miR-96的表达对肝细胞癌细胞迁移和侵袭的影响

目的:探讨miR-96在肝细胞癌(HCC)细胞中的表达及作用。方法:用qRT-PCR测定miR-96在不同HCC细胞系(HepG2、7721、huh7)及正常肝细胞系L02中的表达;将HepG2细胞分别转染miRNA随机序列(阴性对照组)、miR-96模拟物(miR-96模拟物组)和miR-96抑制物(miR-96抑制物组)后,用细胞划痕实验及Transwell细胞侵袭实验分别检测细胞迁移及侵袭能力,qRT-PCR及Western blot分别测定PTPN9 mRNA及蛋白的表达。结果:miR-96在各肝癌细胞系中的相对表达量均明显高于其在正常肝细胞系L02的相对表达量(均P0.01)。与阴性对照组比较,细胞划痕愈合率在miR-96模拟物组明显升高,而在miR-96抑制物组明显降低(均P0.05);侵袭细胞数在miR-96模拟物组明显增多,而在miR-96抑制物组明显减少(均P0.05);PTPN9 mRNA与蛋白相对表达量在miR-96模拟物组均明显下调,而在miR-96抑制物组均明显上调(均P0.05)。结论:miR-96在HCC细胞中表达升高,并可能通过下调PTPN9表达促进HCC细胞的迁移与侵袭。     

miR-150-5p抑制肝癌细胞的迁移和侵袭及其机制

目的:探讨mi R-150-5p在肝细胞癌(HCC)细胞迁移与侵袭中的作用及其调控机制。方法:用荧光定量PCR测定mi R-150-5p在正常肝细胞系L02及HCC细胞系Hep G2中的表达;将Hep G2细胞分成两组,分别转染mi R-150-5p(mi R-150-5p组)与随机序列(对照组),转染后,分别用细胞划痕实验、Transwell小室基质渗透实验检测细胞的迁移和侵袭能力,用Western blot检测细胞基质金属蛋白酶2(MMP2)和基质金属蛋白酶9(MMP9)的蛋白表达。结果:mi R-150-5p的表达量在Hep G2细胞系中明显降低,为L02细胞系的0.26倍(P0.01)。转染后,mi R-150-5p组的mi R-150-5p水平明显升高,为对照组的9.53倍(P0.001);mi R-150-5p组的细胞划痕愈合率明显低于对照组(54.63%vs.87.51%,P0.01),细胞侵袭数明显少于对照组(138个vs.452个,P0.01);MMP2与MMP9蛋白表达量均明显低于对照组(0.78 vs.1.75;0.82 vs.1.85,均P0.05)。结论:mi R-150-5p在HCC细胞中表达降低,升高mi R-150-5p的表达可抑制HCC细胞的迁移和侵袭,机制可能与其下调MMP2和MMP9表达有关。     

