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991.
Our goal was to establish a quantitative real-time PCR (QRT-PCR) method to detect Bacteroides fragilis group and related organisms from clinical specimens. Compared to conventional anaerobic culture, QRT-PCR can provide accurate and more rapid detection and identification of B.?fragilis group and similar species. B.?fragilis group and related organisms are the most frequently isolated anaerobic pathogens from clinical samples. However, culture and phenotypic identification is quite time-consuming. We designed specific primers and probes based on the 16S rRNA gene sequences of Bacteroides caccae, Bacteroides eggerthii, B.?fragilis, Bacteroides ovatus, Bacteroides stercoris, Bacteroides thetaiotaomicron, Bacteroides uniformis, Bacteroides vulgatus, Odoribacter splanchnicus (Bacteroides splanchnicus), Parabacteroides distasonis (Bacteroides distasonis) and Parabacteroides merdae (Bacteroides merdae), and detected these species by means of QRT-PCR in 400 human surgical wound infection samples or closed abscesses. The target bacteria were detected from 31 samples (8%) by culture, but from 132 samples (33%) by QRT-PCR (p-value?0.001). B.?uniformis was the most common species (44 positive samples) according to QRT-PCR while culture showed it to be B.?fragilis (16 positive samples). Additionally, for each species QRT-PCR detected higher counts than culture did; this may reflect detecting DNA of dead organisms by QRT-PCR. QRT-PCR is a rapid and sensitive method which has great potential for detection of B.?fragilis group and related organisms in wound samples. 相似文献
992.
993.
Chen JG Xia JC Liang XT Pan K Wang W Lv L Zhao JJ Wang QJ Li YQ Chen SP He J Huang LX Ke ML Chen YB Ma HQ Zeng ZW Zhou ZW Chang AE Li Q 《International journal of biological sciences》2011,7(1):53-60
In this study, we characterized the intratumoral expression of IL-17 and CD8(+) TILs in gastric adenocarcinoma patients after resection and determined the correlation between the survival probability of gastric adenocarcinoma patients and the expression of IL-17 in tumor. Expression of IL-17 and CD8 was assessed by immunohistochemistry, and the prognostic effects of intratumoral IL-17 expression and CD8(+) TILs were evaluated by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection revealed the presence of IL-17 and CD8(+) cells in gastric adenocarcinoma tissue samples (90.6%, 174 out of 192 patients and 96.9%, 186 out of 192 patients, respectively). We have also found that intratumoral IL-17 expression was significantly correlated with age (p=0.004) and that the number of CD8(+)TILs was significantly correlated with UICC staging (p=0.012) and the depth of tumor invasion (p=0.022). The five-year overall survival probability among patients intratumorally expressing higher levels of IL-17 was significantly better than those expressing lower levels of IL-17 (p=0.036). Multivariate Cox proportional hazard analyses revealed that intratumoral IL-17 expression (HR: 0.521; 95% CI: 0.329-0.823; p=0.005) was an independent factor affecting the five-year overall survival probability. We conclude that low levels of intratumoral IL-17 expression may indicate poor prognosis in gastric adenocarcinoma patients. 相似文献
994.
Genetic, proteomic and metabolic analysis of the regulation of energy storage in rice seedlings in response to drought 总被引:1,自引:0,他引:1
We used proteomic analysis to determine the response of rice plant seedlings to drought-induced stress. The expression of 71 protein spots was significantly altered, and 60 spots were successfully identified. The greatest down-regulated protein functional category was translation. Up-regulated proteins were mainly related to protein folding and assembly. Additionally, many proteins involved in metabolism (e.g. carbohydrate metabolism) also showed differences in expression. cDNA microarray and GC-MS analysis showed 4756 differentially expressed mRNAs and 37 differentially expressed metabolites. Once these data were integrated with the proteomic analysis, we were able to elucidate the metabolic pathways affected by drought-induced stress. These results suggest that increased energy consumption from storage substances occurred during drought. In addition, increased expression of the enzymes involved in anabolic pathways corresponded with an increase in the content of six amino acids. We speculated that energy conversion from carbohydrates and/or fatty acids to amino acids was increased. Analysis of basic metabolism networks allowed us to understand how rice plants adjust to drought conditions. 相似文献
995.
