改良超滤与零平衡超滤结合应用于婴幼儿体外循环手术59例的体会

目的总结改良超滤与零平衡超滤在59例婴幼儿体外循环手术中结合应用的经验、方法及临床效果。方法 59例婴幼儿,其中男40例,女19例,年龄4月～3岁之间,体重5～14kg,体外循环手术中均采用在体外循环过程中根据灌注压、红细胞压积给予零平衡超滤,停机后给予改良超滤。结果 59例患儿均顺利停机,无1例死亡,未出现超滤并发症,转中血球压积18～30(22.5±2)%,停机改良超滤后血球压积上升至32～38(35.8±1.4)%,在CCU住院时间为2～6d,皆顺利出院。结论在婴幼儿体外循环中将零平衡超滤与改良超滤的结合应用,零平衡超滤利于炎性介质的滤出,改良超滤可在CPB结束后快速排出多余的水分,提高红细胞压积,改善心肺功能,适用于低体重血液稀释度大的婴幼儿及体外循环时间长者。     

Serotonin glucuronidation by Ah receptor- and oxidative stress-inducible human UDP-glucuronosyltransferase (UGT) 1A6 in Caco-2 cells

Caco-2 cells are a widely used model in drug development to study intestinal drug transport and metabolism. Recently, serotonin (5-hydroxytryptamine, 5-HT) has been characterized as a highly selective substrate of human UDP-glucuronosyltransferase UGT1A6 [Krishnaswamy S, Duan SX, von Moltke LL, Greenblatt DJ, Court MH. Validation of serotonin (5-hydroxytryptamine) as an in vitro substrate probe for human UDP-glucuronosyltransferase (UGT) 1A6. Drug Metab Disp 2003; 31:133-9], an isoform which conjugates planar phenols and is inducible by Ah receptor agonists and by oxidative/electrophile stress. To gain more insight into intestinal 5-HT disposition, uptake and metabolism of this neurotransmitter was studied in Caco-2 cell monolayers. It was found that 5-HT was taken up from the basolateral and to a lesser extent from the apical surface. It was mainly excreted basolaterally as 5-HT glucuronide. 5-HT UGT activity and UGT1A6 mRNA were induced by Ah receptor agonists and by oxidative stress generated by tert-butylhydroquinone and by isomeric thymoquinone, a potential antitumor agent and constituent of Nigella sativa seeds, commonly used as a condiment in the Middle East. While UGT1A6 induction was clearly detectable in NAD(P)H:quinone oxidoreductase 1 (NQO1)-deficient Caco-2 cells, it was not induced in NQO1-efficient HT-29 colon adenocarcinoma cells. The results suggest that--in addition to its detoxification function--intestinal UGT1A6 contributes to intestinal homeostasis of 5-HT from dietary sources and from release by enterochromaffin cells.     

MUF对偏头痛诊断价值的研究

为了研究偏头痛样超声频谱（MUJ）对偏头痛的诊断价值,使用TCD对537例偏头痛患者和230例正常人进行检测,发现偏头痛组的MUF明显高于对照组（P＜0．001）,且MUF的发生与发作频度、病程有关（P＜0．01－0．001）,与是否有先兆无关（P＞0．05）。提示MUF在偏头痛患者有一定普遍性,可作为偏头痛诊断的一个有用指标。     

Characterization of enzyme activities of Cytochrome P450 enzymes, Flavin-dependent monooxygenases, N-acetyltransferases and UDP-glucuronyltransferases in human reconstructed epidermis and full-thickness skin models

