利用报告基因表达系统快速鉴定骨诱导活性材料

通过构建真核表达质粒,使增强型绿色荧光蛋白(Enhanced Green Fluorescent Protein, EGFP)报告基因的表达受骨形成相关转录因子Cbfa1基因启动子的调控,再用该质粒转染大鼠成肌细胞L6,建立稳定细胞株.在成骨培养基中诱导培养后,该细胞株呈现较明显的绿色荧光,表明细胞在经诱导的成骨分化过程中,Cbfa1基因表达增强,Cbfa1启动子驱动了EGFP的表达.将该细胞株接种到有较强骨诱导活性的羟基磷灰石/磷酸三钙(hydroxyapatitetricalcium phospha     

MGB probe assay for rapid detection of mtDNAl1778 mutation in the Chinese LHON patients by real-time PCR

Objective： Leber＇s hereditary optic neuropathy （LHON） is a maternally inherited degeneration of the optic nerve caused by point mutations of mitochondrial DNA （mtDNA）. Many unsolved questions regarding the penetrance and pathophysiological mechanism of LHON demand efficient and reliable mutation testing. This study aims to develop a minor groove binder （MGB） probe assay for rapid detection of mtDNA11778 mutation and heteroplasmy in Chinese LHON patients by real-time polymerase chain reaction （PCR）. Methods： Forty-eight patients suspected of having LHON and their maternal relatives underwent a molecular genetic evaluation, with 20 normal individuals as a control group at the same time. A real-time PCR involving two MGB probes was used to detect the mtDNA 1 1778 mutation and heteroplasmy. A linear standard curve was obtained by pUCmLHONG and pUCmLHONA clones. Results： All 48 LHON patients and their maternal relatives were positive for rntDNA11778 mutation in our assay, 27 heteroplasmic and 21 homoplasmic. Eighteen cases did not show an occurrence of the disease, while 9 developed the disease among the 27 heteroplasmic mutation cases. Eleven did not show an occurrence of the disease, while 10 cases developed the disease among 21 homoplasmic mutation cases. There was a significant difference in the incidence between the heteroplasmic and the homoplasmic mutation types. The time needed for running a real-time PCR assay was only 80 min. Conclusion： This real-time PCR assay is a rapid, reliable method for mtDNA mutation detection as well as heteroplasmy quantification. Detecting this ratio is very important for predicting phenotypic expression of unaffected carriers.     

快速检测猪瘟兔化弱毒疫苗株的TaqMan荧光定量RT-PCR方法的建立

在猪瘟病毒兔化弱毒疫苗株（HCLV）的5′端非编码区设计一对引物和一条TaqMan探针,通过优化反应条件,成功建立了特异性检测HCLV的荧光定量RT-PCR方法．结果表明：该方法检测的最低拷贝数为45拷贝／μL,灵敏度比普通PCR方法高10^4倍,在较广的范围内（4．5×10^1-4．5×10^6拷贝／μL）有良好的线性关系（r=0．994）;分别以乙型脑炎病毒、猪繁殖与呼吸综合征病毒、副猪嗜血杆菌、牛病毒性腹泻,黏膜病病毒作为模板进行TaqMan RT-PCR扩增,未出现阳性信号：4个不同浓度标准品组内试验变异系数为1．90％～5．82％,组间试验变异系数为4．02％～5．69％：HCLV3个cDNA样本组内试验变异系数为3．72％～4．93％;组间试验变异系数为2．99％～4．02％．该方法具有很好的灵敏性、特异性及稳定性,能够快速准确定量检测HCLV,为HCLV疫苗的研制、猪瘟病毒分子生物学等方面研究提供了一种快捷有效的工具．     

一种快速测定灵芝孢子粉抗氧化性的方法

采用紫外分光光度法,以Fenton反应为基础,建立灵芝孢子粉抗氧化性快速准确测定的新方法.以水杨酸与Fenton反应产生的羟基自由基反应生成的二羟基苯甲酸在530nm处有最大吸收的原理,确立最佳反应条件.在此条件下,以抗坏血酸作为羟基自由基的清除剂,获得了标准曲线和标准对照图,为灵芝孢子粉抗氧性的快速检测提供了标准思路.在此最佳条件下,采用超声波提取法对灵芝孢子粉进行多糖的提取,将多糖提取液或者灵芝孢子粉颗粒加入反应体系中,反应后测其在530nm处的吸光度,即可快速获知其抗氧化性.同时,比较了破壁和未破壁孢子粉提取液和孢子粉颗粒的抗氧化性差异,结果表明破壁后的抗氧化性较未破壁高10%.证明此快速测定方法的实用性.本方法操作简单,所用试剂均无毒副作用,为灵芝孢子粉抗氧化性的快速测定提供一个较快速且准确的方法.     

