增殖及非增殖腺病毒载体介导的RNA干扰对肾癌细胞杀伤作用

目的比较荷载Ki67基因小干扰RNA（Ki67-siRNA）的增殖腺病毒ZD55-Ki67及非增殖腺病毒Ad-Ki67对肾癌细胞的杀伤作用。方法MOI=10的ZD55-Ki67、Ad-Ki67感染肾癌786-0细胞，2d后收集细胞，蛋白印迹法检测E1A表达；逆转录-聚合酶链反应（RT-PCR）、蛋白印迹法、免疫细胞化学法检测Ki67表达；原位末端标记法（TUNEL）检测凋亡。4d后噻唑蓝（MTT）法检测细胞存活率，7d后结晶紫染色法检测细胞毒性作用。结果感染ZD55-Ki67的786-0细胞表达E1A，感染Ad-Ki67的细胞不表达E1A。ZD55-Ki67、Ad-Ki67感染的786-0细胞Ki67mRNA表达率分别为（37．9±2．3）％、（64．1±1．9）％；Ki67蛋白表达率分别为（42．5±2．4）％、（60．1±2．2）％；Ki67染色阳性率分别为（20．8±2．8）％、（32．3±2．5）％；786-0细胞存活率分别为（22．2±3．0）％、（60．4±3．4）％；凋亡率分别为（53．0±3．7）％、（35．3±2．5）％，两种病毒处理之间差异均有统计学意义（P〈0．01）。结论ZD55．Ki67抑制786-0细胞Ki67表达及增殖、诱导凋亡及细胞毒性作用均显著优于Ad-Ki67。增殖腺病毒介导的RNA干扰杀伤肾癌细胞作用优于非增殖腺病毒。     

脂质体介导的cFLIP反义寡核苷酸对肾细胞癌的凋亡作用

目的探讨cFLIP反义寡核苷酸（ASODN）对肾细胞癌的抑制作用。方法设计合成cFLIP的ASODN，按不同浓度在脂质体介导下转染786—0肾癌细胞株，设无义（NSODN）和空白对照组进行比较。观察细胞的生长状态，Western blot检测cFLIP蛋白的表达，MTT法检测细胞生长抑制率，应用流式细胞仪检测其凋亡率。结果与NSODN、空白对照组比较，ASODN组cFLIP蛋白表达显著降低（P〈0．05），细胞抑制率（分别为10μmol／L组34．20％，20μmol／L组39．50％）显著增高，上述效应呈浓度依赖性；镜下观察ASODN转染细胞代谢衰退，当转染浓度至20μmol／L时，其凋亡率（56．11％）显著高于空白对照组（7．29％）和NSODN（4．69％）组。结论AS0DN能特异性封闭肾癌细胞cFLIP基因的表达，并可抑制肾癌细胞的增殖，诱导其凋亡。     

survivin反义寡核苷酸诱导胃癌原代细胞凋亡的实验研究

目的探讨survivin反义寡核苷酸对人胃癌原代细胞凋亡的影响，为胃癌的靶向治疗提供实验依据。方法利用人胃癌实体瘤新鲜标本培养胃癌原代细胞，胃癌细胞分为空白对照组、脂质体组、正义寡核苷酸组及反义寡核苷酸转染组。用脂质体介导survivin反义寡核苷酸转染胃癌原代细胞，48h后，观察肿瘤细胞的形态变化，Westernblot检测survivin蛋白的表达，流式细胞术检测细胞的凋亡。结果反义寡核苷酸转染组肿瘤细胞体积变小，细胞碎裂，出现凋亡小体；survivin蛋白量下降；流式细胞术检测到肿瘤细胞的凋亡率增高。与其他各组相比，其差异有统计学意义（P〈0．05），而空白对照组、脂质体组、正义寡核苷酸组之间的差异无统计学意义（P〉0．05）。结论survivin反义寡核苷酸在脂质体介导下转染人胃癌原代细胞，可以诱导肿瘤细胞发生凋亡，抑制细胞生长，反义survivin可能成为一个促进胃癌细胞凋亡的手段。     

联合反义存活素、血管内皮生长因子治疗裸鼠骨肉瘤

目的探讨存活素（Survivin，SVV）、血管内皮生长因子（VEGF）反义寡核苷酸（ASODN）联合治疗裸鼠骨肉瘤。方法构建荷骨肉瘤裸鼠模型，采用瘤内注射给药方式（5mg,／kg体重），以反义SVV、反义VEGF对瘤鼠进行联合干预治疗1周，并与各单药组和空白对照组进行比较，观测各组裸鼠肿瘤生长情况、评估瘤体病理形态，免疫组织化学法检测移植瘤组织SVV、VEGF蛋白表达，DNA末端原位标记法（TUNEL法）检测肿瘤细胞凋亡水平。结果与对照组比较，各治疗组肿瘤生长均不同程度受抑，以联合组最为显著，瘤重仅为（0．52±0．01）g，抑瘤率IR为（42．80±0．88）％；各治疗组肿瘤细胞中SVV、VEGF蛋白表达有所减低，肿瘤细胞出现凋亡坏死改变，其中联合组细胞凋亡指数AI[（27．90±3．66）％]显著高于对照组[（7．10±2．05）％，Χ^2=46．27，P〈0．01]。结论联合应用SVV与VEGFASODN将对裸鼠荷骨肉瘤发挥更强的抗瘤效应。     