miR-141-3p在肝细胞癌组织中的表达及其靶基因与肝细胞癌恶性特征的关系

目的观察微小RNA(miRNA,miR)-141-3p在肝细胞癌(HCC)组织中的表达及其对肝癌细胞增殖、迁移和侵袭能力的影响。方法通过生物信息学软件筛选到可能靶向调控高尔基体蛋白73(GP73)基因的hsa-miR-141-3p,并以双荧光素酶报告基因实验验证存在靶向关系。采用实时荧光定量PCR(qRT-PCR)和Western blot方法分别检测HCC细胞系、HCC组织及癌旁组织中的miR-141-3p与GP73分子的表达水平,并分析HCC组织中miR-141-3p表达与HCC临床病理学特征的关系。采用噻唑蓝(MTT)、EdU及Transwell实验观察miR-141-3p过表达对HCC细胞增殖、迁移及侵袭能力的影响。结果 miR-141-3p在HCC组织中的表达水平低于癌旁组织(P0.05),GP73 mRNA及其蛋白则相反(P0.05);HCC组织中miR-141-3p的表达水平与GP73 mRNA的表达水平呈负相关,且miR-141-3p的低表达与血管侵犯、肿瘤分化等级及临床TNM分期密切相关(P0.05)。MTT结果显示,Huh-7细胞转染miR-141-3p过表达质粒后,各时点吸光度(A)值低于空白对照组和miR-NC组(P0.05);EdU检测结果表明,转染miR-141-3p后,Huh-7和MHCC-97H细胞的EdU阳性细胞比低于空白对照组和miR-阴性对照(NC)组(P0.05);Traswell检测结果表明,转染miR-141-3p后,MHCC-97H细胞的侵袭细胞数和迁移细胞数低于空白对照组和miR-NC组(P0.05);细胞学功能回复实验结果表明,miR-141-3p+GP73组的侵袭细胞数和迁移细胞数低于空白对照组和miR-NC组,但高于miR-141-3p组和miR-141-3p+GP73-NC组(P0.05)。结论 HCC组织中miR-141-3p呈低表达,且GP73 mRNA表达水平与其呈负相关;低表达miR-141-3p与HCC细胞的侵袭和转移能力密切相关。过表达miR-141-3p能够显著抑制HCC细胞的增殖、侵袭和迁移,逆转miR-141-3p的部分抑制作用可通过恢复表达不含3′非翻译区(UTR)的GP73基因实现。     

microRNA-671-5p在肝细胞癌中的表达及其负向调控丝切蛋白2与上皮细胞-间质转化的关系

背景与目的:近年研究发现,microRNA-671-5p(miR-671-5p)参与了多种恶性肿瘤的发生发展,同时与多种病毒介导的肝损伤相关,但其与肝细胞癌(HCC)之间的关系目前仍未见报道。本研究的目的为观察miR-671-5p在HCC中的表达情况,分析其功能及其与HCC生物学行为及临床病理特征的联系,并初步探讨作用机制。方法:用qRT-PCR检测80例HCC组织及癌旁组织样本、不同HCC细胞系(Hep3B、MHCC-97H、HepG2、SMMC-7721)及人正常肝细胞(L02)中miR-671-5p的表达,且在同时分析TCGA数据库中miR-671-5p在HCC组织与癌旁组织的表达差异。分析miR-671-5p表达量与临床病理因素的关系;用miR-671-5p抑制物敲低MHCC-97H细胞系中miR-671-5p的表后,分别采用CCK-8实验及Transwell实验分别检测HCC细胞转染miR-671-5p抑制物后增殖、侵袭及迁移能力的变化。利用TargetScan及Starbase网站预测miR-671-5p的靶基因,并通过Western blot、双荧光素酶实验及TCGA数据库分析验证。用Western blot观察降低miR-671-5p表达对HCC细胞中miR-671-5p靶基因及上皮细胞-间质转化(EMT)相关蛋白(E-cadherin、N-cadherin、vimentin)表达的影响,以及在此基础上同时敲低靶基因的表达后,以上蛋白表达的变化。结果:miR-671-5p的表达在HCC组织中明显高于其癌旁组织,在各种HCC细胞系中均明显高于正常肝细胞,且随着样本肿瘤分期与HCC细胞的侵袭力的增加而升高(均P0.05);TCGA数据库分析也显示,miR-671-5p在HCC组织中的表达量明显高于癌旁组织(P0.05)。miR-671-5p的表达水平与AFP水平、肿瘤数目、静脉侵犯、Edmondson-Steiner分级及TNM分期明显有关(均P0.05)。转染miR-671-5p抑制物后,MHCC-97H细胞的增殖、侵袭及迁移能力均明显降低(均P0.05)。生物信息学分析及双荧光素酶实验均显示丝切蛋白2(CFL2)是miR-671-5p潜在靶基因,TCGA数据库分析也显示miR-671-5p与CFL2的表达呈负相关(均P0.05)。降低MHCC-97H细胞中miR-671-5p的表达后,CFL2蛋白的表达水平升高,同时EMT相关蛋白表达明显降低(均P0.05),但同时干扰CFL2的表达后,以上变化均有明显程度的逆转(均P0.05)。结论:miR-671-5p在HCC中表达上调,且与HCC的不良临床病理特征密切相关。miR-671-5p可促进HCC细胞的增殖、侵袭、迁移,其机制可能与抑制CFL2的表达而促进EMT发生有关。     

