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961.
Liu B Xie JX Tsang LL Rowlands DK Ho LS Gou YL Chung YW Chan HC 《Cell biology international》2008,32(1):86-92
Bak Foong pill (BFP) is a well-known traditional Chinese medicine used for treatment of various gynaecological disorders. In addition, it exerts beneficial effects on other functional systems including the central nervous system. In the present study, we have investigated the possible neuroprotective action of BFP upon the nigrostriatal dopaminergic system by examining its effect on the expression patterns of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the 1-methyl-4-phenyl-1,2,3,6-tetrahyrdropyridine (MPTP)-induced Parkinson's disease (PD) mouse model. MPTP significantly decreased TH and DAT mRNA levels in the striatum and midbrain of both female and male C57BL/6 mice. However, with BFP pre-treatment mice showed a reduced neurotoxicity, with TH and DAT mRNA levels either not affected by MPTP or affected to a lesser extent in the midbrain and striatum when compared to vehicle treated animals. Possible anti-apoptotic activity of BFP was further studied in a dopamine-secreting neuroendocrine cell line, PC12. In this assay, MPTP elevated the expression of a pro-apoptotic gene, Bax, while this expression was reduced by BFP pre-treatment. Flow cytometry results also revealed that the effect of MPTP-induced apoptosis in PC12 cell lines was significantly reduced by BFP. The present results suggest that BFP is able to protect dopaminergic neurons from neurotoxin-induced neuronal injury with anti-apoptotic activity being one of the possible mechanisms. 相似文献
962.
963.
Yang ZH Zeng R Yang G Wang Y Li LZ Lv ZS Yao M Lai B 《Journal of industrial microbiology & biotechnology》2008,35(9):1047-1051
As an important organic compound, chiral alcohols are the key chiral building blocks to many single enantiomer pharmaceuticals. Asymmetric reduction of the corresponding prochiral ketones to produce the chiral alcohols by biocatalysis is one of the most promising routes. Asymmetric reduction of different kinds of non-natural prochiral ketones catalyzed by various plants tissue was studied in this work. Acetophenone, 4'-chloroacetophenone and ethyl 4-chloroacetoacetate were chosen as the model substrates for simple ketone, halogen-containing aromatic ketone and beta-ketoesters, respectively. Apple (Malus pumila), carrot (Daucus carota), cucumber (Cucumis sativus), onion (Allium cepa), potato (Soanum tuberosum), radish (Raphanus sativus) and sweet potato (Ipomoea batatas) were chosen as the biocatalysts. It was found that these kinds of prochiral ketoness could be reduced by these plants tissue with high enantioselectivity. Both R- and S-form configuration chiral alcohols could be obtained. The e.e. and chemical yield could reach about 98 and 80% respectively for acetophenone and 4'-chloroacetophenone reduction reaction with favorable plant tissue. And the e.e. and yield for ethyl 4-chloroacetoacetate reduction reaction was about 91 and 45% respectively. 相似文献
964.
Summary: Accurate estimation of DNA copy numbers from arraycomparative genomic hybridization (CGH) data is important forcharacterizing the cancer genome. An important part of thisprocess is the segmentation of the log-ratios between the sampleand control DNA along the chromosome into regions of differentcopy numbers. However, multiple algorithms are available inthe literature for this procedure and the results can vary substantiallyamong these. Thus, a visualization tool that can display thesegmented profiles from a number of methods can be helpful tothe biologist or the clinician to ascertain that a feature ofinterest did not arise as an artifact of the algorithm. Sucha tool also allows the methodologist to easily contrast hismethod against others. We developed a web-based tool that applies a number of popularalgorithms to a single array CGH profile entered by the user.It generates a heatmap panel of the segmented profiles for eachmethod as well as a consensus profile. The clickable heatmapcan be moved along the chromosome and zoomed in or out. It alsodisplays the time that each algorithm took and provides numericalvalues of the segmented profiles for download. The web interfacecalls algorithms written in the statistical language R. We encouragedevelopers of new algorithms to submit their routines to beincorporated into the website. Availability: http://compbio.med.harvard.edu/CGHweb Contact: peter_park{at}harvard.edu
Associate Editor: Keith Crandall 相似文献
965.
966.
