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BACKGROUND: The extent to which atrial fibrillation (AF) contributes to mortality in the Japanese general population has not been clarified. METHODS AND RESULTS: A randomly sampled general population from all over Japan (4,154 men, 5,329 women; age > or =30 years) was enrolled. Single electrocardiogram recordings were taken in the baseline survey. Stroke death, cardiovascular deaths and all-cause deaths during the subsequent 19 years were analyzed by the presence of AF at baseline. Cox's regression analysis was carried out to estimate the hazard ratios (HRs) of each cause of death attributable to AF after adjusting for other risk factors. Prevalence of AF was 0.64% in the study. The observed person-years were 162,980 among persons without AF and 699 among persons with AF. There were 1,919 deaths. Multivariate adjusted HRs for stroke death, cardiovascular death and all-cause death were 2.69, 2.76 and 1.88, respectively (p<0.05). These HRs were 14.7, 9.63 and 4.00 among persons aged 64 years or younger (p<0.05). CONCLUSION: AF affects stroke mortality, cardiovascular mortality and all-cause mortality in the Japanese general population. Careful attention should be paid to persons with AF in order to prevent future cardiovascular events.  相似文献   
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Background and methodsThere is controversy about the association between mild-to-moderate alcohol consumption and a reduced risk of cardiovascular diseases. The relationships between daily alcohol consumption and the incidence of acute myocardial infarction (MI) or ischemic stroke (IS) were examined in men in a community-based, prospective cohort study (n = 8014, age 40–80 years, mean age = 64.1 years). Alcohol consumption was categorized into 3 groups (A1, none or occasional; A2, ≤25 g/day; A3, >25 g/day as ethanol) at baseline.ResultsDuring the mean follow-up of 5.5 years, 53 MIs and 186 ISs occurred. On Cox regression analysis adjusted for age, hypertension, diabetes, dyslipidemia, smoking index, and body mass index (BMI), the hazard ratio (HR) for incident MI was significantly lower in the A2 group than in the A1 group (HR = 0.49, p = 0.043). The HR for incident MI in the A3 group tended to be lower than in the A1 group (HR = 0.53, p = 0.10). In obese subjects, while a significantly lower HR for incident MI in the A2 group was retained (HR = 0.29, p = 0.049), no significant difference in the HR of the A3 group compared with the A1 group was found. No significant differences were found in the IS-free curve among the 3 groups of alcohol consumption.ConclusionsAlcohol consumption may have a protective effect on the onset of MI but not on IS in the general population. A U-shaped relation between alcohol consumption and incident MI was found in obese subjects. An appropriate limit for daily alcohol consumption, depending on the risk of ischemic heart disease, may need to be established.  相似文献   
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Leptin has been reported to exert an atherosclerotic effect by regulating expression of angiogenic factors that have been implicated in the pathogenesis of coronary artery disease (CAD). The purpose of this study was to investigate whether lipid-lowering therapy (LLT) with statins could affect leptin levels and angiogenic factors in patients with CAD. This study included 76 patients with CAD and 15 subjects without CAD (non-CAD). CAD patients were randomized to 6?months of intensive LLT with atorvastatin or moderate LLT with pravastatin. Plasma leptin, angiopoetin-2 (Ang-2), hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) levels were measured prior to statin therapy (baseline) and after 6?months. Baseline levels of leptin, Ang-2, HGF and VEGF were higher in the CAD group than in the non-CAD group (all P?<?0.05). Treatment with intensive LLT decreased leptin, Ang-2, HGF and VEGF levels, whereas moderate LLT did not change these levels. This study suggests that LLT with atorvastatin decreases leptin levels and angiogenic factors in patients with CAD, possibly contributing to the beneficial effects of LLT with atorvastatin in CAD.  相似文献   
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Diabetes mellitus (DM) is a strong risk factor for cardiovascular (CV) disease. Plasma B-type natriuretic peptide (BNP) levels are elevated in various types of cardiac diseases. Increased plasma BNP levels have been reported to be associated with CV risk in apparently healthy individuals. However, no studies have yet examined the specific value of plasma BNP for predicting CV incidence in unselected DM subjects in a community-based population.In a community-based DM cohort (n = 1,059, mean = 66 years), baseline BNP levels were determined, and CV events were followed and captured prospectively. The cohort was divided by plasma BNP quintiles. The Cox proportional hazard model was used to determine the relative hazard ratios (HR) among the quintiles. In addition, the effects of adding the plasma BNP or urine albumin-to-creatinine ratio (UACR) to an established CV risk scoring model was examined by calculating the area under the receiver operating characteristic (ROC) curve (AUC).During the 5.7 year follow-up period, CV events were identified in 65 of the DM cohort. There was a significant association between plasma BNP levels and CV event rate (P < 0.001). HR was significantly increased in the highest quintile compared to the lowest (HR = 4.38; 95%CI 1.69 -11.84). The AUC generated from ROC analysis of the Framingham risk score for predicting general CV events was improved by adding BNP testing (from 0.66 to 0.74; P = 0.05), but not by adding UACR (from 0.66 to 0.67; P = 0.49).In a community sample of people with DM, plasma BNP levels above the 80 percentile are directly associated with CV risk, and measurement of plasma BNP alone or in conjunction with an established CV risk score is of value in predicting CV events in these subjects.  相似文献   
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Purpose

