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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↗
PubMed1983

[Diagnosis of neonatal streptococcus group B infection in the obstetric department?].

Infections with streptococcus group B of the newborn are at present one of the most dreaded diseases seen by obstetricians and pediatricians. No successful management plans have been developed by special diagnosis and treatment. The main problem is the lack of early recognition of the infected and not only colonized newborn in the obstetric unit. The use of a latex agglutination test from the urine of the newborn in the obstetric unit has improved the results of the diagnosis and treatment of streptococcus group B infections.

Hospitals, Maternity↗
PubMed2004

[Screening for hemolytic streptococcus group B in pregnancy and prevention of infection in neonates].

OBJECTIVE: The aim of this study was to evaluate the influence of Group B streptococcus (GBS) screening and intrapartum antibiotic prophylaxis to the incidence of GBS disease in newborns. DESIGN: Prospective non-randomised study. SETTING: IInd Clinic of Obstetric and Gynaecology LFUK and FNsP Ruzinov, Bratislava, Slovakia. METHODS: We enrolled 3023 newborns (754 in the study group, 2269 in the control group), which were born between 1.9.2000 and 31.3.2003. In both groups we compared following variables: total number of infectious diseases in newborns, number and forms of GBS neonatal disease, number of perinatal death due to GBS disease. RESULTS: There was no GBS disease in the study group of 754 newborns. Mothers of these newborns had one screening culture in 35-36th week of gestation. One swab was taken from vagina and anus. GBS carriers (161-21.4%) were administered i.v. intrapartum antibiotic prophylaxis with Penicillin G i.v., or, when allergy to penicillin was in history, with Clindamycin i.v. In the control group of 2269 newborns, whose mothers had no prevention, the incidence of GBS neonatal disease reached 7.5/1000 newborns (17 cases). The incidence of invasive GBS neonatal disease was 2.6/1000 newborns. CONCLUSION: The authors have noticed a significant decrease in incidence of GBS neonatal disease after implication of GBS screening and intrapartum antibiotic prophylaxis.

Anal Canal↗
PubMed1990

[The effect of immunization with Streptococcus group A on the development of delayed hypersensitivity to BCG antigens in mice of different strains].

Antibodies to group A streptococcal polysaccharide (A-PS) have been shown to appear within three weeks after the injection of group A streptococcus culture, heat-killed and treated with pepsin (A-STP), in the blood of not only BALB/c mice, but also CBA mice. As revealed in this study, in BALB/c mice antibodies are mainly active against the group-specific antigenic determinant (AD) of A-PS and in CBA mice, against the rhamnose AD of A-PS, common for streptococci of different groups. This study has revealed that the appearance of antibodies to the rhamnose AD of A-PS in the blood of CBA mice inhibits antigen-specific cytotoxicity, appearing with the development of delayed hypersensitivity to BCG antigens. This effect is not linked with the immunization of the animals with high doses of streptococci. Experiments have shown that the in vitro transfer of the inhibition of antigen-specific cytotoxicity to lymph node cells of normal BCG-sensitized animals may be carried out with lymph node cells of CBA mice, immunized with A-STP and having antibodies to the rhamnose AD of A-PS, but not with the serum containing these antibodies. The mechanisms of this effect are discussed.

Animals↗
PubMedDate not supplied

[Factors associated with Streptococcus group B colonization in pregnant women in Los Altos, Chiapas].

OBJECTIVE: To estimate the prevalence and analyze the factors associated with group B Streptococcus (GBS) colonization in pregnant women of Los Altos, Chiapas, Mexico. MATERIAL AND METHODS: Between February and September 1999, a cross-sectional study was conducted among 910 women who sought delivery care at three public hospitals of San Cristobal de Las Casas, Chiapas. Vaginal and perianal samples were taken for GBS detection by bacteriological culture. Identification of groups and serotypes was performed using latex agglutination. The analysis of factors associated with colonization was done using chi-squared tests and log-linear modeling. RESULTS: GBS colonization was found in 8.6% (95% CI 6.8-10.5) of study subjects. Women with the greatest likelihood of colonization were those with > or = 5 pregnancies, residents of counties with high levels of poverty, working outside the home, and living in homes in which the head of household worked in agriculture (26.8%, OR = 7.25, 95% CI 1.83-28.67). CONCLUSIONS: In the study area, it is necessary that actions aiming to prevent and control infections by GBS be directed principally at those groups of women with the highest probability of colonization, in order to diminish the perinatal transmission of GBS.

