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581.
Sequence variants in the first intron of FTO are strongly associated with human obesity and human carriers of the risk alleles show evidence for increased appetite and food intake. Mice globally lacking Fto display a complex phenotype characterised by both increased energy expenditure and increased food intake. The site of action of FTO on energy balance is unclear. Fasting reduces levels of Fto mRNA in the arcuate nucleus (ARC) of the hypothalamus, a site where Fto expression is particularly high. In this study, we have extended this nutritional link by demonstrating that consumption of a high fat diet (45%) results in a 2.5 fold increase in Arc Fto expression. We have further explored the role of hypothalamic Fto in the control of food intake by using stereotactic injections coupled with AAV technology to bi-directionally modulate Fto expression. An over expression of Fto protein by 2.5-fold in the ARC results in a 14% decrease in average daily food intake in the first week. In contrast, knocking down Arc Fto expression by 40% increases food intake by 16%. mRNA levels of Agrp, Pomc and Npy, ARC-expressed genes classically associated with the control of food intake, were not affected by the manipulation of Fto expression. However, over expression of Fto resulted in a 4-fold increase in the mRNA levels of Stat3, a signalling molecule critical for leptin receptor signalling, suggesting a possible candidate for the mediation of Fto''s actions. These data provide further support for the notion that FTO itself can influence key components of energy balance, and is therefore a strong candidate for the mediation of the robust association between FTO intronic variants and adiposity. Importantly, this provide the first indication that selective alteration of FTO levels in the hypothalamus can influence food intake, a finding consistent with the reported effects of FTO alleles on appetite and food intake in man.  相似文献   
582.
A diarylheptanoid, 1,7-di-(3',4'-dihydroxyphenyl)-4-hepten-3-one, hirsutanone, has been isolated from the methanolic extract of the aerial parts of Viscum cruciatum (Viscaceae) and characterized by spectroscopic methods and chemical transformations. This compound showed cytotoxic activity against melanoma (UACC-62), renal (TK-10) and breast (MCF-7) cancer cell lines.  相似文献   
583.
Viral vectors have a great potential for gene delivery, but manufacturing is a big challenge for the industry. The baculovirus-insect cell is one of the most scalable platforms to produce recombinant adeno-associated virus (rAAV) vectors. The standard procedure to generate recombinant baculovirus is based on Tn7 transposition which is time-consuming and suffers technical constraints. Moreover, baculoviral sequences adjacent to the AAV ITRs are preferentially encapsidated into the rAAV vector particles. This observation raises concerns about safety due to the presence of bacterial and antibiotic resistance coding sequences with a Tn7-mediated system for the construction of baculoviruses reagents. Here, a faster and safer method based on homologous recombination (HR) is investigated. First, the functionality of the inserted cassette and the absence of undesirable genes into HR-derived baculoviral genomes are confirmed. Strikingly, it is found that the exogenous cassette showed increased stability over passages when using the HR system. Finally, both materials generated high rAAV vector genome titers, with the advantage of the HR system being exempted from undesirable bacterial genes which provides an additional level of safety for its manufacturing. Overall, this study highlights the importance of the upstream process and starting biologic materials to generate safer rAAV biotherapeutic products.  相似文献   
584.
