大黄酸对转化生长因子β1诱导的人肾小管上皮细胞血小板反应蛋白1表达的影响

目的探讨大黄酸对转化生长因子β1（transforming growth factor β1,TGF-β1）诱导的人肾小管上皮细胞（HK-2）血小板反应蛋白1（thrombospondin-1,TSP1）表达的影响。方法体外培养细胞,观察TGF-β1（4ng／ml）诱导下低、中、高浓度的大黄酸（10μg／ml、20μg／ml和40μg／ml）对HK-2细胞TSP1 mRNA和蛋白表达的影响。Real Time PCR检测TSP1 mRNA表达,Western Blot检测TSPI蛋白表达。结果与空白对照组比较,TGF-β1（4ng／ml）明显上调HK-2细胞TSP1 mRNA和蛋白表达。与TGF-β1（4ng／ml）阳性对照组比较,中浓度和高浓度大黄酸明显抑制了TSP1 mRNA和蛋白表达。结论大黄酸能抑制TGF-β1诱导的HK-2TSP1 mRNA和蛋白表达。     

黄芪对人肾小管上皮细胞细胞外基质分泌的影响及其机制探讨

目的：探讨黄芪对人肾小管上皮细胞细胞外基质分泌的影响及甚可能机制。方法：将体外培养的人肾小管上皮（HK-2）细胞株转板至细胞融合并同步后,分为空白对照组、转化生长因子-β（TGF-β1）刺激组（5ng／ml）、TGF-β1加黄芪100μg／ml组、TGF-β1加黄芪1mg／ml组。作用24h后半定量逆转录多聚酶链反应（RT—PCR）检测纤维连接蛋白（FN）及纤溶酶原激活物抑制剂-1（PAI-1）mRNA;酶联免疫吸附试验（ELISA）法检测上清液中FN的含量;westernblot检测PAI-1的表达。结果：（1）HK-2细胞表达少量FN和PAI-1;（2）HK-2细胞在5ng／ml TGF-β1．刺激下分泌FN、PAI—1mRNA及FN、PAI-1蛋白表达明显增加,与空白对照组比较差异有统计学意义（P〈0．01）;（3）HK-2细胞在TGF-β1和不同浓度的黄芪作用后,可使FN、PAI-1mRNA及蛋白表达减少,与TGF-β1组比较差异有统计学意义（P〈0．01）,尤以黄芪1mg／mi组为甚。结论：TGF—β1可促进HK-2细胞分泌FN和PAI—1,黄芪可部分拮抗TGF-β1的上述效应。这可能是黄芪预防或改善肾小管间质病变的作用机制之一。     

HB-EGF对系膜细胞增殖及转化生长因子-β1表达的影响

目的：观察肝素结合性表皮生长因子样生长因子（HB-EGF）对肾小球系膜细胞（GMC）增殖及转化生长因子-β1（TGF-β1）表达的作用。方法：以原代培养大鼠肾小球系膜细胞为细胞模型,采用MTT、ELISA、RT-PCR等方法观察外源性HB-EGF对系膜细胞增殖及TGF-β1表达的影响。结果：（1）不同浓度HB-EGF对系膜细胞增殖有不同影响,10ng/ml时无刺激GMC增殖作用（P〉0.05）,100、1000ng/ml均能刺激GMC增殖（P〈0.01）,100ng/ml作用最明显。（2）HB-EGF（10ng/ml、100ng/ml、1000ng/ml）能刺激系膜细胞TGF-β1的表达（P〈0.01）,100ng/ml时作用最强。（3）100ng/mlHB-EGF刺激GMC24h、36h、48h,系膜细胞TGF-β1的表达均增加,随作用时间而变化,刺激36h和48h比24h作用更明显（P〈0.05）。结论：一定浓度范围内HB-EGF刺激GMC增殖,促进系膜细胞TGF-β1的表达,且具有一定的时间及浓度依赖性。     

β1转化生长因子浓度对体外诱导骨髓间充质细胞构建软骨的影响

目的 探讨β1转化生长因子（TGF-β1）浓度对体外诱导猪骨髓间充质细胞（BMSCs）构建组织工程化软骨的影响，明确TGF-β1诱导剂量对细胞分化的作用，为体外软骨构建提供适宜的诱导因子应用浓度参数。方法 抽取8周龄猪髂嵴骨髓，应用贴壁法分选单个核细胞，体外培养扩增后获得BMSCs，收集第2代细胞，以5×10^7个／cm。细胞的密度接种到聚羟基乙酸（PGA）制成的圆柱形三维支架材料上（直径5mm，厚度2mm），7d后应用不同浓度TGFβ1（A组：5ng／ml、B组：10ng／ml、C组：20ng／ml、D组：50ng／m1）与IGF-1（50ng／m1）及地塞米松（40ng／m1）组成诱导剂，分别进行体外诱导培养。8周后取材行大体观察，体积、湿重及聚合蛋白多糖（GAG）定量，组织学及Ⅱ型胶原免疫组织化学等检测。结果 B、C、D组形成细胞材料复合物组织学结构较为类似，有明显的软骨陷窝，分布有大量Ⅱ型胶原及GAG；A组软骨陷窝结构较少，胞外基质染色较浅。B、C、D组的组织湿重、体积和GAG含量均明显高于A组。结论 诱导三维支架上的BMSCs体外构建组织工程化软骨过程中，10ng／ml的TGF-β1诱导浓度具有良好的促分化效能，TGF-1的促分化作用并未表现出明显的剂量依赖性。     

