血浆内脂素与多囊卵巢综合征患者糖脂代谢的相关性研究

目的探讨血浆内脂素(visfatin)水平与多囊卵巢综合征(PCOS)患者体内糖脂代谢的相关性。方法选取2016年3月至2017年10月在我院生殖科就诊的120例PCOS患者作为研究对象,按照体重指数(BMI)的不同分组:1组(62例),BMI≥25kg/m2;2组(58例),BMI介于18.5~24.9kg/m2。选择同期来我院体检中心行健康体检的女性60例为对照组(3组)。比较各组的一般资料、血浆内脂素、空腹血糖(FBG)、空腹胰岛素(FIns)等水平及稳态模型胰岛素抵抗指数(HOMAIR),并分析各项指标与内脂素的关系。结果 1组、2组的胆固醇(TC)、甘油三脂(TG)、FBG、FIns、HOMA-IR及内脂素水平均显著高于3组,高密度脂蛋白(HDL)均显著低于3组(P均0.05)。1组较2组的TG显著升高(P0.05),内脂素有升高趋势,但无显著性差异(P0.05)。血浆内脂素水平与腰围、腰臀比(WHR)、体重、BMI、FIns、HOMA-IR呈正相关;HOMA-IR、BMI是影响内脂素水平的独立因素(P0.01)。结论血浆内脂素水平与肥胖和胰岛素抵抗有关,并可能通过这一机制影响PCOS的发生发展。     

PCOS患者抗苗勒管激素水平与胰岛素抵抗及生殖激素水平的相关性研究

目的探讨多囊卵巢综合征(PCOS)患者血清抗苗勒管激素(AMH)水平与胰岛素抵抗(IR)及生殖激素水平的相关性。方法选取2017年1月至2020年2月在东莞东华医院生殖医学科就诊的PCOS患者62例,根据患者是否存在胰岛素抵抗,分为胰岛素抵抗组(HOMA-IR>2.1,PCOS-IR组,34例)和非胰岛素抵抗组(HOMA-IR<2.1,PCOS-NIR组,28例);选择同时期在同院行健康体检的30例正常女性为对照组。测定所有研究对象的血清生殖激素(AMH、FSH、LH、E2、T、PRL、P)水平,以及硫酸脱氢表雄酮(DHEA)、性激素结合球蛋白(SHBG)及空腹血糖(GLU)空腹胰岛素(FIN)水平等指标,统计分析组间各指标的差异;采用Spearman相关分析分析AMH水平与稳态模型胰岛素抵抗指数(HOMA-IR)的关系。结果3组间平均年龄、体重指数(BMI)及血清FSH、P、PRL、SHBG及DHEA水平均无统计学差异(P>0.05)。与对照组比较,PCOS组(包括PCOS-IR组和PCOS-NIR组)血清AMH、LH及T水平显著升高(P<0.05);与PCOS-NIR组比较,PCOS-IR组FIN[(20.31±12.71)mU/L vs.(5.69±1.98)mU/L]、GLU[(5.58±1.98)mmol/L vs.(4.89±1.98)mmol/L]和HOMA-IR[3.7(2.42,7.09)vs.1.28(0.84,1.63)]显著升高(P<0.05)。相关性分析结果显示,PCOS患者AMH水平与LH水平(r=0.403,P=0.001)及T水平(r=0.403,P=0.000)呈正相关,与FSH水平呈负相关(r=-0.253.P=0.044),而与年龄、BMI、E 2、P、PRL、FIN、GLU、SHBG、DHEA及HOMA-IR不存在显著相关(P>0.05)。结论PCOS患者血清AMH水平高于正常女性,其原因与高雄激素密切相关;PCOS患者血清AMH水平与胰岛素抵抗无相关性。     

