culture medium (Hottinger's serum agar) has made it possible to establish that these organisms are morphologically heterogeneous. It was manifested by the presence of 7 morphological variants of cells in their cultures (different strains have different proportions of these variants): (a) "normal" and similar to normal diplococcal variants; (b) atypically dividing cells; (c) spheroplastic forms; (d) protoplastic forms (typical and atypical); (e) variably gemmating forms; (f) microforms and (g) gigantic forms. These data are of interest for the microbiological diagnosis of meningitis.


Assuntos
Portador Sadio/microbiologia , Meningite Meningocócica/microbiologia , Neisseria meningitidis/ultraestrutura , Humanos , Microscopia Eletrônica , Neisseria meningitidis/classificação , Neisseria meningitidis/isolamento & purificação , Protoplastos/classificação , Protoplastos/ultraestrutura , Sorotipagem , Esferoplastos/classificação , Esferoplastos/isolamento & purificação , Esferoplastos/ultraestrutura
14.
Zh Mikrobiol Epidemiol Immunobiol ; (9): 121-6, 1976 Sep.
Artigo em Russo | MEDLINE | ID: mdl-827882

RESUMO

After 18 hours of growth on selective serum-agar medium C diphtheriae cultures with different toxicogenic activity, and also diphtheroid and Hoffmann's baccillus cultures were removed, washed of the remnants of the nutrient medium and fixed under cold conditions by two combined methods (with glutaric aldehyde-osmic acid--uranyl acetate, and potassium permeanganate--uranyl acetate). The preparations were studied in ultrathin sections. It appeared that corynebacteria had during the stationary phase of development a general structural plan characteristic of Gram positive microorganisms and for all the corynebacterium genus. Cells of diphtheria toxicognic strains had signs of the accelerated (in comparison with other strains) rate of development; the principal mass of toxicogenic cells after 18 hours of growth had morphological signs of the stage of rest. The majority of cells whose toxicogenicity was inconstant had an extensive microcapsule which was also a characteristic element of the diphtheroid and Hoffmann's bacillus ultrastructure. The total thickness of the walls in the cells of toxicogenic strains and of the strains whose toxicogenicity was inconstant constituted 190-200 A; in nontoxicogenic strains, diphtheroid and Hoffmann's bacillus it was from 230 to 320 A. Surface structures of corynebacteria were differentiated better in the cells with toxicogenic activity. In the majority of cells of nontoxicogenic strains and also diphtheroid and Hoffmann's bacillus individual wall layers were differentiated with difficulty.


Assuntos
Corynebacterium diphtheriae/ultraestrutura , Parede Celular/ultraestrutura , Microscopia Eletrônica , Especificidade da Espécie
15.
Zh Mikrobiol Epidemiol Immunobiol ; (9): 54-60, 1985 Sep.
Artigo em Russo | MEDLINE | ID: mdl-2866645

RESUMO

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.


Assuntos
Bordetella pertussis/ultraestrutura , Junções Intercelulares/ultraestrutura , Ágar , Bordetella pertussis/crescimento & desenvolvimento , Caseínas , Membrana Celular/ultraestrutura , Carvão Vegetal , Meios de Cultura , Secções Congeladas , Microscopia Eletrônica
16.
Artigo em Russo | MEDLINE | ID: mdl-3085404

RESUMO

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.


Assuntos
Âmnio/microbiologia , Neisseria meningitidis/ultraestrutura , Linhagem Celular , Parede Celular/ultraestrutura , Humanos , Microscopia Eletrônica , Neisseria meningitidis/crescimento & desenvolvimento , Neisseria meningitidis/patogenicidade , Protoplastos/ultraestrutura , Esferoplastos/ultraestrutura , Propriedades de Superfície , Fatores de Tempo
17.
Artigo em Russo | MEDLINE | ID: mdl-3085411

RESUMO

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.


Assuntos
Âmnio/microbiologia , Infecções Meningocócicas/microbiologia , Neisseria meningitidis/patogenicidade , Âmnio/ultraestrutura , Linhagem Celular , Células Cultivadas , Feminino , Humanos , Microscopia Eletrônica/métodos , Neisseria meningitidis/ultraestrutura , Fagocitose
18.
Zh Mikrobiol Epidemiol Immunobiol ; (11): 24-6, 1984 Nov.
Artigo em Russo | MEDLINE | ID: mdl-6098110

RESUMO

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.


Assuntos
Formas Bacterianas Atípicas/ultraestrutura , Bordetella pertussis/ultraestrutura , Formas Bacterianas Atípicas/isolamento & purificação , Bordetella pertussis/isolamento & purificação , Parede Celular/ultraestrutura , Citoplasma/ultraestrutura , Humanos , Microscopia Eletrônica , Coqueluche/microbiologia
19.
Artigo em Russo | MEDLINE | ID: mdl-6095562

RESUMO

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.


Assuntos
Bordetella pertussis/ultraestrutura , Parede Celular/ultraestrutura , Células Clonais , Citoplasma/ultraestrutura , Microscopia Eletrônica , Fenótipo , Vacúolos/ultraestrutura
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