Chemokines: new ligands,receptors and activities

Chemokines, a large and growing family of structurally related proteins, were recognized originally for their ability to dictate the migration and activation of selected leukocyte populations. They now appear to have a number of additional roles, including T-cell development and activation, and angiogenesis. Current research interests in the area of chemokine biology were discussed at a recent meeting^*     

Regulation and expression of human Fabs under the control of the Escherichia coli arabinose promoter,PBAD

Background: The l-arabinose operon from E. coli contains an inducible promoter P_BAD which has been extensively studied for the control of gene expression. P_BAD has a number of potential advantages over P_lac, and has been used successfully to promote high level expression of recombinant proteins. Objectives: The aim of this study was to investigate P_BAD as an alternative system to P_lac for the bacterial expression of recombinant Fabs. Study design: The promoter P_BAD from the E. coli arabinose operon araBAD and the gene encoding the regulator of this promoter, were cloned into the phagemid expression vector MCO1. Expression of human recombinant tetanus toxoid (TT) and c-erb B2 Fabs under the control of P_BAD was compared at two induction temperatures with the same Fabs produced under the control of P_lac. Results: Expression of TT and c-erb B2 Fabs under the control of P_BAD was comparable to Fab expression from P_lac. However, highly expressed TT Fab under the control of P_BAD was localised to the soluble periplasmic fraction whereas under the control of P_lac, there was greater leakage of Fab into the culture supernatant. In addition, Fab expression from P_BAD could be more tightly repressed than from P_lac. Conclusion: P_BAD is a useful and cheaply inducible alternative to the more commonly used P_lac for the rapid expression of soluble recombinant human antibody fragments.     

人TRAF2新剪切体的鉴定与表达分析

目的:对TRAF2的新剪切体进行鉴定与表达分析.方法:以人脑库为模板,利用PCR扩增,电泳确定新剪切体的存在.再提取不同细胞与组织的总RNA,逆转录得到cD-NA后作为模板对两种不同剪切体的表达进行比较分析.结果:利用P1与P2引物对从人脑库扩增出1条约1 500 bp的条带,而利用P3与P4引物对则得到2条明显电泳带,通过测序表明其中1条包含TRAF2的第6外显子,另1条缺失了TRAF2的第6外显子.通过对新剪切体TRAF2Δ6与全长剪切体TRAF2的表达量比较表明在T47D中全长剪切体表达占优势;而在Hep3B、GC-1与MCF7中TRAT△6剪切体表达占优势;在HepG2、HBL100、A549与HeLa细胞中未发现两种剪切体的明显表达;在PANCI与SW480中两种剪切体表达量相近.在胎大脑与一级神经胶质瘤中TRAF2Δ6表达占优,而二级与三级神经胶质瘤中则全长剪切体TRAF2表达占优势.结论:人体TRAF2基因除可表达全长TRAF2 mRNA外,还可通过可变剪切表达缺失第6外显子的TRAF2Δ6 mRNA.而且这两种剪切体的表达存在细胞与组织特异性.     

聋生情绪智力的调查研究

目的调查聋生情绪智力的现状,并对聋健学生的情绪智力进行差异分析,为聋生的健康教育及管理工作提供科学依据。方法从2所特殊学校选取聋生195人,从2所普校选取健听学生423人作为调查对象,采用情绪智力量表(E IS),分别对两类学生进行评定和统计分析。结果①不同性别的聋生情绪智力差异不显著;②中专生的情绪智力和他人情绪调控得分显著低于大专生(t=-2.78,-3.06;P<0.01);③先天聋生的情绪智力、情绪感知及情绪运用上的得分显著低于后天聋生(t=-2.05,-2.36,P<0.05;t=-2.7,P<0.01);④与健听学生相比,聋生在情绪智力总分、情绪感知及对他人情绪的控制上的得分显著低于健听学生(t=-3.35,-5.82,-3.46;P<0.01)。结论聋生的情绪智力有待于进一步提高。     

行为决策中的“作为”与“不作为”:事件相关电位研究

目的:探讨作为与不作为两种不同决策行为下,差结果引起的大脑电位活动差异。方法:采用事件相关电位技术,让被试进行模拟股票购买操作,记录给予被试涨或跌反馈结果时的脑部电位。结果:观察到明显的反馈相关负波(feedback related negativity FRN)与P300成分,但未发现作为与不作为在两个成分上的显著差异,继而对作为与不作为两种情境下的差异波分析发现,在P300时间窗内,作为情境产生了更大的差异波。结论:作为与不作为两种决策情境导致的差结果在FRN时间窗内差异不显著,但P300时间窗内作为情境诱发了更大的差异波,这可能与作为情境下更多的正性情绪体验相关。     

初中农民工子女学习成绩与主观幸福感和孤独感的关系

目的:探讨初中农民工子女学习成绩、孤独感和主观幸福感之间的关系。方法:从福州市某区3所接收农民工子女的中学抽取初一、初二年级的农民工子女学生178人,进行UCLA孤独量表和GWB总体幸福感量表测验,并通过班主任收集学生的学习成绩等级。结果:除担心因子外,初中农民工子女的学习成绩与孤独感(r=-0.326)、满足兴趣(r=0.247)、精力(r=0.281)、心境(r=0.170)、控制(r=0.268)、松弛-紧张(r=0.273)之间相关显著;采用结构方程模型验证发现,初中农民工子女的孤独感在学习成绩与主观幸福感的关系中起部分中介作用。结论:初中农民工子女学习成绩不但能够直接影响他们的主观幸福感,还能通过影响他们的孤独感而间接影响主观幸福感。     

NSCs在OECs诱导下定向分化及神经元电生理特性研究

目的探索大鼠嗅鞘细胞（OECs）对神经干细胞（NSCs）分化的影响,并记录分化后神经元电生理特性。方法在无血清改良Eagle培养基（DMEM／F12）培养的NSCs中,加入OECs条件培养基,观察分化情况,巢蛋白（nestin）鉴定NSCs、神经丝蛋白200（NF200）鉴定神经元、膜片钳检测神经元电生理特性。结果OECs能促进NSCs分化为神经元,分化后的神经元记录到快速激活快速失活、能被河豚毒素（TTX）特异阻断的钠电流及慢激活慢失活、能被四乙基氯化铵（TEA）特异阻断的延迟整流性钾电流。结论OECs能诱导NSCs分化,分化后的神经元具有活跃的电生理特性,具有替代凋亡、坏死神经元的潜能。     

Protection against multiple influenza A virus subtypes by intranasal administration of recombinant nucleoprotein

Vaccination is a cost-effective way to control the influenza epidemic. Vaccines based on highly conserved antigens can provide protection against different influenza A strains and subtypes. In this study, the recombinant nucleoprotein (rNP) of the A/PR/8/34 (H1N1) influenza virus strain was effectively expressed using a prokaryotic expression system and then purified with a nickel-charged Sepharose affinity column as a candidate component for an influenza vaccine. The rNP was administered intranasally three times at 3-week intervals to female BALB/c mice in combination with an adjuvant (cholera toxin B subunit containing 0.2% of the whole toxin). Twenty-one days after the last immunization, the mice were challenged with homologous or heterologous influenza viruses at a lethal dose. The results showed that intranasal immunization of 10 μg rNP with adjuvant completely protected the immunized mice against the homologous influenza virus, and immunization with 100 μg rNP in combination with adjuvant provided good cross-protection against heterologous H5N1 and H9N2 avian influenza viruses. The results indicate that such a vaccine administered intranasally can induce mucosal and cell-mediated immunity, thus having the potential to control epidemics caused by new emerging influenza viruses.