GST-TAT-P53c融合蛋白的表达及对p53基因突变型肿瘤细胞的促凋亡作用

目的研究P53蛋白C端(P53c)对p53基因突变型肿瘤细胞SW480的促凋亡作用。方法用人类免疫缺陷病毒TAT蛋白的蛋白转导域(TAT)将P53c运载进入肿瘤细胞,用氧依赖性降解区域(ODD)控制P53c在组织中的稳定性。通过PCR方法制备TAT-ODD-p53c(TOPc),TAT-p53c(TPc)及p53c基因,与pGEX4T载体连接后在大肠杆菌中表达谷胱甘肽-S-转移酶(GST)-TAT-ODD-P53c(GST-TOPc),GST-TAT-P53c(GST-TPc)及GST-P53c等融合蛋白。免疫组化方法检测TAT蛋白运载融合蛋白穿过SW480细胞膜的作用,MTT法检测融合蛋白对SW480细胞活力的影响,流式细胞仪检测致SW480细胞凋亡作用。结果成功构建pGEX系列表达载体,并在大肠杆菌中可溶性表达。Western印迹结果表明,重组蛋白可以和GST单克隆抗体特异性结合。免疫组化显示GST-TPc,GST-TOPcm及GST-TOPc均能进入SW480细胞,GST-TPc能明显降低SW480细胞活性,导致SW480细胞凋亡。含ODD的融合蛋白在常氧环境中对肿瘤细胞有轻度促凋亡作用。结论TAT可以介导其融合蛋白跨越细胞膜。GST-TPc可引起p53突变型肿瘤细胞凋亡。     

2003-2006年北京市各类艾滋病抗体检测筛查实验室确认符合率对比分析

目的通过分析2003-2006年北京市各类艾滋病抗体检测筛查实验室送检样本的确认符合率，为制定适合北京市艾滋病防治工作需要的抗体检测策略提供科学依据。方法北京市艾滋病确证中心实验室收到的HIV抗体筛查实验室送检的样本，首先同时用两种酶联试剂筛查，其一为阳性或两者均阳性的样本在本次研究中定义为“筛查阳性”，并进行蛋白免疫印迹（WB）方法确认。将北京市的所有艾滋病抗体检测筛查实验室分为5类，通过比较各类筛查实验室2003-2006年的“筛查阳性”样本的确认阳性率、确认阴性率、确认可疑率，制定出针对不同筛查实验室的抗体检测策略。结果监管系统和定点医院的筛查阳性样本确认阳性率最高，而血液系统的确认可疑率最高。结论目前北京市虽然属于艾滋病低流行地区，但在监管系统和定点医院（性病、艾滋病治疗定点医院、戒毒治疗定点医院）存在相对集中的高危人群。监管系统和定点医院的艾滋病抗体筛查阳性受检人群，适用于《全国艾滋病检测技术规范（2004年）》的WB替代检测策略Ⅱ。普通医院和疾控系统的受检人群属一般人群，仍然坚持采用常规HIV抗体检测策略。血液系统应该采取严谨规范的检测策略，应引入病毒载量检测技术提高HIV抗体检测中的不确定样本的鉴别诊断水平。     

Relationship between selenium concentration in child hair and the distribution of Kashin-Beck Disease in Tibet,China

The focus of this study is to determine the relationship between selenium (Se) concentrations in child hair and the distribution of Kashin-Beck disease (KBD) in Tibet. The hair of children in typical KBD-affected areas and non-disease areas was collected, and its Se concentrations were measured by atomic fluorescent spectrometry. The Se concentrations in child hair were (0.13±0.04) and (0.18±0.07) μg/g respectively in KBD areas and non-disease areas respectively, which are significantly different. In areas supplemented with Se in Tibet, the Se concentration of hair in KBD-affected areas was higher than that in non-diseased areas, being (0.28±0.03) and (0.18±0.04) μg/g respectively. There is a close relationship between the Se concentrations in hair and KBD distribution. Se supplement increase the Se concentrations in the human body. Appropriate Se supplementation is important to prevent KBD in Tibet. Translated from Chinese Journal of Endemiology, 2006, 25(1): 70–72 [译自: 中国地方病学杂志]     

