胰腺移植后细胞凋亡及Bax/Bcl-2表达的实验研究

胰腺移植后腺泡细胞凋亡是缺血再灌注损伤等造成移植胰腺失功的主要原因。2001～2003年，我们通过建立稳定的大鼠胰腺移植模型，观察了移植胰腺早期冷缺血再灌注损伤时细胞凋亡的变化以及Bax／Bcl-2的表达，现报告如下。     

Fas/FasL系统与心肌缺血再灌注细胞凋亡

心肌缺血再灌注损伤与众多凋亡基因密切相关.Fas/FasL系统在心肌缺血再灌注损伤中起关键作用,是引起细胞凋亡的主要途径之一,是直接启动细胞凋亡信号传导的系统之一.Fas/FasL系统与心肌缺血再灌注细胞凋亡及其信号传导机制是目前国内外研究的热点,现对该问题做一综述.     

糖尿病脑缺血再灌注大鼠海马CA1区Fas蛋白表达及细胞凋亡的研究

目的观察Fas蛋白在糖尿病脑缺血再灌注大鼠海马CA1区神经元损伤中的表达。方法采用链脲佐菌素(STZ)诱导和线栓法制备糖尿病大脑中动脉闭塞模型(MCAO),应用免疫组化方法和流式细胞术观察糖尿病脑缺血再灌注组与缺血再灌注组海马CA1区Fas表达变化和细胞凋亡情况。结果缺血再灌注组及糖尿病脑缺血再灌注组大鼠海马CA1区Fas阳性染色阳性细胞分别为(21·3±3·1)个/100μm、(51·9±4·2)个/100μm,较正常对照组〔(1·1±1·7)个/100μm〕及假手术组〔(10·3±2·4)个/100μm〕增多(P<0·05);而糖尿病脑缺血再灌注组比缺血再灌注组增加得更明显(P<0·05);糖尿病脑缺血再灌注组海马CA1区Fas蛋白表达上调,细胞凋亡百分数〔(29·34±8·45)%〕明显高于缺血再灌注组〔(17·59±6·38)%〕(P<0·05)。结论糖尿病大鼠脑缺血再灌注损伤后海马细胞发生凋亡,Fas介导的细胞凋亡机制可能是糖尿病加重脑缺血再灌注海马神经元损伤机制之一。     

胰腺组织缺血再灌注损伤后ICAM-1表达的实验研究

缺血再灌注损伤(ischemic reperfusion，I／R)在临床上非常常见．目前认为细胞间粘附分子-1(intercellular adhesion molecule-1，ICAM-1)是参与许多器官I／R的重要物质之一，不同器官血管壁促凝的表现型不同一．ICAM-1在胰腺组织中的表达情况在不同药物诱导的急性胰腺炎动物模型中亦不一致。近年来．我们采用免疫组化ABC法研究胰腺I／R时的ICAM-1表达情况．现报告如下。     

微量去甲肾上腺素预处理对缺血再灌注大鼠心肌细胞凋亡及相关蛋白表达的影响

本实验复制缺血再灌注模型 ,应用微量去甲肾上腺素(ｎｏｒｅｐｉｎｅｐｈｒｉｎｅ ,ＮＥ)预处理 (ｐｒｅｃｏｎｄｉｔｉｏｎｉｎｇ ) ,观察缺血再灌注 (ｉｓｃｈｅｍｉａ ｒｅｐｅｒｆｕｓｉｏｎ ,Ｉ Ｒ)大鼠心肌细胞凋亡及Ｂｃｌ 2、Ｂａｘ基因表达情况 ,以探讨ＮＥ预处理防治     

缺血预处理对移植肝缺血再灌注损伤中细胞凋亡的影响

目的 探讨细胞凋亡在移植肝缺血再灌注损伤中的作用及缺血预处理对其影响。方法 通过对移植肝进行 因预处理,用全自动生化分析仪检测肝功能、比色法测定移植肝组织的ＭＤＡ、用流式细胞仪结合原位标记技术检测细胞调７亡。结果 移植肝再灌注后血中ＡＳＴ、ＡＬＴ、ＬＤＨ和肝组织中ＭＤＡ均明显升亮,肝细胞调亡明显增加,经缺血预处理后,血中ＡＳＴ,ＡＬＴ,ＬＤＨ和肝组织中ＭＤＡ均降低,肝细胞调亡亦明显减少,结论 缺血     

