慢病毒感染方法构建稳定干涉PDRG1的HeLa细胞系

PDRG1(p53 and DNA-damage regulated 1)是实验室通过文库筛选发现的参与NF-kB信号通路调控的一个新基因。已知PDRG1在多种肿瘤中高表达,并参与p53信号通路;同时该基因受UV以及基因毒性等刺激调控。但其在NF-κB信号通路中作用尚未见报道,为了深入研究PDRG1对NF-κB信号通路的调控机理,构建了稳定干涉PDRG1的HeLa细胞系。选择了基于慢病毒载体pLKO.1的感染体系,该慢病毒体系可以同时感染分裂期与非分裂期的细胞,将目的基因干涉序列稳定整合至靶细胞基因组中;再经过抗生素压力筛选后在短时间内获得稳定干涉目的基因表达的细胞株。设计合成PDRG1干涉序列并克隆至pLKO.1载体,转染病毒包装细胞293TN后收集慢病毒上清感染HeLa细胞系,进一步经过嘌呤霉素压力筛选成功获得稳定表达PDRG1干涉序列的细胞株。该稳定细胞株的建立为PDRG1的功能研究提供了必要的实验工具。     

Helminths of some tree frogs of the families Hylidae and Phyllomedusidae in an Atlantic rainforest fragment,Brazil

Despite the fact that Brazil is the most-studied country regarding helminths of amphibians, only around 8% of Brazilian anurans have had at least one study made of their helminth fauna. Therefore, the aim of this study was to describe the helminth community of nine species of Atlantic Rainforest anurans of two different families, eight of them with no previous study, and six of which are endemic to Brazil. The analysed hosts for their parasites were: Dendropsophus minutus (n = 48), Scinax auratus (n = 36), D. branneri (n = 33), D. elegans (n = 26), Hypsiboas albomarginatus (n = 22), Pithecopus nordestinus (n = 19), D. decipiens (n = 12), D. haddadi (n = 11) and S. x-signatus (n = 11). A total of 781 helminths were collected from 106 (48.6%) of 218 analysed hosts, 656 Centrorhyncus sp. cystacanths and 125 nematodes: 76 adults (25 Cosmocerca sp.; three Cosmocerceidae gen. sp.; 20 Cosmocerca parva, 20 Cosmocercella phyllomedusae, five Aplectana sp., two Oswaldocruzia sp. and one Rhabdias sp.), 43 encysted larvae (nine Porrocaecum sp. and 34 Brevimulticaecum sp.) and six Physaloptera sp. larvae. Anurans may display many roles within the helminth life cycles, as they act as both predator and prey to a wide variety of animals. Consequently, we have found helminths that use anurans as definitive, intermediate and paratenic hosts. Opposing other surveys in which nematodes are the most prevalent and abundant parasites, acanthocephalans were the most prevalent taxa. These findings highlight the lack of knowledge regarding the helminth fauna of anurans and reveal many gaps with respect to their infection patterns in amphibians.     

Stability analysis of the bacteriophage ϕKMV lysin gp36C and its putative role during infection

The kinetic, thermodynamic and structural stability of gp36C, the virion-associated peptidoglycan hydrolase domain of bacteriophage ϕKMV, is analyzed. Recombinant gp36C is highly thermoresistant (k = 0.595 h⁻¹ at 95°C), but not thermostable (T_m = 50.2°C, ΔH_cal = 6.86 × 10⁴ cal mol⁻¹). However, aggregation influences kinetic stability in an unusual manner since aggregation is more pronounced at 55°C than at higher temperatures. Furthermore, gp36C reversibly unfolds in a two-state endothermic transition, and circular dichroism analysis shows that gp36C almost completely refolds after a 3-h heat treatment at 85°C. These properties are in agreement with gp36C being part of the extensible tail which is ejected in an unfolded state during phage infection. Received 24 April 2006; received after revision 26 May 2006; accepted 10 June 2006     

