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T G Chanishvili

Publications and source records attributed to T G Chanishvili.

At least 19 recordsLinked to original sources
PubMed1993

[Antibiotic resistance plasmids in various strains of Staphylococcus aureus].

Plasmids with the molecular weights of 1.6 to 21.0 MD were detected in Staphylococcus aureus. The plasmids determined resistance to benzylpenicillin, ampicillin, streptomycin, erythromycin, tetracycline, chloramphenicol, arsenate and arsenite. Strain p16 of Staphylococcus aureus contained plasmid pL16 with the molecular weight of 18.0 MD determining resistance to erythromycin, streptomycin, benzylpenicillin and ampicillin. The plasmid has two replication sites and is likely a natural recombinant of two plasmids.

Drug Resistance, Microbial↗
PubMed1992

[Conjugative R plasmids isolated from hospital strains of Pseudomonas aeruginosa].

It was shown that Pseudomonas aeruginosa hospital strains isolated from patients and environment in the Republican Centre of Burns in Tbilisi contained conjugative R plasmids. The plasmids were marked pM15 and pM19, respectively. The plasmid pM15 determined resistance to carbenicillin, kanamycin and tetracycline and plasmid pM19 determined resistance to carbenicillin, kanamycin, tetracycline, chloramphenicol, gentamicin and streptomycin. Plasmid pM15 had a molecular weight of 45.8 MD and seven sites for EcoRI, six sites for HindIII and five sites for Hpa-I-restrictase. This plasmid, as others, belongs to the Inc-P1 incompatibility group.

Conjugation, Genetic↗
PubMed1992

[Antibiotic sensitivity and pathogenetic factors of hospital strains of Pseudomonas aeruginosa isolated from patients treated in a resuscitation unit].

Strains of Pseudomonas aeruginosa were isolated from patients treated in the Centre of Thermal Affections in 1985-1989. It was shown that 72.9, 59.3, 33.8 and 54.2 per cent of the isolates were sensitive to cefotaxime, tobramycin, gentamicin and polymyxin, respectively. The study of pathogenicity factors of the isolates revealed that 83 per cent of the strains produced thermolabile enterotoxin, 79.6 per cent of the strains had adhesive activity and 71.1 per cent of the strains produced hemolysin. The study detected combinations of various pathogenicity factors. 42.3 per cent of the isolates had both adhesive and enterotoxigenic properties. Adhesiveness and hemolytic activity were shown by 13.5 per cent of the strains. 16.9 per cent of the strains produced both enterotoxin and hemolysin. Adhesive activity, enterotoxigenicity and hemolysin production were observed in 6.7 per cent of the strains. It was noted that the strains of P. aeruginosa resistant to polymyxin mainly produced enterotoxin (18.6 per cent) and those resistant to cefotaxime had adhesive activity (34.0 per cent).

Anti-Bacterial Agents↗
PubMed1992

[The pathogenicity factors of bacteria in the genus Acinetobacter].

Eighty Acinetobacter strains, isolated in Togliatti from patients with purulent inflammatory diseases, were studied to determine their pathogenicity factors. Out of these 80 strains, 32.5% were found to have enterotoxigenic activity and 46.2%, adhesive activity. They were related to adhesins of the human type and to adhesins of the sheep, rabbit, swine and guinea pig types. But the most important phenomenon established in this study was the combination of different pathogenicity factors detected in Acinetobacter bacteria. Analysis of the combination of pathogenicity factors revealed that 7.5% of Acinetobacter strains had adhesive and enterotoxigenic activity, 15.3% of these strains combined adhesive and hemolytic activity and 1.2% of them were found to be enterotoxigenic and hemolytic. Only 5.0% of Acinetobacter strains were found to carry all there pathogenicity factors simultaneously.

Acinetobacter↗
PubMed1991

Host-controlled modification and restriction as a criterion of evaluating the therapeutical potential of Pseudomonas phage.

The recently isolated phages phi ST3 and phi ST1 were compared as to their lysis behaviour in about 100 different P. aeruginosa strains. The growth of phi ST3 varies greatly in different host strains. We demonstrated one case of "non-classical", host-dependent modification and restriction. Here the capability to adsorb, and consequently to reproduce in a given host strain differs, depending on which modification the phage acquired in its former host. The DNA-containing phage phi ST1 displays stable lysis properties in the majority of the host strains. This makes phi ST1 a candidate for therapeutic phage preparations. One of the reasons for stable lysis properties is the apparent selection against recognition sites of restriction enzymes in its genome.

Bacteriophages↗
PubMed1991

[New systems of host specificity of DNA Pae 610 and Pae 603].

In order to find new systems of host specificity (SHS), wide screening among different strains of Ps. aeruginosa was carried out. By means of cross-titration of phages BT and FP-series two new systems of modification-restriction were identified: Pae 610 and Pae 603. They differ from the known system of host specificity Pae R7.

Anti-Bacterial Agents↗
PubMed1990

The virulent bacteriophage IRA of Salmonella typhimurium: cloning of phage genes which are potentially lethal for the host cell.

Morphological and biological properties of Salmonella typhimurium phage IRA were studied. The phage is a member of the Styloviridae family and exhibits a very wide spectrum of lytic activity. Molecular cloning of phage genes whose expression is lethal for the host cell has been performed and consequences of gene expression have been investigated. Expression of recombinant plasmid pKI71 causes structural changes of the cell wall and also degradation of host DNA while plasmid DNA remains intact. Expression of pKI72 blocks normal cell division. The possibility of applying such recombinant clones in marking pathways of microbial contamination in water areas is proposed.

