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1.
Zh Nevrol Psikhiatr Im S S Korsakova ; 124(7. Vyp. 2): 96-100, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-39175247

RESUMEN

Neuromyelitis optic spectrum diseases (NMOSD) are a group of rare neuroimmunological diseases involving mainly the optic nerves and spinal cord, to a lesser extent the brain, and causing severe exacerbations that lead to persistent disability of patients. For many years, opticoneuromyelitis was considered a prognostically unfavorable variant of the course of multiple sclerosis (MS), however, in 2004, specific autoantibodies to aquaporin-4 were found in such patients, which made it possible to isolate NMOSD into a separate group of demyelinating diseases other than MS. Due to similar clinical signs and the predominantly remitting course of diseases, it is often difficult to make a correct diagnosis and, accordingly, prescribe effective therapy, which often leads to incorrectly selected therapy with incorrect diagnosis. In some cases, this leads to a worsening of the course of NMOSD. We present a case of late diagnosis of NMOSD that confirms the development of exacerbation in the patient 2 months after the first course of therapy with alemtuzumab prescribed as a highly effective therapy for highly active remitting MS. Timely diagnosis of NMOSD makes it possible to exclude such cases.


Asunto(s)
Neuromielitis Óptica , Humanos , Neuromielitis Óptica/diagnóstico , Neuromielitis Óptica/tratamiento farmacológico , Femenino , Adulto , Errores Diagnósticos , Alemtuzumab/uso terapéutico , Autoanticuerpos/sangre , Acuaporina 4/inmunología , Diagnóstico Diferencial , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/tratamiento farmacológico
2.
Artículo en Ruso | MEDLINE | ID: mdl-19459468

RESUMEN

AIM: To study ultrastructural changes of hemolytic and enterohemorrhagic Escherichia coli during interaction with metabolites of Lactobacillus fermentum. MATERIALS AND METHODS: Strains of pathogenic hemolytic (Hly) and enterohemorrhagic Escherichia coli (O157:H7) as well as symbiotic bacteriocinogenic strain Lactobacillus fermentum 97 were used. Inhibition of growth of viable cells was performed by delayed antagonism method. Using electron microscopy, assessment of ultrastructural changes of hemolytic and enterohemorrhagic E. coli under the influence of diffusing in MPC-agar metabolites of lactobacilli. RESULTS: Changes pointing to profound destructive processes in bacterial cells were detected on ultrathin sections. Under the influence of diffusing metabolites of lactobacilli, the following changes were observed: destabilization of cell wall, expansion of periplasmatic space, and emergence of low electron density areas of cytoplasm in polar sections of cells with visualization of floccular material. Emergence of elongated paracrystallic packings and filamentous structures of different length, which deserve special study, was observed in cells of hemolytic E. coli. CONCLUSION: Bacteriocin-like products of lactobacilli during interaction with pathogenic E. coli cause profound destructive changes in the latter which lead to destruction of target cells.


Asunto(s)
Escherichia coli O157/ultraestructura , Limosilactobacillus fermentum/metabolismo , Antibiosis , Bacteriocinas/metabolismo , Escherichia coli O157/patogenicidad , Factores de Hemolisina/metabolismo , Limosilactobacillus fermentum/crecimiento & desarrollo , Microscopía Electrónica
3.
Artículo en Ruso | MEDLINE | ID: mdl-19340962

RESUMEN

Using electron microscopy, ultrastructural organization of microbial parietal biofilm in colon of immunodeficient mice line B10-hr(rhy) was studied before and after peroral inoculation with enteropathogenic strain of Clostridium difficile. It was shown that infection leads to dispersion of normal biofilm in various sites and imbalance in natural proportions of different bacterial associations. Also, clear ultrastructural signs of involution of Gram-negative microorganisms were observed. In the remaining areas of the biofilm, density of bacterial population increased. In the same areas massive intrusion of microorganisms in epitheliocytes occurred with their subsequent localization in phagosomes, phagolysosomes and, in some cases, in the cytoplasm of degenerating eukaryotic cells.


