不同数目骨髓间充质干细胞移植对大鼠肺动脉高压的作用及内皮素-1表达的影响

目的探讨不同数目骨髓间充质干细胞(mesenchymal stem cells,MSCs)移植对野百合碱(MCT)诱导大鼠肺动脉高压的治疗作用,以及对内皮素-1(endothelin-1,ET-1)表达的影响。方法成年雄性Wistar大鼠40只(体重180～250 g),按随机数字表法分为4组,每组10只。A组:大鼠腹腔注射MCT 60 mg/kg,经颈外静脉注入1×106MSCs;B组:大鼠腹腔注射MCT 60 mg/kg,经颈外静脉注入5×105MSCs;MCT组:大鼠腹腔注射MCT60 mg/kg和等量磷酸盐缓冲液(PBS);对照组:大鼠腹腔注入等量生理盐水和等量PBS。MSCs移植4周后测定右心室收缩压(RVSP),计算心室比,即右心室/(左心室+室间隔)[RV/(LV+VS)];观察肺组织形态学改变;检测肺组织ET-1基因表达和血清ET-1的含量。结果 MSCs移植4周后,A组RVSP和RV/(LV+VS)与MCT组比较明显降低[(35.8±4.2)mm Hg vs.(47.2±10.1)mm Hg,P<0.01;(0.357±0.032)vs.(0.452±0.056),P<0.01];而B组与MCT组比较差异无统计学意义(P>0.05)。A组肺小动脉中膜厚度较MCT组明显变薄[(19.7%±3.0%)vs.(26.8%±3.6%),P<0.01];而B组则差异无统计学意义。逆转录酶-聚合酶链反应(RTase-PCR)检测结果显示,MCT组肺组织ET-1 mRNA表达最强,A组肺组织ET-1 mRNA与MCT组比较明显减弱,B组表达与MCT组接近。A组血清ET-1含量与MCT组比较明显减少。结论 MSCs静脉移植对MCT诱导的肺动脉高压具有抑制作用,并能减少肺组织ET-1的mRNA表达及血清ET-1浓度。采用1×106MSCs移植具有较好的治疗作用。     

骨髓间充质干细胞对急性胰腺炎大鼠p38丝裂原活化蛋白激酶信号通路表达的影响

目的 观察骨髓间充质干细胞(MSCs)对急性胰腺炎(AP)大鼠p38丝裂原活化蛋白激酶(p38MAPK)信号通路的影响,探讨其减轻胰腺炎的作用机制.方法 采用腹腔注射L-精氨酸建立大鼠AP模型.SD大鼠随机分4组:AP未治疗组(24只);MSCs移植组(24只);p38MAPK抑制组(24只)和正常对照组(6只).流式细胞术检测MSCs表面标记物;逆转录-聚合酶链反应(RT-PCR)方法检测胰腺组织p38MAPK mRNA表达变化;同时观察组织形态学改变.结果 (1)未治疗组大鼠在建模后1h时胰腺组织p38MAPK mRNA表达显著升高并达到顶峰(P＜0.01);移植MSCs后表达明显降低,与正常对照组比较,差异无统计学意义(P＞0.05).(2)未治疗组血清炎性因子水平分别为:肿瘤坏死因子(TNF)-α(614.8 ±54.6)ng/L、白细胞介素(IL)-1(3040.5±506.4)ng/L、IL-17(4.5±0.4)U/L,胰腺组织中性粒细胞趋化因子(CINC)和单核粒细胞趋化因子(MCP-1)染色阳性率均明显升高(P＜0.05);移植MSCs后,CINC、MCP-1染色阳性率显著下降,血清炎性因子水平分别为:TNF-α( 277.5±60.8)ng/L、IL-1( 1056.2±563.1)ng/L、IL-17(1.2±0.4)U/L,两组比较差异有统计学意义(P＜0.05).(3)胰腺组织苏木素-伊红(HE)染色显示,未治疗组有大量炎性细胞浸润,胰腺细胞破坏明显,腺体结构紊乱,而移植组仅见少量炎性细胞浸润,细胞偶有破坏,排列整齐,结构有序.结论 急性胰腺炎时,胰腺组织内p38MAPK mRNA表达上调,胰腺组织损伤严重.MSCs移植可以明显抑制p38MAPK mRNA表达,降低胰腺组织内趋化因子和血清炎性因子水平,从而减轻胰腺损伤.     

大鼠野百合碱肺高压模型基质金属蛋白酶-1、基质金属蛋白酶-9 mRNA的表达

目的 观察基质金属蛋白酶(MMP)-1、-9在大鼠野百合碱肺高压模型中的表达.方法 SD大鼠24只,随机分为野百合碱注射组(MCT)和对照组(Con).MCT组给予野百合碱60 mg/kg单次右侧皮下注射.饲养6周后,采集肺组织样本进行肺小动脉形态学测量,原位杂交和逆转录-聚合酶链反应(RT-PCR)检测.结果 MCT组肺小动脉横断面的厚度指数(TI)及面积指数(AI)的均值都高于Con组(TI:0.41±0.13比0.13 ±0.07,P＜0.05;AI:0.64±0.15比0.23 ±0.11,P＜0.05).MMP-1、-9主要分布于肺小动脉内皮细胞和外膜成纤维细胞,MCT组肺组织中MMP-1、-9mRNA转录水平高于对照组(0.72±0.13比0.28±0.01,P＜0.05;0.85±0.15比0.39±0.12,P＜0.05).结论 MMP-1、-9活性表达的增强,参与了肺高压肺血管重构的机制.     

