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31.
Zhang Hongling Ran Chao Teame Tsegay Ding Qianwen Hoseinifar Seyed Hossein Xie Mingxu Zhang Zhen Yang Yalin Olsen Rolf Erik Gatlin Delbert M. Ringø Einar Duan Ming Zhou Zhigang 《Reviews in Fish Biology and Fisheries》2020,30(4):569-586
Reviews in Fish Biology and Fisheries - The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a... 相似文献
32.
子宫颈糜烂病毒病因的探讨 总被引:17,自引:0,他引:17
491份宫颈拭子病毒分离结果表明:糜烂宫颈单纯疱疹病毒(HSV)分离阳性率(30.8%)是正常宫颈(2.6%)的11.8倍,用人干扰素治疗一个疗程后,病毒分离率下降至疗前的1/4.36例糜烂宫颈活体组织DNA分子杂交表明,乳头瘤病毒16型(HPV-16)阳性者占52.8和,HPV-18占17.9%,HPV-6B占28.1%,HPV-11占7.7%,251例宫颈糜烂患者经人(?)D型基因工程干扰素双盲对比治疗后,总有效率达93.8%,显效率达60%,分析临床疗效与HSV分离率的变化表明,临床有效病例中有35%(49/140)在治疗后病毒阴转,有57%在疗前疗后均未分离出HSV,有5%在疗前疗后保持阳性不变,有2.9%疗前阴性,疗后阳性,上述结果表明,HSV和HPV与慢性宫颈炎有一定关系。 相似文献
33.
Qu XW Liu WP Qi ZY Duan ZJ Zheng LS Kuang ZZ Zhang WJ Hou YD 《Biochemical and biophysical research communications》2008,365(1):158-163
Human bocavirus (HBoV) is a new parvovirus first discovered in 2005, which is associated with acute respiratory infection. Analysis of sequence homology has revealed that a putative phospholipase A2 (PLA2) motif exists in the VP1 unique region of HBoV. However, little is known about whether the VP1 unique region of HBoV has PLA2 enzymatic activity and how these critical residues contribute to its PLA2 activity. To address these issues, the VP1 unique region protein and four of its mutants, were expressed in Eschericha coli. The purified VP1 unique protein (VP1U) showed a typical Ca2+-dependent secreted PLA2-like (sPLA2) activity, which was inhibited by sPLA2-specific inhibitors in a time-dependent manner. Mutation of one of the amino acids (21Pro, 41His, 42Asp or 63Asp) in VP1U almost eliminated the sPLA2 activity of HBoV VP1U. These data indicate that VP1U of HBoV has sPLA2-like enzymatic activity, and these residues are crucial for its sPLA2-like activity. Potentially, VP1U may be a target for the development of anti-viral drugs for HBoV. 相似文献
34.
Duo Shan Jiangping Sun Anna Yakusik Zhongdan Chen Jianhua Yuan Tao Li Jeannia Fu Kaveh Khoshnood Xing Yang Mei Wei Song Duan Marc Bulterys Michael Sante Runhua Ye Lifen Xiang Yuecheng Yang 《PloS one》2013,8(6)
Objective
We assessed HIV/AIDS expenditures in Dehong Prefecture, Yunnan Province, one of the highest prevalence regions in China, and describe funding sources and spending for different categories of HIV-related interventions and at-risk populations.Methods
2010 HIV/AIDS expenditures in Dehong Prefecture were evaluated based on UNAIDS’ National AIDS Spending Assessment methodology.Results
Nearly 93% of total expenditures for HIV/AIDS was contributed by public sources. Of total expenditures, 52.7% was allocated to treatment and care, 24.5% to program management and administration and 19.8% to prevention. Spending on treatment and care was primarily allocated to the treatment of opportunistic infections. Most (40.4%) prevention spending was concentrated on most-at-risk populations, injection drug users (IDUs), sex workers, and men who have sex with men (MSM), with 5.5% allocated to voluntary counseling and testing. Prevention funding allocated for MSM, partners of people living with HIV and prisoners and other confined populations was low compared to the disproportionate burden of HIV/AIDS in these populations. Overall, people living with HIV accounted for 57.57% of total expenditures, while most-at-risk populations accounted for only 7.99%.Conclusions
Our study demonstrated the applicability of NASA for tracking and assessing HIV expenditure in the context of China, it proved to be a useful tool in understanding national HIV/AIDS response from financial aspect, and to assess the extent to which HIV expenditure matches epidemic patterns. Limited funding for primary prevention and prevention for MSM, prisoners and partners of people living with HIV, signal that resource allocation to these key areas must be strengthened. Comprehensive analyses of regional and national funding strategies are needed to inform more equitable, effective and cost-effective HIV/AIDS resource allocation. 相似文献35.
