HBV病毒复制机制及慢性乙型肝炎药物靶点

乙型肝炎病毒(HBV)感染是一种严重影响公共卫生与人体健康的全球性流行性疾病,尽管乙肝防治已有很大提高,但仍缺乏高效的药物与手段。研究表明,肝损伤、肝衰竭程度与HBV及宿主免疫系统相互作用存在复杂关系。因而详细地探明HBV生命周期和感染过程,为研究HBV药物靶点和制定新的抗病毒策略提供前期坚实的基础,意义重大。该文详细介绍HBV病毒复制机制,并系统地阐述近年来新发现的和潜在的药物靶点,为制备新型的抗HBV药物提供参考。     

乙型肝炎病毒核心抗原在疫苗研究中的应用

乙型肝炎病毒核心抗原(hepatitis B virus core antigen,HBcAg)是乙型肝炎病毒的核衣壳蛋白,具有高度的免疫原性,能自我装配形成病毒样颗粒,并可接受外源基因的插入.HBcAg作为载体和佐剂已用于数十种病原微生物抗原表位的表达和新型疫苗的研发.此文就HBcAg的结构特点、免疫原性及其在疫苗研究中的应用进展作一综述.     

Relationship between histological prognosis of chronic hepatitis C and amount of hepatitis C virus core protein in serum

BACKGROUND: Hepatitis C virus (HCV) viraemia is one of the factors for histological prognosis of chronic hepatitis C. METHODS: One hundred and thirty-five patients who received hepatic biopsies twice at intervals of 5 years or longer were followed up for a mean of 9.7 +/- 4.0 years were studied retrospectively. The amount of HCV viraemia present was measured as the concentration of HCV core protein by using the fluorescence enzyme immunoassay method. RESULTS: Multiple-regression analysis, using deterioration of the histological stage as a dependent variable, showed that greater age (P = 0.041), higher stage of hepatic histology at the start of follow up (P = 0.029), and higher serum concentration of core protein (P < 0.001) were independent factors affecting the deterioration of the liver's histological stage. At follow up, no significant difference in histological stage was seen between patients with serum HCV core protein > or = 100 pg/mL (n = 60) and those with serum core protein < 100 pg/mL (n = 75). The histological grade in patients with high serum core-protein levels tended to be significantly worse and the deterioration rate of the histological stage was significantly higher than in those with low HCV core protein levels (68 vs 35%, P < 0.001). The mutation rate of the HCV envelope-2/non-structural 1 (E2/NS1) nucleotide region was compared in two patients who had high serum concentrations of HCV core protein and whose histological stage had deteriorated with two patients who had low serum concentrations of the core protein and whose histological stages remained unchanged. No significant difference in E2/NS1 mutation was found. CONCLUSIONS: The amount of HCV viraemia was suggested to be a significant factor for determining histological outcome in patients with chronic hepatitis C. The mutation rate in the E2/NS1 region did not seem to be associated with the prognosis of chronic hepatitis C.     

乙型肝炎病毒C基因启动子双变异患者中医证型特点研究

目的：探讨HBVC基因启动子（BCP）双变异慢性乙型肝炎患者的中医证型特点。方法：选择HBsAg阳性慢性乙型肝炎患者168例进行观察。中医证型分为湿热中阻、肝郁脾虚、肝肾阴虚、瘀血阻络、脾肾阳虚5型；BCP双变异检测，采用微板核酸杂交法。结果：BCP双变异的总检出率为36．31％（61／168），其中，湿热中阻型BCP双变异检出率最高（54．24％），与其他各型比较差异均有显著性意义（P〈0．052）；肝郁脾虚型BCP双变异检出率（36．36％）虽低于湿热中阻型（P〈0．025），但却明显高于肝肾阴虚型（13．04％）及瘀血阻络型（10．53％），且差异有显著性意义（P〈0．05）；肝肾阴虚与瘀血阻络两型BCP双变异检出率均较低，两者比较差异有显著性意义（P〉0．05）。结论：HBV BCP双变异的慢性乙型肝炎患者中医证型特点以湿热中阻为主，肝郁脾虚居次，临床治疗要重视清热利湿，舒肝健脾治法或方药的选用。     

改用血清原液检测抗-HBc的探索

以ELISA法检测抗,-HBc,且以血清原液(改良法)代替血清的1∶100倍X~2稀释液(常规法)。其结果,抗-HBc的阳性率从94.34％(2200/2332)增至98.94％(839/848),X~2=31.04,P<0.01.检测中未发现假阳性反应增加。与常规法相比,改良法提高了抗-HBc检测的灵敏度与特异度,是对ELISA药盒制备与检测技术的发展。     

Human papillomavirus was not detected by PCR using multiple consensus primer sets in esophageal adenocarcinomas in Chinese patients