A pyrene-degrading consortium from deep-sea sediment of the West Pacific and its key member Cycloclasticus sp. P1 总被引:2,自引:0,他引:2
A pyrene-degrading bacterial consortium was obtained from deep-sea sediments of the Pacific Ocean. The consortium degraded many kinds of polycyclic aromatic hydrocarbons (PAHs), including naphthalene, phenanthrene, pyrene, acenaphthene, fluorene, anthracene, fluoranthene, 2-methylnaphthalene and 2,6-dimethylnaphthalene, but it did not grow with chrysene and benzo[alpha]pyrene. With methods of plate cultivation and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), 72 bacteria belonging to 22 genera were detected from this consortium. Among the detected bacteria, the following genera frequently occurred: Flavobacterium, Cycloclasticus, Novosphingobium, Halomonas, Achromobacter, Roseovarius and Alcanivorax. The first two genera showed the strongest bands in denaturing gradient gel electrophoresis (DGGE) profiles and appeared in all PAH treatments. By now, only one isolate designated P1 was confirmed to be a pyrene degrader. It was identified to be Cycloclasticus spirillensus (100%). Although P1 can degrade pyrene independently, other bacteria, such as Novosphingobium sp. (Band 14), Halomonas sp. (Band 16) and an unidentified bacterium (Band 35), were involved in pyrene degradation in some way; they persist in the consortium in the test of dilution to extinction if only the consortium was motivated with pyrene. However, the secondary most important member Flavobacterium sp. evaded from the community at high dilutions. As a key member of the consortium, P1 distinguished itself by both cell morphology and carbon source range among the isolates of this genus. Based on intermediate analyses of pyrene degradation, P1 was supposed to take an upper pathway different from that previously reported. Together with the results of obtained genes from P1 homology with those responsible for naphthalene degradation, its degradation to pyrene is supposed to adopt another set of genes unique to presently detected. Summarily, an efficient pyrene-degrading consortium was obtained from the Pacific Ocean sediment, in which Cycloclasticus bacterium played a key role. This is the first report to exploit the diversity of pyrene-degrading bacteria in oceanic environments. 相似文献
967.
968.
The function of the IFN-stimulated gene family protein, IFN-induced protein with tetratricopeptide repeats 2 (IFIT2), is poorly understood. Here, we report that IFIT2 colocalizes with cytokeratin 18 in oral squamous cell carcinoma (OSCC) cells. Treatment of OSCC cells with IFN-beta significantly increased the expression of IFIT2 and remarkably inhibited cell migration. To further explore the effect of IFIT2 on cell migration, IFIT2 expression was either silenced with a small interfering RNA or increased by ectopic expression. IFIT2 knockdown in OSCC cells led to a significantly higher level of migration in vitro (P < 0.05) compared with control cells; by contrast, IFIT2 overexpression led to a significantly lower level of migration in vitro (P < 0.05). Immunohistochemically, 71.4% of OSCC tissues had elevated IFIT2 protein levels compared with noncancerous matched tissues. Elevated IFIT2 protein expression was positively associated with tumor differentiation status and inversely associated with nodal stage in OSCC specimens (P < 0.05). Higher IFIT2 protein levels in tumor tissues were also associated with better patient survival (P < 0.01). Our present study shows an inverse correlation between IFIT2 expression and cell migration, suggesting that IFIT2 plays an important role in inhibiting this process and that its expression may be associated with better prognosis in patients with OSCC. 相似文献
969.
Pot experiment to study the uptake of Cd and Pb by three Indian mustards (Brassica juncea) grown in artificially contaminated soils 总被引:1,自引:0,他引:1
Most of the metals-contaminated and fallow lands in Taiwan are a result of irrigation with illegal effluent of factories. Phytoextraction methods can be applied to reach the target of fallow-lands reuse and earn more incomes for farmers. In many studies, Indian mustards (Brassica juncea) were planted in the metal-contaminated soils to study their suitability in phytoextraction. However, the total removal of metals by plants was quite different between accessions. In this pot study, three accessions of B. juncea (cv. 182921, cv. 211000, and cv. 426308) were planted in artificially Cd- or Pb-contaminated soils to investigate the differences between them. EDTA was applied to study its effect in increasing the bioavailability of Cd and Pb and their uptake by these Indian mustards. Experimental result showed that three accessions of Indian mustard can accumulate a high concentration of Cd and Pb when growing in the artificially Cd- and Pb-contaminated soils. Their shoot Cd or Pb concentrations were significantly enhanced, resulting from the application of EDTA. Among the three accessions, B. juncea cv. 211000 accumulated the highest concentrations of Cd and Pb in their shoots compared with B. juncea cv. 182921 and cv. 426308, but its total removal was the lowest due to its lower biomass. 相似文献
970.
Cloughesy TF Yoshimoto K Nghiemphu P Brown K Dang J Zhu S Hsueh T Chen Y Wang W Youngkin D Liau L Martin N Becker D Bergsneider M Lai A Green R Oglesby T Koleto M Trent J Horvath S Mischel PS Mellinghoff IK Sawyers CL 《PLoS medicine》2008,5(1):e8