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Background: The aim of this study was to investigate the effect of pretransplant culture on the survival of pancreatic islet grafts, and to determine the biological characteristics of isolated islets during pretransplant culture. Methods: The survival of islets from Wistar rats, transplanted to diabetic C57BL/B6 mice, was compared between fresh islets and cultured islets. A comprehensive gene expression analysis was employed to investigate biological processes during pretransplant culture, and in vitro validation studies were performed. Results: Survival of cultured xenografts was significantly prolonged as compared to that of fresh islets (fresh: 12.5 ± 1.9 days, 1-day cultured: 16.0 ± 1.3 days (p= 0.017), 3-day cultured: 17.0 ± 2.6 days (p= 0.014)). Comprehensive gene expression analysis identified significant upregulation of annotated functions associated with inflammation in cultured groups. Six proinflammatory genes, including heme oxygenase 1 (HO-1) and IL-6, were significantly upregulated during culture. Validation studies revealed significantly higher levels of IL-6 in the supernatant of cultured islets and HO-1 in the cultured islets when compared with fresh islets. Conclusion: Transplantation of cultured islets induced significant but minimal prolongation of graft survival in xenogeneic combinations. Comprehensive analysis of gene expression in cultured islets showed biological processes associated with proinflammation during culture.  相似文献   
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Background and Aim: Topical mesalamine or corticosteroid has shown efficacy in patients with ulcerative proctitis, but patients often become refractory to these interventions. Xilei San is a herbal preparation with evidence of anti‐inflammatory effects. We evaluated the efficacy of topical Xilei San in ulcerative proctitis patients. Methods: In a double blind setting, 30 patients with intractable ulcerative proctitis despite ≥ 4 weeks of topical mesalamine or corticosteroid were randomly assigned to True (n = 15) and placebo (n = 15). Patients in True received suppository Xilei San (0.1 g/dose per day of Xilei San), the other 15 received placebo suppository. The initial efficacy was evaluated on day 14. Primary endpoint of the trial was avoiding relapse during 180 days, relapse meant recurrence of active disease. Riley's index was applied for endoscopic and histological evaluations, while patients' quality of life was evaluated by an inflammatory bowel disease questionnaire. Results: On day 14, the number of patients who achieved remission, clinical activity index ≤ 4 in True was significantly higher versus placebo (P < 0.04). Likewise, at day 180, an 81.8% of patients in True were without relapse versus 16.7% in placebo (P < 0.001). Further, significant endoscopic (P < 0.01), histological (P < 0.02) and inflammatory bowel disease questionnaire (P < 0.04) improvements were observed in True, but not in placebo. Conclusions: This is the first controlled investigation showing significant clinical and endoscopic efficacy for Xilei San in patients with intractable ulcerative proctitis. Topical Xilei San was well tolerated, and was without safety concerns.  相似文献   
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Leukocytapheresis (LCAP) is a safe, unique therapy pertaining to intractable rheumatoid arthritis (RA) even in cases of drug allergy or infectious states. To investigate how to represent LCAP efficacy, we have conducted gene expression analyses from the peripheral blood of RA patients treated with non‐woven polyethylene terephthalate filters. Peripheral blood samples were collected immediately before and after treatment from eight RA patients who received LCAP. Among these patients, all of them achieved 20% improvement in the core set of the American College of Rheumatology (ACR20), and thus, they were confirmed as LCAP responders. Gene expression analysis was done with a high‐resolution DNA microarray. The results of each of the two groups' gene expression values (immediately before and after LCAP) were calculated using Welch's t‐test. Calculations were performed with a statistical software R.basic package: if the P‐value was less than 0.05, this was seen as a significant change. In a comparison of 25 370 gene expressions, the number of genes showing a P‐value < 0.05 in the upregulating group was 2110, and in the downregulating group it was 1864. The results of pathway analysis using the MetaCore program indicate that gene groups work for cytoskeletal remodeling are upregulated, and genes related to immune responses, such as antigens presenting via major histocompatibility complex class I and II, are downregulated just after LCAP. These findings may relate to LCAP efficacy for RA patients, but this needs further investigation.  相似文献   
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The EBV is a human γ‐herpesvirus associated with various neoplasms. It is responsible for causing cancers of B, T, and NK cells as well as cells of epithelial origin. Such diversity in target cells and the complicated steps of oncogenesis are perplexing when we speculate about the mechanisms of action of EBV‐positive cancers. Here, we first note three common features that contribute to the development and maintenance of EBV‐positive cancers: effects of EBV oncogenes, immunosuppression and evasion/exploitation of the immune system, and genetic and epigenetic predisposition/alteration of the host genome. Then, we demonstrate the mechanisms of oncogenesis and the means by which each EBV‐positive cancer develops, with particular focus on the mode of EBV infection. The EBV has two alternative life cycles: lytic and latent. The latter is categorized into four programs (latency types 0–III) in which latent viral genes are expressed differentially depending on the tissue of origin and state of cells. The production of viral latent genes tends to decrease with an increase in time, and, in an approximate manner, the expression levels of viral genes are inversely correlated with the degree of abnormalities in the host genome. Occasional execution of the viral lytic cycle also contributes to oncogenesis. Understanding this life cycle of the EBV and its relevance in oncogenesis may provide valuable clues to the development of effective therapies for the associated cancers. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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