异丙肾上腺素预处理对大鼠胰腺移植后缺血再灌注损伤的抑制作用

目的:探讨减轻大鼠胰腺移植后缺血再灌注损伤的保护作用机制.方法:IPC后动态检测大鼠胰腺组织热休克蛋白表达.建立大鼠胰腺移植缺血再灌注模型,选择表达热休克蛋白高峰时段供体大鼠胰腺移植作为实验组,未预处理供体大鼠胰腺移植作为对照组.移植后6 h,采集静脉血及移植胰腺.热休克蛋白70(HSP70)分别用Western blot法及免疫组织化学法检测.免疫组织化学法测定肿瘤坏死因子-α(TNF-α)表达.流式细胞仪检测胰腺细胞凋亡率.碘淀粉比色法检测血淀粉酶水平.结果:IPC后供体大鼠胰腺中HSP70的表达在24 h达到高峰,与其他各时段比较具有显著差异(0.92±0.25 vs 0.24±0.04,0.34±0.06,0.58±0.07,0.62±0.11,0.25±0.09,均P<0.05),IPC后6 h,12 h,24 h,36 h大鼠胰腺中HSP70的表达与未预处理组相应时段比较差异也显著(0.34±0.06 vs 0.28±0.07,0.58±0.07 vs 0.25±0.04.0.92±0.25 vs 0.27±0.05,0.62±0.11vs 0.25±0.06,均P<0.05),48 h恢复到原来水平.而未预处理组各时段间比较差异无统计学意义(P>0.05).HSP70主要表达于胰腺腺泡细胞及血管壁.对照组胰腺组织中TNF-α、细胞凋亡率、中性粒细胞、血淀粉酶的水平明显升高,与假手术组相比差异显著(均P<0.01).实验组降低了胰腺组织中TNF-α、细胞凋亡率、白细胞数、血淀粉酶的水平,与对照组比较差异具有统计学意义(11 929±1220vs46 111±3127,26.7%±4.5%vs 37.4%±4.7%,3 308±531 vs 6668±1506,1057 IU/L±148IU/L vs 1 408 IU/L±195IU/L,均P<0.05).结论:IPC减轻了大鼠胰腺移植后缺血再灌注损伤,IPC保护作用与HSP70的诱导生成有关.     

同种异体猪胰腺移植后的细胞凋亡形态学观察

目的观察胰腺移植后胰腺细胞凋亡的形态学变化。方法以6对动物猪作为实验对象，配对行胰肾联合移植（SPK），观察术后移植物细胞凋亡的形态。结果电镜检查标本可见胰腺细胞出现凋亡，观察到凋亡小体和核固缩现象，TUNEL法标记可观察到大量的凋亡细胞。结论胰腺移植早期可观察到胰腺细胞凋亡现象。     

急性肾缺血再灌注损伤氧化侵袭与细胞凋亡

目的探讨急性肾缺血再灌注损伤过程氧化侵袭与肾细胞凋亡在肾损伤发生机制中的作用。方法采用摘除大鼠左肾,钳夹右侧肾蒂的方法,制成急性缺血再灌注肾损伤模型,测定GSHPx、SOD活性和MDA含量及检测肾细胞凋亡率。结果缺血再灌注不同时期肾组织SOD活力水平降低,与对照组相比差异显著(P<0.05,P<0.01),MDA含量高于对照组(P<0.05),GSHPx在再灌注早期活力减弱,明显低于对照组(P<0.01),晚期活力基本恢复;肾细胞凋亡率与对照组相比差异显著(P<0.05、P<0.01);抗氧化酶SOD活力与细胞凋亡率负相关,MDA含量与细胞凋亡率正相关。结论缺血再灌注不同时期肾组织氧化侵袭在肾损伤病理过程中起重要作用;再灌注损伤与氧化侵袭和细胞凋亡有关。     