肥胖多囊卵巢综合征患者血脂异常的相关危险因素分析

目的比较肥胖多囊卵巢综合征(PCOS)与肥胖非PCOS患者血脂水平及体脂分布差异,探究肥胖PCOS患者脂代谢异常的特点及影响因素。方法回顾性分析2017年12月至2018年6月就诊于盛京医院内分泌科的86例门诊患者,其中56例肥胖PCOS患者为肥胖PCOS组,30例匹配年龄、体重指数(BMI)的肥胖非PCOS患者为肥胖非PCOS组。检测身高、体重、内脏脂肪面积、血脂、性激素、甲状腺功能、hsCRP、空腹血糖及胰岛素水平,比较两组患者的代谢相关指标及激素水平,并做指标间的相关性分析。结果肥胖PCOS组血浆总胆固醇(TC)、低密度脂蛋白(LDL)、载脂蛋白B(ApoB)、LH、FSH、LH/FSH、睾酮(T)、游离雄激素指数(FAI)高于肥胖非PCOS组,血清游离甲状腺素(FT4)低于肥胖非PCOS组,均有统计学差异(P<0.05)。T、FAI、LH、FSH与TC呈正相关,T、LH与LDL呈正相关,T与ApoB呈正相关(P均<0.05)。肥胖PCOS组内脏脂肪面积、BMI与腰围之间两两呈正相关,腰围、BMI均与胰岛素抵抗指数(HOMA-IR)、超敏C反应蛋白(hsCRP)呈正相关,内脏脂肪面积与T呈正相关,甘油三酯(TG)与FAI呈正相关,HDL与hsCRP呈负相关(P均<0.05)。结论肥胖PCOS患者血脂异常程度比普通肥胖患者更严重,血清TC、LDL、ApoB水平显著升高,高雄激素可能是导致血脂差异的重要原因之一。与肥胖相关的慢性炎症状态也在一定程度上引起脂代谢紊乱,可以通过减重有效缓解肥胖PCOS患者的血脂异常。     

多囊卵巢综合征合并亚临床甲状腺功能减低患者胰岛素水平及血脂变化的研究

目的 探讨多囊卵巢综合征(PCOS)合并亚临床甲状腺功能减低(SCH)患者胰岛素水平及血脂的变化.方法 采用病例-对照的研究方法,收集2011年10月至2012年6月海军总医院生殖中心就诊的育龄期妇女,年龄在25～35周岁,选取PCOS合并SCH患者54例作为观察组,PCOS不伴有甲状腺疾病功能异常者52例作为对照组,分别测定体重、血压、静息心率、血脂,并进行糖耐量及胰岛素释放试验.采用独立样本t检验及相关分析评价PCOS合并SCH患者血脂及胰岛素变化情况. 结果 (1)PCOS合并SCH组静息心率、空腹胰岛素(FINS)高于PCOS组(P＜0.05),促甲状腺激素(TSH)、甘油三酯(TG)、餐后1h胰岛素(INS-1h)均显著高于PCOS组(P＜0.01);(2)两组中按照体重指数(BMI)比较分析:PCOS+ SCH组中BMI≥23亚组与PCOS组BMI≥23亚组相比,心率明显增快,TSH与TG显著升高,INS-1h也有明显的升高.PCOS+ SCH组中BMI＜23亚组与PCOS组BMI＜23亚组相比,除TSH有显著升高外,其余指标无显著差异;(3)相关分析显示:TSH与TG、高密度脂蛋白(HDL)、FINS、INS-1h有相关性(r分别为0.360、-0.259、0.408、0.255,P均＜0.01). 结论 PCOS合并SCH患者可能存在更严重的血脂异常及胰岛素水平的改变,TG水平的升高、HDL及胰岛素水平的改变可能成为PCOS合并SCH患者的独立危险因素.     

血清胰岛素样生长因子结合蛋白7的水平与多囊卵巢综合征及其胰岛素抵抗的关系

目的 探讨血清胰岛素样生长因子结合蛋白7(IGFBP7)水平与多囊卵巢综合征(PCOS)及其胰岛素抵抗(IR)的关系。方法 选择2021年10月至2022年12月于徐州市中心医院生殖中心就诊的PCOS患者为PCOS组(91例),收集同时期同年龄段因输卵管因素或男方因素行辅助生殖的女性为对照组(85例)。收集所有研究对象的一般资料，包括年龄、体质量指数(BMI)、腰围等；检测研究对象血清中部分生化指标如血糖、脂代谢相关指标、生殖激素水平等。采用二元Logistic回归分析评价血清IGFBP7水平与PCOS及其IR发生的关系；采用多因素线性回归分析筛查与PCOS患者IGFBP7水平升高有关的因素。结果 PCOS组患者的BMI、腰围、抗苗勒管激素(AMH)、黄体生成素(LH)、总睾酮(TT)、游离睾酮(FT)、游离雄激素指数(FAI)、空腹血糖(FPG)、空腹胰岛素(FIN)、胰岛素抵抗的稳态模型指数(HOMA-IR)、总胆固醇(CHOL)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-c)、IGFBP7水平均显著高于对照组(P<0.05),而年龄、高密度脂蛋白胆固醇(HDL-c)、性...     

