罗格列酮对盲肠结扎穿孔脓毒症大鼠肺损伤的影响

目的 观察过氧化物酶体增殖子激活受体γ(peroxisome proliferator-activated receptor γ,PPARγ)激动剂罗格列酮对盲肠结扎穿孔(cecal ligation puncture,CLP)所致脓毒症大鼠肺损伤的影响. 方法 80只健康雄性Wistar大鼠,采用随机数字表法分为5组(每组16只):假手术组(SHAM组);盲肠结扎穿孔组(CLP组);罗格列酮组(ROSI组),CLP前30 min静脉注射罗格列酮0.3 mg/kg;PPARγ拮抗剂GW9662组(GW组):CLP前30 min静脉注射GW9662 0.3 mg/kg; GW9662+罗格列酮组(GW+ROSI组):依次于CLP前30 min静脉注射GW9662 0.3 mg/kg、CLP前15 min静脉注射罗格列酮0.3 mg/kgo于CLP后6、24 h各组随机抽取8只大鼠处死并留取血液及肺组织.测定各组肺组织湿/干质量比(wet/dry ratio,W/D);肺组织髓过氧化物酶(myeloproxidase,MPO)活性;酶联免疫吸附法(enzyme linked immunosorbent assay,ELISA)测定血浆肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平;实时荧光定量聚合酶链反应(real-time PCR)测定肺组织高迁移率族蛋白B1(high mobility group protein B1,HMGB1)mRNA水平. 结果 CLP组、ROSI组、GW组、GW+ROSI组大鼠W/D比、MPO活性、TNF-α水平以及HMGB 1mRNA水平在CLP后6、24 h增加,均高于SHAM组.CLP后6 h,CLP组、ROSI组、GW组、GW+ROSI组大鼠W/D比、MPO活性、TNF-α 水平以及HMGB1 mRNA水平分别为(5.31±0.14)、(3.15±0.47) U/g、(15.064±0.448) μg/L、(0.758±0.130);(4.33±0.21)、(2.21±0.31) U/g、(3.334±0.212) μg/L、(0.422±0.124); (4.93 ±0.14)、(3.13± 0.28) U/g、(15.001±0.343) μg/L、(0.732±0.198);(4.87±0.13)、(3.08±0.35) U/g、(14.866±0.412)μ g/L、(0.763±0.0 17),均高于SHAM组的(3.98±0.17)、(0.67±0.43) U/g、(0.452±0.033) μg/L、(0.244±0.053) (P＜0.05).CLP后24 h,CLP组、ROSI组、GW组、GW+ROSI组大鼠W/D比、MPO活性、TNF-α 水平以及HMGB1mRNA水平分别为(10.23± 0.19)、(3.61±0.82) U/g、(1.542± 0.193) μg/L、(2.413± 0.211);(6.39 ±0.18)、(2.17±1.02) U/g、(0.947±0.281) μg/L、(1.517±0.076); (10.08±0.26)、(3.45±0.36) U/g、(1.513± 0.210) μg/L、(2.385±0.323); (10.15±0.18)、(3.53 ±0.32) U/g、(1.524±0.180) μg/L、(2.404±0.135),均高于SHAM组的(4.02±0.20)、(0.68±0.34) U/g、(0.429±0.021)μg/L、(0.232± 0.032) (P＜0.05).ROSI组大鼠W/D比、MPO活性、TNF-α 水平以及HMGB1 mRNA水平在CLP后6、24 h与CLP组、GW组、GW +ROSI组分别比较均显著降低(P＜0.05). 结论 罗格列酮可以降低CLP脓毒症大鼠TNF-α水平以及HMGB1mRNA水平,减轻肺水肿程度及炎症损伤程度,对肺损伤具有保护作用.     

促红细胞生成素预先给药对大鼠内毒素性急性肺损伤的影响

目的 探讨促红细胞生成素(EPO)预先给药对大鼠内毒素性急性肺损伤的影响.方法 成年雄性SD大鼠32只,体重180～220 g,随机分为4组(n=8),C组腹腔注射生理盐水4 ml/kg(EPO溶剂对照),30 min后静脉注射生理盐水2 ml/kg[脂多糖(LP3)溶剂对照];EPO组腹腔注射EPO3 000 U/kg,30 min后静脉注射生理盐水2 ml/kg;LPS组腹腔注射生理盐水4 ml/kg,30 min后静脉注射LPS 6 mg/kg;EPO+LPS组腹腔注射EPO 3 000 U/kg,30 min后静脉注射LPS 6 mg/kg.于静脉注射LPS后4 h时处死大鼠,观察肺组织病理学结果 ,计算肺组织湿/干重(W/D)比;测定肺组织髓过氧化物酶(MPO)活性和丙二醛(MDA)、一氧化氮(NO)含量;采用Western blot法测定肺组织诱导型一氧化氮合酶(iNOS)和硝基酪氨酸(NT)的表达.结果 与C组相比,LPS组和EPO+LPs组肺组织W/D比、MPO活性、MDA和NO含量升高,iNOS和NT表达上调(P<0.01);与LPS组相比,EPO+LPS组肺组织W/D比、MPO活性、MDA和NO含量降低,iNOS和NT表达下调(P<0.01).结论 EPO预先给药可减轻大鼠内毒素性急性肺损伤,与其下调iNOS表达,减少NO生成有关.     