肝细胞癌中miR-942-5p的表达及其与患者恶性特征及不良预后的关系

目的:探讨微小RNA-942-5p(miR-942-5p)在肝细胞癌(HCC)组织中的表达及其功能。方法:用实时定量PCR检测西安交通大学第一附属医院样本库保存的73例HCC组织和对应癌旁组织中miR-942-5p的表达。分析miR-942-5p表达与HCC患者临床病理资料的关系,同时分析TCGA数据库中miR-942-5p表达与HCC患者总生存率的关系。Transwell小室检测干扰miR-942-5p表达后HCC细胞迁移和侵袭能力的变化,StarBase V3.0网站和荧光素酶报告基因质粒预测分析miR-942-5p的下游靶点,并用Western blot验证。结果:miR-942-5p表达量在HCC组织中明显高于对应癌旁组织(2.390 vs. 1.764,P0.05)。miR-942-5p表达量与HCC患者肿瘤数目、血管浸润和临床分期明显有关(均P0.05)。miR-942-5p高表达HCC患者总生存率明显低于miR-942-5p低表达HCC患者(19.535%vs. 53.873%,P0.05)。沉默miR-942-5p表达后,肝癌HCCLM3和MHCC97H细胞迁移和侵袭能力明显减弱(均P0.05)。预测与分析结果显示,扣针蛋白5(FBLN5)是miR-942-5p的直接下游靶点(P0.05),沉默miR-942-5p表达导致HCCLM3和MHCC97H细胞中FBLN5表达增加。结论:miR-942-5p在HCC组织中表达异常升高并与恶性临床特征和不良预后密切相关,机制可能与miR-942-5p抑制FBLN5表达促进HCC细胞迁移和侵袭有关。     

miR-184靶向AGO2调控AKT/mTOR信号通路对膀胱癌细胞增殖、迁移及侵袭能力的影响

目的 研究miR-184在膀胱癌发生、发展过程中的作用及其相关机制。方法 收集2015年1月至2017年1月南阳市中心医院87例膀胱癌患者的手术切除标本,采用qRT-PCR检测膀胱癌及癌旁组织中miR-184的表达;通过生物信息学方法预测miR-184的靶基因并采用双荧光素酶实验及免疫荧光进行验证。在人膀胱癌细胞系T24中转染miR-184过表达质粒,MTT、Transwell侵袭和划痕实验检测细胞增殖、侵袭和迁移能力,Western blot检测AKT/mTOR通路蛋白的表达。结果 miR-184在膀胱癌组织中的相对表达水平1.238±0.026明显低于癌旁组织2.601±0.054,差异有统计学意义(t=22.57,P0.01);且其表达水平与膀胱癌患者的TNM分期(t=-5.61,P0.001)、淋巴结转移(t=-2.35,P=0.011)及组织学分级存在明显相关(t=2.171,P=0.033)。生物信息学预测及双荧光素酶报告基因实验证实miR-184能直接靶向结合AGO2基因3′-UTR。体外实验结果表明,转染miR-184模拟物后,膀胱癌细胞T24中AGO2mRNA和蛋白的表达水平明显下调,细胞增殖、迁移及侵袭能力降低,p-mTOR、p-AKT蛋白表达降低(P0.05)。结论 miR-184在膀胱癌组织中低表达,上调miR-184表达可抑制细胞的增殖、侵袭和迁移能力,其作用机制可能与AKT/mTOR信号通路的调节有关。     

