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71.
Familial hypertrophic cardiomyopathy (HC) can be caused by mutations in 9 different genes encoding sarcomere proteins expressed in cardiac muscle. To date, only 13 different mutations in the cardiac troponin T (cTnT) gene have been reported to cause HC. Clinical characteristics and prognosis associated with mutations of this gene have not been well characterized owing to the small size and composition of affected families. The aim of this study was to determine the characteristic phenotype of patients with HC caused by a novel cTnT gene mutation, Lys273Glu. Two hundred Japanese probands with HC were screened for mutations in the cTnT gene. The Lys273Glu missense mutation was present in 9 persons from 2 unrelated pedigrees. They exhibited different cardiac morphologies: 1 had a dilated cardiomyopathy-like feature, 7 had left ventricular hypertrophy with normal left ventricular systolic function, and the 6 of them had asymmetric septal hypertrophy. A 1-year-old boy was not evaluated with echocardiography. The mean maximum wall thickness was 18.0 +/- 5.5 mm (range 8 to 24). There were 7 histories of sudden death in 1 of the 2 families. The Lys273Glu substitution in the cTnT gene shows a high degree of penetrance (100% in persons aged >20 years), a high incidence of sudden death, and a partial transition from hypertrophic to dilated cardiomyopathy. Because the location of a mutation appears to influence the development of a phenotype, we suggest that the precise definition of the disease-causing mutation can provide important prognostic information about affected members.  相似文献   
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To delineate the usefulness of a clinical pathway for community-acquired pneumonia (CAP) as an educational tool as well as a cost management tool, we conducted a prospective controlled trial including a historical control group. Consecutive CAP patients classified under Category 3 of the American Thoracic Society and admitted to our hospital were evaluated. Using the clinical pathway method, 42 patients were managed between April and December 2000 as the intervention group, and 33 patients received conventional management between April and December 1999 as a historical control. For the intervention group, the clinical pathway, which was a time-task matrix formatted with consideration for guidance for disease treatment, laboratory tests, physical examinations, oxygen saturation monitoring, ambulation, diet, education for the patient and clinical outcomes, was implemented. We determined (1) educational effect, measured using reduction of delay caused by physicians; (2) quality of clinical practice, measured using the success rate of the initial antimicrobial therapy and readmission rate; and (3) economic efficacy, measured using health care cost and length of hospital stay. The delay caused by physicians was reduced by 16% in the Intervention Group (5% vs. 21%; p = 0.045). The success rates of initial antimicrobial therapy in the two groups were similar (85.7% vs. 84.8%). In the intention-to-treat set, the median value of health care cost was reduced by yen 48,055 (yen 277,460 vs. yen 325,515; p = 0.017) and the median length of a hospital stay was shortened by 3 days (8 vs. 11 days; p = 0.0007) in the Intervention Group. In conclusion, the clinical pathway had an educational effect on physicians regarding the management of hospitalized patients with community-acquired pneumonia as well as on the cost management.  相似文献   
74.
Although asymmetric development of the ovary and the oviduct is a unique characteristic in birds, the mechanism of asymmetric development still remains unclear. Recently, degradation of extracellular matrix has been suggested as an important factor related to the regression of the Müllerian duct in mammals. The present study was conducted to examine a possible role of metalloproteinase-2 (MMP-2) in the regression of the right Müllerian duct in the developing chicken embryo. Morphological changes in the Müllerian ducts were studied on day 15 of incubation and mRNA expresseion of MMP-2 was studied on days 12, 15, and 18 of incubation. Morphological observation demonstrated the disappearance of basement membrane in the right Müllerian duct which undergoes the regression. RT-PCR analysis showed that MMP-2 mRNA expression of the right Müllerian duct increased on days 15 and 18 of incubation coincidently with the time of regression. In the right Müllerian duct, regression was prevented by diethylstilbestrol treatment on day 4 of incubation and a coincident decrease in MMP-2 expression was observed when compared to the control group. These results suggest that MMP-2 may be involved in the regression of the right Müllerian duct in the female embryos of the chicken.  相似文献   
75.
B lymphocytes and epithelial cells are the only cell types known to be infected with Epstein-Barr virus (EBV) in normal individuals. Rarely, EBV also infects other cells, including natural killer (NK) cells, almost always in the context of fatal leukaemias or lymphoproliferative disorders. We report on a 6-year-old previously healthy girl who developed fevers and liver function abnormalities for 3 months. The peripheral blood revealed an abnormal expansion of large granular lymphocytes, comprising 24% of the white blood cells. Flow cytometric analysis of the peripheral blood mononuclear cells showed an abnormal increase of CD16-positive NK cells, 62% of which were EBV-infected by in situ EBER-1 hybridization. The circulating B cells were normal in number, but 18% were infected with EBV by in situ EBER-1 hybridization. Approximately 2 years after resolution of all symptoms and continued good health, 35% of the circulating mononuclear cells were EBV-infected, indicative of persistent expansion of EBV-infected cells. We conclude that abnormal expansions of EBV-infected NK and B cells can be associated with a chronic benign course.  相似文献   
76.
