The haplotype block, NFKBIL1-ATP6V1G2-BAT1-MICB-MICA, within the class III-class I boundary region of the human major histocompatibility complex may control susceptibility to hepatitis C virus-associated dilated cardiomyopathy

Cardiomyopathy is a heart muscle disease with impaired stretch response that can result in severe heart failure and sudden death. A small proportion of hepatitis C virus (HCV)-infected patients may be predisposed to develop dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). The molecular mechanisms involved in the predisposition remain unknown due in part to the lack of information on their genetic background. Because the human leukocyte antigen (HLA) region has a pivotal role in controlling the susceptibility to HCV-induced liver disease, we hypothesized that particular HLA alleles and/or non-HLA gene alleles within the human major histocompatibility complex (MHC) genomic region might control the predisposition to HCV-associated DCM (HCV-DCM) and/or HCV-associated HCM (HCV-HCM). Here, we present mapping results of the MHC-related susceptibility gene locus for HCV-associated cardiomyopathy by analyzing microsatellite and single nucleotide polymorphism markers. To delineate the susceptibility locus, we genotyped 44 polymorphic markers scattered across the entire MHC region in a total of 59 patients (21 HCV-DCM and 38 HCV-HCM) and 120 controls. We mapped HCV-DCM susceptibility to a non-HLA gene locus spanning from NFKBIL1 to MICA gene loci within the MHC class III-class I boundary region. Our results showed that HCV-DCM was more strongly associated with alleles of the non-HLA genes rather than the HLA genes themselves. In addition, no significant association was found between the MHC markers and HCV-HCM. This marked difference in the MHC-related disease susceptibility for HCV- associated cardiomyopathy strongly suggests that the development of HCV- DCM and HCV-HCM is under the control of different pathogenic mechanisms.     

家兔葡萄球菌性发热及其热限的探讨

采用加热杀死的白色葡萄球菌菌体作激活物,给家兔耳缘静脉注射,观察剂量-发热效应,血浆EP的活性以及血浆和脑脊液中cAMP含量变化。结果表明,在一定的范围内,随剂量递增,发热效应相应加强,但达到一定浓度,可出现热限;发热时,血浆可检出循环EP;血浆致热活性,脑脊液cAMP含量随发热效应增强而升高,出现热限时,则不再升高。作者推论:cAMP可能是葡萄球菌性发热的重要中枢介质;EP的产生释放受限和体温调节中枢内cAMP的产生受限可能是构成葡萄球菌性热限的重要因素。     

Complete Nucleotide Sequence Analysis of a Western Pacific Dengue-1 Virus Strain

We have determined the complete nucleotide sequence and the deduced amino acid polypeptide sequence of the genome of a dengue-1 (DEN-1) virus strain isolated from a patient on Nauru in the Western Pacific in 1974 (West Pac 74). The complete genome is 10,735 nucleotides in length and contains a single long open reading frame of 10,176 nucleotides encoding a polyprotein of 3392 amino acids. When compared to DEN-1 Singapore S275/90, the nucleotide and amino acid sequence homology are 94% and 97.8%, respectively. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genotype,serotype, and phylogenetic characterization of the complete genome sequence of hepatitis B virus isolates from Malawian chronic carriers of the virus

Hepatitis B virus (HBV) genotypes have distinct geographical distribution. HBV sequences among hepatitis B carriers in Malawi have not been evaluated thus far. HBsAg serotype and genotype of HBV was determined in 20 serum samples from Malawian chronic HBV carriers, and two complete genomes and 13 entire pre-S2/S genes were sequenced directly. Genotype A HBV isolates were found in all of the samples, and serotype with adw2 and ayw2 were detected in three and 17 samples, respectively. In phylogenetic analyses, two complete genomes were classified into a subgroup A' that was described previously in South African isolates of the virus, and were separated from HBV isolates in Western countries with nucleotide differences ranging from 4.1-6.2%. The separation of subgroup A' was also evident in the tree topology of the entire pre-S1/S2, X and precore/core region, but not evident in the small-S region. The nucleotide divergences in subgroup A' were higher than those among genotype A without subgroup A' in the complete genomes as well as each of four open reading frames. All of the 13 pre-S2/S sequences were classified into the subgroup A', and clustered with known HBV isolates with ayw2 in carriers from South Africa and Zimbabwe. Three amino acids in the pre-S2/S gene were characteristic of subgroup A' with ayw2. In conclusion, unique HBV isolates of subgroup A' with ayw2 are prevalent in Malawi, and subgroup A' with a relatively higher nucleotide diversity may be a HBV isolate characteristic of the indigenous population of some African countries.     

