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In recent years, the cross talk between the liver and the immune system is being uncovered, in part by studying liver involvement in primary immune deficiencies (PID) and in part by investigating the alterations of the immune system following orthotopic liver transplantation (OLT). Here we review some of the reciprocal interactions between the liver and the immune system. Patients with PID, particularly those involving inherited defects in T and B cells or innate immunity are prone to infections and inflammatory responses that often involve the liver. Omenn's syndrome, familial hemophagocytic lymphohistiocytosis, AIRE, FOXP3 and CD25 deficiencies, common variable immunodeficiency, CD40 ligand deficiency, chronic granulomatous disease and autoimmune lymphoproliferative syndrome are some of the notable PID associated with typical hepatobiliary abnormalities. Knowledge gained from studying these PID together with laboratory and histological evaluations can assist in managing PID-associated liver dysfunction. The liver itself also has important effects on the immune system, as evident from the growing experience with patients surviving OLT. Up to 40% of pediatric patients who receive OLT suffer from post transplantation allergy, autoimmunity, and immune-mediated disorders (PTAA). PTAA is more common after liver and heart transplantations than kidney transplantations. Potential contributing factors for the increased frequency of PTAA after OLT include the age of the patients, the prolonged use of tacrolimus and the reduced regulatory immune function with a shift towards a TH2 immune response. Better understanding of the mechanisms leading to the development of PTAA after OLT will also improve the management of these conditions.  相似文献   
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Gastric cancer, one of the most common disease, has become a major public health problem worldwide. Cisplatin (DDP) has been a widely used drug for the treatment of cancer, also usually applied in gastric cancer in clinic. However, the side effects including toxicity and drug-resistance restricted the usage of DDP in clinic, so we prepared a DDP-complexed hydrogel (DDP-Gel) and investigated its efficacy in gastric cancer. For in vivo studies, MKN45-Luc cells were injected into BLAB/C node mice subcutaneously to establish gastric cancer with orthotopically grown tumors. Mice bearing tumors were treated with normal saline, DDP and DDP-Gel. Body weight and survival condition were observed and recorded. The treatment efficacy in vivo was detected by luciferase imaging and histological evaluation was performed by H&E staining of different organs. Additionally, normal ICR mice were treated with different doses of DDP/DDP-Gel to calculate their LD50 in vivo. The results showed that DDP-Gel prolonged survival time and ameliorated body weight changes of mice bearing tumors. DDP-Gel exhibited higher efficacy to inhibit tumor growth and metastasis, compared to DDP. Besides, LD50 of DDP-Gel was 166.0?mg/kg, 13.2 folds higher than DDP. As a conclusion, DDP-Gel showed a more effective and safer function than DDP in gastric cancer, which indicating that DDP-Gel might be a novel strategy for gastric cancer therapy.  相似文献   
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Hypoxia-inducible factor 1α (HIF1α) has emerged as a promising new target for pancreatic cancer treatment over the past decade. High expression of HIF-1α increases the drug resistance of the current first line chemotherapeutic drug, gemcitabine (Gem). Here we employed biocompatible lipid-polymer hybrid nanoparticles to co-deliver HIF1α siRNA (si-HIF1α) and Gem for pancreatic cancer treatment in subcutaneous and orthotopic tumor models. The cationic ε-polylysine co-polymer (ENPs) can effectively absorb negatively charged si-HIF1α on the surface and encapsulate Gem to the hydrophilic core. Further coating of ENPs with PEGylated lipid bilayer resulted formation of LENPs, with reversed surface charge. The lipid bilayer of LENPs prevented nanoparticle aggregation and si-HIF1α degradation in serum, as well as Gem leakage. Those characteristics endow LENPs encapsulating drug prolonged lifetime in bloodstream and improved drug release via the enhanced tumor vasculature effect in tumor tissues. LENPs can co-deliver Gem and si-HIF1α (LENP-Gem-si-HIF1α) into tumor cells and effectively suppress the HIF1α expression both in vitro and in vivo. LENP-Gem-siHIF1α exhibited significant synergistic antitumor effects. Furthermore, LENP-Gem-si-HIF1α showed excellent capability to inhibit tumor metastasis in orthotopic tumor model.  相似文献   
