应用TDI-FP技术分析宫颈癌组织HPV16 E7基因A647G点突变

模板指导的末端碱基掺入反应结合荧光偏振检测技术(template direct dye-terminator incorporation with fluorescence- polarization,TDI-FP) 是SNP检测新技术. 应用TDI-FP方法分析中国陕西HPV16阳性宫颈组织HPV16 E7基因第647位核苷酸A→G热点突变(即A647G),首先在HPV16阳性的91例宫颈癌及49例正常/宫颈炎妇女宫颈DNA标本中,PCR扩增含647位点在内的HPV16 E7部分基因, 然后将紧邻647位点5′端的寡核苷酸探针与PCR产物内的模板杂交,并延伸一个与647位点碱基互补的荧光标记碱基：TAMRA-ddTTP或R110-ddCTP. 用荧光偏振仪读取荧光偏振 (FP) 值,根据升高的相应FP值判断647位点碱基. 结果表明,宫颈组织HPV16 E7 A647G的总体检出率为35.71% (50/140). 宫颈癌组的A→G突变率为42.86% (39/91),显著高于正常/宫颈炎组22.45% (11/49) 的突变率 (x2 = 5.778, P = 0.016),两组间的OR值为2.59 (95% CI = 1.17~5.71). 提示TDI-FP 可用于HPV有意义点突变的分析;我国陕西地区妇女HPV 16 A647G突变率及其对宫颈癌的警示性与其他地区相比有明显差异,该地区携带此突变病毒株的妇女患宫颈癌的风险可能较高     

北京地区宫颈癌HPV16上游调控序列、E6、E7癌基因序列初步分析

为检测HPV16上游调控序列(Upstream regulatory region, URR)、E6、E7癌基因变异在北京地区宫颈癌患者癌组织中的分布特征, 探讨该地区宫颈癌发生同HPV16变异株间的相关性, 文章以提取的31例HPV16检测阳性宫颈癌组织DNA为模板, 设计针对性引物扩增URR、E6、E7 3个目的片段, PCR产物直接测序并通过GenBank对比分析变异和分支鉴定情况。在所分析的宫颈癌组织中, URR是突变频率最高的片段, 其次为E7, 最保守的序列为E6。共发现热突变位点8个, 分别为URR序列上G7521A(100%)、C7435G(96.77%)、C24T(45.16%)、A7729C(45.16%)、G7839A(45.16%); E6序列上T178G(41.94%); E7序列上A647G(45.16%)、T846C(45.16%)。HPV16分支分布频率最广的是As型(54.84%), 其次为E型(45.16%)。研究结果提示, HPV16URR序列上G7521A、A7729C、G7839A, E6序列上T178G、T350G, E7序列上A647G、G658A等位点的变异可能与病毒致癌潜能及宫颈癌的发生相关。北京地区宫颈癌患者中As和E型可能是两种最主要的HPV16分支, 这有可能会为HPV疫苗的研制和感染治疗提供有价值的信息。As型和E型病毒在不同年龄组和不同肿瘤分期组的患者中分布频率有差异, 这可能会为揭示宫颈癌年轻化趋势提供新的线索。     

云南HPV-16型E6、E7基因的突变分析

人乳头瘤病毒(Human papillomavirus,HPV)16型(HPV-16)是引起宫颈癌的一种主要高危型病毒,其2个致癌基因E6和E7的核酸序列变异可能会影响其对宿主细胞的致癌性,已有研究表明其序列突变呈现地域差异性。因此,研究不同地域HPV-16这2个基因的变化情况是宫颈癌流行病学调研的主要内容,也可为研究E6和E7的致癌性积累数据。研究以NCBI登录号为NC_001526.2的HPV-16型病毒的序列为参照,采用Neighbor-joining方法对云南地区74例HPV-16样本的E6、E7的DNA序列构建进化树,结果显示:只有亚洲和欧洲变异亚型,而没有发现非洲1、非洲2、亚-美洲和北美洲这4种变异亚型。DNA序列分析显示:E6的碱基突变以T178G(D25E,59.46%)和T350G(L83V,8.11%)为主,E7的碱基突变主要以A647G(N29S,59.46%)和T846C(同义突变,60.81%)为主。发现E6的新突变有A95G(同义突变,1.35%)和A135G(K11R,1.35%);E7的新突变有C625T(L22F,1.35%)、C627T(同义突变,12.16%)、G689A(G43E,1.35%)、T748G(S63A,1.35%)。此外还发现有一个共突变现象:T178G(D25E,59.46%)-A647G(N29S,59.46%)-T843C(同义突变,21.62%)-T846C(同义突变,60.81%)。     

新疆维吾尔族妇女宫颈癌组织中乳头瘤病毒16型E6基因的克隆和序列分析

为了分析新疆南部地区维吾尔族妇女宫颈癌组织中HPV16型E6基因结构特点，从中国新疆南部地区维吾尔族妇女宫颈癌活检组织标本中提取DNA，以宫颈癌活检组织标本DNA为模板进行PCR扩增，获得HPV16 E6基因，将其克隆到pUCm-T载体上，并对其进行基因全序列分析.PCR检测结果显示宫颈癌组织中HPV16 E6阳性率为82.35%（14/17）；测序结果显示，新疆株HPV16 E6基因全长456 bp，大小与德国标准株一致.E6基因的第247位碱基发生T→G突变，并由此引起所编码的氨基酸亦发生改变.上述结果表明，中国新疆南部地区维吾尔族妇女宫颈癌患者组织中HPV16 E6的基因结构与德国标准株HPV16 E6基因之间存在差异.     

