白细胞介素-2单克隆抗体对急性排斥反应中细胞因子表达的影响

目的　观察白细胞介素 2单克隆抗体 (IL 2Mab)对同种大鼠心脏移植物存活时间及局部细胞因子网络的影响。方法　分A组 (对照组 ) ,B组 (IL 2Mab组 )。每组 12只。分别静脉给予生理盐水及抗白细胞介素 2单克隆抗体 (A3 8 3 ) ,采用改良的移植术式建立移植模型。常规监测排斥反应发生情况。每组 5只用于观察移植物存活时间 ,7只用于动态切取标本。应用逆转录 聚合酶链反应 (RT PCR)的方法检测移植物局部细胞因子如IL 1β、IL 2、CD2 5、IL 4、IL 5、IL 6、IL 10、肿瘤坏死因子 (TNF) α、干扰素 (IFN ) γ的表达水平。结果　IL 2Mab组移植心存活时间( 2 6.4± 5 .7)d显著长于对照组 ( 8.3± 1.7)d ,实验组IL 1β、IL 5、IL 6、IL 10、IFN γ的表达较强于对照组 ,而IL 2、CD2 5、IL 4、TNF α的表达反之。结论　IL 2Mab能够显著的延长移植物生存时间 ,但对细胞因子表达模式的偏离产生的预期效果并不理想 ,其可能的机制在于细胞因子网络的复杂性。     

眼镜蛇毒因子消耗补体对大鼠移植心急性排斥反应的抑制作用

目的研究中华眼镜蛇毒因子(CVF)消耗补体对大鼠心脏移植急性排斥反应的影响。方法以近交系BN大鼠为供者,Lewis大鼠为受者,建立腹腔异位心脏移植模型。实验分为2组,每组8只。CVF组:心脏移植术前3 d、2 d时,经受者尾静脉注射CVF 50μg／kg;术前12 h至移植心停跳时,经尾静脉注射CVF 20μg／kg,每2 d注射1次。对照组:术前、术后不给予受者任何特殊处理。术后观察移植心的存活时间,测定术后第1、3、5和6d及移植心停跳时的血清总补体活性(CH50法)、移植心C3沉积及CD3+T细胞浸润情况,并观察移植心的病理变化。结果CVF组和对照组的移植心存活时间分别为(11．69±0．72)d和(6．65±0．35)d,两组比较,差异有统计学意义(P<0．01)。CVF组移植心组织内C3沉积和CD3+T细胞浸润程度均较对照组同期明显减轻,病理损害程度也较对照组同期明显减轻。结论CVF消耗补体对大鼠心脏移植急性排斥反应起到了明显的抑制作用,从而延长移植心存活时间。     

急性排斥反应时Fractalkine及其受体在移植心脏中的表达

目的　探讨急性排斥反应过程中Fractalkine(FKN)及其受体CX3CR1在移植心脏局部表达的意义及环孢素A(CsA)对它们的影响。　方法　施行大鼠异位心脏移植术 ,移植大鼠分为 3组 ,每组 45只 ,对照组 5只。SD大鼠间的移植为同系移植组 (A组 ) ,Wistar至SD大鼠的移植分为未用CsA干预组 (B组 )及CsA干预组 (C组 ) ,健康SD大鼠为对照组。采用RT PCR方法检测排斥反应中移植心脏局部FKNmRNA的表达水平 ,免疫组化方法检测FKN和CX3CR1的蛋白表达水平。　结果FKNmRNA与蛋白在A组各时间点和对照组均呈低水平表达 ;在B组的表达变化与急性排斥反应的进程相关 ,术后第 7天FKNmRNA表达上调至峰值 (0 8± 0 2 6) ;C组应用CsA后 ,FKNmRNA表达峰值显著低于B组 (t=2 3 90 ,P <0 0 5 )。FKN和CX3CR1蛋白分别定位于移植心脏血管内皮细胞及间质浸润的单个核细胞中。　结论　急性排斥反应过程中 ,FKN及其受体CX3CR1表达上调 ,与移植物间质单个核细胞浸润密切相关 ;抑制FKN CX3CR1通路的活化可能是CsA发挥作用的又一分子免疫学机制     

