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941.
The relationship of four potentially functional polymorphisms of the vitamin D receptor (VDR) gene, ApaI, BsmI, FokI and TaqI , with tuberculosis susceptibility were considered. The aim of this meta-analysis was to explore the association between the four polymorphisms and tuberculosis risk in different ethnic backgrounds. Eligible case-control studies that were catalogued before April 1st 2013 were enrolled, and the heterogeneity between the studies was evaluated using a χ2 based Q-test. Fixed and random effect models were built to evaluate the association of the four polymorphisms with the risk of tuberculosis, and the association between the four polymorphisms and tuberculosis was expressed as the odds ratio (OR) and 95% confidence interval (CI). Finally, twenty nine qualified studies were enrolled for this meta-analysis that included 6179 tuberculosis cases and 6585 healthy controls. The variant homozygote genotype of the FokI polymorphism was associated with a significantly increased risk of tuberculosis when compared to the heterozygote and wild type homozygote genotypes in the Chinese population (ff vs. Ff+FF: ORrecessive=1.97, 95%CI: 1.32-2.93, P
bonferroni=0.0032; heterogeneity test: χ2=0.24, P=0.62). For European subjects, the homozygote and heterozygote genotypes of the BsmI polymorphism were associated with a significantly decreased risk of tuberculosis when compared to the wild type homozygote (bb+Bb vs. BB: ORdominant=0.41, 95%CI, 0.22-0.76, P
bonferroni=0.02; heterogeneity test: χ2=2.59, P=0.11). Based on the above results, we conclude that variants of the VDR gene that are homozygous for the FokI polymorphism might be more susceptible to tuberculosis in Chinese. Furthermore, larger sample studies are warranted to confirm the protective effects of BsmI variants on tuberculosis in the Europeans. 相似文献
942.
943.
目的:探讨自杀未遂老年抑郁症患者血清5-羟色胺(5-HT)水平、总胆固醇(TC)、C反应蛋白(CRP)及白介素-6(IL-6)检测的临床意义。方法:选取2015年5月至2018年5月我院收治的首次住院的老年抑郁症患者155例,依据入院前2周内是否曾有过自杀行为将其分为自杀未遂组(n=75)和无自杀行为组(n=80)。比较两组患者的临床指标及血清5-HT、TC、CRP及IL-6水平;分析不同病情严重程度自杀未遂老年抑郁症患者血清5-HT、TC、CRP及IL-6水平;采用Pearson相关分析血清5-HT、TC、CRP及IL-6水平与汉密尔顿抑郁量表(HAMD)评分的相关性。结果:自杀未遂组HAMD评分高于无自杀行为组(P<0.05)。自杀未遂组血清5-HT及TC水平均低于无自杀行为组(P<0.05),自杀未遂组血清CRP及IL-6水平均高于无自杀行为组(P<0.05)。与轻度组比较,中度组、重度组患者血清5-HT及TC水平均明显降低,且重度组低于中度组(P<0.05);与轻度组比较,中度组和重度组患者血清CRP及IL-6水平均明显升高,且重度组高于中度组(P<0.05)。5-HT、TC与HAMD评分呈负相关(P<0.05);CRP、IL-6与HAMD评分呈正相关(P<0.05)。结论:自杀未遂老年抑郁症患者血清5-HT、TC水平降低,CRP、IL-6水平升高,检测血清5-HT、TC、CRP及IL-6有助于评价其病情严重程度及出现自杀行为的风险。 相似文献
944.
945.
