The Effects of Cyclooxygenase (COX)-2 Inhibition on Ischemia-Reperfusion Injury in Liver Transplantation

Purpose: Our objective was to evaluate whether COX-2 inhibition with FK3311, a selective cyclooxygenase (COX)-2 inhibitor, improves transplanted liver function. Methods: Inbred male Lewis rats weighing 200–260 g were used. The donor liver was perfused with cold University of Wisconsin (UW) solution and then stored in the same solution at 4°C for 18 hr. After the preservation period, orthotopic liver transplantation was performed. Animals were divided into three groups: the control group; the FK low-dose group (1 mg/kg FK3311 i.v. 20 min before reperfusion); and the FK high-dose group (3 mg/kg FK3311 i.v. 20 min before reperfusion). Survival rate, serum GOT and GPT levels, liver tissue blood flow, and serum thromboxane B₂ (TxB₂) levels were compared among groups. Results: Survival rate was significantly better (p <. 05) and serum GOT levels 30 min after reperfusion were significantly lower (p <. 05) in the FK high-dose group compared to the other two groups. Four hours after reperfusion, GPT levels and liver tissue flow were significantly (p <. 05) better in the FK high-dose group compared to the control. Both 30 min and 4 hr after reperfusion, serum TxB₂ levels were significantly lower in the FK high-dose group compared to the control (p <. 05). Conclusion: COX-2 activity results in deteriorated liver function after I/R injury associated with transplantation, and selective COX-2 inhibition improved liver graft function.     

Hypothermic continuous machine perfusion improves metabolic preservation and functional recovery in heart grafts

The number of heart transplants is decreasing due to organ shortage, yet the donor pool could be enlarged by improving graft preservation. Hypothermic machine perfusion (MP) has been shown to improve kidney, liver, or lung graft preservation. Sixteen pig hearts were recovered following cardioplegia and randomized to two different groups of 4‐hour preservation using either static cold storage (CS) or MP (Modified LifePort© System, Organ Recovery Systems©, Itasca, Il). The grafts then underwent reperfusion on a Langendorff for 60 min. Energetic metabolism was quantified at baseline, postpreservation, and postreperfusion by measuring lactate and high‐energy phosphates. The contractility index (CI) was assessed both in vivo prior to cardioplegia and during reperfusion. Following reperfusion, the hearts preserved using CS exhibited higher lactate levels (56.63 ± 23.57 vs. 11.25 ± 3.92 μmol/g; P < 0.001), increased adenosine monophosphate/adenosine triphosphate (AMP/ATP) ratio (0.4 ± 0.23 vs. 0.04 ± 0.04; P < 0.001), and lower phosphocreatine/creatine (PCr/Cr) ratio (33.5 ± 12.6 vs. 55.3 ± 5.8; P <0.001). Coronary flow was similar in both groups during reperfusion (107 ± 9 vs. 125 + /‐9 ml/100 g/min heart; P = ns). CI decreased in the CS group, yet being well‐preserved in the MP group. Compared with CS, MP resulted in improved preservation of the energy state and more successful functional recovery of heart graft.     

Intermittent capillary perfusion in rat pancreas grafts following short- and long-term preservation in University of Wisconsin solution

In pancreas transplantation (PTx), ischemia/reperfusion-induced deterioration of graft-microcirculation is accompanied by alterations of intermittent capillary perfusion (IP; alternating cessation and resumption of capillary blood flow) is known to counteract malperfusion. Incidence and effectiveness of IP following short- versus long-term preservation of pancreas grafts with University of Wisconsin (UW) solution has not been examined so far. PTx was performed in Lewis rats following 2-h or 18-h preservation in UW solution. Using intravital fluorescence microscopy, functional capillary density (FCD), red blood cell (RBC) velocity, IP-incidence and -frequency were analyzed. Laser Doppler flowmetry allowed for the determination of erythrocyte flux and velocity. Measurements were performed at 30, 60 and 120 min after reperfusion. Nontransplanted animals served as controls. FCD, RBC-velocity and -flux remained unchanged in the 2-h group. IP was encountered in 87% of all observation areas at 120 min. After 18-h ischemia, FCD was significantly reduced, which was paralleled by a 50% incidence of IP at 120 min. Tissue edema and leukocyte infiltration in pancreas grafts following 18-h preservation were significantly enhanced. Therefore, IP is an important mechanism aimed at improving microcirculation and UW solution is suitable to preserve vasomotion-activities enabling long-term preservation in a pancreas graft.     

