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941.
Chronic infection with hepatitis B virus (HBV) is associated with the majority of cases of hepatocellular carcinoma (HCC) in China. Despite this, there is no effective method for the early detection of HBV-induced liver cancer. Aberrant fucosylation is known to occur during the development of HCC. We, therefore, developed a method of applying matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze the relationship between aberrant fucosylation, tumor genesis and progression of HBV-associated HCC, and to establish proteomic profiling of serum for early diagnosis of HCC. The MALDI-TOF MS was based on Lens culinaris agglutinin (LCA) lectin magnetic beads and their affinity for separation. The method was applied initially to a 'training' cohort of 111 serum samples obtained from subjects in China with no liver disease (n=26), chronic hepatitis B without cirrhosis (n=21), HBV-infected cirrhosis (n=32), or HBV-infected HCC (n=32). In contrast to previous findings, the results of our profiling analysis demonstrated defucosylation on some of the glycoproteins involved in HCC. HCC was then diagnostically classified in a 'blind test' cohort (n=96). In this group we demonstrated that, HCC could be distinguished from all serum samples, HBV-associated chronic liver disease, and HBV-associated cirrhosis with a sensitivity/specificity of 70%/70%, 78%/74%, and 81%/82%, respectively. When combined with serum alpha-fetoprotein detection (AFP>20 ng/mL), the sensitivity/specificity improved to 78%/88%, 85%/88%, and 89%/91%, respectively. In conclusion, serum glycoprotein fucosylation abnormalities have diverse forms in patients with HCC. MALDI-TOF MS profiling of aberrant serum fucosylated glycoproteins distinguished HCC from controls with high accuracy.  相似文献   
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944.
F Zhu  XH Ma  C Qin  L Tao  X Liu  Z Shi  CL Zhang  CY Tan  YZ Chen  YY Jiang 《PloS one》2012,7(7):e39782
Due to extensive bioprospecting efforts of the past and technology factors, there have been questions about drug discovery prospect from untapped species. We analyzed recent trends of approved drugs derived from previously untapped species, which show no sign of untapped drug-productive species being near extinction and suggest high probability of deriving new drugs from new species in existing drug-productive species families and clusters. Case histories of recently approved drugs reveal useful strategies for deriving new drugs from the scaffolds and pharmacophores of the natural product leads of these untapped species. New technologies such as cryptic gene-cluster exploration may generate novel natural products with highly anticipated potential impact on drug discovery.  相似文献   
945.
The global insight into the relationships between miRNAs and their regulatory influences remains poorly understood. And most of complex diseases may be attributed to certain local areas of pathway (subpathway) instead of the entire pathway. Here, we reviewed the studies on miRNA regulations to pathways and constructed a bipartite miRNAs and subpathways network for systematic analyzing the miRNA regulatory influences to subpathways. We found that a small fraction of miRNAs were global regulators, environmental information processing pathways were preferentially regulated by miRNAs, and miRNAs had synergistic effect on regulating group of subpathways with similar function. Integrating the disease states of miRNAs, we also found that disease miRNAs regulated more subpathways than nondisease miRNAs, and for all miRNAs, the number of regulated subpathways was not in proportion to the number of the related diseases. Therefore, the study not only provided a global view on the relationships among disease, miRNA and subpathway, but also uncovered the function aspects of miRNA regulations and potential pathogenesis of complex diseases. A web server to query, visualize and download for all the data can be freely accessed at http://bioinfo.hrbmu.edu.cn/miR2Subpath.  相似文献   
946.
Zhong  Zhe  Chen  Weijie  Gao  Huan  Che  Ningning  Xu  Min  Yang  Lanqing  Zhang  Yingfang  Ye  Min 《Neurochemical research》2021,46(11):3050-3058
Neurochemical Research - Gut microbiota is closely related to the Parkinson’s disease (PD) pathogenesis. Additionally, aggregation of α-synuclein (α-syn) is central to PD...  相似文献   
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948.
Zhang  M.  Zhang  J.  Jiao  R. T.  Yang  X. E.  Ji  D. W. 《Russian Journal of Plant Physiology》2021,68(6):1115-1124
Russian Journal of Plant Physiology - Hyperaccumulating ecotype (HE) of Sedum alfredii Hance is a Zn/Cd hyperaccumulator, which can accumulate Zn in shoot up to 2% of dry weight, understanding the...  相似文献   
949.
郑雅楠  时勇  李洋  范立淳  王珏  王伟韬 《昆虫学报》2021,64(12):1478-1482
[目的]近年来,松材线虫病扩散到我国的中温带地区,云杉花墨天牛Monochamus saltuarius成为该地区松材线虫的新媒介昆虫.由于中温带地区松材线虫危害松树种类较多,本研究对云杉花墨天牛成虫对4种寄主松树的取食偏好性进行测定,为明确云杉花墨天牛成虫补充营养特性,进而为中温带地区松材线虫病和云杉花墨天牛监测与防...  相似文献   
950.
猪肥胖基因cDNA的克隆与分析   总被引:33,自引:0,他引:33  
戴茹娟  李宁  吴常信 《遗传学报》2000,27(4):290-297
肥胖基因(ab)是近年刚被克隆的新基因,该基因产物Leptin是反映体内脂肪含量和调节体重的重信号因子,首次报道猪ob基因全长序列,并对不同种物ob基因的同源性进行了比较,以λUni-ZAP^TM为载体构建了猪脂肪cDNA文库,根据已知的人和鼠ob基因序列设计PCR引物,利用PCR法筛选猪脂肪cDNA文库,并用RT-PCR从脂肪RNA中扩增的366bp猪ob基因片段作探针,获得了全长3277bp的  相似文献   
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