Yang Bai Miao Li Yanmei Zhou Lei Ma Qian Qiao Wanling Hu Wei Li Zachary Patrick Wills Wen-Biao Gan 《Molecular neurodegeneration》2017,12(1):86
Background
Alzheimer’s disease (AD) is characterized by amyloid deposition, tangle formation as well as synapse loss. Synaptic abnormalities occur early in the pathogenesis of AD. Identifying early synaptic abnormalities and their underlying mechanisms is likely important for the prevention and treatment of AD.Methods
We performed in vivo two-photon calcium imaging to examine the activities of somas, dendrites and dendritic spines of layer 2/3 pyramidal neurons in the primary motor cortex in the APPswe/PS1dE9 mouse model of AD and age-matched wild type control mice. We also performed calcium imaging to determine the effect of Aβ oligomers on dendritic calcium activity. In addition, structural and functional two-photon imaging were used to examine the link between abnormal dendritic calcium activity and changes in dendritic spine size in the AD mouse model.Results
We found that somatic calcium activities of layer 2/3 neurons were significantly lower in the primary motor cortex of 3-month-old APPswe/PS1dE9 mice than in wild type mice during quiet resting, but not during running on a treadmill. Notably, a significantly larger fraction of apical dendrites of layer 2/3 pyramidal neurons showed calcium transients with abnormally long duration and high peak amplitudes during treadmill running in AD mice. Administration of Aβ oligomers into the brain of wild type mice also induced abnormal dendritic calcium transients during running. Furthermore, we found that the activity and size of dendritic spines were significantly reduced on dendritic branches with abnormally prolonged dendritic calcium transients in AD mice.Conclusion
Our findings show that abnormal dendritic calcium transients and synaptic depotentiation occur before amyloid plaque formation in the motor cortex of the APPswe/PS1dE9 mouse model of AD. Dendritic calcium transients with abnormally long durations and high amplitudes could be induced by soluble Aβ oligomers and contribute to synaptic deficits in the early pathogenesis of AD.946.
本文记述中国二叉蚜属SchizaphisBruer6种,其中包括3新种:贴梗海棠二叉蚜Schizaphis(Schizaphis)chaenometicolaZhang,sp.nov.香草二叉蚜Schizaphis(Schizaphis)hierochlophagaZhangetChen,sp.nov.和长管二叉蚜Schizophis(Schizaphis)longituberclataZhangetQiao,sp.nov,并附亚属、种检索表。模式标本存放中国科学院动物研究所标本馆。贴梗海棠二叉蚜Schizapais(Schizaphis)chaenometicolaZhang,新种(图1)正模:无翅孤雌蚜,No.8101-1-11,甘肃:天水(北纬34.6°,东经105.7°)1580m,贴梗海棠Chaenomelesspeciosa(Sweet),1985-VII-7,23,张广学、钟铁森;副模:7无翅孤雌蚜,其它同上。该种触角约为体长的0.50~0.70倍,腹管略长于尾片,与香草二叉蚜相近,但腹部各节无缘瘤,中胸腹盆两臂分离,寄主贴梗海棠和山丁子,使其不同于本属内任何种。香草二叉蚜Schizaphis(Schizaphis)hierochlophagaZhangetChen,新种(图2)正模:有翅孤雌蚜,No.Y2690-1-1-3,北京(北纬39.3°,东经116.4°)100m,香茅草Cymbopogonspp,1983-VI-2,张向才。副模:1有翅孤雌蚜,1无翅孤雌蚜,No.Y2690-11-2,其它同上。该种触角约为体长的0.64倍,有翅孤雌蚜触角3~5 相似文献
947.