Studies of Coltivirus in China

Objective The purpose of this article is to review the developments of studies of Cohivirns in China.Data sources The data used in this review was obtained mainly from the studies of Cohivirns reported from 1990 to 2003 in China.Study selection Relevant articles on studies of Coltivirns in domestic and foreign literature were selected.Data extraction Data were maily extracted from the articles which are listed in the reference section of this review.Results Many Cohiviruses have been isolated not only from blood samples of patients with unknown fever or from cerebrospinal fluid of patients with encephalitis in Xishuangbanna area in Yunnan province, but also from mosquitoes collected in many areas in China. In some patients diagnosed as Japanese encephalitis or unknown fever, an increase of Cohivirns IgG antibody of fourfold, or more, has been detected using ELISA. Similarly,Cohivirns IgM antibody was positive in some patients with Japanese encephalitis or viral encephalitis. From most Chinese patients, except the northeastern, the isolates of Cohivirnses belong to subgroup B2, according to RT-PCR amplification of the ninth and twelfth segments of the isolates and sequence analysis of their amplicons.Some biological properties of Chinese Cohivirnses isolates are different from that of North American Cohivirnses.Conclusions The isolates of Cohiviruses from Chinese patients are one of the common agents causing viral encephalitis and unknown fever in summer-autumn season. It might be an important public health problem due to its high isolation rate and wide distribution in China. Mosquito is the main transmission vector of the virus.     

强化钙与维生素D牛奶对10～12岁女童体格发育的影响

目的 探讨补充强化钙与维生素D牛奶对我国10－12岁女童体格发育的影响。方法 1999年3月至2001年3月,我们进行了为期2年、设有对照的双盲干预实验。将北京市9所小学757名平均年龄10.1岁的女童分为对照组（259人,保持日常饮食）、A组（238人,除日常饮食外,饮用钙强化牛奶144ml/d)和B组（260人,除日常饮食外,饮用钙和维生素D强化牛奶144ml/d)。调查其食物摄入和体力活动情况。干预前、中、后测定研究对象的体重、身高、坐高及膝高。结果 干预2年后,A组和B组的身高增长率（9.52%和9.26%)显著高于对照组的8.59%;A组和B组的体重增长率（34.53%和35.38%)显著高于对照组的30.91%;A组的坐高增长率为9.21%,显著高于B组的8.58%,又高于对照组的7.87%;A组膝高的增长率为9.00%,显著高于B组（8.37%)和对照组（8.44%)。结论 长期补充强化钙与维生素D的牛奶可能会促进我国10－12岁女童的体格发育。     

Evolutionary selection associated with the multi-function of overlapping genes in the hepatitis B virus

It is a challenge to understand the discrete roles of each point mutation in viral evolution, but overlapping genes provide an excellent entrance for the investigation of this complicated process. We obtained 132 sequences from the largest overlapping region in the HBV genome. Based on the genetic divergence between genotypes B and C, we distinguished a set of related footprint mutations that are believed to be responsible for historical selection events. Examining the mutations in the functional domains, we found that the virus has adopted a coherent strategy in its evolutionary process that can be summarized as follows: (1) the distribution of mutations was non-random throughout the overlapping region, and more mutations were preserved in the sequence when one of the genes was under relaxed selection; (2) the viral domains were subject to different selective pressures; for instance, the PreS1 domain underwent a strict selection, whereas the overlapped Spacer domain was relatively relaxed with obvious tolerance of non-synonymous mutations with a high dN/dS ratio; (3) different selective pressures on two codon sites ultimately determined that every mutation persevered at a proper position. Taken together, the functional constraints of protein domains are believed to be primarily responsible for the different selection patterns exhibited by the distribution of mutations and amino acid changes in the region where overlapping genes reside.     

Epidemiological investigations of human rabies in China

Background  

The epidemic of rabies showed a rising trend in China in recent years. To identify the potential factors involved in the emergence, we investigated and analyzed the status and characteristics of human rabies between 1996 and 2008. Moreover, the status of rabies infection and vaccination in dogs, and prophylaxis of humans after rabies exposure were analyzed.     

Analysis of the genetic variability of the mumps SH gene in viruses circulating in the UK between 1996 and 2005

Genetic analysis (genotyping) of mumps viruses has been applied to the molecular epidemiology of mumps for over 10 years in the UK. To explore further the variation of mumps strains over time, in total, 965 sequences of the entire SH gene were analysed and compared, including 954 mumps virus strains collected in the UK between 1996 and 2005 were characterised as genotypes G2 (426), G5 (369), J (157) and F (2), which were compared with 11 F sequences found in China. Phylogenetic trees drawn for G2, G5 and J sequences showed that the diversities were greater between the sequences in earlier years (before 2001/2002) than those in later years and could be divided into two clusters within each of the three genotypes over the 10-year period. One transmission of G2, G5 and a J strain was sustained from earlier years with mutations and eventually became predominant strains. Divergences amongst the same genotype or sub-genotype was up to 4.6% for G2, 5.3% for G5 and 4.9% for J. Mutation rates per site per year based on the 316 nt of SH gene were 0.94, 1.3, 0.96 and 1.86 × 10^?2 for G2, G5, J and F respectively. The ratio of d_N/d_S was 0.556, 0.909, 0.357 and 0.811 calculated based on the sequences of G2, G5, J and F respectively. The results revealed that the possible mumps evolution process based on the SH gene was not driven by positive selection during the 10 years between 1996 and 2005.