DpNPV多角体蛋白拉曼光谱的研究

研究了马尾松毛虫核型多角体病毒多角体蛋白的拉曼光谱。结果表明，ＤｐＮＰＶ多角体蛋白的二级结构主要为α螺旋和无规卷曲，后者含有大量的β回析，多角体蛋白的侧链Ｃ－Ｃ－Ｓ－Ｓ－Ｃ－Ｃ－构型为反式－扭曲－反式。     

计算机病毒分析及防治策略

针对计算机病毒的传播机制做了较深入的分析,提出了防治计算机病毒的几点措施。在多年操作经验基础上,对长城机的操作系统内核进行了改造。实践证明,这种防治计算机病毒策略是有效的。     

海口地区幼儿蛲虫感染调查

本文采用透明胶纸法先后对海口地区43所幼儿园的3611名2～7岁儿童进行了晓虫感染情况调查,总感染率为57.88％。43个幼儿园中,晓虫卵阳性率最低为32.0％(8/25),最高为83％(44/53);大多数幼儿园(30所占69.77％)感染率在50～60％～。不同类型的幼儿园中以机关事业单位组感染率较高(60.75％),农垦、港口系统组较低(53.56％)。有显著性差异(P<0.05);幼儿蛲虫的感染率随着年龄的增长而逐渐增高。6～岁组(65.96％)明显高于2～岁组(43.06％),各年龄组的感染率有显著性差异(P<0.01)。性别与感染率的高低无关(P>O.05),男女感染率分别为57.18％和58.75％     

基于数据挖掘的金莲花系列制剂治疗上呼吸道感染的作用机制

探讨金莲花4种制剂治疗上呼吸道感染疾病的作用机制.运用多个数据库建立金莲花系列制剂治疗上呼吸道感染的"成分-靶点-通路"网络."成分-靶点-通路"网络图表明金莲花治疗上呼吸道感染疾病的化学成分为槲皮素、刺槐素及β-谷甾醇,靶点为MAPK1、AKT1、TP53、TNF、IL6、STAT1、TGFB1、IFNG、NFKBIA、CXCL8、MYC、CASP8、IL10及CASP3,通路为癌症因子、乙型肝炎、NTF、肺结核、癌症蛋白聚糖、恰加斯病、弓形虫病、单纯疱疹感染、甲型流感及利什曼病信号通路.起治疗作用的最可能靶标和通路为TNF、MAPK1靶点和癌症因子通路.研究表明,金莲花4种制剂通过"多成分、多靶点、多通路"起到治疗上呼吸道感染疾病的作用.     

Dissection of cytotoxic and helper T cell responses

Cytotoxic (CD8⁺) and helper (CD4⁺) T cells play a crucial role in resolving infections by intracellular pathogens. The development of technologies to visualize antigen-specific T cell responses in mice and men over the past decade has allowed a dissection of the formation of adaptive T cell immunity. This review gives a brief overview of the currently used detection techniques and possible future additions. Furthermore, we discuss our current understanding of the formation of antigen-specific T cell responses, with particular attention to the similarities and differences in CD4⁺ and CD8⁺ T cell responses, the functional heterogeneity within responder T cell pools and the regulation of CD8⁺ T cell responses by dendritic cells and CD4⁺ helper T cells. Received 16 June 2005; received after revision 2 August 2005; accepted 15 August 2005     

幽门螺杆菌豚鼠动物模型的建立

采用哥伦比亚血琼脂固体培养基培养的幽门螺杆菌国际准菌株NCTC11637,用生理盐水稀释至109CFU/mL,采用6周龄、体重均在300~350 g的豚鼠20只,随机分为2组,每组对照鼠2只.实验鼠连续3次灌注幽门螺杆菌生理盐水稀释液,对照鼠同时灌注生理盐水,6、8周后处死检测.发现对照组豚鼠鼠胃中有Hp定值并呈现明显炎症反应,鼠胃上皮单个核细胞浸润,表明豚鼠对Hp NCTC11637敏感.首次在豚鼠中建立了稳定、可靠的幽门螺杆菌敏感动物模型,可为幽门螺杆菌疫菌的免疫学测定打下基础.