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81.
IntroductionFemale sex workers (FSWs) are at highest risk for contracting HIV and facilitating the current heterosexual HIV epidemic in Guangxi, China, yet little is known of the impact of recent harm reduction campaigns in the province. We analyzed sentinel surveillance data collected between 2010 and 2012 in Guangxi to explore correlations between the prevalence of HIV, hepatitis C (HCV), and syphilis and risk behaviors of different categories of FSWs in Guangxi.MethodsThe sentinel surveillance data for 5,1790 FSWs in all 14 prefectures and 64 city/county regions of Guangxi, China from 2010 to 2012 were collected. Differences between three categories of FSWs (grouped by venue) and disease trends (HIV, HCV, and syphilis) by year were analyzed using bivariate and multivariate logistic regression analyses as to evaluate risk factors correlated with HIV, HCV, or syphilis infection.ResultsHIV and HCV prevalence remained constant across the three FSW categories; however, syphilis prevalence showed a significant increase from 5.7% to 7.3% for low-tier FSWs. Most cases with HIV, HCV, syphilis and intravenous drug use were seen in low-tier FSWs. Testing positive for HIV and syphilis were most correlated with being HCV positive (AOR 4.12 and AOR 4.36), only completing elementary school (AOR 3.71 and AOR 2.35), low tier venues (AOR 2.02 and AOR 2.00), and prior STI (AOR 1.40 and AOR 3.56), respectively. HCV infection was correlated with ever injecting drugs (AOR 60.65) and testing positive for syphilis (AOR 4.16) or HIV (AOR 3.74).ConclusionsThis study highlights that low tier FSWs with lower formal education levels are the most vulnerable population at risk for acquiring and transmitting HIV, HCV, and syphilis in Guangxi, China. Condom distribution with evolution to safer sex practices are the reasons to explain the non-increasing prevalence of HIV, HCV in Guangxi for 2010–2012.  相似文献   
82.

Land-use change has led to substantial range contractions for many species. Such contractions are particularly acute for wide-ranging large carnivores in Asia’s high altitude areas, which are marked by high spatiotemporal variability in resources. Current conservation planning for human-dominated landscapes often takes one of two main approaches: a “coexistence” (land sharing) approach or a “separation” (land sparing) approach. In this study, we evaluated the effects of land-use management on a guild of large carnivores in a montane ecosystem located in northeastern Iran. We used interview surveys to collect data on Persian leopard Panthera pardus saxicolor and grey wolf Canis lupus and modeled the areas occupied by these species in a Bayesian framework. After accounting for imperfect detection, we found that wolves had a higher probability of occupying the study area than leopards (82%; 95% CI 73–90% vs. 63%; 95% CI 53–73%). Importantly, each predator showed contrasting response to land-use management. National Parks (i.e. human-free areas) had a positive association with leopard occupancy (αNational Park?=?2.56, 95% CI 0.22–5.77), in contrast to wolves, which displayed a negative association with National Parks (αNational Park = ? 1.62, 95% CI ? 2.29 to 0.31). An opposite pattern was observed for human-dominated areas (i.e. Protected Areas and Communal Lands), where occupancy was higher for wolves but lower for leopards. Our study suggests that to protect these large carnivores, a combination of land sharing and land sparing approaches is desirable within Iran montane landscapes. Any recovery program for big cats in Iranian mountains, and likely similar mountainous landscapes in west Asia, should take into account other sympatric carnivores and how they can affect adjacent human communities. For example, conflict mitigation and compensation efforts are required to include the guild of large carnivores, instead of solely targeting the charismatic big cats.

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83.
Background

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease. Its etiology remains largely unknown, although frequent concomitant inflammatory bowel disease (IBD) hints towards common factors underlying intestinal and bile duct inflammation. Herein, we aimed to explore the relative abundance of fecal microbiota in PSC-IBD patients compared to IBD-only subjects and controls.

Methods and results

We included 14 PSC-IBD patients, 12 IBD-only patients, and 8 healthy controls (HCs). A quantitative real-time PCR (qPCR) assay was used to determine a selection of bacterial phyla, families, and genera.

Relative abundance of taxa showed that Bacteroidetes was the most abundant phylum among the patients with PSC-IBD (29.46%) and also HCs (39.34%), whereas the bacterial species belonging to the phylum Firmicutes were the most frequent group in IBD-only subjects (37.61%). The relative abundance of the Enterobacteriaceae family in fecal samples of PSC-IBD patients was similar to those with IBD-only, which was significantly higher than HCs (p value?=?0.031), and thus, could be used as a PSC-IBD or IBD-only associated microbial signature.

Conclusions

Our findings showed that intestinal microbiota composition in PSC-IBD patients was completely different from that of IBD-only patients. Further studies using large-scale cohorts should be performed to better describe the contribution of the gut microbiota to PSC pathogenesis with underlying IBD.

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84.

