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M L Khatenever

Publications and source records attributed to M L Khatenever.

At least 19 recordsLinked to original sources

[Phage typing of the coagulase-positive staphylococci isolated from various species of animals].

More than 200 coagulase-positive strains of animal origin have been studied by means of Staphylococcus aureus typing phages, belonging to two international sets and intended for typing staphylococci isolated from large cattle and humans, and experimental "chicken" phage A 1591. Among S. aureus strains the cultures isolated from swine, cows, chickens, and belonging to biotypes B1, C1, B2, respectively, have been mostly (in 78.5-90.0% of cases) determined by phage typing. The strains belonging to one biotype have proved to be sensitive predominantly to the same phages. In this connection further differentiation of staphylococci within individual biotypes by means of the phages used in these experiments seems to be impracticable. S. intermedius strains have been found to be completely resistant to the above phages, which confirms that S. intermedius is rightly considered to be an independent species of coagulase-positive staphylococci.

Animals↗

[Classification and biological characteristics of coagulase-positive Staphylococci isolated from animals].

A total of 165 coagulase-positive staphylococcal strains of different origin (142 S. aureus strains and 23 S. intermedius strains) were subjected to biological typing in accordance with the schemes of Hajek-Marsalek and Meyer-Witte. The former of these schemes permitted to identify 68% and the latter 18% of S. aureus strains. The cultures isolated from swine and chickens had the most uniform composition: 85-86% of the strains belonged to biotype B. 44% of the strains isolated from cows and sheep belonged to biotypes C (ecovars bovis and ovis) and A (ecovar hominis); the rest of the strains could not be identified. 96% of the strains isolated from minks were made up of S. intermedius, more than a half of them belonging to biotype E (ecovar canis). In 80% of S. aureus strains and 48% S. intermedius cultures protein A was detected. Only 9% of S. aureus strains of animal origin were found capable of producing enterotoxins (A-D). The expediency of working out a unified scheme for the biotyping of coagulase-positive staphylococci is discussed.

Animals↗

[Coagulase-negative Staphylococci isolated from patients. III. Phage typing].

Coagulase-negative staphylococci of clinical origin were subjected to phage typing by means of phages from the experimental Dutch (Verhoef) and American (Paris) sets. These sets of phages were used to study 153 and 378 strains, respectively. The Dutch phages could lyse 30.1%, and the American ones 19.6% of the cultures. The strains belonging to the species S. epidermidis were lysed in 34.3% and 32.4% of cases, respectively, which is indicative of the fact that the American phages possess a more pronounced specificity in respect to S. epidermidis. The unsufficient effectiveness of typing phages does not yet allow one to evaluate the outlook for the method of phage typing in the study of coagulase-negative staphylococci.

Bacteriophage Typing↗

[Resistance to antibiotics and heavy metal salts of coagulase-positive staphylococci belonging to different biological types (ecovars)].

A total of 189 strains of S. aureus isolated from cows, sheep, swines, poultry, monkeys, rabbits, foxes, and humans and 23 strains of S. intermedius isolated from minks and sables were studied. The staphylococci belonged to different biological types (according to the Hajek-Marsalek's scheme) and ecovars (according to the Meyer-Witte's scheme). The strains were studied with respect to their resistance to 10 antibiotics (benzylpenicillin, streptomycin, tetracycline, levomycetin, erythromycin, oleandomycin, neomycin, kanamycin, monomycin, and novobiocin), mercuric chloride and cadmium sulfate. As a whole the frequency of resistance to the above preparations among the staphylococci of the animal origin was not high. Differences in the frequency and range of the resistance between strains belonging to different biological types (ecovars) were shown. The highest number of the resistant cultures was detected among the strains of the biological type E (ecovar canis) and atypical strains of S. intermedius isolated from the minks. The least number of the resistant cultures was detected among the strains of the biological type C1 (ecovar bovis) isolated from the cows. It was found that almost all strains of S. intermedius were resistant to cadmium sulfate. This may be used as an additional characteristic of the species.

Anti-Bacterial Agents↗

[Coagulase-negative staphylococci isolated from patients. I. Biological properties and biotyping of the strains].

