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281.
Chunyan Chen Tian Shen Fei Tian Ping Lin Qingtian Li Zelin Cui Yajuan Zhang Min Xue Jing Ye Xiaokui Guo YuhuaZhou 《Acta biochimica et biophysica Sinica》2013,(12):1039-1048
Community-acquired pneumonia (CAP) is a major concern in hospitals and the bacterial community of which has not been systemically discussed yet. Sputum from patients in the acute stages is a kind of accessible sample reflecting its fea- tures. In our study, we analyzed 45 sputum samples from 45 patients with CAP. Eighteen sputum samples from healthy people were chosen as the controls. Pyrosequencing of the 16s rDNA V3 hypervariable regions of aH the bacteria con- tained in the sputum was used as a culture-independent method to disclose the community constitution. Also, our published data for hospital-acquired pneumonia (HAP) in sputum was used for comparison. By pyrosequencing, 〉90,000 DNA reads were detected. After being analyzed by tools in the Ribosomal Database Project, the reads were clas- sified into five main phyla and 〉100 genera. At the phyla level, the reads' distribution of CAP is similar to that of healthy people and at genera level, the occurrence of each genus possesses their feature in three categories. Genera such as Streptococcus and Neisseria showed stability in their percentages, indicating that such genera are rarely affected by exogenous bacteria or antibiotics. The role of other genera such as Moraxella and Rothia in CAP should be emphasized. According to our analysis, the bacterial communities of CAP are with slight change when compared with those of healthy people, but have a large gap between HAP. Meanwhile, Rothia might be an important endogenous pneumonia-causing factor. 相似文献
282.
Adam Ahanchédé José E. F. Alfaya L. W. Andersen Didier Azam Ma. Anita M. Bautista Anne‐Laure Besnard Gregorio Bigatti Anthony Bouétard Marie‐Agnès Coutellec Eben‐Ezer B. K. Ewédjè Reiko Fuseya Ricardo GarcÍa‐Jiménez M. Haratian Olivier J. Hardy L.‐E. Holm Casey W. Hoy Eriko Koshimizu V. Loeschcke Violeta López‐Márquez Carlos A. Machado Annie Machordom C. Marchi Andrew P. Michel Claire Micheneau Omprakash Mittapalli Takahiro Nagai Nobuaki Okamoto Ying Pan F. Panitz N. Safaie Takashi Sakamoto B. Sharifnabi En‐Wei Tian Hui Yu 《Molecular ecology resources》2013,13(1):158-159
This article documents the addition of 83 microsatellite marker loci and 96 pairs of single‐nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Bembidion lampros, Inimicus japonicus, Lymnaea stagnalis, Panopea abbreviata, Pentadesma butyracea, Sycoscapter hirticola and Thanatephorus cucumeris (anamorph: Rhizoctonia solani). These loci were cross‐tested on the following species: Pentadesma grandifolia and Pentadesma reyndersii. This article also documents the addition of 96 sequencing primer pairs and 88 allele‐specific primers or probes for Plutella xylostella. 相似文献
283.
Roxanne Dutia Andrea J. Kim Matthew Modes Robert Rothlein Jane M. Shen Ye Edward Tian Jumana Ihbais Sam F. Victory Carmen Valcarce Sharon L. Wardlaw 《PloS one》2013,8(6)
Activation of brain melanocortin-4 receptors (MC4-R) by α-melanocyte-stimulating hormone (MSH) or inhibition by agouti-related protein (AgRP) regulates food intake and energy expenditure and can modulate neuroendocrine responses to changes in energy balance. To examine the effects of AgRP inhibition on energy balance, a small molecule, non-peptide compound, TTP2515, developed by TransTech Pharma, Inc., was studied in vitro and in rodent models in vivo. TTP2515 prevented AgRP from antagonizing α-MSH-induced increases in cAMP in HEK 293 cells overexpressing the human MC4-R. When administered to rats by oral gavage TTP2515 blocked icv AgRP-induced increases in food intake, weight gain and adiposity and suppression of T4 levels. In both diet-induced obese (DIO) and leptin-deficient mice, TTP2515 decreased food intake, weight gain, adiposity and respiratory quotient. TTP2515 potently suppressed food intake and weight gain in lean mice immediately after initiation of a high fat diet (HFD) but had no effect on these parameters in lean chow-fed mice. However, when tested in AgRP KO mice, TTP2515 also suppressed food intake and weight gain during HFD feeding. In several studies TTP2515 increased T4 but not T3 levels, however this was also observed in AgRP KO mice. TTP2515 also attenuated refeeding and weight gain after fasting, an effect not evident in AgRP KO mice when administered at moderate doses. This study shows that TTP2515 exerts many effects consistent with AgRP inhibition however experiments in AgRP KO mice indicate some off-target effects of this drug. TTP2515 was particularly effective during fasting and in mice with leptin deficiency, conditions in which AgRP is elevated, as well as during acute and chronic HFD feeding. Thus the usefulness of this drug in treating obesity deserves further exploration, to define the AgRP dependent and independent mechanisms by which TTP2515 exerts its effects on energy balance. 相似文献
284.
