0000000000217316

AUTHOR

Jan Schmidt

Disturbance of hepatic and intestinal microcirculation in experimental liver cirrhosis

AIM: To analyze hepatic, mesenteric and mucosal microcirculation and leukocyte-endothelium interaction (LEI) in a rat model with liver cirrhosis. METHODS: Hepatic cirrhosis was induced in Wistar rats by gavage with carbon tetrachloride, and intravital videomicroscopy was performed in liver, mesentery and small intestine mucosa. Special emphasis is given on microcirculatory and morphometric changes during cirrhotic portal hypertension. RESULTS: LEI was influenced significantly in the cirrhotic liver but not in the gut. Blood flow measurement showed significant differences among liver, main mesenteric vessels and the mucosa. The results of our study indicate that liver cirrhosis leads to alte…

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A Critical Regulatory Role of Leucin Zipper Transcription Factor c-Maf in Th1-Mediated Experimental Colitis

Abstract In this study, we investigated the role of c-Maf, a transcription factor known to induce IL-4 production, in inflammatory bowel diseases and experimental colitis. Although Crohn′s disease (CD) is associated with low IL-4 production by T-bet-expressing Th1 cells in the lamina propria, surprisingly a higher expression of c-Maf in these cells was found as compared with control patients. The relevance of this finding was further evaluated in an animal model of CD induced by adoptive transfer of CD4+CD62L+ T cells in RAG-deficient mice. In this Th1-mediated model, an increase of c-Maf-expressing T lymphocytes in the lamina propria over time was observed. Interestingly, adoptive transfer…

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Immune escape mechanism: defective resting and stimulated leukocyte-endothelium interaction in hepatocellular carcinoma of the rat.

Hepatocellular carcinoma represents an increasing therapeutic challenge due to its high incidence and early metastasis. Numerous studies have demonstrated the influence of the vascular system on tumor growth and development. In addition, the role of leukocyte-endothelium interaction in tumor vessels is of particular significance with regard to immunological tumor therapy. In this study we used an experimental in vivo animal model that allows a quantitative analysis on vessel morphology, microcirculation, and leukocyte-endothelium interaction. The vessel architecture in tumor tissue was found to be extremely heterogeneous, with a consecutively variable blood flow velocity. Following superfus…

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The transcription factor NFATc2 controls IL-6–dependent T cell activation in experimental colitis

The nuclear factor of activated T cells (NFAT) family of transcription factors controls calcium signaling in T lymphocytes. In this study, we have identified a crucial regulatory role of the transcription factor NFATc2 in T cell–dependent experimental colitis. Similar to ulcerative colitis in humans, the expression of NFATc2 was up-regulated in oxazolone-induced chronic intestinal inflammation. Furthermore, NFATc2 deficiency suppressed colitis induced by oxazolone administration. This finding was associated with enhanced T cell apoptosis in the lamina propria and strikingly reduced production of IL-6, -13, and -17 by mucosal T lymphocytes. Further studies using knockout mice showed that IL-…

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Antibodies against tumor necrosis factor (TNF) induce T-cell apoptosis in patients with inflammatory bowel diseases via TNF receptor 2 and intestinal CD14⁺ macrophages.

Background & Aims The anti–tumor necrosis factor (TNF) antibodies infliximab, adalimumab, and certolizumab pegol have proven clinical efficacy in Crohn's disease. Here, we assessed the effects of anti-TNF antibodies on apoptosis in inflammatory bowel disease (IBD). Methods CD14 + macrophages and CD4 + T cells were isolated from peripheral blood and lamina propria mononuclear cells from patients with IBD and control patients. Cell surface markers and apoptosis were assessed by immunohistology and fluorescence-activated cell sorting techniques. Results Lamina propria CD14 + macrophages showed significantly more frequent and higher membrane-bound TNF (mTNF) expression than CD4 + T cells in IBD…

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Evaluation of domino liver transplantations in Germany.

