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The authors attempted to clarify the exact cell components of neurofibroma by immunohistochemical and ultrastructural studies. Materials were randomly selected, 40 cases of neurilemoma and neurofibroma (-tosis) in addition to 2 cases of tumors composed exclusively of perineurial cells and three cases of normal peripheral nerve. The applied markers included antisera of S-100 protein for Schwann cells, blood coagulation factor XIIIa for endoneurial fibroblasts or perineurial cells, and laminin and collagen type IV for the basement membrane. S-100 protein was demonstrated only in normal or neoplastic Schwann cells, but not in perineurial cells. On the other hand, factor XIIIa was often recognized in endoneurial fibroblasts and perineurial cells, but not in Schwann cells. Neurofibroma was basically composed of a mixture of Schwann cells, perineurial cells, and endoneurial fibroblasts, the population of each type of cell differing according to the case and area within a given tumor. Perineurial cell tumor exclusively composed of perineurial cells, though rare, appears to be a definite entity, and its characteristic histological and ultrastructural features were described.  相似文献   
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Background and Aim: We compared endoscopic findings of the frequency scale for the symptoms of gastroesophageal reflux disease (FSSG), a written questionnaire developed in Japan, to that for the questionnaire for the diagnosis of reflux esophagitis (QUEST) for the diagnosis of reflux esophagitis. Methods: We registered 475 patients with untreated symptoms of upper abdominal pain (male/female: 252/223, average age 52.4 ± 17.8 years). Subjects were assessed first with the FSSG and QUEST questionnaires, then by endoscopy, before allocation to a gastric ulcer (GU), duodenal ulcer (DU), gastroesophageal reflux disease (GERD) or functional dyspepsia (FD) group. Results: On the basis of the endoscopic findings the diagnoses for the 475 subjects were as follows: FD 52.2%, DU 7.6%, GU 7.8%, and GERD 32.4% (Grade M 10.1%, Grade A + B 20.2%, Grade C + D 2.3%). There was no difference between the FSSG and QUEST in sensitivity, specificity or accuracy for any condition. The FSSG score rose with increasing endoscopic severity of GERD, but there was no correlation between the QUEST score and endoscopic severity. The FSSG total score was inferior to QUEST in terms of distinguishing GERD from other conditions, but when only the questions relating to reflux symptoms were used, the FSSG was able to distinguish GERD from other conditions as well as QUEST. Conclusions: The FSSG score reflects the severity of the endoscopic findings of GERD.  相似文献   
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BACKGROUND/AIMS: Histamine H2 receptor antagonists are considered to exert their effects on gastric acid secretion more rapidly than proton pump antagonists. However, there are no reports concerning the direct interaction of a histamine H2 receptor antagonist with the human H2 receptor in terms of onset of action. This study aims to characterize how rapidly famotidine and ranitidine, the most widely used histamine H2 receptor antagonists, interact with the human histamine H2 receptor. METHODS: HEK293 cell lines, stably expressing human histamine H2 receptors, were obtained. The dose- and time-dependent effects of famotidine and ranitidine on [3H]-tiotidine binding and histamine-stimulated cAMP production were analyzed. RESULTS: Ranitidine inhibited both [3H]-tiotidine binding and histamine-stimulated cAMP production more promptly than did famotidine. Inhibition of histamine-stimulated cAMP production by Cmax doses of famotidine (20 mg p.o.) and ranitidine (150 mg p.o.) peaked by 15 and 2 min, respectively. [3H]-tiotidine binding was not saturated by 60 min at the famotidine Cmax, while the ranitidine Cmax had produced saturation by 15 min. CONCLUSION: Ranitidine inhibits the human histamine H2 receptor very rapidly.  相似文献   
5.
BACKGROUND/AIMS: The presence of antibodies to the 210-kDa glycoprotein of the nuclear pore complex (gp210) is highly indicative of primary biliary cirrhosis (PBC). However, the significance of anti-gp210 antibody titers for monitoring PBC remains unresolved. METHODS: We used an ELISA with a gp210 C-terminal peptide as an antigen to assess serum antibody titers in 71 patients with PBC. RESULTS: Patients were classified into three groups: Group A in whom anti-gp210 titers were sustained at a high level, Group B in whom anti-gp210 status changed from positive to negative under ursodeoxycholic acid (UDCA) therapy, Group C in whom anti-gp210 antibodies were negative at the time of diagnosis. The rate of progression to end-stage hepatic failure was significantly higher in group A (60%) as compared to groups B (0%) and C (4.2%). The sustained antibody response to gp210 was closely associated with the severity of interface hepatitis. The significance of anti-gp210 antibody was confirmed by National Hospital Organization Study Group for Liver Disease in Japan. CONCLUSIONS: The serial quantitation of serum anti-gp210-C-terminal peptide antibodies is useful for monitoring the effect of UDCA and for the early identification of patients at high risk for end-stage hepatic failure.  相似文献   
6.
BACKGROUND/AIMS: Production of nitric oxide (NO) in the liver is believed to be a critical factor for carbohydrate and energy metabolism in endotoxin shock. The present study focuses on the involvement of NO produced by inducible nitric oxide synthase (iNOS) in glycogen synthesis and energy metabolism stimulated by insulin.METHODS: Primary hepatocytes prepared from wild-type and iNOS knockout (iNOS(-/-)) mice were employed.RESULTS: Incubation of wild-type hepatocytes with a combination of cytokines (interleukin-1beta, tumor necrosis factor-alpha and interferon-gamma) and lipopolysaccharide (cytokines/LPS) inhibited insulin-stimulated glycogen synthesis and adenosine triphosphate (ATP) increase, and decreased the ketone body ratio (KBR) at 8-12 h, concomitant with expression of iNOS protein and NO production. While the glycogen synthesis was suppressed by cytokines/LPS, reduction of the ATP increase and a decrease in KBR by cytokines/LPS were not observed in iNOS(-/-) hepatocytes. Further, N(G)-monomethyl-L-arginine, a NOS inhibitor, reversed the inhibition of ATP increase and decrease in KBR by cytokines/LPS, but not the inhibition of glycogen synthesis. Conversely, addition of S-nitroso-N-acetylpenicillamine, a NO donor, inhibited the insulin-stimulated ATP increase synthesis in iNOS(-/-) hepatocytes, but not the insulin-stimulated glycogen synthesis.CONCLUSIONS: These results demonstrate that NO mediates the suppression of insulin-stimulated energy metabolism, but not glycogen synthesis, in cytokines/LPS-treated hepatocytes.  相似文献   
7.
Previous studies have reported negative impacts of long‐term dialysis on kidney transplantation (KTx) outcomes. However, advances in surgical techniques, immunosuppressive therapies, and post‐transplant monitoring have led to an impressive increase in patient and allograft survival. Thus, the number of KTx among patients on long‐term dialysis is increasing. We evaluated the influence of dialysis duration on the outcome of living donor KTx. Between January 2000 and October 2011, we performed 1098 first KTx from living donors in adults (>18 years). We divided the patients into six groups, A group: pre‐emptive kidney transplantation, B group: <24 months duration of dialysis, C group: 25–60 months duration, D group: 61–120 months duration, E group: 121–240 months duration, and F group: ≥241 months duration. The 5‐year patient survival rates were 95.7, 98.8, 99.0, 99.0, 97.3, and 100% in groups A–F, respectively. The 5‐year graft survival rates were 91.3, 95.6, 94.2, 96.3, 90.7, and 100% in groups A–F, respectively. No significant differences were observed in patient or graft survival among the six groups. Longer dialysis duration was correlated with lower rates of preoperative hypertension and diabetes mellitus. Survivors of long‐term dialysis tended to be in good compliance with self‐management. If recipients of living KTx have few complications, good prognoses are expectable even if dialysis periods are very long.  相似文献   
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Background

