经皮选择性肝脏隔离灌注化疗肝细胞形态及凋亡研究

目的探讨经皮选择性肝脏隔离灌注化疗（PSIHP）的可行性及隔离效果。方法实验猪8头，利用介入放射学方法进行经皮选择性肝脏隔离灌注化疗结合血液灌流。化疗药物选用5-Fu。比较灌注及未灌注区域肝细胞形态和凋亡指数。结果灌注区域肝细胞损伤明显，肝细胞凋亡指数（52．83±5．12）明显高于未灌注区域肝细胞凋亡指数（3．52±0．96）（P〈0．01）。结论PSIHP是一种简单有效的肝脏隔离灌注化疗技术，隔离效果佳，对未灌注区域肝组织有良好的保护作用。     

新型双球囊导管经皮选择性隔离肝脏灌注化疗的效果研究

目的探讨自制双球囊导管经皮选择性隔离肝脏灌注化疗的隔离效果。方法12只成年猪随机分为两组：HAI组6头,进行常规经肝动脉灌注化疗;PSIHP组6头,利用自制双球囊导管经介入放射学方法行经皮选择性隔离肝脏灌注化疗结合血液灌流。化疗药物选用5-FU,分别检测肝静脉及外周血液中的血药浓度峰值,了解球囊隔离肝脏效果。结果HAI组肝静脉血和外周静脉血浓度峰值分别为4658.420±433.204mg/L和1676.140±226.933mg/L,PSIHP组为5321.711±517.318mg/L和65.735±6.425mg/L。两组外周静脉血浓度峰值有显著性差异（P〈0.01）。结论自制新型双球囊导管能有效隔离肝脏,是一种理想的隔离肝脏灌注化疗的球囊导管。     

经肝动脉区域肝脏隔离灌注的研究

目的　研究幼猪经肝动脉区域隔离肝灌注的效果。　方法　14只幼猪随机分为2组:对照组(7只):采用经肝动脉灌注;实验组( 7只):左肝动脉及左肝静脉插管,进行左肝区域隔离肝灌注。灌注液为氨甲喋呤溶液(1mg/kg), 灌注时间为60min。于灌注5、10、20、30、45、60min时分别抽取外周血、肝脏灌注区域血、肝脏未灌注区域血(实验组)测定血药浓度; 灌注后切取左肝及右肝组织进行病理检查。　结果　在所有时间点, 实验组肝脏灌注区域氨甲蝶呤的血药浓度明显高于非灌注区和外周血(P<0. 01), 60min时最高, 达( 40. 211±3. 756 )μg/ml, 而非灌注区和外周血中仅为(1. 584±0. 347)μg/ml和(0. 773±0. 096)μg/ml。实验组灌注区域血药浓度均高于对照组肝脏血药浓度(P<0. 01), 60min时分别达(40. 211±3. 756)μg/ml和(4. 498±1. 643)μg/ml。实验组灌注区浓度-时间曲线下面积为218. 295μg/ml,而在对照组肝脏仅为260. 860μg/ml。病理检查提示两组灌注肝脏均有肝细胞浊肿、气球样细胞,但实验组肝脏灌注区域肝细胞坏死率为85. 7% (6 /7),明显高于对照组28. 6% (2 /7)。实验组肝脏未灌注区域无明显病理损害。　结论　动物实验证实经肝动脉区域隔离肝灌注是一种灌注及隔离效果好、肝功能损害小的区域化疗方法。     

介入性球囊导管技术在肝脏隔离灌注中应用的动物实验研究

肝脏隔离灌注 (ｉｓｏｌａｔｅｄｌｉｖｅｒｐｅｒｆｕｓｉｏｎ ,ＩＬＰ)是将肝脏所属主要血管游离阻断 ,并通过门静脉和(或 )肝动脉对肝脏进行隔离灌注。为了使技术简便易行 ,我们采用一种介入性球囊导管辅助隔离技术进行家猪的原位肝脏隔离灌注 ,现报告如下。1.材料与方法 :实验动物 :为健康家猪 12头 ,体重 2 3～ 35ｋｇ ,平均 2 8 9ｋｇ ,雌雄不限。主要试剂及仪器包括ＭｉｔｏｍｙｃｉｎＣ ,岛津ＬＧ 6Ａ型高效液相色谱等。随机分成 2组 ,Ａ组 (6只 ) :采用传统手术方法进行原位肝脏隔离灌注 ;Ｂ组 (6只 ) :采用球囊导管隔离技术进行灌…     