Summary A retrospective multicenter study has been conducted to evaluate domino liver transplantations (DLTs) in Germany. The study provides insight into survival and features having an impact on the assessment of neuropathy after DLT. In addition, a neurologic follow-up program with a scheme to estimate the likelihood of de novo amyloidosis is presented. A series of 61 DLTs at seven transplant centers in Germany was enrolled. The mean age of domino recipients at the time of transplantation was 58 years, 46 of them being men, and 15 being women. The median follow-up was 46 months. The overall 1-, 3-, and 5-year survival of domino recipients was 81.6%, 70.8% and 68.8%, respectively. Causes o…

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Sirolimus Use in Liver Transplant Recipients With Hepatocellular Carcinoma: A Randomized, Multicenter, Open-Label Phase 3 Trial

International audience; BACKGROUND:We investigated whether sirolimus-based immunosuppression improves outcomes in liver transplantation (LTx) candidates with hepatocellular carcinoma (HCC).METHODS:In a prospective-randomized open-label international trial, 525 LTx recipients with HCC initially receiving mammalian target of rapamycin inhibitor-free immunosuppression were randomized 4 to 6 weeks after transplantation into a group on mammalian target of rapamycin inhibitor-free immunosuppression (group A: 264 patients) or a group incorporating sirolimus (group B: 261). The primary endpoint was recurrence-free survival (RFS); intention-to-treat (ITT) analysis was conducted after 8 years. Overal…

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Multicentric evaluation of model for end-stage liver disease-based allocation and survival after liver transplantation in Germany - Limitations of the 'sickest first'-concept

Summary Since the introduction of model for end-stage liver disease (MELD) in 2006, post-orthotopic liver transplantation (OLT) survival in Germany has declined. The aim of this study was to evaluate risk factors and prognostic scores for outcome. All adult OLT recipients in seven German transplant centers after MELD implementation (December 2006–December 2007) were included. Recipient data were analyzed for their influence on 1-year outcome. A total of 462 patients (mean calculated MELD = 20.5, follow-up: 1 year) were transplanted for alcoholic cirrhosis (33.1%), hepatocellular carcinoma (26.6%), Hepatitis-C (17.1%), Hepatitis-B (9.5%), primary sclerosing cholangitis (5.6%) and late graft-…

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A prospective randomised, open-labeled, trial comparing sirolimus-containing versus mTOR-inhibitor-free immunosuppression in patients undergoing liver transplantation for hepatocellular carcinoma

Abstract Background The potential anti-cancer effects of mammalian target of rapamycin (mTOR) inhibitors are being intensively studied. To date, however, few randomised clinical trials (RCT) have been performed to demonstrate anti-neoplastic effects in the pure oncology setting, and at present, no oncology endpoint-directed RCT has been reported in the high-malignancy risk population of immunosuppressed transplant recipients. Interestingly, since mTOR inhibitors have both immunosuppressive and anti-cancer effects, they have the potential to simultaneously protect against immunologic graft loss and tumour development. Therefore, we designed a prospective RCT to determine if the mTOR inhibito…

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Activation pattern of signal transducers and activators of transcription (STAT) factors in inflammatory bowel diseases.

Cytokine signaling pathways involving transcription factors of the signal transducers and activators of transcription (STAT) family play a key role in the pathogenesis of inflammatory bowel diseases (IBD). STAT proteins are latent cytoplasmic transcription factors that induce transcription upon phosphorylation, dimerization, and nuclear translocation. However, their activation pattern in IBD is poorly understood. The aim of our study was to characterize STAT-expression in IBD.Mononuclear cells were isolated from 36 colonic specimens of Crohn's disease, ulcerative colitis, or from control patients. Cells were stimulated overnight with antibodies against human CD2 and CD28 and mononuclear cel…

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Management and outcomes after multiple corneal and solid organ transplantations from a donor infected with rabies virus

BACKGROUND: This article describes multiple transmissions of rabies via transplanted solid organ from a single infected donor. The empirical Milwaukee treatment regimen was used in the recipients. METHODS: Symptomatic patients were treated by deep sedation (ketamine, midazolam, and phenobarbital), ribavirin, interferon, and active and passive vaccination. Viral loads and antibodies were continuously monitored. RESULTS: Recipients of both cornea and liver transplants developed no symptoms. The recipient of the liver transplant had been vaccinated approximately 20 years before transplantation. Two recipients of kidney and lung transplants developed rabies and died within days of symptomatic d…

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Impact of antithrombin III on hepatic and intestinal microcirculation in experimental liver cirrhosis and bowel inflammation: An in vivo analysis

AIM: To analyze the hepatic and intestinal microcirculation in an animal model of liver cirrhosis and inflammatory bowel disease (IBD) and to characterize the anti-inflammatory action of antithrombin III (ATIII) on leukocyte kinetics and liver damage. METHODS: Hepatic and intestinal microcirculation was investigated by intravital videomicroscopy. Standardized models of experimental chronic liver cirrhosis and bowel inflammation were employed. Animals were divided into four groups (n = 6/group): controls, animals with cirrhosis, animals with cirrhosis and IBD, animals with cirrhosis and IBD treated with ATIII. RESULTS: Cirrhosis facilitated leukocyte rolling and sticking in hepatic sinusoids…

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