We conducted a multicenter randomized clinical trial to determine the optimal treatment strategy against chronic hepatitis C virus (HCV) with genotype 1b and a high viral load (G1b/high).

Methods

The study subjects included 153 patients with G1b/high. Patients were initially treated with PEG-IFNα-2a alone and then randomly assigned to receive different treatment regimens. Ribavirin (RBV) was administered to all patients with HCV RNA at week 4. Patients negative for HCV RNA at week 4 were randomly assigned to receive PEG-IFNα-2a (group A) or PEG-IFNα-2a/RBV (group B). Patients who showed HCV RNA at week 4 but were negative at week 12 were randomly assigned to receive weekly PEG-IFNα-2a (group C) or biweekly therapy (group D). Patients who showed HCV RNA at week 12 but were negative at week 24 were randomly assigned to receive PEG-IFNα-2a/RBV (group E) or PEG-IFNα-2a/RBV/fluvastatin (group F).

Results

Overall, the rate of sustained virological response (SVR) was 46 % (70/153). The total SVR rate in the group (A, D, and F) of response-guided therapy was significantly higher than that in the group (B, C, and E) of conventional therapy [70 % (38/54) versus 52 % (32/61), p = 0.049]. Although IL28-B polymorphism and Core 70 mutation were significantly associated with efficacy, patients with rapid virological response (RVR) and complete early virological response (cEVR) achieved high SVR rates regardless of their status of IL-28B polymorphism and Core 70 mutation.

Conclusion

In addition to knowing the IL-28B polymorphism and Core 70 mutation status, understanding the likelihood of virological response during treatment is critical in determining the appropriate treatment strategy.  相似文献   
10.
Perturbation of transforming growth factor (TGF)-β signaling in hepatocytes persistently infected with hepatitis viruses promotes both fibrogenesis and carcinogenesis (fibro-carcinogenesis). Insights into hepatocytic fibro-carcinogenesis have emerged from recent detailed analyses of context-dependent and cell type–specific TGF-β signaling processes directed by multiple phosphorylated forms (phospho-isoforms) of Smad mediators. In the course of hepatitis virus–related chronic liver diseases, chronic inflammation, ongoing viral infection, and host genetic/epigenetic alterations additively shift hepatocytic Smad phospho-isoform signaling from tumor suppression to fibro-carcinogenesis, accelerating liver fibrosis and increasing risk of hepatocellular carcinoma (HCC). After successful antiviral therapy, patients with chronic hepatitis can experience less risk of HCC occurrence by reversing Smad phospho-isoform signaling from fibro-carcinogenesis to tumor suppression. However, patients with cirrhosis can still develop HCC owing to sustained, intense fibro-carcinogenic signaling. Recent progress in understanding Smad phospho-isoform signaling should permit use of Smad phosphorylation as a tool predicting the likelihood of liver disease progression, and as a biomarker for assessing the effectiveness of interventions aimed at reducing fibrosis and cancer risk.  相似文献   
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