原发性肾病综合征患者中性粒细胞明胶酶相关脂质运载蛋白的变化及意义

目的 探讨原发性肾病综合征(PNS)患者中性粒细胞明胶酶相关脂质运载蛋白(NGAL)的变化以及与病理类型、肾小管间质损伤程度、临床指标的关系. 方法 40例PNS患者按有无急性肾小管坏死(ATN)分急性肾损伤(AKI)组及非AKI组,按病理类型分微小病变型肾病(MCD)组、系膜增生性肾小球肾炎(MsPGN)组、局灶性节段性肾小球硬化(FSGS)组、膜增生性肾小球肾炎(MPGN)组、膜性肾病(MN)组;20例健康体检者及20例因肾肿瘤做肾切除术但远离肿瘤部位的正常肾组织作正常对照.采用酶联免疫吸附试验(ELISA)法检测血清、尿液NGAL水平,免疫组织化学染色法观察肾组织NGAL表达.结果 (1) AKI组患者血、尿NGAL水平及肾组织NGAL表达显著高于非AKI组及对照组(P＜0.05).(2)MPGN组及FSGS组患者血、尿NGAL水平及肾组织NGAL表达显著高于其他病理类型组(P＜0.05).(3)在肾小管间质发展至重度病变之前,随着肾小管间质损伤程度的加重,血、尿NGAL水平及肾组织NGAL表达逐渐升高;在肾小管间质发展至重度病变时,血NGAL水平及肾组织NGAL表达下降(P＜0.05).(4)血、尿NGAL水平及肾组织NGAL表达与血肌酐呈正相关(r值分别为0.198、0.352、0.146,P值分别为0.048、0.000、0.028),与尿素氮呈正相关(r值分别为0.199、0.278、0.325,P值分别为0.043、0.000、0.019),与血白蛋白呈负相关(r值分别为-0.384、-0.318、-0.259,P值分别为0.028、0.024、0.020),与尿渗透浓度呈负相关(r值分别为-0.250、-0.256、-0.277,P值分别为0.012、0.027、0.002).结论 NGAL可作为预测PNS患者AKI的敏感指标,在一定程度下可用于评价肾小管间质病变程度及肾功能.     

儿童原发性肾病综合征中血管生成素样蛋白3的表达

目的 研究血管生成素样蛋白3 (angiopoietin-like 3 protein，ANGPTL3)在儿童原发性肾病综合征(PNS)患者肾组织中表达分布及其参与蛋白尿发生的机制。方法 ANGPTL3分别与足细胞核标记抗原(WT1)、基底膜标记抗原类肝素硫酸蛋白多糖perlecan进行双标记法免疫荧光染色。应用免疫组化的方法检测ANGPTL3和perlecan在不同病理类型的69例PNS及血尿患儿，包括微小病变(MCD)31例、膜性肾病(MN)6例、局灶节段硬化性肾小球肾炎(FSGS)6例、IgA肾病16例、薄基底膜肾病(TBMN)10例以及2例正常对照肾组织中表达，并以IMS彩色图像分析系统量化为免疫组化指数。在MCD病例中将尿蛋白肌酐比值分别与肾组织中ANGPTL3和perlecan肾小球内染色强度及电镜下平均足突宽度(FWP)进行相关分析。对不同病理诊断时间(发病至肾穿刺)分组患儿肾小球ANGPTL3和perlecan的表达进行比较。结果 (1)ANGPTL3在正常肾组织呈现微弱的沉积，而在不同病理类型的肾病综合征患儿的肾组织的肾小球和肾小管存在不同程度的表达。肾小球内ANGPTL3表达量在MCD(7.49±1.96)、MN(6.27±0.98)中显著高于正常对照(0.02±0.001)、TBMN(0.02±0.001)及FSGS(3.14±0.49)(均P < 0.05)。在IgA肾病(系膜增生型)中，蛋白尿组肾小球中ANGPTL3表达量显著高于单纯血尿组(1.90±0.81比0.03±0.01， P < 0.05)。(2) 在MCD肾组织中，WT1及perlecan荧光双标记染色显示， ANGPTL3在足细胞胞浆及沿肾小球血管袢表达。(3) ANGPTL3在肾小球表达量分别与尿蛋白肌酐比值及电镜下平均足突宽度正相关(r为0.86、0.84，P均<0.05)，并与perlecan在肾小球内表达量负相关(r为-0.83，P < 0.05)。(4)不同发病年限的MCD患儿肾组织中肾小球ANGPTL3及perlecan的表达无显著性差异。结论 在不同程度的蛋白尿及不同足突融合程度的肾组织中存在ANGPTL3的表达差异。在MCD中，ANGPTL3主要在足细胞胞浆表达，肾小球中ANGPTL3的表达与蛋白尿程度及足细胞融合程度呈正相关。     