转化生长因子β1诱导肾间质成纤维细胞表型转化及其对结缔组织生长因子基因表达的影响

目的 研究转化生长因子β1（transforming growth factor beta-1,TGF-β1）诱导大鼠正常肾间质成纤维细胞（NRK-49F）表型转化过程中结缔组织生长因子（connective tissue growth factor,CTGF）基因表达的变化.方法 以不同浓度的TGF-β1（0、0.5、1、2、5、10 ng/ml）刺激NRK-49F细胞,分别应用MTT比色法、Western Blot、Northern Blot方法,检测TGF-β1刺激后肾间质成纤维细胞的增殖、Ⅰ型、Ⅲ型前胶原mRAN的表达、细胞表型标志物α-SMA mRNA及蛋白质表达、CTGFmRNA的表达变化.结果 1 ng/ml浓度以上TGF-β1能显著促进NRK-49F细胞增殖,上调Ⅰ、Ⅲ型前胶原mRNA的表达水平,诱导肌成纤维细胞表型标志α-SMA mRNA及蛋白质的表达,显著上调CTGF mRNA的表达水平（P＜0.01或P＜0.05）;以上效应均呈浓度依赖性.同时CTGF mRNA表达水平的增高与细胞表型转化的程度相一致.结论 TGF β1能诱导肾间质成纤维细胞发生表型转化,并促进了细胞增殖及细胞外基质的合成;该效应与TGF β1显著上调CTGF的基因表达一致.     

转化生长因子β1对大鼠原代肾小球系膜细胞血管内皮生长因子表达的影响

目的：探讨原代培养的大鼠肾小球系膜细胞血管内皮生长因子（vascular endothelial growth factor，VEGF）的表达及转化生长因子-β1（transforming growth factor-β1，TGF-β1）对其表达的影响。方法：采用RT-PCR和Westernblot方法检测大鼠原代培养的肾小球系膜细胞VEGF表达及不同浓度、不同时间的TGF-β1刺激对VEGF表达的作用。结果：原代培养的大鼠肾小球系膜细胞表达VEGF164、120mRNA，TGF-β1呈时间依赖性增加其表达，在12h表达最高，分别为刺激前3．17、2．925倍，有统计学差异（P〈0．001）。在剂量反应曲线上，2ng／ml TGF-β1刺激作用最强，VEGF164、120mRNA表达分别为未刺激组的2．82、2．45倍，有统计学差异（P〈0．001）。与VEGF mRNA表达一致，大鼠原代肾小球系膜细胞仅见VEGF164蛋白表达，2ng／ml TGF-β1呈时间依赖性的增加VEGF 164蛋白表达，24h达高峰，为刺激前的2．37倍。结论：促进肾小球系膜细胞VEGF表达可能是TGF-β1介导肾脏损害发生、发展的机制之一。     

转化生长因子-β、碱性成纤维生长因子和血小板衍生生长因子在大鼠骨折愈合中的表达

目的观察转化生长因子-β（transforminggrowthfactor-β,TGF-β）、碱性成纤维生长因子（basicfi—broblastgrowthfactor,bFGF）和血小板衍生生长因子（platelet—derivedgrowthfactor,PDGF）在大鼠骨折愈合中的表达和分布情况。方法选用SD大鼠制作胫骨骨折模型,伤后不同时期处死取材,分别进行组织学和TGF-β、bFGF和PDGF的免疫组化染色观察。结果（1）伤后3d开始形成原始骨痂。I周时肉芽组织中的间质细胞开始分化为软骨细胞,软骨形成后再进行软骨内化骨。4周时形成连接骨折端的桥接骨痂。（2）伤后早期血肿中炎性细胞表达bF-GF和PDGF。伤后1周骨膜增殖细胞、肉芽组织中的成纤维细胞、内皮细胞、骨端骨细胞以及原始骨痂成骨细胞表达TGF-β、bFGF和PDGF。伤后2周软骨细胞表达TGF-β、bFGF和PDGF。结论TGF-β、bFGF和PDGF有各自的表达和分布特点,并共同调解骨原细胞的增殖和成骨细胞、软骨细胞的分化,最终完成骨折愈合。     