Asunto(s)
Biopelículas , Clostridioides difficile/fisiología , Colon/microbiología , Enterocolitis Seudomembranosa/microbiología , Animales , Adhesión Bacteriana , Colon/ultraestructura , Enterocolitis Seudomembranosa/patología , Enterocitos/microbiología , Enterocitos/patología , Bacterias Gramnegativas/fisiología , Bacterias Gramnegativas/ultraestructura , Ratones , Microscopía Electrónica , Fagosomas/microbiología
4.
Med Parazitol (Mosk) ; (4): 36-41, 1999.
Artículo en Ruso | MEDLINE | ID: mdl-11221003

RESUMEN

Patients with erythematous Ixodes tick-borne relapsing fever were examined and their skin biopsy specimens were morphologically studied to reveal clinical, immunological and morphological features of erythematous Ixodes tick-borne relapsing fever. Two types of development of erythema migrans were identified. These include 1) a typical type that appears as an area of homogenous hyperemia or that of annular shape and 2) an atypical one that presents as minor vesicles. There were elevated serum immunoglobulins A levels at the height of the disease. Morphologically, at the early stage of the disease, the center of erythema shows disturbances characterized by epidermal dystrophic processes, koilocytosis, subhorny and epidermal vesicles. The dermis displays solid perivascular lymphocytic infiltrates admixed with fibroblasts, fibrocytes, macrophages, plasmocytes, eosinophils, degranulated labrocytes. The interstitium exhibits scanty infiltrates. These changes are less pronounced at the periphery. Electron microscopy shows the structures morphologically similar to those of Borrelia. The late stage (days 15-23) of the disease is marked by insignificant dystrophy and perivascular fibrosis. There were no interstitial infiltrates. By and large, the pattern of clinical and immunological manifestations in patients with erythema migrans correlates with dermal morphological changes.


Asunto(s)
Eritema Crónico Migrans/patología , Adolescente , Adulto , Anciano , Eritema Crónico Migrans/inmunología , Humanos , Persona de Mediana Edad , Piel/irrigación sanguínea , Piel/patología
5.
Artículo en Ruso | MEDLINE | ID: mdl-9027169

RESUMEN

As revealed in this study, the macrocolony of Proteus mirabilis, formed on solid culture medium, may consist both of the main part and of sporadically appearing dissociating subcolonies, considerably differing one from another. The outer edge of the main part of the macrocolony of swarming cells is represented by bacteria located in three perpendicular directions. The next intermediate area consisting of two layers is represented by bacteria oriented, as a rule, in one direction. The center of the colony is made up of short microbial cells. Between the upper layer and the surface of agar an original subpopulation of microbial cells, forming a separate layer, has been detected; together they determine the planar sandwich-like architectonics of the macrocolony.


Asunto(s)
Proteus mirabilis/crecimiento & desarrollo , Medios de Cultivo , Humanos , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Mutación , Proteus mirabilis/aislamiento & purificación , Proteus mirabilis/ultraestructura
7.
Acta Virol ; 35(2): 174-86, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1681715

RESUMEN

Electron microscopic examination revealed replication and accumulation of Rickettsia sibirica in the fat body of experimentally infected Dermacentor reticulatus ticks. Rickettsia are released from the fat body cells by budding being surrounded with cytoplasm and plasmalemma of the host cell. Eukaryotic cell structures have been detected consisting of lamella layers whirled around the intact rickettsiae. In addition to rickettsia, microorganisms morphologically resembling Francisella tularensis and an orbivirus were found in tick tissues at morphological examination. The morphology of the virus and stages of its morphogenesis are described. Mixed viral and rickettsial infection has been shown to develop in the same ticks and even in the same fat body cells in a very close association.


Asunto(s)
Vectores Arácnidos/microbiología , Dermacentor/microbiología , Infecciones por Reoviridae/microbiología , Infecciones por Rickettsia/patología , Animales , Vectores Arácnidos/ultraestructura , Dermacentor/ultraestructura , Cuerpo Adiposo/microbiología , Cuerpo Adiposo/ultraestructura , Femenino , Reoviridae/crecimiento & desarrollo , Reoviridae/ultraestructura , Infecciones por Reoviridae/patología , Rickettsia/crecimiento & desarrollo , Rickettsia/ultraestructura , Replicación Viral
8.
Zh Mikrobiol Epidemiol Immunobiol ; (2): 68-72, 1991 Feb.
Artículo en Ruso | MEDLINE | ID: mdl-1867038

RESUMEN

The ultrastructural aspects of the interaction of R. sibirica and R. slovaca with cells of mites of the species Dermacentor reticulatus, D. marginatus and Ixodes ricinus after their parenteral infection, as well as in the organs of D. marginatus infected naturally in the environment, have been studied. Both rickettsial species have similar morphology in different organs of the vector. These rickettsiae not only multiply, their populations are also partly destroyed in phagolysosomes. The natural mixed infection of R. sibirica and orbivirus in cells of D. reticulatus is described. As shown in this study, both associates pass through the complete ontogenetic cycle of development on the level of the host body and also on the level of an individual cell.