hTERT基因短发夹状RNA表达载体对肾癌细胞生长的抑制作用

目的观察针对hTERT基因的短发夹状RNA（shRNA）表达载体pSilencer-hTERT对人肾癌细胞及移植瘤生长的抑制作用。方法（1）pSilencer-hTERT转染人肾癌Kerr-3细胞，1、3、5、7d后逆转录-聚合酶链反应（RT-PCR）、蛋白印迹技术检测hTERTmRNA、蛋白表达，MTT法检测细胞增殖，原位末端标记法检测凋亡。（2）BALB／C-nu裸鼠接种Ketr-3细胞成瘤，瘤内分别注射pSilencer-hTERT（50μg）、空质粒pSilencer1．0-U6（50μg）及等体积（100μg）生理盐水，隔日1次，共7次。治疗结束后第3天处死小鼠，取瘤组织检测肿瘤体积，免疫组织化学染色检测hTERT表达。结果（1）pSilencer-hTERT转染3d后Ketr-3细胞hTERTmRNA表达（43．2±4．4）％、蛋白表达（42．6±5．6）％最低，细胞增殖抑制率（37．3±6．6）％、凋亡细胞阳性率（30．5±4．7）％最高，分别与空质粒对照组[（98．8±4．7）％、（98．0±3．7）％、（3．3±0．9）％、（10．4±2．4）％]比较，差异均有统计学意义（P〈0．01）。（2）pSilencer-hTERT处理组小鼠肿瘤体积（62．4±36．5）mm^3减小，hTERT表达率（65．7±4．7）％降低，分别与空质粒对照组（83．2±38．7）、（90．7±4．2）％比较，差异均有统计学意义（P〈0．05）。结论pSilencer-hTERT能有效、持续抑制人肾癌Ketr-3细胞及裸鼠肾癌移植瘤生长。     

反义Survivin对人结肠癌细胞凋亡及耐药性的影响

目的 观察Survivin ASODN联合长春新碱（VCR）、5-氟尿嘧啶（5-Fu）对人结肠癌细胞系HT-29凋亡的影响。方法 设计合成特异性Survivin反义寡核苷酸（ASODN）。HT-29细胞分成6组：空白对照组、空脂质体转染对照组、正义链转染对照组、100、200、300nmol／L反义链转染组。以阳离子脂质体为载体转染至HT-29细胞内，用Westernblot法检测各组细胞Survivin蛋白表达情况；流式细胞仪检测细胞凋亡情况；MTT法检测VCR、5-Fu对转染前后细胞的生长抑制情况。结果各浓度ASODN转染组癌细胞Survivin蛋白表达有不同程度减少，而各对照组细胞Survivin蛋白表达无明显变化。各ASODN转染组VCR、5-Fu对肿瘤细胞生长抑制率明显高于各对照组（P〈0．05），且300nmol／L转染组明显高于100和200nmol／L组（P〈0．05）。ASODN转染组细胞凋亡指数明显高于各对照组（P〈0．05），以300nmol／L转染组加VCR作用后凋亡指数最高（P〈0．01）。结论Survivin ASODN转染人结肠癌细胞能下调Survivin蛋白的表达，诱导结肠癌细胞凋亡，抑制细胞增值，增加结肠癌细胞对化疗药物的敏感性。     

干扰素-α诱导肾癌细胞胸苷磷酸化酶表达对5-FU化疗敏感性的影响

目的 探讨干扰素-α诱导肾癌细胞胸苷磷酸化酶（thymidine phosphorylase，TP）表达对5-氟尿嘧啶（5-FU）化疗敏感性的影响。方法采用不同浓度的干扰素-α2b处理肾癌细胞株786—0，应用RT—PCR和免疫印迹方法分别检测TP mRNA和TP蛋白水平变化。MTT法检测不同处理组786—0细胞中5-FU的半数抑制浓度（IC50）。建立肾透明细胞癌移植瘤动物模型，观察干扰素-α2b联合5-FU化疗对移植瘤生长的影响，免疫组化检测移植瘤中TP的表达，TUNEL检测肿瘤细胞的凋亡。结果 干扰素-α2b3000和6000IU／ml处理组，TP mRNA表达量（灰度峰值）分别为0．5733±0．0231和0．8233±0．0404，TP蛋白表达量分别为0．6347±0．0719和0．8735±0．0640。干扰素-α对TP的表达有剂量依赖性增强作用（P〈0．01）。在干扰素-α2b作用下，5-FU对786—0半数抑制浓度由（13．9467±3．7140）μmol／L下降至（5．3200±0．1039）μmol／L，化疗敏感性增加（P〈0．01）。联合用药组移植瘤体积为（0．0940±0．0492）cm^3，小于单纯5-FU组的（0．5424±0．1591）cm^3（P〈0．05）。单纯5-FU组和联合用药组移植瘤中肿瘤细胞凋亡指数差异无统计学意义（P〉0．05）。结论 干扰素-α2b诱导的TP增强表达参与了干扰素-α联合5-FU化疗增效作用，TP是干扰素-α2b的靶基因之。     