Lingyi Fu Wangbing Chen Wei Guo Jingshu Wang Yun Tian Dingbo Shi Xiaohong Zhang Huijuan Qiu Xiangsheng Xiao Tiebang Kang Wenlin Huang Shusen Wang Wuguo Deng 《PloS one》2013,8(7)
Berberine (BBR), an isoquinoline derivative alkaloid isolated from Chinese herbs, has a long history of uses for the treatment of multiple diseases, including cancers. However, the precise mechanisms of actions of BBR in human lung cancer cells remain unclear. In this study, we investigated the molecular mechanisms by which BBR inhibits cell growth in human non-small-cell lung cancer (NSCLC) cells. Treatment with BBR promoted cell morphology change, inhibited cell migration, proliferation and colony formation, and induced cell apoptosis. Further molecular mechanism study showed that BBR simultaneously targeted multiple cell signaling pathways to inhibit NSCLC cell growth. Treatment with BBR inhibited AP-2α and AP-2β expression and abrogated their binding on hTERT promoters, thereby inhibiting hTERT expression. Knockdown of AP-2α and AP-2β by siRNA considerably augmented the BBR-mediated inhibition of cell growth. BBR also suppressed the nuclear translocation of p50/p65 NF-κB proteins and their binding to COX-2 promoter, causing inhibition of COX-2. BBR also downregulated HIF-1α and VEGF expression and inhibited Akt and ERK phosphorylation. Knockdown of HIF-1α by siRNA considerably augmented the BBR-mediated inhibition of cell growth. Moreover, BBR treatment triggered cytochrome-c release from mitochondrial inter-membrane space into cytosol, promoted cleavage of caspase and PARP, and affected expression of BAX and Bcl-2, thereby activating apoptotic pathway. Taken together, these results demonstrated that BBR inhibited NSCLC cell growth by simultaneously targeting AP-2/hTERT, NF-κB/COX-2, HIF-1α/VEGF, PI3K/AKT, Raf/MEK/ERK and cytochrome-c/caspase signaling pathways. Our findings provide new insights into understanding the anticancer mechanisms of BBR in human lung cancer therapy. 相似文献
285.
Granulocyte colony-stimulating factor (G-CSF) induces stem cells to mobilize to the injury site, which have beneficial effect on tissue repair. The aim of this study was to investigate the effect of G-CSF on the thin endometrium in rat models. In the present study, rats with thin endometrium were divided into 4 groups (experimental group I: administrated with G-CSF (40 µg/kg/d) 4–6 hours post-modeling; control group I: administrated with saline 4–6 hours post-modeling; experimental group II: administrated with G-CSF (40 µg/kg/d) 12 days post-modeling; control group II: administrated with saline 12 days post-modeling. The agentia was given once daily and last for 5 days. Endometrial morphology was analyzed by Hematoxylin-Eosin staining, and the regeneration of endometrial cells was evaluated by immunohistochemistry and western-blot with cytokeratin and vimentin. We found that endometrial thickness and morphology presented a significant difference between experimental groups and control groups. No matter when we start with G-CSF, there was a significantly thicker endometrium and stronger expression of cytokeratin/vimintin in the experimental groups compared with the control groups (P<0.01). There were significant thicker endometrial lining and stronger expression of cytokeratin/vimintin in experimental group I than that of experimental group II (P<0.05), but there was no difference in the endometrial lining and the expression of cytokeratin/vimintin between the two control groups (P>0.05). In conclusion, G-CSF can promote the regeneration of endometrial cells in animal research, especially when the G-CSF was administrated earlier. 相似文献
286.
