深低温储皮后期抗原性改变的免疫学研究

以人皮和豚鼠皮新鲜及－１９６℃冷冻皮片匀浆做为抗原，研制出兔抗人和豚鼠的新鲜及－１９６℃冷冻皮片匀浆的可溶性蛋白高效价的免疫血清，并通过免疫电泳、火箭免疫电泳、免疫火箭扩散电泳及单相免疫扩散电泳等不同免疫学电泳的检测，分别对新鲜皮片及－１９６℃冷冻片抗原性改变的这一现象进行探讨与研究。结果表明：人皮、豚鼠皮其新鲜皮片的抗原成份、抗原决定簇及抗原量均显著高于相应的－１９６℃冷冻组皮片，因而证实了通过     

深低温储皮后其抗原性改变的免疫学研究

以人皮和豚鼠皮新鲜及-196℃冷冻皮片匀浆做为抗原,研制出免抗人和豚鼠的新鲜及-196℃冷冻皮片匀浆的可溶性蛋白高效价的免疫血清,并通过免疫电泳、火箭免疫电泳、免疫火箭扩散电泳及单相免疫扩散电泳等不同免疫学电泳的检测,分别对新鲜皮片及-196℃冷冻皮片抗原性改变的这一现象进行探讨与研究。结果表明:人皮、豚鼠皮其新鲜皮片的抗原成份、抗原决定簇及抗原量均显著高于相应的-196℃冷冻组皮片,因而证实了通过深低温冷冻的皮片其抗原性低于新鲜皮片的论断。     

不同冷冻温度储存皮片活力与抗原性改变的免疫学研究

以组织氧耗量与琥珀酸脱氢酶为指标，并采用火箭免疫电泳及单相免疫扩散抗原性免疫学检测方法，旨在探讨人、豚鼠新鲜皮肤与不同冷冻温度下皮肤活力及抗原性的变化。结果表明：用这两种指标百分比与平均活力百分比进行比较中，以－１９６℃速冻组平均活力％最高（７０．８％，６１％），与其它三个温度组比较有显著或非常显著意义（Ｐ＜０．０５，或０．０１）。检测皮片抗原性的结果显示：新鲜皮片匀浆抗原性（量）＞－１９６℃处理组＞－８０℃处理组＞－２０℃处理组＞４℃处理组。由此可见，经各种低温处理的皮片匀浆抗原性（量）均有不同程度的降低，且温度越高，抗原性越低，即抗原性低的组织失活就越重。     

不同冷冻温度储存皮片活力与抗原性改变的免疫学研究

以组织氧耗量与琥珀酸脱氢酶为指标，并采用火箭免疫电泳及单相免疫扩散抗原性免疫学检测方法，旨在探讨人、豚鼠新鲜皮肤与不同冷冻温度下皮肤活力及抗原性的变化。结果表明：用这两种指标百分比与平均活力分比进行比较中，以－１９６℃（速冻组平均活力％最高（７０．８％，６１％），与其它三个温度组比较有显著或非常显著意义（Ｐ＜０．０５，或０．０１）。检测皮片抗原性的结果显示：新鲜皮片均浆抗原性（量）＞－１９６℃处理     

不同冷冻温度储存皮片活力与抗原性改变的免疫学研究

以组织氧耗量与琥珀酸脱氢酶为指标,并采用火箭免疫电泳及单相免疫扩散抗原性免疫学检测方法,旨在探讨人、豚鼠新鲜皮肤与不同冷冻温度下皮肤活力及抗原性的变化。结果表明:用这两种指标百分比与平均活力百分比进行比较中,以-196℃速冻组平均活力%最高(70.8%,61%),与其它三个温度组比较有显著或非常显著意义(P<0.05,或0.01)。检测皮片抗原性的结果显示:新鲜皮片匀浆抗原性(量)>-196℃处理组>-80℃处理组>-20℃处理组>4℃处理组。由此可见,经各种低温处理的皮片匀浆抗原性(量)均有不同程度的降低,且温度越高,抗原性越低,即抗原性低的组织失活就越重。     

