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Some patients with type B chronic active hepatitis have a high titer of hepatitis B virus DNA despite antibody against e antigen in the serum. Clones of hepatitis B virus were propagated from the sera of seven patients with this disease, and the precore region was sequenced. Essentially all clones (128/131 or 98%) showed a point mutation from guanine to adenine at nucleotide 83, converting codon 28 for tryptophan (TGG) to a stop codon (TAG); the second guanine-to-adenine point mutation at nucleotide 86 was identified in only 29 clones from two patients. In patients followed up since they had hepatitis B e antigen, a shift from guanine to adenine was observed at nucleotide 83 along with the seroconversion to the antibody to e antigen. The precore-region product is required for the synthesis and secretion of e antigen from hepatocytes. A point mutation from guanine to adenine at nucleotide 83 observed in the seven patients, therefore, would be responsible for disturbed secretion of e antigen.  相似文献   
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In mammals, both circadian rhythm and aging play important roles in regulating time-dependent homeostasis. We previously discovered an age-related increase element binding protein, hnRNP A3, which binds to the 3′-untranslated region (UTR) of blood coagulation factor IX (FIX). Here, we describe other members of this protein family, hnRNP C and hnRNP H, which bind to the 3′-UTR of the mouse circadian clock gene Period 2 (mPer2). RNA electrophoretic mobility shift assays using a 32P-labeled Per2 RNA probe coupled with two-dimensional gel electrophoresis followed by MALDI-TOF/MS peptide mass fingerprint analysis was used to analyze these proteins. Western blotting suggested that the total expression of these proteins in mouse liver cell nuclei does not increase with age. Two-dimensional gel electrophoresis analysis of age-related protein expression showed that many isoforms of these proteins exist in the liver and that each protein exhibits a complex age-related expression pattern. These results suggest that many isoforms of proteins are regulated by different aging systems and that many age regulation systems function in the liver.  相似文献   
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ObjectiveTo investigate the relationship between TXNIP polymorphisms, diabetes and hypertension phenotypes in the Brazilian general population.MethodsFive hundred seventy-six individuals randomly selected from the general urban population according to the MONICA-WHO project guidelines were phenotyped for cardiovascular risk factors. A second, independent, sample composed of 487 family-trios from a different site was also selected. Nine TXNIP polymorphisms were studied. The potential association between TXNIP variability and glucose-phenotypes in children was also explored. TXNIP expression was quantified by real-time PCR in 53 samples from human smooth muscle cells primary culture.ResultsTXNIP rs7211 and rs7212 polymorphisms were significantly associated with glucose and blood pressure related phenotypes. In multivariate logistic regression models the studied markers remained associated with diabetes even after adjustment for covariates. TXNIP rs7211 T/rs7212 G haplotype (present in approximately 17% of individuals) was significantly associated to diabetes in both samples. In children, the TXNIP rs7211 T/rs7212 G haplotype was associated with fasting insulin concentrations. Finally, cells harboring TXNIP rs7212 G allele presented higher TXNIP expression levels compared with carriers of TXNIP rs7212 CC genotype (p = 0.02).ConclusionCarriers of TXNIP genetic variants presented higher TXNIP expression, early signs of glucose homeostasis derangement and increased susceptibility to chronic metabolic conditions such as diabetes and hypertension. Our data suggest that genetic variation in the TXNIP gene may act as a “common ground” modulator of both traits: diabetes and hypertension.  相似文献   
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There are limited clinical trials examining the efficacy of antihypertensive drug combinations aimed at preventing cardiovascular events. Therefore, we designed a randomized controlled trial using amlodipine as the base drug of a multi-drug regimen, the Optimal Combination of Effective ANtihypertensives (OCEAN) Study, to determine the drug combination that is most efficacious in the prevention of cardiovascular events, such as stroke. The OCEAN Study is a collaborative study between Japan and China, enrolling 20?000 patients and following them for 3 to 4 years. A pilot study was conducted before the full-scale study to confirm the feasibility of the protocol and that the study groups and infrastructures could function properly. A total of 279 Japanese patients were enrolled from 57 participating medical institutions between June and December 2004. Two hundred and sixty-six patients (mean age: 65.9 years) were treated with amlodipine alone. One hundred and fifty-four of these patients (57.9%) did not reach the treatment targets (<140/90?mm?Hg for the elderly and patients with cerebrovascular disease, <130/80?mm?Hg for those with diabetes mellitus, chronic kidney disease or prior myocardial infarction) and a second agent was added. They were randomly allocated into three different treatment groups using a diuretic, a β-blocker or an angiotensin-converting enzyme inhibitor/angiotensin II receptor antagonist. The pilot study showed that the protocol was appropriate, and the inclusion of patients with slightly higher blood pressures was necessary to increase the randomization rate. It also confirmed that we organized properly functioning study groups and infrastructures.  相似文献   
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