A total of 403 coagulase- and DNAase-negative staphylococcal strains isolated from patients with conjunctivitis, urological diseases, purulent inflammatory processes, septicemia, infected traumas, pyodermia were investigated in 18 biological tests. In a vast majority of cases the absence of correlation between the individual biological characteristics of the strains was revealed. The identification of S. epidermidis and S. saprophyticus, carried out by Akatov et al. in accordance with the schemes of the International Subcommittee, Digranes and Oeding, allowed to determine the species the organisms under test belonged to in 26%, 38% and 64% of the strains, respectively. Most of the identified strains belonged to S. epidermidis. Their biological typing by the methods of Baird-Parker and Akatov-Khatenever allowed the biotype to be determined in 79% and 69% of the cultures. Strains belonging to biotype 1 according to Baird-Peter were most frequently isolated in conjunctivitis, purulent processes and pyodermia, while strains belonging to biotype 2 according to Akatov-Khatenever were prevalent in urological diseases.

Coagulase↗

[Coagulase-negative staphylococci isolated from patients. II. Species diversity of the strains].

Of 403 coagulase-negative staphylococcal strains isolated from patients with different forms of infection 68,1% of the cultures could be identified in accordance with the scheme proposed by Akatov and Devriese. Of these, S. epidermidis constituted 55.1%, S. saprophyticus 13.5%, S. sciuri, S. warneri, S. cohnii, etc., 0.4% to 5.5%. A small group (8,2%) of novobiocin-resistant S. epidermidis and S. hominis strains was detected. S. epidermidis and S. warneri were isolated mostly in septicemia, conjunctivitis, purulent processes; S. saprophyticus and S. sciuri from infected wounds, nonidentified Staphylococcus spp., group I, in urological diseases. The cultures of S. epidermidis sensu stricto belonged, as a rule, to biotype 1, S. epidermidis according to Baird-Parker, S. hominis and S. stimulans belonged to biotype 4. No strains of biotype 2 were detected.

Coagulase↗

[Addition to the scheme of ecologic variants of Staphylococcus aureus].

Altogether 55 S. aureus strains were isolated from the nose and skin of 2 monkey species (Cercopithecus sabaeus and Macaca fascicularis). The strains were studied in 19 biological tests. 45 of these strains were found to differ in their biological properties from the ecological S. aureus variants described in literature. Of these grounds the strains were classified with the new ecovar simiae comprising 2 subvariants. The strains of the ecovar simiae coagulated human plasma, did not coagulate bovine plasma, formed type A/B colonies on a medium containing crystalline violet, required longer time to ferment mannitol (4-5 days), possessed DNase, were sensitive to "human" and resistant to "bovine" phages. The cultures of subvariant 1 produced fibrinolysin and caused type A hemolysis, the strains of subvariant 2 has no fibrinolysin and caused types B and C hemolysis.

Animals↗

[Classification of coagulase-negative staphylococci isolated from urologic diseases].

A total of 174 strains of coagulase-negative staphylococci were isolated from the urine of urological patients in the USSR (Moscow) and the GDR (Wernigerode). Three schemes were used for identifying the species of the cultures (S. epidermidis and S. saprophyticus): the scheme proposed by the International Subcommittee for Taxonomy of Staphylococci and Micrococci (1976), the scheme of Digranes and Oeding (1975) and the scheme proposed by the authors of the present work. The use of the above-mentioned schemes allowed to identify 25, 33 and 68 per cent of the strains respectively. S. epidermidis prevailed among the "urological" staphylococci isolated in Moscow, and S. saprophyticus prevailed among the staphylococci isolated in Wernigerode. The insufficient effectiveness of the existing schemes for identifying the species of coagulase-negative staphylococci and the necessity of searching for new reliable biological tests are emphasized.

Coagulase↗

[Distribution of enterotoxinogenic strains among Staphylococcus aureus isolated from various sources].