Asunto(s)
Rickettsia/ultraestructura , Garrapatas/ultraestructura , Animales , Vectores Arácnidos/microbiología , Vectores Arácnidos/ultraestructura , Checoslovaquia , Dermacentor , Cuerpos de Inclusión Viral/ultraestructura , Virus de Insectos/ultraestructura , Microscopía Electrónica , Virus ARN/ultraestructura , Rickettsia/patogenicidad , Garrapatas/microbiología
9.
Vopr Virusol ; 36(1): 48-53, 1991.
Artículo en Ruso | MEDLINE | ID: mdl-1713373

RESUMEN

A comparative study of surface membranes of human cell J-96 and J-48 cultures with different sensitivity to alpha/beta interferon (IF). Reduced sensitivity of J-41 cells to IF-alpha/beta was found to be accompanied by a loss of highly specific receptors for IF-alpha, the lack of changes in the cell surface structures upon treatment with IF-alpha/beta, reduced intensity of cell fusion upon successive treatment with IF and polyethylene glycol. The results are discussed in connection with the observed changes in the activity of superoxide dismutase in J-96 and J-41 cell lines after treatment with IF.


Asunto(s)
Células Cultivadas/efectos de los fármacos , Interferones/farmacología , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Células Cultivadas/metabolismo , Células Cultivadas/ultraestructura , Resistencia a Medicamentos , Humanos , Interferón Tipo I/metabolismo , Interferones/metabolismo , Microscopía Electrónica , Receptores Inmunológicos/efectos de los fármacos , Receptores Inmunológicos/metabolismo , Receptores de Interferón , Superóxido Dismutasa/metabolismo
11.
Biull Eksp Biol Med ; 110(11): 510-3, 1990 Nov.
Artículo en Ruso | MEDLINE | ID: mdl-1982080

RESUMEN

We have characterized an interaction of 20 strains of Neisseria meningitidis serogroups A, B, C, 29E, W-135 and Z with immobilized fibronectin of human plasma. The adhesion of meningococci to fibronectin was determined by the extent of piliated cells and did not depend on the meningococcal serogroup. Binding of non-piliated or weakly piliated strains (2-5% of piliated cells in the stock) was sufficiently greater than those piliated (8-10%), where the adhesion to fibronectin was not at all observed. The examination of two well-piliated strains showed that the loss of pili resulted in the increase of bacterial adhesion to fibronectin. Constants of association and dissociation of piliated and non-piliated strains to fibronectin were calculated. The role of meningococci-fibronectin interaction in the pathogenesis of meningococcal infection is discussed.


Asunto(s)
Fibronectinas/inmunología , Infecciones Meningocócicas/etiología , Adhesión Bacteriana/efectos de los fármacos , Adhesión Bacteriana/fisiología , Relación Dosis-Respuesta a Droga , Fibronectinas/metabolismo , Fibronectinas/farmacología , Fimbrias Bacterianas/efectos de los fármacos , Fimbrias Bacterianas/metabolismo , Humanos , Técnicas In Vitro , Infecciones Meningocócicas/microbiología , Neisseria meningitidis/clasificación , Neisseria meningitidis/efectos de los fármacos , Neisseria meningitidis/metabolismo , Neisseria meningitidis/patogenicidad , Serotipificación
12.
Mikrobiol Zh (1978) ; 52(4): 17-22, 1990.
Artículo en Ruso | MEDLINE | ID: mdl-2273994

RESUMEN

Transfer of conjugative hybrid plasmid RP4::Mu cts 62 from Escherichia coli into Bac. cereus, Bac. thuringiensis, Bac. mesentericus and Bac. polymyxa cells led to the multiple effects on the structure and physiology of bacillus cells. It has resulted in a decrease of the bacillus vitality, in the accelerated autolytic decay of cells, in the delay of cell growth and reproduction rate in liquid and solid media, in the disruption of ultrastructure of the cell membrane and its surface layer.