ClC-3在大鼠异位心脏移植急性排斥期的表达及意义

目的观察电压门控氯通道-3(C lC-3)在大鼠异位心脏移植急性排斥期中的表达及意义。方法以SD大鼠为供者,W istar大鼠为受者,建立大鼠腹部心脏异位移植模型,分为两组,每组32对。对照组:用生理盐水灌胃;环孢菌素A(C sA)组:用C sA灌胃干预。每组8只观察移植心存活时间,术后1、3、5和7d各切取6只标本,常规组织切片监测排斥反应,以原位末端标记(TUNEL)法检测心肌细胞凋亡,逆转录-聚合酶链反应(RT-PCR)检测移植心肌组织C lC-3的表达。结果C sA组移植心存活时间明显长于对照组(15.4±5.1d vs.7.6±1.5d,P<0.05);C sA组各采样时段的免疫排斥反应分级及心肌凋亡指数明显低于对照组(P<0.05),而C lC-3表达强度均强于对照组(P<0.05)。C sA干预能明显降低免疫排斥反应分级及心肌凋亡指数,改善C lC-3表达强度的降低。结论移植心脏中C lC-3表达水平的高低与心脏急性免疫排斥反应的轻重及心肌细胞凋亡指数的高低密切相关,提示C lC-3在移植心脏免疫排斥反应心肌细胞凋亡坏死中有着重要的作用。     

细胞因子在心脏移植急性排斥反应中的表达及其作用机理

目的观察同种大鼠心脏移植急性排斥反应中,局部细胞因子网络的变化及其机理.方法健康雄性Wistar大鼠(受体)和SD大鼠各48只,将接受移植心脏的Wistar大鼠分4组,每组12只.A组对照组;B组抗白介素2单克隆抗体(IL-2Mab)组;C组环孢菌素A(CsA)组;D组IL-2Mab加CsA组.4组大鼠分别静脉给予生理盐水、抗白介素2单克隆抗体及口服CsA、静脉给予抗白介素2单克隆抗体加口服CsA,采用改良的移植术式建立移植模型.常规监测排斥反应发生情况.应用RT-PCR的方法于术后第1、3、5、7、9、11、14天动态检测移植物局部细胞因子IL-1β、IL-2、CD25、IL-4、IL-5、IL-6、IL-10、TNFα、IFNγ的表达水平.结果移植心脏存活时间,A组为(8.3±1.7)d;B组为(29.2±7.1)d;C组为(26.4±5.7)d;D组为(55.0±11.6)d.B、C、D组移植心脏存活时间显著延长,与A组相比,差异有极显著性意义(P＜0.01).存活时间较长的移植心脏的淋巴细胞浸润和心肌坏死的程度比存活时间较短的心脏明显减轻.IL-1β的表达在各组均较高;IL-4、IL-5、IL-6、IL-10的表达水平在移植心脏存活时间较长的组较高;而IL-2、CD25、IFN-γ、TNFα的表达则相对较低;4组相比差异有显著性意义(P＜0.05).结论细胞因子网络在心脏移植排斥反应中发生了相应的变化,并与干预的因素及移植物存活时间有密切的关系.IL-2Mab、CsA联合用药促使TH1类细胞因子向TH2类细胞因子整体偏离,这种免疫偏离使移植心脏存活时间显著延长.     

