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Yongye Huang Hongsheng Ouyang Wanhua Xie Xianju Chen Chaogang Yao Yang Han Xiaolei Han Qi Song Daxin Pang Xiaochun Tang 《Cellular signalling》2013,25(4):778-785
Parthenogenetic embryos are invariably lost in mid-gestation, possibly due to the lack of the paternal genome and the consequent induction of aberrant gene expression. Wnt signaling is essential for embryonic development; however, the studies of this pathway in porcine parthenogenetic embryos have been limited. Here, the role of Wnt signaling in porcine parthenogenetic embryos was studied. In vivo embryos were used as controls. Single cell quantitative real-time PCR showed that Wnt signaling was down-regulated in porcine parthenogenetic embryos. Furthermore, immunofluorescence staining and real-time PCR demonstrated that porcine parthenogenetic embryo development was largely unaffected by the inhibition of Wnt signaling with IWP-2, but blastocyst hatching and trophectoderm development was blocked. In addition, parthenogenetic blastocyst hatching was improved by the activation of Wnt signaling by BIO. However, the developmental competency of porcine embryos, including blastocyst hatching, was impaired and apoptosis was induced upon the excessive activation of Wnt signaling. These findings constitute novel evidence that Wnt signaling is important for porcine pre-implantation development and that its down-regulation may lead to the low hatching rate of porcine parthenogenetic blastocysts. 相似文献
74.
Several chiral ligands containing (R,R)‐diaminocyclohexane moieties and pyrrole, furan, or benzene have been synthesized. These ligands were tested in enantioselective zinc‐catalyzed hydrosilylation reactions; excellent enantioselectivities were obtained when the ligands containing (R,R)‐diaminocyclohexane moieties and furan rings were used. For comparison, zinc chloride combined with different potassium carboxylate salts and ligands were also tested for catalytic hydrosilylation reactions. Chirality 25:275–280, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
75.
Alessandra Handisurya Patricia M. Day Cynthia D. Thompson Christopher B. Buck Yuk-Ying S. Pang Douglas R. Lowy John T. Schiller 《Journal of virology》2013,87(24):13214-13225
Full-length genomic DNA of the recently identified laboratory mouse papillomavirus 1 (MusPV1) was synthesized in vitro and was used to establish and characterize a mouse model of papillomavirus pathobiology. MusPV1 DNA, whether naked or encapsidated by MusPV1 or human papillomavirus 16 (HPV 16) capsids, efficiently induced the outgrowth of papillomas as early as 3 weeks after application to abraded skin on the muzzles and tails of athymic NCr nude mice. High concentrations of virions were extracted from homogenized papillomatous tissues and were serially passaged for >10 generations. Neutralization by L1 antisera confirmed that infectious transmission was capsid mediated. Unexpectedly, the skin of the murine back was much less susceptible to virion-induced papillomas than the muzzle or tail. Although reporter pseudovirions readily transduced the skin of the back, infection with native MusPV1 resulted in less viral genome amplification and gene expression on the back, including reduced expression of the L1 protein and very low expression of the L2 protein, results that imply skin region-specific control of postentry aspects of the viral life cycle. Unexpectedly, L1 protein on the back was predominantly cytoplasmic, while on the tail the abundant L1 was cytoplasmic in the lower epithelial layers and nuclear in the upper layers. Nuclear localization of L1 occurred only in cells that coexpressed the minor capsid protein, L2. The pattern of L1 protein staining in the infected epithelium suggests that L1 expression occurs earlier in the MusPV1 life cycle than in the life cycle of high-risk HPV and that virion assembly is regulated by a previously undescribed mechanism. 相似文献
76.