云南地区宫颈癌组织中人乳头瘤病毒18型LCR基因变异特征分析

研究云南地区人乳头瘤病毒18型LCR基因在宫颈癌组织中的变异特点,通过系统发生分析探讨HPV-18变异株的分子流行特征,并通过转录因子结合位点的预测分析LCR变异对病毒感染可能造成的影响。本研究提取了云南地区74例女性宫颈癌组织样本中的DNA,通过PCR、测序、序列比对,分析了9个HPV-18LCR完整DNA序列的基因变异信息,并用Mega 7.0软件使用邻接法进行进化分析,使用JASPAR数据库对可能的转录因子结合位点进行预测。HPV-18LCR序列中发现T7258A、C7529A、G7563A、A7567C、T7592C、A7670T、T7736G、C7764T、C7857T、A41G、C54T、A89C和T104C13个核苷酸点突变,其中最常见变异位点是T7592C,其次是C7857T,突变频率分别为100%和44.4%。9个HPV-18LCR完整DNA序列分属于4个HPV-18LCR变异体,进化树分析显示云南地区流行的HPV-18主要为A系变异体(8个A1亚系,1个A4亚系),HPV-18LCR中T7592C、C7857T变异位于转录因子TBP、HOXA5的结合区域内。云南地区宫颈癌组织中主要流行的HPV-18为A系变异体,T7592C、C7857T是HPV-18LCR中主要变异位点。     

宫颈癌组织中人乳头瘤病毒16型E5基因的变异

探讨了HPV16 E5基因突变与宫颈癌发病的关系.应用银染聚合酶链反应-单链构象多态性(PCR-SSCP)分析对50份人宫颈癌活检标本进行基因突变的筛查.PCR检测显示,50例宫颈癌组织中HPV16 E5的检出率为30%(15/50),其中6例宫颈癌HPV16 E5扩增片段在行SSCP分析时发现有泳动变位,突变率为40%(6/15).可见HPV16 E5基因的突变在宫颈癌的发生过程中具有重要作用.     

C 蛋白基因多态性对脓毒血症患者血小板功能的影响

目的:探讨蛋白C基因突变及基因型频率分布和脓毒血症患者血小板功能及血清TXB2水平的相关性。方法:纳入112例脓毒血症患者,健康人群50例为对照组。采用PCR-RFLP法测定所有受试者蛋白C基因rs 17999808C/A位点和rs1799809位点基因型及突变率。入院24小时内测定脓毒血症患者血小板计数、最大聚集率及血清TXB2水平,并对其进行SOFA评分。结果:病例组和对照组rs17999808位点和rs1799809位点间基因型分布频率无统计学差异(P0.05)。rs 17999808基因型分布C/C占81.48%、C/A占12.96%、A/A占5.55%。rs1799809位点G/G占76.54%、G/C占15.43%、C/C占8.02%。rs17999808位点和rs1799809位点突变率分贝为12.03%、15.74%。病例死亡34例,死亡率30.35%。rs17999808位点突变纯合子患者(A/A)死亡率及SOFA评分明显增高,和野生纯合子及突变杂合子患者差异有统计学意义(P0.05)。rs17999808位点C/C野生纯合子患者血小板计数和TXB2浓度明显高于C/A和A/A患者,血小板聚集率低于后两者,差异有统计学意义(P0.05)。突变纯合子A/A患者较C/C、C/A患者两两相比,差异有统计学意义(P0.05)。rs17999809位点突变和TXB2浓度有相关性(P0.05)。结论:蛋白C基因rs17999808位点突变增加了脓毒血症患者死亡风险,这可能和其改变血小板功能有关。     