Asunto(s)
Bacillus/genética , Plásmidos/genética , Transformación Bacteriana/genética , Bacillus/ultraestructura , Conjugación Genética , Farmacorresistencia Microbiana/genética , Escherichia coli/genética , Microscopía Electrónica
13.
Artículo en Ruso | MEDLINE | ID: mdl-1696768

RESUMEN

R. prowazekii antigens have been tested with the use of monoclonal antibodies (McAb) to different epitopes of the microorganism. As revealed in these tests, McAb B4/4 and A-3/D, active against species-specific thermolabile antigen, interact with protein having a molecular weight of 90-120 KD. McAb C5/2, active against thermostable group antigen common with that of Rickettsia typhi, interact with LPS-like antigen having a molecular weight of 30 KD. Ultrastructural immunochemical studies have revealed that both R. prowazekii antigens are located on surface structures of rickettsiae, such as the microcapsule and cell wall.


Asunto(s)
Anticuerpos Monoclonales , Antígenos Bacterianos/análisis , Rickettsia prowazekii/inmunología , Antígenos de Superficie/análisis , Coxiella/inmunología , Epítopos/inmunología , Técnicas Inmunológicas , Microscopía Electrónica , Peso Molecular , Rickettsia prowazekii/ultraestructura , Rickettsia typhi/inmunología , Especificidad de la Especie
14.
Artículo en Ruso | MEDLINE | ID: mdl-2499144

RESUMEN

The influence of plasmid RP4 Mucts62, heterologous for B. cereus, on the growth rate of B. cereus strains GA 682 and 319 obtained in our earlier experiments and on changes in the ultrastructure of their cell walls in comparison with B. cereus initial strains GP 7 and DSM 318 has been studied. Plasmid RP4 Mucts62 with a wide spectrum of action has been found not only to determine the functional signs of resistance to antibiotics and thermal sensitivity in the heterologous host, but also to take part in the morphological organization of the cell surface structure, and in particular in the structure of the S-layer. B. cereus strains containing plasmid RP4 Mucts62 are characterized by slower growth rate and cell fragility.


Asunto(s)
Bacillus cereus/ultraestructura , Pared Celular/ultraestructura , Plásmidos , Bacillus cereus/genética , Bacillus cereus/crecimiento & desarrollo
15.
Artículo en Ruso | MEDLINE | ID: mdl-2565638

RESUMEN

The adhesive activity of 113 meningococcal strains with different invasive properties and 10 Neisseria nonpathogenic strains have been studied. Adhesive properties have been revealed in 80-82% of these strains. Meningococcal strains isolated from the nasopharynx of carriers possess high hemagglutinating activity. The percentage of cells with pili in these strain was also higher than that in meningococcal strains isolated from the liquor of patients. This shows the presence of direct correlation between the number of pili in the cells (according to the data of electron microscopy) and their activity in the hemagglutination test, which makes it possible to use this test for the determination of the adhesive capacity of meningococci, associated with the presence of pili.


Asunto(s)
Adhesión Bacteriana , Neisseria meningitidis/patogenicidad , Animales , Portador Sano/microbiología , Eritrocitos/inmunología , Fimbrias Bacterianas/inmunología , Fimbrias Bacterianas/ultraestructura , Pruebas de Hemaglutinación/métodos , Humanos , Meningitis Meningocócica/microbiología , Microscopía Electrónica , Neisseria meningitidis/inmunología , Neisseria meningitidis/aislamiento & purificación , Neisseria meningitidis/ultraestructura , Conejos , Virulencia
16.
Tr Inst Im Pastera ; 66: 95-103, 172, 1989.
Artículo en Ruso | MEDLINE | ID: mdl-2485311

RESUMEN

Materials are submitted on electron-microscopic studying of alive and inactivated Coxiella in their interaction with murine cells during 28 days observations. The most variability of Coxiella morphologic types is shown to be found in spleen. The structure of endospora type is described. Several types of phagosomes are revealed and described.


Asunto(s)
Coxiella burnetii/fisiología , Fiebre Q/microbiología , Animales , Coxiella burnetii/ultraestructura , Ratones , Ratones Endogámicos C3H , Microscopía Electrónica
17.
Zh Mikrobiol Epidemiol Immunobiol ; (9): 47-51, 1988 Sep.
Artículo en Ruso | MEDLINE | ID: mdl-3144817

RESUMEN

To study the adhesion of meningococci under the conditions of a monoinfection and mixed infection (in association with influenza virus), the experimental model of mixed influenzal and meningococcal infection has been created in the culture of epithelial cells HEp-2. On this model in increase in the intensity of the adhesion of meningococci to eukaryotic cells, as well as in the intensity of the meningococcal colonization of such cells, after their preliminary infection with influenza virus has been observed. The study has revealed that in mixed infection the adsorption of extracellular virions onto the surface of bacteria occurs. During this adsorption viral processes directly interact with the microcapsule of the meningococcus.