Haoyu Liang Lin Jiang Qiyun Jiang Jie Shi Jingxi Xiang Xiaohui Yan Xiangcheng Zhu Lixing Zhao Ben Shen Yanwen Duan Yong Huang 《Environmental microbiology》2019,21(11):4270-4282
Acyltransferase (AT)-less type I polyketide synthases (PKSs) produce complex natural products due to the presence of many unique tailoring enzymes. The 3-hydroxy-3-methylglutaryl coenzyme A synthases (HCSs) are responsible for β-alkylation of the growing polyketide intermediates in AT-less type I PKSs. In this study, we discovered a large group of HCSs, closely associated with the characterized and orphan AT-less type I PKSs through in silico genome mining, sequence and genome neighbourhood network analyses. Using HCS-based probes, the survey of 1207 in-house strains and 18 soil samples from different geographic locations revealed the vast diversity of HCS-containing AT-less type I PKSs. The presence of HCSs in many AT-less type I PKSs suggests their co-evolutionary relationship. This study provides a new probe to study the abundance and diversity of AT-less type I PKSs in the environment and microbial strain collections. Our study should inspire future efforts to discover new polyketide natural products from AT-less type I PKSs. 相似文献
36.
Phylogeographic structure and deep lineage diversification of the red alga Chondrus ocellatus Holmes in the Northwest Pacific 下载免费PDF全文
Zi‐Min Hu Jing‐Jing Li Zhong‐Min Sun Jung‐Hyun Oak Jie Zhang Pablo Fresia W. Stewart Grant De‐Lin Duan 《Molecular ecology》2015,24(19):5020-5033
A major goal of phylogeographic analysis using molecular markers is to understand the ecological and historical variables that influence genetic diversity within a species. Here, we used sequences of the mitochondrial Cox1 gene and nuclear internal transcribed spacer to reconstruct its phylogeography and demographic history of the intertidal red seaweed Chondrus ocellatus over most of its geographical range in the Northwest Pacific. We found three deeply separated lineages A, B and C, which diverged from one another in the early Pliocene–late Miocene (c. 4.5–7.7 Ma). The remarkably deep divergences, both within and between lineages, appear to have resulted from ancient isolations, accelerated by random drift and limited genetic exchange between regions. The disjunct distributions of lineages A and C along the coasts of Japan may reflect divergence during isolation in scattered refugia. The distribution of lineage B, from the South China Sea to the Korean Peninsula, appears to reflect postglacial recolonizations of coastal habitats. These three lineages do not coincide with the three documented morphological formae in C. ocellatus, suggesting that additional cryptic species may exist in this taxon. Our study illustrates the interaction of environmental variability and demographic processes in producing lineage diversification in an intertidal seaweed and highlights the importance of phylogeographic approaches for discovering cryptic marine biodiversity. 相似文献
37.