大鼠心肌缺血/再灌注损伤心肌细胞凋亡与Fas、FasL基因表达的变化

目的：探讨大鼠实验性心肌缺血再灌注时心肌细胞凋亡与Fas及Fas蛋白配体（Fas Ligand,FasL）基因表达的变化及与心肌组织损伤的关系。方法：以穿线结扎或松扎左冠状动脉制备大鼠心肌缺血再灌注模型。64只大鼠随机分成假手术组（假手术24h）、缺血再灌注I组（缺血30min、再灌注24h）、缺血再灌注Ⅱ组（缺备30min、再灌注72h）及缺血再灌注Ⅲ组（缺血3h、再灌注24h）。以缺口末端标记法检测心肌细胞凋亡的变化,S－P免疫组化法分别检测Fas与FasL蛋白水平变化,采用逆转录聚合酶链反应法检测Fas基因mRNA的表达改变,并分析心肌组织病理学损伤程度。结果：心肌缺血再灌注后心肌细胞凋亡指数Fas蛋白阳性染色指数与炎性细胞FasL蛋白阳性染色指数均增加,且均随缺血或再灌注时间延长而进一步增高; Fas基因的mRNA表达也上调,但以再灌注24h时达高峰;心肌缺血再灌注后心肌组织呈大小不一的灶性坏死,坏死周围有爆炸性一细胞浸润。结论：心肌缺血再灌注时心肌细胞凋亡、Fas基因的蛋白与mRNA表达水平及炎性细胞的FasL蛋白表达量均增加,心肌细胞凋亡与Fas/FasL系统参与了心肌缺血再灌注损伤过程。     

胰腺移植术后并发症及其防治

随着器官保存技术发展,手术方式的改进,新型免疫抑制药物的应用以及术后监护的重视,胰腺移植技术现已日臻完善,成为治疗糖尿病并发尿毒症的理想方法.据国际胰腺移植登记中心(international pancreas transplant registry,IPTR)最新统计,从1966年胰腺移植首次开展到2008年末,全球报道的胰腺移植已超30000例,其中有22000多例在美国实施[1].而其并发症自从1966年首例胰肾联合移植患者在术后2mo后死于排斥反应和败血症,就与胰腺移植有着密不可分的联系,随着胰腺移植的广泛开展,有必要让更多人对其并发症也有更进一步的了解,本文就从胰腺移植并发症的预防和治疗展开综述.     

Postabsorptive muscle protein metabolism in type 1 diabetic patients after pancreas transplantation

Insulin was shown to induce protein anabolism in vivo mainly by inhibiting proteolysis. Heterotopic pancreas transplantation in type 1 diabetes mellitus is characterized by peripheral hyperinsulinemia due to systemic rather than portal insulin delivery. Therefore, we studied the postabsorptive muscle protein metabolism in type 1 diabetic patients with or without pancreas transplantation. The forearm balance technique was performed in 9 type 1 diabetic patients on exogenous insulin treatment, in 4 type 1 diabetic patients following successful pancreas transplantation and in 6 healthy volunteers. Labelled leucine and phenylalanine were infused to quantify whole-body and muscle protein synthesis, respectively. In the postabsorptive state, whole-body protein synthesis (leucine kinetics) was similar in pancreas-transplanted patients and controls. In contrast, muscle protein synthesis tended to be less negative in pancreas-transplanted patients with respect to type 1 diabetic patients and healthy volunteers. The present data suggest that recipients with peripheral insulin delivery and chronic hyperinsulinemia are characterized by a preferential stimulation of protein synthesis in muscle rather than in the splanchnic district. When insulin was infused acutely, while maintaining euglycemia, the whole-body and muscle protein synthesis rates were approximately halved in type 1 diabetic patients with and without pancreas transplantation. We conclude that pancreas transplantation is able to normalize basal and insulin-stimulated protein metabolism. Chronic hyperinsulinemia counteract steroid-induced protein degradation by means of a mild, but persistent stimulation of muscle protein synthesis. Accepted in revised form: 1 March 2001     

Two-layer cold storage method for pancreas and islet cell transplantation

The two-layer cold storage method (TLM) was f irst reported in 1988, consisting of a perfluorochemical (PFC) and initially Euro-Collins' solution, which was later replaced by University of Wisconsin solution (UW). PFC is a biologically inert liquid and acts as an oxygen-supplying agent. A pancreas preserved using the TLM is oxygenated through the PFC and substrates are supplied by the UW solution. This allows the pancreas preserved using the TLM to generate adenosine triphosphate during storage, prolonging ...     

A steady decline in pancreas transplantation rates

Background/objectives

After years of growth in many pancreas transplant programs, UNOS has reported declining transplant numbers in the USA. This precipitating trend urges for an evaluation of the transplant numbers and scientific productivity in the Eurotransplant region and the UK.

