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991.
The human skin harbors complex bacterial communities. Prior studies showing high inter-individual variation focused on subjects from developed countries. We therefore compared cutaneous bacterial communities of Amerindians in the Venezuelan Amazon with subjects in the United States. Forearm skin specimens were studied from healthy Amerindians in Platanillal village in Amazonas State, and from healthy persons in New York and Colorado. All skin sampling used similar swab/buffer techniques. Multiplexed V2-targeted 16S rRNA gene pyrosequencing yielded high quality sequences from 112 samples. The results show 20 phyla, with three (Proteobacteria, Firmicutes, Actinobacteria) predominating. US residents and Venezuelan Amerindians had significantly different forearm skin bacterial community compositions, with United States dominated by Propionibacterium. Among the Amerindians, there was a deep split based on bacterial community membership, with 30 and 42 samples, respectively, falling into each of the two groups, not associated with age, gender, or body mass index. One Amerindian group had diversity similar to the United States, but was dominated by Staphylococcus rather than Propionibacterium. The other Amerindian group was significantly more diverse and even than the US or the other Amerindian group, and featured a broad range of Proteobacteria. The results provide evidence that ethnicity, lifestyle and/or geography are associated with the structure of human cutaneous bacterial communities.  相似文献   
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993.
Alcoholic liver disease (ALD) is a serious fiver problem in western countries. Our previous study has demonstrated that vitamin C plays a protective role in ALD. The vitamin C homeostasis is tightly regulated by sodium-dependent vitamin C transporters (SVCTs) 1 and 2. But the role of two SVCTs in ALD is less understood. In this study, we exam- ined the expression patterns of two SVCTs in mice after alcohol consumption. Our results suggested that alcohol con- sumption obviously increased the expression of two SVCTs in liver and SVCT1 in kidney and intestine, which is important for vitamin C absorption. Vitamin C supplement increased the sera vitamin C content and ameliorated the symptom of ALD. Intestinal absorption and renal re-absorption mediated by SVCTI are key factors to increase the sera vitamin C content after alcohol consumption. We proposed that both reactive oxygen species and low vitamin C concentration regulate the expression of SVCTs, and the protective role of vitamin C is mediated by suppressing the stability of hypoxia-inducible factor-loL. Thus, our study is significant for the understanding of vitamin C homeostasis in ALD and for better use of other antioxidants in ALD therapy.  相似文献   
994.
For successful therapy, hepatocellular carcinoma (HCC) must be detected at an early stage. Herein, we used a proteomic approach to analyze the secretory/releasing proteome of HCC tissues to identify plasma biomarkers. Serum-free conditioned media (CM) were collected from primary cultures of cancerous tissues and surrounding noncancerous tissues. Proteomic analysis of the CM proteins permitted the identification of 1365 proteins. The enriched molecular functions and biological processes of the CM proteins, such as hydrolase activity and catabolic processes, were consistent with the liver being the most important metabolic organ. Moreover, 19% of the proteins were characterized as extracellular or membrane-bound. For validation, secretory proteins involved in transforming growth factor-β signaling pathways were validated in plasma samples. Alphafetoprotein (AFP), metalloproteinase (MMP)1, osteopontin (OPN), and pregnancy-specific beta-1-glycoprotein (PSG)9 were significantly increased in HCC patients. The overall performance of MMP1 and OPN in the diagnosis of HCC remained greater than that of AFP. In addition, this study represents the first report of MMP1 as a biomarker with a higher sensitivity and specificity than AFP. Thus, this study provides a valuable resource of the HCC secretome with the potential to investigate serological biomarkers. MMP1 and OPN could be used as novel biomarkers for the early detection of HCC and to improve the sensitivity of biomarkers compared with AFP.  相似文献   
995.
Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and reduction in fertilizer input achievable by using high-yielding and nutrient-efficient cultivars is unclear.In the present study,we evaluated the yield and nitrogen use efficiency(NUE) of 40 commercial maize hybrids at five locations in North and Northeast China in 2008 and 2009.The effect of interaction between genotype and nitrogen(N) input on maize yield was significant when the yield reduction under low-N treatment was 25%-60%.Based on the average yields achieved with high or low N application,the tested cultivars were classified into four types based on their NUE:efficient-efficient(EE) were efficient under both low and high N inputs,high-N efficient(HNE) under only high N input,low-N efficient(LNE) under only low N input,and nonefficient-nonefficient under neither low nor high N inputs.Under high N application,EE and HNE cultivars could potentially increase maize yield by 8%-10% and reduce N input by 16%-21%.Under low N application,LNE cultivars could potentially increase maize yield by 12%.We concluded that breeding for N-efficient cultivars is a feasible strategy to increase maize yield and/or reduce N input.  相似文献   
996.
Duck egg drop syndrome virus(DEDSV) is a newly emerging pathogenic flavivirus isolated from ducks in China.DEDSV infection mainly results in severe egg drop syndrome in domestic poultry,which leads to huge economic losses.Thus,the discovery of ways and means to combat DEDSV is urgent.Since 2010,a remarkable amount of progress concerning DEDSV research has been achieved.Here,we review current knowledge on the epidemiology,symptomatology,and pathology of DEDSV.A detailed dissection of the viral genome and polyprotein sequences,comparative analysis of viral antigenicity and the corresponding potential immunity against the virus are also summarized.Current findings indicate that DEDSV should be a distinct species from Tembusu virus.Moreover,the adaption of DEDSV in wildlife and its high homology to pathogenic flaviviruses(e.g.,West Nile virus,Japanese encephalitis virus,and dengue virus),illustrate its reemergence and potential to become a zoonotic pathogen that should not be overlooked.Detailed insight into the antigenicity and corresponding immunity against the virus is of clear significance for the development of vaccines and antiviral drugs specific for DEDSV.  相似文献   
997.
998.
999.
Artemisinin is an endoperoxide sesquiterpene lactone isolated from the aerial parts of Artemisia annua L., and is presently the most potent anti-malarial drug. Owing to the low yield of artemisinin from A. annua as well as the widespread application of artemisinin-based combination therapy recommended by the World Health Organization, the global demand for artemisinin is substantially increasing and is therefore rendering artemisinin in short supply. An economical way to increase artemisinin production is to increase the content of artemisinin in A. annua. In this study, three key genes in the artemisinin biosynthesis pathway, encoding farnesyl diphosphate synthase, amorpha-4, 11-diene C-12 oxidase and its redox partner cytochrome P450 reductase, were over-expressed in A. annua through Agrobacterium-mediated transformation. The transgenic lines were confirmed by Southern blotting and the over-expressions of the genes were demonstrated by real-time PCR assays. The HPLC analysis showed that the artemisinin contents in transgenic lines were increased significantly, with the highest one found to be 3.6-fold higher (2.9 mg/g FW) than that of the control. These results demonstrate that multigene engineering is an effective way to enhance artemisinin content in A. annua.  相似文献   
1000.

