雷帕霉素对人肝癌裸鼠原位移植瘤生长的影响

目的：探讨免疫抑制剂雷帕霉素对肝癌细胞生物学行为的影响。方法：建立肝癌裸鼠原位移植瘤模型80只,随机分为空白对照组、环孢霉素(CsA)处理组、雷帕霉素常规剂量处理组和高剂量处理组,每组20只。用药2周后观察肿瘤生长情况,RT-PCR方法检测肿瘤组织中CD44v6 mRNA的表达。结果：雷帕霉素常规剂量组及高剂量组肿瘤体积较空白对照组明显缩小, CD44v6的表达显著下调(P<0.05);CsA组肿瘤体积较之空白对照组明显增大, CD44v6的表达显著上调(P<0.05)。结论：CsA可促进肝癌的生长和转移;雷帕霉素具有显著抑制肝癌侵袭转移的作用,能抑制肝癌细胞CD44v6基因的表达。     

雷帕霉素对人肝癌裸鼠皮下移植瘤生长的抑制作用

目的 探讨雷帕霉素对人肝癌裸鼠皮下移植瘤生长的影响及机制.方法 建立人肝癌裸鼠皮下移植瘤模型24只,随机分为对照组、RAPA小剂量组(每日1 mg/kg体重)、RAPA大剂量组(每日5 mg/kg体重).用药4周后观察肿瘤体积和重量、肿瘤组织切片行透射电镜检查、荧光定量聚合酶链反应(PCR)法检测肿瘤的血管内皮生长因子(VEGF)、基质金属蛋白酶2(MMP-2)mRNA的表达,酶联免疫吸附试验(ELISA)法测定裸鼠血VEGF、MMP-2浓度.结果 与对照组比较,雷帕霉素小剂量组和大剂量组均能抑制肿瘤生长[(0.42±0.17)cm3和(0.38±0.21)cm3比(0.78±0.25)cm3,P＜0.05];VEGF mRNA、MMP-2 mRNA的转录和翻译显著减少(P＜0.01).结论 雷帕霉素可以通过抑制肝癌细胞VEGF和MMP-2的mRNA转录和蛋白表达,抑制肿瘤生长,但不呈剂量依赖性.     

雷帕霉素在人肝癌裸鼠肝移植瘤血管形成和肿瘤进展中的作用

目的 探讨雷帕霉素(RPM)在人肝癌裸鼠肝移植瘤血管形成和肿瘤发展中的作用.方法 建立人肝癌裸鼠肝移植瘤模型,使用RPM、环孢素A(CsA)进行干预治疗,采用实时定量PCR法检测移植瘤血管内皮细胞生长因子(VEGF)mRNA的表达,免疫组织化学方法和图像分析技术检测移植瘤VEGF蛋白、增殖细胞核抗原(PCNA)的表达和微血管密度(MVD),ELISA法检测外周血VEGF蛋白水平的变化.结果 (1)RPM、CsA和对照组移植瘤重量分别为(372±35)mg、(769±39)mg、(751±42)mg;RPM组移植瘤重量较对照组显著减少(P<0.01);CsA组和对照组比较无明显变化(P>0.05).(2)RPM组移植瘤VEGF mRNA、蛋白和PCNA的表达及外周血中VEGF蛋白水平较对照组显著下调(P<0.05),CsA组和对照组比较无明显差异(P>0.05).(3)RPM组移植瘤MVD较对照组显著减少(P<0.01);CsA组和对照组相比无明显变化(P>0.05).结论 RPM通过阻止肿瘤增殖,下调VEGF的表达,抑制肝癌血管形成和肿瘤进展.     

免疫抑制剂对肝癌细胞增殖、运动侵袭的影响

目的探讨免疫抑制剂对肝癌细胞增殖、运动侵袭能力的影响,为肝癌肝移植术后免疫抑制剂的选用提供指导。方法用裸鼠人高转移肝癌模型LCI-D20,研究环孢素A(CsA)、他克莫司(FK506)、雷帕霉索(RPM)对肿瘤生长及自发肺转移的影响。采用扫描电镜、噻唑蓝比色法 (MTT)、流式细胞仪、Boyden小室等方法分别研究各免疫抑制剂对人肝癌高转移细胞株 MHCC97H增殖、凋亡、细胞周期、运动及侵袭的影响。结果体内实验中,RPM抑制了LCI-D20 模型移植瘤的生长[(0．76±0．38)g vs(2．09±0．75)g,P<0．05]及肺转移的发生(2／7 vs．7／7, P<0．05);CsA组肺部转移灶的数目明显多于对照组(6±2 vs．4±1,P<0．05);FK506组肺转移发生率虽较对照组减少,但差异无统计学意义。CsA及FK506均对移植瘤的生长无影响。体外实验中,RPM抑制了MHCC97H增殖,并使细胞周期停滞于G_0-G_1期。RPM及FK506抑制了 MHCC97H的运动、侵袭(P<0．05),而CsA则促进了MHCC97H的运动、侵袭(P<0．05)。结论 CsA促进了肝癌的转移;FK506不促进肝癌的转移;而RPM则抑制了肝癌细胞的增殖及转移。     

