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Biomedical subjects

B Skalka

Publications and source records attributed to B Skalka.

46 records · Page 3Linked to original sources

Lethal effect of CAMP-factor and UBERIS-factor--a new finding about diffusible exosubstances of streptococcus agalactiae and Streptococcus uberis.

CAMP-factor, the exosubstance of Streptococcus agalactiae, and UBERIS-factor, the exosubstance of Streptococcus uberis, exerted lethal effect when administered parenterally to rabbits and white mice. A single intravenous dosis of 1,500 activity units per 1 kg body weight resulted in rapid death of the rabbits. To kill mice, the intravenous or intraperitoneal dosis had to be 45 times higher in relation to the body mass. After formaldehyde treatment, both streptococcal exosubstances were deprived of their lethal effect as well as of their synergistic hemolytic activity with the staphylococcal beta-toxin.

Animals↗

Biotyping and determination of protein A in Staphylococcus aureus strain of skin origin.

By means of biotyping we have investigated 150 strains of Staphylococcus aureus isolated from people with dermatologic complaints. We have used six main and three additional biotyping tests. The strains under investigation did not form a closed biotype, on the contrary, they showed a certain biotype plurality. The determination of protein A in 150 strains of S. aureus isolated from dermatologic process of men, 15 strains of S. aureus of bovine origin and 50 strains of Staphylococcus with negative coagulase activity have brought the following results: all strains of S. aureus of skin origin (human strains) contain protein A in various quantities keeping within 2-64 U. Only 2 from 15 s. aureus strains of bovine origin contain protein A and there were none in 50 strains of Staphylococcus with a negative coagulase reaction.

Acetoin↗

Diagnostic utilization of hemolytically active exosubstances of certain Gram-positive bacteria. II. Detection of staphylococcal hemolysins by means of a pre-purified hemolytically active exosubstance of Corynebacterium pseudotuberculosis.

The use of Corynebacterium pseudotuberculosis or of its hemolytically active exosubstance for the detection of staphylococcal hemolysins represents a suitable alterative to the use of the beta-toxin producing strain of Staphylococcus aureus, or of isolated beta-toxin. An increased capture of beta-toxin production was recorded when the CAMP-factor of Streptococcus agalactiae was used. A total of 446 Staphylococcus aureus strains and 48 coagulase-negative staphylococal strains were tested against the prepurified form of hemolytically active exosubstance of Corynebacterium pseudotuberculosis and against the CAMP-factor. The results obtained are in agreement with the testing by means of staphylococcal beta-toxin and of the CAMP-factor. The two modifications of the method for the detection of staphylococcal hemolysins using one plate as proposed by the authors give good results. Their ability of assessment, however, is higher by one degree when the exocubstance of Corynebacterium pseudotuberculosis is employed.

Bacterial Toxins↗

Diagnostic utilization of hemolytically active exosubstances of certain gram-positive bacteria. I. Detection of staphylococcal hemolysins with prepurified preparations of staphylococcal beta-toxin and CAMP-factor of Streptococcus agalactiae.

The authors have modified the one-plate method for the detection of staphylococcal hemolysins. They recommend to use in this method a prepurified form of staphylococcal beta-toxin and of streptococcal CAMP-factor instead of the exclusively beta-tonin-producing strain of Staphylococcus aureus and instead of the intensively CAMP-test positive Streptococcus agalactiae strain, respectively. The authors determined concurrently staphylococcal hemolysins, using a three-plate method in which alpha-antitoxin was employed, to ensure a better evidence of alpha-toxin. A total of 494 staphylococcal strains were examined by both methods. Of this number, 446 Staphylococcus aureus strains were of diverse host origin and 48 were coagulase-negative staphylococcal strains. On the basis of the various hemolytically active staphylococcal toxins, the authors recommend the suggested modification of the one-plate method for their routine detection.

Animals↗

A simple method of detecting staphylococcal hemolysins.

A modification of the "one-plate method" for detection of staphylococcal hemolysins has been described. Bacterial strains of Staphylococcus aureus, Streptococcus agalactiae and Cornebacterium pseudotuberculosis were replaced by their prepurified hemolytically active exosubstances: beta-toxin, CAMP-factor, and, the exosubstance of Corynebacterium pseudotuberculosis called COREX. By means of the modification described, exact detection of hemolysins in possible with staphylococcal strains producing one type of hemolysin as well as with strains producing a combination of hemolysins.

Bacterial Toxins↗