Adolescent↗
PubMed1989

[Comparison of three pigment production media with CAMP and hippurate hydrolysis tests for the identification of beta-streptococcus group B].

Three pigment production media were compared with CAMP and hippurate hydrolysis tests for the identification of beta-Streptococcus group B. A total of 129 clinical isolates of beta-Streptococcus group B and 287 beta-Streptococcus non group B were tested. The results show that sensitivities are: pigment medium, 99.2%, DMS medium, 95.6%, Columbia agar, 92.8%, CAMP test, 96.3%, hippurate hydrolysis test, 97.6%. As for specificities results show: CAMP test, 99.7%, the other tests, 100%; respectively. Pigment medium is a simple, convenient methodology.

Bacteriological Techniques↗
PubMed1981

Purification of Streptococcus group C bacteriophage lysin.

A simple procedure for the purification of Streptococcus group C phage lysin to apparent homogeneity is described. The electrophoretically pure, enzymatically stable polypeptide of 98,000 molecular weight converted Streptococcus (groups A, F, and H) cells into spheroplasts within 5 min at 0 degrees C or within less than a minute at 37 degrees C.

Bacteriolysis↗
PubMed2004

Streptococcus group B (GBS)--characteristic, occurrence in children and adolescents with type 1 diabetes mellitus.

Group B streptococcus causes infections in woman during pregnancy and confinement, perinatal infections in newborns related to mothers carrier-state and in adults, mostly in the elderly, with one or more predisposing to infections conditions. Diabetes mellitus is the most common underlying condition. The aim of the study was to determine the frequency of GBS occurrence and GBS antibiotic susceptibility in children and adolescents with type 1 diabetes mellitus. In years 2000--2002 occurrence of GBS in some clinical materials (urine, swabs from pharynx and urogenital tract) taken from 161 diabetics: 90 girls and 71 boys, hospitalized for newly diagnosed diabetes or insufficient metabolic control/longer duration of diabetes and 37 children with hypostatura (control group) aged from 5-17 years, was examined. Susceptibility of isolated GBS strains to ampicillin, erythromycin and clindamycin was determined. GBS were obtained from different materials from 36 (22.4%) diabetic children--25 girls (27.8%), and 11 boys (15.5%). In all examined groups GBS was detected significantly in children with insufficient metabolic control/longer duration of diabetes (27 of 36 children; p =0.029, chi2=4.773). GBS in girls was isolated mainly from vestibule of vagina (25 cases) and in few cases (4) from the pharynx. GBS in boys was grown from materials from urethra (6 cases) and pharynx (5 cases). In the control group, GBS colonization was observed only in one case. All isolates (40 strains) were susceptible to penicillins, however lower susceptibility to erythromycin (3 resistant and 1 moderately sensitive) and clindamycin (3 resistant) were observed. High percentage of carriers of GBS both in girls and boys with diabetes mellitus is the potential risk factor of infection caused by GBS.

Adolescent↗
PubMed2001

[Streptococcus group A infections of skin, soft tissue and blood].

BACKGROUND: Group A streptococcus is one of the most common bacterial pathogens causing infections in tissue and organs, most frequently throat and skin. Since the late 1980s there have been reports from Scandinavia and many other countries documenting a resurgence of highly invasive infections such as puerperal fever, necrotizing fasciitis, myositis and sepsis. MATERIAL AND METHODS: On the basis of relevant studies and reviews and a clinical study of 61 patients between 1992 and 1999 with necrotizing fasciitis and myositis at Haukeland University Hospital, Bergen, Norway, we present an overview of the prevalence, pathogenesis, clinical features and treatment of group A streptococcal infections in skin, soft tissue and blood. RESULTS AND INTERPRETATION: The reason for the increase in severe group A streptococcal infections is unclear. The clinical features depend on the level of infection (superficial skin, subcutis, fascia and muscle): the deeper the initial infection, the more frequent development of bacteraemia and life-threatening disease. Serious infections are associated with shock and multiorgan failure, i.e. streptococcal toxic shock syndrome. Early surgical debridement is essential in necrotizing fasciitis and myositis. Penicillin is still the drug of choice for milder infections. The addition of clindamycin is recommended in cases of more invasive infection.