白介素10在心脏移植排斥反应中的表达及机制

目的　研究白介素10(IL-10)在大白鼠心脏移植排斥反应中心脏局部的表达变化情况，并探讨其参与排斥反应的可能机制。方法　实验动物分5组，A组(对照组)、B组(供体特异性全血输注组)、C组(Anti-IL-2Mab组)、D组(Anti-IL-4Mab组)、E组(Anti-IL-2Mab+环孢霉素A组)，处理受体。将大鼠移植心移植到受体的颈部，观察移植心存活时间、动态病理变化。并于移植术后第1、3、5、7、9、11、14d分别取移植心置于液氮中待测。应用半定量的RT-PCR法动态检测移植心IL-10的表达情况。结果　各组移植心存活时间分别为(8.3±1.7)d、(29.2±7.1)d、(26.4±5.7)d、(10.2±1.9)d、(55.0±10.6)d。其中B组、C组与A组比较差异有显著意义，E组与A组及C组比较分别有极显著意义和显著意义。IL-10在B组、C组及E组均有较强的表达，在A组及D组表达微弱，并与移植物的存活时间密切相关。结论　IL-10参与调节移植排斥反应，其机制可能为Th类细胞因子的免疫偏离。应用Th1类细胞因子单克隆抗体并联用免疫抑制剂可以有效的抑制移植排斥反应，从而延长移植物的存活期。     

大鼠原位肝移植术后急性排斥反应中 Fractalkine的表达及意义

目的利用直视下套入式吻合肝动脉加袖套法吻合门静脉建立的大鼠全血供肝移植模型,研究同种异体大鼠肝移植术后早期急性排斥反应中Fractalkine（Fkn）的表达情况。方法制备SD-Wistar大鼠全血供肝移植模型,随机分为两组,每组20只。对照组：于移植术后第1天开始腹腔内注射生理盐水（3ml/kg）;实验组：于移植术后第1天开始腹腔内注射环孢素A（3mg/kg）。术后观察大鼠一般情况,并于第3、5及7天分别处死5只大鼠,取肝脏标本,观察移植肝组织排斥反应强度（rejection activity index,RAI）及Fkn表达情况;余大鼠观察生存时间。结果对照组存活18只,实验组存活19只。实验组较对照组术后一般情况好,存活时间为19.50±4.51d,与对照组7.60±1.60d比较,差异有统计学意义（P〈0.05）。组织学观察：对照组移植肝小叶结构清楚,汇管区增大,大量淋巴细胞浸润;实验组移植肝组织RAI明显降低。术后第3、5及7天,对照组RAI为3.80±0.35、5.90±0.87及7.50±1.30,实验组为3.10±0.21、3.90±0.41及4.50±0.52。两组术后第7天RAI比较差异有统计学意义（P〈0.01）。免疫组织化学观察：两组移植肝组织中均见细胞浆或细胞膜有棕色颗粒的Fkn表达,但实验组表达较弱。术后第3、5及7天,对照组Fkn细胞数为8.20±0.57、21.30±3.30及25.70±4.91,实验组分别为8.30±0.56、10.30±0.67及11.70±1.23;两组第5、7天比较差异有统计学意义（P〈0.01）。结论Fkn参与了同种异体大鼠肝移植急性排斥反应,可作为诊断大鼠肝移植急性排斥反应发生的指标之一。环孢素A可以通过抑制Fkn表达来抑制排斥反应发生的强度。     

环孢菌素A抑制大鼠同种心脏移植急性排斥反应中趋化因子受体CCR5表达的研究

目的观察大鼠同种心脏移植急性排斥反应中趋化因子受体CCID的表达及环孢菌素A（CsA）的抑制作用。方法分两组建立同种大鼠颈部心脏移植模型：对照组（n=25）和新山地明组（CsA组，n=25），各5例观察移植心脏存活时间。于移植术后第1、5、7、14天分别取移植心组织各5例，逆转录-聚合酶链反应（RT—PCR）检测移植心组织内趋化因子受体CCR5mRNA不同时间点的表达水平，免疫组织化学方法检测移植心组织内趋化因子受体CCR5分子的表达差异。结果对照组移植心存活时间为（11．6±1．5）d，CsA组移植心存活时间为（22．4±5．1）d，两组问移植心存活时间差异有统计学意义（P〈0．01）。急性排斥组和CsA处理组大鼠移植心脏在术后第5、7、14天都可检测到趋化因子受体CCR5mRNA阳性表达，但CsA处理组趋化因子受体CCRSmRNA的表达明显弱于急性排斥组。同样急性排斥组和CsA处理组大鼠移植心脏在术后第5、7、14天都可检测到趋化因子受体CCR5分子的表达，CsA处理组趋化因子受体CCR5分子的表达相对较弱。结论趋化因子受体CCR5在早期移植免疫事件中具有重要的作用，CsA能部分抑制趋化因子受体CCR5的表达，并与移植物存活时间延长有一定的关系。     

