他克莫司对移植肝脏再灌注损伤的影响

目的 探讨他克莫司对移植肝脏再灌注损伤的影响.方法 建立大鼠肝移植模型,实验组(40只)和对照组(40只)分别注射他克莫司和生理盐水,检测再灌注24、48和96 h后TNF-α、IL-1、ALT、AST、LDH、内皮素(endothelin,ET)和丙二醛(malondialdehyde,MDA)水平,观察肝脏超微结构和细胞凋亡情况,RT-PCR法检测Fas、Bcl-2的mRNA水平.依据免疫抑制方案,将112例终末期肝硬化患者分为他克莫司组(63例)和环孢素A组(49例),比较临床肝移植使用环孢素A和他克莫司患者肝酶指标及急性排斥反应的发生.结果 实验组TNF-α、IL-1、ALT、AST、LDH、ET和MDA显著低于对照组(P＜0.05),肝脏超微结构受损和细胞凋亡较轻,Fas mRNA合成减少.患者使用他克莫司后急性排斥反应发生率较环孢素A低(x2=39.0,P＜0.05).结论 他克莫司可通过抑制细胞凋亡来减轻大鼠移植肝脏再灌注损伤,临床使用他克莫司能减少急性排斥反应的发生.     

Hepatic reperfusion injury following orthotopic liver transplantation in the rat

At 24 hr following orthotopic transplantation, rat liver grafts were perfused in situ for 7 min with trypan blue, a vital dye that provides information on hepatic microcirculation and stains nuclei of nonviable cells. Spotty and uneven dye distribution was observed indicating that hepatic microcirculation was disturbed 24 hr following transplantation surgery. Under these conditions, 15-20% of the hepatocytes were nonviable as assessed from trypan blue staining and frank necrosis. In contrast, perfusion of livers from untransplanted rats or liver explants exposed to cold ischemia for 60 min were judged normal by the criteria of uniform distribution of dye in the organ and absence of necrosis and nuclear dye uptake. Thus the observed damage was associated with reintroduction of blood and can therefore be classified as a reperfusion injury. The altered microcirculation and cell death following the operation was reduced markedly by perfusion of the cold, ischemic explant with nitrogen-saturated but not with oxygen-saturated buffer for 5 min prior to the implantation operation. Protection was even greater if the perfusion medium contained verapamil (20 micrograms/ml), a Ca++ channel blocker. We conclude that reperfusion of the stored liver causes an oxygen-dependent alteration in hepatic microcirculation that leads to hypoxia and scattered hepatocellular necrosis in the implanted graft. Brief perfusion of the hypoxic implant under anaerobic conditions may remove substrates involved in oxygen radical generation and prevent reperfusion injury upon introduction of oxygen into the graft via the blood. Taken together, these results suggest that removal of Euro-Collins' solution under anaerobic conditions may be beneficial clinically in preventing injury of surgical explants.     

Diffuse biliary tract injury after orthotopic liver transplantation.

An unusual type of diffuse biliary tract injury after liver transplantation that is characterized by multiple intrahepatic biliary strictures, ductal dilatations, fluid collections, or intrahepatic abscesses has been identified. Over a 5-year period, a total of 10 patients (2%) developed diffuse intrahepatic biliary injury with established vascular patency and no obvious source for their biliary tract pathology. All patients received livers preserved in University of Wisconsin solution with a mean preservation time of 16 hours. This biliary tract injury was associated with the presence of severe preservation injury and Roux limb biliary reconstruction. Of the 10 patients, 5 were treated nonoperatively with multiple stricture dilations and stent placements, 3 underwent retransplantation, 1 was treated operatively with hepaticojejunostomy, and 1 died of sepsis. This study suggests that this complication appears to be related to preservation injury and that the etiology may be ischemic in origin.     

Transcriptional changes in orthotopic liver transplantation and ischemia/reperfusion injury

BackgroundThere are few effective targeting strategies to reduce liver ischemia-reperfusion injury (IRI), which is one of the reasons for the poor prognosis of liver transplant recipients.MethodsA systematic approach combining gene expression with protein interaction (PPI) network was used to screen the characteristic genes and related biological functions of post-transplant. Differentially expressed genes (DEGs) between IRI+ and IRI- were identified. Logistic regression model and receiver operating characteristic (ROC) curve were used to identify potential target genes of IRI. The expression of key genes was verified by qRT-PCR and Western-blot experiments. Finally, the ssGSEA was used to identify the immune cell infiltration in patients with IRI.ResultsThe 283 common DEGs in GSE87487 and GSE151648 were mainly related to apoptosis and IL-17 signaling pathway. Through PPI network and logistic regression analysis, we identified that IL6, CCL2 and CXCL8 may be involved in the ischemia/reperfusion (IR) process. In addition, 32 genes were showed associated with IRI through inflammatory and metabolic pathways. Among the key genes identified, the differential expression of AGBL4, CILP2 and IL4I1 was verified by molecular experiments. Th17 cells of differentially infiltrated immune cells were positively correlated with CILP2 and IL4I1. The difference of Th17 cells between IRI+ and IRI- was verified by flow cytometry.ConclusionThe study showed that AGBL4, CILP2 and IL4I1 were associated with IRI. Th17 cells may be associated with the regulation of IRI by key genes. These genes and related pathways may be targets for improving IRI.     

