新疆维吾尔族和汉族亚甲基四氢叶酸还原酶基因多态性研究

目的:研究新疆维吾尔族、汉族两民族亚甲基四氢叶酸还原酶(Methyleneterahyofolate reductase MTHFR)基因多态性的分布情况,获取新疆维吾尔族与汉族MTHFR 1298位群体遗传学数据。方法:应用PCR-RFLP技术检测新疆维吾尔族及汉族MTHFR1298位多态性位点基因频率及基因型频率。结果:新疆维吾尔族、汉族MTHFR 1298位C等位基因分布频率分别为12%、23%,P<0.05有统计学差异性,且新疆维吾尔族MTHFR 1298位C等位基因分布频率与现有报道的少数民族贵州苗族、布依族具有统计学差异。结论:MTHFR 1298位多态性在不同民族具有差异性:MTHFR 1298位多态性在新疆维吾尔族和汉族有民族差异;新疆新疆维吾尔族MTHFR 1298位C等位基因频率与贵州苗族、布依族少数民族之间具有民族差异性。     

MTHFR C677T、A1298C基因多态性与老年单纯收缩期高血压患者Hcy、血脂水平的关系研究

摘要 目的：研究5,10-亚甲基四氢叶酸还原酶（MTHFR）C677T、A1298C基因多态性与老年单纯收缩期高血压（ISH）患者同型半胱氨酸（Hcy）、血脂水平的关系。方法：选取2019年3月至2021年3月期间中南大学湘雅医学院附属海口医院全科医学科收治的212例老年ISH患者作为ISH组,以同期体检无高血压老年人120例为对照组。检测两组MTHFR C677T、A1298C基因多态性。收集两组一般资料及血浆Hcy及血脂检查结果。观察MTHFR C677T、A1298C不同基因型的血浆Hcy、血脂水平差异。采用多因素Logistic回归分析老年ISH发生的影响因素。结果：相比于对照组,ISH组MTHFR C677T位点T等位基因频率较高,C等位基因频率较低;ISH组CC基因型频率较低,CT、TT基因型频率较高（P<0.05）。相比于对照组,ISH组A1298C位点C等位基因频率较高,A等位基因频率较低;ISH组A1298C位点AA基因型频率较低,CC、AC基因型频率较高（P<0.05）。MTHFR基因C677T位点不同基因型血浆Hcy、总胆固醇（TC）水平差异具有显著性（P<0.05）。MTHFR基因A1298C位点不同基因型血浆Hcy、TC水平明显差异具有显著性（P<0.05）。血浆Hcy、MTHFR C677T及A1298C基因多态性是老年ISH发生的影响因素（均P<0.05）。结论：MTHFR C677T、A1298C基因多态性与老年ISH患者血浆TC、Hcy水平有关,血浆Hcy、MTHFR C677T及A1298C基因多态性是老年ISH发生的影响因素。     

MTHFR基因多态性与中国北方人群脑膜瘤发病的相关性分析

目的:探讨亚甲基四氢叶酸还原酶(MTHFR)基因多态性与中国北方人群脑膜瘤发病的相关性。方法:选择2012年1月-2013年12月在黑龙江省哈尔滨医科大学附属第二医院的第一、三病房接受手术治疗的脑膜瘤患者317例(实验组)及320例非脑膜瘤患者(对照组)为研究对象,利用聚合酶链反应限制性多态性片段长度(PCR-RFLP)检测和比较两组MTHFR两个单核苷酸多态性位点(C677T、A1298C)各种基因型(CC、CT、TT)的分布情况及等位基因的频率。结果:两组MTHFR的C677T中CC基因型的频率和TT基因型的频率比较有显著性差异(CC:OR=2.012,95%CI=1.460-2.772;TT:OR=0.399,95%CI=0.254-0.628,P0.05),实验组MTHFR的(0.450)C677T中的T等位基因频率明显高于对照组(0.320)(OR=0.529,95%CI=0.420-0.666,P0.05)。两组A1298C的等位基因分布比较没有统计学差别(P0.05)。结论:MTHFR基因的C677T中TT等位基因提示潜在的易患脑膜瘤的风险,而CC等位基因会降低中国北方人群患脑膜瘤的风险。     