基于稀疏表示变量选择方法的影像遗传学数据分析

目的:采用影像遗传学研究方法探索精神分裂症的影像遗传学特征。方法:在传统稀疏回归模型的基础上，改进 了其在不同范数条件下进行变量选择的能力，形成一种基于稀疏表示变量选择算法，并将该算法应用于208 个受试者的 41 236个功能磁共振成像数据和722 177个单核苷酸多态性数据的综合分析。通过对两类数据施加不同的权重因子，并 使用不同的Lp （p=0、0.5、1）范数分别对模型进行求解，筛选出两类数据在不同条件下的显著特征。结果:基因DAOA和 HTR2A在3种范数下均被筛选出。此外，在影像学数据方面，发现中央前回、枕上回、顶下缘角回、角回、内侧和旁扣带脑 回、后扣带回脑区与精神分裂症相关，此发现与先前精神分裂症的临床医学研究结果一致。结论:基于稀疏表示变量选择 方法应用于影像遗传学数据分析是一个有效可行的途径，为今后精神分裂症的影像遗传学研究提供了一种新的研究 思路。     

中国胰岛素依赖性糖尿病病人（HLA－DR9）的HLA－DQB1基因顺序分析

用血清学方法研究显示中国人胰岛素依赖性糖尿病（ＩＤＤＭ）与ＨＬＡ－ＤＲ９相关。鉴于白种人中的研究显示ＩＤＤＭ与ＨＬＡ－ＤＱβ链第５７位氨基酸相关，Ａｓｐ－５７对ＩＤＤＭ呈抗性，ｎｏｎ－Ａｓｐ与ＩＤＤＭ易感性相关。我们用ＰＣＲ技术扩增了中国人中血清学ＤＲ９纯合的ＩＤＤＭ患者和正常对照的ＨＬＡ－ＤＱＢ１基因第二外显子并测定了核苷酸顺序，结果未发现ＩＤＤＭ特异ＨＬＡ－ＤＱＢ１等位基因，但发现ＩＤＤＭ病人ＨＬＡ－ＤＱＢ１５７位均为天冬氨酸。表明中国ＩＤＤＭ患者中的ＨＬＡ－ＤＱＢ１５７位天冬氨酸不一定具有保护个体抵抗ＩＤＤＭ的足够能力。ＩＤＤＭ易感性可能涉及多个基因位点的变化，另外还可能与其它遗传因素及环境因素有关。     

The DQA1*0104 allele is carried by DRB1*1001- and DRB1*1401-positive haplotypes in Caucasians, Africans and Orientals

Abstract: The DQA1*0104 allele is known to differ from DQA1*0101 by a single nucleotide in the sequenced part of the first exon. DQA1*0104 has a guanine in the second position of the second expressed codon, whereas DQA1*0101 and all other sequenced DQA1 alleles have an adenine in that position, changing aspartic acid to glycine. The DQA1*0104 allele was originally described in African Americans with the DRB1*12, DRB3*0101, DQA1*0104, DQB1*0501, DRB1*12, DRB3*0202, DQA1*0104, DQB1*0605 or DRB1*14, DQA1*0104, DQB1*0503 haplotypes. When developing DQA1 typing by PCR amplification with sequence-specific primers (PCR-SSP), we observed that all DR10- and DR14-positive samples carried the DQA1*0104 allele, wheres all DRB1*01 -positive DNAs carried the closely related DQA1*0101 allele. In the present study, samples representing the major ethnic groups with DR-DQ haplotypes known to carry the DQA1*0104 allele or the very similar DQA1*0101 allele were investigated by Taq I RFLP analysis, PCR-SSP typing and nucleotide sequencing. The DQA1*0104 allele was found to differ from DQA1*0101 not only in the second expressed codon, but also by a productive mutation in the signal peptide. All investigated DRB1*1001 -(n = 24) and DRB1*1401 -positive (n = 25) haplotypes, defined by homozygosity or association, of Caucasian, African or Oriental origin carried the DQA1*0104 allele, whereas the DQA1*0101 allele was found on all DRB1*01 -positive (n = 32) haplotypes. These findings demonstrate that in the assignment of HLA class II alleles, polymorphism outside the second exon sometimes must be considered. The maintenance of the DQA1*0104 allele on a few distinct haplotypes indicates that the allele is old and might also be compatible with a functional difference between the DQA1*0101 and DQA1*0104 alleles.