Asunto(s)
Meningitis Meningocócica/microbiología , Neisseria meningitidis/patogenicidad , Adsorción , Adhesión Bacteriana , Células Cultivadas , Epitelio/microbiología , Epitelio/ultraestructura , Humanos , Virus de la Influenza A/patogenicidad , Virus de la Influenza A/ultraestructura , Gripe Humana/microbiología , Gripe Humana/patología , Meningitis Meningocócica/patología , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Neisseria meningitidis/ultraestructura , Virión/patogenicidad , Virión/ultraestructura
18.
Artículo en Ruso | MEDLINE | ID: mdl-3551413

RESUMEN

Specific differences in the structure of colonies and the location of microbial cells in colonies, characteristic for aggregating and nonaggregating genetically related pairs of P. vulgaris and P. mirabilis strains, have been demonstrated by means of transmission and scanning electron microscopy. In calculating the number of flagellae per 100 outlines of microbial bodies revealed in negatively stained preparations, the fact that both aggregating and nonaggregating bacteria possess practically the same number of flagellae, on the average 4-8 flagellae per microbial cell outline, has been established. This fact indicates that the presence of flagellae in microbial cells is unrelated to their capacity for swarming.


Asunto(s)
Proteus mirabilis/ultraestructura , Proteus vulgaris/ultraestructura , Movimiento Celular , Flagelos/ultraestructura , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Mutación , Especificidad de la Especie
19.
Artículo en Ruso | MEDLINE | ID: mdl-2873698

RESUMEN

The study of the use of scanning electron microscopy and the analysis of the initial stages of interaction between S. typhi and eukaryotic cells by the method of three-dimensional reconstruction has revealed that the infective agent penetrates into the cytoplasm on the principle of internalization. The internalization of S. typhi occurs with the active participation of the eukaryotic cells which, at the beginning, envelopes the bacteria with its processes, and the infective agents firmly adhere to the glycocalyx of the host cell by means of special fimbria-like formations differing from fimbriae by their lesser rigidity and thickness; then the microbes fixed to the membrane penetrate inside the cell without destroying its cytoplasmic membrane. Differences in the processes of the interaction of eukaryotic cells with S. typhi initial strain 238 and its variant free from the plasmid with a molecular weight of 6 Md, characterized by its lower capacity for association with cells of continuous cell culture L929, have been revealed. The factors stimulating the ingestion of S. typhi by eukaryotic cells are under study at present.


Asunto(s)
Células L/ultraestructura , Salmonella typhi/ultraestructura , Adhesividad , Animales , Fimbrias Bacterianas/ultraestructura , Células L/microbiología , Ratones , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Salmonella typhi/patogenicidad , Propiedades de Superficie , Factores de Tiempo , Virulencia
20.
Vopr Virusol ; 29(5): 586-9, 1984.
Artículo en Ruso | MEDLINE | ID: mdl-6393583

RESUMEN

The effect of BCG infection of L929 cells on replication of oncovirus type C was studied. Ultrathin sections of the BCG-infected culture were examined electron microscopically 1, 3, 6, 8, and 10 days postinfection. Most microorganisms with the morphology typical of mycobacteria were found inside phagosomes. The number of extracellular virions as well as budding and abnormal forms per one cell contour was counted. BCG-infected cells were found to produce significantly more virus than the controls. The difference was maximal 3 days postinoculation. Possible reasons for the increased oncovirus production by continuous cell lines after infection with BCG are discussed.


Asunto(s)
Células L/microbiología , Mycobacterium bovis/patogenicidad , Retroviridae/fisiología , Animales , Células L/ultraestructura , Lisosomas/microbiología , Lisosomas/ultraestructura , Ratones , Microscopía Electrónica , Mycobacterium bovis/ultraestructura , Fagocitosis , Retroviridae/ultraestructura , Factores de Tiempo , Virión/ultraestructura , Replicación Viral
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