TLR-2、ED-1和IL-1β在儿童微小病变型肾病肾组织中的表达

目的:微小病变型肾病综合征(MCNS)是儿童原发性肾病综合征(INS)最为常见的病理类型。对于MCNS的发病机制目前仍不是很清楚。本文观察Toll样受体-2(TLR-2)、单核巨噬细胞表面特异性标志抗原(ED-1)和白介素-1β(IL-1β)在儿童微小病变型肾病(MCNS)肾组织中的表达情况,探讨TLR-2、ED-1、IL-1β在MCNS发病过程中的作用。方法:遴选2013.01～2015.12间2岁～14岁新乡医学院第一附属医院临床表现原发性肾病综合征(INS)且病理确诊为MCNS病例20例,10例儿童肾肿瘤切除术后远离肾肿瘤边缘正常肾组织作为对照组。应用免疫组织化学染色GTVisionⅢ二步法,对MCNS患儿肾活检肾组织切片行TLR-2、ED-1和IL-1β免疫组织化学染色。结果:正常对照组肾小球及肾小管内TLR-2、ED-1、IL-1β无或有极微量表达。与对照组比较,MCNS组TLR-2、ED-1、IL-1β在肾小球(0.47±0.17 vs 5.15±0.21,0.55±0.14 vs 22.06±0.32,0.29±0.12 vs 17.43±0.34;P均0.05)和肾小管上皮(0.31±0.20 vs 79.45±3.65,0.84±0.39 vs 82.56±5.3,0.47±0.25 vs 63.34±4.36;P均0.01)表达均显著增高。结论:TLR-2在肾组织高表达可能诱导肾脏固有巨噬细胞释放炎症细胞因子IL-1β的过度释放,介导MCNS的局部损伤和炎症反应,促进MCNS的进展。     

汉防己甲素对肾小球硬化大鼠肾单位的影响

目的 :探讨中药汉防己甲素 (Tetrandrine)对单侧肾切除加两次注射阿霉素肾小球硬化大鼠肾单位的作用。方法 :将实验动物分为 :正常对照组、汉防己甲素治疗组、氨氯地平治疗对照组和模型组 ,于第 12周留取尿标本。肾组织病理学检查、图像分析肾单位变化 ,用Northernblot杂交检测TGF - βmRNA表达。 结果 :汉防己甲素治疗组和氨氯地平治疗对照组肾小球ECM明显减少 (肾小球ECM /GA为 0 .2 4± 0 .0 2、0 .2 9± 0 .0 1,比模型组 0 .39± 0 .0 2 ,(P <0 0 5 ) ,肾病理损伤减轻 ,肾皮质TGF - βmRNA表达下调 ,汉防己甲组和模型组肾小管上皮细胞高度无明显差异 (P <0 0 5 )。结论 :汉防己甲素治疗机理为通过下调肾皮质TGF - βmRNA表达参与了延缓肾小球硬化的机理。     

