PubMed Health⌕ Search

Biomedical subjects

M Coşman

Publications and source records attributed to M Coşman.

14 recordsLinked to original sources
PubMed1976

Restriction and modification of typing phages by an R factor in S. typhi.

We have investigated the qualities of one R factor 552 discovered on a strain of S. typhi resistant to A, C, S, T, nontypable, isolated from stool cultures; from the same patient, before starting the treatment we isolated, from his blood sample, the strain S. typhi 221, sensitive to A, C, T, degraded phage-type Vi A. Factor R 552 fi- when infecting strains of S. typhi Vi A and of A degraded 221- leads to the conversion of the respective phage-types into non-typable ones, as a result of the restricting and modifying effect on phage Vi A and on the derivatives resulting from it. Derivative R 552-1 as a resistance marker to ampicilline has a restrictive effect on the phage of S. panama A 47 too. Not taking into account possible causes such as spontaneous mutation, lysogeny, and adsorption of phages, we reach for the conclusion that R factor 552, through is restrictive effect, is the only cause responsible for the existence in the same patient of two strains of S. typhi different from the point of view of phage-type and antibiotype.

Bacteriophage Typing↗
PubMedDate not supplied

Salmonella serotype typhimurium phage typing. A critical evaluation.

Of 12,930 Salmonella serotype typhimurium strains, phage typed during 1985-1988, 45.68% were "nontypable" by Anderson's set; the percent of typable strains decreased from 54.17 in 1986 to 30.54 in 1988. Of 90 phage patterns of sensitivity, 22 were currently encountered. Phage types 1, 18 and 104 were most frequent to strain of both human and non-human origin. In food generating S. typhimurium outbreaks, phage types 1 and 36 were prevalent. Except lysotypes 198 and 95, isolated from "single cases" in man only, all other phage types were common in man and animals, too. Introducing other typing methods to serotype typhimurium "nontypable" strains (by Anderson's set) was considered necessary for epidemiological purposes.

Animals↗
PubMedDate not supplied

[Sensitivity to antibiotics and chemotherapeutic agents in some strains of Salmonella typhi isolated in Romania during the period 1974-1976].

Investigations were carried out on 781 S. typhi strains isolated from patients and carriers. Testing of the sensitivity to chemotherapeutical agents by diffusiometry and the incorporation technique led to the detection of four resistant strains: 1 strain isolated by coproculture from a carrier since 1958, resistant to A, K, N, Ca and Cf and 3 strains isolated by coproculture, biliculture and uroculture from a carrier since 1974, resistant to A and Ca. The R factors of these strains were transferred in their totality. The resistant strains did not manifest any particular pathogenicity for the laboratory animal, and their immunogenic potential was below that of the current typhoid vaccine. None of the 781S typhi were resistant to Cmx, C, G, T, Co and Po. Consequently, in Romania Chloramphenicol may be used in continuation in the treatment of typhoid fever, and Cotrimoxazol, Gentamycin, Tetracyclin and Ampicillin are and remain reserve substitutes. The possible unexpected appearance of resistant S. typhi strains demand, however, further control of the sensitivity to chemotherapeutics of all the isolated strains.

Anti-Bacterial Agents↗
PubMedDate not supplied

[Additional anti-Klebsiella phages used in lysotyping of Klebsiella strains].

In order to increase the efficiency of lysotyping as a method for differentiating Klebsiella strains the authors tested the activity of 10 additional phages isolated, prepared and studied in the laboratory and compared to the Slopek-Milch set. A number of 734 Klebsiella strains were isolated in different clinical and epidemiological conditions and lysotyped. The phage type was determined in 64.60% of the strains examined, using 15 phages of the Slopek-Milch set. By using additional autochtonous phages the proportion of lysotypable strains reached 77.80%; therefore, 13.20% were sensitive only to the additional phages.

Bacteriophage Typing↗