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41.
Sympathetic activations may deteriorate myocardial failure due to progression of myocardial cell injury. In the present study, to test whether microtubules, calcium ion (Ca2+) sensitive cytoskeletons, are disrupted by norepinephrine (NE) and whether beta-adrenoceptor antagonist could attenuate the disruption of microtubules, structures of microtubules are studied in rat hearts with continuous subcutaneous infusions of norepinephrine. In the sham operated rats the microtubules stained by immunohistochemical technique showed normal network structures. A low dose of NE infusion (2 micrograms/kg/h) for 6 h resulted in a minimal change in microtubule structures. However, infusion for 24 h of NE (2 micrograms/kg/h) and a large dose of NE infusion (20 micrograms/kg/h) for 6h caused disruptions of microtubules in small patchy lesions (8 +/- 3%, 12 +/- 4% of area, respectively). A large dose of NE infusion for 24 h increased systolic blood pressure from 116 +/- 6 to 152 +/- 4 mmHg and increased plasma NE concentration from 430 +/- 40 to 17100 +/- 3700 pg/ml and further disrupted the network of microtubules in 40 +/- 6% of the total area. Propranolol (500 micrograms/kg/h) markedly attenuated NE-induced disruptions of microtubules. Disruptions of microtubules may be one of the underlying mechanism of deterioration of myocardial failure in chronic heart failure in which sympathetic activity is markedly activated.  相似文献   
42.
The genome of the hepatitis B virus contains a sequence (X gene) whose role is unclear. The almost complete region of the hepatitis B virus X gene was expressed in Escherichia coli, with the resulting protein being approximately 17 kilodaltons in molecular weight. Sera from 139 subjects were analyzed by Western blot analysis. Of the hepatitis B surface antigen-positive patients, anti-X was not found in 4 patients with acute hepatitis and in 12 healthy carriers, but was present in 41% (21/51) of the patients with chronic hepatitis, 63% (15/24) of those with liver cirrhosis, and 46% (12/26) of those with hepatocellular carcinoma. The expression of the X product in the liver tissues (43 hepatitis B surface antigen-positive patients) was investigated using an indirect immunohistochemical method. The X protein was observed in 64% (21/33) of the patients with chronic hepatitis and 50% (5/10) of those with liver cirrhosis, and was found when the serum was negative for anti-X. Hepatitis B core antigen was frequently expressed together with the X protein in the liver. The conclusions reached were that the frequency of anti-X increases with the length of chronic hepatitis B virus infection, that anti-X may suppress the expression of the X protein in the liver, and that the X protein may be related to hepatitis B virus replication.  相似文献   
43.
To clarify whether the formation of thrombi could be induced by atrial fibrillation itself or by factors predisposing to atrial fibrillation such as mitral stenosis, plasma D-dimer levels (cross-linked fibrin degradation products) were measured in 73 patients without atrial fibrillation (Group 2). In Group 1, 49 of the 73 patients had factors predisposing to atrial fibrillation such as valvular heart disease, and the remaining 24 had lone atrial fibrillation. In Group 2, 16 patients had organic heart disease and the remaining 5 had a chest pain syndrome. The plasma D-dimer level was significantly higher in Group 1 (150 +/- 19 ng/ml) than in Group 2 (61 +/- 3 ng/ml) (p less than 0.01, mean +/- standard error of the mean). In both groups, there were no significant differences in plasma D-dimer level between patients with and without organic heart disease (146 +/- 18 versus 156 +/- 46 ng/ml in Group 1; 61 +/- 4 versus 59 +/- 10 ng/ml in Group 2). These findings indicate that atrial fibrillation itself may be more important than factors predisposing to atrial fibrillation in the development of intracardiovascular clotting.  相似文献   
44.
