间断性和持续性肝缺血再灌注对线粒体功能的影响

间断性和持续性肝缺血再灌注对线粒体功能的影响孙经建张柏和吴孟超陈汉钱光相作者采用大鼠肝缺血再灌注损伤模型，观察肝线粒体功能，以及肝组织内钙离子、脂质过氧化物（ＬＰＯ）和超氧化物歧化酶（ＳＯＤ）含量的变化，旨在比较间断性与持续性肝血流阻断对上述指标的影...     

热休克蛋白70在肝血流间断阻断再灌注后的表达及作用

目的：探讨热休克蛋白70（HSP70）在肝血流间断和持续阻断再灌注后的表达及作用。方法：将实验大鼠分为持续阻断组，间断阻断组和假处理组，用免疫金银法观察再灌注1h后肝组织中HSP70的表达，并检测肝细胞及线粒体功能。结果：HSP70面肝持续性缺血再灌注后无表达，肝细胞和线粒体功能均显著下降，间断性血流阻断组则有HSP70的合成表达，该组与假处理组的肝细胞和线粒体功能指标的差异均无显著性。结论：HSP70在间断性肝血流阻断再灌注后的早期合成，有利于保护肝细胞和线粒体功能。     

胆道梗阻大鼠肝切除术后残肝细胞能量代谢状况的研究

目的 探讨胆道梗阻大鼠肝切除术后残肝细胞能量代谢状况。方法 实验大鼠分实验组（３０只）、对照组（２０只）２组。对正常大鼠和胆道梗阻５ｄ大鼠行７０％肝切除和胆肠引流术、观察术后２４ｈ残肝细胞线粒体呼吸功能（线粒体ＲＳ３、ＰＣＲ和ＡＤＰ／Ｏ比值）和ＡＴＰ量改变。结果 正常大鼠肝切除后肝细胞线粒体功能代偿性增加。胆道梗阻大鼠肝切除术后肝线粒体代偿能力减弱（Ｐ〈０．０５）,肝细胞能量代谢障碍（Ｐ〈０．０１     

联合应用超氧化物歧化酶,阿魏酸钠抗肝缺血再灌注损伤

目的研究联合应用外源性超氧化物歧化酶（ＳＯＤ）与阿魏酸钠（ＳＦ）对肝缺血再灌损伤的保护作用。方法将３２只成年雄性ＳＤ大鼠随机分为对照组、ＳＦ保护组、ＳＯＤ保护组和ＳＦ与ＳＯＤ联合保护组。通过阻断大鼠肝门１ｈ后再开放建立肝缺血再灌注损伤模型,在肝缺血前及肝再灌注２ｈ时测肝组织丙二醛（ＭＤＡ）,ＳＯＤ和测血谷丙转氨酶（ＡＬＴ）,谷草转氨酶（ＡＳＴ）。并取肝组织作光镜及电镜观察。结果再灌注２ｈ时ＳＦ保护组与ＳＯＤ保护组的肝组织ＭＤＡ生成,ＳＯＤ消耗,血清ＡＬＴ,ＡＳＴ升高值均高于ＳＦ与ＳＯＤ联合保护组（Ｐ＜０．０１或Ｐ＜０．０５）,且ＳＦ和ＳＯＤ联合保护组的肝细胞显微、超微结构损害的改变较ＳＯＤ或ＳＦ保护组轻。结论ＳＦ与ＳＯＤ联合保护组清除氧自由基（ＯＦＲ）的作用强于ＳＯＤ或ＳＦ保护组,对鼠肝缺血再灌注所致肝细胞的结构和功能损伤的保护作用比单独使用ＳＯＤ或ＳＦ强。     

影响肝缺血再灌注损伤主导因素的肌理

我们动态观察ＳＤ大鼠肝缺血４５．６０分钟复流０．１０，６０，１２０分钟，人体肝门阻断１５分钟复流５－１０分钟，４０分钟不同时限肝细胞内游离钙浓度，肝组织脂质过氧化自由基电子自旋共振信号最大幅值及脏脏超微结构病理变化，结果发现，在再灌注早期（大鼠肝血４５分钟复流１０分钟，人体肝缺血１５分钟复流５－１０分钟已可观察到（「Ｃａ＾２＋）」ｉ）增高现象，而ＲＯＯ．Ｙｍａｘ变化不显著，肝细胞超微结构仅表现为线     

参麦注射液抗肝缺血再灌注损伤的研究

目的：研究参麦注射液对肝缺血再灌注损伤的保护作用。方法：将３７只成年雄性ＳＤ大鼠随机分成假手术对照组（ＳＯＣ）、缺血再灌注组（Ｉ／Ｒ）、缺血再灌注加参麦组（Ｉ／Ｒ＋ｓｈｅｎｍａｉ）。通过阻断大鼠肝门３０ｍｉｎ后再开放建立肝缺血再灌注损伤模型,在肝脏再灌注９０ｍｉｎ时测肝组织丙二醛（ＭＤＡ）、超氧化物歧化酶（ＳＯＤ）和测血ＡＬＴ、ＡＳＴ、ＬＤＨ,并取肝组织作光镜及电镜观察。结果：再灌注９０ｍｉｎ时Ｉ／Ｒ＋Ｓｈｅｎｍａｉ组的肝组织ＭＤＡ生成,ＳＯＤ消耗,血清ＡＬＴ、ＡＳＴ、ＬＤＨ升高值均少于Ｉ／Ｒ组（Ｐ＜０．０１）,且Ｉ／Ｒ＋Ｓｈｅｎｍａｉ组的肝细胞显微、超微结构损害的改变较Ｉ／Ｒ组轻。结论：参麦注射液能清除肝缺血再灌注过程中产生的氧自由基,对鼠肝缺血再灌注所致肝细胞的结构和功能损伤有保护作用     