Jun Hu Guohua Lv Shuguang Zhou Yucheng Zhou Bangxu Nie Hong Duan Yunfeng Zhang Xiaofeng Yuan 《PloS one》2015,10(5)
BackgroundOsteosarcoma is the most common primary bone malignancy in children and young adults. Increasing results suggest that discovery of microRNAs (miRNAs) might provide a novel therapeutical target for osteosarcoma.MethodsMiR-182 expression level in osteosarcoma cell lines and tissues were assayed by qRT-PCR. MiRNA mimics or inhibitor were transfected for up-regulation or down-regulation of miR-182 expression. Cell function was assayed by CCK8, migration assay and invasion assay. The target genes of miR-182 were predicated by bioinformatics algorithm (TargetScan Human).ResultsMiR-182 was down-regulated in osteosarcoma tissues and cell lines. Overexpression of miR-182 inhibited tumor growth, migration and invasion. Subsequent investigation revealed that TIAM1 was a direct and functional target of miR-182 in osteosarcoma cells. Overexpression of miR-182 impaired TIAM1-induced inhibition of proliferation and invasion in osteosarcoma cells.ConclusionsDown-expression of miR-182 in osteosarcoma promoted tumor growth, migration and invasion by targeting TIAM1. MiR-182 might act as a tumor suppressor gene whose down-regulation contributes to the progression and metastasis of osteosarcoma, providing a potential therapy target for osteosarcoma patients. 相似文献
38.
Dongsheng Li Bilin Dong Zhongsheng Tong Qinning Wang Weihuang Liu Yan Wang Wei Liu Jinbo Chen Li Xu Liuqing Chen Yiqun Duan 《PloS one》2012,7(12)
Mannan-binding lectin (MBL), a lectin homologous to C1q, greatly facilitates C3/C4-mediated opsonophagocytosis of Candida albicans (C. albicans) by human neutrophils, and has the capacity to bind to CR1 (CD35) expressed on circulating neutrophils. The intracellular pool of neutrophil Dectin-1 plays a critical role in stimulating the reactive oxygen species (ROS) generation through recognition of β-1,3-glucan component of phagocytized zymosan or yeasts. However, little is known about whether MBL can mediate the opsonophagocytosis of Candida albicans by neutrophils independent of complement activation, and whether MBL-mediated opsonophagocytosis influence the intracellular expression of Dectin-1 and ROS production. Here we showed that the inhibited phagocytic efficiency of neutrophils as a result of blockage of Dectin-1 was compensated by exogenous MBL alone in a dose-dependent manner. Furthermore, the expressions of Dectin-1 at mRNA and intracellular protein levels were significantly up-regulated in neutrophils stimulated by MBL-pre-incubated C. albicans, while the expression of surface Dectin-1 remained almost unchanged. Nevertheless, the stimulated ROS production in neutrophils was partly and irreversibly inhibited by blockage of Dectin-1 in the presence of exogenous MBL. Confocal microscopy examination showed that intracellular Dectin-1 was recruited and co-distributed with ROS on the surface of some phagocytized yeasts. The β-1,3-glucanase digestion test further suggested that the specific recognition and binding site of human Dectin-1 is just the β-1,3-glucan moiety on the cell wall of C. albicans. These data demonstrate that MBL has an ability to mediate the opsonophagocytosis of Candida albicans by human neutrophils independent of complement activation, which is coupled with intracellular Dectin-1-triggered ROS production. 相似文献
39.
40.
Faham S Yang D Bare E Yohannan S Whitelegge JP Bowie JU 《Journal of molecular biology》2004,335(1):297-305
The molecular forces that stabilize membrane protein structure are poorly understood. To investigate these forces we introduced alanine substitutions at 24 positions in the B helix of bacteriorhodopsin and examined their effects on structure and stability. Although most of the results can be rationalized in terms of the folded structure, there are a number of surprises. (1) We find a remarkably high frequency of stabilizing mutations (17%), indicating that membrane proteins are not highly optimized for stability. (2) Helix B is kinked, with the kink centered around Pro50. The P50A mutation has no effect on stability, however, and a crystal structure reveals that the helix remains bent, indicating that tertiary contacts dominate in the distortion of this helix. (3) We find that the protein is stabilized by about 1kcal/mol for every 38A(2) of surface area buried, which is quite similar to soluble proteins in spite of their dramatically different environments. (4) We find little energetic difference, on average, in the burial of apolar surface or polar surface area, implying that van der Waals packing is the dominant force that drives membrane protein folding. 相似文献