Nishimori I  Miyaji E  Morimoto K  Nagao K  Kamada M  Onishi S 《Gut》2005,54(2):274-281
BACKGROUND AND AIMS: Serum antibodies to carbonic anhydrase (CA) II have been reported in patients with autoimmune pancreatitis (AIP) and Sjogren's syndrome (SjS). However, their significance in the pathogenesis of these diseases is controversial. The aim of this study was to identify serum antibodies to CA isozymes, which are expressed in ductal cells of the pancreas. METHODS: Recombinant proteins of human CAs IV, IX, and XII were obtained using a bacterial expression system, and five CA IV peptides with theoretically high antigenicity were synthesised. Western blotting and enzyme linked immunosorbent assay (ELISA) were used to detect serum antibodies to the CA isozymes. RESULTS: The first screening analysis by western blot showed serum antibodies to CA IV among three CA isozymes in patients with idiopathic chronic pancreatitis, including AIP patients. Further analysis by ELISA showed a significantly increased prevalence of serum antibodies to the truncated CA IV protein and the CA IV synthetic peptide (LGS LTT PTC DEK VVW TVF REP I) in patients with definite AIP (4/15 and 6/20, respectively; p<0.01), probable AIP (6/14 and 3/14; p<0.02), and SjS (9/20 and 8/40; p<0.001) compared with normal controls (0/26). There was no significant difference in the antibody prevalence rates between normal controls and patients with alcoholic chronic pancreatitis (2/15 in each) or pancreatic cancer (2/14 and 1/14, respectively). The presence of serum antibodies to the CA IV peptide showed significant correlations with serum gamma-globulin and IgG levels in AIP patients. CONCLUSIONS: These findings suggest that CA IV may be a target antigen that is commonly expressed in epithelial cells of specific tissues involved in AIP and its related diseases.  相似文献   
45.
Objective: In 2020, coronavirus disease-2019 (COVID-19) became the cause of a pandemic. In response, the Japan Sports Agency issued warnings about secondary damage to health, such as the threat to physical and mental well-being due to the lack of exercise in this situation. In this study, we report on cross-sectional and longitudinal examinations of standing trunk flexion to evaluate how temporary long-term school closures affected musculoskeletal function in elementary school students.Patients and Methods: All children in one public elementary school in T-city during the school years 2019 and 2020 were included in this study. A digital forward flexion meter was used to measure standing trunk flexion.Results: In this study, 284 (284/289: 98.3%) and 266 (266/274: 97.1%) children in school years 2020 and 2019, respectively, were found to have valid data for cross-sectional analysis. The standing trunk flexion did not show significant differences between grades or sexes. In the longitudinal analysis, the results of the comparison of standing trunk flexion in children for two consecutive years revealed significant differences only between grades 3 and 4 (P<0.05) and between girls in grades 3 and 4 (P<0.01), but no significant differences in other grades or among boys or girls were observed.Conclusion: Initially, we expected that there would be a difference in the results of functional assessment using standing trunk flexion depending on the period of absence from school. However, the results of this study showed no significant changes in standing trunk flexion. Moreover, since children’s musculoskeletal functions may be affected by various factors during the COVID-19 pandemic, they should be carefully monitored in the future.  相似文献   
46.
To test the hypothesis that 5'-nucleotidase activity during ischemia is attenuated by oxygen-derived free radicals, we measured ischemia-induced reactive hyperemic flow, adenosine release, and 5'-nucleotidase activity in dogs (n = 62). A 1-minute occlusion of the coronary artery caused reactive hyperemic flow (307 +/- 5 versus 92 +/- 1 ml.100 g-1.min-1 at baseline) with increased release of adenosine (14.4 +/- 1.4 versus 0.4 +/- 0.1 nmol.100 g-1.min-1 at baseline). Superoxide dismutase augmented (p less than 0.001) both peak coronary blood flow (333 +/- 6 ml.100 g-1.min-1) and repayment (436 +/- 12 versus 320 +/- 7 ml/100 g in the untreated group). Adenosine release during reperfusion was augmented (22.7 +/- 1.9 nmol.100 g-1.min-1, p less than 0.001), and 8-phenyltheophylline completely abolished the enhanced reactive hyperemia. Enzymatic assay of 5'-nucleotidase activity revealed that the administration of superoxide dismutase increases ecto-5'-nucleotidase activity in ischemic myocardium. When an inhibitor of ecto-5'-nucleotidase, alpha, beta-methyleneadenosine 5'-diphosphate, was administered, the effects of superoxide dismutase were completely abolished. Thus, we conclude that 1) the augmentation of reactive hyperemic flow caused by superoxide dismutase is attributed to the enhanced release of adenosine and 2) the enhanced release of adenosine over the untreated controls is attributed to the protection of ecto-5'-nucleotidase activity during ischemia.  相似文献   
47.