A comparative study of long-term heart preservation using 12-h continuous coronary perfusion versus 1-h coronary perfusion following 11-h simple immersion

PURPOSE: We previously reported the superiority of the continuous coronary perfusion method using apparatus developed in our department. However, myocardial edema was a serious problem following this method. The purpose of this study was to attempt a comparative study of 12-h continuous perfusion and 1-h perfusion following 11-h simple immersion to evaluate the suitable method for long-term heart preservation. MATERIALS AND METHODS: HBD dogs were used in this study. After measuring baseline hemodynamics, cardiac arrest was attained and the coronary vascular beds were washed out with 4 degrees C Celsior solution. The grafts were divided into the two groups. In the CP group (n = 6), the grafts were preserved by continuous perfusion with 4 degrees C Celsior solution, and in the SI + CP (n = 6) group, the grafts were preserved with 11 h of simple immersion followed by an additional 1 h of perfusion with the same solution. The hemodynamics after orthotopic transplantation were compared. We also performed a histopathologic examination. RESULTS: Hemodynamics after reperfusion were maintained in both groups, and there were no significant differences in CO, Emax, or the rate pressure product between the two groups. In contrast, the percentage water content was significantly lower in the SI + CP group than in the CP group. Histopathologically, the myocytes were well preserved in both groups. However, ischemia-reperfusion changes were observed more frequently in the CP group than in the SI + CP group. CONCLUSION: A short-term perfusion following the simple immersion method may provide satisfactory results compared to the continuous perfusion method in long-term heart preservation.     

小鼠肝动脉重建对长时间冷保存移植肝存活率的影响

研究小鼠肝动脉重建(hepatic arterial reconstruction,HAR)对长时间冷保存移植肝存活率的影响.方法 同系雄性C57BL/6小鼠68只,分为冷保存时间(cold preservation time,CPT) 1 h组、CPT 4 h组、CPT 8 h组、CPT 16 h组、CPT 16 h+HAR组(供、受体小鼠各一半).小鼠供肝经门静脉灌注4℃ UW液后保存.肝脏移植采用缝合法(肝上下腔静脉)和袖套法 (门静脉、肝下下腔静脉) 吻合,胆管采用内支架管重建法.小鼠HAR采用含供体肝动脉的腹主动脉与受体腹主动脉端侧吻合的方法.观察术后5组受体小鼠移植肝的存活时间,用组织学检查肝细胞损伤情况,用免疫组织化学法观察肝细胞再生功能.结果 CPT 1 h、4 h、8 h组受体术后12 d移植物的存活率分别为7/7、10/10、9/9.CPT 16 h组除1例小鼠存活外,其余均在移植术后36 h内死亡,存活率为10%(1/10),CPT 16 h+HAR组受体90%(9/10)存活,两组存活率相比,差异有统计学意义(P<0.01).CPT 1 h、4 h组的移植物组织损伤程度轻,CPT 8 h 组的移植物组织损伤程度较前两组严重,但肝细胞再生活跃.CRT 16 h组的移植肝组织表现为广泛肝细胞空泡变性、坏死,肝细胞再生不明显.CPT 16 h+HAR组仅有轻度的肝窦淤血,肝细胞空泡变性、坏死改变,肝细胞再生活跃.结论 HAR可提高长时间冷保存移植肝的存活率.     

