绵羊红细胞的质量对静脉注射用人免疫球蛋白抗补体活性测定的影响

为了分析IVIG抗补体活性测定出现负值与绵羊红细胞质量的关系。采用CH50试验测定IVIG ACA时,在被检样品和其他试验条件相同的情况下,比较了被污染的和未污染的绵羊红细胞对IVIG抗补体活性测定的影响。结果显示,使用被污染的绵羊红细胞(作为试验材料时所得的)检测10份样品ACA(%)均为负值;使用未污染的绵羊红细胞未出现负值。提示被污染的绵羊红细胞干扰了抗补体活性测定,从而引起CH50试验结果出现偏差。     

泡沙参同工酶基因位点的遗传分析

利用聚丙烯酰胺凝胶电泳技术 ,对来自天然群体 (居群 )的泡沙参 (Adenophora potaninii Korsh.)及其人工杂交子代进行了 8种同工酶的电泳检测和谱带遗传分析 ,以确定编码这些酶系统的基因位点和等位基因。选用 4种不同的凝胶缓冲系统 ,对下列不同酶系统进行了酶谱的遗传分析 :天冬氨酸转氨酶 (AAT)、酯酶 (EST)、甲酸脱氢酶 (FDH)、谷氨酸脱氢酶 (GDH)、异柠檬酸脱氢酶 (IDH)、乳酸脱氢酶(LDH)、苹果酸酶 (ME)和超氧化物歧化酶 (SOD)。结果表明 ,这 8种酶系统至少由 1 8个基因位点编码 ,其中 1 2个位点为遗传稳定的等位酶位点 ,是可靠的遗传标记。酶谱的分离式样表明 ,EST为单聚体结构 ,AAT、FDH、IDH、SOD为二聚体结构 ,GDH为六聚体结构。最后对同工酶的器官和发育特异性以及同工酶基因位点的遗传分析进行了讨论     

原始生殖细胞发生的机制

生殖细胞的发生是发育和遗传的基础。在几乎所有哺乳动物中,原始生殖细胞（primordial germ cell,PGC）均由近端上胚层体细胞在周边细胞特定的信号诱导下特化而成。目前的研究已经发现一些与生殖细胞特化有关的信号分子和关键转录调控元件,以及特化后生殖细胞获得的与体细胞不同的生物特性。生殖细胞的特化是一个结合了体细胞发育程序的抑制、细胞多能性程序的启动和全基因组表观遗传重编程三个方面的动态的复杂过程。多能性干细胞（胚胎干细胞或诱导型多能干细胞）具有发育全能性,能分化为机体任何一种细胞类型,包括生殖细胞。利用多能性干细胞体外分化形成生殖细胞有助于深入系统地研究配子发生的调控机制,为干细胞在不育症治疗方面的应用带来新希望。     

一种定量检测人血清高敏C反应蛋白的化学发光免疫方法

旨在建立一种可定量检测人血清高敏CRP的化学发光检测方法 (High-sensitivity C-reactive protein quantifiable chemiluminescent immunoassay,hs-CRP CLIA)。首先利用亲和层析和离子交换层析技术从肝硬化病人腹水中纯化出高纯度的天然CRP作为免疫原制备了22株CRP单克隆抗体 (单抗),其中13株单抗在磷酸胆碱配体捕获ELISA中呈阳性,然后利用方正滴定法筛选出单抗10C5和10C11建立了hs-CRP CLIA。试剂盒评估结果显示：该方法对血清中干扰物质IgG、血红蛋白、甘油三酯等无非特异性反应;该方法检测灵敏度高,在0.04~20.38 mg/L范围内定量检测人血清CRP标准品呈良好线性关系 (R2＞0.993);该方法准确性高、可重复性好,平均回收率为99％,批内差为4.2％~5.8％,批间差为9.0％~11.5％;该方法与进口商品化高敏CRP ELISA试剂盒平行比较检测90份血清标本,结果显示两者有良好的可比性 (r=0.968)。综上,建立的hs-CRP CLIA是一种准确、可靠、可定量的高灵敏C反应蛋白检测方法,该方法的临床应用,有利于改善我国心脏病风险评估及肠炎性疾病预后判断。     

巨细胞病毒中性红斑定量试验与高滴度病毒的制备

在巨细胞病毒(CMV)的研究中常需对病毒定量。CMV需低滴度传代,否则会产生没有感染性的缺损病毒颗粒;CMV的抗原性受其感染量的影响;检测CMV中和抗体或纯化病毒都需具备病毒空斑定量基础。另外,制备高感染滴度的无细胞病毒(游离病毒)是对CMV进行分子生物学研究的前提。本文建立了CMV微量板法中性红斑定量技术并比较了几种制备无细胞CMV的方法。     

A Bipartite Network-based Method for Prediction of Long Non-coding RNA–protein Interactions

As one large class of non-coding RNAs(nc RNAs), long nc RNAs(lncRNAs) have gained considerable attention in recent years. Mutations and dysfunction of lnc RNAs have been implicated in human disorders. Many lnc RNAs exert their effects through interactions with the corresponding RNA-binding proteins. Several computational approaches have been developed, but only few are able to perform the prediction of these interactions from a network-based point of view. Here,we introduce a computational method named lnc RNA–protein bipartite network inference(LPBNI). LPBNI aims to identify potential lnc RNA–interacting proteins, by making full use of the known lnc RNA–protein interactions. Leave-one-out cross validation(LOOCV) test shows that LPBNI significantly outperforms other network-based methods, including random walk(RWR)and protein-based collaborative filtering(Pro CF). Furthermore, a case study was performed to demonstrate the performance of LPBNI using real data in predicting potential lnc RNA–interacting proteins.     