48.
The purpose of this study was to determine the differences in hepatic circulation and oxygen consumption in two groups: those with nonalcoholic obesity-related fatty live and those with alcoholic fatty liver. Although the histological degree of fatty infiltration was equal in the two groups, the delta Er569-650, as an index of the regional liver blood flow estimated by spectrophotometric method, was significantly lower in alcoholic fatty liver than in nonalcoholic fatty liver, and the in vivo hepatic oxygen consumption (VO2), also determined by hepatic reflectance spectrophotometry during peritoneoscopy, tended to be lower in alcoholic fatty liver than in nonalcoholic fatty liver. The oxygen saturation of hemoglobin in local liver blood (SO2) was, however, significantly higher in alcoholic fatty liver than in nonalcoholic fatty liver. These results suggest that an increase in oxygen extraction to maintain oxygen consumption, which was indicated by the lowering of the SO2, was not found in alcoholic fatty liver, in spite of a reduction of oxygen supply to the liver. It is concluded that the impairment of hepatic circulation and hepatic oxygen consumption was more serious in alcoholic fatty liver than in nonalcoholic fatty liver, possibly contributing to a different prognosis for the two forms of fatty liver.  相似文献   
49.
The Cytochrome P450 is the major enzyme involved in drug metabolism. CYP enzymes are responsible for the metabolism of most clinically used drugs. Individual variability in CYP activity is one important factor that contributes to drug therapy failure. We have developed a new straightforward TaqMan PCR genotyping assay to investigate the prevalence of the most common allelic variants of polymorphic CYP enzymes CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A5 in the Japanese population. Moreover, we focused on the combination of each genotype for clinical treatment. The genotype analysis identified a total of 139 out of 483 genotype combinations of five genes in the 1,003 Japanese subjects. According to our results, most of subjects seemed to require dose modification during clinical treatment. In the near future, modifications should be considered based on the individual patient genotype of each treatment.  相似文献   
50.
Abstract Objective. Patients with gastroesophageal reflux disease (GERD) also have various extra-esophageal symptoms. Laryngopharyngeal reflux disease (LPRD) is a subtype of GERD associated with globus sensation, but proton pump inhibitor (PPI) therapy achieves disappointing results. This study investigated esophageal motility in GERD patients with globus sensation who were resistant to PPI therapy. Design. The subjects were 350 patients with globus sensation. All patients underwent both laryngoscopy and upper gastrointestinal endoscopy to exclude organic disease. After 4 weeks of treatment with rabeprazole sodium (20 mg daily), the patients were divided into PPI-responsive and PPI-resistant groups. Then we investigated esophageal motility in the PPI-resistant group by a multichannel intraluminal impedance and manometry study. Results. A total of 119 patients (55.6%) were resistant to PPI therapy, among whom 57 patients (47.9%) had abnormal esophageal motility. They included 36 patients (66.4%) with ineffective esophageal motility, 9 patients (14.4%) with achalasia, 6 patients (9.6%) with diffuse esophageal spasm, 5 patients (8%) with nutcracker esophagus, and 1 patient (1.6%) with hypertensive lower esophageal sphincter. There were significant differences of upper esophageal sphincter pressure and esophageal body peristalsis between the patients with PPI-resistant LPRD and healthy controls matched for age and sex. Conclusion. Among patients with PPI-resistant LPRD, 47.9% had abnormal esophageal motility.  相似文献   
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