保存不同时间的大鼠部分肝脏移植后的肝细胞再生

目的 探讨保存不同时间的大鼠部分肝脏移植后的肝细胞再生及其可能机制.方法 采用近交系雄性Lewis大鼠为供、受者,按照实验设计分别将供肝于4℃UW液中保存1 h(冷缺血1 h组)、8 h(冷缺血8 h组)和16 h(冷缺血16 h组).然后进行原位肝移植.移植肝恢复血流前,用3-0丝线结扎供肝左侧中央叶、左外叶及尾状叶,保留右侧的肝叶.即可制成大鼠50%体积肝脏(以下简称"半肝")原位移植模型.术后观察各组移植肝的存活情况和肝细胞再生情况;采用逆转录聚合酶链反应测定肝组织中自细胞介素-6(IL-6)和肿瘤坏死因子α(TNF_n)的表达情况;采用Western印迹法检测肝组织中信号传导与转录因子-3(STAT-3)表达情况;采用免疫组织化学染色检测移植肝组织中细胞周期素DI(Cyelin D1)的表达和肝细胞摄取溴脱氧尿核苷(BrdU)情况.结果 各组手术成功率均为100%.与冷缺血1 h组相比,冷缺血8 h组和冷缺血16 h组移植肝组织中TNF-a(F=67.45,P<0.05)和IL-6(F=287.73,P<0.05)的表达明显增加.STAT-3的表达也明显增强.肝移植后24 h.冷缺血8 h组在胞浆和细胞核内均有Cyclin D1的表达.而冷缺血16 h组移植肝组织中未见明显的Cyclin D1表达.移植后24 h.冷缺血16 h组的BrdU染色阳性的肝细胞数无明显增多,而在冷缺血8 h组可见BrdU染色阳性的肝细胞明显增多(t=19.40,P<0.05).结论冷保存一定时限的大鼠部分肝脏在移植后可获得肝细胞再生,此过程可能通过TNF-α/IL,16/sTAT-3/Cyclin D1/DNA合成的途径进行调节;当冷保存时间达16 h后,肝细胞不能对肝脏再生早期信号起反应.     

31P-NMR study of cardiac preservation: St. Thomas' Hospital cardioplegic solution versus UW preservation solution

Ex vivo cardiac preservation was evaluated by measuring the catabolism of high-energy phosphate (ATP and creatine phosphate, CrP) using ³¹P-NMR spectroscopy. After cardioplegic arrest St. Thomas' Hospital cardioplegic solution (group A), and University of Wisconsin (UW) preservation solution (group B) were tested. The hearts were mounted in the 4.7 T horizontal bore magnet of the NMR spectrometer and were continuously perfused with the test solution under 25 cm H₂O pressure for 6 h at 10°C. Peak heights of the -phosphate of ATP and CrP were measured and expressed as percentages of the initial value. For both group A and group B, ATP declined less rapidly during preservation than CrP. In group A, ATP remained constant for 60 min while CrP decreased from the onset of preservation. After 6h of preservation 28.3% of ATP and 24.5% of CrP remained (group A). On the other hand, in group B, levels of both ATP and CrP remained much more stable: CrP did not decrease during the first 3 h of preservation, while ATP started to decrease after 5 h. At the end of preservation 76.1% of ATP and 71.5% of CrP were still present. We conclude that UW solution is superior to St. Thomas' Hospital solution for the preservation of high-energy phosphates during 6 h cardiac preservation with continuous hypothermic low-flow perfusion.     

自制SDMC-2液对离体大鼠心脏低温保存的实验研究

目的：开发一种应用简便、保存效果好的新心脏保存液。方法：实验动物采用SD雄性大鼠。分为对照组（A组），Stanford液保存组（B组），SDMC－1液保存组（C组），SDMC－2液保存组（D组）。实验组中，每组心脏均经某一种液体停搏、灌洗并保存8h，然后通过Langendorff灌流装置再灌注，分别测定保存未及再灌注后心肌的ATP、肌酸激酶（CK）、含水量及组织学检查，以及左心室功能的恢复、冠脉流量（CF）。结果：B、C、D三组各项检测指标与A组比较均有不同和程度降低（P＜0．05或0．01）。左心室功能指标；D组优于B、C组；CF：D组高于B、C组；ATP、CK含量：保存末及再灌注后D组优于B、C组，再灌注前后比较，B、C组降低；B组水含量高且再灌注后加重；电镜：D组细胞结构损伤轻，B组损伤最重。结论：SDMC－2液配方更为合理，长时间低温保存离体心脏，效果优良。可直接用于心脏停搏、原位灌洗、保存及移植过程中的灌注，简化了心脏保存过程。     

Combining Cariporide with Glyceryl Trinitrate Optimizes Cardiac Preservation During Porcine Heart Transplantation