三种皮片匀浆上清蛋白的免疫生化分析

利用紫外吸收光谱、ＰＡＧＥ垂直板ＳＤＳ－ＰＡＧＥ及快速染色盘状ＰＡＧＥ酯酶电泳技术，对人、豚鼠的三种不同皮片的匀浆上清液蛋白成份含量及酯酶同工酶进行了比较分析，旨在为临床上应用新生皮片储皮移植提供理论依据。结果表明，豚鼠皮及人皮皮片匀浆上清液中的蛋白含量、光谱分析、ＰＡＧＥ、ＳＤＳ－ＰＡＧＥ及酯酶同工酶电泳，均是新生皮组的变化显著低于其它两组，而－１９６℃处理组与成年新鲜皮片组存在着较小差别，因此上述免疫生化学指标的判定结果为：新生皮＜（差于）－１９６℃处理成年皮＜（差于）新鲜成年皮。     

不同冷冻条件对皮肤表皮LC动态变化的影响

采用ＡＴＰａｓｅ染色法对人皮、豚鼠皮分别进行常温新鲜皮片组及Ｈ抗冻液组郎格罕氏细胞（ＬＣ）计数的比较，并对４种（４℃，－２０℃，－８０℃，－１９６℃）不同温度处理组的６个（１，２，３，５，７，１４天）时相点的ＬＣ进行了动态观察。结果表明，人皮及豚鼠皮常温新鲜皮片组与Ｈ抗冻液皮片组的ＬＣ计数，在数量与形态学方面比较差异均无显著意义（Ｐ＞０．０５）。不同温度处理组及其各时相点ＬＣ计数规律为：冷冻温度越低，各实验组相同时相点的ＬＣ均值下降越显著，ＬＣ下降速率的谷值，以－１９６℃组下降最快（１天），该冷冻组降低的幅度也最大（仅为正常值的４０％～５０％）。在细胞形态学观察中发现冷冻后ＬＣ均存在明显变形、胞体缩小、胞突变短、消失等结构的改变。皮肤表皮ＬＣ是重要的移植抗原，它的数量的减少及细胞形态改变可能将会对推迟异体皮片的排斥反应及延长皮片移植后存活时间起到重要作用。     

不同冷冻温度储存后皮片匀浆上清蛋白的生化分析

人（尸体皮），豚鼠及小鼠皮片经４℃、－２０℃、－８０℃、－１９６℃储存后，应用紫外分光光度计及聚丙烯胺凝胶电泳技术，对其匀浆上清液中的蛋白质成份含量，进行了紫外光吸收能力及酯酶同工酶分析。结果显示：皮片经不同温度储存后其匀浆上清中的蛋白质成份及含量与新鲜皮相比，有不同程度的变化。     

三种皮片匀浆上清蛋白的免疫生化分析

利用紫外吸收光谱、ＰＡＧＥ垂直板ＳＤＳ－ＰＡＧＥ及快速染色盘状ＰＡＧＥ酯酶电泳技术，对人、豚鼠的三种不同皮片的匀浆上清液蛋白成份含量及酯酶同工酶进行了比较分析，旨在为临床上应用新生皮片储皮移植提供理论依据。结果表明，豚鼠皮及人皮皮片匀浆上清液中的蛋白含量、光谱分析、ＰＡＧＥ、ＳＤＳ－ＰＡＧＥ及酯酶同工酶电泳，均是新生皮组的变化显著低于其它两组，而－１９６℃处理组与成年新鲜皮片组存在着较小差别，因此     

不同冷冻温度储存后皮片匀浆上清蛋白的生化分析

人（尸体皮），豚鼠及小鼠皮片经４℃、－２０℃、－８０℃、－１９６℃储存后，应用紫外分光光度计及聚丙烯胺凝胶电泳技术，对其匀浆上清液中蛋白质成分含量，进行了紫外光吸收能力及酯酶同工酶分析。结果显示：皮片经不同温度储存后其奖浆上清中的蛋白质成份及含量与新鲜皮相比，有不同程度的变化。     

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.     

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.     

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.