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981.
982.
Xiao Na Wang Ze Song Li Yu Ren Tao Jiang Ya Qing Wang Min Chen Jun Zhang Jian Xiu Hao Yan Bo Wang Ri Na Sha Yi Huang Xiao Liu Jing Chu Hu Guang Qing Sun Hong Gang Li Cheng Liang Xiong Jun Xie Zhi Mao Jiang Zhi Ming Cai Jun Wang Jian Wang Vicki Huff Yao Ting Gui Fei Gao 《PLoS genetics》2013,9(8)
Azoospermia is one of the major reproductive disorders which cause male infertility in humans; however, the etiology of this disease is largely unknown. In the present study, six missense mutations of WT1 gene were detected in 529 human patients with non-obstructive azoospermia (NOA), indicating a strong association between WT1 mutation and NOA. The Wilms tumor gene, Wt1, is specifically expressed in Sertoli cells (SCs) which support spermatogenesis. To examine the functions of this gene in spermatogenesis, Wt1 was deleted in adult testis using Wt1flox and Cre-ERTM mice strains. We found that inactivation of Wt1 resulted in massive germ cell death and only SCs were present in most of the seminiferous tubules which was very similar to NOA in humans. In investigating the potential mechanism for this, histological studies revealed that the blood–testis barrier (BTB) was disrupted in Wt1 deficient testes. In vitro studies demonstrated that Wt1 was essential for cell polarity maintenance in SCs. Further studies found that the expression of cell polarity associated genes (Par6b and E-cadherin) and Wnt signaling genes (Wnt4, Wnt11) were downregulated in Wt1 deficient SCs, and that the expression of Par6b and E-cadherin was regulated by Wnt4. Our findings suggest that Wt1 is important in spermatogenesis by regulating the polarity of SCs via Wnt signaling pathway and that WT1 mutation is one of the genetic causes of NOA in humans. 相似文献
983.
Chao Li Adam Schmidt Eran Pichersky Feng Shi A. Daniel Jones 《Metabolomics : Official journal of the Metabolomic Society》2013,9(1):92-101
Discrimination of isomeric methylated metabolites is an important step toward identifying genes responsible for methylation, but presents substantial challenges because authentic standards are often unavailable and mass spectra of isomers have been considered indistinguishable. In this report, an approach is described for identifying methyl group positions in multiply methylated flavonoid metabolites using combinations of tandem mass spectrometry, liquid chromatography retention, and site-selective methylation by recombinant O-methyltransferases from Solanum habrochaites LA1777. The basis for observed fragment ions in tandem mass spectra of multiply methylated myricetin was further established using enzymatic incorporation of deuterium-labeled methyl groups using S-adenosylmethionine-d 3 as precursor. 相似文献
984.
John Draper Amanda J. Lloyd Royston Goodacre Manfred Beckmann 《Metabolomics : Official journal of the Metabolomic Society》2013,9(1):4-29
Producing a comprehensive overview of the chemical content of biologically-derived material is a major challenge. Apart from ensuring adequate metabolome coverage and issues of instrument dynamic range, mass resolution and sensitivity, there are major technical difficulties associated with data pre-processing and signal identification when attempting large scale, high-throughput experimentation. To address these factors direct infusion or flow infusion electrospray mass spectrometry has been finding utility as a high throughput metabolite fingerprinting tool. With little sample pre-treatment, no chromatography and instrument cycle times of less than 5 min it is feasible to analyse more than 1,000 samples per week. Data pre-processing is limited to aligning extracted mass spectra and mass-intensity matrices are generally ready in a working day for a month’s worth of data mining and hypothesis generation. ESI-MS fingerprinting has remained rather qualitative by nature and as such ion suppression does not generally compromise data information content as originally suggested when the methodology was first introduced. This review will describe how the quality of data has improved through use of nano-flow infusion and mass-windowing approaches, particularly when using high resolution instruments. The increasingly wider availability of robust high accurate mass instruments actually promotes ESI-MS from a merely fingerprinting tool to the ranks of metabolite profiling and combined with MS/MS capabilities of hybrid instruments improved structural information is available concurrently. We summarise current applications in a wide range of fields where ESI-MS fingerprinting has proved to be an excellent tool for “first pass” metabolome analysis of complex biological samples. The final part of the review describes a typical workflow with reference to recently published data to emphasise key aspects of overall experimental design. 相似文献
985.