Canine orthotopic liver transplantation

For the purpose of increasing long-term survival in canine orthotopic hepatic allotransplantation, immunosuppression by mizoribine and/or cyclosporin was instituted with the following results: 1) The survival of control dogs without treatment (n = 5) was 10.0 +/- 2.9 days (Mean +/- S.E.), and the survival of dogs treated with mizoribine (n = 15) was 44.6 +/- 31.8 days. There was no statistical difference between the two groups. On the other hand, the mean survival of dogs that were initially treated with cyclosporin and were then switched to mizoribine at one to three months after transplantation reached 145.4 +/- 70.8 days. The survival rate of dogs in the cyclosporin-mizoribine group was significantly greater than that of control group (p less than 0.02); and the survival rate of the former group proved also significantly better than that of the mizoribine group at 20 days after transplantation (X2, p less than 0.05); 2) in cases of acute rejection of the allograft, a gradual increase of the serum bilirubin level with a concomitant rise of S-GPT and alkaline phosphatase was generally observed. For an accurate diagnosis, however, an assessment of the biopsy findings of the allograft is important; 3) in chronic rejection, one animal developed the selective disappearance of interlobular bile ducts, often referred to as the "vanishing bile duct syndrome"; and 4) for differential diagnosis of vascular and/or biliary tract complications, specific morphological diagnostic procedures such as vascular and/or biliary tract angiographies are needed.     

丙酮酸乙酯预先给药对原位肝移植术大鼠肝损伤的影响

目的 评价丙酮酸乙酯预先给药对原位肝移植术大鼠肝损伤的影响.方法 成年健康雄性SD大鼠40只,体重220～ 250 g,作为肝移植术的供体和受体.采用随机数字表法,将受体大鼠随机分为3组(n=8):假手术组(S组)、肝移植组(LT组)和丙酮酸乙酯组(EP组).S组仅行单纯开关腹手术,LT组和EP组分别采用二袖套法建立大鼠原位肝移植模型,EP组于切皮前1h时尾静脉注射丙酮酸乙酯40 mg/kg.于新肝期2h时采集静脉血样,检测血清ALT和AST的活性;取肝中叶组织检测MDA含量和SOD活性.结果 与S组比较,LT组和EP组血清ALT、AST的活性和肝组织MDA含量升高,SOD活性降低(P＜0.05或0.01);与LT组比较,EP组血清ALT、AST的活性和肝组织MDA含量降低,SOD活性升高(P＜0.05或0.01).结论 丙酮酸乙酯预先给药可减轻原位肝移植术大鼠肝损伤.     

脂微球化前列地尔对原位肝移植术患者肺损伤的影响

目的 评价脂微球化前列地尔对原位肝移植术患者肺损伤的影响.方法 选择择期原位肝移植术患者48例,年龄45 ～ 64岁,ASA分级Ⅱ-Ⅳ级,体重45 ～ 70 kg,性别不限,采用随机数字表法,将其分为2组(n=24):对照组(C组)和脂微球化前列地尔组(A组).A组分别于麻醉诱导前和新肝期1h时缓慢静脉输注(输注时间30 min)脂微球化前列地尔5μg(生理盐水稀释至10 ml);C组术中未使用脂微球化前列地尔.于术前即刻(T1)、术毕(T2)、术后24 h(T3)时记录气道峰压(PIP)、平均气道压(Pmean)、肺动态顺应性(Cd)、氧合指数(OI)、呼吸指数(RI)、呼出气冷凝液中炎性因子的浓度.记录术后7d内肺部并发症的发生情况.结果 与C组比较,A组T2.3时PIP、Pmean、RI、呼出气冷凝液中TNF-α、IL-8浓度均降低,Cd和OI升高,术后7d内急性肺损伤和肺部感染发生率降低(P＜0.05),其余指标差异无统计学意义(P＞0.05).结论 脂微球化前列地尔对原位肝移植术患者具有肺保护作用.     

Hepatocellular ultrastructure after ischemia/reperfusion injury in human orthotopic liver transplantation

The number of patients requiring organ transplants still outpaces the number of available transplantable organs. During the process of orthotopic liver transplantation (OLTx), donor organs undergo significant stress resulting from ischemia and reperfusion. Healthy organs respond to this stressful environment with compensatory mechanisms that ideally allow for complete recovery. However, "marginal" organs do not compensate as well. Hepatic steatosis typically renders an organ nontransplantable; a liver with 30% or more fat has a 25% chance of primary nonfunction (PNF) or graft failure after a technically sound operation. In this study, we report on the significant markers of cellular ultrastructural change in steatotic livers. These include glycogen content, mitochondrial swelling, and hepatocellular blebbing. The data disclosed here argue that further investigation of these factors in marginal organs subjected to I/R may better facilitate our understanding of PNF.     

