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High‐mobility group box 1 (HMGB1) has been described in different inflammatory disorders, and the deleterious effects of brain death (BD) may counteract the protection conferred by ischemic preconditioning (IP), the only surgical strategy that is being applied in clinical liver transplantation. Our study examined how HMGB1 may affect preconditioned and unpreconditioned steatotic and nonsteatotic liver grafts from donors after BD (DBDs) for transplantation. HMGB1 was pharmacologically modulated in liver grafts from DBDs, and HMGB1‐underlying mechanisms were characterized. We found that BD decreased HMGB1 in preconditioned and unpreconditioned livers and was associated with inflammation and damage. Exogenous HMGB1 in DBDs activates phosphoinositide‐3‐kinase and Akt and reduces hepatic inflammation and damage, increasing the survival of recipients. Combination of IP and exogenous HMGB1 shows additional benefits compared with HMGB1 alone. This study provides new mechanistic insights into the pathophysiology of BD‐derived liver graft damage and contributes to the development of novel and efficient strategies to ultimately improve liver graft quality.  相似文献   
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Clinically severe disease was produced in ostriches aged 4 weeks by oral infection with a virulent strain of infectious bursal disease virus (vIBDV), namely strain Faragher 52/70. Four days after infection the birds were humanely killed and tissue samples, including thymus, bursa of Fabricius (BF), brain and kidney were collected for examination. Histopathologically, the thymus and BF showed severe lymphoid depletion and necrosis, while immunolabelling with a polyclonal antibody demonstrated abundant viral antigen.  相似文献   
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AIM: The aim of this study was to determine the incidence and severity of gingival overgrowth (GO) induced by tacrolimus (Tcr) compared with ciclosporin A (CiA) in the absence of calcium channel blockers (CCB) in renal transplant recipients. METHODS: Forty patients (20 Tcr and 20 CiA) were evaluated before and 30 and 90 days after kidney transplantation. Demographic (age, gender) and periodontal parameters were recorded for all patients. Patients taking CCB at any time during the study were excluded from the investigation. RESULTS: The mean GO score was significantly lower (p=0.014) in the Tcr group (6.4%) compared with the CiA group (17.9%) after 90 days of immunosuppressive therapy. At 90 days post-transplant, clinically significant GO was observed in four patients of the CiA group and in two of the Tcr group. This difference was not statistically significant (0.66). CONCLUSION: No significant difference in the incidence of clinically significant GO was observed between the CiA and Tcr groups up to 90 days of immunosuppressive therapy.  相似文献   
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This study aimed to characterise canine flow cytometry semen analysis, as well as seminal reactive oxygen species dosage using the Golden Retriever breed as model of study. Moreover, we searched for the influence of muscular dystrophy in Golden Retriever dogs on semen parameters. Thirty‐seven semen samples were obtained from healthy Golden Retrievers (n = 15) and from muscular dystrophy affected dogs (n = 22). Sperm‐rich fractions were analysed by standardised breeding soundness examination in addition to the assay of fluorescence assisted cell sorting for acrosome integrity, mitochondrial activity and DNA fragmentation. Volume of ejaculate, per cent of motile spermatozoa and vigour were similar between groups; there were no differences in the per cent of minor and major defects. Integrity of acrosomal membrane, mitochondrial potential and sperm DNA fragmentation had no significant differences between groups either. Animals from control group had higher concentration of spontaneous seminal oxidative species in comparison with affected animals. Dogs affected by dystrophy had seminal parameters similar to those observed in healthy dogs except for the lower concentration of oxidative species. Future studies aiming to establish reference values for canine seminal parameters should be considered preferably with distinction of breeds.  相似文献   
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