PCOS患者AMH水平与内分泌代谢异常间关系的研究

目的分析多囊卵巢综合征(PCOS)患者抗苗勒管激素(AMH)水平与内分泌代谢异常之间的关系,比较高雄激素和非高雄激素型患者AMH及其它指标的差异。方法 210例PCOS患者,据AMH水平分为高AMH组(AMH≥10ng/ml,86例)和低AMH组(AMH<10ng/ml,124例);根据高雄激素临床表现或高雄激素血症分为高雄组(58例)和非高雄组(152例)。测定血清AMH、卵泡刺激素(FSH)、黄体生成素(LH)、雌二醇、睾酮(T)、空腹血糖和空腹胰岛素、总胆固醇、甘油三酯和低密度脂蛋白,计算稳态模型胰岛素抵抗指数(HOMA-IR),比较各组AMH及内分泌代谢指标差异,分析AMH水平的影响因素。结果 (1)低AMH组与高AMH组比较,BMI(24.73±5.02kg/m2 vs.23.08±4.34kg/m2)、空腹胰岛素(93.26±57.64pmol/L vs.73.81±42.62pmol/L)、HOMA-IR(3.23±2.20vs.2.51±1.64)均显著增高(P<0.05);(2)高雄组与非高雄组比较,AMH水平(11.71±5.86ng/ml vs.9.64±4.91ng/ml)、LH/FSH比值(1.94±0.93vs.1.54±0.80)、总胆固醇水平(4.94±1.38 mmol/L vs.4.36±0.83 mmol/L)、低密度脂蛋白水平(3.06±1.22 mmol/L vs.2.63±0.68mmol/L)均显著增高(P<0.05);(3)多元线性回归分析显示AMH水平与睾酮水平正相关(β=0.281,P<0.05),与BMI负相关(β=-0.264,P<0.05)。结论 PCOS患者BMI、空腹胰岛素和HOMA-IR升高导致AMH水平降低,而高雄激素型患者AMH水平和LH/FSH显著升高,并增加脂质代谢异常的风险。     

PCOS患者胰岛素抵抗与肥胖对IVF结局的影响

目的探讨PCOS患者胰岛素抵抗与肥胖对IVF结局的影响,以期为临床加强对PCOS患者胰岛素抵抗及肥胖的管理提供一定参考。方法选择2015～2017年就诊于烟台毓璜顶医院生殖医学中心接受IVF助孕治疗的第一周期鲜胚移植/冻融胚胎移植(FET)的患者590人,根据是否合并PCOS分为PCOS组(347例)和对照组(243例)。PCOS组患者又根据稳态评估-胰岛素抵抗指数(HOMA-IR)分为两个亚组:合并胰岛素抵抗(IR)的PCOS-IR组(200例),不合并IR的PCOS-NIR组(147例);按照不同的体重指数(BMI)水平分为PCOS体重正常组(115例)、PCOS超重组(132例)和PCOS肥胖组(94例)。比较各组患者的基本情况、IVF治疗相关参数及妊娠结局。结果 (1)PCOS-NIR组的抗苗勒管激素(AMH)、b-LH、b-FSH、高密度脂蛋白(HDL)水平均显著高于PCOS-IR组(P0.05)。对照组Gn总量、HCG日大卵泡数、MⅡ卵数、2PN受精卵数、优胚数均显著低于PCOS-NIR、PCOS-IR组(P0.05),临床妊娠率显著高于PCOS-IR组(P0.05);PCOS-NIR组的着床率、临床妊娠率显著高于PCOS-IR组(P0.05)。(2)按BMI分组后发现,PCOS肥胖、超重组的HOMA-IR、TG均显著高于PCOS体重正常组(P0.05);对照组的Gn天数、HCG日大卵泡数、获卵数、MⅡ卵数、2PN受精卵数、优胚数均显著低于PCOS不同BMI亚组,临床妊娠率则显著高于不同BMI亚组(P0.05);PCOS体重正常组的着床率、临床妊娠率均显著高于PCOS超重、肥胖组(P0.05)。结论 PCOS合并IR与肥胖均会对IVF结局产生不利的影响,且肥胖可加剧PCOS患者的IR程度。     