不明原因复发性自然流产夫妇MTHFR C677T位点多态性分析

目的：分析不明原因复发性自然流产（URSA）夫妇与亚甲基四氢叶酸还原酶基因C677T（MTHFR C677T）位点多态性的关 联性研究。方法：采用聚合酶链式反应- 限制性片段长度多态性( PCR-RFLP)对URSA 组和对照组各50 对夫妇的外周血进行 MTHFR C677T 的位点多态性进行检测分析。结果：URSA 组MTHFR 基因677 位点的T/T、C/T+T/T 基因型的发生频率显著高于 对照组,差异具有统计学意义(P<0.05),而对照组MTHFR 基因677 位点的C/C 基因型发生频率显著高于URSA 组（P<0.05）,两 组MTHFR 基因677 位点的C/T 基因型比较无明显差异（P>0.05)。另外URSA 组等位基因T 明显高于C 的频率,且URSA 组等 位基因T 发生频率显著高于对照组,对照组等位基因C 发生频率显著高于USRA 组,差异均具有统计学意义（P<0.05）。结论： MTHFR C677T 位点的多态性与URSA 的发生密切相关,是该病的重要遗传风险因素。     

赤峰市汉族和蒙古族孕期女性MTHFR与MTRR的基因多态性分布研究

针对赤峰市汉族和蒙古族孕期女性开展分子流行病学调查,研究叶酸代谢关键酶5,10-亚甲基四氢叶酸还原酶(5,10-methylenetetrahydrofolate reductase, MTHFR) C677T、A1298C以及甲硫氨酸合成酶还原酶(methionine synthase reductase, MTRR) A66G的基因多态性在该地区汉族及蒙古族中的分布。以孕期保健的853名女性为研究对象,其中汉族647人、蒙古族206人。采集口腔黏膜上皮脱落细胞,抽提基因组DNA,使用荧光定量PCR方法检测MTHFR C677T、A1298C和MTRR A66G的基因多态性,并进行统计学分析。结果显示:1)入组对象的基因多态性分布符合遗传平衡; 2)汉族和蒙古族孕期女性MTHFR C677T位点基因型CC、CT、TT的频率分别为15.61%、52.40%、31.99%与23.79%、50.97%、25.24%,差异具有统计学意义(P0.05)。汉族和蒙古族孕期女性MTHFR A1298C位点基因型AA、AC、CC的频率分别为76.04%、22.10%、1.86%与74.27%、23.30%、2.43%,差异无统计学意义(P0.05)。汉族和蒙古族孕期女性MTRR A66G位点基因型AA、AG、GG的频率分别为58.42%、36.63%、4.95%与50.48%、40.78%、8.74%,差异具有统计学意义(P0.05); 3)汉族和蒙古族孕期女性MTHFR C677T和A1298C两位点连锁有6种组合,频率最高的是CT/AA,之后依次是TT/AA、CT/AC、CC/AA、CC/AC、CC/CC,没有CT/CC、TT/AC和TT/CC组合。两位点间存在完全连锁不平衡。本研究获取的赤峰市汉族、蒙古族孕期女性MTHFR和MTRR基因多态性的群体遗传学特征,为指导科学增补叶酸营养、实施个性化孕期保健提供了依据。     

缺血性脑卒中患者同型半胱氨酸代谢相关酶基因突变的研究

为研究同型半胱氨酸代谢相关酶亚甲基四氢叶酸还原酶(MTHFR)基因C677T和胱硫醚-β-合成酶(CBS)基因T833C位点碱基突变与缺血性脑卒中的关系,对74例缺血性脑卒中患者和83例健康对照者,采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)技术检测MTHFR基因C677T基因型,用扩增阻滞突变体系法(ARMS)检测CBS基因T833C突变。实验检出患者组MTHFR基因T纯合基因型、杂合基因型和T等位基因频率分别为2.7％、51.4％和28.4％,对照组分别为1.2％、39,8％和21.1％。患者组CBS基因C纯合基因型和C等位基因频率分别为13.5％和43.9％,对照组分别为6.0％和38.0％。Multiple Logistic Regression分析显示;C677T位点T等位基因,T833C位点C等位基因以及年龄均与缺血性脑卒中发病有关(P<0.05),C677T位点T等位基因的比值比(OR)为1.74(95％CI 1.06～2,B6)和T833C位点C等位基因的比值比为1.73(95％CI 1.07～-2.81)。实验显示MTHFR C677T和CBS T833C基因位点突变与缺血性脑卒中发病有关,上述两个基因位点突变可能是缺血性脑卒中发病的遗传因素。     