Cytomegalovirus infection in orthotopic liver transplantation

We retrospectively studied 175 orthotopic liver transplants in 151 patients. Of the 151 patients, 59 (39.1%) were diagnosed as having cytomegalovirus (CMV) infection. The rate of infection in patients treated for rejection was 48.8% as compared to 26.2% in patients without rejection (P less than 0.01). Antirejection therapy was associated with culture-positive cases in 33 out of 43 patients as compared to 9 out of 16 patients who had CMV antibody titer elevations. Patients were treated with gancyclovir if they had simultaneous positive cultures from multiple sites and were seriously ill. Eighteen of the 19 patients thus treated had side effects, one of which was serious (bone marrow hypoplasia). Cultures became negative in 15 out of 17 (88%) of the surviving patients. Patient survival was similar to our overall survival rate of 87%.     

小鼠原位肝移植模型的建立

目的 建立稳定的小鼠原位肝移植模型。方法 采用对端吻合重建肝上下腔静脉，“双袖套法”重建门静脉和肝下下腔静脉。支架法重建胆管。结果 共施行50例小鼠原位肝移植，术后24h存活率92％（46／50），1周存活率84％（42／50），2周存活率80％（40／50）。结论 本实验中小鼠原位肝移植存活率较高，稳定可靠，易于标准化，是一种研究移植免疫的理想的动物模型。     

原位肝移植的静脉-静脉转流

目的评价体外静脉-静脉转流技术对原位肝移植术中无肝期血流动力学、生化、体温和肾功能的影响。方法28例原位肝移植术中使用JostraRotaFlow离心泵、热交换器、边缘肝素化进行开放式静脉-静脉转流。结果体外静脉-静脉转流时间（136.7±60.4）min,灌注流量0.5～3.5L/min,动脉压维持在（82.3±3.3）mmHg,中心静脉压维持在（8.12±4.05）cmH     

原位肝移植的临床探讨

本文报告１１９例１３５次的位肝移植的临床试验。其术后早期肝植体功能障碍诊断至关重要。移植后中心问题是排斥反应。临床表现、实验参数、特殊检查和组织学检查等可客观地评价移植后肝功能障碍，并可排斥反应，提高移植后治疗效果。     

Mortality after orthotopic liver transplantation

An analysis was made of the causes of death in 22 of 50 patients receiving consecutive orthotopic liver transplants. A close look at the fatal course of these patients revealed three major patterns: surgical complications (27%), pathology of the hepatic artery anastomosis (23%), and cholestasis (32%). Technical factors were the major reasons for excessive peroperative blood loss, and not the coagulopathy accompanying the liver disease. The etiology of hepatic artery thrombosis is not known. It leads to irreversible damage of the graft, causing death due to acute hepatic failure or to cholangitis and sepsis. The only way to treat patients with this complication is retransplantation. Several factors can induce cholestasis. Retrospectively, it appears that this was mostly due to inappropriate immunosuppression, often a result of the difficult differential diagnosis between rejection and viral infection. Recognition of these three basic patterns should enable us to anticipate their subsequent complications. This may lead to a reduction in morbidity and mortality after liver transplantation.     

Bile cytology in orthotopic liver transplantation

The utility of bile cytology (BC) in the diagnosis of hepatic graft rejection was assessed in 21 liver transplantations in 18 patients. A total of 307 BC specimens were studied; cell density and relative contribution of different cell types were monitored in 130 specimens. The findings in 62 fine-needle aspiration biopsies and 9 core needle biopsies (CNB) from the transplants were compared with those of the BC specimens. For the first 3-5 days after transplantation, BC specimens were cell-rich, containing degenerating cells and polymorphonuclear leukocytes. In uneventful cases, the cellularity of the specimens gradually decreased. Upon rejection, the number of cells increased, with a high percentage of PMN. Occasionally, blasts or macrophages were detected. After antirejection treatment, the cellularity of the specimens decreased. The analysis of the relationship between the findings of BC and FNAB showed that a high cell density was indicative of rejection. However, BC was not as sensitive to rejection as was FNAB. No clear-cut correlation was found between BC pattern and the degree of cell infiltration in portal triads as seen in CNB specimens. Our results indicate that serial bile cytology is valuable as an additional diagnostic method in monitoring hepatic graft rejection.     

Cytomegalovirus infection in orthotopic liver transplantation

Abstract. We retrospectively studied 175 orthotopic liver transplants in 151 patients. Of the 151 patients, 59 (39. 1%) were diagnosed as having cytomegalovirus (CMV) infection. The rate of infection in patients treated for rejection was 48. 8% as compared to 26. 2% in patients without rejection ( P < 0. 01). Antirejection therapy was associated with culture-positive cases in 33 out of 43 patients as compared to 9 out of 16 patients who had CMV antibody titer elevations. Patients were treated with gancyclovir if they had simultaneous positive cultures from multiple sites and were seriously ill. Eighteen of the 19 patients thus treated had side effects, one of which was serious (bone marrow hypoplasia). Cultures became negative in 15 out of 17 (88%) of the surviving patients. Patient survival was similar to our overall survival rate of 87%.