TGF-β1对UVA照射皮肤成纤维细胞Ⅰ型，Ⅲ型胶原合成和表达的影响

目的：探讨转化生长因子-β1（tansforming gowth factor—beta 1,TGF—β1）对长波紫外线（ultraviolet A,UVA）照射皮肤成纤维细胞Ⅰ型、Ⅲ型胶原合成和表达的影响。方法：通过MTT法检测TGF-β1干预后成纤维细胞增殖活性,选择UVA照射剂量为15J／cm^2,联免疫法（ELISA）测定不同剂量即TGF—β1小剂量组（UVA＋TGF—β1 0．1ng／ml）、中剂量组（UVA＋TGF—β1 1ng／ml）、大剂量组（UVA＋TGF—β1 10ng／ml）处理后成纤维细胞清夜中Ⅰ型、Ⅲ型胶原含量,半定量RT—PCR检测成纤维细胞Ⅰ型、Ⅲ型胶原mRNA表达。结果：UVA照射体外培养的皮肤成纤维细胞,导致成纤维细胞增殖活性下降,给予不同剂量TGF-β1干预后,成纤维细胞增殖活性与UVA照射组比较,明显提高;成纤维细胞上清液中Ⅰ型、Ⅲ型胶原含量增加,成纤维细胞内Ⅰ型、Ⅲ型胶原mRNA表达增强。结论：TGF-β1可提高UVA照射体外培养成纤维细胞增殖活性;增加UVA照射体外培养的皮肤成纤维细胞Ⅰ型、Ⅲ型胶原含量,增强成纤维细胞Ⅰ型、Ⅲ型胶原mRNA表达,对皮肤成纤维细胞起保护作用。     

转化生长因子-β1和胰岛素样生长因子-1对人髓核细胞体外增殖活性的影响

目的：研究转化生长因子-β1（TGF—β1）和胰岛素样生长因子-1（IGF—1）单独及联合应用对人髓核细胞体外增殖活性的影响，并观察其量效和时效关系。方法：体外分离培养人髓核细胞．将传2代细胞种于96孔板，采用噻唑蓝（MTT）比色法，观察TGF—β1和IGF—1在1％和10％血清浓度下对人髓核细胞体外增殖的调节作用及其剂量、时间与作用效果的关系。结果：在1％血清条件下，IGF—1的作用不显著，TGF—B1具有促增殖作用。在10％血清条件下，TGF—B1和IGF—1均能提高细胞的增殖活性，并且在有效浓度范围内呈剂量效应关系，TGF—B1的作用强于IGF—1。二者联合应用效果更显著。结论：TGF—B1和IGF—1均能不同程度地促进入髓核细胞的体外增殖，其效应在一定范围内与剂量和时间呈正相关．联合应用促进增殖作用更显著。     

碱性成纤维细胞生长因子和表皮生长因子对骨骼肌源性干细胞的促增殖效应

目的观察碱性成纤维细胞生长因子（basic fibroblast growth factor，bFGF）和表皮生长因子（epidermal growth factor，EGF）单独及联合应用对骨骼肌源性干细胞（muscle derived stem cells，MDSCs）生长的影响。方法取出生24h内的昆明小鼠15只，采用连续预贴壁法从小鼠后肢肌分离培养MDSCs，用含2％胎牛血清的DMEM培养基促进其向骨骼肌细胞分化。取原代MDSCs及MDSCs分化细胞，采用免疫细胞化学染色检测干细胞标志Sca-1和骨骼肌细胞标志α-Sarcomeric肌动蛋白的表达。HE染色观察细胞肌管形成。MTT比色法检测不同浓度（6．25、12．50、25．00、50．00、100．00ng／ml）的bFGF和EGF单独应用96h对MDSCs增殖的影响以及二者（100．00ng／ml）联合作用24、48、72和96h对MDSCs增殖的影响。结果从新生小鼠后肢肌成功分离培养MDSCs，免疫细胞化学染色90％以上的MDSCs呈Sca-1阳性，分化形成的肌管呈α—Sarcomeric肌动蛋白阳性。HE染色可见肌管形成。bFGF、EGF对MDSCs的促增殖效应随浓度的增加而增加。与阴性对照组比较，bFGF于12．50ng／ml出现促增殖效应（P〈0．05）；25．00ng／ml组与12．50ng／ml组比较，作用提高（P〈0．01）；50．00、100．00ng／ml组较25．00ng／ml组无明显提升（P〉0．05）；EGF的作用与bFGF类似，但于50．00ng／ml时趋于饱和。与阴性对照组比较，EGF于72h、bFGF于96h表现促增殖效应（P〈0．01），而二者联合应用于24h即表现促增殖效应（P〈0．01），并于48、72和96h增殖效应均较单独应用显著提高（P〈0．05）。结论bFGF和EGF都能促进MDSCs的增殖，联合作用更快、更强。     

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.