纤维连接蛋白及精-甘-天冬-丝氨酸多肽对肝癌细胞化疗敏感性的影响

目的 探讨纤维连接蛋白(FN)和精-甘-天冬-丝氨酸多肽(RGDS多肽)对肝癌细胞化疗敏感性的影响.方法 将肝癌细胞株7721分为胎牛血清BSA处理组(BO组)、纤维连接蛋白FN处理组(FO组)、精-甘-天冬-丝氨酸RGDS多肽处理组(RO组)、FN+RGDS多肽共同处理组(FR组),加入不同浓度的丝裂霉素C(MMC)作用2 h、12 h和24 h,用MTT比色法检测不同时间肿瘤细胞的存活率,用荧光染色法和流式细胞术检测肿瘤细胞凋亡,比较FN和RGDS对化疗作用结果的影响.结果 不同浓度MMC作用2 h后,FO组及BO组、FO组与FR组之间的存活率比较,差异无统计学意义(P＞0.05),而作用12 h、24 h后,FO组及BO组、FO组与FR组之间的存活率比较,差异有统计学意义(P＜0.05).结论 药物作用一定时间后,FN能使MMC对肝癌细胞的促凋亡作用下降,产生药物耐受;而RGDS多肽上调肿瘤细胞对化疗药物的敏感性.     

肿瘤坏死因子相关诱导凋亡配体联合化疗药物治疗膀胱癌的研究

目的　探讨肿瘤坏死因子相关诱导凋亡配体 (TRAIL)治疗膀胱肿瘤的作用 ,以及与化疗药物的协同作用。方法　将T2 4及 5 63 7膀胱肿瘤细胞接种至 96孔培养板后分别加入浓度为1、10、10 0 μg/L的TRAIL ,0 .1、1.0、10 .0mg/L的阿霉素 (ADM )和丝裂霉素 (MMC) ,不同浓度的TRAIL、ADM、TRAIL和MMC ,噻唑蓝比色 (MTT)法分别检测肿瘤细胞的生存率。将膀胱肿瘤细胞接种至 12孔板 ,培育 2 4h后加入不同浓度的TRAIL、ADM、MMC、TRAIL联合ADM、MMC。用流式细胞术检测不同处理组肿瘤细胞的凋亡率和死亡率。结果　 10 0 μg/LTRAIL引起T2 4、5 63 7细胞的凋亡率分别为 2 0 .1%、45 .3 % ,与无药物组 1.1%、3 .5 %的凋亡率比较差异有非常显著性(P <0 .0 1)。单独运用 10mg/LMMC、ADM对T2 4、5 63 7的抑制率分别为 3 6.0 %、44 .1%、2 6.7%、3 0 .2 % ;而 10 0 μg/LTRAIL和 10mg/LMMC、ADM联合后对T2 4、5 63 7的抑制率分别达到 5 8.4%、73 .7%、90 .7%、88.2 % ,两者有明显的协同作用 (P <0 .0 5 )。结论　在体外实验中 ,TRAIL可通过诱导肿瘤细胞的凋亡而产生抗膀胱肿瘤的作用 ;TRAIL与化疗药物ADM、MMC有协同抗肿瘤作用     

丝裂霉素对膀胱癌EJ细胞作用机制的研究

目的　从诱导坏死和凋亡角度探讨丝裂霉素 (MMC)对膀胱癌EJ细胞的作用机制。　方法　将不同浓度的MMC作用于膀胱癌EJ细胞 ,在不同时间内采用流式细胞术 (FCM )和 3’末端脱氧核苷酸转移介导生物素 (TUNEL)及伊红排斥实验检测EJ细胞的凋亡情况和对其的杀伤作用。　结果　不同浓度的MMC在 2 4h内可以持续诱导EJ细胞凋亡 ,MMC 0 .1mg/ml组 2 4h时凋亡率为 71% ,对EJ细胞的杀伤作用与剂量呈正比。　结论　MMC对膀胱癌EJ细胞的抑制作用是通过促凋亡机制和促坏死机制完成的     

人类重组肝细胞生长因子影响膀胱癌细胞株生长和抑制丝裂霉素C诱导细胞凋亡的研究

目的 :观察人类重组肝细胞生长因子 (rhHGF)对膀胱移行细胞癌T2 4细胞增殖和丝裂霉素C(MMC)诱导的细胞凋亡的影响。方法 :以T2 4细胞为研究材料 ,用不同浓度rhHGF干预T2 4细胞生长及MMC诱导的细胞凋亡作用。利用MTT实验、流式细胞仪技术来判定rhHGF对细胞增殖和凋亡的影响。结果 :不同浓度rhHGF组间 ,T2 4相对增殖细胞数差异无统计学意义 (P >0 .0 5 ) ;rhHGF预处理后 ,MMC诱导的T2 4细胞凋亡率明显下降 ,在一定范围内有量效关系。结论 :HGF并不显著诱导T2 4细胞增殖 ,而一定剂量范围内的HGF能抑制MMC诱导的细胞凋亡 ,可能与膀胱癌的复发、耐药等临床特性有关     