Bacteriolysis↗
PubMed1988

[Experimental study of the interaction of phages and bacteria in the environment].

For the first time the possibility of the interaction of phages and bacterial cells in the environment, consisting in the adsorption and subsequent replication of viral particles, has been shown. The data obtained in this investigation provide grounds for using phages in the environment. Experiments with Escherichia coli M-17 and phage FM17, carried out on experimental models, have demonstrated that the use of phages in the environment completely prevents the realization of the transfer of enteral infections through everyday contacts and the contamination of children and adults under hospital conditions.

Coliphages↗
PubMed1987

[Modelling of the epidemic process of suppurative septic infections using a Pseudomonas aeruginosa bacteriophage].

The method for modeling the epidemic process of pyoseptic infections with the use of P. aeruginosa bacteriophage is proposed. The application of this method in urological and traumatological wards has made it possible to confirm the role of patients as the sources of infection and the part played by instruments and the hands of the medical personnel in its transfer.

Bacteriophages↗
PubMed1987

[Morphological changes in the liver cells of rabbits with a bacterial infection].

In the process of bacterial infection in rabbits, their livers have been studied by means of light and electron microscopy, as well as by morphometric analysis. The results evidence pathomorphologic and ultrastructural changes occurring in liver cells. These changes, probably, cause different metabolic disturbances and thus facilitate the development of destructive processes in vital organs.

Animals↗
PubMed1987

[Changes in the functional activity of the liver cells in rabbits during a bacterial infection].

In the process of the development of bacterial infections, the activity of marker enzymes in the membrane structure of liver cells has been studied in rabbits by biochemical and electron-histochemical methods. The results of these studies have shown that, simultaneously with the progressing course of cell pathology and inhibition of the function of mitochondria, microsomes and peroxisomes, the lysosomes activate for the realization of the protective function formed in the course of evolution. At the same time the excessive labilization of lysosomal membranes facilitates the development of cell pathology, which is confirmed by the accumulation of residual bodies in the cytoplasm.

Animals↗
PubMed1986

[Purification and properties of staphylococcal hyaluronidase].

Microbial hyaluronidase (EC 4.2.2.1) was isolated from the culture fluid of Staphylococcus aureus 0-15 with purification by precipitation with 1 volume of ethyl alcohol, chromatography on DEAE cellulose and ultrafiltration through DA type membranes with the pore size of 0.65 micron ("Millipore") and PM-10 membranes ("Amicon"). The specific activity of the enzyme averaged to 2700 turbidimetric units or 32130 IU. 6585-fold purification of the enzyme was performed. The optimum action on hyaluronic acid was observed at pH 5.0-6.5. Hyaluronidase was inhibited by Fe3+, Fe2+ and Cu2+, activated by Ca2+ and stabilized by 0.15 M NaCl. It was detected that the enzyme had two molecular forms with the isoelectric points of 5.4 and 6.5 and the molecular weights of 55 000 and 24 0000 D respectively. The glycoprotein nature of the enzyme was shown. The immobilized form of hyaluronidase on activated polyglucin, a soluble biocompatible polymer was prepared. The form is characterized by higher thermostability.

Chromatography, DEAE-Cellulose↗
PubMed1985

[Two types of structural organization of double-stranded DNA in phage particles].

Structural arrangement of linear unmodified duplex DNA in phage particles FI5 and SB1 was studied by the techniques of absorption spectrum, CD, scanning microcalorimetry. Hyperchromism is not registered for SB1 DNA in situ at 260 nm, in contrast to FI5 and other phages, but is visible at 260-290 nm. Phage SB1 had an unusual CD spectrum: intensity of the positive band at 280 nm was, practically, identical to the free SB1 DNA intensity. However, the character of SB1 DNA in situ melting in 1.5% HCHO corresponds to FI5 (and other phages) melting in situ in the presence of HCHO. Analysis of these spectral studies and calorimetry permitted one to identify the peaks on the thermograms of phages FI5 and SB1. Variability of heat capacity in the zone of phage particles destruction is supposed to be connected with DNA rearrangements.

Calorimetry↗
PubMed1985

[Role of lysosomes during the development of a fibroblast staphylococcal infection].

The study of staphylococcal infection in chick embryo fibroblasts, carried out by electron-histochemical and morphometric methods, has revealed the presence of correlation between the degree of fibroblast destruction and the permeability of lysosomal membranes. The development of bacterial infection, depending on the presence of homologous bacteriophages in the medium, has also been studied.

Animals↗
PubMed1984

[Fibroblast phosphatase activity in the staphylococcal infection process].

The study of the phosphatase activity of chick fibroblasts in the process of staphylococcal infection by the electron-histochemical method has revealed the presence of correlation between the degree of cytoplasmic destruction in fibroblasts and the level of acid phosphatase activity. Changes in the phosphatase activity of fibroblasts in the process of bacterial infection, depending on the presence of homologous bacteriophages in the system used as a model, have also been studied.

Acid Phosphatase↗
PubMed1982

[Pseudomonas aeruginosa bacteriophages isolated in a surgical hospital].

New data on P. aeruginosa bacteriophages isolated from patients, as well as from washings obtained from various objects, in a surgical hospital are presented. 14 pure strains of P. aeruginosa bacteriophages have been isolated from 90 specimens of the material under study. The morphology of the colonies, the titer and the spectrum of action of the phages are characterized. The spectrum of action of polyvalent combination obtained by the mechanical mixture of different phages has been studied. The most active phages have been found to lyse 71.1, 63.1, 59.2 and 41.8 per cent of P. aeruginosa museum strains (225 strains).

Bacteriophages↗