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51.
In this study, we compared a recently developed PCR-restriction fragment length polymorphism (PCR-RFLP) assay with pulsed-field gel electrophoresis (PFGE) using three different Shiga toxin-producing Escherichia coli (STEC) strains to understand whether repeated subculture in vitro and prolonged storage at room temperature affect the RFLP patterns of STEC. The PFGE profiles of the STEC strains changed by 1 to 8 fragments after repeated subculture and prolonged storage; one strain was no longer clonal after repeated subculture compared to the original isolate according to the Tenover criteria. In contrast, RFLP patterns obtained by PCR-RFLP were identical after repeated subculture and prolonged storage. These data clearly indicate that the PCR-RFLP assay which is based on the diversity of region V, a regulatory region of Stx-phage, was not affected by repeated subculture and prolonged storage and is a more practical and reliable method for molecular typing of STEC strains.  相似文献   
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Protein kinases represent a large and diverse family of evolutionarily related proteins that are abnormally regulated in human cancers. Although genome sequencing studies have revealed thousands of variants in protein kinases, translating “big” genomic data into biological knowledge remains a challenge. Here, we describe an ontological framework for integrating and conceptualizing diverse forms of information related to kinase activation and regulatory mechanisms in a machine readable, human understandable form. We demonstrate the utility of this framework in analyzing the cancer kinome, and in generating testable hypotheses for experimental studies. Through the iterative process of aggregate ontology querying, hypothesis generation and experimental validation, we identify a novel mutational hotspot in the αC‐β4 loop of the kinase domain and demonstrate the functional impact of the identified variants in epidermal growth factor receptor (EGFR) constitutive activity and inhibitor sensitivity. We provide a unified resource for the kinase and cancer community, ProKinO, housed at http://vulcan.cs.uga.edu/prokino .  相似文献   
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Ischemia often precedes neovascularization. Inocular neovascularization, such as occurs in diabetic retinopathy, a diffusible angiogenic factor has been postulated to be produced by ischemicretina and to lead to neovascularization of theretina, optic nerve, or iris. However, no angiogenic factor has been conclusively identified that satisfies this hypothesis. Vascular endothelial growth factor/vascular permeability factor, hereafter referred to as VEGF, is a likely candidate for an ocular angiogenic factor because it is a secreted mitogen, specific for endothelial cells, and is upregulated by hypoxia. We investigated the association of VEGF with the development of experimental iris neovascularization in the cynomolgus monkey. Following theproduction of retinal ischemia by laser occlusion of all branch retinal veins, VEGF was increased in the aqueous fluid, and the aqueous VEGF levels changed synchronously and proportionally with the severity of iris neovascularization. Northern analysis and in situ hybridization revealed that VEGF messenger RNA is upregulated in the ischemic retina. These observations support the hypothesis that ocular neovascularization is regulated by a diffusible factor and identify VEGF as a likely candidate for a retina-derived vascular permeability and angiogenesis factor in vivo.  相似文献   
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Pierson syndrome (OMIM 609049) is typically characterized by congenital nephritic syndrome and peculiar ocular anomalies with microcoria. It is caused by mutations in LAMB2, which encodes laminin β2. Approximately 50 mutations of LAMB2 from approximately 40 unrelated families have been identified; however, most of them were from Western countries. Although three patients in Asia with mutations of LAMB2 have been reported, they were not typical cases. We report the first Japanese case of Pierson syndrome with proven causative LAMB2 mutations. She presented with congenital nephrotic syndrome and bilateral microcoria at birth, and developed end‐stage renal disease at 2 months of age. This is the first report of a typical case from Asia. LAMB2 analysis by direct sequencing revealed the compound heterozygous mutations c.3974_3975insA (p.N1325KfsX1331, maternal, novel) in exon 25 and c.4519C>T (p.Q1507X, paternal) in exon 27. The phenotype due to LAMB2 mutations appears to be similar between different ethnic groups.  相似文献   
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BACKGROUND: The aim of this study was to evaluate the effect of metformin in addition to insulin therapy in adolescents and young adults with type 1 diabetes mellitus. METHODS: Nine patients, two males and seven females, aged 18.1 +/- 3.0 years, with type 1 diabetes mellitus were studied. They were relatively overweight with a body mass index (BMI) of 24.2 +/- 1.8 and had high levels of HbA1c at 9.5 +/- 1.2% despite high doses of insulin of 74.0 +/- 31.2 U/day. Metformin at the dose of 500-750 mg daily was administered to the patients in addition to insulin therapy for 1 year. RESULTS: HbA1c, BMI and insulin dose were compared before 1 year without metformin therapy, at baseline, and at 3, 6 and 12 months during the use of metformin in addition to insulin therapy. HbA1c lowered (8.6 +/- 1.4**, 8.4 +/- 1.3**, 8.4 +/- 1.2*%), BMI was reduced (23.9 +/- 1.7*, 23.8 +/- 1.8, 23.5 +/- 1.8*), and insulin requirement decreased (69.8 +/- 29.7*, 68.7 +/- 29.8**, 67.3 +/- 29.1**U/d) significantly after the start of metformin therapy (*P < 0.05, **P < 0.01 vs at baseline). There were no adverse events, not even lactic acidosis, during the study period. CONCLUSION: Metformin is safe and may represent a useful adjunct to the management of type 1 diabetes mellitus in adolescents and young adults who have poor glycemic control despite a large amount of insulin.  相似文献   
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