MTHFR及PAI基因多态性与新生儿早产易感性的关系

目的:探讨MTHFR基因、PAI-1基因多态性与新生儿早产的关系。方法:选自2014年1月-2015年1月期间我院住院患儿285例并分为四组。抽取研究对象静脉血进行目的基因MTHFR基因C677T、PAI基因的提取、扩增及检测。结果:MTHFR基因C677T扩增片段198 bp,经限制性内切酶作用后形成野生CC型(片段198 bp)、纯合子突变TT型(175 bp、23 bp)以及杂合子突变CT型(23 bp、175 bp以及198 bp);PAI基因扩增片段142 bp,经限制性内切酶作用后形成三中基因型,分别为4G/4G型(96 b p、46 bp)、5G/5G型(22 bp、46 bp以及74 bp)以及4G/5G型(22 bp、46 bp、74 bp以及96 bp)。早产儿童与足月儿童MTHFR基因67 7位点T等位基因分布差异显著(P0.05),早产儿童与足月儿童PAI基因启动子675位点4G等位基因分布无显著性差异(P0.05)。结论:早产发生的易感性与多方面因素有关,其中遗传因素方面MTHFR基因677位点T等位基因多态性可能与新生儿早产相关,而PAI基因启动子675位点基因的多态性与新生儿早产的发生无显著相关。     

健康人群肿瘤坏死因子-α基因多态性的分析

了解汉族健康人群中TNF-A基因多态性的分布,研究TNF-α表达与相关疾病之间的联系。采用PCR-限制性长度片段多态分析法检测140名重庆地区汉族健康人群的TNF—A-308,TNF—A-857位点基因多态性,计算其基因型和等位基因频率,结果显示TNF-A-308G／G、G／A、4朋基因型的频率分别为89％、11％、1％,其等位基因的发生频率以G等位基因最常见（93％）,其次为A等位基因（7％）。TNF—A-857C／C、C／T、形,基因型的频率分别为68％、36％、8％,其等位基因发生频率以C等位基因最常见（81％）,其次为T等位基因（19％）。由结果可以得出重庆地区汉族健康人群TNF—A-308位点存在G／A多态性,TNF-A-857位点存在C／T多态性。     

亚甲基四氢叶酸还原酶基因C677T、G1793A单核苷酸多态性与散发性乳腺癌易感性的关系

目的：研究亚甲基四氢叶酸还原酶（MTHFR）基因C677T、G1793A位点单核苷酸多态性与散发性乳腺癌易感性关系。方法：采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法,对200例乳腺癌患者及200例正常对照者MTHFR基因C677T、G1793A位点单核苷酸多态性进行分析,logistic回归分析不同基因型与乳腺癌风险的关系。结果：乳腺癌组MTHFR 677TT基因型频率为25.00%显著高于正常对照组的10.50%（X2=14.401,P=0.001）,CT基因型频率为44.50%低于正常对照组的54.50%,CC基因型频率在乳腺癌组和正常对照组中无差别;MTHFR 1793GA基因型频率为18.50%显著高于正常对照者的8.50%（X2=8.563,P=0.003）。乳腺癌患者MTHFR 677T和1793A等位基因频率分别为47.25%、9.25%,显著高于对照组中的37.75%、4.25%。MTHFR 677TT基因型携带者罹患乳腺癌的风险是677CC基因型携带者的2.732倍（95%CI=1.418～5.051,P=0.001）,MTHFR1793GA基因型携带者罹患乳腺癌的风险是1793GG基因型携带者的2.444倍（95%CI=1.325～4.505,P=0.003）。另外,乳腺癌组中MTHFR C677T基因多态性与肿瘤大小相关（x2=7.431,P=0.024,MTHFR G1793A基因多态性与淋巴结转移情况（x2=8.939,P=0.011）、癌组织学分级（x2=9.983,P=0.007）相关。结论：MTHFR C677T、G1793A基因多态性与散发性乳腺癌的易感性相关。     

