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81.
Copy-Number Mutations on Chromosome 17q24.2-q24.3 in Congenital Generalized Hypertrichosis Terminalis with or without Gingival Hyperplasia 总被引:1,自引:0,他引:1
Miao Sun Ning Li Wu Dong Qing Liu Guang He Xin Li Yang Luo Dan Lv Dai Zhang Chaoxia Lu Lihua Cao W.H. Irwin McLean Ming-Rong Wang Lin He Wilson H.Y. Lo 《American journal of human genetics》2009,84(6):807-813
Congenital generalized hypertrichosis terminalis (CGHT) is a rare condition characterized by universal excessive growth of pigmented terminal hairs and often accompanied with gingival hyperplasia. In the present study, we describe three Han Chinese families with autosomal-dominant CGHT and a sporadic case with extreme CGHT and gingival hyperplasia. We first did a genome-wide linkage scan in a large four-generation family. Our parametric multipoint linkage analysis revealed a genetic locus for CGHT on chromosome 17q24.2-q24.3. Further two-point linkage and haplotyping with microsatellite markers from the same chromosome region confirmed the genetic mapping and showed in all the families a microdeletion within the critical region that was present in all affected individuals but not in unaffected family members. We then carried out copy-number analysis with the Affymetrix Genome-Wide Human SNP Array 6.0 and detected genomic microdeletions of different sizes and with different breakpoints in the three families. We validated these microdeletions by real-time quantitative PCR and confirmed their perfect cosegregation with the disease phenotype in the three families. In the sporadic case, however, we found a de novo microduplication. Two-color interphase FISH analysis demonstrated that the duplication was inverted. These copy-number variations (CNVs) shared a common genomic region in which CNV is not reported in the public database and was not detected in our 434 unrelated Han Chinese normal controls. Thus, pathogenic copy-number mutations on 17q24.2-q24.3 are responsible for CGHT with or without gingival hyperplasia. Our work identifies CGHT as a genomic disorder. 相似文献
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84.
Cheng-Jun He Cheng Peng Xiao-Fang Xie Li Guo Qin-Mei Zhou Xiao-Hong Li Ou Dai Zhao Geng Yi-Ping Guo 《Phytochemistry letters》2013,6(2):299-301
Two new dianthramide glucosides, N-(2′-β-d-glucopyranosyl-5′-hydroxysalicyl)-4-hydroxy-3-methoxyanthranilic acid methyl ester (1) and N-(2′-β-d-glucopyranosyl-5′-hydroxysalicyl)-4-hydroxyanthranilic acid methyl ester (2), together with five known glycosides, were isolated from the lateral roots of Aconitum carmichaelii. Their structures were elucidated by spectroscopic analyses. In the in vitro assays, compounds 1 and 2 showed activity against pentobarbital sodium-induced cardiomyocytes damage by recovering beating rhythm and increasing the cell viability. 相似文献
85.
High-level cryIVD and cytA gene expression in Bacillus thuringiensis does not require the 20-kilodalton protein, and the coexpressed gene products are synergistic in their toxicity to mosquitoes. 总被引:3,自引:5,他引:3 下载免费PDF全文
Interactions among the 20-kDa protein gene and the cytA and cryIVD genes located in a 9.4-kb HindIII fragment were studied. A series of plasmids containing a combination of these different genes was constructed by using the Escherichia coli/Bacillus thuringiensis shuttle vector pHT3101. The plasmids were then used to transform an acrystalliferous strain, cryB, derived from B. thuringiensis subsp. kurstaki. The results from sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analyses suggest that although the 20-kDa protein is required for the efficient CytA protein production in E. coli, it is not required in B. thuringiensis. With or without the truncated 20-kDa protein gene, the CtyA and/or CryIVD proteins are produced and form parasporal inclusions in B. thuringiensis cells. However, more-efficient expression is obtained when a second protein, probably acting as a chaperonin, is present. In addition, the time course studies show that the CytA and CryIVD proteins are coordinately produced. Both the crude B. thuringiensis culture and purified inclusions from each recombinant B. thuringiensis strain are toxic to Culex quinquefasciatus larvae. The parasporal inclusions formed in B. thuringiensis cells are mosquitocidal, with CytA synergizing CryIVD toxicity. 相似文献
86.
