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101.
从日本血吸虫大陆株成虫分离总RNA,逆转录合成cDNA第一链,根据菲律宾株26kDa谷胱甘肽S-转移酶(GST)的cDNA序列,设计并合成引物,扩增出26kDa的编码区基因,并克隆到pBluescript质粒。初步酶切鉴定后,从两端对插入片段进行核苷酸序列测定。结果与菲律宾株比较,核苷酸同源性为99.8%,仅第582位碱基不同,菲律宾株为A,而大陆株为G。比较从cDNA推导出的氨基酸序列,两者100%相同。测序结果也与曼氏血吸虫进行了比较。 相似文献
102.
Heritability and Expression of C-Reactive Protein in Type 2 Diabetes in the Diabetes Heart Study 总被引:1,自引:0,他引:1
Leslie A. Lange Kathryn Burdon † Carl D. Langefeld Yongmei Liu Stephanie R. Beck Stephen S. Rich Barry I. Freedman K. Bridget Brosnihan David M. Herrington Lynne E. Wagenknecht Donald W. Bowden 《Annals of human genetics》2006,70(6):717-725
Elevated C-reactive protein (CRP) levels are associated with both prevalent and incident cardiovascular disease. In this study, familial aggregation was estimated, and we tested for association between serum CRP levels and polymorphisms within the CRP and APOE genes in sib-ships with type 2 diabetes mellitus, a population at increased risk for cardiovascular disease. CRP levels were determined in 461 diabetes-affected subjects from 224 sibships from the Diabetes Heart Study (DHS). Heritability estimates of CRP levels were obtained using variance component models. Genetic influence on serum CRP levels by single nucleotide polymorphisms (SNPs) in the CRP and APOE genes was evaluated by association analysis using mixed models. Subjects were Caucasian American (84%) and African-American (16%), 53% female, and had an average age of 62.2 ± 9.2 years. The median CRP level was 3.3 mg/L (range 0 to 59.3 mg/L), and estimated heritability for CRP was approximately 40%. Estimates of heritability were significantly greater than zero (P < 0.0001) and relatively constant, despite adjustments for important modifiers (age, sex, ethnicity, diabetes duration, statin-use and anti-inflammatory use) of CRP. There was no significant evidence for association of CRP levels with CRP gene SNPs; however, consistent with previous reports, there was significant evidence of association of CRP levels with polymorphisms within the APOE gene. These data indicate CRP levels are significantly influenced by genetic (and/or environmental) factors that are shared within DHS families. While the APOE locus shows evidence of contributing to CRP levels, no evidence of CRP gene polymorphism association with CRP levels was observed. 相似文献
103.
The novel HLA-Cw*1802 allele is associated with B*5703 in the Bubi population from Equatorial Guinea
C. Vilches M. Bunce R. de Pablo M. E. Moreno S. Puente L. Sanz M. Kreisler 《Tissue antigens》1997,49(6):644-648
The HLA-Cw*1801 specificity, a Cw7/Cw4 hybrid allele, has recently been described in association with B*8101 (formerly B"DT"). In this study, the new Cw*1802 variant, differing from Cw*1801 at exon 5. is found associated with B*5703 in Bubi individuals from Equatorial Guinea. Confirmatory complete coding regions of B*5703 and B*3910 are also reported. 相似文献
104.
The identification of the new allele HLA-A*6813, which was found in a woman of Syrian origin and her son, is described. In the sequence analysis the new allele differs from A*68011 by positions 259 (A>G) and 261 (C>G) in exon 2. As the structure is thus identical to the HLA-A consensus sequence it is likely that the new allele originated by gene conversion. At the protein level, the new allele has one amino acid difference from A*6801 (Asn63Glu), which results in a distinct banding pattern in one dimensional-isoelectric focusing. Amino acid residue 63 contributes to the formation of pocket A and B and is thus important for peptide binding. A*6813 was serologically detectable only by two of six polyclonal, but by three monoclonal antisera. The restricted serological A68 activity may be explained by altered peptide binding as presented peptides can affect the serological recognition of major histocompatibility complex (MHC) class I molecules. Moreover, our findings suggest that a possible mismatch with the other known A*68 variants may impair clinical outcome of bone marrow transplantation. 相似文献
105.
Tobiasch E Kehm R Bahr U Tidona CA Jakob NJ Handermann M Darai G Giese M 《Virus genes》2001,22(2):187-199
Equine arteritis virus (EAV) is a member of the Arteriviridae family, that includes lactate dehydrogenase-elevating virus (LDV), porcine reproductive and respiratory syndrome virus (PRRSV), and simian haemorrhagic fever virus (SHFV). Equine arteritis is a contagious disease of horses and is spread via respiratory or reproductive tract. The objective of the present study is to evaluate the possibility for developing a model system for prevention horses against an EAV infection by DNA vaccination. A cDNA bank from the RNA of EAV was established. This gene library contains the translation unit of the EAV open reading frames (ORF) 1 to 7. The identity of the cDNA was confirmed by nucleotide sequence analysis. Using this defined EAV cDNA gene library the cDNA sequence of the viral ORFs were molecularly cloned into the corresponding sites of well characterized and powerful expression vectors (pCR3.1, pDisplay, and/or pcDNA3.1/HisC).The capability of these recombinant plasmids expressing the gene products of the individual viral ORFs 3 to 5, and 7 in induction of an immune response in mouse system was investigated. The Balb/c mice (ten mice per assay) were inoculated with the DNA of the constructed expression vectors harboring and expressing the EAV cDNA of the viral ORFs. The Balb/c mice were injected with about 100 g DNA diluted in 100 l PBS. The DNA was injected subcutaneously and into the tibialis cranialis muscle (Musculus gastrocnemius). The mice were boosted 3 to 5 times with the same quantities of DNA and under the same conditions at about two week intervals. Control mice received the same amount of parental expression vectors via an identical route and frequency.The pre- and post-vaccinated sera of the individual animals were screened by neutralization tests (NT). Neutralizing antibodies against EAV were detected when the animals were inoculated with the DNA of the expression vectors harboring cDNA of the EAV ORFs 5 and 7. Highest NT-titers were observed when the animals were administered with the cDNA of ORF 5 and/or with the cDNA of the neutralization determinants of EAV that is located on the N-terminal ectodomain of the gene product of ORF 5 between the amino acid positions 1–121. These results obtained from these studies justified proofing the capability of the EAV cDNA sequences of the viral genes including ORFs 5 and 7 in the autologous animal system horse. 相似文献
106.
Shichi D Kikkawa EF Ota M Katsuyama Y Kimura A Matsumori A Kulski JK Naruse TK Inoko H 《Tissue antigens》2005,66(3):200-208
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. 相似文献
107.
108.
Puri Beena Nelson William Porter Kevin R. Henchal Erik A. Hayes Curtis G. 《Virus genes》1998,17(1):85-88
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. 相似文献
109.
110.
Sugauchi F Orito E Kato H Suzuki S Kawakita S Sakamoto Y Fukushima K Akiba T Yoshihara N Ueda R Mizokami M 《Journal of medical virology》2003,69(1):33-40
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. 相似文献