口服葡萄糖耐量试验和胰岛素释放试验在多囊卵巢综合征患者中的临床应用

目的探讨口服葡萄糖耐量试验(OGTT)和胰岛素释放试验(IRT)在筛查多囊卵巢综合征(PCOS)患者糖代谢异常中的应用情况,并分析不同糖代谢状态下的PCOS患者糖、脂代谢特点。方法纳入符合鹿特丹标准、未经治疗的PCOS患者191例,测定身高、体重、基础生殖内分泌激素、血脂水平,并行OGTT和IRT检测,计算体重指数(BMI)、胰岛素抵抗稳态指数模型(HOMA-IR)、β细胞功能指数(HOMA-β)等参数。根据血糖水平将PCOS分成糖代谢正常(NGT)组、空腹血糖受损(IFG)组、糖耐量受损(IGT)组、以及2型糖尿病(T2DM)组,筛查各组的检出情况,并比较各组糖、脂代谢的差异。结果 PCOS患者糖代谢异常的发生率24.61%(47/191),其中IFG为3.66%,IGT为18.85%,T2DM为4.19%(其中4例为IFG合并IGT,重复纳入IFG组和IGT组);随着糖代谢紊乱加重,年龄、BMI有上升的趋势(P0.05)。血胰岛素高峰值出现在2h,滞后于血糖高峰值出现的1h。随着糖代谢的恶化,各时相的血糖及胰岛素水平逐渐升高,各组血脂紊乱也逐渐加剧(P0.05)。结论 PCOS患者糖代谢异常发生率较高,利用OGTT和IRT筛查PCOS患者糖代谢异常是十分必要和重要的。     

METRNL在PCOS患者血清中的表达及意义

目的 探讨多囊卵巢综合征(PCOS)患者血清中METRNL的表达情况，寻找PCOS治疗的新靶点。方法 选取2022年7-10月就诊于河北大学附属医院生殖中心门诊被确诊为PCOS的131例患者为实验组(PCOS组),另收集同期确诊为男方因素不孕的且其他各项实验室检查结果均正常的50例女性作为正常对照组。应用酶联免疫吸附(ELISA)法检测血清中METRNL水平，化学发光法检测血清中睾酮(T)、卵泡刺激素(FSH)、黄体生成素(LH)水平；对所有研究对象进行胰岛素释放实验(IRT)及葡萄糖耐量实验(OGTT)。同时根据体质量指数(BMI)将PCOS组分为肥胖组及非肥胖组；根据胰岛素抵抗指数(HOMA-IR)将PCOS组分为胰岛抵抗组(PCOS-IR组)与非胰岛抵抗组(PCOS-非IR组),比较PCOS及PCOS亚组与对照组之间的METRNL、激素水平等差异，并用Pearson分析各指标间的相关性。结果 PCOS组与对照组比较，BMI、T、LH/FSH、 HOMA-IR及METRNL水平均有统计学差异(P<0.05)。PCOS肥胖组患者的HOMA-IR水平显著高于非肥胖者(P<0...     

青春期PCOS患者与正常女性焦虑抑郁状态差异分析

目的探讨青春期PCOS患者与同龄正常青春期女性的焦虑抑郁水平差异,探索可能的心理影响因素。方法收集2015年10月至2018年1月来我院妇科门诊就诊的76例青春期PCOS患者作为PCOS组,选择同期来我院常规体检的76例相同年龄段的正常青春期女性为对照组。比较两组患者的空腹血糖(FG)、标准化口服75g葡萄糖耐受试验的餐后2h血糖(GLU-2)、空腹胰岛素(FINS)、甘油三酯(TG)、FSH、LH、E_2和胰岛素抵抗指数(HOMA-IR)等实验室指标,及抑郁症患者健康问卷(PHQ-9)和广泛性焦虑筛查量表(GAD-7)评分情况。结果两组患者的FSH、E_2、FG、总胆固醇(TC)、高密度脂蛋白(HDL)、TG水平比较均无显著性差异(P0.05);PCOS组的总睾酮(T)、脱氢表雄酮硫酸盐(DHEA-S)、HOMA-IR、LH、GLU-2及FINS水平显著高于对照组(P0.05)。PCOS组患者的PHQ-9与GAD-7两项得分亦显著高于对照组[分别为(11.9±3.3)vs.(2.2±3.9)分和(14.9±3.7)vs.(6.5±3.9)分](P0.05)。结论青春期PCOS患者比正常青春期女性更容易出现情绪障碍,这种情绪障碍可能跟PCOS的某些临床特征有关,提示临床上对青春期PCOS患者的常规评估也应包括对情绪障碍的评估。     

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 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.     

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.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.