硫酸镁对实验性颅脑损伤后线粒体酶活性的影响

探讨硫酸镁对大鼠颅脑损伤后脑线粒体ＡＴＰ酶、超氧化物歧化酶（ＳＯＤ）的活性及线粒体Ｃａ２＋、Ｍｇ２＋及ＭＤＡ含量的影响。方法对自由落体致颅脑损伤的ＳＤ大鼠在致伤同时腹腔注射硫酸镁治疗,伤后２４小时测定线粒体Ｎａ＋－Ｋ＋ＡＴＰ酶、Ｃａ２＋－ＡＴＰ酶、Ｍｇ２＋－ＡＴＰ酶、ＳＯＤ的活性及线粒体Ｃａ２＋、Ｍｇ２＋及ＭＤＡ含量。结果颅脑损伤后大鼠脑线粒体Ｎａ２＋－Ｋ＋ＡＴＰ酶,Ｃａ２＋－ＡＴＰ酶,Ｍｇ２＋－ＡＴＰ酶的活性均明显下降（Ｐ＜０．０５）,线粒体Ｃａ２＋、ＭＤＡ含量增加,Ｍｇ２＋含量及ＳＯＤ活性明显降低（Ｐ＜０．０５）。与创伤组相比,硫酸镁治疗组上述指标均有明显改善（Ｐ＜０．０５）。结论硫酸镁可以改善损伤后脑线粒体酶活性并减轻线粒体钙超载。     

热休克蛋白70对肝缺血再灌注损伤的作用及机制探讨

目的 探讨热休克蛋白70（Heat shock protein 70,HSP70）对大鼠肝缺血再灌注损伤的作用及机制。方法 实验大鼠分为持续阻断组、间断阻断组和假处理组。用免疫金银法观察再灌注1h后肝组织HSP70蛋白的表达,并检测其肝细胞及线粒体功能、肝组织内钙和脂质过氧化物（Lipid peroxide,LPO）含量,以及超氧化物歧化酶（Superoxide dismuase,SOD）活性。结果 HSP70蛋白在持续性缺血再灌注后无表达,肝细胞功能、线粒体功能和SOD活性均显著下降,而肝组织内钙和LPO值均显著升高。间断性血流阻断组则有HSP70蛋白的合成表达,该组与假处理组的上述各项指标的差异均无显著意义。结论HSP70蛋白在肝缺血再灌注后的诱导产生有利于保护肝细胞及线粒体的功能,该效应与细胞内钙稳定和SOD活性增高有关。     

热休克蛋白70对肝缺血再灌注损伤的作用及机制探讨

目的 探索热休克蛋白70（Heat shock protein 70,HSP700）对大鼠肝缺血再灌注损伤的作用及机制。方法 实验大鼠分为持续阻断组，间断阻断组和假处理组。用免疫金银法观察再灌注1h后肝组织HSP70蛋白的表达，并检测其肝细胞及线粒体功能，肝组织内钙和脂质过氧化物（Lipid peroxide,LPO)含量，以及超氧化物歧化酶（Superoxide dismutase,SOD)活性。结果 HSP70蛋白在持续性缺血再灌注后无表达，肝细胞功能，线粒体功能和SOD活性均显下降，而肝组织内钙和LPO值均显升高。间断性血流阻断组则有HSP70蛋白的合成表达，该组与假处理组的上述各项指标的差异均无显意义。结论 HSP70蛋白在肝缺血再灌注后的诱导产生有利于保护肝细胞有线粒体的功能，该效应与细胞内钙稳定和SOD活性增高有关。     

胆道梗阻后肝细胞线粒体钙含量变化和肝脂质过氧化损害的实验研究

为了解胆道梗阻对肝脏的损害机理,在复制大鼠胆道梗阻模型基础上,分离肝细胞线粒体,动态检测肝细胞线粒体钙含量,肝组织ＭＤＡ、ＳＯＤ含量,血清ＴＢｉｌ、ＡＬＴ、ＡＬＰ及ＧＧＴ含量。结果：肝细胞线粒体钙含量、肝组织ＭＤＡ含量和血清ＴＢｉｌ、ＡＬＴ、ＡＬＰ及ＧＧＴ水平均随梗阻时间延长而逐渐升高（Ｐ＜０．０５）,肝组织ＳＯＤ含量则逐渐减少（Ｐ＜０．０５）;肝细胞线粒体钙含量与肝组织ＭＤＡ含量、血清ＡＬＴ及ＡＬＰ含量变化呈明显正相关,ｒ分别为０．９６７、０．９２４和０．９１９（Ｐ＜０．０１）;肝组织ＭＤＡ含量与血清ＡＬＴ和ＡＬＰ含量变化呈明显正相关,ｒ分别为０．９４９和０．８４３（Ｐ＜０．０１）。结论：肝细胞线粒体钙超载和脂质过氧化损伤密切相关,在胆道梗阻所致肝损害过程中起重要作用。     

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.     

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.     

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.