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To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility.  相似文献   
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AIM: To explore the effect of acamprosate and naltrexone on craving and alcohol consumption in the treatment of alcohol dependence. DESIGN: A randomized, double-blind, single-dummy, placebo-controlled trial. SETTING: Three treatment centres in Sydney, Australia. PARTICIPANTS: A total of 169 alcohol-dependent subjects were given naltrexone (50 mg/day), acamprosate (1998 mg/day) or placebo for 12 weeks, in conjunction with manualized medication compliance therapy. INTERVENTION: During the course of the trial, participants kept a daily diary which included the number of standard drinks they consumed and their peak craving for alcohol that day rated on a 0-10 scale. MEASUREMENTS: Subjective ratings of daily craving and daily drinking for the first 6 weeks of treatment. FINDINGS: Mixed/hierarchical linear models were employed on an intention-to-treat basis. Analyses revealed that craving was a significant predictor of daily drinking and baseline levels of depression were the best predictor of daily craving. There was no significant improvement in model fit when treatment group was added both in models of daily craving and daily drinking. Daily alcohol consumption was best predicted by a model incorporating baseline dependence and depression scores, and daily craving, entered as a time-varying covariate. However, there was a significant craving x time x treatment interaction (t = -3.365, df = 4413.712, P < 0.001), suggesting that at higher levels of craving drinking was reduced at a significantly greater rate with naltrexone compared to acamprosate. CONCLUSIONS: Naltrexone had a greater effect on drinking when craving was high. These results support the role of naltrexone in reducing craving when that craving is highly salient. The role of acamprosate in reducing craving was not supported by these findings.  相似文献   
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BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8)  相似文献   
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BackgroundElevated levels of total plasma homocysteine are a risk factor for atherosclerotic disease.AimsThe rationale behind this study is to explore the correlation between degree and site of coronary lesion and hyperhomocysteinemia in Lebanese CAD patients and assess environmental and genetic factors for elevated levels of total plasma homocysteine.MethodsA total of 2644 patients were analyzed for traditional CAD risk factors. Logistic regression was performed to determine the association of hyperhomocysteinemia with degree and site of coronary lesions controlling for risk factors. Environmental and genetic factors for hyperhomocysteinemia were analyzed by logistic regression using a candidate gene approach.ResultsTraditional risk factors were correlated with stenosis. Hyperhomocysteinemia associated with increased risk of overall stenosis, and risk of mild and severe occlusion in major arteries. Hyperhomocysteinemia and hypertension were highly correlated suggesting that hyperhomocysteinemia acts as a hypertensive agent leading to CAD. Diuretics and genetic polymorphisms in MTHFR and SLCO1B1 were associated with hyperhomocysteinemia.ConclusionsHyperhomocysteinemia is a medical indicator of specific vessel stenosis in the Lebanese population. Hypertension is a major link between hyperhomocysteinemia and CAD occurrence. Genetic polymorphisms and diuretics’ intake explain partly elevated homocysteine levels. This study has important implications in CAD risk prediction.  相似文献   
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Weight loss and changes in growth are noted in children treated with interferon alpha (IFN-α). The aim of this study was to prospectively determine changes in weight, height, body mass index (BMI), and body composition during and after treatment of children with hepatitis C virus (HCV). Children treated with pegylated interferon alpha-2a (Peg-IFN-α2a) ± ribavirin in the Pediatric Study of Hepatitis C (PEDS-C) trial underwent anthropometric measurements, dual-energy X-ray absorptiometry scan, as well as dietary and activity assessments during and after treatment. One hundred and fourteen (55% male) children, with a mean age of 11 ± 3 years, were randomized, and 107 received treatment for at least 24 weeks. Subjects were divided into three groups according to duration of treatment: 24 (N = 14), 48 (N = 82), or 72 (N = 11) weeks. Decrements of up to 0.50 z score were observed for weight, height, and BMI while on therapy among all groups (P ≤ 0.01, compared to baseline). In the group treated for 48 weeks, 29 (33%) subjects had greater than 0.5-unit decrement in height-for-age z (HAZ) score. Though weight-for-age and BMI z scores returned to baseline after cessation of therapy, mean HAZ score was slower to rebound, still lower than baseline at 96 weeks post-therapy for the long-treatment duration group (P = 0.03) and lower than baseline in most children treated for 48 weeks. Percent body fat, fat-free mass z scores, and triceps skinfold z scores decreased with therapy. Dietary energy intake and levels of physical activity did not change during treatment. CONCLUSIONS: Peg-IFN-α2a was associated with significant changes in body weight, linear growth, BMI, and body composition in children. These effects were generally reversible with cessation of therapy, although HAZ scores had not returned to baseline after 2 years of observation in many. Longer term growth data are needed among children treated for chronic HCV.  相似文献   
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