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Early microbial recognition by the innate immune system is accomplished by Toll-like receptors (TLRs), with resultant initiation of a pro-inflammatory response against infecting organisms. In spite of presence of an abundance of Toll-like receptors on the surface of the liver, gut bacteria does not elicit an inflammatory reaction in healthy individuals due to tolerance to these TLRs, suggesting that the inflammatory responses seen in the liver are the result of breakdown of this tolerance. While orthotopic liver transplantation is often life saving in many instances, death following this procedure is most commonly due to infection that occurs in up to 80% of transplant recipients, most commonly due to microbial causes in up to 70% of cases and viral infections in 20%, while fungal infections affect only 8% of cases. The probability of acquiring infection following hepatic transplantation is heightened due to affection of the innate immune defense mechanisms of the host following this procedure. Single nucleotide polymorphisms of TLRs have been associated with increased likelihood of either development of post-transplant infection or eradication of infecting organism. However, conflicting reports from other studies reveal that prevalence of this single nucleotide polymorphism is not increased in infected patients.  相似文献   
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ObjectiveThis study sought to evaluate the effectiveness of diltiazem at achieving a targeted heart rate (HR) of ≤75 bpm in orthotopic heart transplant patients during coronary computed tomography (CT) angiography.MethodsBaseline heart rates were compared to heart rates after diltiazem administration in 25 adult orthotopic heart transplant subjects being monitored by electrocardiogram (ECG) gaiting on a multidetector CT scanner.ResultsThe mean baseline HR of the group was 84.28 ± 11.305 bpm. After diltiazem administration, the mean heart rate of the group at the time of the coronary CT angiography study was 75.32 ± 9.49 bpm. Heart rates decreased in 23 subjects (92%) and the targeted heart rate of ≤75 bpm was observed in 13 subjects (52%).ConclusionDiltiazem administration was associated with a decrease in heart rate, yet reaching the targeted heart rate was limited. Further study regarding diltiazem dosing and its impact is warranted.  相似文献   
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Fulminant myocarditis has been defined as the clinical manifestation of cardiac inflammation with rapid-onset heart failure and cardiogenic shock. We report on the case of a 23-yr-old woman with pathology-proven fulminant lymphocytic myocarditis presenting shock with elevated cardiac troponin I and ST segments in V1-2, following sustained ventricular tachycardia and a complete atrioventricular block. About 55 min of intensive cardio-pulmonary resuscitation, with extracorporeal membrane oxygenation support, bridged the patient to orthotopic heart transplantation. The explanted heart revealed diffuse lymphocytic infiltration and myocyte necrosis in all four cardiac chamber walls. Aggressive mechanical circulatory support may be an essential bridge for recovery or even transplantation in patients with fulminant myocarditis with shock.

Graphical Abstract

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9.
目的 建立中国人同一起源肿瘤不同恶性潜能前列腺癌动物模型,为研究前列腺癌转移进展机制及激素抵抗的发生机制提供理想的动物模型.方法 采用组织块外科原位移植法将人前列腺癌组织分别移植到虚拟去势组及去势组雄性裸小鼠前列腺部,成瘤后进行鼠间传代移植,选取虚拟去势组原位移植瘤、移植淋巴结转移瘤、去势组第4代淋巴结转移瘤体外培养建立细胞系,应用Boyden Chamber细胞运动实验检测细胞迁徙转移能力,描绘细胞生长曲线分析细胞增殖及激素依赖性,裸小鼠皮下异种移植瘤模型检测成瘤率、肿瘤湿重及浸润范围验证不同代移植瘤细胞在裸小鼠异种移植的生长状态.结果 第1代虚拟去势组成瘤率30%,无淋巴结转移,取移植瘤反复原位传代移植第3代成瘤率50%,盆腔淋巴结转移率40%.去势组原代移植以及来自虚拟去势组的原位移植瘤反复原位移植均未见移植瘤,源自虚拟去势组淋巴结转移瘤组织反复原位传代移植至第4代,成瘤率33%,其中一只可见盆腔淋巴结转移.三种细胞系细胞生长、迁徙以及体外裸小鼠成瘤率均有显著差别(P<0.05).结论 裸小鼠前列腺癌原位移植反复传代可增强肿瘤成瘤率、转移力等恶性指标.以裸小鼠淋巴结转移瘤接种去势裸小鼠可筛选出激素非依赖性异种移植瘤及转移瘤.  相似文献   
10.
Hepatitis E virus(HEV) is an emerging pathogen and an increasingly recognized cause of graft hepatitis, especially in the post-orthotopic liver transplantation immunocompromised population. The exact incidence and prevalence of HEV infection in this population remains unclear but is certainly greater than historical estimates. Identifying acute HEV infection in this population is imperative for choosing the right course of management as it is very difficult to distinguish histologically from acute rejection on liver biopsy. Current suggested approach to manage acute HEV involves modifying immunosuppression, especially discontinuing calcineurin inhibitors which are the preferred immunosuppressive agents post-orthotopic liver transplantation. The addition of ribavirin monotherapy has shown promising success rates in clearing HEV infection and is used commonly in reported cases.  相似文献   
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