Hirak Der-Torossian Scott A. Asher Jason H. Winnike Ashley Wysong Xiaoying Yin Monte S. Willis Thomas M. O’Connell Marion E. Couch 《Metabolomics : Official journal of the Metabolomic Society》2013,9(3):730-739
Despite recent consensus definitions, lack of specific biomarkers remains a hurdle towards a more accurate and efficient diagnosis of cancer cachexia, distinguishing cachexia as a separate entity from other wasting syndromes. In a previous pilot study, we have shown that cancer-cachectic mice have a unique metabolic fingerprint with distinct glucose and lipid alterations compared to healthy controls. Further metabolomics studies were carried out to investigate differences in metabolic profiles of cancer-cachectic mice to tumor-bearing non-cachectic mice, calorie-restricted mice, and surgically treated cancer-cachectic mice. CD2F1 mice were divided into: (1) Cachexia Group received cachexia-inducing C26 undifferentiated colon carcinoma cells; (2) Tumor-Burden Group received, non-cachectic, P388 lymphoma cells; (3) Caloric-Restriction Group, remaining cancer-free, but subjected to caloric-restriction; (4) Surgery Group, similar to Cachexia Group, but tumors resected mid-experiment; and (5) Control Group aged intact. Baseline, mid-experiment and final serum samples were collected for 1H NMR spectroscopic analysis. After data reduction, unsupervised principal component analysis and orthogonal projections to latent structures analyses demonstrate that the unique metabolic fingerprint is independent of tumor-burden and distinct from profiles of caloric-restriction and aging. Hyperlipidemia, hyperglycemia, and reduced branched-chain amino acids distinguish cachexia from other groups. Furthermore, the profile of surgically treated mice differs from that of cachectic mice, reverting to a profile more congruent with healthy controls indicating cachexia is amenable to correction where surgical cure is possible. That metabolomic analysis of murine serum is able to differentiate cachexia from tumor-burden and caloric-restriction warrants similar translational investigations in patients to explore cancer cachexia’s unique biomarkers. 相似文献
986.
目的:基于基因拷贝数变异(CNV)区域网络识别神经胶质瘤的重要功能区域。方法:运用独特的计算样本的共相关性值的方法,使CNV数据与基因数据产生联系;基于蛋白质互作关系,在CNV区域与基因之间搭建桥梁,构建CNV区域网络;分析网络拓扑性质,识别出神经胶质瘤的重要功能CNV区域。结果:本文共识别出了11个与神经胶质瘤相关的候选重要功能CNV区域,通过功能注释和通路分析,确认了识别到的区域与神经胶质瘤有重要联系。结论:通过基因与表型之间的联系,利用已知表型基因在同源、功能、互作、结构域上的特征将CNV区域与基因联系起来,通过基因的功能可以了解到CNV区域的功能,对于疾病的预测和诊断有重要的意义。 相似文献
987.
目的:调查入伍新兵心理卫生服务状况及对心理卫生服务的需求。方法:采用质性研究和量性研究相结合的方法,对42名入伍新兵作半结构性访谈,编制《部队心理卫生服务状况和需求》调查表,采用调查表对1609名新兵进行调查。结果:9.4%的新兵心理健康知识比较了解;接近半数新兵(43.5%)对心理健康知识很感兴趣;新兵获取心理知识的途径依次为网络、心理知识讲座、报刊杂志、广播电视、面对面咨询;新兵最期望获得的心理知识依次为如何调节自己的情绪、如何建立良好的人际关系、如何塑造自己的个性和常见的心理障碍表现;新兵认为最有帮助的心理服务形式依次为一对一心理咨询、心理知识讲座、心理测验和团体心理活动;只有7.7%的新兵接受过心理卫生服务。结论:新兵对心理健康知识感兴趣,但认知度和利用度均较低,应通过网络、心理知识讲座等方式普及新兵需要的心理健康知识。 相似文献
988.