The role of human papillomavirus (HPV) infection in the development of esophageal squamous cell carcinoma is well established; however, there are few reports on the role of HPV in esophageal adenocarcinoma. To evaluate the putative role of HPV infection in esophageal adenocarcinoma, 57 formalin‐fixed, paraffin‐embedded esophageal adenocarcinoma specimens were collected from four hospitals in Shanghai and Anyang, China, between 1999 and 2008. HPV DNA was analyzed using PCR with multiple sets of consensus primers for HPV, GP5+/6+, CPI/CPIIG, SPF₁₀, pU‐1M/pU2R, and pU31B/pU2R. Glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), the internal control, was amplified successfully in all 57 specimens. However, HPV amplification was not detected in any specimens with any of the consensus primer sets used. The present study indicates that HPV infection is not likely to be a major factor in the etiology of esophageal adenocarcinoma in the Chinese population. J. Med. Virol. 85: 1053–1057, 2013. © 2013 Wiley Periodicals, Inc.     

N-Terminal Sequence of a Core Protein from a Biglycan Isolated from Bovine Aorta

A biglycan was isolated from bovine aorta intima media by 4M guanidine HCl extraction of the tissue; the material was fractionated and purified by using isopycnic ultracentrifugation and DEAE Sephacel ion-exchange chromatography. Core proteins, resulting from digestion of the proteoglycan preparation with chondroitinase ABC, were resolved by SDS-polyacrylamide gel electrophoresis into three bands. The apparent molecular weight of the fast migrating major protein band was 47 kDa and the other slow-moving minor protein bands were 90 and 105 kDa. These proteins were recognized by a monoclonal anti-proteoglycan ΔDi-6S (MAb 3-B-3/Cl). The amino acid composition of 47 kDa core protein revealed a high content of aspartic acid, glutamic acid and leucine, similar to those found for biglycans isolated from bovine cartilage, rat vascular smooth muscle cell culture and human bone. The N-terminal sequence of 47 kDa core protein was determined as Asp-Glu-Glu-Ala-X-Gly-Ala-Glu-Thr-Thr-X-Gly-Ile-Pro-Asp which is identical to the sequence of bovine articular cartilage biglycan. The proteoglycan had two glycosaminoglycan chains.     

老年期抑郁症核心症状群的特尔菲法研究

目的:探讨在我国文化背景下老年期抑郁症的临床核心症状群,在此基础上制定症状清单.方法:采用文献法初步筛选出老年期抑郁症核心症状,并对各症状给予描述性定义.在此基础上采用专家咨询法(Delpbi法),按专家纳入标准严格选择咨询专家,最终选择中国大陆及香港、台湾地区30名老年精神科临床专家与老年心理学专家.进行两轮专家咨询,筛选出专家认可的老年期抑郁症核心症状群及其描述性定义.结果:筛选了12个有关老年期抑郁症核心症状条目,按症状重要程度的算数均数大小排列依次为(数值越大,表示专家认为该症状条目越重要)郁闷(9.57)、兴趣减退(9.43)、轻生观念或行为(9.36)、自责(9.00)、缺乏愉快体验(8.79)、无助绝望(8.57)、焦虑不安(8.29)、睡眠紊乱(8.21)、疲乏感(8.21)、躯体不适(8.07)、食欲或体重改变(8.00)、懒散迟缓(7.86).结论:专家咨询法筛选出郁闷、兴趣减退、轻生观念或行为等12个条目为老年期抑郁症临床核心症状群,并确定各症状条目的描述性定义.     

The structure of POMGNT2 provides new insights into the mechanism to determine the functional O-mannosylation site on α-dystroglycan

Defects in the O-mannosyl glycan of α-dystroglycan (α-DG) are associated with α-dystroglycanopathy, a group of congenital muscular dystrophies. While α-DG has many O-mannosylation sites, only the specific positions can be modified with the functional O-mannosyl glycan, namely, core M3-type glycan. POMGNT2 is a glycosyltransferase which adds β1,4-linked GlcNAc to the O-mannose (Man) residue to acquire core M3-type glycan. Although it is assumed that POMGNT2 extends the specific O-Man residues around particular amino acid sequences, the details are not well understood. Here, we determined a series of crystal structures of POMGNT2 with and without the acceptor O-mannosyl peptides and identified the critical interactions between POMGNT2 and the acceptor peptide. POMGNT2 has an N-terminal catalytic domain and a C-terminal fibronectin type III (FnIII) domain and forms a dimer. The acceptor peptide is sandwiched between the two protomers. The catalytic domain of one protomer recognizes the O-mannosylation site (TPT motif), and the FnIII domain of the other protomer recognizes the C-terminal region of the peptide. Structure-based mutational studies confirmed that amino acid residues of the catalytic domain interacting with mannose or the TPT motif are essential for POMGNT2 enzymatic activity. In addition, the FnIII domain is also essential for the activity and it interacts with the peptide mainly by hydrophobic interaction. Our study provides the first atomic-resolution insights into specific acceptor recognition by the FnIII domain of POMGNT2. The catalytic mechanism of POMGNT2 is proposed based on the structure.