促凋亡因子Omi/HtrA2对凋亡抑制蛋白表达及A549细胞凋亡的影响

目的观察Omi／HtrA2对凋亡抑制蛋白（XIAP）表达的影响和对肺癌A549细胞凋亡的影响。方法将构建的携带绿色荧光蛋白（GFP）和Omi／HtrA2基因的表达载体（PEGFP-N1-Omi）转染至人肺腺癌A549细胞中，用逆转录-聚合酶链反应（RT-PCR）和Western blot检测Omi／HtrA2对XIAP转录和表达的影响，流式细胞仪检测Oml／HtrA2协同顺铂作用于A549细胞后该细胞的凋亡变化。结果Omi／HtrA2基因转染组XIAP的mRNA表达水平下降37％（P〈0．05），XIAP的蛋白表达水平下降69％（P〈0．05），顺铂诱导后，基因转染组细胞凋亡率为（36．00±1．95）％，显著高于对照组的细胞凋亡率（17．00±1．12）％（P〈0．05）。结论Omi／HtrA2通过抑制XIAP的抗凋亡作用可协同顺铂促进A549细胞凋亡。     

转染人Endostatin基因对胰腺癌SW1990细胞增殖、凋亡及血管内皮生长因子表达的影响

目的观察转染人Endostatin（hEndostatin）基因对胰腺癌细胞株SW1990增殖、凋亡及血管内皮生长因子（VEGF）表达的影响。方法携带hEndostatin基因的复制缺陷型重组腺病毒载体体外转染SW1990细胞，MTT法检测细胞增殖，流式细胞仪检测细胞凋亡，实时荧光定量PCR和ELISA分析检测hEndostatin和VEGF的表达。建立裸鼠胰腺癌模型，随机分为3组（n=8），瘤体内分别注射磷酸盐缓冲液（PBS组）、报告基因LacZ重组腺病毒（Ad—LacZ组）、hEndostatin重组腺病毒（Ad—bEnd组）100山，隔日1次，共4次。4周后免疫组织化学染色检测肿瘤组织中hEn．dostatin、VEGF、增殖性细胞核抗原（PCNA）的表达，TUNEL法检测肿瘤细胞凋亡。结果体外转染hEndostatin基因不影响SW1990细胞的增殖和凋亡（P〉0．05），但下调VEGF的表达（P〈0．01），下调作用第5天最大，在mRNA和蛋白水平的抑制率分别为84．67％和81．41％。体内转染4周后，Ad．bend组VEGF、PCNA阳性表达率分别为（36．3±7．1）％、（38．2±3．9）％，显著低于Ad．LacZ组的（81．2±6．6）％、（93．2±4．9）％和PBS组的（78．4±6．2）％、（90．1±5．7）％（P〈0．01）；肿瘤细胞凋亡率为（31．2±5．4）％，显著高于Ad—LacZ组的（9．4±4．9）％和PBS组的（8．5±3．7）％（P〈0．01）。结论hEndostatin基因转染抑制SW1990细胞的体内增殖并促进凋亡；下调SW1990细胞内源性VEGF的表达可能是抗肿瘤的作用机制之一。     

反义调控DNA甲基转移酶1基因对人胆管癌细胞生长的抑制效应

目的观察转染反义DNMT1基因真核表达载体对人胆管癌细胞QBC-939生长的影响,初步探讨DNMT1基因在胆管癌发生中的表遗传学机制。方法将构建好的反义DNMT1基因真核表达载体用脂质体介导法转入人胆管癌细胞QBC-939,Western blot检测转染前后DNMT1蛋白的表达变化,MTT法和软琼脂克隆形成试验观察各组细胞的生长增殖能力,流式细胞术观察细胞生长周期及凋亡率的变化。结果（1）Western blot检测证实转染反义基因能使DNMT1蛋白表达水平降低;（2）转染反义DNMT1基因能抑制QBC-939的生长曲线,并使其软琼脂克隆形成率从（38．020±4．120）％减少至（14．860±2．129）％,差异有显著性意义（P=0．000）;（3）转染反义DNMT1基因能影响QBC-939的细胞周期,使之阻滞于G1期,细胞凋亡率从（1．63±0．27）％增加到（6．19±0．78）％,差异亦有显著性意义（P=0．000）。结论通过转染反义DNMT1基因真核表达载体,可下调DNMT1在QBC-939细胞中的表达水平,并能抑制胆管癌细胞的生长和增殖,促进凋亡的发生,提示DNMT1可能通过甲基化途径与胆管癌的发生有关。     

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.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

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.