人工合成拟Smac融合多肽促低剂量丝裂霉素C诱导膀胱癌细胞凋亡的研究

目的:探讨人工合成拟Smac融合多肽(SmacN7)对低剂量丝裂霉素C(MMC)诱导的膀胱癌T24细胞凋亡的促进作用.方法:运用固相多肽合成技术人工合成SmacN7细胞可穿透性融合多肽,将0.05mg/mlMMC诱导的膀胱癌T24细胞与50～500 μg/L的SmacN7融合多肽共同孵育4～48 h,采用Annexin-V荧光染色技术检测肿瘤细胞凋亡情况;应用流式细胞术和MTT比色法检测诱导后T24细胞凋亡率、增殖抑制率与SmacN7的时间和浓度的效应关系.结果:50～500 μg/L SmacN7作用4～48 h,肿瘤细胞出现典型的凋亡形态学改变,随着SmacN7浓度的增加或药物作用时间的延长,肿瘤细胞凋亡率也增加,12 h为5.67%～56.12%,24 h为14.54%～65.24%,48 h为31.48%～87.23%,同时细胞增殖抑制率出现明显增加,药物作用12 h、24 h、48 h后,增殖抑制率分别为9.58%～63.42%、28.94%～72.3%、44.7%～87.12%.结论:SmacN7能够有效地促进低剂量MMC诱导的膀胱癌T24细胞凋亡,并具有时间和浓度依赖性,为膀胱肿瘤的生物治疗提供了新思路.     

阿霉素联合4-羟苯维胺酯对膀胱癌细胞生长抑制与凋亡的影响

目的　通过观察盐酸阿霉素 (ADM )联合 4 羟苯维胺酯 (HPR )对人膀胱移行癌细胞的生长抑制和诱导凋亡作用 ,探讨两药对膀胱行癌细胞是否存在协同作用。方法　应用四甲基偶氮蓝比色 (MTT)法检测 0 .0 5mg/L阿霉素及 10 -6、5× 10 -6、10 -5mol/L不同浓度 4 HPR对膀胱癌细胞株T2 4的细胞毒作用 ,应用流式细胞仪检测 4 HPR、阿霉素或两药联合应用时对T2 4细胞生长抑制率。结果　单用 5 μmol/L的 4 HPR、0 .0 5mg/L阿霉素诱导T2 4细胞凋亡率分别为 8%和 2 1% ,两药联合后凋亡率达 5 2 % (P <0 .0 5 )。 0 .5mg/L阿霉素对T2 4细胞凋亡率为 5 2 % ,联合1、5 μmol/L的 4 HPR后凋亡率上升至 81%和 94% (P <0 .0 5 )。 结论　 4 HPR能诱导T2 4细胞凋亡 ,存在浓度和时间依赖性 ,4 HPR与阿霉素联合用药对膀胱癌细胞有明显生长抑制和凋亡诱导的协同作用 ,能缩短产生抑瘤效果的作用时间 ,减少阿霉素的用量。     

半胱氨酸蛋白酶32在丝裂霉素C诱导膀胱癌细胞凋亡中的作用

目的　探讨半胱氨酸蛋白酶 32 (caspase 3)在丝裂霉素C(MMC)诱导膀胱癌EJ细胞凋亡中的作用。　方法　采用末端脱氧核苷酸转移酶介导生物素标记法 (TUNEL)和流式细胞术 (FCM)研究EJ细胞凋亡及细胞周期变化 ,分析caspase 3抗体对低剂量MMC诱导EJ细胞凋亡的影响。　结果　TUNEL法显示MMC组EJ细胞出现细胞凋亡特有的形态学特征 ,凋亡指数 (6 2 .9± 2 .2 ) % ,较cas pase 3抗体加MMC组 (4.9± 0 .3) %和空白组 (2 .7± 0 .7) %显著增高 (P <0 .0 0 1)。FCM检测结果明 ,MMC主要诱导G0 /G1期细胞凋亡而出现凋亡峰 ,凋亡率 2 6 .0 6 % ;caspase 3抗体能特异性抑制MMC诱导EJ细胞凋亡 ,凋亡率仅为 4.6 5 %。　结论　低剂量MMC对caspase 3的活化在诱导膀胱癌细胞凋亡中有重要作用。     