Angiostatin基因治疗人肝癌裸鼠移植瘤的实验研究

目的:研究Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的抑制作用及其相关机理。方法:使用人原发性肝癌细胞株SMMC-7721建立人肝癌裸鼠皮下移植瘤动物模型,质粒用脂质体DOTAP介导转染细胞。将荷瘤裸鼠随机分为两组,分别注射质粒PcDNA3、Angiostatin/PcDNA3,观察两组动物的肿瘤生长曲线,检测肿瘤的Angiostatin、VEGF、HIF-1α表达和微血管密度(MVD),利用TUNEL染色法行原位细胞凋亡分析。结果:Angiostatin基因治疗在早期具有抑制肿瘤生长的作用,大约1周后肿瘤以更快的速度生长并迅速赶上空质粒对照组肿瘤;Angiostatin基因治疗组的肿瘤组织中有An-giostatin的局部高表达,MVD(24.8±2.8)低于空质粒对照组(30.2±4.1)(P〈0.05)。肿瘤组织中HIF-1α蛋白局部高表达,VEGF表达高于空质粒对照组,细胞凋亡指数(2.87±0.48)高于空质粒对照组(1.55±0.43)(P〈0.01)。结论:Angiostatin基因治疗对人肝癌裸鼠皮下移植瘤的生长具有一定的抑制作用,肿瘤对Angiostatin基因治疗可以产生耐受性。     

普乐可复在异种小肠移植中的作用

目的探讨免疫抑制剂普乐可复(FK506)对于异种小肠移植后迟发异种移植物排斥反应和细胞介导的异种移植物排斥反应的作用。方法采用仓鼠-大鼠动物实验模型,分为对照组和治疗组。治疗1组为单纯用FK506组;治疗2组为FK506加脾切除组。观察移植肠管吸收功能、体重、生存时间、FK506血药浓度及移植肠管苏木精-伊红染色。结果治疗1、2组的生存时间分别为(29.5±2.4)d和(106.6±26.3)d,与对照组(4.3±0.5)d相比显著延长(P<0.01);且治疗1、2组之间相比,差异亦有非常显著性意义(P=0.006)。术后第4d对照组苏木精-伊红染色可见绒毛萎缩,有大量炎性细胞浸润。治疗组小肠黏膜显示高分泌状态。术后126d治疗2组小肠肌层明显增厚、绒毛萎缩、肠壁小动脉壁纤维化。结论FK506可抑制异种小肠移植后迟发异种移植物排斥反应和细胞介导的异种移植物排斥反应;加脾切除可明显延长异种小肠移植的存活时间;但不能逆转异种小肠移植后所发生的慢性排斥反应。     

mTOR信号转导通路在自体移植静脉中的表达及意义

目的研究哺乳类动物雷帕霉素靶蛋白(mTOR)在自体移植静脉中表达的动态变化规律。方法Wistar大鼠64只,建立自体静脉移植模型,随机分为8组,分别在移植后6 h,1、3 d,1、2、4、6、8周切取移植静脉。逆转录PCR结合原位杂交研究移植血管中mTOR的tuRNA表达,Western blot联合免疫组化检测mTOR蛋白产物表达的变化,同时检测增殖细胞核抗原(PCNA)。结果逆转录PCR扩增在静脉移植1-3 d即出现mTOR mRNA表达增强,1-2周达到高峰,表达值分别为(48±18)％和(33±11)％,与其他组比较差异有统计学意义(P<0．01),6-8周逐渐恢复正常。免疫组化及Western蛋白印迹均提示mTOR蛋白在移植3 d表达明显增多,2-4周达到高峰,分别为(29±8)％和(31±6)％,与其他组比较差异有统计学意义(P<0．01),8周恢复至正常水平。mTOR蛋白产物表达与PCNA表达呈正相关(r=0．756,P<0．01)。结论mTOR在血管移植后的过程中被激活,与内膜增生关系密切,可能是防治移植血管狭窄、闭塞的干预靶点。     