经皮选择性肝脏隔离灌注化疗的实验研究

目的探讨经皮选择性肝脏隔离灌注化疗的可行性及隔离效果。方法将12只猪随机分为两组:HAI组6头,进行常规经肝动脉灌注化疗;PSIHP组6头,利用介入放射学方法进行经皮选择性隔离肝脏灌注化疗结合血液灌流。化疗药物选用5-FU。分别检测肝静脉及外周血液中的血药浓度,并对肝组织行病理学检查。结果HAI组右肝静脉血和外周静脉血浓度峰值分别为(4082.530±415.213)mg/L,(1682.230±216.834)mg/L;PSIHP组右肝静脉血、外周静脉血血药浓度峰值分别为(5321.711±517.318)mg/L,(510.834±52.518)mg/L。两组间有显著性差异(P<0.01)。PSIHP组过滤后肝静脉血血药浓度峰值为(1192.063±114.864)mg/L,碳肾率过滤达到(77.6±0.9)%。PSIHP组灌注区域肝脏组织损害程度比HAI组大。结论PSIHP是一种简单有效的肝脏隔离灌注化疗技术,与常规经肝动脉灌注化疗相比,不仅可以增加局部血药浓度,更可以降低外周的血药浓度,降低毒副作用。     

FK506对肝脏保存再灌注中Bcl-2 mRNA、Bax mRNA表达及肝细胞凋亡的影响

目的探讨肝脏保存再灌注中Bcl-2 mRNA、Bax mRNA表达,肝细胞凋亡以及FK506的作用.方法建立离体大鼠肝脏保存再灌注模型,采用逆转录-多聚酶链反应(RT-PCR)和细胞凋亡原位末端标记技术(TUNEL),分别检测肝脏保存0、8、16、24、32 h组Bcl-2 mRNA、Bax mRNA表达,肝细胞凋亡以及FK506对上述指标的影响.结果 FK506保存组16、24、32 h Bcl-2 mRNA表达明显高于对照组(P<0.05); Bax mRNA表达明显低于对照组(P<0.05);FK506保存组肝细胞凋亡指数明显低于对照组(P<0.05).结论 FK506能使肝脏保存再灌注中Bcl-2 mRNA表达增强,Bax mRNA表达减低,肝细胞凋亡减少.FK506对肝脏保存再灌注损伤具有防治作用.     

低氧诱导因子-1α和p53在肝脏低氧损伤中的作用

目的:探讨低氧诱导因子-1α(HIF-1α)、p53及细胞凋亡在大鼠肝脏低氧损伤中的作用。方法:雄性SD大鼠64只,随机分为对照组和肝动脉结扎组(n=32)。各组均行剖腹、肝脏骨骼化及肝素林格液肝脏灌注,肝动脉结扎组行肝动脉结扎术。术后1、3、7、14d留取肝脏组织及血标本。采用反转录-聚合酶链反应(RT-PCR)法检测肝脏组织HIF-1αmRNA表达水平;免疫组织化学方法检测肝脏组织HIF-1α及p53蛋白表达水平;TUNEL法检测肝细胞凋亡。自动生化分析仪检测血清丙氨酸转氨酶(ALT)活性以评价肝损伤。结果:肝动脉结扎后肝组织HIF-1αmRNA及HIF-1α蛋白较对照组明显增高,分别于结扎后3d和7d达峰值[0.834±0.129比0.372±0.048,(7.8±3.1)%比(2.1±1.7)%,P均<0.01]。肝动脉结扎组肝细胞p53均明显高于对照组(P<0.05或P<0.01),于术后7d达峰值[(41.2±9.1)%比(5.2±4.3)%,P<0.01]。肝动脉结扎组肝细胞凋亡指数均明显高于对照组(P<0.05或P<0.01),于术后7d达峰值[(21.3±7.4)%比(3.7±3.5)%,P<0.01]。肝动脉结扎组ALT水平均明显高于对照组。HIF-1α、p53蛋白表达及凋亡细胞都主要位于肝小叶中央静脉周围。结论:HIF-1αmRNA表达增加、HIF-1α蛋白积聚以及p53促凋亡途径的激活在肝脏低氧损伤中可能发挥重要作用。     

