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921.
Background
Analysis of gingival crevicular fluid (GCF) samples may give information of unattached (planktonic) subgingival bacteria. Our study represents the first one targeting the identity of bacteria in GCF.Methodology/Principal Findings
We determined bacterial species diversity in GCF samples of a group of periodontitis patients and delineated contributing bacterial and host-associated factors. Subgingival paper point (PP) samples from the same sites were taken for comparison. After DNA extraction, 16S rRNA genes were PCR amplified and DNA-DNA hybridization was performed using a microarray for over 300 bacterial species or groups. Altogether 133 species from 41 genera and 8 phyla were detected with 9 to 62 and 18 to 64 species in GCF and PP samples, respectively, per patient. Projection to latent structures by means of partial least squares (PLS) was applied to the multivariate data analysis. PLS regression analysis showed that species of genera including Campylobacter, Selenomonas, Porphyromonas, Catonella, Tannerella, Dialister, Peptostreptococcus, Streptococcus and Eubacterium had significant positive correlations and the number of teeth with low-grade attachment loss a significant negative correlation to species diversity in GCF samples. OPLS/O2PLS discriminant analysis revealed significant positive correlations to GCF sample group membership for species of genera Campylobacter, Leptotrichia, Prevotella, Dialister, Tannerella, Haemophilus, Fusobacterium, Eubacterium, and Actinomyces.Conclusions/Significance
Among a variety of detected species those traditionally classified as Gram-negative anaerobes growing in mature subgingival biofilms were the main predictors for species diversity in GCF samples as well as responsible for distinguishing GCF samples from PP samples. GCF bacteria may provide new prospects for studying dynamic properties of subgingival biofilms. 相似文献922.
The prespore-specific activation of sigma factor SigF (σF) in Bacillus subtilis has been explained mainly by two factors, i.e., the transient genetic asymmetry and the volume difference between the mother cell and the prespore. Here, we systematically surveyed the effect of these two factors on sporulation using a quantitative modeling and simulation architecture named hybrid functional Petri net with extension (HFPNe). Considering the fact that the transient genetic asymmetry and the volume difference in sporulation of B. subtilis finally bring about the concentration difference in two proteins SpoIIAB (AB) and SpoIIAA (AA) between the mother cell and the prespore, we have surveyed the effect of AB and AA concentration on the prespore-specific activation of σF occurring in the early stage of sporulation. Our results show that the prespore-specific activation of σF could be governed by the ratio of AA to AB rather than their concentrations themselves. Our model also suggests that B. subtilis could maximize the ratio of AA to AB in the prespore and minimize it in the mother cell by employing both the transient genetic asymmetry and the volume difference simultaneously. This might give a good explanation to the co-occurrence of the transient asymmetry and the volume difference during sporulation of B. subtilis. In addition, we suggest for the first time that the σF activation in the prespore might be switched off by the decrease in the ratio of AA to AB after the transient genetic asymmetry is to an end by completion of DNA translocation into the prespore. 相似文献
923.
Joon-Chul Kim Min-Jeong Son Krishna P. Subedi Do Han Kim Sun-Hee Woo 《Molecules and cells》2010,29(4):387-395
HL-1 cells are the adult cardiac cell lines available that continuously divide while maintaining an atrial phenotype. Here
we examined the expression and localization of inositol 1,4,5-trisphosphate receptor (IP3R) subtypes, and investigated how pattern of IP3-induced subcellular local Ca2+ signaling is encoded by multiple IP3R subtypes in HL-1 cells. The type 1 IP3R (IP3R1) was expressed in the perinucleus with a diffuse pattern and the type 2 IP3R (IP3R2) was expressed in the cytosol with a punctate distribution. Extracellular ATP (1 mM) elicited transient intracellular Ca2+ releases accompanied by a Ca2+ oscillation, which was eliminated by the blocker of IP3Rs, 2-APB, and attenuated by ryanodine. Direct introduction of IP3 into the permeabilized cells induced Ca2+ transients with Ca2+ oscillations at ⩾ 20 μM of IP3, which was removed by the inhibition of IP3Rs using 2-APB and heparin. IP3-induced local Ca2+ transients contained two distinct time courses: a rapid oscillation and a monophasic Ca2+ transient. The magnitude of Ca2+ oscillation was significantly larger in the cytosol than in the nucleus, while the monophasic Ca2+ transient was more pronounced in the nucleus. These results provide evidence for the molecular and functional expression
of IP3R1 and IP3R2 in HL-1 cells, and suggest that such distinct local Ca2+ signaling may be correlated with the punctate distribution of IP3R2s in the cytosol and the diffuse localization of IP3R1 in the peri-nucleus. 相似文献
924.
