Our comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists.
Our comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists.
The extracellular protease urokinase is known to be crucially involved in morphogenesis, tissue repair and tumor invasion by mediating matrix degradation and cell migration. Hepatocyte growth factor/scatter factor (HGF/SF) is a secretory product of stromal fibroblasts, sharing structural motifs with enzymes of the blood clotting cascade, including a zymogen cleavage site. HGF/SF promotes motility, invasion and growth of epithelial and endothelial cells. Here we show that HGF/SF is secreted as a single‐chain biologically inactive precursor (pro‐HGF/SF), mostly found in a matrix‐associated form. Maturation of the precursor into the active alpha beta heterodimer takes place in the extracellular environment and results from a serum‐dependent proteolytic cleavage. In vitro, pro‐HGF/SF was cleaved at a single site by nanomolar concentrations of pure urokinase, generating the active mature HGF/SF heterodimer. This cleavage was prevented by specific urokinase inhibitors, such as plasminogen activator inhibitor type‐1 and protease nexin‐1, and by antibodies directed against the urokinase catalytic domain. Addition of these inhibitors to HGF/SF responsive cells prevented activation of the HGF/SF precursor. These data show that urokinase acts as a pro‐HGF/SF convertase, and suggest that some of the growth and invasive cellular responses mediated by this enzyme may involve activation of HGF/SF.
Scatter factor (SF), a secretory protein of fibroblasts, dissociates and increases the motility of epithelial cells and may be involved in cell migration processes during embryogenesis and tumor progression. Hepatocyte growth factor (HGF), a protein isolated from serum of patients with liver failure, is a potent mitogen for hepatocytes and is thought to play a role in liver regeneration. Here we present structural and functional evidence that human SF and human HGF (and also the human lung fibroblast-derived mitogen) are identical proteins encoded by a single gene, since (a) no major difference could be found by protein sequencing, by cDNA analysis, and by immunological comparison and (ii) SF in fact acts as a hepatocyte growth factor-i.e., stimulates DNA synthesis of primary hepatocytes-whereas HGF exhibits scatter factor activity-i.e., dissociates and induces invasiveness of various epithelial cells. The human SF/HGF gene was localized to chromosome bands 7q11.2-21. These results have important consequences for further studies on the involvement of SF/HGF as a modulator of cellular growth and motility in embryonal, malignant, and regenerative processes.
The Japanese Society of Gastroenterology revised the evidence-based clinical practice guidelines for liver cirrhosis in 2015. Eighty-three clinical questions were selected, and a literature search was performed for the clinical questions with use of the MEDLINE, Cochrane, and Igaku Chuo Zasshi databases for the period between 1983 and June 2012. Manual searching of the latest important literature was added until August 2015. The guidelines were developed with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. This digest version in English introduces selected clinical questions and statements related to the management of liver cirrhosis and its complications. Branched-chain amino acids relieve hypoalbuminemia and hepatic encephalopathy and improve quality of life. Nucleoside analogues and peginterferon plus ribavirin combination therapy improve the prognosis of patients with hepatitis B virus related liver cirrhosis and hepatitis C related compensated liver cirrhosis, respectively, although the latter therapy may be replaced by direct-acting antivirals. For liver cirrhosis caused by primary biliary cirrhosis and active autoimmune hepatitis, urosodeoxycholic acid and steroid are recommended, respectively. The most adequate modalities for the management of variceal bleeding are the endoscopic injection sclerotherapy for esophageal varices and the balloon-occluded retrograde transvenous obliteration following endoscopic obturation with cyanoacrylate for gastric varices. Beta-blockers are useful for primary prophylaxis of esophageal variceal bleeding. The V 2 receptor antagonist tolvaptan is a useful add-on therapy in careful diuretic therapy for ascites. Albumin infusion is useful for the prevention of paracentesis-induced circulatory disturbance and renal failure. In addition to disaccharides, the nonabsorbable antibiotic rifaximin is useful for the management of encephalopathy. Anticoagulation therapy is proposed for patients with acute-onset or progressive portal vein thrombosis.
Abstract. Hyperglycemia seems to be an important causative factor in the development of micro-and macrovascular complications in patients with diabetes. Several hypotheses have been proposed to explain the adverse effects of hyperglycemia on vascular cells. Both protein kinase C (PKC) activation and oxidative stress theories have increasingly received attention in recent years. This article shows a PKC-dependent increase in oxidative stress in diabetic vascular tissues. High glucose level stimulated reactive oxygen species (ROS) production via a PKC-dependent activation of NAD(P)H oxidase in cultured aortic endothelial cells, smooth muscle cells, and renal mesangial cells. In addition, expression of NAD(P)H oxidase components were shown to be upregulated in vascular tissues and kidney from animal models of diabetes. Furthermore, several agents that were expected to block the mechanism of a PKCdependent activation of NAD(P)H oxidase clearly inhibited the increased oxidative stress in diabetic animals, as assessed by in vivo electron spin resonance method. Taken together, these findings strongly suggest that the PKC-dependent activation of NAD(P)H oxidase may be an essential mechanism responsible for increased oxidative stress in diabetes.Hyperglycemia seems to be an important causative factor in the development of micro-and macrovascular complications in patients with diabetes (1,2). Various pathophysiological and biochemical mechanisms have been proposed to explain the adverse effects of hyperglycemia on vascular cells (3-6). Among various possible mechanisms, it is widely accepted that high glucose level and a diabetic state induce the persistent activation of the diacylglycerol (DAG)-protein kinase C (PKC) pathway in micro-and macrovascular tissues of diabetic animals and of patients with diabetes (7-12). Because PKC is a critical intracellular signaling molecule that can regulate many vascular functions, it is to be expected that activation of PKC may cause alteration in various vascular functions in diabetes. However, accumulating evidence has shown that oxidative stress also may play a role in the development of diabetic vascular complications. A number of in vitro and in vivo studies suggest that the production of reactive oxygen species (ROS) is increased in diabetes (13-16). It has been postulated that ROS production in diabetes may be enhanced by hyperglycemia through various mechanisms such as enhanced formation of glycation products (17), altered polyol pathway activity (18), and increased superoxide release from mitochondria (19). In contrast, attention is increasingly focused on NAD(P)H oxidase as the most important source of ROS production in blood vessels (20 -23). Recent reports have implicated that this oxidase may be involved in the pathophysiology of various vascular diseases, including hypercholesterolemia (24), atherosclerosis (25-27), and hypertension (28). In this review, we show that a PKC-dependent activation of NAD(P)H oxidase may be an essential mechanism responsible for increased ROS ...
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