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Results for “group A Streptococcus”

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At least 19 recordsLinked to original sources

PubMed1977

Streptococcus group B typing: comparison of counter-immunoelectrophoresis with the precipitin method.

The method of counter-immunoelectrophoresis (CIE) was tested for its applicability to group B streptococcus typing. The results obtained were compared with the typing by the ring precipitin test. Identical antigens and identical hyperimmune typing serum batches had been used in both methods. A large majority of 75 freshly isolated strains were typed identically by both methods. Five strains with a weak antigenic outfit were untypable by the ring precipitin test but were typed by CIE owing to a higher sensitivity of CIE method. Two strains were typable by the precipitin test but not by CIE; an explanation for this phenomenon is lacking. The CIE method in group B typing is specific, rapid, highly sensitive and relatively simple. It requires strict maintenance of standard conditions. The method is economical with respect to manipulation and material, requires small amounts of diagnostic antisera. Potent antisera may be used diluted. Moreover, sera for CIE typing need not be absorbed to remove group B antibodies. CIE method is practicable for group B streptococcus typing, especially in laboratories carrying out routine large scale type identification.

Animals↗

PubMedDate not supplied

[Lysis of the cell walls of streptococcus group A by Streptomyces griseus pronase].

The effect of Streptomyces griseus pronase on Streptococcus group A cell walls was studied. Cell walls were shown to be lysed by pronase, the lysis level being dependent on the molarity of the potassium-phosphate buffer used. With an increase in the buffer molarity from 0.005 M to 0.05 M lysis of cell walls decreased from 70-80% to 30%. By DEAE-cellulose chromatography lysates were separated into two fractions the first of which contained a group specific polysaccharide. A preparative method of obtaining a group specific polysaccharide of Streptococcus group A using Streptomyces griseus pronase under mild conditions is described.

Antigens, Bacterial↗

PubMed1977

Streptococcus group B: an old bug with new dangers.

Infection of the newborn infant with Group B hemolytic streptococcus is increasing in importance as other pathogens decline. Such infection may appear within the first 48 hours of life and resemble respiratory distress syndrome, or around the tenth day, when signs of meningeal irritation may be present. Early onset disease may be due to any of the five serotypes of the Group B streptococcus and is fatal in a high percentage of cases. Late onset infection usually is due to serotype III. The epidemiologic aspects of early and late infection appear to differ, and a nosocomial source may be involved in the latter. Penicillin prophylaxis may be useful.

Humans↗

PubMed1978

[Autolysis of hemolytic streptococcus group A].

As revealed, autolytic enzymatic system of hemolytic streptococcus, group A, expressed the maximal activity at the end of the exponential growth phase. Autolysis was accompanied by the release of N-acetylaminosugars and of free amino group. Optimal conditions for the lytic system function were chosen (composition, ionic strength, and buffer pH). The activating action of trypsin and chemotrypsin was demonstrated.

Bacteriolysis↗

PubMed1978

[Selection of phage-resistent clones of streptococcus group A and their properties].

In studying the effects induced by virulent phage CAI in the sensitive cultures of streptococcus, group A, a possibility was shown of selection of phage-resistant clones with the altered enzymatic activity. These clones lost their capacity to produce proteinase and retained residual lipoproteinase activity. This evidence correlates with literature data indicating that phage-resistant streptococci served as good producers of M-protein--the main virulence factor. Infection of the culture producing streptokinase with phage CAI with a definite infection multiplicity led to an increase of the enzyme activity in the culture fluid. This process was accompanied by selection of the resistant strains characterized by greater streptokinase production and greater enzyme stability. As suggested, the latter could result from the absence of proteolytic activity in the phage-resistant clone.

Bacteriophages↗

PubMed1979

The effects of combined action of beta-lactame and aminoglycoside antibiotics on resistant strains of streptococcus group D.

The aim of the paper was to study the effect of benzylpenicillin, cloxacillin and ampicillin in combination with streptomycin, kanamycin and gentamicin on antibiotic-resistant strains of Streptococcus group D. Most frequently the synergistic effect was observed when cloxacillin was combined with streptomycin (76%), cloxacillin with kanamycin (63%) and benzylpenicillin with streptomycin (53%). In some cases the synergistic effect was so pronounced that MIC of two antibiotics used in combination was equal or lower than levels of these antibiotics in patients sera. It is assumed that these combinations may have therapeutic meaning.

Ampicillin↗

PubMed1977

[Reactions of antibodies to streptococcus group A antigens with fibroblasts of human heart interstitial connective tissue].

The indirect immunofluorescence method was applied to the study of the serum of rabbits immunized with fractions containing nontype-specific antigens of streptococcus, group A, belonging to the cell wall proteins. Antibodies reacting with fibroblasts of the interstitial connective tissue of the human heart were revealed in the sera. On the basis of the experimental results of absorption a supposition was put forward on the presence of a cross-reacting antigen common with the fibroblast antigen in some hydrochloric extracts obtained from streptococci, groups A and C.

Animals↗

PubMed1979

Rapid diagnosis of beta-haemolytic streptococcus group B endocarditis by buffy-coat examination and gas-liquid chromatography.

A semicomatose 34-year-old man had fever, heart murmur, and multiple gangrenous lesions. Several blood cultures were negative. Cultures of the heart valve grew beta-haemolytic streptococcus group B. The organism was seen in buffy-coat examination of the venous blood. The gas-liquid chromatogram of the serum was different from those of normal controls and of patients with invasive candida infection; it closely mimicked the one obtained from the organism itself. These studies promise to be valuable diagnostic adjuncts.

Adult↗

PubMed1977

[Pregnant vaginal carriers of beta-haemolytic streptococcus group B (author's transl)].

Vaginal schwabs of 142 pregnant women in different stages of pregnancy have been studied. 45 women who weren't pregnant and had no signs of vaginal infections, were the control group of the study. A higher incidence of "Streptococcus agalactiae" in vaginal schwabs of women who weren't pregnant (15.5%), as compared to the pregnant women (7.1%) was observed. A lower incidence of "Streptococcus agalactiae" was found in the last three months of pregnancy (1.8%) which is in direct relation to the low number of neonatal sepsis caused by "Steptococcus agalactiae" found in our country.

Female↗

PubMed1977