You J Wang L Saji M Olesik SV Ringel MD Lucas DM Byrd JC Freitas MA 《Proteomics》2011,11(16):3326-3334
The analysis of proteins by RPLC commonly involves the use of TFA as an ion‐pairing agent, even though it forms adducts and suppresses sensitivity. The presence of adducts can complicate protein molecular weight assignment especially when protein isoforms coelute as in the case of histones. To mitigate the complicating effects of TFA adducts in protein LC‐MS, we have optimized TFA‐free methods for protein separation. Protein standards and histones were used to evaluate TFA‐free separations using capillary (0.3 mm id) and nanoscale (0.1 mm id) C8 columns with the ion‐pairing agents, formic acid or acetic acid. The optimized method was then used to examine the applicability of the approach for histone characterization in human cancer cell lines and primary tumor cells from chronic lymphocytic leukemia patients. 相似文献
996.
997.
妊娠肝内胆汁淤积症(Intrahepatic cholestasis of pregnancy, ICP)是发生在妊娠中晚期,以皮肤瘙瘁、黄疸、血清胆汁酸升高,伴轻度肝功能损害为特征的妊娠并发症,严重影响母儿健康。ICP的发病机制尚未完全阐明,但有研究表明在遗传易感性妇女中,性激素及其代谢产物导致胆汁酸代谢异常与本病的发生密切相关。现就目前国内外有关ICP发病机制的研究进展做一综述,一方面为探寻更深层次的机制提供理论基础,另一方面为临床治疗ICP提供思路和方法。 相似文献
998.
999.
Background
Accumulating epidemiological evidence shows that life event stressors are major vulnerability factors for psychiatric diseases such as major depression. It is also well known that social isolation in male mice results in aggressive behavior. However, it is not known how social isolation-induced aggression affects anxiety and depressive-like behavior in isolated male mice subjected to unpredictable chronic mild stress (CMS), an animal model of depression.Methodology/Principal Findings
C57/B6 male mice were divided into 3 groups; non-stressed controls, in Group I; isolated mice subjected to the CMS protocol in Group II and aggression by physical contact in socially isolated mice subjected to the CMS protocol in Group III. In the sucrose intake test, ingestion of a 1% sucrose solution by mice in Groups II and III was significantly lower than in Group I. Furthermore, intake of this solution in Group III mice was significantly lower than in Group II mice. In the open field test, mice in Group III, showed reduced locomotor activity and reduced entry and retention time in the central zone, compared to Groups I and II mice. Moreover, the distances moved in 1 hour by Group III mice did not differ between night and morning. In the light/black box test, Groups II and III animals spent significantly less time in the light box compared to Group I animals. In the tail suspension test (TST) and forced swimming test (FST), the immobility times of Group II and Group III mice were significantly longer than in Group I mice. In addition, immobility times in the FST were significantly longer in Group III than in Group II mice.Conclusions/Significance
These findings show that social isolation-induced aggression could potentiate anxiety and depressive -like behaviors in isolated male mice subjected to CMS. 相似文献1000.
Li Y Fu L Wong AM Fan YH Li MX Bei JX Jia WH Zeng YX Chan D Cheung KM Sham P Chua D Guan XY Song YQ 《PloS one》2011,6(1):e14562
Nasopharyngeal carcinoma (NPC) is a malignancy of epithelial origin. The etiology of NPC is complex and includes multiple genetic and environmental factors. We employed case-control analysis to study the association of chromosome 6p regions with NPC. In total, 360 subjects and 360 healthy controls were included, and 233 single nucleotide polymorphisms (SNPs) on 6p were examined. Significant single-marker associations were found for SNPs rs2267633 (p = 4.49 × 10(-5)), rs2076483 (most significant, p = 3.36 × 10(-5)), and rs29230 (p=1.43 × 10(-4)). The highly associated genes were the gamma-amino butyric acid B receptor 1 (GABBR1), human leukocyte antigen (HLA-A), and HLA complex group 9 (HCG9). Haplotypic associations were found for haplotypes AAA (located within GABBR1, p-value = 6.46 × 10(-5)) and TT (located within HLA-A, p = 0.0014). Further investigation of the homozygous genotype frequencies between cases and controls suggested that micro-deletion regions occur in GABBR1 and neural precursor cell expressed developmentally down-regulated 9 (NEDD9). Quantitative real-time polymerase chain reaction (qPCR) using 11 pairs of NPC biopsy samples confirmed the significant decline in GABBR1 and NEDD9 mRNA expression in the cancer tissues compared to the adjacent non-tumor tissue (p<0.05). Our study demonstrates that multiple chromosome 6p susceptibility loci contribute to the risk of NPC, possibly though GABBR1 and NEDD9 loss of function. 相似文献