本研究旨在建立对肠道主要共生菌的快速定量方法。根据细菌16S rRNA基因的保守序列并参考相关研究,设计针对总肠道菌群的通用引物和探针,以及针对双歧杆菌属、肠球菌属和肠杆菌科的特异性引物和探针,采用引物设计工具(Primer-BLAST) 以及聚合酶链式反应(polymerase chain reaction, PCR)扩增以验证引物和探针的特异性。通过分子克隆技术,构建各目标菌属目的基因的重组质粒作为qPCR检测的标准模板,选择标准模板进行重复性实验,并计算组内和组间重复变异系数。用所建立的方法对不同年龄段的临床粪便标本进行3类细菌的检测,并初步分析这些菌群与增龄的关系。结果显示,引物和探针具有较高的特异性;各目的细菌标准曲线在一定范围内线性关系良好,总菌群或各目标菌属的线性范围分别为:总菌群2.9×103~2.9×1012copies/μL、双歧杆菌3.1×102~3.1×109 copies/μL、肠球菌5.9×102~5.9×109 copies/μL、肠杆菌6.3×102~6.3×109 copies/μL,决定系数R2≥ 0.995;检测的最低拷贝数为总菌群7.5×102 copies/μL、双歧杆菌 46 copies/μL、肠球菌 37 copies/μL、肠杆菌 51 copies/μL;重复性实验变异系数在1.32%以下,具有良好的可重复性。对不同年龄段临床粪便标本检测的结果显示,肠球菌和肠杆菌含量随增龄呈增长趋势,且老年组含量显著高于青年组,但在高龄老年人中未发现肠球菌数量增加。双歧杆菌含量随增龄减少,且各组间差异显著,在高龄老年人中也未观察到双歧杆菌显著减少。结果提示,本研究建立了一种可供临床推广的菌群绝对定量方法,能够同时检测3类细菌和菌群总量,对于菌群定量研究具有实际意义。 相似文献
948.
溶血磷脂酸促进离体大鼠胚胎神经干细胞的增殖及其向胆碱能神经元分化 总被引:3,自引:0,他引:3
溶血磷脂酸(1ysophosphatidic acid,LPA)是一种细胞外磷脂信号。本研究用[^3H]-胸腺嘧啶掺入法、免疫细胞化学和Western blot等技术,观察了LPA对体外培养的大鼠胚胎神经干细胞(neural stem cells,NSCs)的增殖以及向MAF2标记的一般神经元和ChAT标记的胆碱能神经元的分化的影响。结果显示:(1)在特殊的无血清培养基中加入低浓度的LPA(0.01-1.0μmol/L)后,NSCs对【^3H】-胸腺嘧啶的摄入呈剂量依赖性增加,表明LPA对NSCs有显著的促增殖作用;(2)在培养基中加入胎牛血清以诱导NSCs的分化,发现低浓度的LPA增加MAF2阳性和ChAT阳性神经元的比例,0.1μmol/L LPA引起的增加达到峰值;(3)Western blot分析显示LPA促进了MAP2和ChAT的表达;(4)在诱导NSCs出现分化早期,用倒置显微镜观察到低浓度的LPA明显促进细胞突起的生长和细胞的迁移。以上结果表明,低浓度LPA在一定范围内可以促进NSCs的增殖、并分化为一般的MAP2阳性神经元和特殊的胆碱能神经元,而且LPA可以促进在分化早期出现的神经元或神经胶质细胞前体细胞的迁移和突起生长。 相似文献
949.
Yong-Ping Zhang Fei-Fei Jia Xiao-Mei Zhang Yong-Xu Qiao Kai Shi Yan-Hong Zhou Jing-Quan Yu 《Acta Physiologiae Plantarum》2012,34(2):713-720
Suboptimal root zone temperature (14°C) was imposed on chilling-sensitive cucumber (Cucumis sativus L.) and chilling-tolerant figleaf gourd (Cucurbita ficifolia Bouché) plants. Exposure of roots to low temperature for up to 10 days caused a strong growth inhibition in cucumber compared
with figleaf gourd. Physiological analysis showed that generation of reactive oxygen species (ROS) such as hydrogen peroxide
and superoxide anion was significantly induced in cucumber plants as fast as 1 day after low root zone temperature treatment.
In addition to the significant induction of antioxidant superoxide dismutase activity, low root zone temperature also increased
the mitochondrial electron transport allocated to alternative pathway while decreased cytochrome pathway salicylhydroxamic
acid-resistant respiration. However, these defense responses could not compensate for the ROS production, resulting in membrane
lipid peroxidation and loss of root cell viability in the low root zone temperature treated cucumber roots. In contrast, 14°C
root zone temperature had no significant effects on figleaf gourd plant growth, antioxidant enzymes, ROS levels and alternative
respiratory pathway. Hence, difference in ROS metabolism would be associated with the remarkable difference in adaptability
of cucumber and figleaf gourd plants in response to suboptimal root zone temperature condition. 相似文献
950.