Summary The chronic effects of the oral administration of OPC-8212 (3,4-DIHYDRO-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)-quinolinone) on resting hemodynamics and exercise capacity were assessed in 15 patients with congestive heart failure (NYHA II–IV). Doses of 30 or 60 mg per day were given per os over 3.0 weeks on average (range 2–6 weeks). Multigated radionuclide ventriculography and multistage exercise testing were performed before and during OPC-8212 therapy to assess the changes in left ventricular volume and exercise capacity respectively. Systolic blood pressure showed a slight increase (from 123±3 to 129±4 mmHg) during OPC-8212 therapy, while heart rate was unchanged (69±3 vs 67±3 beats/min). The left ventricular end-diastolic volume index decreased from 127±9 to 107±7 ml/m2, and ejection fraction and the P/V index (the ratio of peak systolic pressure to left ventricular end-systolic volume index) increased during OPC-8212 therapy (from 27%±3% to 30%±4% and from 1.5±0.2 to 2.0±0.3 mmHg/ml/m2 respectively). NYHA functional class was improved in 9 of 15 patients, and the average peak work load achieved during exercise testing increased from 27±6 to 47±7 W. No significant adverse effect was observed in any patient. These results indicate that OPC-8212 enhances the inotropic state and, hence, reduces heart size with no change in heart rate. Moreover, it increases exercise capacity. Thus, OPC-8212 is an inotropic agent with promise for application in the long-term treatment of congestive heart failure.  相似文献   
77.
The relationship between Helicobacter pylori (H. pylori) and gastric diseases (e.g. peptic ulcer, MALT lymphoma, and stomach cancer) has been widely accepted. Recent studies have also suggested an association between H. pylori infection and idiopathic thrombocytopenic purpura (ITP). In this study, an H. pylori eradication treatment was administered to 20 ITP patients and elucidated for its effectiveness. Among those 20 patients, H. pylori infection was confirmed in 17 (85%) through a C14 urea breath test, a rapid urease test, or a culture examination of a biopsied sample obtained by gastrointestinal endoscopy. Although the other 3 were negative to H. pylori, the H. pylori eradication treatment was also attempted because no other effective treatments had been established at the time of this study. In the H. pylori eradication treatment, lansoprazole (LPZ) 60 mg bid, amoxicillin (AMPC) 1500 mg bid, and clarithromycin (CAM) 400 mg bid were given to each patient for 7 days. For 4 cases, CAM was replaced with metronidazole (MNZ) 750 mg bid. The patients whose H. pylori infection was not eradicated after the first treatment received the re-eradication treatment with LPZ 60 mg bid, AMPC 1500 mg bid, and MNZ 750 mg bid for 7 days. After the treatments, the success of eradicating H. pylori was confirmed in all 17 H. pylori positive patients. In addition, platelet recovery was obtained in 11/20 patients (55%), which included 2 H. pylori negative patients and 2 patients whose H. pylori eradication was not successful after the first treatment. No relationship was found between the eradication effectiveness and the following clinical parameters: age, gender, previous therapies, disease duration, presence of anti-nucleus antibody, endoscopic atrophic change in the stomach, or kinds of antibiotics used for the treatment. These results support the efficacy of an H. pylori eradication treatment for ITP patients. A noteworthy result of this study was that an increase of platelet count was observed not only in H. pylori positive ITP patients, but also in 2 out of 3 H. pylori negative ITP patients after H. pylori eradication. Further studies are required to elucidate the efficacy of H. pylori eradication therapy in the patients negative for H. pylori.  相似文献   
78.
Thrombophilic dysfibrinogen Tokyo V was identified in a 43-year-old man with recurrent thromboembolism. Based on analyses of the patient fibrinogen genes, the amino acid sequence of the aberrant fibrinogen peptide, and deglycosylation experiments, fibrinogen Tokyo V was shown to have an amino acid substitution of gamma Ala327Thr and possibly extra glycosylation at gamma Asn325 because the mutation confers the N-linked glycosylation consensus sequence Asn-X-Thr. The mutation resulted in impaired function and hypofibrinogenemia (hypodysfibrinogen). Polymerization of fibrin monomers derived from patient fibrinogen was severely impaired with a partial correction in the presence of calcium, resulting in very low clottability. Additionally, a large amount of soluble cross-linked fibrin was formed upon thrombin treatment in the presence of factor XIII and calcium. However, Tokyo V-derived fibrin was resistant to degradation by tissue plasminogen activator (tPA)-catalyzed plasmin digestion. The structure of Tokyo V fibrin appeared severely perturbed, since there are large pores inside the tangled fibrin networks and fiber ends at the boundaries. Taken together, these data suggest that Tokyo V fibrin clots are fragile, so that fibrinolysis-resistant insoluble fibrin and soluble fibrin polymers may be released to the circulation, partly accounting for the recurrent embolic episodes in the patient.  相似文献   
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