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ATCC Strain (atcc + strain)
Selected AbstractsRapid detection of bordetella pertussis by real-time PCR using SYBR green I and a LightCycler instrumentJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 5 2004S. K. Poddar Abstract A polymerase chain reaction (PCR) assay in real-time for detection of B. pertussis using SYBR green I as the reporter fluorophore and LightCycler instrument (a thermocycler coupled to a fluorescence detection device) was established and evaluated. The amplified amplicon using series diluted control prototype strain (ATCC strain #9797) of B. pertussis was analyzed for the fluorescent melting profile, and melting temperature (Tm) was determined. When examined, amplicons using a representative set of clinical isolates of B. pertussis were found to have the same Tm value (86 ± 0.5°C, the specificity parameter of detection) as the control prototype strain as expected. Amplified product was also analyzed and detected by agarose gel electrophoresis. The detection limit by fluorescent profile and Tm analysis was 10-fold better than that detected by agarose gel analysis. J. Clin. Lab. Anal. 18:265,270, 2004. © 2004 Wiley-Liss, Inc. [source] Effect of an essential oil-containing antiseptic mouthrinse on induction of platelet aggregation by oral bacteria in vitroJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2000E. J. Whitaker Abstract Background: With an increasing body of data suggesting an association between periodontitis and cardiovascular disease, studies have been conducted to elucidate potential mechanisms by which oral bacteria might exert systemic effects. 2 oral bacteria, Streptococcus sanguis and Porphyromonas gingivalis, have been shown to induce platelet aggregation in vitro. This study was conducted to determine the effect of treatment with an essential oil mouthrinse (Listerine® Antiseptic) on the platelet-aggregating activity of these organisms. Method: Bacteria were grown under standard culture conditions. S. sanguis ATCC strain 10556 was exposed for 3 min to the essential oil mouthrinse at either full strength or a 1:1 dilution, while P. gingivalis FDC strain 381 was exposed to the essential oil mouthrinse at a 1:10 dilution. Positive control cells were treated with Hanks balanced salt solution (HBSS). Aggregation was measured using a recording platelet aggregometer. The assay of each organism in its respective mouthrinse dilution(s) or HBSS was repeated 5 times. Results: In all cases, the HBSS-treated organisms induced platelet aggregation, with mean(±S.E.) lag times of 12.30 (±1.36) min and 11.36 (±0.58) min for P. gingivalis and S. sanguis, respectively. In contrast, treatment with the essential oil mouthrinse completely inhibited the platelet aggregating activity of P. gingivalis and of S. sanguis exposed to the 1:1 mouthrinse dilution in all assays; the aggregating activity of S. sanguis treated with full-strength mouthrinse was completely inhibited in 4 of 5 assays, and inhibited by 75% in the 5th, for a mean inhibition of 95±1.5%. Conclusion: This study provides additional evidence that the essential oil mouthrinse can interfere with bacterial cell surface-associated activities which may have clinical relevance. [source] Divergence in gene expression related to variation in host specificity of an ectomycorrhizal fungusMOLECULAR ECOLOGY, Issue 12 2004ANTOINE LE QUÉRÉ Abstract Ectomycorrhizae are formed by mutualistic interactions between fungi and the roots of woody plants. During symbiosis the two organisms exchange carbon and nutrients in a specific tissue that is formed at the contact between a compatible fungus and plant. There is considerable variation in the degree of host specificity among species and strains of ectomycorrhizal fungi. In this study, we have for the first time shown that this variation is associated with quantitative differences in gene expression, and with divergence in nucleotide sequences of symbiosis-regulated genes. Gene expression and sequence evolution were compared in different strains of the ectomycorrhizal fungus Paxillus involutus; the strains included Nau, which is not compatible with birch and poplar, and the two compatible strains Maj and ATCC200175. On a genomic level, Nau and Maj were very similar. The sequence identity was 98.9% in the 16 loci analysed, and only three out of 1075 genes analysed by microarray-based hybridizations had signals indicating differences in gene copy numbers. In contrast, 66 out of the 1075 genes were differentially expressed in Maj compared to Nau after contact with birch roots. Thirty-seven of these symbiosis-regulated genes were also differentially expressed in the ATCC strain. Comparative analysis of DNA sequences of the symbiosis-regulated genes in different strains showed that two of them have evolved at an enhanced rate in Nau. The sequence divergence can be explained by a decreased selection pressure, which in turn is determined by lower functional constraints on these proteins in Nau as compared to the compatible strains. [source] Hyptis pectinata essential oil: chemical composition and anti- Streptococcus mutans activityORAL DISEASES, Issue 6 2008PFC Nascimento Objectives:, The aim of the present study was to evaluate the anti- Streptococcus mutans activity of Hyptis pectinata essential oil, and present its promising potential against oral diseases. Materials and methods:, The essential oil of H. pectinata was obtained by hydrodistillation from dried leaves and analyzed by GC / MS. The effectiveness of this essential oil regarding the antimicrobial activity against several S. mutans strains was investigated by the agar diffusion and microdilution methods, and chlorohexidine was used as a standard control. Results:, The H. pectinata essential oil exhibited considerable inhibitory effect against either all the clinical isolates obtained from patients' saliva or the ATCC strains tested, with minimum inhibitory and bactericidal concentrations of 200 ,g ml,1. The study also compared the efficiency of the emulsifying agents Tween 20, Tween 80, dimethyl sulfoxide and propylene glycol in H. pectinata essential oil when tested against S. mutans. The data obtained confirmed the better inhibitory effect of the oil when using all tested diluents, although Tween 80 seemed to be more suitable for emulsification. Conclusion:, According to our results, H. pectinata essential oil can be considered a promising alternative to chlorhexidine for the control of oral bacteria-related diseases and hygiene. [source] | ||||||||||