百日咳疫苗用菌株基因的遗传稳定性研究

目的对百日咳疫苗(pertussis vaccine)用菌株的主要保护性抗原基因序列的遗传稳定性进行研究,进一步验证此前一代测序的结果,为疫苗的安全性和有效性提供依据。方法采用第二代测序技术(next generation sequencing,NGS)对百日咳疫苗生产用菌株的主代代次(P4)、工作代次(P7)、疫苗代次(P13)及疫苗代次后连续传3代的第3代样品V3代次(P16)的主要抗原基因序列进行测序并分析。采用ELISA和Lowry法对百日咳疫苗生产用菌株各代次主要抗原组分进行抗原含量检测及比活性检测。结果百日咳毒素(pertussis toxin,PT) S1亚基上的8个等位基因氨基酸相对应的24个碱基位点中最高突变率为0.38%,其中疫苗代次最高突变位点(A2789C0.92%)在S5亚基上,其他各代次最高突变位点均不在S亚基上。PT全基因组最高突变率4%,且同一个位点不同代次的碱基突变呈不规律性,突变率没有随传代次数的增加而增高。百日咳黏附素(pertactin,PRN)的24个抗原表位中最高突变率在疫苗代次T951G位点,突变率为1.66%;其他位点的突变率均0.8%。全基因组中突变率最高的位点为V3代次C2025T,突变率为6.24%;各代次PRN全基因组最高突变率6.24%,且不在主要抗原表位区域内;在同一个位点不同代次的碱基突变没有随传代次数的增加而增高,呈不规律性。丝状血凝素(filamentous hemagglutinin,FHA)中B细胞抗原表位区中碱基最高突变率为0.98%(V3代次T6449G位点),其他代次均0.8%;全基因组各代次位点最高突变率为V3代次C7323G,突变率为9.89%;其余代次突变率均9.89%,且不在抗原表位区,同一个位点不同代次的碱基突变没有随传代次数的增加而增高,呈不规律性。PT的ELISA比活性平均值为0.532±0.100,最低限值为0.232。PRN的ELISA比活性平均值为0.885±0.110,最低限值为0.555。FHA的ELISA比活性平均值为0.701±0.170,最低限值为0.191,百日咳菌种抗原含量和比活性较稳定。结论传代过程中PT、PRN、FHA主要碱基位点突变率较低,说明百日咳菌种基因遗传稳定性好。     

110例维吾尔族及汉族乳腺癌中BRCA1基因突变及P53蛋白表达的研究

目的研究维吾尔族及汉族乳腺癌患者BRCA1基因突变及P53蛋白的表达。方法选取70例维吾尔族和40例汉族乳腺癌根治标本,对照组为32例维汉族乳腺良性病变(纤维腺病及纤维腺瘤)及乳腺癌旁非癌组织;运用PCR-SSCP和DNA序列测定的方法检测BRCA1基因突变及Evision二步法检测P53蛋白的表达。结果(1)110例维吾尔族及汉族乳腺癌中发现BRCA1突变的14个新位点。(2)110例维吾尔族及汉族乳腺癌BRCA1的突变率为10%,其中22例维吾尔族早发性乳腺癌(≤35岁)BRCA1突变率为31.82%,高于维吾尔族晚发性乳腺癌(P<0.01)。(3)110例维吾尔族及汉族乳腺癌中发现11例BRCA1基因核苷酸多态性位点。(4)BRCA1基因突变相关性乳腺癌中P53蛋白阳性表达率高于对照组,其淋巴结转移率高于对照组,其发病年龄小于对照组(P<0.01)。结论BRCA1基因突变与新疆维吾尔族早发性乳腺癌密切相关,且BRCA1突变相关性乳腺癌具有P53阳性率高、发病年龄趋于年轻化、淋巴结转移率高的趋势,这些特点有可能为基因检测前的筛选提供参考依据。     

人乳头瘤病毒16型(新疆株)E7基因的克隆与突变研究

目的：克隆分析人乳头瘤病毒16型(HPV16)新疆株的研基因;并对E7基因进行突变改造,以比较野生型与突变型HPV16E7基因的功能。方法：根据从中国新疆维吾尔族妇女宫颈癌活检组织标本中提取的DNA,进行PCR扩增获得HPV16E7基因,然后分别将其克隆到pMD18-T载体上进行DNA序列分析。根据HPV16E7基因的特点,分别设计点突变引物,用PCR的方法进行HPV16E7基因的点突变。结果：PCR检测显示扩增出HPV16(新疆株)E8基因;测序结果表明HPV16-XJ的研基因全长297bp,与德国标准株一致;利用设计突变位点的引物经PCR扩增,经序列测定后,分别得到了第70、172、271位碱基突变的HPV16E7基因;分别构建了野生型与单、双、三点突变的重组质粒pMD18-T-HPV16E7。结论：人乳头瘤病毒16型(新疆株)E7基因结构与德国标准株相同。HPV16E7基因多点突变的改造,为探索HPV16E7基因功能的变化和开展疫苗研究奠定了理论基础。     

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。     

Apoptosis in experimental myocardial infarction in situ and in the perfused heart in vitro

We report the appearance of apoptotic cells in experimental myocardial infarction (rabbit heart) in in situ and in vitro preparations. Apoptosis was recognized by intravital staining with Hoechst 33342 (Ho342), by nick-end labeling (TUNEL) and by DNA laddering. A steady rise in the relative number of apoptotic cardiomyocytes (apoptotic index) was noted in in situ preparations. Apoptosis was first noted 6 h after the onset of ischemia with its highest value occurring after 72 h. Apoptotic nuclei were absent in remote areas of the left and right ventricles. Apoptotic nuclei within the infarcted area showed diminished intensity of Ho342 fluorescence. Three days after ischemia, a border zone adjacent to the infarcted area consisting of apoptotic macrophages was recognized. A novel finding was the appearance of apoptotic cardiomyocytes in the isolated perfused ischemic heart. Occurring as early as 50 min after the onset of ischemia, a high apoptotic index was present adjacent to the ligature placed around the coronary artery. This observation provides the opportunity to selectively examine factors leading to apoptosis in the ischemic heart under controlled experimental conditions.     

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.