原发性肾病综合征患者IL-18的血浆水平及其在肾组织的表达

目的：初步探讨白细胞介素18(IL—18)在原发性肾病综合征(PNS)发生发展中的作用。方法：采用酶联免疫吸附(ELISA)法测定11例正常人及24例PNS患者血浆IL—18水平，同时用免疫组织化学方法检测6例正常肾组织和上述24例PNS患者肾组织IL—18的表达量。结果：PNS患者血浆IL—18水平与正常对照组IL较无统计学意义；而且各种病理类型间的差异也没有统计学意义(P均＞0．05)；而肾小球及肾小管—间质IL—18表达量却均显著高于正常对照组(P均＜0．01)。不同病理类型PNS肾小球区IL—18表达量存在差异，以膜增生性肾小球肾炎(MPGN)表达量为最高，其次为系膜增生性肾小球肾炎(MesPGN)，而膜性肾病(MD)、局灶节段性肾小球硬化(FSGS)和轻微病变(MCD)的表达量则相对较低，并且肾小球区IL—18表达量与24h尿蛋白排泄量(24h　UPQ)至正相关，与血浆白蛋白浓度(Alb)至负相关(r分别为0．669和－0．727，P均＜0．01)；肾小管—间质区IL—18表达量与小管—间质损害程度至正相关(r＝0．484，P＜0．05)。结论：肾组织IL—18高表达可能参与PNS的发病过程，而又可能以自分泌或/和旁分泌方式起作用。     

表面活性蛋白A在大鼠急性肾盂肾炎动物模型中的表达

目的探讨表面活性蛋白A(SP-A)在肾组织中的表达部位及其表达变化与肾组织感染、肾间质炎症间的关系。方法21只大鼠随机分为3组:正常对照组、假手术组和肾盂肾炎组。利用膀胱内注射菌液的方法制作肾盂肾炎模型。用HE染色评价各组肾组织炎症程度。用逆转录聚合酶链反应法(RT-PCR)检测各组SP-AmRNA表达。用Western印迹法分析各组肾组织SP-A蛋白表达。用免疫组化技术检测各组肾组织中的SP-A的表达部位和强度并分析其表达强度与炎症程度的关系。结果肾盂肾炎组肾组织炎症程度显著高于正常对照组和假手术组(54.3±11.5比6.4±1.4、8.6±1.9,P<0.05);SP-AmRNA和蛋白表达均显著增加(各组mRNA水平:2.2±0.58、0.9±0.25、1.1±0.30,蛋白水平:0.45±0.09、0.24±0.05、0.26±0.05)。正常对照组和假手术组中,SP-A的表达主要见于外髓部的肾小管上皮细胞,集合管也有一定程度的表达。肾盂肾炎模型中,SP-A在内外髓的表达均明显增加。肾脏组织炎症程度与SP-A表达强度呈正相关(r=0.67,P<0.01)。结论急性肾盂肾炎模型肾组织中的SP-A表达显著增加。感染引起的肾间质炎症越重,SP-A的表达越明显。提示SP-A可能在肾盂肾炎的天然免疫及炎症调节中发挥重要作用。     

益肾通络方对膜性肾病大鼠肾组织Nephrin、Podocin mRNA表达的影响

目的:观察益肾通络方对膜性肾病大鼠肾组织Nephrin、Podocin mRNA表达的影响,为临床治疗膜性肾病(MN)提供依据。方法:将SD大鼠随机分为正常组、模型组、贝那普利组、中药组,各组按相应剂量灌胃,于第4周末观察24 h尿蛋白定量(UTP)、血清总蛋白(TP)、血白蛋白(Alb)、三酰甘油(TG)、总胆固醇(TC)、尿素氮(BUN)、血肌酐(Scr),留取肾脏组织,用免疫荧光、光镜、电镜来观察大鼠肾组织病理变化,Real-time PCR法测Nephrin、Podocin mRNA在肾脏中的表达情况。结果:与正常组相比,其余三组TP、Alb均明显降低而TC、TG、UTP均明显升高,肾脏病理出现损害,肾组织中Nephrin、Podocin mRNA表达明显降低,差异有统计学意义(P0.05);与模型组相比,治疗组UTP、TC、TG均明显降低,TP、Alb均明显升高,肾脏病理损害较轻,肾组织Nephrin、Podocin mRNA表达有所升高(P0.05)。贝那普利组与中药组比较差异无统计学意义(P0.05)。结论:益肾通络方可明显降低膜性肾病大鼠的尿蛋白、升高血白蛋白水平、改善血脂代谢,对膜性肾病大鼠肾小球基底膜免疫复合物的沉积及基底膜的增厚有抑制作用,可减少肾脏病理损伤,能够上调膜性肾病大鼠肾组织Nephrin、Podocin mRNA的表达,延缓膜性肾病进一步发展。     