A total of 406 S. aureus strains isolated from wound and mammal secretions in patients with wound infections and mastitis, from the throat of healthy children and those with respiratory disease, as well as during an outbreak of alimentary toxicoinfection, were studied. The capacity of these strains for the production of enterotoxins A, B, C, D, E, as well as the phage groups and phage types of these strains were determined. 34.2% of the strains were enterotoxigenic; the occurrence of this characteristic in staphylococci did not depend on the source of their isolation, but correlated with the results of their phage typing. Enterotoxigenic strains were detected most frequently (56.5--68.0%) in phage groups III, I/III and among staphylococci lyzed by additional phages (Nos. 88--96). Almost half of these strains produced enterotoxin A, each of other enterotoxins was produced by 12--14% of the strains. The isolated from the patients were found to produce mostly enterotoxins A and D, and those from healthy persons B and C. The relatively frequent production of enterotoxin D was found to be characteristic of staphylococci belonging to epidemic phagotype 80/81 isolated in mastitis.

Adult↗

[Phage typing and lysogen typing of Staphylococcus aureus].

A comparison was made between the results of phage and lysogenic typing of S. aureus strains isolated during several outbreaks of staphylococcal infection and S. aureus cultures isolated from the same carriers at different periods. The study of the groups of strains having the same origin showed that the differences in the number of reactions were more pronounced in lysogenic typing than in phage typing. For this reason lysogenic typing can be recommended only for the identification of those strains which cannot be identified with the use of the phages of the International Basic Set. The results of the experiments with induced phages proliferating in a restriction-defective strain indicated that restriction and modification were mainly responsible for the specificity of lytic reactions.

Animals↗

[Transfer of drug resistance plasmids from Staphylococcus epidermidis to Staphylococcus aureus in mixed culture].

A possibility of transfer of chloramphenicol-resistance and penicillin-resistance plasmids from 4 different donor S. epidermidis strains to 2 S. aureus strains was demonstrated. Chloramphenocol-resistance plasmid was found in S. epidermidis 1065/77 which was not expressed in this strain but could be transferred to and was expressed in Staphylococcus aureus strains. Penicillin-resistance and chloramphenicol-resistance plasmids were transferred simultaneously in 40 per cent of the colonies.

Chloramphenicol↗

[Drug resistance of hospital strains of Staphylococcus epidermidis belonging to different biological types].

A total of 567 strains of Staph. epidermidis isolated from the bacteria carriers in several surgical units were studied. The cultures were typed according to the method developed by the authors. Their resistance to 12 antibiotics, mercuric chloride and cadmium sulphate was determined. Comparison of the strain biotypes and their drug resistance showed in some cases statistically significant correlation. It should be especially noted that staphylococci with pronounced polyresistance (simultaneous resistance to 7--12 antibiotics) prevailed among the strains belonging to biotypes 1 and 3.

Carrier State↗

[Spontaneous mutants of S. aureus 209 P resistant to 3,6-diaminoacridines].

Spontaneous mutants of S. aureus 209 P resistant to proflavine sulphate and possessing cross resistance to acriflavine and acridine yellow were isolated. Sensitivity of these mutants to acridine orange, acridines No. 40 and 56 remained unchanged. The phage type and the indices of potential pathogenicity of proflavine-resistant mutants coincided with the corresponding S. aureus 209 P indices.

Acridines↗

[Capsule formation in Staphylococcus aureus of hospital origin].

The authors elaborated suitable conditions for cultivation of freshly isolated Staph. aureus, which offered a possibility of detection among them of a high percentage (75.2) of capsular cultures. It was shown that when grown in serum semifluid agar capsular staphylococci formed diffuse colonies of three different types. No correlation between the presence of the capsule, on the one hand, and the absence of the flocculus-forming factor and resistance to the type bacteriophage, on the other hand, was revealed in the Staph. aureus strains.

Cell Wall↗

[Data on the identification of staphylococci of hospital origin. Report 2. Method of biological typing of S. epidermis].

In accordance with the principles of numerical taxonomy the authors elaborated a new method of biological typing of S. epidermidis strains of hospital origin based on the use of 5 tests (gelatinase, hemolysis, lecithinase, phosphatase, lysozyme). The suggested scheme includes 5 biotypes. In typing 690 S. epidermidis strains it was revealed that 47.5% belonged to biotype 1,14.4% - to type 2,11.2% - to type 3,7.7% - to type 4,14.5% - to type 5, and 4.7% were nontyping strains. The suggested scheme permitted better differentiation of the cultures under study than methods of biological typing suggested earlier by foreign authors. The new scheme requires wide approbation.

Bacteriological Techniques↗