Sodium–hydrogen exchange inhibitors, such as cariporide, are potent cardioprotective agents, however, safety concerns have been raised about intravenously (i.v.) administered cariporide in humans. The aim of this study was to develop a preservation strategy that maintained cariporide's cardioprotective efficacy during heart transplantation while minimizing recipient exposure. We utilized a porcine model of orthotopic heart transplantation that incorporated donor brain death and 14 h static heart storage. Five groups were studied: control (CON), hearts stored in Celsior; CAR1, hearts stored in Celsior with donors and recipients receiving cariporide (2 mg/kg i.v.) prior to explantation and reperfusion, respectively; CAR2, hearts stored in Celsior supplemented with cariporide (10 μmol/L); GTN, hearts stored in Celsior supplemented with glyceryl trinitrate (GTN) (100 mg/L); and COMB, hearts stored in Celsior supplemented with cariporide (10 μmol/L) plus GTN (100 mg/L). A total of 5/5 CAR1 and 5/6 COMB recipients were weaned from cardiopulmonary bypass compared with 1/5 CON, 1/5 CAR2 and 0/5 GTN animals (p = 0.001). Hearts from the CAR1 and COMB groups demonstrated similar cardiac function and troponin release after transplantation. Supplementation of Celsior with cariporide plus GTN provided superior donor heart preservation to supplementation with either agent alone and equivalent preservation to that observed with systemic administration of cariporide to the donor and recipient.     

Continuous perfusion of donor hearts with oxygenated blood cardioplegia improves graft function

Donor hearts cannot be preserved beyond 6 h using cold storage (CS). Improving preservation methods may permit prolonged storage of donor heart. We compared graft function in large animal model after prolonged preservation (8 h) using continuous perfusion (CP) and CS method. Twenty‐four miniature pigs were used as donors and recipients. Donor hearts were either stored in University of Wisconsin solution (UW solution) for 8 h at 0–4 °C (CS group, n = 6) or were continuously perfused with oxygenated blood cardioplegia at 26 °C for 8 h (CP group, n = 6). After preservation, hearts were transplanted into recipients and reperfused for 3 h. Left ventricular (LV) function, cardiac output (CO), malondialdehyde (MDA) and adenosine triphosphate (ATP) levels, and water content were measured. Although water content of CP hearts was higher than that of CS, LV contractility and diastolic function of CP hearts were superior to those of CS. In addition, CP hearts performed better than CS hearts on CO in working heart state. ATP was better preserved and MDA levels were lower in CP hearts compared with those of CS (P < 0.0001). Donor hearts can be preserved longer using continuous perfusion with oxygenated blood cardioplegia and this method prevents time‐dependent ischemic injury.     

膀胱尿路上皮癌患者血清环氧合酶-2的检测

目的 探讨血清环氧化酶-2(COX-2)定量测定在膀胱尿路上皮细胞癌(BUC)诊断及随访中的应用价值.方法 采用酶联免疫测定(EIA)法定量测定95例经病理确诊为BUC患者血清中COX-2含量,WHO分级G_1 48例,G_2 39例,G_3 8例.TNM分期Tis及Ta 9例,T_1 33例,T_2 25例,T_3 20例,T_4 8例.40例BUC术后经膀胱镜复查阴性患者、20例癌前病变患者(膀胱黏膜白斑14例,腺性膀胱炎6例)、35例其他泌尿系疾病患者及60例健康对照者进行检测.结果 BUC组血清中COX-2含量为(1.91±0.65)mg/L,显著高于其他组;COX-2在表浅(Tis+Ta+T_1)与侵袭BUC(T_2+L_3+T_4)含量(1.40±0.71)mg/L与(2.38±1.18)ms/L,G_1G_2与G_3含量分别为(1.29±0.51)mg/L、(2.13±0.69)ms/L与(2.33±0.81)mg/L,COX-2含量随BUC分期、分级增高而增加,初发(1.80 ±0.81)mg/L与复发(1.81±1.02)ms/L肿瘤间COX-2含量差异无统计学意义(P＞0.05).结论 BUC患者血清中COX-2水平测定有可能成为一项BUC诊断和术后监测的指标.     

