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Wai CT Fontana RJ Polson J Hussain M Shakil AO Han SH Davern TJ Lee WM Lok AS;US Acute Liver Failure Study Group 《Journal of viral hepatitis》2005,12(2):192-198
The role of hepatitis B virus (HBV) genotypes in the outcome of acute HBV infection is unclear. In this study, we aimed to evaluate the clinical and virological features of patients with hepatitis B-related acute liver failure (HBV-ALF) in the US. Clinical and laboratory features of consecutive patients with HBV-ALF from the US ALF Study Group were analysed. Prevalence of HBV genotypes, precore stop (G1896A) and core promoter dual (T1762A, A1764T) variants among patients with HBV-ALF were compared with a cohort of 530 patients with chronic HBV infection. Thirty-four HBV-ALF patients were studied: mean age 41 years, 56% men, 25 had detectable HBV-DNA. HBV genotypes A, B, C and D were found in 36, 24, 8 and 32% patients, respectively. Precore stop and core promoter dual variants were detected in 32 and 44% of patients, respectively. Twenty-three (68%) patients survived: 14 after liver transplant, nine without transplant. Older age was the only independent factor associated with poor outcome. Compared with patients with chronic HBV infection, patients with ALF were more likely to be non-Asians (88% vs 44%, P = 0.005) and to have genotype D (32% vs 10%, P < 0.01). A higher prevalence of HBV genotype D persisted even after matching for race and HBeAg status (32% vs 16%, P = 0.007). We concluded that HBV genotype D was more frequently found in patients with HBV-ALF than those with chronic HBV infection in the US. Further studies are needed to determine if HBV genotypes play a role in the outcome of acute HBV infection. 相似文献
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Influence of apolipoprotein A-1 promoter polymorphism on lipid levels and responses to dietary change in Finnish adults 总被引:2,自引:0,他引:2
QING-HE MENG P. PAJUKANTA L. VALSTA A. ARO P. PIETINEN & M. J. TIKKANEN 《Journal of internal medicine》1997,241(5):373-378
Objectives. To analyse the association between the G/A polymorphism in the apolipoprotein A-1 (apo A-1) promoter region and plasma lipid levels, as well as their responses to dietary change, in Finnish adults.
Subjects and design. Blood samples from 86 subjects (42 men, 44 women) who attended a dietary intervention study carried out in North Karelia in 1993 were available for the current analysis. The diet study consisted of a 2-week baseline period, followed by an 8-week intervention period, and an 8-week switchback period.
Intervention. Diet was modified to a low-fat, low-cholesterol diet during the dietary intervention.
Main outcome measures. Fasting plasma lipid, lipoprotein and apolipoprotein levels were determined.
Results. At baseline, the high-density lipoprotein (HDL) cholesterol and apo A-1 levels were higher ( P <0.01) and the triglyceride levels were lower ( P <0.05) in men, but not in women, with the A allele. The differences in HDL cholesterol and apo A-1 levels between genotypes remained during the low-fat, low-cholesterol diet and switchback periods. Apart from the difference between responses in apo A-1 during switchback to the original diet, lipid responses to dietary change did not differ significantly between genotypes.
Conclusion. Our findings indicate a significant association between the apo A-1 promoter polymorphism and plasma apo A-1 and HDL-cholesterol in men. In theory, the higher plasma HDL-cholesterol and apo A-1 levels in the GA/AA group may confer some protection against coronary artery disease. The differences in HDL-cholesterol and apo A-1 levels between genotypes persisted during different diets suggesting that the possible benefit is independent of fat and cholesterol intake. 相似文献
Subjects and design. Blood samples from 86 subjects (42 men, 44 women) who attended a dietary intervention study carried out in North Karelia in 1993 were available for the current analysis. The diet study consisted of a 2-week baseline period, followed by an 8-week intervention period, and an 8-week switchback period.
Intervention. Diet was modified to a low-fat, low-cholesterol diet during the dietary intervention.
Main outcome measures. Fasting plasma lipid, lipoprotein and apolipoprotein levels were determined.
Results. At baseline, the high-density lipoprotein (HDL) cholesterol and apo A-1 levels were higher ( P <0.01) and the triglyceride levels were lower ( P <0.05) in men, but not in women, with the A allele. The differences in HDL cholesterol and apo A-1 levels between genotypes remained during the low-fat, low-cholesterol diet and switchback periods. Apart from the difference between responses in apo A-1 during switchback to the original diet, lipid responses to dietary change did not differ significantly between genotypes.
Conclusion. Our findings indicate a significant association between the apo A-1 promoter polymorphism and plasma apo A-1 and HDL-cholesterol in men. In theory, the higher plasma HDL-cholesterol and apo A-1 levels in the GA/AA group may confer some protection against coronary artery disease. The differences in HDL-cholesterol and apo A-1 levels between genotypes persisted during different diets suggesting that the possible benefit is independent of fat and cholesterol intake. 相似文献
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Promoter hypermethylation of CDKN2A,MGMT, MLH1, and DAPK genes in laryngeal squamous cell carcinoma and their associations with clinical profiles of the patients 下载免费PDF全文
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目的:分析并鉴定STGC3基因转录调控元件,探讨鼻咽癌STGC3基因的转录调控分子机制。方法:运用
生物信息学,预测并分析STGC3基因核心启动子区的转录因子结合位点;将相关转录因子结合位点,制备3 种探
针即生物素标记野生型、突变型及未标记野生型;提取CNE2细胞核蛋白,利用电泳迁移率变动分析( EMSA)
及染色质免疫共沉淀( ChIP)分析,体内外鉴定转录因子结合位点。结果:在STGC3基因核心启动子区存在21
个转录因子结合位点,其中9 个为Sp1 转录因子结合位点;进一步严格限定参数,STGC3基因核心启动子区域含
有转录因子结合位点5 个,其中Sp1 转录因子结合位点2 个;EMSA和ChIP 实验结果显示,STGC3基因中存在转
录因子Sp1 特异性结合位点,从而鉴定出STGC3基因转录调控元件。结论: STGC3基因核心启动子区含有Sp1
特异性结合位点,为该基因的转录调控元件。 相似文献
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