亚甲基四氢叶酸还原酶基因C677T、G1793A 单核苷酸多态性 与散发性乳腺癌易感性的关系

目的:研究亚甲基四氢叶酸还原酶(MTHFR)基因C677T、G1793A位点单核苷酸多态性与散发性乳腺癌易感性关系。方法:采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法,对200例乳腺癌患者及200例正常对照者MTHFR基因C677T、G1793A位点单核苷酸多态性进行分析,logistic回归分析不同基因型与乳腺癌风险的关系。结果:乳腺癌组MTHFR 677TT基因型频率为25.00%显著高于正常对照组的10.50%(X2=14.401,P=0.001),CT基因型频率为44.50%低于正常对照组的54.50%,CC基因型频率在乳腺癌组和正常对照组中无差别;MTHFR 1793GA基因型频率为18.50%显著高于正常对照者的8.50%(X2=8.563,P=0.003)。乳腺癌患者MTHFR 677T和1793A等位基因频率分别为47.25%、9.25%,显著高于对照组中的37.75%、4.25%。MTHFR 677TT基因型携带者罹患乳腺癌的风险是677CC基因型携带者的2.732倍(95%CI=1.418～5.051,P=0.001),MTHFR1793GA基因型携带者罹患乳腺癌的风险是1793GG基因型携带者的2.444倍(95%CI=1.325～4.505,P=0.003)。另外,乳腺癌组中MTHFR C677T基因多态性与肿瘤大小相关(x2=7.431,P=0.024,MTHFR G1793A基因多态性与淋巴结转移情况(x2=8.939,P=0.011)、癌组织学分级(x2=9.983,P=0.007)相关。结论:MTHFR C677T、G1793A基因多态性与散发性乳腺癌的易感性相关。     

Role for dopamine in malonate-induced damage in vivo in striatum and in vitro in mesencephalic cultures

Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.     

SSTR5 ablation in islet results in alterations in glucose homeostasis in mice

Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义。综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望。     

2018年中国植物科学若干领域重要研究进展

2018年中国植物科学继续呈现快速发展的态势, 我国科学家在国际植物科学主流学术刊物发表论文数量大幅增加, 取得了多项具有重要影响的成果。调控植物生长-代谢平衡实现可持续农业发展入选2018年度中国科学十大进展; 中国被子植物区系进化历史研究入选2018年度中国生命科学十大进展。以水稻为代表的农作物和果蔬等经济作物研究在国际上已呈现出明显的优势, 若干领域已从“追赶”状态跨越到“领跑”地位。该文对2018年中国科学家在植物科学若干领域取得的重要研究成果进行了概括性评述, 旨在全面追踪和报道当前中国植物科学领域的发展前沿和热点, 展示中国科学家所取得的杰出成就。     

2017年中国植物科学若干领域重要研究进展

2017年中国植物科学继续保持高速发展态势, 重大成果频出, 具体表现在中国植物学家在国际顶级学术期刊发表的文章数量平稳上升。中国植物科学领域的研究工作者成果精彩纷呈, 如新型广谱抗病机制的发现、水稻广谱抗病遗传基础及机制和疫霉菌诱发病害成灾机制研究等。2017年中国生命科学领域十大进展评选中, 有两项植物科学领域的研究成果入选。水稻生物学、进化与基因组学和激素生物学等领域学科发展突出。另外, 值得一提的是, 长期从事高等植物与代谢途径调控分子网络研究和水稻品种设计育种的李家洋院士的研究成果“水稻高产优质性状形成的分子机理及品种设计”荣获2017年国家自然科学一等奖。这一具有重大国际影响的开创性贡献标志着中国植物科学在该领域的国际科学前沿居于引领和卓越地位。该文对2017年中国本土科学家在植物科学若干领域取得的重要研究成果进行了系统梳理, 旨在全面追踪和报道当前中国植物科学领域发展的最新前沿动态, 与广大读者共同分享我国科学家所取得的辉煌成就。     