Mono-oligoclonal immunoglobulin abnormalities in diabetic patients after kidney transplantation: influence of simultaneous pancreas graft

Summary Monoclonal components (MC) are detected in as high as 30 % of renal transplant recipients. Our aim was to evaluate the incidence, relevance and consequence of monoclonal components in patients with Type I (insulin-dependent) diabetes who received kidney (n = 22), kidney and whole pancreas (n = 41), kidney and segmental pancreas (n = 24) and kidney and islets (n = 12) transplants. Immunosuppression was based on prophylactic anti-lymphocyte globulins, corticosteroids, azathioprine and cyclosporin in all patients; acute rejection was treated with steroids or anti-lymphocyte monoclonal immunoglobulin therapy (OKT3) or both. Serum immunofixation was carried out in all patients before transplantation and then after at 6 months and then yearly. Monoclonal components were detected in 81 of 99 patients (82 %); 52 patients (52 %) developed them within 6 months of transplantation, 15 (15 %) between 6 and 12 months, with a peak prevalence at 1 year post-transplant (58 %) and a decrease thereafter (10 % at 9 years). Kidney recipients showed a lower incidence of monoclonal components when compared with those who received kidneys and segmental pancreases and those who received kidneys and whole pancreases. Monoclonal components were more often detected in patients who had previously experienced an acute renal rejection. Cytomegalovirus infection and acute rejection occurring in the same patient further increased the risk of developing monoclonal components, the development of which did not correlate with OKT3 treatment. A Post-transplant lymphoproliferative disorder was developed by two patients (2 %), one with 5 and the other with 6 monoclonal components. In conclusion, diabetic patients receiving kidney and/or Pancreas transplantation, experiencing both cytomegalovirus infection and acute rejection, are at greatest risk of developing monoclonal components but they appear to be benign and transient; multiple band detection is a marker for the subsequent development of post-transplant lymphoprolifertive disorder. [Diabetologia (1998) 41: 1176–1179] Received: 5 January 1998 and in revised form: 28 April 1998     

High incidence of carpal tunnel syndrome in diabetic patients after combined pancreas and kidney transplantation

Fifty-eight patients with long-standing type 1 (insulin-dependent) diabetes were studied prospectively after combined pancreas and kidney transplantation for a mean observation period of 47.9 months (range 17–116 months). Thirty-three per cent of these patients (19/58) developed carpal tunnel syndrome after a mean interval of 1.7 years (range 3 months–5 years). This rate is about twice that in type 1 diabetic patients. The manifestation of carpal tunnel syndrome was not significantly associated with worsening of diabetic polyneuropathy or with deterioration of kidney or pancreas function. In all but one patient symptoms improved without surgical intervention. This study suggests that patients after combined pancreas and kidney transplantation have an increased risk of carpal tunnel syndrome for which the etiology and pathophysiology are unknown. In most patients no surgical intervention is necessary.     

Long-term follow-up of glycaemic control and parameters of lipid transport after pancreas transplantation

We report the long-term metabolic observations made on 37 patients after simultaneous pancreas and kidney transplantation. Plasma C-peptide levels were above the physiological range in all patients and there was no significant difference between patients undergoing delayed duct occlusion (n=12) or those with drainage of exocrine secretion into the urinary bladder (n=25). HbA_1c was equally at the upper end of the normal range in both subsets of patients. Mean fasting cholesterol (237 mg/dl) and triglycerides (122 mg/dl) were normal, and HDL-cholesterol was above normal with an average concentration of 77 mg/dl. Two patients underwent an oral fat tolerance test and showed extremely low postprandial lipaemia and very high lipoprotein lipase activities. We conclude that patients with a functioning pancreas graft persistently demonstrate normoglycaemia, elevated C-peptide, and a very favourable lipid profile both in the fasting and the postprandial state.     

胰腺移植的研究进展

胰腺移植是治疗终末期糖尿病的可行性选择.40来,外科手术技术及免疫抑制的进步,显著促进了胰腺移植适应证的增加和移植物存活率的提高.胰腺移植能替代患者每天的胰岛素注射,提高生活质量,同时也需要复杂的手术操作和终生的免疫抑制治疗.因此发展创伤更小的内分泌替代治疗方法(胰岛移植)的研究一直在进行.本文概括地介绍了胰腺移植的适...