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91.
Aortic valve lesions associated with alkaptonuria tend mostly to be due to aortic valve stenosis, while aortic valve regurgitation is only rarely observed. Herein, a case is reported of severe aortic valve regurgitation and a fibrous strand in a patient with alkaptonuria. A 65-year-old male, with a history of inferior myocardial infarction, presented with symptoms of congestive heart failure. Alkaptonuria was diagnosed based on urine coloration, skin pigmentation and ochronotic arthropathy in the vertebrae and hip. Grade IV aortic valve regurgitation with mild aortic valve stenosis and occlusive disease in the right coronary artery indicated a need for aortic valve replacement and coronary artery bypass grafting. Sclerotic change in the cusps, and shrinkage of the non-coronary cusp, impeded normal coaptation of the aortic valve, and the left-coronary cusp also had a fibrous strand suspending the free margin of the cusp from the aortic wall just above the commissure. The sclerotic change in the cusps, and shrinkage of the non-coronary cusp, appeared to be the causative lesion of aortic valve regurgitation, implying that cardiovascular ochronosis may cause aortic valve regurgitation.  相似文献   
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An interaction effect between the angiotensin-converting enzyme insertion/deletion (ACE I/D) and alpha-adducin (ADD1) Gly460Trp polymorphisms (G460W) on blood pressure regulation has recently been suggested, although its significance in the prognosis of renal function in IgA nephropathy (IgAN) has not been fully investigated. Therefore, we evaluated the clinical manifestations and renal prognosis in 276 Japanese patients with histologically proven IgAN with respect to their ACE I/D and ADD1 G460W polymorphisms. The prognosis of renal function was analyzed by Kaplan-Meier survival curves and multivariate Cox proportional-hazards regression models. Baseline data, including blood pressures, proteinuria, renal function, and incidence of hypertension, were similar for the different genotypes of ACE and ADD1. The individual genotypes taken alone were not associated with the progression of renal dysfunction. However, renal survival of patients with the 460WW polymorphism of ADD1 was significantly worse within the group with the II genotype of ACE (Kaplan-Meier, log rank test; chi2=6.062, P=0.0138) but not for those with other ACE genotypes. In the Cox proportional-hazards regression model with adjustment for clinical risk factors, including hypertension, proteinuria, and no administration of an angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, the 460WW variant of ADD1 was a highly significant and independent risk factor only for patients with the ACE II genotype, with a hazard ratio of 3.65 (P=0.0016), but not for those with other ACE genotypes (hazard ratio=0.65, P=0.2902). These findings suggest an interaction between ACE and ADD1 polymorphisms not only on blood pressure regulation but also on the progression of renal dysfunction in patients with IgAN.  相似文献   
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It is widely accepted that laryngopharyngeal reflux requires more aggressive and prolonged therapy than gastro-esophageal reflux disease. Otolaryngologists often observe that laryngopharyngeal symptoms, such as throat clearing, hoarseness, cough, and globus pharyngeus, are slower to resolve than esophageal symptoms, such as heartburn and regurgitation. The aim of this was to provide empirical evidence to support this observation and to carry out a detailed investigation of the differences between these symptoms. Forty-five patients with laryngopharyngeal and esophageal symptoms received acid-suppression therapy that involved the continuous administration of a proton-pump inhibitor for up to 6 months. We investigated the differences in response to acid-suppression therapy between patients suffering from laryngopharyngeal and esophageal symptoms, respectively, who received upper gastrointestinal endoscopy and were assayed for serum Helicobacter pylori antibodies. The significance of the rate of symptom improvement was estimated by Kaplan-Meier analysis and the logrank test. Laryngopharyngeal symptoms improved significantly more slowly than esophageal symptoms following acid-suppression therapy (49.8 vs. 78.3%, 60 days after the start of acid suppression; P = 0.003). These differences were observed both in patients with erosive esophagitis (P = 0.008) and in H. pylori-seronegative patients (P = 0.001).  相似文献   
96.
The purpose of this study was to investigate whether an association exists between the promoter region of the prostacyclin synthase gene and essential hypertension (EH). Using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method, we discovered a novel single nucleotide polymorphism (SNP), T-192G, in the 5'-flanking region. We performed an association study using the SNP in 200 patients and 200 controls. The allele frequency distribution in the two groups was not significantly different. Thus, this SNP in the PGIS gene is not associated with EH.  相似文献   
97.
On November 15, 2000, a 60-year-old man was admitted to our hospital with progressive dyspnea and right chest pain. He had a 40-year history of occupational asbestos exposure, which began when he was 20 years old. On admission, his chest radiographs showed pleural effusion on the right side, and asbestos bodies were detected in his sputum. Neither a cytological examination of the pleural effusion nor a histological examination of the pleura by percutaneous pleural biopsy revealed malignant cells. In addition, we could not find any other cause for the pleural effusion (such as tuberculosis, collagen disease, or heart failure). In May 2001, the patient also developed pleural thickening and pain in the right hypochondrium, and he was readmitted to our hospital on May 21, 2001. On readmission, an enhanced abdominal CT showed multiple liver tumors, and percutaneous pleural and liver biopsies were performed. The histological findings in the pleura and liver specimens revealed hypocellular collagen tissues without malignant cells. Thus, we could not determine the main cause either of the pleural effusion or of the patient's disease. However, his condition rapidly deteriorated, and he died on August 12, 2001. At the autopsy, bilateral pleural thickening, predominantly on the right side, and invasion of the lungs were observed. The histological findings in the pleural and hepatic tissues revealed hypocellular collagen fibers with a striate pattern and areas of neoplastic spindle cells. He was diagnosed as having malignant desmoplastic mesothelioma with liver metastasis. Cases of malignant desmoplastic mesothelioma have rarely been reported in Japan.  相似文献   
98.
Background: The entire inner ear including the cochlear‐vestibular ganglion arises from a simple epithelium, the otic placode. Precursors for the placode originate from a pool of progenitors located in ectoderm next to the future hindbrain, the pre‐otic field, where they are intermingled with future epibranchial and epidermal cells. While the importance of secreted proteins, such as FGFs and Wnts, in imparting otic identity has been well studied, how precursors for these different fates segregate locally is less well understood. Results: (1) The Notch ligand Delta1 and the Notch target Hes5‐2 are expressed in a part of pre‐otic field before otic commitment, indicative of active Notch signaling, and this is confirmed using a Notch reporter. (2) Loss and gain‐of‐function approaches reveal that Notch signaling regulates both proliferation and specification of pre‐otic progenitors. Conclusions: Our results identify a novel function of Notch signaling in cell fate determination in the pre‐otic field of avian embryos. Developmental Dynamics 244:839–851, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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In patients undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT), post-transplant lung infection is critical for their prognosis. Mycobacterium abscessus complex is not fully recognized as a nontuberculous mycobacteria (NTM) pathogen of post-SCT lung infection. Here, we present three post-allogeneic SCT patients who developed pulmonary infection caused by M. abscessus complex including M. abscessus and M. massiliense. In all three cases, macrolide antibiotics had been administered for bronchiolitis obliterans syndrome (BOS) before the confirmation of their infection, and macrolide resistance was noted in the M. abscessus isolates, one of which resulted in an unfavorable treatment outcome. It is important to consider M. abscessus lung infection as well as other NTM in patients receiving allo-SCT, particularly those receiving macrolide therapy for BOS.  相似文献   
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