低温保存-再灌注肝脏肝细胞凋亡与肝细胞糖原含量的关系及bax基因在其中的作用

目的　研究肝脏低温保存 再灌注期间肝细胞糖原含量与肝细胞凋亡之间的关系及bax基因在其中的作用。方法　制备糖原含量显著不同的 4组兔肝脏模型 ,根据给食方法的不同分为A组 (禁食 2 4h ,但自由饮水 )、B组 (标准实验室饮食 )、C组 (标准实验室饮食 +每 6h静脉滴注 2 5 %葡萄糖 3 0ml)及D组 (标准实验室饮食 +每 4h静脉滴注2 5 %葡萄糖 3 0ml) ,检测各组肝脏低温保存 再灌注期间肝细胞凋亡及bax基因蛋白的表达情况。结果　各组肝脏于低温保存 9h后再灌注 60min时 ,肝组织内可见明显的肝实质细胞凋亡现象 ,A、B、C、D 4组的凋亡细胞数量依次减少 ,4组间两两比较差异有统计学意义 ,各组肝细胞bax基因蛋白的表达程度与肝细胞糖原含量有密切的相关性。结论　肝脏低温保存 再灌注过程中 ,肝细胞内糖原能明显拮抗肝实质细胞凋亡的发生 ,其内在机理可能为肝细胞糖原通过抑制bax基因蛋白的表达从而达到拮抗肝实质细胞凋亡的发生。     

大鼠肝脏缺血再灌注时肝细胞凋亡与肿瘤坏死因子-α的关系

目的探讨大鼠肝脏缺血再灌注时肝细胞凋亡与肿瘤坏死因子-α(TNF-α)的关系。方法建立大鼠局部肝脏缺血再灌注模型,将72只健康雄性Wistar大鼠随机分为正常组、假手术组和缺血再灌注组,采用放射免疫法测定再灌注后不同时相中血清TNF-α含量,末端脱氧核苷酸转移酶介导的dUTP缺口末端标记法(TUNEL)和透射电镜观察肝细胞凋亡状态。结果再灌注后1、3、6h和24h血清TNF-α含量及肝细胞凋亡指数(HAI)明显高于正常组和假手术组,且均于6h达到高峰,再灌注后各时相TNF-α水平与HAI呈显著正相关。结论肝脏缺血再灌注损伤过程中,TNF-α表达水平异常上调并可能对肝实质细胞凋亡起介导作用。     

区域性动脉灌注化疗对胰腺癌bcl-2、bax基因的影响

目的　探讨区域性动脉灌注化疗对胰腺癌bcl-2、bax基因表达的影响,寻找胰腺癌治疗的新手段。方法　应用TUNEL法检测32例未经区域性动脉灌注化疗和19例经区域性动脉灌注化疗的胰腺癌细胞凋亡指数(AI);并采用免疫组织化学方法检测区域性动脉灌注化疗对胰腺癌细胞bcl、bax基因表达的影响。结果　区域性动脉灌注化疗组胰腺癌细胞AI比未区域性动脉灌注化疗组明显升高(0.65%vs1.10%,P＜0.05);与未区域性动脉灌注化疗组相比,区域性动脉灌注化疗组肿瘤细胞bcl-2基因表达明显减少(36.7%vs75.0%,P＜0.05),而bax基因的表达显著增加(73.6%vs34.0%,P＜0.05)。结论　区域性动脉灌注化疗可以诱导胰腺癌肿瘤细胞凋亡的增加,是胰腺癌综合治疗的有效措施之一。     

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.