Adult↗
PubMed1992

[Neonatal digestive implantation of streptococcus group B. Influence of antibiotic therapy].

Group B streptococcus (GBS) is an important cause of neonatal infection. Early-onset diseases are due to perinatal contamination. The epidemiology of late-onset infections is poorly known. Maternal colonization may be responsible for some of them. The relationships between neonatal colonization and late disease could be a colonization of the gut. The purpose of this 3 year-prospective study was to analyse the kinetics of gut colonization in neonates and the influence of antibiotherapy. One hundred and nineteen infants less than one month of age were included because of the presence of GBS in their gastric aspirates or GBS infection. Depending on the therapeutic strategy, the infants were separated into 3 groups: 1) amoxicillin plus aminoside greater than or equal to 10 days because of neonatal infection (28 infants), 2) same combination less than or equal to 5 days because a GBS infection was suspected but not confirmed (17 infants), 3) no antibiotics (77 infants). Fecal flora was regularly analysed by differential count. Antibiotics caused rapid disappearance of GBS from the gut. However, the same strain reappeared after stopping the antibiotics at a rate of 13.5%. Without antibiotics, GBS was implanted in 33% of cases. This difference of implantation rate is statistically significant (p less than 0.05). No GBS infection was observed in any infant after a follow-up examination of 6 months to 2 years. Among the clinical and bacteriological factors studied, adhesion only was correlated with the GBS implantation. These results allow to discuss therapeutic abstention in colonized infants without any signs of infection.

Ampicillin↗
PubMed2000

Bivalency and epitope specificity of a high-affinity IgG3 monoclonal antibody to the Streptococcus group A carbohydrate antigen. Molecular modeling of a Fv fragment.

The binding of Strep 9, a mouse monoclonal antibody (mAb) of the IgG3 subclass directed against the cell-wall polysaccharide of Group A Streptococcus (GAS), has been characterized. The intact antibody and proteolytic fragments of Strep 9 bind differently to GAS: the intact mAb and F(ab)2' have greater affinity for the carbohydrate epitope than the monomeric Fab or F(ab)'. A mode of binding in which Strep 9 binds bivalently to portions of the polysaccharide on adjacent chains on GAS is proposed. A competitive ELISA protocol using a panel of carbohydrate inhibitors shows that the branched trisaccharide, beta-D-GlcpNAc-(1-->3)-[alpha-L-Rhap-(1-->2)]-alpha-L-Rhap, and an extended surface are key components of the epitope recognized by Strep 9. Microcalorimetry measurements with the mAb and two synthetic haptens, a tetrasaccharide and a hexasaccharide, show enthalpy-entropy compensation as seen in other oligosaccharide-protein interactions. Molecular modeling of the antibody variable region by homology modeling techniques indicates a groove-shaped combining site that can readily accommodate extended surfaces. Visual docking of an oligosaccharide corresponding to the cell-wall polysaccharide into the site provides a putative model for the complex, in which a heptasaccharide unit occupies the site and the GlcpNAc residues of two adjacent branched trisaccharide units occupy binding pockets within the groove-shaped binding site.

Amino Acid Sequence↗
PubMedDate not supplied

[The properties of cell wall hydrolysates of Streptococcus group A].

Products obtained from lysis in the cell wall of group A streptococcus have been studied in different growth phases: at the end of the exponential phase and in the stationary one. Endo-beta-N-acetylmuramidase extracted from the culture liquid of Streptomyces levoris 96 has been used for lysis of streptococcus. It is stated that streptococcus cell walls isolated at different growth stages differ in the protein and polysaccharide content. High content of protein in the cell wall of a young culture makes lower the initial rate of the walls' hydrolysis by endo-beta-N-acetylmuramidase. However, with the enzyme penetration into peptidoglycan the rate of hydrolysis of cell walls gets higher and after four-hour incubation the lysis degree of walls of the 16- and 8-hour cultures reaches the equal value (63%). Studies in the protein composition of lysates of the streptococcus cell walls have shown that they contain at least 12 proteins most of which are acid and neutral ones.