一种快速微量的非放射性核糖体失活蛋白活性检测方法

建立了一种非放射性的利用兔网织红细胞裂解液（Rabbit Reticulocyte Lysate）无细胞翻译系统和荧光素酶检测系统（Luciferase Assay System）的核糖体失活蛋白检测方法,快速检测了两种方法提取的麻疯树核糖体失活蛋白（RIPs）Curcin的无细胞蛋白质翻译抑制活性,测得离子交换层析法纯化Curcin的IC50＝0.045±0.009nmol/L,分子筛层析纯化Curcin的IC50＝0.217±0.026nmol/L;该方法避免了放射性同位素的使用,使检测过程简便、快速     

Metagenomic analysis of a permafrost microbial community reveals a rapid response to thaw

Permafrost contains an estimated 1672?Pg carbon (C), an amount roughly equivalent to the total currently contained within land plants and the atmosphere. This reservoir of C is vulnerable to decomposition as rising global temperatures cause the permafrost to thaw. During thaw, trapped organic matter may become more accessible for microbial degradation and result in greenhouse gas emissions. Despite recent advances in the use of molecular tools to study permafrost microbial communities, their response to thaw remains unclear. Here we use deep metagenomic sequencing to determine the impact of thaw on microbial phylogenetic and functional genes, and relate these data to measurements of methane emissions. Metagenomics, the direct sequencing of DNA from the environment, allows the examination of whole biochemical pathways and associated processes, as opposed to individual pieces of the metabolic puzzle. Our metagenome analyses reveal that during transition from a frozen to a thawed state there are rapid shifts in many microbial, phylogenetic and functional gene abundances and pathways. After one week of incubation at 5?°C, permafrost metagenomes converge to be more similar to each other than while they are frozen. We find that multiple genes involved in cycling of C and nitrogen shift rapidly during thaw. We also construct the first draft genome from a complex soil metagenome, which corresponds to a novel methanogen. Methane previously accumulated in permafrost is released during thaw and subsequently consumed by methanotrophic bacteria. Together these data point towards the importance of rapid cycling of methane and nitrogen in thawing permafrost.     

SCN1A基因4号外显子突变筛选

目的：探讨癫痫人群及正常人群SCN1A基因突变情况．方法：共采集癫痫病人血液181份、癫痫病人脑组织38份,正常人血液120份．提取基因组DNA,针对SCN1A基因4号外显子设计1对引物,进行聚合酶链反应（PCR）扩增,琼脂糖凝胶电泳,选取适合条件的PCR产物进行聚丙烯酰胺凝胶电泳,进行单链构象多态性分析,对个别PCR产物进行双向测序．结果：所有样本进行SCN1A的4号外显子筛选时,均未发现异常带出现．选取2例癫痫病人血液的PCR产物测序结果与基因组序列相比对,也未发现碱基改变．结论：癫痫是一种复杂综合征,研究的339癫痫患者中未发现SCN1A基因4号外显子突变．     

GEP的网络入侵检测规则约束及演化策略

针对基于演化计算的网络入侵检测存在演化过程时间和空间开销大、误警率高等问题,采用基因表达式编程(GEP)模式表示入侵检测规则,提出针对GEP入侵检测规则的约束文法,并通过增加规则约束判断及处理过程改进GEP基本演化流程,生成满足约束的入侵检测规则.最后使用KDD CUP′99 DATA对该策略进行评估,所生成规则只需2个网络属性,在测试集中检测率为89.79%,误警率为0.41%.实验结果表明:在较小种群和低演化代数内,GEP规则约束和演化策略获得的规则有效而简洁,可检测到未知入侵,在保持较高检测率的同时可获得低误警率.     

人GABRA1实时荧光定量TaqMan PCR检测方法的建立

根据GenBank上人GABRA1基因的序列,设计并合成特异性的引物及探针,采用TaqMan探针法建立了荧光定量PCR法,以常规PCR产物为标准品,建立标准曲线．结果表明,标准曲线Ct值检测范围为12．07-32．72,相关系数为0．999,扩增效率为96．4%.建立的GABRA1TaqMan探针实时荧光定量方法具有线性范围广、扩增效率高、检测时间短、敏感性高等特点．     

鸭GAPDH基因实时荧光定量PCR方法的建立

本研究旨在建立鸭GAPDH基因的real-time PCR技术,为鸭功能基因mRNA水平的定量分析提供有用的方法学基础.根据GenBank中鸭GAPDH基因的序列设计引物,建立了基于SYBR Green I染料技术的real-time PCR方法.结果表明,所建立的方法具有快速、高通量、线性范围广以及重复性强等特点.研究结果为鸭GAPDH作为内参基因用于鸭相关基因定量表达分析奠定了基础.     

应用液态悬浮芯片技术建立HPV基因分型方法

目的 应用液态悬浮芯片技术,建立一种新的人乳头瘤病毒(HPV)基因分型方法.方法 应用通用引物从HPV基因组中扩增出目的片断,与13型荧光微球偶联探针杂交,通过LuminexTM100检测HPV的型别.结果 检测十三型标准株质粒,对单一标准品和混合标准品均可准确分型.结论 初步建立了高通量、快速、可靠、适用于临床的人乳头瘤病毒分型基因诊断方法.     

胡萝卜DcPS基因的克隆、进化及根发育中表达分析

补骨素合成酶(PS)是胡萝卜营养物质补骨素生物合成的关键酶.从'黑田五寸'胡萝卜中克隆得到DcPS基因,对其进行了进化和在胡萝卜根发育过程中表达水平分析.结果表明,DcPS基因长1518 bp,编码氨基酸505 aa,属于细胞色素P450超级基因家族.其氨基酸序列含有10个明显的特征,其中含有1个跨膜区,为亲水性蛋白....