Th1/Th2细胞因子mRNA的表达与心脏移植免疫耐受的关系

目的探讨Th1/Th2细胞因子信使核糖核酸(mRNA)表达改变与心脏移植免疫耐受的关系. 方法采用大鼠腹部心脏移植模型,将30只大鼠随机分成对照组、排斥反应组、免疫耐受组,每组10只.观察移植心脏存活时间,供心病理学改变,受者脾和心脏中Th1/Th2细胞因子白细胞介素2(IL-2)、γ干扰素(IFN-γ)、白细胞介素4(IL-4)、白细胞介素10(IL-10) mRNA表达水平. 结果免疫耐受组供心存活时间为85.28±7.48天,较排斥反应组的7.33±1.03天显著延长(P＜0.01);排斥反应组供心见大量炎性细胞浸润,免疫耐受组供心仅见少量炎性细胞浸润;排斥反应组Th1细胞因子IL-2、IFN-γ mRNA表达较对照组增强,免疫耐受组减弱;排斥反应组Th2细胞因子IL-4、IL-10 mRNA表达较对照组减弱,免疫耐受组增强. 结论 Th1/Th2细胞因子的动态平衡在移植耐受中起重要作用,Th1向Th2偏离是移植耐受的机制之一.     

CD25单克隆抗体影响心脏移植排斥反应及细胞因子表达的实验研究

目的研究抗白细胞介素-2受体(CD25)单克隆抗体参与大鼠心脏移植排斥反应及调节细胞因子(CK)表达的作用及其机制.方法建立大鼠颈部心脏移植动物试验模型,实验动物随机分为4组,分别单独或联合应用环孢霉素A(CysA)及CD25单克隆抗体(舒莱)来干预心脏移植排斥反应,观察其供心存活时间,并应用RT-PCR的方法检测移植物局部CK如白细胞介素(IL)-1β、IL-2、CD25、IL-4、IL-5、IL-6、IL-10、肿瘤坏死因子(TNF)-α、干扰素(IFN)-γ在移植术后1、3、5、7、9、11和14d 动态表达水平的动态变化.结果 B、C、D组移植心存活时间显著延长,分别为(26.4±5.7)、(29.2±7.1)、(55.0±11.6)d,尤以CysA+舒莱组最显著(P<0.05).CD25的表达在各组中的变化较为明显,在用药组明显降低(P<0.05);IL-4、IL-5、IL-6、IL-10的表达在移植心延长组较强,而IL-2、CD25、IFN-γ、TNF-α的表达则相对较弱.各组细胞因子(CK)表达的高峰时期均与移植物的存活时间及病理变化有一定的关系.结论CK表达在移植排斥反应中发生了相应的变化,并与干预的因素及移植物存活时间有密切的关系,其作用机制多样.二联用药对整个CK网络的作用方式是TH1类CK向TH1类CK整体偏离,而这是这种免疫偏离的机制使本组移植心存活时间延长最显著.     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Immunomodulation in Transplantation with Photopheresis

Abstract: Photopheresis is a technique in which peripheral blood mononuclear cells, in the presence of a photoacti-vatable compound, are exposed extracorporeally to ultraviolet A light and reinfused, inducing a host autoregula-tory immune response. Experimental work and ongoing clinical studies are helping to define the role of this novel, safe, and non-toxic immunomodulating technology in the field of transplantation.