Cell Wall↗
PubMed1988

[Identification of Streptococcus group A in children with pharyngitis, in ambulatory care, through pharyngeal culture].

574 cases of pharyngitis (patients 0.3-14 years aged) were studied. Throat swabs were obtained from all the children, inoculated into blood-agar plates and incubated aerobically at 37 degrees C, in the office, using the bacitracin test for identification of group A streptococci. The 25% of the cultures were positives (80% in the first 24 hours, and the rest in 48 hours). We did not find reliable clinical findings that enable us to diagnose streptococcal pharyngitis accurately. So that we conclude that demonstration of group A streptococcus in patients throat is essential and we find that throat culture is a practical and advisable method for the office practice.

Adolescent↗
PubMed1987

[Isolation and characteristics of surface proteins from Streptococcus group A].

Cell wall surface proteins of group A Streptococcus type 29 were extracted with 1 M hydroxylamine pH 6.0. The purification procedure included fractionation with ammonium sulfate and gel filtration on Sephadex G-150. SDS polyacrylamide gel electrophoresis revealed a number of proteins (approximately 20) with molecular mass of 70 kD; the difference in Mr between the proteins was 5-10 kD. Isoelectrofocusing demonstrated that the proteins are either acid (pI = 3.7) or weakly alkaline (pI = 7.7). Possible reasons for the heterogeneity of Streptococcus cell wall surface proteins are discussed.

Amino Acids↗
PubMed1986

[Antibiotic resistance of revertant cultures of Streptococcus group A and of unclassified streptococci isolated from the blood of rheumatism patients].

Sensitivity of one strain of group A Streptococcus, its L-form and revertant was tested to 7 antibiotics and it was observed that the revertant was highly resistant to beta-lactam antibiotics and lincomycin, tolerant to ristomycin and had a high value of MBcC/MIC for erythromycin and tetracycline. Testing of other analogous revertant strains showed the same results. In streptococcal strains freshly isolated from blood of patients with rheumatism and resistant to some antibiotics there were recorded by electron microscopy heterogeneity of their population and presence in it of a significant number of cells with altered (unevenly thickened) cell walls and cells with microcapsules on the cell wall surface characteristic of the revertants. In vivo occurrence of streptococcal revertants may be the cause of their antibiotic resistance which obviously requires correction of the rational antibiotic therapy schemes.

Anti-Bacterial Agents↗
PubMed1983

[Streptococcus group B septicemia. Analysis of 18 cases in adults and 10 in newborn infants].

From 1976 to 1981, 28 episodes of group B streptococcus (GBS) septicemia were identified in our hospital (CHUV, University Hospital Lausanne), 18 in 17 adults and 10 in newborns. The latter had acute respiratory distress syndrome (8 cases) or meningitis (2 cases). In adults the skin was the main source of infection (6 diabetic foot, 4 acute cellulitis complicating chronic skin diseases, 2 infections secondary to diagnostic procedures (capillary and ascitic taps) and 1 meningitis secondary to neurosurgery). The other sources of infection were 1 pharyngitis, 1 pneumonia and 1 pyelonephritis. Eleven patients had an underlying disease (7 diabetes and 4 malignancies). Four patients developed septic osteoarticular metastases, one after a 3 weeks' course of antibiotic. In the latter case, as well as in the two adult patients who died, the strains of GBS were found to be tolerant to penicillin. Thus, GBS septicemia are not rare in adults and occur often in compromised hosts such as diabetics. The portal of entry is frequently the skin and the course may be severe with distant complications.

Adult↗
PubMed1981

[Cross-reacting antigen common to stratified squamous epithelium and Streptococcus group A in tumors of epidermal origin].

A tissue-specific basal-cell antigen of stratified squamous epithelium which enters into cross reaction with group A streptococcus polysaccharide was detected in the cytoplasm of human basal- and squamous-cell tumor cells which are associated histogenetically with skin epithelium. However, it was not found in the cells of entodermal tumors (stomach and intestinal adenocarcinoma). Considering earlier reports on the detection of cross reacting antigen in experimental ectodermal tumors, these results suggest the development of an additional histogenetical method of differential diagnosis of human tumors which arise in ectodermal tegumental epithelium.

Adenocarcinoma↗