31P-NMR study of cardiac preservation: St. Thomas' Hospital cardioplegic solution versus UW preservation solution

Abstract. Ex vivo cardiac preservation was evaluated by measuring the catabolism of high-energy phosphate (ATP and creatine phosphate, CrP) using ³¹P-NMR spectroscopy. After cardioplegic arrest St. Thomas' Hospital cardioplegic solution (group A), and University of Wisconsin (UW) preservation solution (group B) were tested. The hearts were mounted in the 4.7 T horizontal bore magnet of the NMR spectrometer and were continuously perfused with the test solution under 25 cm H₂O pressure for 6 h at 10°C. Peak heights of the β-phosphate of ATP and CrP were measured and expressed as percentages of the initial value. For both group A and group B, ATP declined less rapidly during preservation than CrP. In group A, ATP remained constant for 60 min while CrP decreased from the onset of preservation. After 6 h of preservation 28.3% of ATP and 24.5% of CrP remained (group A). On the other hand, in group B, levels of both ATP and CrP remained much more stable: CrP did not decrease during the first 3 h of preservation, while ATP started to decrease after 5 h. At the end of preservation 76.1% of ATP and 71.5% of CrP were still present. We conclude that UW solution is superior to St. Thomas' Hospital solution for the preservation of high-energy phosphates during 6 h cardiac preservation with continuous hypothermic low-flow perfusion.     

Small bowel preservation for intestinal transplantation: a review

Intestinal transplantation has become the therapy of choice for patients with intestinal failure and life‐threatening complications from total parenteral nutrition. Results, however, remain inferior as compared with other transplant types with the quality of the organ graft as the most important factor of outcome after transplantation. The intestine is extremely sensitive to ischemia. Unfortunately, a relatively long ischemic preservation period is inevitable. The current standard in organ preservation [cold storage (CS) with University of Wisconsin solution] was developed for kidney/liver preservation and is suboptimal for the intestinal graft despite good results for other organs. This review aimed at appraising the results from the use of previously applied and recently developed preservation solutions and techniques to identify key areas for improvement. As the studies available do not reveal the most effective method for intestinal preservation, an optimal strategy will result from a synergistic effect of different vital elements identified from a review of published material from the literature. A key factor is the composition of the solution using a low‐viscosity solution to facilitate washout of blood, including amino acids to improve viability, impermeants and colloids to prevent edema, and buffer for pH‐homeostasis. Optimizing conditions include a vascular flush before CS and luminal preservation. The most effective composition of the luminal solution and a practical, clinically applicable optimal technique are yet to reach finality. Short‐duration oxygenated arterial and/or luminal perfusion have to be considered. Thus, a tailor‐made approach to luminal preservation solution and technique need further investigation in transplant models and the human setting to develop the ultimate technique meeting the physiologic demands of the intestinal graft during preservation.     

Perfluorohexyloctane improves long-term storage of rat pancreata for subsequent islet isolation

Pancreas oxygenation by means of the hyperoxygen carrier perfluorodecalin (PFD) has been established to prevent ischemically induced damage from cold-stored pancreata. However, large-scale studies did not confirm the promising results that had been observed in smaller donor populations. This study assessed whether islet isolation from pancreata stored for prolonged periods can be improved by utilizing the new oxygen carrier perfluorohexyloctane (F6H8) characterized by lower gravity and higher lipophilicity than PFD. Subsequent to 24 h of storage in either oxygenated PFD or F6H8, the rat pancreata were assessed for the intrapancreatic partial oxygen pressure (pO₂) and subsequently processed with current standard procedures. The intrapancreatic pO₂ was nearly identical in rat pancreata stored either in PFD or F6H8. Nevertheless, rat islet isolation outcome was significantly increased in terms of yield, integrity, in vitro function and post-transplant outcome after transplantation in diabetic nude mice when F6H8 was used as oxygen carrier. This proof-of-concept study demonstrated in rats that islet isolation performed after long-term storage of oxygenated pancreatic tissue can be significantly improved if PFD was replaced by F6H8.     

临床肾脏保存2086例经验

目的：总结高渗枸橼酸盐腺嘌呤（HC－A）肾保存液2086例临床应用经验。方法：1980年8月至2000年12月连续2086例肾移植，供肾采用HC－A肾保存液保存。按冷缺血时间分组观察移植后血肌酐，移植肾存活率和平均存活时间。结果：冷缺血时间＜12h(573例）、12－24h（779例）和＞24h(734例）组移植肾平均存活时间分别为9．32、10．93和7．23年，后者与前两组比较差异均有显著性意义（P＜0．05）；移植后血肌酐、移植肾存活率在各组间差异无显著性意义（P＞0．05）。约3．16％的移植肾因保存问题出现肾功能异常。结论：应用HC－A肾保存液可取得较好的近期肾功能恢复和长期移植肾存活，冷缺血时间以24h内最佳。