两种大鼠肺动脉高压模型肺血管重塑的血流动力学、组织学和体视学指标变化

目的 构建大鼠颈动静脉分流型(CA-JV)和野百合碱诱导型(MCT)肺动脉高压模型,观察两种肺动脉高压模型肺血管重塑的血流动力学、组织学和体视学指标改变.方法 36只Spargue-Dawley大鼠,对照组、CA-JV和MCT肺动脉高压模型各12只,MCT组6周,其余两组12周后测定右心室收缩压(RVSP),并取左下肺组织测定肺小动脉横截面厚度指数(TI)和面积指数(AI)以及肺小动脉纤维比例.结果 大鼠分流型与药物型肺动脉高压模型中RVSP(37.69±3.00、43.99±4.60)、TI(0.43±0.16、0.41±0.13)和AI(0.65±0.19、0.64±0.15)和肺小动脉纤维比例(33.59±7.58、30.33±7.24)均较对照组均显著升高,药物型模型RVSP升高更明显(P<0.05),分流型模型肺小动脉纤维比例更高(P<0.05).结论 两种肺动脉高压模型均可以造成大鼠血流动力学变化和肺血管结构改变,不同模型肺血管重塑存在不同特点.     

pEGFP-C1/Akt体外转染骨髓间充质干细胞对后肢缺血大鼠血管生成的影响

目的 探讨经肌肉注射转染pEGFP-C1/Akt的鼠骨髓间充质干细胞(MSCs)对后肢缺血大鼠血管生成的影响.方法 Wistar大鼠30只,制成双后肢缺血模型,双盲法随机分为基因治疗组(肌注经pEGFP-C1/Akt转染的MSCs)、非基因治疗组(肌注MSCs)及对照组(肌注PBS液).造模前、造膜后即刻及MSCs移植后1～7 d内,每天用红外线皮温仪测定大鼠后肢皮温变化.28 d时经动脉造影观察后肢血管生成情况; 免疫组化染色检测后肢毛细血管密度; 逆转录-多聚酶链反应(RT-PCR)和Western blot法检测后肢肌肉组织中Akt及血管内皮细胞生长因子(VEGF)的 mRNA和蛋白的表达.结果 移植3 d后基因治疗组大鼠后肢皮温升高明显.28 d时经动脉造影观察基因治疗组后肢侧支血管生成明显; 荧光显微镜观察有绿色荧光细胞在基因治疗组的内收肌和半膜肌分布.毛细血管密度: 基因治疗组为(7.1±0.3)个/高倍镜,非基因治疗组为(4.2±0.4)个/高倍镜,对照组为(1.3±0.2)个/高倍镜,各组间差异均有统计学意义(P＜0.01).Akt及VEGF的 mRNA和蛋白的表达分析: 基因治疗组Akt mRNA(2.44±0.14)和蛋白(1.12±0.13)及VEGF mRNA(1.11±0.11)和蛋白(0.97±0.13)表达水平均明显高于非基因治疗组Akt mRNA(1.58±0.13)和蛋白(0.78±0.12)及VEGF mRNA(0.78±0.14)和蛋白(0.67±0.11)以及对照组Akt mRNA(0.64±0.11)和蛋白(0.36±0.12)及VEGF mRNA(0.56±0.11)和蛋白(0.33±0.13)的表达水平(P＜0.01),后2组间比较差异亦均有统计学意义(P＜0.01).结论 pEGFP-C1/Akt体外转染骨髓MSCs促进后肢缺血大鼠血管生成的效果优于单纯MSCs治疗,为基因转染MSCs治疗缺血性疾病提供可能.     

蛛网膜下腔移植骨髓间充质干细胞对大鼠慢性神经病理性痛的影响

目的 探讨蛛网膜下腔移植骨髓间充质干细胞(MSCs)对大鼠慢性神经病理性痛的影响.方法 雌性SD大鼠140只,体重180～200 g,采用坐骨神经分支选择损伤(SNI)法制备慢性神-经病理性痛模型,术后2周,随机分为4组(n=35):模型组(NP组)、MSCs组、PBS组和骨髓未贴壁单核细胞组(BNMCs组).MSCs组、PBS组、BNMCs组蛛网膜下腔分别注射1×105/μl的第3代MSCs悬液10μl、PBS 10μl、1×105/μl的BNMCs悬液10μl.于术前、术后2周、移植后1、2、3、4、5周(T0-6)时测定机械痛阈.同时于T1～6时测定痛阈后随机选择5只大鼠取脊髓腰膨大组织,使用RT-PCR法测定脑源性神经营养因子(BDNF)mRNA表达.结果 与T0时比较,T1时各组机械痛阈降低,T2～6时NP组、PBS组、BNMCs组机械痛阈降低(P＜0.05).与T1时比较,MSCs组T2～6时机械痛阈升高,T2-4时BDNF mRNA表达上调(P＜0.05),PBS组和BNMCs组其余时点各指标差异无统计学意义(P＞0.05).与NP组比较,MSCs组机械痛阈升高,BDNFmRNA表达上调(P＜0.05),PBS组和BNMCs组各指标差异无统计学意义(P＞0.05).结论 蛛网膜下腔移植MSCs可减轻大鼠慢性神经病理性痛,其机制可能与上调脊髓BDNF mRNA表达有关.     

