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51.
大黄蒽醌衍生物大黄酸(rhein),大黄素(emodin)和芦荟大黄素(aloe-emodin)ip70mg/kg×7d对正常小鼠免疫系统有不同程度的抑制作用,如减轻免疫器官的重量,减少抗体的产生,抑制碳粒廓清功能和腹腔巨噬细胞吞噬功能,降低白细胞数,抑制2,4-二硝基氯苯(DNCB)所致的迟发型超敏反应。大黄酸和大黄素浓度为100μg/ml时对体外[~3H]-TdR、[~H]-Urd参人淋巴细胞也有明显抑制作用。  相似文献   
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Autoimmune hepatitis (AIH) is a severe liver disease affecting all age groups worldwide. Novel basic and clinical aspects of AIH, addressed at a Monothematic Conference in London in September 2015, are highlighted in this review. The diagnosis of AIH relies upon detection of characteristic autoantibodies, hypergammaglobulinemia, and interface hepatitis on liver histology. The International Autoimmune Hepatitis Group (IAIHG) has devised diagnostic scoring systems to help in comparative studies and clinical practice. AIH arises in a genetically predisposed host, when yet unknown triggers – such an encounter with a pathogen – lead to a T cell-mediated immune response targeting liver autoantigens. This immune response is inadequately controlled because regulatory mechanisms are impaired. The mainstay of treatment for AIH is immunosuppression, which should be instituted as soon as the diagnosis is made. Standard treatment regimens include relatively high doses of predniso(lo)ne, which are tapered gradually as azathioprine is introduced. Recent guidelines have described newer treatment regimens and have tightened the goal of therapy to complete normalization of biochemical, serological and histological parameters. Mycophenolate mofetil, calcineurin inhibitors, mTOR inhibitors and biological agents are potential salvage therapies, but should be reserved for selected non-responsive patients and administered only in experienced centers. Liver transplantation is a life-saving option for those patients who progress to end-stage liver disease. Further dissection of cellular and molecular pathways involved in AIH pathogenesis is likely to lead to the discovery of novel, tailored and better tolerated therapies.  相似文献   
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Here, we attempt to reveal how 2-aminofluorene (AF), benzo(α)pyrene (BP) and their major metabolites affect T–cell responses to antigenic and mitogenic stimuli. P-450-related metabolism of these parent compounds to metabolites seems to precede the observed immunosuppression; therefore, we investigated the influence of α-naphthoflavone (P-450 inhibitor) and β-naphthoflavone (P-450 inducer) on BP and AF immunosuppression. We used proliferative responses to concanavalin A and the allogeneic mixed lymphocyte response as correlates of immunosuppression. We also attempted to correlate DNA-adduction to the extent of observed immunosuppression for AF and BP metabolites. These data show that the pathway to the strongest immunosuppressive agents for polycyclic aromatic hydrocarbons and arylamines are divergent and related to metabolism by P450 enzymes.  相似文献   
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IntroductionNonmelanoma skin cancer (NMSC) is the most common malignancy in patients who have received a solid organ transplant. Multiple factors are involved in the onset of posttransplant NMSC.ObjectivesTo analyze the relationship between new immunosuppressive drugs and the onset of NMSC in renal transplant recipients.MethodThis was a combined retrospective and prospective observational study in which we studied 289 patients who received a kidney transplant between January 1996 and December 2010 at Hospital Universitario Doctor Peset in Valencia, Spain.ResultsSeventy-three patients (25.2%) developed 162 NMSCs over a median follow-up of 72 months. There were no statistically significant differences in the onset of NMSC on comparing different induction therapy strategies involving monoclonal and polyclonal antibodies. NMSCs occurred less frequently in patients treated with mammalian target of rapamycin (mTOR) inhibitors than in those treated with other immunosuppressive regimens, although the differences were not statistically significant. Three of 5 patients with recurrent NMSC who were switched from calcineurin inhibitors to mTOR inhibitors developed additional NMSCs despite the change.ConclusionsInduction therapy with monoclonal and polyclonal antibodies in renal transplant recipients is not associated with an increased risk of NMSC. While mTOR inhibitors are associated with a lower risk of posttransplant NMSC, it remains to be determined whether a switch to these drugs is useful in the management of patients who develop multiple NMSCs.  相似文献   
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Background:Diseases caused by melanized fungi include mycetoma, chromoblastomycosis and phaeohyphomycosis. This broad clinical spectrum depends on the dynamic interactions between etiologic agent and host. The immune status of the host influences on the development of the disease, as, an exemple. phaeohyphomicosis is more frequently observed in immunocompromised patients.Objectives:Examine the histological inflammatory response induced by Fonsecaea pedrosoi in several different strains of mice (BALB/c, C57BL/6, Nude and SCID, and reconstituted Nude).Methods:Fonsecaea pedrosoi was cultivated on agar gel and a fragment of this gel was implanted subcutaneously in the abdominal region of female adult mice. After infection has been obtained, tissue fragment was studied histopathologically.Results:There were significant changes across the strains, with the nodular lesion more persistent in Nude and SCID mice, whereas in immunocompetent mice the lesion progressed to ulceration and healing. The histopathological analysis showed a significant acute inflammatory reaction which consisted mainly of neutrophils in the initial phase that was subsequently followed by a tuberculoid type granuloma in immunocompetent mice.Study limitations:There is no a suitable animal model for chromoblastomycosis.Conclusions:The neutrophilic infiltration had an important role in the containment of infection to prevent fungal spreading, including in immunodeficient mice. The fungal elimination was dependent on T lymphocytes. The re-exposure of C57BL/6 mice to Fonsecaea pedrosoi caused a delay in resolving the infection, and appearance of muriform cells, which may indicate that re-exposure to fungi, might lead to chronicity of infection.  相似文献   
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