基因组数据库简介

本文以北京大学生物信息中心安装的3个国际著名基因组数据库GDB、GenoList和Ensembl为基础,介绍目前常用的基因组数据库,包括这些数据数据库的内容、数据格式、使用方法,以及用于构建上述数据库的数据库管理系统。 Abstract:A brief introduction to the genome databases GDB,GenoList and Ensembl is given.These databases,mirrored and maintained at the Centre of Bioinformatics,Peking University,provide useful information for genome research.     

T-DNA插入水稻群体中卷叶突变体R1-A2的遗传分析

在根癌农杆菌介导的T-DNA(携带有除草剂Basta抗性基因bar和Ds因子)转化中花11水稻群体中,获得了一个叶片发生明显内卷的突变体R1-A。经过连续三代的分离鉴定,获得突变体的纯合株(R1-A2),并与中花11号进行杂交,在调查的36个F_1植株中,全部表现为卷叶,并对Basta除草剂都表现为抗性。在852个F_2单株中,卷叶为645株,正常叶207株,卷叶和正常叶的比例为3:1,其中,卷叶株均对Basta表现抗性,正常叶株均对Basta表现敏感,表明卷叶性状和Basta抗性存在着共分离关系。用扩增Ds因子的引物,对F_2中45个卷叶抗性株进行PCR鉴定,都获得预期长度的Ds因子片段,进一步表明在这些卷叶的植株中都有T-DNA的插入;而30个正常叶敏感株都不能检测到Ds的特征片段。在以卷叶突变(R1-A2)为回交亲本的F_1B_1植株中,全部植株表现卷叶;在以中花11号为回交亲本的F_1B_1植株中,卷叶和正常叶植株的分离比为1:1。上述结果表明该卷叶突变是个显性突变,受一个基因所控制,且该基因的突变与T-DNA的插入有关。     

Superoxide anion burst and taxol production induced by Ce in suspension cultures of Taxus cuspidata

Generation of reactive oxygen species (ROS) induced by Ce⁴⁺ in suspension cultures of Taxus cuspidata was investigated. The burst of superoxide anions (O₂√⁻) occurred rapidly after the addition of Ce⁴⁺ and reached maximum at 4.3 h, while the total level of the cellular reactive oxygen species maintained unchanged. The intracellular superoxide dismutase (SOD) and catalase (CAT) were activated while the intra/extracellular peroxidases (PODs) were inhibited accompanying the O₂√⁻ burst. The pretreatment of the suspension cultures with diphenylene iodonium (DPI), a suicide inhibitor of the NADPH oxidase, blocked the O₂√⁻ burst, inhibiting the cell apoptosis and taxol production induced by Ce⁴⁺. These results show that NADPH oxidase played a key role in O₂√⁻ burst and O₂√⁻ served as a mediator of Ce⁴⁺ for cell apoptosis and taxol production. The pretreatments of the suspension cultures with anthracene-9-carboxylate, an ion-channel blocker, nifedipine, a Ca²⁺-channel blocker, neomycin, a phospholipase C (PLC) inhibitor, or suramin, a G-protein inhibitor, decreased O₂√⁻ burst induced by Ce⁴⁺. It is thus inferred that Ce⁴⁺-induced O₂√⁻ burst, which mediated cell apoptosis and taxol production by activating the ion-channels, PLC, G-proteins and NADPH oxidase.     

Ethanol fermentation with Kluyveromyces marxianus from Jerusalem artichoke grown in salina and irrigated with a mixture of seawater and freshwater

Aims: To study fuel ethanol fermentation with Kluyveromyces marxianus ATCC8554 from Jerusalem artichoke (Helianthus tuberosus) grown in salina and irrigated with a mixture of seawater and freshwater. Methods and Results: The growth and ethanol fermentation of K. marxianus ATCC8554 were studied using inulin as substrate. The activity of inulinase, which attributes to the hydrolysis of inulin, the main carbohydrate in Jerusalem artichoke, was monitored. The optimum temperatures were 38°C for growth and inulinase production, and 35°C for ethanol fermentation. Aeration was not necessary for ethanol fermentation with the K. marxianus from inulin. Then, the fresh Jerusalem artichoke tubers grown in salina and irrigated with 25% and 50% seawater were further examined for ethanol fermentation with the K. marxianus, and a higher ethanol yield was achieved for the Jerusalem artichoke tuber irrigated with 25% seawater. Furthermore, the dry meal of the Jerusalem artichoke tubers irrigated with 25% seawater was examined for ethanol fermentation at three solid concentrations of 200, 225 and 250 g l^?1, and the highest ethanol yield of 0·467, or 91·5% of the theoretical value of 0·511, was achieved for the slurry with a solid concentration of 200 g l^?1. Conclusions: Halophilic Jerusalem artichoke can be used for fuel ethanol production. Significance and Impact of the Study: Halophilic Jerusalem artichoke, not competing with grain crops for arable land, is a sustainable feedstock for fuel ethanol production.