Xie C Yang S Zhong D Dai X Chen X 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(28):3071-3075
Dronedarone is a derivative of amiodarone--a popular antiarrhythmic drug. It was developed to overcome the limiting iodine-associated toxicities of amiodarone. Debutyldronedarone is a major circulating active metabolite of dronedarone in humans. To investigate the pharmacokinetics of dronedarone, a rapid, simple, and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously determine dronedarone and debutyldronedarone in human plasma using amiodarone as internal standard (IS). Acetonitrile with IS was used to precipitate proteins from a 50-μL aliquot of plasma. Effective chromatographic separation was performed on a CAPCELL PAK C(18) MG (100 mm × 4.6 mm, 5 μm) column with gradient elution (5 mmol/L ammonium acetate-acetonitrile, with each phase containing 0.2% acetic acid) at a flow rate of 0.7 mL/min. Complete separation was achieved within 5.5 min. Detection was carried out on an tandem mass spectrometer in multiple reaction monitoring mode using a positive atmospheric pressure chemical ionization interface. A lower limit of quantification of 0.200 ng/mL was achieved for both dronedarone and debutyldronedarone, with acceptable precision and accuracy. The linear range of the method was from 0.200 to 200 ng/mL for each analyte. Intra- and inter-day precisions were lower than 7.2% in relation to relative standard deviation, while accuracy was within ±5.1% in terms of relative error for analytes. Our findings demonstrate the successful application of the validated LC-MS/MS method to a pharmacokinetic study after a single oral administration of 400mg dronedarone to six healthy volunteers. 相似文献
87.
Jian Guo Dacheng Peng Qing Dai Shutsung Liao Brian J. Wright Richard B. van Breemen 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(21):1885-1888
The steroidal liver X receptor agonist, 3α,6α,24-trihydroxy-24,24-di(trifluoromethyl)-5β-cholane (ATI-829) is a potential therapeutic agent for the treatment of atherosclerosis. A sensitive and selective liquid chromatography–tandem mass spectrometry (LC–MS–MS) method for the quantification of ATI-829 in mouse plasma was developed and validated. Proteins in a 25 μL aliquot of mouse plasma were precipitated, and ATI-829 was extracted from the precipitate by the addition of 125 μL methanol. The overall extraction efficiency was greater than 99%. LC–MS–MS with negative ion electrospray and selected reaction monitoring was used for the quantitative analysis of ATI-829. The lower limit of quantitation of ATI-829 corresponded to 5.0 ng/mL (9.7 nM) plasma. Interference from matrix was negligible. The calibration curve was linear over the range 5–2000 ng/mL. The intra-day precision and inter-day precision of the analyses were <4.5% and <6%, respectively, and the accuracy ranged from 92% to 103%. ATI-829 in plasma was stable for at least 6 h at room temperature, 1 week at 4 °C, and 3 weeks at −20 °C. The validated method was then utilized for pharmacokinetic studies of ATI-829 administered to mice. 相似文献
88.
合成基因组学:设计与合成的艺术 总被引:1,自引:0,他引:1
随着基因组相关技术(测序、编辑、合成等)和知识(功能基因组学)的日益成熟,合成基因组学在本世纪迎得了发展的契机。病毒、原核生物的全基因组相继被化学合成并支持生命的存活,第1个真核生物合成基因组计划已经完成过半,人类基因组编写计划提上日程。在基因组合成的实践过程中,研究者们不断探索对基因组进行重编和设计所应遵循的规则,提高从头合成、组装和替换基因组的技术手段。合成基因组在工业、环境、健康和基础研究领域有着广阔的应用前景,同时也带来了相应的伦理问题。结合在Sc2.0计划中的基因组合成研究和近期合成基因组学所取得的重大进展,本文综述了基因组设计和合成相关的科学、技术和伦理内容,并探讨了未来发展所面对的挑战。作为合成生物学最重要的领域之一,合成基因组学方兴未艾。 相似文献
89.
<正> 1983年以来,人们相继从人和大鼠等动物的心房中分离到心房利钠多肽(ANP)。但对非人灵长类动物——恒河猴的ANP了解甚少。由于ANP对机体循环系统的调节起着重要作用,其强大的降压、利钠、利尿的生理功能,在心血管疾病的防治方面具有重要意义。我们曾报导过恒河猴心房肌细胞中存在着大量的ANP样物质,随后对此物质进行了分离、纯化及活性检测,现简报如下。 相似文献
90.
Wenjie Sun Changkai Sun Hui Zhao Hang Lin Qianqian Han Jingyu Wang Hui Ma Bing Chen Zhifeng Xiao Jianwu Dai 《PloS one》2009,4(7)