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N S Smirnova

Publications and source records attributed to N S Smirnova.

31 records · Page 2Linked to original sources
PubMed1986

Peculiarities of Rickettsia prowazekii in the cell culture as revealed by cryoultramicrotomy.

Ultrastructure of Rickettsia prowazekii has been followed in L-929 cells 4 days post-infection (p.i.) by cryoultramicrotomy. Groups of rickettsiae were present in the cytoplasm outside of vacuoles forming microcolonies. The size of rickettsiae amounted to 400 X 700 nm, the average thickness of the cell wall was 5 nm, that of periplasmic space and cytoplasmic membrane 14 and 6 nm, respectively. Within intracytoplasmic colonies the rickettsiae were tightly packed and their cell walls were closely adjacent to each other. No halo or capsule-like coating around them was detected. No ultrastructural details were observed in the light translucent spaces between cells. Marginal rickettsiae of the microcolonies were often in close contact with the host cell mitochondria.

Animals↗
PubMed1986

Ultrastructure of Rickettsia sibirica during interaction with the host cell.

Rickettsia sibirica (strain Netsvetaev) was found within large translucent spaces in the cytoplasm of L-929 cell monolayer cultures on day 6 postinfection (p.i.). These rickettsiae were rod shaped 0.3 X 10 microns in size encircled by a halo of up to 200 nm wide corresponding to a capsule-like coat. Directly on the cell wall was a 12 nm thick microcapsule in which subunit structures with 12 nm thick spacing could be recognized. The cell wall membrane was 14 nm thick with a wider internal layer occasionally in a section found split into two electron-dense lamels; the internal layer corresponded to peptidoglycan. The periplasmic space with an average thickness of 5 nm separated the cell wall from a 7 nm thick cytoplasmic membrane. The ultrastructure of R. sibirica was similar to that of other rickettsiae, although the capsule-like coat was thicker than in spotted fever (SF) group rickettsiae.

Animals↗
PubMed1982

[Ultrastructural localization of type-specific antigen of legionella pneumophila].

Cell suspensions of Legionella pneumophila, a virulent Philadelphia I strain, were incubated with rabbit antiserum to type-specific heat-sensitive antigen III having toxic properties with the use of the indirect immunoferritin technique. Antigen III was localized in the outer fibrillar microcapsule-like layer 12-20 mm thick. In the direct immunoperoxidase test antigen III had globular localization on the cell wall surface. The layer described is unlikely to be a true microcapsule, since it does not contain acid mucopolysaccharides and is readily removed from the cell. It is more likely that it forms as a result of antigen III secretion (and, possibly, of other antigens) being more similar to a capsule-like or mucilagenous layer.

Antigens, Bacterial↗
PubMed1979

[Serotype characteristics of clinical strains of Pseudomonas aeruginosa].

A total of 348 P. aeroginosa strains isolated from patients with pulmonary and pleural diseases were studied, and 87% of the test showed the possibility of their serotyping with the use of group-specific agglutinating antisera. Serogroups II, III, IV were found to be prevalent among the strains isolated from patients with bronchopulmonary pathological states. Correlations between definite groups of P. aeroginosa in their sensitivity to antibiotics were established; thus, the cultures belonging the serogroups II, III, IV were found to be more sensitive to tetracycline annd chloramphenicol than the culture belonging to other serogroups.

Anti-Bacterial Agents↗