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According to the WHO, 16-18 million people in Central and South America are infected by Trypanosoma cruzi. Chagasic achalasia affects between 7.1% and 10.6% of the population. The aim of this study was to evaluate the effects of Botox injections in the clinical response and esophageal function of patients with dysphagia due to chagasic achalasia. In total, 24 symptomatic patients with chagasic achalasia were randomly chosen to receive Botulinum Toxin (BT) or saline injected by endoscopy in the lower esophageal sphincter (LES). Patients were monitored with a clinical score of dysphagia and an objective assessment (esophagograms, scintillography, manometry, and nutritional assessment) for a period of 6 months. Clinical improvement of dysphagia was statistically significant (P < 0.001) in patients receiving BT when compared with the placebo. There was no significant difference in the placebo group regarding clinical score, LES basal pressure and esophageal emptying time. Esophageal emptying time in the toxin group was significantly lower than in the placebo (P=0.04) after 90 days. There were non-significant increases in esophageal emptying of 25.36% and 17.39%, respectively, at 90 and 180 days, in the BT group (P=0.266). Gender, age, and baseline LES pressure did not influence the response to BT. Our data strongly suggests that intrasphincteric injection of BT in LES is clinically effective in the treatment of chagasic achalasia.  相似文献   
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OBJECTIVE: The pathogenesis of nonalcoholic fatty liver disease (NAFLD) is multifactorial, and the presence of insulin resistance is recognized as the pathophysiological hallmark of this condition. Arterial hypertension is referred as an insulin-resistant state, and insulin resistance may substantially contribute to the cardiovascular risk in this disorder. We examined the inter-relationship between insulin sensitivity, adiponectin levels, and NAFLD in hypertensive patients with different circadian blood pressure profiles. METHODS: Eighty never-treated patients with essential hypertension were selected for having a nocturnal decrement of blood pressure that was at least 10% (dippers, n=47) or less than 10% (nondippers, n=33) of daytime values. No patient had diabetes mellitus, obesity, hyperlipidemia, or other risk factors for hepatic disease. The two groups were similar as to sex, age, and BMI. Abdominal fat distribution and NAFLD were assessed by ultrasonography. RESULTS: Hepatic steatosis was detected in 57.5% of all patients. Nondippers showed a higher prevalence of NAFLD than dippers (81.8 vs. 40.4%, P<0.005). Insulin and the homeostasis model of assessment index were higher (P<0.001) and adiponectin was lower (P<0.001) in nondippers than in dippers, whereas no difference was found in regional fat, liver enzymes, and other metabolic parameters. At multivariate analysis, factors independently associated with nondipping were insulin (P<0.05) and adiponectin (P<0.01) with the homeostasis model of assessment index being of borderline significance. CONCLUSION: In the absence of major risk factors for the development of NAFLD, a high prevalence of liver steatosis was associated with insulin resistance and low adiponectin levels in essential hypertensive patients with a nondipping profile.  相似文献   
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Several stimuli are able to alter the synthesis of cardiac myosin isoenzymes. Particularly in the rat a shift toward a low-ATPase isomyosin is generally observed during development and in cardiac hypertrophy due to pressure overload. On the contrary in spontaneously hypertensive turkeys both ageing and the increasing degree of cardiac hypertrophy are accompanied by a different behaviour of ventricular myosin. In fact in a previous study we have shown that the Ca2+-activated ATPase activity of ventricular myosin increases about three folds from young normotensive to old hypertensive animals. Accordingly the peptide pattern obtained after chymotryptic digestion of myosin showed that some peptides, which are not evident or barely discernible in young animals, are present in the adult ones. In this study we compare the ventricular myosin from young normotensive and adult hypertensive turkeys with atrial myosin. The results obtained suggest that in the ventricles of hypertensive turkeys the synthesis of an isomyosin with biochemical properties close to those of atrial myosin occurs.  相似文献   
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Summary We studied subunit composition and Ca++-activated ATPase activity of myosin isolated from atria and ventricles of hearts explanted from patients suffering from idiopathic dilated cardiomyopathy. At variance with previously published data, we have been unable to detect in the ventricular subendocardial layers a significant amount of myosin atrial-like light chain 1 (ALC1), which has been reported to be related to some hemodynamic features of the hypertrophied and failing heart. Such a subunit was not visible in the septum and in the subepicardial layers either. On the contrary, in both atria a ventricular-like light chain 2 (VLC2) was found. The nature of this additional light chain was confirmed on the basis of two-dimensional electrophoresis and immunoblotting techniques with polyclonal antibodies reacting with VLC2. In these patients we also observed a depressed Ca++-activated ATPase activity, both in atrial and ventricular myosin. The explanation for this finding in ventricles still remains obscure since neither myosin light chains, nor myosin heavy chains showed any difference between patients with dilated cardiomyopathy and controls. On the contrary, in atria we clearly identified changes consistent with the expression of myosin heavy chains of ventricular type and VLC2, which can account for the depressed Ca++-activated ATPase activity.  相似文献   
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BACKGROUND: Pancreatic cancer and cholangiocarcinoma are the main causes of malignant biliary stricture. Both types of cancers have dismal survival rates, and treatment has little or no effect on prolonging the patients lives. Prognostic definition at initial endoscopic retrograde cholangiopancreatography is important to choose the most suitable management. AIM: To analyse endoscopic brushing and bilirubinemia importance in determination of the survival of patients with malignant biliary stricture. METHODS: Patients with biliary strictures diagnosed during endoscopic retrograde cholangiopancreatography were submitted to double brushing cytology. Serum samples were taken from all patients for bilirubinemia assay. Patients were followed to determine the final diagnosis and survival rates. RESULTS: A total of 50 patients with biliary stricture underwent endoscopic retrograde cholangiopancreatography (40 ultimately found to have a final diagnosis of malignant disease). Hyperbilirubinemia or cytology brushing positive for malignancy was related to a shorter survival rate. CONCLUSION: This research data demonstrate the possibility of determining the prognosis of patients with malignant biliary stricture using endoscopic brushing results and bilirubinemia levels.  相似文献   
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Summary Chronic pressure overload induces a redistribution in myosin isoenzymes as demonstrated by Ca++-activated ATPase activity, electrophoresis under non-denaturing conditions and immunohistochemistry.We compared, in two groups of renal hypertensive rats and control rats, the isoenzymic patterns obtained by electrophoresis under non-denaturing conditions with those observed after heavy chains digestion with S. Aureus V8 protease.In the hypertensive animals in which a shift towards the slow V2 and V3 isomyosins was evident, peptide mapping always gave origin to a band which was not present in the controls.Since we consider this peptide as a marker of the redistribution towards the slow isoforms, peptide mapping according to Cleveland appears to be a simple and useful method to assess differences in isomyosin composition, at least between hypertrophic pressure-overloaded and normal rat ventricles. Moreover, in our experience this technique is simple, the patterns obtained from highly purified substrates are very reproducible and the digestion allows easy and clear comparisons.  相似文献   
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