Viridans Streptococci
Mostrando 13-24 de 236 artigos, teses e dissertações.
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13. Sialidase activity of the "Streptococcus milleri group" and other viridans group streptococci.
Viridans group streptococci were examined for the production of sialidase (neuraminidase) activity, using the fluorescent substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid in a simple and rapid (15-min) assay. Sialidase was produced by all strains of Streptococcus oralis and S. intermedius and by a majority of S. mitis strains. S. mutans, S. sob
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14. Identification of clinically relevant viridans group streptococci to the species level by PCR.
A PCR assay that allows identification of clinically relevant viridans group streptococci (Streptococcus gordonii, S. mitis, S. mutans, S. oralis, S. salivarius, and S. sanguis) to the species level and identification of milleri group streptococci (S. anginosus, S. constellatus, and S. intermedius) to the group level was developed. This assay was based on sp
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15. Quantitative assay of glycocalyx produced by viridans group streptococci that cause endocarditis.
A quantitative method to determine glycocalyx production by strains of viridans group streptococci from patients with endocarditis is presented. There is good correlation between this new tryptophan quantitative assay and qualitative assays employing polysaccharide stains (ruthenium red, periodic acid-Schiff, and Cellufluor) or the Molisch test. The quantifi
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16. Cytokine production by human epithelial and endothelial cells following exposure to oral viridans streptococci involves lectin interactions between bacteria and cell surface receptors.
In order to examine the possible implication of human epithelial and endothelial cells in the pathogenesis of various diseases associated with oral viridans streptococci, we tested the immunomodulatory effects of 11 representative strains of oral viridans streptococci on human epithelial KB cells and endothelial cells. We then examined the possible role of t
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17. Association of viridans group streptococci from pregnant women with bacterial vaginosis and upper genital tract infection.
The prevalence and role of viridans group streptococci in the female genital tract have not been well described. In this study of 482 pregnant women, 147 (30%) were culture positive for viridans group streptococci. Of 392 women with predominant Lactobacillus morphotypes by Gram stain (normal), 110 (28%) were colonized with viridans group streptococci, compar
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18. In vitro activity of LY146032 against staphylococci, streptococci, and enterococci.
The in vitro activities of LY146032 and seven comparative antimicrobial agents against 14 species of staphylococci, streptococci, and enterococci were studied. MICs of LY146032 were less than or equal to 0.5 microgram/ml for all staphylococci, including oxacillin-resistant strains; less than or equal to 0.25 microgram/ml for all streptococci (except viridans
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19. Physiological differentiation of viridans streptococci.
Twelve hundred and twenty-seven clinical isolates and eighty stock strains of viridans streptococci were tested for serological and physiological characteristics. Because the serological reactions of these strains varied, a differentiation scheme could not be based on these reactions. For the same reason, there could be no correlation of serological characte
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20. Evaluation of the rapid strep system for species identification of streptococci.
The Rapid Strep system (API System S.A., Montalieu-Vercieu, France) was evaluated, without additional tests, in the identification of 209 streptococci. Organisms included 59 beta-hemolytic, 36 group D, 24 Streptococcus pneumoniae, and 90 viridans group streptococci. The Rapid Strep system correctly identified to species level 69.5% of the beta-hemolytic stra
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21. Presumptive Identification of Group A, B, and D Streptococci
A battery of five tests was used for presumptive identification of the pathogenic streptococci. The non-serological methods included determination of hemolysis for all strains, bacitracin susceptibility for group A streptococci, hippurate hydrolysis by group B streptococci, and bile-esculin reaction for group D streptococci. Enterococcal group D streptococci
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22. Penicillin-induced effects on streptomycin uptake and early bactericidal activity differ in viridans group and enterococcal streptococci.
In vitro studies with penicillin and [3H]streptomycin in four strains of streptococci (S. faecalis, S. sanguis, and S. mitis) were performed by simultaneously measuring the rates of bacterial killing and uptake of streptomycin. In S. faecalis, penicillin stimulated streptomycin uptake, as has been shown by Moellering and Weinberg (R. C. Moellering, Jr., and
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23. A simple procedure for isolation of cloning vectors and endogenous plasmids from viridans group streptococci and Staphylococcus aureus.
Isolation of plasmid DNA from viridans group streptococci is difficult, and preparations are often heavily contaminated with chromosomal DNA. We developed a simple protocol to isolate pure plasmid DNA for use in different molecular techniques, including automated sequencing. The protocol is also applicable for plasmid isolation from Staphylococcus aureus. In
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24. Rapid identification of enterococci.
A 4-h method was devised to differentiate the non-beta-hemolytic streptococci into three categories: enterococci, group D nonenterococci, and viridans streptococci. All of the Streptococcus faecalis, 90% of the Streptococcus faecium (enterococci), and 96% of the Streptococcus bovis biotype I (group D nonenterococci) cultures were correctly identified by the