Huntington’s disease (HD) is an inherited neurodegenerative disorder characterized by motor, cognitive and behavioral disturbances, caused by the expansion of a CAG trinucleotide repeat in the HD gene. The CAG allele size is the major determinant of age at onset (AO) of motor symptoms, although the remaining variance in AO is highly heritable. The rs7665116 SNP in PPARGC1A, encoding the mitochondrial regulator PGC-1α, has been reported to be a significant modifier of AO in three European HD cohorts, perhaps due to affected cases from Italy. We attempted to replicate these findings in a large collection of (1,727) HD patient DNA samples of European origin. In the entire cohort, rs7665116 showed a significant effect in the dominant model (p value?=?0.008) and the additive model (p value?=?0.009). However, when examined by origin, cases of Southern European origin had an increased rs7665116 minor allele frequency (MAF), consistent with this being an ancestry-tagging SNP. The Southern European cases, despite similar mean CAG allele size, had a significantly older mean AO (p?<?0.001), suggesting population-dependent phenotype stratification. When the generalized estimating equations models were adjusted for ancestry, the effect of the rs7665116 genotype on AO decreased dramatically. Our results do not support rs7665116 as a modifier of AO of motor symptoms, as we found evidence for a dramatic effect of phenotypic (AO) and genotypic (MAF) stratification among European cohorts that was not considered in previously reported association studies. A significantly older AO in Southern Europe may reflect population differences in genetic or environmental factors that warrant further investigation.  相似文献   
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目的:探讨子宫内膜癌患者血浆溶血磷脂酸(LPA)、血清癌抗原125(CA125)及人附睾蛋白4(HE4)的表达及与临床病理特征的关系。方法:选取2014年3月到2016年6月在同济大学附属第一妇婴保健院进行治疗的子宫内膜癌患者76例作为观察组,另选取我院同期收治的子宫内膜增生症患者50例作为良性病变组,再选取同期在我院体检结果为健康的志愿者50例作为对照组。比较三组受试者血浆LPA、血清CA125以及HE4水平。以病理检测结果为金标准,计算血浆LPA、血清CA125、HE4诊断子宫内膜癌的灵敏度、特异度、阳性预测值、阴性预测值。分析子宫内膜癌患者血浆LPA、血清CA125以及HE4水平与临床病理特征的关系。结果:观察组的血浆LPA、血清CA125以及HE4水平均高于对照组和良性病变组(P0.05),良性病变组的血浆中CA125水平高于对照组(P0.05)。血浆LPA、血清CA125以及HE4诊断子宫内膜癌的灵敏度、特异度、阳性预测值、阴性预测值比较无统计学差异(P0.05)。子宫内膜癌患者LPA水平与年龄、肿瘤直径无关(P0.05),与淋巴结转移、临床分期、分化程度、疾病类型有关(P0.05);CA125、HE4水平与年龄、疾病类型无关(P0.05),与淋巴结转移、临床分期、肿瘤直径、分化程度有关(P0.05)。结论:子宫内膜癌患者血浆LPA、血清CA125以及HE4水平偏高,LPA、CA125、HE4与部分临床病理参数相关,三指标对子宫内膜癌均有较高的诊断价值。  相似文献   
589.
四川梅花鹿的行为谱及PAE编码系统   总被引:2,自引:0,他引:2  
2007年3-11月每月定期5 d,每天06:00-18:00在四川省铁布自然保护区的冻列乡、崇尔乡、热尔乡观察记录四川梅花鹿行为发生过程、内容、结果及其周围生境.建立了四川梅花鹿的行为谱、警戒行为谱及其PAE编码系统,填补了有蹄类警戒行为PAE编码的空白.分辨并记录了四川梅花鹿的11种姿势、83种动作及136种行为,描述了各种行为的相对发生频次与性别、年龄、季节的关系.与其他有蹄类相比,梅花鹿的行为与鹿科其他动物有相似之处.  相似文献   
590.
自林奈建立杨属(Populus)以来,众多的学者对杨属的分类进行了研究,并建立了较多的分类系统。目前的国际杨属分类,总体上还停留在传统形态分类阶段,存在明显的地域和国别特征。尽管各国在主流上都采用“属—组—种”的分类阶元,但在种、亚种、变种的划分上,却存在很大的不同。中国和美国分别是细分派和聚合派的代表,两国的分类系统存在很大分歧,但各有优点和缺点。即使在国内,杨属分类也还有很多需要解决的问题。新兴的分子系统学研究,为杨属的分类修订提供了一些有益参考,但总体贡献不大。国际杨属分类的趋势和终极目标是建立基于系统发生的统一分类系统。这需要基于种群和综合物种概念,融合形态学、生态学、生物地理学、基因组生物信息学和进化生物学等的综合系统分类来实现。  相似文献   
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