[Klebsiella pneumoniae adhesion to epithelioid cells in vitro]. / Adgeziia Klebsiella pneumoniae na épitelioidnykh kletkakh in vitro.

The adhesion of K. pneumoniae K24 capsular strain No. 6723 onto subcultured epithelioid human kidney cells RN was studied overtime by light microscopy and by transmission and scanning electron microscopy. To find out the bacterial capsule and glycocalyx of epithelioid cells, the method of staining the samples with ruthenium red was used, this stain producing the coloration of extracellular acidic mucopolusaccharides . The bacteria were found to attach to the qlycocalyx of epithelioid cells by means of protruding areas on the capsule which retained its form and size after both stabilization with ruthenium red and standard glutar -osmium fixation. Under the action of the bacteria epithelioid cells were found to round off, become longer and increase the number of processes. At the sites of contact with the bacteria specific short cytoplasmic processes serving for the attachment of K. pneumoniae cells were discovered.

[Influence of hemolytic plasmids on the development of the "killing" effect in various species of enterobacteria]. / Vliianie gemoliticheskikh plazmid na razvitie "b'iushchego" éffekta u énterobakterií raznykh vidov.

Experiments on isogenic strains of different enterobacterial species, both carrying hemolytic plasmids and free from them, have demonstrated that their "killing" effect on mice is linked with the yield of hemolysin and does not depend on the origin of Hly plasmids or the chemotype of bacteria. Plasmid p IE 567 coding the synthesis of alpha-hemolysin has been shown to be capable of expression in Enterobacter aerogenes, Hafnia alvei and Salmonella typhimurium strains, but E. aerogenes 3/43, H. alvei alpha 773 and Escherichia coli J53 carrying p IE 567, in contrast to E. coli P 678 and S. typhimurium 415 carrying the same plasmid, produce less alpha-hemolysin and have no pronounced effect in reducing the survival time of intranasally infected mice.

[Electron microscopic study of the interaction of nephritogenic strains of Escherichia coli carrying D-mannose-resistant fimbriae with the cells of a human kidney line]. / Elektronno-mikroskopicheskoe izuchenie vzaimodeistviia nefritogennykh shtammov Escherichia coli, nesushchikh D-mannozorezistentnye fimbrii, s kletkami linii pochek cheloveka.

The electron-microscopic study revealed that nephritogenic E. coli having L-mannose-resistant fimbriae contacted with subcultured human renal cells due to the interaction of fimbriae with microvilli and, less frequently, with the cytoplasmic membrane surrounding the main part of the cell, as well as with the electron-opaque fibrillar material in the intercellular space. The possibility of very close interaction was demonstrated; in some cases this interaction was so close that the outlines of bacterial and epitheloid cells followed each other, the invagination of the external membrane of the host cell being sometimes observed. The expediency of using ruthenium red for detecting fimbriae in morphological studies was shown. The cytopathogenic effect observed in this study and developing by the end of the 5-hour period from the moment of the inoculation of the monolayer with E. coli was manifested by the swelling of mitochondria accompanied by the partial ruptures of cristae, the widening of channels in the endoplasmic reticulum, the appearance of the secondary lysosomes and the increase of their number.

[Characteristics of Proteus, Klebsiella, Enterobacter and Citrobacter strains isolated in urological infections]. / Kharakteristika shtammov rodov Proteus, Klebsiella, Enterobacter i Citrobacter, vydelennykh pri uroinfektsiiakh.

The comparative study of more than 300 Proteus, Klebsiella, Enterobacter and Citrobacter strains isolated from patients with urological infections and parenteral infections of other localization, as well as from the feces of healthy persons has been carried out. The strains causing inflammatory processes in the urinary tract have been shown to possess no strict specificity. The ability of opportunistic enterobacteria to cause urinary tract lesions is their polydeterminant property ensured by the combination of different factors. A number of characteristics which can be considered as the markers of "nephritogenic" strains have been revealed. Thus, among Proteus mirabilis strains the largest percentage is constituted by strains fermenting sucrose and producing hemolysin. The urological pathogenicity of "nephritogenic" strains belonging to the genera Proteus, Klebsiella and Enterobacter has been found to be linked with their resistance to complement and their capacity for producing substances increasing capillary permeability. In C. freundii strains differences in O serogroups and a number of markers (the fermentation of raffinose, the formation of hemolysin and permeability factor) have been revealed. These data may be useful for the prognosis and evaluation of the course of urological infections.

[Antibiotic resistance of uropathogenic strains of E. coli isolated from patients in the USSR and the People's Republic of Bulgaria]. / Antibiotikorezistentnost' uropatogennykh shtammov E. coli, vydelennykh ot bol'nykh v SSSR i NRB.

The MIC of benzylpenicillin, ampicillin, ceporin, streptomycin, kanamycin, gentamicin, tetracycline, rondomycin, rifampicin, chloramphenicol, nalidixic acid, orafuran, furacin and furazolidon with respect to E. coli strains isolated from urological patients were determined and compared with those isolated from patients with other localization of inflammatory processes and the feces of healthy persons. It was shown that the strains isolated from the urine of the urological patients were characterized by higher levels of the drug resistance and as a rule were polyresistant. The bacterial resistance was due to the presence of conjugative R plasmids in 26-32 per cent of the cases and nonconjugative R plasmids in 37-38 per cent of the cases. The total number of the cultures with the drug resistance controlled by the plasmid markers amounted to 64-69 per cent. Ceporin, gentamicin, and furacin had the highest inhibitory effect.

[Significance of the ability of E. coli to alter capillary permeability for the reproduction of pyelonephritis in mice]. / Znachenie sposobnosti E. coli izmeniat' pronitsaemost' kapilliarov dlia vosproizvedeniia pielonefrita u myshei.

Experiments in a number of biological models showed that the cultures of E. coli isolated from the urine of children with pyelonephritis had a varied spectrum of pathogenic properties. Histologically confirmed pyelonephritis induced by intravenous infection in CBA mice, treated with 5% glucose by the method of Montgomerie et al., correlated with the bacterial adhesiveness to the epithelium and the interference with capillary permeability, registered in experiments on the pulmonary model with Evans blue used for control. The criterion for the development of pyelonephritis in mice, which was based, in the opinion of Mintogemerie et al., on the positive results, indicating the presence of the infecting agent in the culture obtained by inoculation with the samples of urine and kidney tissue, was found to be insufficient, as only 28 out of 45 cultures of E. coli isolated from the kidneys coincided with histologically confirmed cases of pyelonephritis.