大鼠野百合碱肺高压模型血小板衍生生长因子mRNA的表达及作用

目的 观察血小板衍生生长因子(PDGF)A、B及其α,β受体在大鼠野百合碱肺高压模型中的表达,探讨PDGF在肺血管重构中的作用.方法 SD大鼠24只,体质量250～300g,随机分为野百合碱注射组(MCT,12只)和对照组(Con,12只).MCT组给与野百合碱60 mg/kg单次皮下注射.喂养6周后,使用逆转录-聚合酶链反应(RT-PCR)观察肺组织PDGF-A、PDGF-B及其α、β受体mRNA转录量的变化.结果 MCT组肺组织中PDGF-A、PDGF-B、PDGFR-α、PDGFR-β的mRNA转录水平都高于对照组(1.5609±0.1246比0.4057±0.0007,P＜0.05;0.4810±0.0733比0.2639±0.0070,P＜0.05:0.4963±0.0137比0.3038±0.0859,P＜0.05;1.1257±0.2490比0.0736±0.0185,P＜0.05).结论 血小板衍生生长因子(PDGF)-A、PDGF-B及其α、β受体活性表达的增强,参与了肺动脉高压肺血管重构的机制.     

骨髓间质干细胞经静脉移植对大鼠脊髓损伤后TNF-α、IL-1β mRNA表达的影响

目的研究大鼠骨髓间质干细胞(MSCs)经静脉移植对脊髓损伤(SCI)后肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)表达的影响。方法运用改良Allen法制备大鼠脊髓外伤性截瘫模型,假手术组6只,损伤组84只随机分为对照组和rMSCs移植组。对照组和rMSCs移植组、假手术组于损伤后10min经尾静脉分别注射PBS1ml和rMSCs单细胞PBS悬液1ml。移植后3h、6h、12h、24h、3d、7d、14d,应用RT-PCR方法检测损伤大鼠脊髓TNF-α、IL-1βmRNA表达变化情况。结果对照组和rMSCs移植组损伤脊髓TNF-α、IL-1βmRNA表达较假手术组有明显增加(P0.05);rMSCs移植组与对照组比较,TNF-α、IL-1βmRNA表达受到明显抑制(P0.05)。结论 rMSCs静脉移植后能改变脊髓损伤区的微环境,使损伤脊髓局部的TNF-α、IL-1β表达程度降低。这可能是减少脊髓继发性损伤,促进损伤大鼠运动功能恢复的机制之一。     

人羊膜间充质干细胞移植对大鼠脊髓损伤后NGF、BDNF和Nogo-A mRNA表达的影响

目的:观察人羊膜间充质干细胞(hAMSCs)移植对大鼠脊髓损伤后神经生长因子(NGF)、脑源性神经营养因子(BDNF)及轴突生长抑制因子(Nogo-A)mRNA表达的影响.方法:成年雌性SD大鼠24只,随机分成hAMSCs移植组(12只)、磷酸盐缓冲液(PBS)对照组(12只).体外分离培养、鉴定hAMSCs,并以终浓度为10μg/ml 4,6-二脒基-2-苯基吲哚(DAPI)荧光染料标记hAMSCs.在建立大鼠T1 1脊髓全横断损伤模型后,立即以微量注射器吸取约3×106个hAMSCs悬液于横断损伤处头尾两端原位移植,对照组注射相同体积的PBS液.分别于术后3d、7d利用荧光显微镜观察hAMSCs存活情况,并采用RT-PCR分析损伤脊髓段NGF mRNA、BDNF mRNA及Nogo-A mRNA的表达.结果:术后3d和7d hAMSCs移植组均可观察到植入的hAMSCs在宿主脊髓组织内存活.术后3d、7d,hAMSCs移植组NGF mRNA的表达均高于对照组(P＜0.05,P＜0.01),Nogo-A mRNA的表达均低于对照组(P＜0.05);术后3d时hAMSCs移植组BDNF mRNA的表达与对照组比较无显著性差异(P＞0.05),但术后7d其表达高于对照组(P＜0.05).结论:hAMSCs移植可上调大鼠受损脊髓组织内NGF mRNA和BDNF mRNA的表达、下调Nogo-A mRNA的表达,有利于促进脊髓损伤后的功能修复.     

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.     

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.     

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.     

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.