重组人内皮抑素联合应用5氟脲嘧啶对胃癌裸鼠移植瘤的影响

目的探讨重组人内皮抑素(recombinant human endostatin,rhES)与5氟脲嘧啶(5-fluorouracil,5-FU)联合应用对胃癌裸鼠移植瘤生长的抑制作用.方法建立胃癌异位移植BALB/C裸鼠模型,分为4组,每组6只.分别注射生理盐水,腹腔内注射5-FU(10 mg/kg),rhES组瘤周注射rhES(2 mg/kg)同时给予5-FU与rhES,每天1次,连用10 d.计算肿瘤体积、抑瘤率及肿瘤缩小率,检测肿瘤组织血管内皮生长因子(VEGF)、碱性成纤维生长因子(bFGF)、血管内皮生长因子-C(VEGF-C)、Ⅷ因子相关抗原(FⅧAg)、增殖细胞核抗原(PCNA)、bcl-2表达及肿瘤细胞凋亡指数(AI).结果rhES+5-FU组肿瘤体积为(43±2)mm3,5-FU组为(169±45)mm3,rhES组为(95±28)mm3,对照组为(1057±114)mm3(P＜0.01).抑瘤率为99.6%,肿瘤缩小率为98.2%.用药前rhES+5-FU组肿瘤体积为(207±50)mm3,比5-FU组与rhES组下降更迅速(P＜0.01).rhES+5-FU组与5-FU组VEGF、bFGF及VEGF-C表达强度均为0～+;rhES+5-FU组PCNA及bcl-2表达最弱;rhES+5-FU组AI为11.7±1.1,5-FU组为6.2±0.6,rhES组为5.8±0.8,对照组为2.4±0.6(P＜0.01).微血管密度在rhES+5-FU组为8.9±2.5,rhES组为10.0±1.5,均低于5-FU组(27.3±1.7)与对照组(29.9±2.3)(P＜0.01).结论联合应用5-FU及rhES能显著抑制胃癌血管生成,增加肿瘤细胞凋亡,使胃癌裸鼠移植瘤的肿瘤体积明显缩小.     

乙型肝炎病毒x蛋白促进裸鼠人肝癌模型的VEGF表达

目的探讨乙型肝炎病毒x蛋白(HBx)促进肝癌细胞增殖的作用机制。方法将编码HBx基因全长的表达质粒pHA-HBx转染肝癌HepG2细胞,用G418筛选阳性克隆;采用逆转录聚合酶链反应(RT-PCR)鉴定HBx基因在HepG2细胞基因组的整合;分别用转染HBx基因前后的细胞建立肝癌裸鼠模型,观察两组裸鼠肿瘤组织生长增殖状况;采用免疫组织化学染色方法检测两组裸鼠肿瘤组织中VEGF的表达。结果 HBx基因成功整合入肝癌HepG2细胞基因组;转染HRx基因前后的两组HepG2细胞在裸鼠体内的接种成瘤率均为100％;转染HBx基因的肿瘤生长速度较未转染组明显加快;接种8周后,转染组肿瘤体积(2．86±0．34)cm3,未转染组为(2．48±0．22)cm3,两组间差异有统计学意义(t=1．905,P<0．05);转染组肿瘤组织中VEGF的表达较对照组明显增强(x2= 7．66,P<0．01)。结论 HBx可促进裸鼠肝癌组织VEGF表达,增加肝癌细胞的增殖活性,加速肿瘤组织生长。     

抗肿瘤血管形成剂抑制肝癌生长及转移的实验研究

目的　研究α干扰素 (IFN α)对肝癌生长及转移的抑制作用及其是否通过抑制一氧化氮合酶 (Ⅱ型 ,iNOS)和血管内皮生长因子 (VEGF)进而减少肝癌血管形成起作用。方法　应用裸鼠人肝癌转移模型LCI D2 0 ,于肿瘤移植后第 2天每只开始皮下注射不同剂量IFN α(3× 10 5U/d ,6×10 5U/d) ,每天 1次 ,对照组注射相同体积的生理盐水。每组治疗 35d后处死部分裸鼠 ,测量移植瘤大小 ,观察肺转移情况 ;剩余裸鼠继续用药观察IFN α对其生存时间的影响。LCI D2 0肿瘤组织移植到裸鼠角膜建立角膜微囊移植模型 ,检测IFN α对肝癌肿瘤血管形成的抑制作用。免疫组织化学方法检测治疗前后肝癌组织iNOS ,VEGF及肿瘤微血管密度变化。结果　对照组裸鼠肺转移率为10 0 % (10 /10 ) ,移植瘤大小为 8475± 2 6 36mm3,生存时间为 45± 4d ;IFN α 3× 10 5U/d治疗组分别为 5 0 % (4/8)、76 9± 2 87mm3 和 81± 6d ,与对照组比较移植瘤大小及生存时间差别有统计学意义 (P<0 0 1) ;而二者之间肺转移率无统计学差别 (P >0 0 5 ) ;IFN α 6× 10 5U/d治疗组则分别为 0 (0 /8)、13± 9mm3 和 10 5± 2 4d ,与对照组比较差别有统计学意义 (P <0 0 1)。应用裸鼠角膜微囊移植模型检测LCI D2 0肝癌组织有较强的诱导肿瘤血管形成的效应     

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 comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.