Conrad E. Chan Bryan Z. Zhao Amaury Cazenave-Gassiot Shyue-Wei Pang Anne K. Bendt Markus R. Wenk Paul A. MacAry Brendon J. Hanson 《Journal of lipid research》2013,54(10):2924-2932
Tuberculosis is a major cause of mortality and morbidity due to infectious disease. However, current clinical diagnostic methodologies such as PCR, sputum culture, or smear microscopy are not ideal. Antibody-based assays are a suitable alternative but require specific antibodies against a suitable biomarker. Mycolic acid, which has been found in patient sputum samples and comprises a large portion of the mycobacterial cell wall, is an ideal target. However, generating anti-lipid antibodies using traditional hybridoma methodologies is challenging and has limited the exploitation of this lipid as a diagnostic marker. We describe here the isolation and characterization of four anti-mycolic acid antibodies from a nonimmune antibody phage display library that can detect mycolic acids down to a limit of 4.5ng. All antibodies were specific for the methoxy subclass of mycolic acid with weak binding for α mycolic acid and did not show any binding to closely related lipids or other Mycobacterium tuberculosis (Mtb) derived lipids. We also determined the clinical utility of these antibodies based on their limit of detection for mycobacteria colony forming units (CFU). In combination with an optimized alkaline hydrolysis method for rapid lipid extraction, these antibodies can detect 105 CFU of Mycobacterium bovis BCG, a close relative of Mtb and therefore represent a novel approach for the development of diagnostic assays for lipid biomarkers. 相似文献
77.
Bao-Le Zhang En Zhang Lu-Ping Pang Li-Xing Song Ya-Fei Li Bin Yu Hong-Min Liu 《Steroids》2013,78(12-13):1200-1208
Using dehydroepiandrosterone as the starting material, we have synthesized a series of steroid analogs possessing a D-ring fused with heterocycles which are pyridine, imidazo [2,1-b]thiazoles or substituted thiazole imines. All the final structures are first reported and identified by NMR and MS spectroscopys, the yields of these products are moderate to good and the reaction conditions are mild. The cytotoxicity of the synthesized compounds against EC-109(human esophageal carcinoma), EC-9706(human esophageal carcinoma), MGC-803(human gastric carcinoma) were investigated. 相似文献
78.
Liping Zhang Daiming Jiang Jianlei Pang Rong Chen Xianghong Wang Daichang Yang 《Plant molecular biology》2013,83(1-2):153-161
The high accumulation of a recombinant protein in rice endosperm causes endoplasmic reticulum (ER) stress and in turn dramatically affects endogenous storage protein expression, protein body morphology and seed phenotype. To elucidate the molecular mechanisms underlying these changes in transgenic rice seeds, we analyzed the expression profiles of endogenous storage proteins, ER stress-related and programmed cell death (PCD)-related genes in transgenic lines with different levels of Oryza sativa recombinant alpha antitrypsin (OsrAAT) expression. The results indicated that OsrAAT expression induced the ER stress and that the strength of the ER stress was dependent on OsrAAT expression levels. It in turn induced upregulation of the expression of the ER stress response genes and downregulation of the expression of the endogenous storage protein genes in rice endosperm. Further experiments showed that the ER stress response upregulated the expression of PCD-related genes to disturb the rice endosperm development and induced pre-mature PCD. As consequence, it resulted in decrease of grain weight and size. The mechanisms for the detriment seed phenotype in transgenic lines with high accumulation of the recombinant protein were elucidated. 相似文献
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目的研究G蛋白偶联受体(G protein-coupled receptors)激酶5(GPCR kinase-5,GRK5)基因缺陷和老化交互作用对阿尔茨海默病(Alzheimer's disease,AD)早期的病理改变-海马内肿胀轴突丛(swollen axonal clusters,SACs)出现和积累的影响。方法选取5、6、7、9、12~13、18—19月龄雌性GRK5基因敲除小鼠(GRK5 Knockout,GRK5KO)作为观察对象,另选取年龄匹配的雌性野生型(wild type,WT)小鼠为对照,每个年龄段GRK5KO和WT小鼠各4只。用抗人神经原纤维缠结(neurofibrillary tangles,NFTs)特异性抗体的免疫荧光染色方法观察海马内SACs的变化。结果所有小鼠随着年龄增长,海马内SACs逐渐增加;GRKSKO小鼠组海马内NFT^+ SACs数量较WT型小鼠组显著增加(P〈0.01);双因素方差分析显示遗传性GRK5基因缺陷和老化双因素对海马内NFT^+SACs的影响有显著协同效应(P〈0.01)。结论在促进早期AD病理发生的过程中,GRK5缺陷和老化双因素共同加剧了雌性GRKSKO小鼠海马内SACs的形成与积累。 相似文献