With the perspective to use human reconstructed skin models for genotoxicity testing which require metabolic activation of xenobiotics, this study aimed to characterize activities of biotransforming enzymes within two human reconstructed skin models, the epidermis model EpiDerm™ (MatTek) and the Phenion® Full-Thickness skin model Phenion®FT (Henkel). According to existing gene expression profiles, Cytochrome P450 (CYP) enzymes, Flavin-dependent monooxygenases (FMO), N-acetyltransferases (NAT) and UDP-glucuronyltransferases (UDP-GT) were investigated in S9 or microsomal fractions. CYP-catalyzed monooxygenation was assayed using 7-ethoxyresorufin, pentoxyresorufin and benzyloxyresorufin as substrates. FMO activity was tested using benzydamine. Conjugating activities of NAT and UDP-GT were determined by acetylation of p-aminobenzoic acid or glucuronation of 4-methylumbelliferone, respectively. Although CYPs were detected by expression profiling, no CYP activity was detected in either the epidermal nor the full-thickness reconstructed skin model while expression and activity of FMO, UDP-GT and NAT were demonstrated in both.     

Mechanically assisted bidirectional cavopulmonary shunt in neonates and infants: An acute human pilot study

Objective

Poor survival following surgical palliation for hypoplastic left heart syndrome (HLHS) raises the question of the need for a paradigm shift. This is the first human study to investigate the possibility of primary “in-series” palliation in neonates and infants with HLHS in an acute setting with the aid of 2 types of mechanical assist: superior vena cava (SVC)–to–pulmonary artery (PA) pump assist and SVC–to–right atrium (RA) oxygenation assist.

改良超滤对成人重症心脏瓣膜置换术的影响

目的探讨改良超滤技术(MUF)在成人重症心脏瓣膜置换术中的影响。方法 50例重症心脏瓣膜病患者随机分为实验组(MUF组,n=25)和对照组(CUF组,n=25),在术中分别采用改良超滤和常规超滤(CUF),对两组术后早期临床资料进行对比研究。结果两组间的红细胞比容(Hct)在术前、超滤前差异无统计学意义(P>0.05),在超滤后MUF组高于CUF组(P<0.01),MUF组术后出血及库血使用均低于CUF组(P<0.05),术后血流动力学较平稳,呼吸机支持时间较短,术后24 h尿量明显减少。但术后ICU滞留时间、病人下床活动时间以及术后出院时间差异无统计学意义(P>0.05)。结论改良超滤可在手术后短时间内浓缩血液,提高Hct,改善肺功能,减少出血和库血使用,但不能改善患者远期预后。     

改良超滤对犬体外循环肺功能的影响

目的 通过观察改良超滤对犬体外循环肺功能的影响,探讨应用超滤对肺的保护作用.方法 选择18只健康成年犬随机分成对照组、CPB组和改良超滤组三组.三组动物均腹腔内注射戊巴比妥,麻醉生效后,仰卧位固定,气管插管,监测心电图、舌粘膜氧饱和度(SpO2)等,行右侧股动、静脉置管分别测平均动脉压(MAP)及中心静脉压(CVP).开胸时接麻醉工作站行机械通气,三组分别在开胸未行机械通气前、停机时、停机60 min采集动脉血行血气分析,计算犬RI和OI;取肺组织行HE染色观察病理学变化.结果 (1)肺组织病理学变化:对照组犬肺组织未见明显的病理变化,CPB后肺组织见大量的炎性细胞浸润,肺泡间隔增宽,甚至肺泡腔内有水肿波;改良超滤组肺组织改变明显轻于CPB组.(2)RI和OI的变化:开胸未行机械通气前三组犬RI和OI比较差异无统计学意义(P＞0.05).组内比较:A组各时间点RI、OI差异无统计学意义;B组、C组T2、T3时点的RI明显高于T1,而OI相反,差异有统计学意义(P＜0.05).组间比较:与对照组比较,CPB组、超滤组RI均增大、OI均减小;改良超滤组与CPB组比较在T3时点RI值减小、OI值增大,差异均有统计学意义(P＜0.05),T2时点差异无统计学意义.结论 体外循环中应用改良超滤可提高氧合指数,降低呼吸指数,减轻肺组织炎症反应,从而改善术后肺功能.