Background
Predicting protein subnuclear localization is a challenging problem. Some previous works based on non-sequence information including Gene Ontology annotations and kernel fusion have respective limitations. The aim of this work is twofold: one is to propose a novel individual feature extraction method; another is to develop an ensemble method to improve prediction performance using comprehensive information represented in the form of high dimensional feature vector obtained by 11 feature extraction methods.Methodology/Principal Findings
A novel two-stage multiclass support vector machine is proposed to predict protein subnuclear localizations. It only considers those feature extraction methods based on amino acid classifications and physicochemical properties. In order to speed up our system, an automatic search method for the kernel parameter is used. The prediction performance of our method is evaluated on four datasets: Lei dataset, multi-localization dataset, SNL9 dataset and a new independent dataset. The overall accuracy of prediction for 6 localizations on Lei dataset is 75.2% and that for 9 localizations on SNL9 dataset is 72.1% in the leave-one-out cross validation, 71.7% for the multi-localization dataset and 69.8% for the new independent dataset, respectively. Comparisons with those existing methods show that our method performs better for both single-localization and multi-localization proteins and achieves more balanced sensitivities and specificities on large-size and small-size subcellular localizations. The overall accuracy improvements are 4.0% and 4.7% for single-localization proteins and 6.5% for multi-localization proteins. The reliability and stability of our classification model are further confirmed by permutation analysis.Conclusions
It can be concluded that our method is effective and valuable for predicting protein subnuclear localizations. A web server has been designed to implement the proposed method. It is freely available at http://bioinformatics.awowshop.com/snlpred_page.php. 相似文献287.
This paper describes a newly devised autosomal short tandem repeat (STR) multiplex polymerase chain reaction (PCR) systems for 17 autosomal loci (D1S1656, D2S441, D3S1358, D3S3045, D6S477, D7S3048, D8S1132, D10S1435, D10S1248, D11S2368, D13S325, D14S608, D15S659, D17S1290, D18S535, D19S253 and D22-GATA198B05) and Amelogenin. Primers for the loci were designed and optimized so that all of the amplicons were distributed from 50 base pairs (bp) to less than 500 bp within a five-dye chemistry design with the fifth dye reserved for the sizing standard. Strategies were developed to overcome challenges that encountered in creating the final assay. The limits of the multiplex were tested, resulting in the successful amplification of genomic DNA range from 0.25–4 ng with 30 PCR cycles. A total of 681 individuals from the Chinese Han population were studied and forensic genetic data were present. No significant deviations from Hardy–Weinberg equilibrium were observed. A total of 180 alleles were detected for the 17 autosomal STRs. The cumulative mean exclusion chance in duos (CMECD) was 0.999967, and cumulative mean exclusion chance in trios (CMECT) was 0.99999995. We conclude that the present 17plex autosomal STRs assay provides an additional powerful tool for forensic applications. 相似文献
288.