Early-stage gastrointestinal (GI) carcinomas are amenable malignancies, however, due to late diagnosis or lack of proper medication, alternative treatment necessitates new approaches such as dendritic cell (DC) therapy. Our previous microarray study indicated Lymphocyte antigen-6 (LY6E) as a commonly overexpressed biomarker in three lethal GI cancers, colon, gastric, and pancreatic. Therefore, we examined the antigenic potency of LY6E in stimulating DCs to elicit tumor-specific responses against human colorectal cancer (CRC) and gastric cancer (GC) cell lines HT-29 and AGS, respectively. LY6E peptide-pulsed DCs stimulated lymphocytes up to 55.9% in comparison with mature DCs (48.3%). Also, flow cytometry analysis of lymphocyte proliferation illustrated that the populations CD4+ and CD8+ were increased after treating by peptide-pulsed DCs (62.9% and 48.7% respectively). Furthermore, the cytotoxicity assay demonstrated that the 40:1 ratio of stimulated lymphocytes on AGS and HT29 cell lines was 65.1% and 66.2%, respectively. The research exposed that LY6E loaded DCs had substantial impact stimulation, proliferation, and lineage differentiation of lymphocytes. Besides, co-cultured of primed lymphocytes with AGS and HT29 cell lines exhibited cytotoxic activity. These data suggest LY6E as a potential candidate in developing DC therapy against CRC and AGS.

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85.
Lee BH  Liu J  Wong D  Srinivasan S  Ashrafi K 《PLoS biology》2011,9(12):e1001219
Bardet-Biedl syndrome, BBS, is a rare autosomal recessive disorder with clinical presentations including polydactyly, retinopathy, hyperphagia, obesity, short stature, cognitive impairment, and developmental delays. Disruptions of BBS proteins in a variety of organisms impair cilia formation and function and the multi-organ defects of BBS have been attributed to deficiencies in various cilia-associated signaling pathways. In C. elegans, bbs genes are expressed exclusively in the sixty ciliated sensory neurons of these animals and bbs mutants exhibit sensory defects as well as body size, feeding, and metabolic abnormalities. Here we show that in contrast to many other cilia-defective mutants, C. elegans bbs mutants exhibit increased release of dense-core vesicles and organism-wide phenotypes associated with enhanced activities of insulin, neuropeptide, and biogenic amine signaling pathways. We show that the altered body size, feeding, and metabolic abnormalities of bbs mutants can be corrected to wild-type levels by abrogating the enhanced secretion of dense-core vesicles without concomitant correction of ciliary defects. These findings expand the role of BBS proteins to the regulation of dense-core-vesicle exocytosis and suggest that some features of Bardet-Biedl Syndrome may be caused by excessive neuroendocrine secretion.  相似文献   
86.
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88.
To more closely understand the mechanisms of how BCG vaccination confers immunity would help to rationally design improved tuberculosis vaccines that are urgently required. Given the established central role of CD4 T cells in BCG induced immunity, we sought to characterise the generation of memory CD4 T cell responses to BCG vaccination and M. bovis infection in a murine challenge model. We demonstrate that a single systemic BCG vaccination induces distinct systemic and mucosal populations of T effector memory (TEM) cells in vaccinated mice. These CD4+CD44hiCD62LloCD27 T cells concomitantly produce IFN-γ and TNF-α, or IFN-γ, IL-2 and TNF-α and have a higher cytokine median fluorescence intensity MFI or ‘quality of response’ than single cytokine producing cells. These cells are maintained for long periods (>16 months) in BCG protected mice, maintaining a vaccine–specific functionality. Following virulent mycobacterial challenge, these cells underwent significant expansion in the lungs and are, therefore, strongly associated with protection against M. bovis challenge. Our data demonstrate that a persistent mucosal population of TEM cells can be induced by parenteral immunization, a feature only previously associated with mucosal immunization routes; and that these multifunctional TEM cells are strongly associated with protection. We propose that these cells mediate protective immunity, and that vaccines designed to increase the number of relevant antigen-specific TEM in the lung may represent a new generation of TB vaccines.  相似文献   
89.
The zonal rate model (ZRM) has previously been applied for analyzing the performance of axial flow membrane chromatography capsules by independently determining the impacts of flow and binding related non‐idealities on measured breakthrough curves. In the present study, the ZRM is extended to radial flow configurations, which are commonly used at larger scales. The axial flow XT5 capsule and the radial flow XT140 capsule from Pall are rigorously analyzed under binding and non‐binding conditions with bovine serum albumin (BSA) as test molecule. The binding data of this molecule is much better reproduced by the spreading model, which hypothesizes different binding orientations, than by the well‐known Langmuir model. Moreover, a revised cleaning protocol with NaCl instead of NaOH and minimizing the storage time has been identified as most critical for quantitatively reproducing the measured breakthrough curves. The internal geometry of both capsules is visualized by magnetic resonance imaging (MRI). The flow in the external hold‐up volumes of the XT140 capsule was found to be more homogeneous as in the previously studied XT5 capsule. An attempt for model‐based scale‐up was apparently impeded by irregular pleat structures in the used XT140 capsule, which might lead to local variations in the linear velocity through the membrane stack. However, the presented approach is universal and can be applied to different capsules. The ZRM is shown to potentially help save valuable material and time, as the experiments required for model calibration are much cheaper than the predicted large‐scale experiment at binding conditions. Biotechnol. Bioeng. 2013; 110: 1129–1141. © 2012 Wiley Periodicals, Inc.  相似文献   
90.
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