miR-301a在结肠直肠癌组织中的表达及其对结肠癌细胞侵袭、迁移能力的影响

目的:分析结肠直肠癌组织miR-301a的表达及其与结肠直肠癌病人临床病理特征的关系。探讨下调miR-301a表达对结肠癌细胞增殖、侵袭、迁移能力以及PTEN蛋白表达的影响。方法:应用实时定量PCR方法检测48对结肠直肠癌组织和癌旁组织以及5种结肠癌细胞株中miR-301a的表达。应用瞬时转染方法将miR-301a抑制剂转入结肠癌细胞株HCT116后,用细胞增殖实验(CCK-8法)、transwell侵袭实验检测细胞的增殖和侵袭力;采用transwell迁移实验和划痕实验检测细胞迁移能力;并用Western印迹技术检测下调miR-301a后其靶蛋白PTEN表达的变化。结果:PCR结果显示,miR-301a在有淋巴结转移的结肠直肠癌组织中表达较其对应的癌旁组织和无淋巴结转移的癌组织为高(P<0.05);5种结肠癌细胞中均有不同程度表达;transwell侵袭、迁移实验显示,miR-301a抑制剂转染后HCT116细胞侵袭、迁移能力明显降低(P<0.05);增殖实验显示,下调miR-301a对结肠癌细胞抑制作用明显(P<0.05)。划痕实验表明,miR-301a抑制剂转染组细胞迁移能力明显受到抑制。Western印迹法显示,miR-301a抑制剂转染组细胞PTEN蛋白表达增加。结论:miR-301a在有淋巴结转移的结肠直肠癌组织中表达较高;下调miR-301a的表达抑制HCT116细胞的增殖、侵袭和迁移能力,且PTEN蛋白表达增加。miR-301a对结肠癌细胞生物学功能的影响可能是通过PTEN信号通路实现的。     

miR-342-5p 调控靶基因Merlin 表达促进肝细胞癌侵袭转移的实验研究

目的：探讨miR-342-5p及其可疑靶基因Merlin在肝细胞癌（HCC）中表达及意义。 方法：用qRT-PCR检测miR-342-5p和Merlin mRNA在HCC组织与癌旁组织，以及正常肝细胞系与各种不同HCC细胞系中的表达；用重组慢病毒包装质粒pGCSIL-GFP-miR-342-5p或空载体（阴性对照）转染HCCLM3细胞，以无处理的HCCLM3细胞作为空白对照，划痕愈合及Transwell实验观察细胞侵袭运动能力；Western blot法检测细胞中Merlin蛋白的表达。采用双荧光素酶基因报告系统，将含野生型或突变型Merlin基因3''UTR质粒（psiCHECK-Merlin）分别与pGCSIL-GFP-miR-342-5p、空载体（阴性对照）共转染或单独转染（空白对照）HCCLM3细胞后，检测各组细胞荧光素酶活性。 结果：与癌旁组织比较，HCC组织中miR-342-5p表达明显上调，Merlin mRNA表达明显下调（均P<0.05）；HCC组织中，血管侵犯组较无血管侵犯组miR-342-5p表达明显上调，Merlin mRNA表达明显下调（均P<0.05），且miR-342-5p与Merlin mRNA表达呈负相关（r2=5.364，P<0.05）。各HCC细胞系中miR-342-5p表达均明显高于正常肝细胞系，且miR-342-5p的表达随HCC细胞系的侵袭性增高而上调，而Merlin mRNA表达则呈相反趋势（均P<0.05）。与空白对照组及阴性对照组比较，HCCLM3细胞转染pGCSIL-GFP-miR-342-5p质粒后，细胞侵袭运动能力明显下降（均P<0.05），而Merlin蛋白表达明显上调。psiCHECK-Merlin野生型与pGCSIL-GFP-miR-342-5p质粒共转染HCCLM3细胞后，细胞的荧光素酶活性较其阴性对照组或空白对照组明显降低（P<0.05），而psiCHECK-Merlin突变型与pGCSIL-GFP-miR-342-5p质粒共转染HCCLM3细胞后，细胞的荧光素酶活性与其空白对照组或阴性对照组无统计学差异（P>0.05）。 结论：Merlin是miR-342-5p的靶基因，miR-342-5p可能通过调控MerlinmRNA的表达促进肝细胞癌侵袭转移。     