Tiejun Zhang Xiuhong Tian Fuchang Ma Ying Yang Feng Yu Yanping Zhao Meiyang Gao Yingying Ding Qingwu Jiang Na He 《PloS one》2013,8(4)
Objective
Voluntary counseling and testing (VCT) plays an important integral role in response to the HIV/AIDS epidemic. However, VCT service has not been effectively utilized among rural migrants, a high risk group in China. In this study, we developed a community based intervention to examine if community mobilization with comprehensive VCT is more effective than current HIV preventions with routine VCT service in promoting VCT acceptability among rural migrants in Shanghai, China.Methods
A comprehensive intervention with community mobilization and comprehensive VCT services including community-based VCT and mobile VCT was implemented during 2007–2009. Three communities in Minhang District of Shanghai were randomly selected and were designed to receive community mobilization and comprehensive VCT, traditional VCT and none intervention, respectively. After 24 months intervention, effects were evaluated by comparing outcome indicators between the baseline (2,690 participants) and follow-up surveys (1,850 participants).Findings
A substantial increase in VCT acceptance was observed among community mobilization group (94.9% vs. 88.5%, P<0.001), whereas the reverse effect was seen in the traditional VCT group (86.1% vs. 94.6%, P<0.001) and control group (69.0% vs. 91.7%, P<0.001). Rural migrants from community mobilization group were more likely to accept VCT (OR = 2.91, 95% CI 1.69–4.97). Rural migrants from community mobilization group also showed significant increase in HIV/AIDS knowledge, positive attitude towards HIV positive individuals and condom use.Conclusion
Community mobilization with comprehensive VCT has significant impact on promotion of VCT acceptance and utilization among rural migrants in Shanghai. These findings provide evidence to support community mobilization as a suitable strategy for VCT promotion among rural migrants in Shanghai, China. 相似文献289.
Tryptase, the most abundant mast cell (MC) granule protein, plays an important role in atherosclerosis plaque development. To test the hypothesis that tryptase participates directly in atherosclerosis plaque haemorrhage, the gene sequence and siRNA for tryptase were cloned into a lentivirus carrier and atherosclerosis plaque haemorrhage models in ApoE-/- mice were constructed. After a cuffing-cervical artery operation, the mice were randomly divided into 6 groups. Hematoxylin and eosin(HE) staining showed that the cervical artery plaque area was much larger in the tryptase overexpression group compared to the other groups, and there was greater artery stenosis. The artery stenosis from the cuff-side in all groups was more than 90%, except the siRNA group. Tryptase promotes plaque haemorrhage distinctively because 50% of the mice in the tryptase overexpression group had plaque haemorrhage, while only 10% in the siRNA group did. The immunohistochemistry of the cervical artery plaque showed that plasminogen activator inhibitor-1 (PAI-1) expression was the lowest while tissue plasminogen activator (tPA), CD31, CD34 and VEGF was the highest in the tryptase overexpression groups. This observation was completely contrary to what was observed in the siRNA group. Tryptase promoted bEnd.3 cell growth, migration and capillary-like tube formation, which suggests that tryptase can promote microvessel angiogenesis. PAI-1 expression was inhibited, while tPA expression was increased by tryptase in bEnd.3 cells. Our in vivo and in vitro studies suggest that trypase can promote atherosclerotic plaque haemorrhage by promoting angiogenesis and regulating the balance of PAI-1 and tPA. Thus, regulating tryptase expression in MCs may provide a potential target for atherosclerosis treatment. 相似文献
290.
Xiao Wei Xin Chen Xia Wang Weiwei Zheng Dong Zhang Dajun Tian Songhui Jiang Choon Nam Ong Gengsheng He Weidong Qu 《PloS one》2013,8(3)
Drinking water chlorination plays a pivotal role in preventing pathogen contamination against water-borne disease. However, chemical disinfection leads to the formation of halogenated disinfection by products (DBPs). Many DBPs are highly toxic and are of health concern. In this study, we conducted a comprehensive measurements of DBPs, including iodoacetic acid (IAA), iodoform (IF), nine haloacetic acids and four trihalomethanes in drinking waters from 13 water plants in Shanghai, China. The results suggested that IAA and IF were found in all the water treatment plants, with maximum levels of 1.66 µg/L and 1.25 µg/L for IAA and IF, respectively. Owing to deterioration of water quality, the Huangpu River has higher IAA and IF than the Yangtze River. Our results also demonstrated that low pH, high natural organic matter, ammonia nitrogen, and iodide in source waters increased IAA and IF formation. Compared to chlorine, chloramines resulted in higher concentration of iodinated DBP, but reduced the levels of trihalomethanes. This is the first study to reveal the widespread occurrence of IAA and IF in drinking water in China. The data provide a better understanding on the formation of iodinated disinfection byproducts and the findings should be useful for treatment process improvement and disinfection byproducts controls. 相似文献