In order to evaluate the early tolerance of Mactra chinensis to salinity, the treatments of salinity gradients and salinity gradual changes were set in this study, and the post growth and development of juveniles were analyzed in recovery experiment, respectively. The result showed that the optimum hatching of zygotes was found at a salinity from 24 to 32, which is narrower than that of larvae (20–32); a slight of low salinity (16–32) will benefit the early growth and development of M. chinensis; at planktonic and creeping stages, low salinity stress (20) was conducive to promoting the growth of juvenile M. chinensis philippi; 4, 48 was the ultimate salinity of M. chinensis; The range of early tolerance of larvae M. chinensis philippi to salinity can be widened through a short period of salinity acclimation. 相似文献
989.
Ardisia violacea (Myrsinaceae), one of China’s rare and endangered species, occurs only in Zhejiang and Taiwan provinces. We examined the population dynamics of this species to reveal details related to the development of populations. Assembling intensity indices were used, such as V/m, K, m*, PAI, CA and I. Age class structure and the time-specific life tables were analyzed by the contiguous grid quadrate method. The population structures and distribution patterns of A. violacea in different habitats, age classes and quadrat scales are discussed and the life parameters such as the survival curve, mortality curve and life expectancy were estimated. The results show the age class distribution of the entire population generally fits a reverse “J” type curve, suggesting a growing population. The population spatial distribution pattern was clumped in all three habitats, especially in the age classes I–III, and had a uniform distribution in the age classes VII and IX. The plants mainly occurred at microsites with generally adequate light, water, nutrients and air. Micro-environmental factors and human factors can also have a great impact. In the age class structure pattern, the individual percentage of the first three age classes accounted for 71.19% in H1 (habitat 1), 68.18% in H2 (habitat 2) and 88.24% in H3 (habitat 3), which indicated the number of individuals in the first three age classes were larger than any other age classes. The population size peaked in the age classes III and X and only 13.1% individuals survive age class III to enter class IV. As a result, fewer middle and advanced aged individuals were found. Age class IV had the highest life expectancy for A. violacea. The survival curve approached to Deevy-II. The spatial distribution pattern of A. violacea populations was decided mainly by the interaction of biological and ecological characteristics of its environment, habitat heterogeneities, microenvironments and human disturbance. 相似文献
990.
Xue-Qin Ma Cheng-Jian Zheng Yan Zhang Chang-Ling Hu Bing Lin Xue-Yan Fu Li-Ya Han Li-Sheng Xu Khalid Rahman Lu-Ping Qin 《Phytochemistry letters》2013,6(1):118-122
A novel bi-isoflavonoid, podocarnone (1), together with five known flavonoids, namely genistein (2), afzelin (3), astragalin (4), luteolin (5) and pratensein (6), were isolated from the whole plants of Podocarpium podocarpum (DC.) Yang and Huang for the first time. The structure of podocarnone (1) was elucidated by detailed spectroscopic analyses, including 1D and 2D NMR techniques. All the isolated compounds were evaluated for their proliferative effects on osteoblasts derived from neonatal rat calvaria and inhibitory effects on multinucleated osteoclasts from rat marrow cells so as to explore the antiosteoporotic activity of these components. Podocarnone (1) exhibited potent stimulatory effects on osteoblastic proliferation and ALP (alkaline phosphatase) activity, and significantly inhibited the activity of osteoclastic TRAP (tartrate-resistant acid phosphatase) in the low concentration range of 10?12–10?14 mol/L, which were equivalent to the activity of genistein (2) in the concentration range of 10?7–10?9 mol/L. The other five known flavonoids also showed varied degrees of antiosteoporotic activities, and structure–activity relationship analysis revealed the number of phenolic rings contained in these structures maybe responsible for the antiosteoporosis property. 相似文献