上调miR-449a表达对肝癌细胞生长和侵袭能力的影响

目的:探讨miR-449a在肝癌(HCC)细胞中的表达及其对HCC细胞生物学行为的影响。方法:用qRT-PCR检测miR-449a在正常肝细胞L02和4种HCC细胞株(HepG2、Hep3B、SMMC-7721和Bel-7402)的表达。用脂质体法将miR-449a模拟物或阴性对照序列转染HCC细胞后,分别用CCK-8法、流式细胞术、Transwell小室实验检测细胞增殖、细胞周期、侵袭能力的变化,并观察以上两种不同转染的HCC细胞在裸鼠体内的成瘤情况。结果:miR-449a在4种HCC细胞株的表达水平均明显低于L02细胞(均P0.05),其中在Bel-7402细胞表达的水平最低。与转染阴性对照序列的Bel-7402细胞比较,转染miR-449a模拟物的Bel-7402细胞增殖活性明显降低、G_1/S期阻滞明显增加、穿室细胞数明显减少(均P0.05);与转染阴性对照序列的Bel-7402细胞比较,转染miR-449a模拟物的Bel-7402细胞在裸鼠体内成瘤后的移植瘤质量与体积均明显减小(0.748 g vs.1.234 g;33.667 mm~3 vs.1 400.500 mm~3,均P0.05)。结论:HCC细胞中miR-449a表达降低,上调miR-449a表达可以抑制HCC细胞在体内外的生长。     

MicroRNA-766-3p靶向调控SIRT6抑制肝癌进展的实验研究

目的:探究miR-766-3p是否可通过调节靶基因SIRT6影响肝细胞癌(HCC)的发生与发展进程。方法:RT-PCR及Western blot检测miR-766-3p及SIRT6在HCC组织及癌旁组织中的表达;CCK-8、流式凋亡检测技术、划痕实验及Trans well小室检测miR-766-3p/SIRT6对HCC细胞生长、凋亡、转移及侵袭能力的影响;荧光报告基因实验及western blot技术检测miR-766-3p对SIRT6表达的影响。结果:miR-766-3p在HCC组织中低表达,而SIRT6高表达。过表达miR-766-3p通过与SIRT6的3’UTR区结合降低SIRT6的表达。上调miR-766-3p明显抑制HepG2细胞增殖、转移及侵袭能力,促进细胞凋亡;但SIRT6过表达后终止miR-766-3p的以上作用。结论:miR-766-3p通过靶向负调控SIRT6的表达抑制HCC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.     

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.     

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.     

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.     

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.     

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.     

The analgesic effect of racemic ketamine in patients with chronic ischemic pain due to lower extremity arteriosclerosis obliterans

Background : Ketamine in sub-dissociative doses has been shown to have analgesic and phantom-Limb pain, where conventional treatment has often failed. Chronic ischemic pain due to lower extremity arteriosclerosis obliterans often responds poorly to analgesics, and the pain-generating mechanisms are not well understood.
Methods : Eight patients with rest pain in the lower extremity due to arteriosclerosis obliterans were given sub-dissociative doses of 0.15, 0.30, or 0.45 mg/kg racemic ketamine and morphine 10 mg as a 5-min infusion on four separate days in a cross-over, double-blind, randomised protocol. Plasma levels of (S)- and (R)-ketamine and their nor-metabolites were analysed with an enantioselective high-performance liquid chromatography (HPLC) method. Pain levels were evaluated with a visual analogue scale (VAS).
Results : Individual pain levels were highly variable during and after all the infusions but the pooled pain levels showed a dose-dependent analgesic effect of ketamine with a transient but complete pain relief in all patients at the highest dose (0.45 mg/ kg). Side-effects, mainly disturbed cognition and perception, were pronounced and dose-dependent. Morphine 10 mg had an analgesic peak at 20 min and 5/8 patients had complete pain relief. The remaining 3 patients also had high baseline pain scores, indicating a higher analgesic potency for the 0.30 and 0.45 mg/ kg ketamine doses than for morphine 10 mg.
Conclusion : We have demonstrated a potent dose-dependent analgesic effect of racemic ketamine in clinical ischemic pain. Due to a narrow therapeutic window, this analgesic effect is probably best utilised in combination with other analgesics.