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Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) protein levels increase in particulate fractions in association with cell death in HEK293 cells, S49 cells, primary thymocytes, PC12 cells, and primary cerebral cortical neuronal cultures. Subcellular fractionation and immunocytochemistry reveal that this increase primarily reflects nuclear translocation. Nuclear GAPDH is tightly bound, resisting extraction by DNase or salt treatment. Treating primary thymocytes, PC12 cells, and primary cortical neurons with antisense but not sense oligonucleotides to GAPDH prevents cell death. Because cell-death-associated nuclear translocation of GAPDH and antisense protection occur in multiple neuronal and nonneuronal systems, we propose that GAPDH is a general mediator of cell death and uses nuclear translocation as a signaling mechanism.  相似文献   
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Wilson disease (WD) is a hereditary disorder, with recessive transmission and genetic heterogeneity. Several mutations of ATP7B, the gene underlying WD, were reported in many ethnic groups. In this study, mutation screening in ATP7B of 56 Saudi Arabian WD patients was undertaken. The clinical data of all patients were recorded. The entire ATP7B coding sequence, including intron-exon boundaries were screened for mutation by the polymerase chain reaction (PCR)-based mutation detection technique and DNA sequencing. Thirty-nine patients were symptomatic at presentation and 17 subjects were pre-symptomatic siblings of affected patients. Fourteen patients had neurological, 11 patients had mixed (hepatic and neurological), and 14 patients had hepatic presentations. Family history suggestive of WD was present in 72% of cases and 68% had consanguineous parents. Genetic analysis showed disease-causing mutations in three exons (exons 8, 19 and 21) of the ATP7B gene in 28 patients (50%). Mutations in exons 21 (18 cases) and 19 (one case) were unique for Saudis. This large series of Saudi patients with WD has shown wide variability in the genomic substrate of WD. There is no correlation between genotype and clinical presentation.  相似文献   
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Over the last few decades the there has been a huge increase in the incidence of oesophageal adenocarcinoma, surpassing that of any other solid tumour. Barrett's oesophagus is recognised as a pre-malignant cursor. Surveillance programmes have evolved to monitor Barrett's oesophagus, with the intention to detect early malignant transformation. Using photosensitive agents photodiagnosis is developing to detect this transformation before it is visible endoscopically to allow early treatment. Photodynamic therapy is a non-thermal endoscopic ablative technique, which incorporates the same photosensitive agents to treat Barrett's oesophagus as well as malignant disease. In this article we review the present status of photodiagnosis and photodynamic therapy in the management of Barrett's oesophagus and early oesophageal carcinoma.  相似文献   
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Surgical Management of Marfan Syndrome in Children   总被引:1,自引:0,他引:1  
Between August 1983 and January 1991, seven patients with Marfan syndrome underwent surgery for severe cardiovascular complications. The mean age at presentation was 5.7 months (range 4 to 9 months) in the infant group (n = 3), and 13.3 years (range 10 to 16 years) in a group of older children (n = 4). The primary indications for surgery in the infant group (performed at a mean of 3 years after diagnosis) were ascending aortic aneurysm with valvar regurgitation in one patient, and severe mitral valve prolapse with regurgitation in two. In the older group, surgical indications (performed at a mean of 2.8 years after diagnosis) were ascending aortic aneurysm with valvar regurgitation in three patients and acute aortic dissection in one. For aortic surgery, a composite valved conduit was used in four patients, and an aortic homograft in one. For mitral valve surgery, mechanical prostheses were used. Ail patients survived the primary operation. Over a mean follow-up of 17.5 patient-years (range 1 to 9 years), two patients in the infant Marfan group went on to further successful surgery (prosthetic mitral valve replacement and aortic root repair with aortic homograft) at a mean interval of 4.3 years after the Initial surgery. Our results suggest that the major cardiovascular risk factors of Marfan syndrome in the young, even in those diagnosed during infancy, have been favorably changed by surgery with an encouraging medium-term outlook. The correct timing of surgery is aided by echocardiography. (J Card Surg 1994;9:50–54)  相似文献   
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