β3-Adrenergic receptor (ADRB3) Trp64Arg polymorphism is associated with atherogenic risk factors that include weight gain, insulin resistance, and diabetes. Habitual exercise brings higher cardiorespiratory fitness and results in the amelioration of atherosclerotic risk factors. However, the effects of cardiorespiratory fitness level and ADRB3 Trp64Arg polymorphism on the risk of cardiovascular disease remain unclear. A cross-sectional investigation of 877 Japanese men and women (18–75 years old) was performed to clarify the effects of cardiorespiratory fitness on the relationship between ADRB3 Trp64Arg polymorphism and risk of cardiovascular disease.

Method

Common carotid intima-media thickness (ccIMT) and blood lipid profiles were assessed as surrogate markers of atherosclerosis. We measured peak oxygen uptake ( \(\dot V\) O2peak) during incremental cycle ergometer exercise testing. Subjects were divided into groups with high (High-Fit) and low (Low-Fit) levels of cardiorespiratory fitness based on the median value of \(\dot V\) O2peak for sex and decade.

Results

Levels of body fat, triglycerides, and plasma glucose were lower and high-density lipoprotein cholesterol levels and \(\dot V\) O2peak were higher in High-Fit subjects than Low-Fit subjects. ADRB3 Trp64Arg polymorphism did not significantly affect ccIMT or blood lipid profiles. In Low-Fit subjects, ccIMT was higher in individuals with the Arg/Arg genotype compared to the Trp/Trp and Trp/Arg genotypes (each P < 0.0001); however, ADRB3 polymorphism had no effect in High-Fit subjects.

Conclusion

Higher levels of cardiorespiratory fitness may attenuate the risk of atherosclerosis associated with ADRB3 Trp64Arg polymorphism.  相似文献   
19.
BACKGROUND/AIMS: We previously developed a multi-step, incremental expansion method (multi-step method) for radio frequency ablation (RFA) in vitro, which prevented increases in pressure and reduced the ablation time as compared with other methods. In this study, we evaluated liver parenchymal pressure and portal endothelium damage during RFA with different devices and protocols in an in vivo porcine model. METHOD: Nine healthy female pigs were anaesthetized. RFA was performed with two different devices and protocols; one involved the use of a LeVeen needle with a single-step full expansion method or a multi-step method, and the other used a cool-tip needle with 40 or 60 W power. We measured the pressure in the liver parenchyma and the gallbladder during RFA. We also evaluated portal endothelium damage by NADH staining. RESULTS: The multi-step method with the LeVeen electrode resulted in the lowest parenchymal and intra-gallbladder pressures (multi-step method相似文献   
20.
MR imaging of primary malignant lymphoma of the pancreas   总被引:2,自引:0,他引:2  
Pancreatic lymphoma is rare and is usually found as a large pancreatic mass. We report the case of a small 2-cm pancreatic lymphoma in a 54-year-old woman that had its histological origin in the pancreatic parenchyma. The mass showed homogeneously high signal-intensity on T2-weighted images and low signal-intensity on T1-weighted images. The infiltrative nature and hypovascularity in early-phase dynamic contrast study without encasement of arteries and veins were well demonstrated by MR imaging and were consistent with malignant lymphoma.  相似文献   
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