我国葫芦科植物离体培养研究进展

葫芦科植物包括多种瓜类蔬菜,对其进行离体培养研究具有重要的理论和实践意义.综述了国内在葫芦科植物器官培养、体细胞胚胎发生、花药培养、原生质体培养和体细胞杂交及离体遗传转化等方面取得的研究进展,并对葫芦科植物离体培养、遗传转化与育种的前景作了展望.     

Morphine-potentiated platelet aggregation in in vitro and platelet plug formation in in vivo experiments

The detailed mechanisms underlying morphine-signaling pathways in platelets remain obscure. Therefore, we systematically examined the influence of morphine on washed human platelets. In this study, washed human platelet suspensions were used for in vitro studies. Furthermore, platelet thrombus formation induced by irradiation of mesenteric venules with filtered light in mice pretreated with fluorescein sodium was used for an in vivo thrombotic study. Morphine concentration dependently (0.6, 1, and 5 microM) potentiated platelet aggregation and the ATP release reaction stimulated by agonists (i.e., collagen and U46619) in washed human platelets. Yohimbine (0.1 microM), a specific alpha(2)-adrenoceptor antagonist, markedly abolished the potentiation of morphine in platelet aggregation stimulated by agonists. Morphine also potentiated phosphoinositide breakdown and intracellular Ca(2+) mobilization in human platelets stimulated by collagen (1 microg/ml). Moreover, morphine (0.6-5 microM) markedly inhibited prostaglandin E(1) (10 microM)-induced cyclic AMP formation in human platelets, while yohimbine (0.1 microM) significantly reversed the inhibition of cyclic AMP by morphine (0.6 and 1 microM) in this study. The thrombin-evoked increase in pH(i) was markedly potentiated in the presence of morphine (1 and 5 microM). Morphine (2 and 5 mg/g) significantly shortened the time require to induce platelet plug formation in mesenteric venules. We concluded that morphine may exert its potentiation in platelet aggregation by binding to alpha(2)-adrenoceptors in human platelets, with a resulting inhibition of adenylate cyclase, thereby reducing intracellular cyclic AMP formation followed by increased activation of phospholipase C and the Na(+)/H(+) exchanger. This leads to increased intracellular Ca(2+) mobilization, and finally potentiation of platelet aggregation and of the ATP release reaction.     

Changes in aquatic vegetation in Rhine floodplain streams in Alsace in relation to disturbance

Abstract. Changes are described in aquatic vegetation in oligotrophic, groundwater-fed Rhine floodplain streams in Alsace (eastern France), resulting from disturbance. Disturbance factors include changes in nutrients, either permanent ones - effluent from a waste water treatment plant or trout hatcheries - or periodic ones: flooding. Regular inputs of high levels of phosphate and ammonia modified the macrophyte vegetation in these streams. The floristic composition, which was characteristic of oligotrophic waters upstream of the eutrophicated sector, changed to that of a eutrophic situation as originally found downstream. Periodic disturbance by floods which normally occur once a year, irregularly eutrophicates the small streams, causing the development of a mixture of eutrophic and oligotrophic species. Six macrophyte communities are distinguished, indicating different trophic levels. The aquatic vegetation is adapted to the variations of phosphate and ammonia levels. Hence, aquatic macrophytes can be used as bio-indicators of fluctuations in water nutrient levels in relation to the type of disturbance.     

Progress in glial cell studies in some laboratories in China

Glial cells in the central nervous system(CNS) consist of a heterogeneous population of cell types,each characterized by distinct morphological features,physiological properties,and specific markers.In contrast to the previous view that glial cells were passive elements in the brain,accumulating evidence suggests that glial cells are active participants in various brain functions and brain disorders.This review summarizes recent progress of glial cell studies from several groups in China,ranging from studie...