经典型蛋白激酶C在不同肾小球疾病患者肾组织的表达

目的:检测4种经典型蛋白激酶C同工酶(PKC-α、PKC-βⅠ、PKC-βⅡ和PKC-γ)在正常及不同肾小球疾病患者肾组织的表达,探讨其在肾小球疾病中的作用。方法:收集广东医科大学附属医院肾病内科行肾脏病理活检确诊的肾小球疾病患者肾组织50例,其中肾小球轻微病变、膜性肾病、局灶节段性肾小球硬化症、Ig A肾病及狼疮性肾炎各10例;收集6例来自肾肿瘤患者手术切除远离肿瘤部分、病理检查无异常的肾组织做为正常组。免疫组化法检测并分析4种经典型蛋白激酶C同工酶在正常及肾小球疾病肾组织的表达变化。结果:PKC-α、βⅠ和βⅡ在正常肾组织肾小管上皮细胞和肾小球均有表达,PKC-γ仅表达于肾小球足细胞,在肾小管间质均无表达;各经典型PKC同工酶在肾小球疾病肾组织中表达部位与正常肾组织相同,但表达量不尽相同。结论:在肾小球疾病中,PKC-α和PKC-βⅠ可能参与肾小管间质纤维化,是慢性肾脏病的潜在治疗靶点,PKC-γ可能参与足细胞生理功能的维持,不参与肾小管间质的损伤。     

不同病理类型肾病综合征患儿环孢素亲合素mRNA表达的观察

目的探讨环孢素亲合素(CyP)在儿童难治性肾病中基因表达及临床意义.方法采用逆转录聚合酶链反应(RT-PCR)测定33例难治性肾病患儿血白细胞中CyPmRNA的表达,并以正常儿童作对照.结果CyP碱基对为408bp与β-actin条带(234bp)可清晰区分.系膜增殖性肾小球肾炎(0.289±0.017)、局灶节段性肾小球硬化(0.287±0.006)患儿的血白细胞中CyPmRNA的水平高于微小病变型肾病(0.271±0.007)和膜增殖性肾小球肾炎(0.267±0.008);激素依赖、激素耐药、频繁复发患儿之间CyPmRNA表达无差异.肾病组急性期(0.281±0.016)CyPmRNA水平高于恢复期(0.267±0.100)与对照组(0.258±0.011).结论监测难治性肾病CyPmRNA的表达可能对环孢素的治疗有指导意义.     

海昆肾喜对阿霉素肾病大鼠肾组织结缔组织生长因子蛋白及其mRNA表达的影响

目的:探讨海昆肾喜对阿霉素肾病大鼠肾组织结缔组织生长因子(connective tissue growth factor,CTGF)蛋白及其mRNA的影响.方法:将54只大鼠随机分为6组,正常组、假手术组、模型组、苯那普利组和海昆肾喜小剂量组与大剂量组.采用单侧肾切除阿霉素肾病模型.术后10周处死大鼠,观察肾组织病理改变,并应用免疫组织化学方法和原位杂交法检测肾组织CTGF及其mRNA的表达.结果:正常组及假手术组肾小管上皮细胞、肾间质细胞胞浆内有少量CTGF及其mRNA阳性反应物;模型组肾小管上皮细胞、肾间质细胞内的CTGF及其mRNA在细胞浆内呈强阳性表达;海昆肾喜小剂量组、大剂量组表达较模型组显著减少(P＜0.05).结论:海昆肾喜可抑制CTGF蛋白及其mRNA的过度表达,进而减缓肾纤维化的病程进展.     

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.     

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.     

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.     

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.     

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.     

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.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.