Objective

To examine alcohol use and subsequent HIV risky behaviors among a sample of predominately ethnic minority people living with HIV/AIDS (PLWHA) in a rural community in Yunnan Province, China.

Method

A cross-sectional study with a face-to-face questionnaire interview was conducted among eligible participants.

Results

In total, 455 (94.4%) out of 482 eligible HIV patients participated in the study. Of them, 82.6% were ethnic minorities; 15.4% were never married; 96.5% were sexually experienced; 55.4% had used drugs, 67% were receiving antiretroviral therapy (ART). Over 65% were ever drinkers; of whom 61.5% were current drinkers. Among current drinkers, 32.4% drank daily and 41.2% were hazardous drinkers. Chinese white wine was the preferred choice. Higher level of alcohol use among drinkers in the preceding month was positively associated with being males (OR = 2.76, 95%CI: 1.03–7.43), ethnic minorities (OR Jingpo = 2.21, 95%CI: 1.06–4.59; OR other minorities = 3.20, 95%CI: 1.34–7.62), higher education (OR1–6 = 1.98, 95%CI: 0.99–3.96; OR≥7 = 2.35, 95%CI: 1.09–5.06) and being ART-naive (OR = 2.69, 95%CI: 1.67–4.32). About 39% of ever drinkers reported having engaged in sex after drinking since HIV diagnosis. Those who were younger than 46 years (OR16–25 = 7.77, 95%CI: 1.22–49.60, OR26–35 = 2.79, 95%CI: 1.06–7.35, OR36–45 = 2.96, 95%CI: 1.57–7.58), hazardous drinkers (OR = 1.99, 95%CI: 1.00–3.97) and drug users (OR = 3.01, 95%CI: 1.19–7.58) were more likely to have had sex after drinking. Approximately 56% of drug users had used drugs after drinking.

Conclusions

High prevalence of alcohol use and subsequent risky behaviors including sexual engagement and drug use among HIV patients in rural Yunnan require tremendous and integrated efforts for prevention and control of alcohol and drug abuse and HIV spreading.  相似文献   
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