925.
Rhee YJ Han CR Kim WC Jun DY Rhee IK Kim YH 《Journal of microbiology and biotechnology》2010,20(10):1378-1385
A novel agarolytic bacterium KY-YJ-3, producing extracellular agarase, was isolated from the freshwater sediment of the Sincheon River in Daegu, Korea. On the basis of gram-staining data, morphology, and phylogenetic analysis of the 16S rDNA sequence, the isolate was identified as Cellvibrio sp. By ammonium sulfate precipitation followed by Toyopearl QAE-550C, Toyopearl HW-55F, and Mono-Q column chromatography, the extracellular agarase in the culture fluid could be purified 120.2-fold with yield of 8.1%. The specific activity of the purified agarase was 84.2 U/mg. The molecular mass of the purified agarase was 70 kDa as determined by dodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal temperature and pH of the purified agarase were 35 degrees C and pH 7.0, respectively. The purified agarase failed to hydrolyze the other polysaccharide substrates, including carboxymethyl (CM)-cellulose, dextran, soluble starch, pectin, and polygalacturonic acid. Kinetic analysis of the agarose-hydrolysis catalyzed by the purified agarase using thin layer chromatography (TLC) exhibited that the main products were neoagarobiose, neoagarotetraose, and neoagarohexaose. These results demonstrated that the newly isolated freshwater agarolytic bacterium KY-YJ-3 was a Cellvibrio sp., and could produce an extracellular beta-agarase, which hydrolyzed agarose to yield neoagarobiose, neoagarotetraose, and neoagarohexaose as the main products. 相似文献
926.
927.
Richland Tester Xuefei Tan Gregory R. Luedtke Imad Nashashibi Kurt Schinzel Weiling Liang Joon Jung Sundeep Dugar Albert Liclican Jocelyn Tabora Daniel E. Levy Steven Do 《Bioorganic & medicinal chemistry letters》2010,20(8):2560-2563
Optimization of a tri-substituted N-pyridyl amide led to the discovery of a new class of potent N-pyrimidyl amide based p38α MAP kinase inhibitors. Initial SAR studies led to the identification of 5-dihydrofuran as an optimal hydrophobic group. Additional side chain modifications resulted in the introduction of hydrogen bond interactions. Through extensive SAR studies, analogs bearing free amino groups and alternatives to the parent (S)-α-methyl benzyl moiety were identified. These compounds exhibited improved cellular activities and maintained balance between p38α and CYP3A4 inhibition. 相似文献
928.
929.
NamHui Yim Do Thi Ha Trinh Nam Trung Jin Pyo Kim SangMyung Lee MinKyeun Na HyunJu Jung Hyun Su Kim Young Ho Kim KiHwan Bae 《Bioorganic & medicinal chemistry letters》2010,20(3):1165-1168
Nine compounds isolated from the leaf and stem of Vitis amurensis Rupr. (Vitaceae) were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Streptococcus sanguis, which are associated with caries and periodontal disease, respectively. The results of several antimicrobial tests, including MIC, MBC, and TBAI, showed that three compounds inhibited the growth of the test bacteria at concentrations ranging from 12.5 to 50 μg/mL. Among these compounds, compound 5, trans-ε-viniferin, displayed the strongest activity against S. mutans and S. sanguis with MIC values of 25 and 12.5 μg/mL, respectively. This is the first report on the antimicrobial activity of stilbenes and oligostilbenes isolated from the leaf and stem of V. amurensis. Thus, this result suggests that natural antimicrobial compounds derived from V. amurensis may benefit oral health as plaque-control agents for the prevention of dental caries and periodontal disease. 相似文献
930.
Rhinacanthus spiciformis Y. F. Deng, Z. L. Lin & D. V. Hai, a new species from northern Vietnam previously misidentified as R. calcaratus is described and illustrated. This new species differs from all other Asian species of Rhinacanthus in the inflorescence being unbranched or comprised of trifurcate-branched spikes, and the lower lip of corolla with conspicuous purple stripes near throat and on lobes. The pollen morphology and chromosome number are presented. It is proposed to be accessed as Least Concern (LC) according to the IUCN categories and criteria. 相似文献