广东省SARS流行株M基因序列分析

目的：测定广东省不同流行时期13份SARS病毒(SARS CoV)标本的M基因序列，通过分析该基因序列的变异情况，初步了解广东省SARS病毒在流行过程中是否发生了变异。方法：提取病毒RNA，用M基因特异引物进行RT-PCR，将产物纯化后直接测定核苷酸序列。结果：13份标本M基因核苷酸序列同源性很高，为99．7％～100％，M基因核苷酸序列只在2个位点(80和203位)发生变异，1株80位点的变化引起编码的氨基酸从苯丙氨酸(F)变为半胱氨酸(C)，3株203位变化为无义突变。结论：M基因核苷酸序列变异不大，初期和后期M基因核苷酸序列与流行高峰期的毒株相差1个碱基，但氨基酸序列相同；从香港感染病人分离的1株病毒M基因与广东本地感染分离株存在1个氨基酸的差异。     

利用cDNA微阵列技术筛选成年期与胚胎期睾丸差异表达基因——钙联接蛋白基因

目的 :用cDNA微阵列技术克隆和筛选成年期与胚胎期睾丸差异表达基因 ,以进行睾丸发育及精子发生的调控研究。　方法 :构建人睾丸cDNA芯片 ,分别用正常成人及胚胎睾丸的mRNA探针进行杂交 ,对成人和胚胎睾丸中差异表达的基因进行高流量的比较。　结果 :发现 1条成人睾丸高表达、胚胎低表达的基因———钙联接蛋白 (CLGN)基因。　结论 :运用cDNA微阵列方法可筛选到成年期与胚胎期睾丸差异表达基因     

勃起功能障碍基因治疗研究进展

近年来基因治疗被尝试用于勃起功能障碍(ED)治疗的动物实验,许多研究发现基因治疗方案对各种类型的ED均有一定的治疗作用。特别是在左旋精氨酸-一氧化氮-环磷酸鸟苷通路、离子通道、勃起神经和海绵体血管内皮细胞的修复保护等方面的基因治疗研究显示,基因治疗ED有一定的疗效。但应用基因治疗来治疗ED患者,目前仍有较多的困难,暂时无法应用于临床。本综述旨在对该领域的最新研究进展做一个简单的介绍和展望。     

Multipoint linkage analysis of spinocerebellar ataxia and markers on chromosome 6

Heterogeneity among the spinocerebellar ataxias (SCA) has been shown on clinical, biochemical, and genetic criteria. Among the autosomal dominant SCAs, several kindreds have shown loose linkage to the HLA loci on chromosome 6, while linkage in other kindreds has been rejected. The advent of multipoint linkage analysis allows the use of several marker loci simultaneously, thus increasing the amount of usable information. We have reanalyzed linkage data from a large kindred with SCA and provide evidence for a telomeric location of the SCA gene in this family. Knowledge of the relative gene location will ease the identification of the SCA gene by reducing the size of the chromosomal regions that must be examined.     

基因定量检测方法研究进展

基因定量检测已经成为研究基因组变异以及由于基因重组所引起的相关疾病的重要手段。大片段的基因组的重复和缺失可以引起致病突变。使用PCR和测序等定性检测方法很难探测到杂合状态的缺失和重复,因此探寻高效、可靠、灵敏的基因定量检测方法是当务之急。在过去的几年中已经相继出现了一些自动高效的技术方法。现在可用的基因定量方法大致可以分成3类:DNA印迹技术,细胞遗传学方法和以PCR扩增为基础的定量。本文对基因定量的最新进展作一综述,探讨其优缺点以期对定量研究方法的选择有所帮助。     

The predictive value of specific immunoglobulin E levels for the first diagnosis of cow''s milk allergy. A critical analysis of pediatric literature

Investigators have tried to identify a level of seric specific immunoglobulin E (IgE) that had a sufficient predictive value to diagnose a food allergy without having will resort to the food challenge. To search in literature, all the studies that have estimated the possibility to identify a level of seric specific cow milk IgE with a positive predictive value (PPV) of 95% for the first diagnosis of cow's milk allergy (CMA) in pediatric age. We have identified six studies, nearly all studies suffer from relevant methodological bias. Proposed cut-off are all different. The studied pediatric populations were highly selected. Also neglecting the methodological bias of the studies and the great difference of value between the proposed cut-off, it always remains to consider that the pre-test probability of having a CMA between the children enrolled in the six studies included in this review is particularly high. The likelihood ratio helps to transfer the results of a study on a diagnostic test just to our population, and it is more realistic rather than to entrust itself to the PPV or the negative predictive value, that are much influenced from the prevalence of the disease in the studied population.     

维生素E对高脂血症的影响

本文报道用高脂饲料造成家兔高脂血症的研究。经6周后,测定血脂、脂蛋白及血浆假胆硷脂酶等项指标,高脂组各项指标均明显高于对照组,但高脂加维生素E组的各项指标均低于高脂组,结果说明维生素E能降低兔的高脂血症。     

一种用于基因表达谱分析的基因芯片方法

目的：通过研究SLE患者外周血基因表达谱的改变，建立一种新型的基因芯片技术用于分子发病机理的研究。方法：提取总RNA，逆转录合成单链cDNA、双链cDNA，体外转录合成生物标记的cRNA与基因芯片进行杂交，通过抗体的检测标记荧光染料Cy3，基因芯片扫描仪进行图像扫描。结果：该方法有较高的重复性和稳定性，SLE患者与正常对照组相比较，鉴定出94个基因存在表达差异。结论：该方法能在较少起始标本量的情况下，有效地进行SLE致病基因的筛选，更好的理解SLE发生的分子机理，并且可在其它疾病研究中推广应用。     

B组轮状病毒WH-2株vp7基因的原核表达与抗体的制备

目的：在大肠杆菌中表达人B组轮状病毒WH-2株VP7蛋白并制备其兔抗血清。方法：根据B组轮状病毒（GBRV）WH-2株vp7基因的全序列设计引物,用PCR的方法扩增得到vp7基因的编码区。将其克隆到原核GST融合表达载体pGEX-KG内,转化大肠杆菌E.coliDH5α,IPTG诱导表达人B组轮状病毒WH-2株VP7蛋白,经SDS-PAGE分离纯化表达的蛋白免疫新西兰兔,制备人B组轮状病毒WH-2株VP7蛋白抗血清。结果：经鉴定确认,vp7基因以正确的方式插入到载体中,此重组表达载体经IPTG诱导后,可表达相对分子量为53.4 kDa的GST-VP7融合蛋白。制备的抗血清经同样诱导表达的表达载体pGEX-KG表达产物吸收后1：500倍稀释后用Western Blot分析,与53.4 kDa的GST-VP7融合蛋白获得特异性显色信号。结论：人B组轮状病毒WH-2株VP7蛋白成功在大肠杆菌中GST融合表达,所表达的蛋白和制备的抗体不但为研究结构与功能提供了物质基础,也为GBRV所引起的疾病预防、诊断和治疗等流行病学研究和临床诊断奠定了基础,具有重要实际应用价值。     

Transformation of Penicillium chrysogenum using the Aspergillus nidulans amdS gene as a dominant selective marker

Summary The Aspergillus nidulans acetamidase gene (amdS) has been used to transform Penicillium chrysogenum at low frequency. Several transformants were tested and shown to be mitotically stable. Southern blot analysis indicated that transforming DNA had integrated into the chromosomal DNA, possibly at multiple sites.