葡萄籽多酚对人乳腺癌细胞MCF-7/ADR在裸鼠体内的多药耐药逆转作用

目的　研究葡萄籽多酚 (GSP)对人乳腺癌耐阿霉素细胞MCF 7/ADR的体内多药耐药逆转作用。方法　采用人乳腺癌裸鼠移植瘤模型研究GSP对肿瘤多药耐药的体内逆转作用 ;采用流式细胞术测定不同用药P 糖蛋白 (Pgp)表达变化及肿瘤细胞凋亡率变化。 结果　体内裸鼠抑瘤实验显示GSP有一定抑瘤作用 ,抑制率为 18 35 % ,联合应用阿霉素 (ADR)可显著抑制肿瘤生长 ,2 0mg/kgGSP可有效逆转MCF 7/ADR细胞的耐药性 ,抑瘤率为 5 4 6 4 %。流式细胞术结果显示应用GSP后肿瘤细胞Pgp表达显著降低 ( 32 0 3± 2 0 9) ,与对照组 ( 5 5 13± 2 12 )相比差异有显著意义 (P <0 0 5 )。平均凋亡率为 15 12 %± 1 0 4 % ,显著高于对照组 9 0 7%± 0 4 3% (P <0 0 5 )。结论　GSP能在体内逆转MCF 7/ADR细胞的耐药性 ,其机制可能是通过抑制Pgp表达 ,并可能通过诱导肿瘤细胞凋亡来起作用     

Fas配体在膀胱肿瘤细胞系免疫逃逸中的作用

目的　探讨膀胱肿瘤细胞系的免疫逃逸机制。　方法　采用免疫细胞化学方法检测膀胱癌细胞系BIU 87中Fas配体 (FasL)的表达 ,应用BIU 87与JurkatT淋巴细胞共培养的方法体外研究FasL诱导T淋巴细胞凋亡的作用。　结果　膀胱癌细胞系BIU 87FasL表达阳性。BIU 87与JurkatT淋巴细胞共培养T细胞凋亡率为 (33.2± 6 .5 ) % ,应用抗体NOK 2中和BIU 87细胞FasL后 ,T细胞凋亡率减少为 (10 .1± 2 .7) % ,两组相比 ,差别有非常显著性意义 (P <0 .0 1)。　结论　膀胱肿瘤细胞系可能通过表达FasL主动诱导T淋巴细胞凋亡从而在膀胱肿瘤的免疫逃逸中发挥作用     

抗人IgG抗体与丝裂霉素联合应用治疗膀胱癌的实验研究

目的 探讨抗人IgG抗体和丝裂霉素(MMC)联合应用对人膀胱癌细胞株的抑制作用及机制.方法 抗人IgG抗体和MMC单独或联合作用于人膀胱癌T24细胞,噻唑盐(MTT)法检测细胞生长抑制率,流式细胞仪检测T24细胞的凋亡率,蛋白质印迹法检测半胱氨酸天冬氨酸蛋白酶3(Caspase-3)和PARP的表达.采用T24细胞裸鼠移植瘤模型进行抗人IgG抗体和MMC的体内抗瘤实验.结果 单独应用抗人IgG抗体和MMC对T24细胞生长抑制率分别为(25.02±6.71)%和(32.31±6.46)%,而二者联用的抑制率达(73.66±5.81)%.PBS、25mg/L羊IgG、25mg/L羊抗人IgG抗体、2mg/L MMC、2mg/L MMCIk 25mg/L羊IgG和2mg/L MMC加25mg/L羊抗人IgG抗体处理T24细胞72 h后细胞凋亡率分别为1.7%、2.3%、20.7%、22.4%、28.3%和53.8%.羊抗人IgG抗体、MMC、MMC加羊IgG和MMC加羊抗人IgG抗体处理T24细胞72 h后出现17 000的Caspase-3和85 000的PARP剪切片断.体内实验显示羊IgG组、羊抗人IgG抗体组、MMC组、MMC加羊抗人IgG抗体组抑瘤率分别为2.31%、12.73%,36.81%和50.51%.HE切片观察见生理盐水组和羊IgG组移植瘤细胞基本无凋亡和坏死,羊抗人IgG抗体组肿瘤细胞凋亡和坏死增多,MMC组和MMC加羊抗人IgG抗体组则见大量肿瘤细胞凋亡和坏死.结论 抗人IgG抗体和MMC联合应用对膀胱癌具有体内外双重抗瘤作用,其抗瘤机制可能与诱导肿瘤细胞凋亡有关.     

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.     

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.     

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.