过氧化物酶体增殖物活化的受体γ对肝星状细胞作用机制的研究

目的探讨过氧化物酶体增殖物活化受体γ(PPARγ)对肝星状细胞(HSC)生物学特性的影响及其作用机制。方法用MTT法和流式细胞仪检测对照组、罗格列酮组、GW9662+罗格列酮组、GW9662组大鼠肝星状细胞的增殖和凋亡情况;采用RT-PCR方法检测各组PPARγ及Ⅰ型前胶原mRNA表达;用免疫组织化学法和Western blot法检测PPARγ及Ⅰ型胶原蛋白表达;结果罗格列酮组的肝星状细胞增殖率MTY(0．49±0．06)较对照组(1．00±0．045)、GW9662组(0．89±0．043)和罗格列酮+GW9662组(0．78±0．049)明显减弱,凋亡率明显增高(P<0．05);罗格列酮组PPARγmRNA表达(1．63±0．179)显著高于对照组(0．46±0．021)、GW9662组(0．41±0．01)和罗格列酮+GW9662组(0．45±0．20)(P<0．05),罗格列酮组Ⅰ型前胶原mRNA表达(0．32±0．02)与对照组(1．61±0．09)、GW9662组(1．81±0．22)和罗格列酮+GW9662组(1．37±0．01)相比显著降低(t值分别为15．59,14．68,8．07,P<0．01);其他各组之间PPAR-γ和Ⅰ型前胶原mRNA的表达差异无统计学意义(P>0．05)。PPARγ及Ⅰ型胶原蛋白表达所得结果与RT-PCR结果相一致。结论PPARγ特异性激动剂罗格列酮可以增加PPARγ的表达。抑制HSC表达Ⅰ胶原,抑制HSC增殖,诱导HSC凋亡,PPARγ配体对于缓解肝脏纤维化具有一定的作用。     

罗格列酮对大鼠急性胰腺炎肺损伤黏附分子表达的作用

目的 探讨过氧化物酶体增殖物激活受体-γ(PPAR-γ)激动剂罗格列酮(ROSI)对大鼠急性胰腺炎肺损伤(APALI)黏附分子的作用及其机制.方法 雄性Wistar大鼠54只,随机分为假手术组(SO组)、急性胰腺炎组(SAP组)和罗格列酮预处理组(ROSI组).胆胰管逆行注射5%牛磺胆酸钠制备急性胰腺炎模型.ROSI组造模前30 min经股静脉注射10%二甲基亚砜(DMSO)溶解的罗格列酮(6 mg/kg);SO组、SAP组则注射等量10%DMSO.术后3 h、6 h、12 h分批剖杀大鼠,每个时间点6只.检测血清淀粉酶(AMY)、肺组织髓过氧化物酶(MPO)、肺湿干比(W/D),取肺组织行病理学检查;逆转录聚合酶链反应(RT-PCR)检测肺组织细胞间黏附分子-1(ICAM-1)、P-选择素和E_选择素mRNA表达水平.结果 SAP组各时间点AMY、MPO、W/D和肺组织病理评分均较S0组升高(P<0.05);ROSI组上述指标较SAP组下降,AMY、MPO、W/D和病理评分在6 h、12 h差异有统计学意义(P<0.05).SAP组ICAM-1、P-选择素和E-选择素mRNA表达在12 h达高峰,均较SO组12 h升高(P<0.05),ROSI组上述指标mRNA表达在12 h点均较SAP组下降(P<0.05).结论 罗格列酮通过抑制肺组织IcAM-1、P-选择素和E-选择素的表达,减轻急性胰腺炎肺损伤程度.     

罗格列酮对大鼠急性胰腺炎肺损伤黏附分子表达的作用

目的 探讨过氧化物酶体增殖物激活受体-γ(PPAR-γ)激动剂罗格列酮(ROSI)对大鼠急性胰腺炎肺损伤(APALI)黏附分子的作用及其机制.方法 雄性Wistar大鼠54只,随机分为假手术组(SO组)、急性胰腺炎组(SAP组)和罗格列酮预处理组(ROSI组).胆胰管逆行注射5%牛磺胆酸钠制备急性胰腺炎模型.ROSI组造模前30 min经股静脉注射10%二甲基亚砜(DMSO)溶解的罗格列酮(6 mg/kg);SO组、SAP组则注射等量10%DMSO.术后3 h、6 h、12 h分批剖杀大鼠,每个时间点6只.检测血清淀粉酶(AMY)、肺组织髓过氧化物酶(MPO)、肺湿干比(W/D),取肺组织行病理学检查;逆转录聚合酶链反应(RT-PCR)检测肺组织细胞间黏附分子-1(ICAM-1)、P-选择素和E_选择素mRNA表达水平.结果 SAP组各时间点AMY、MPO、W/D和肺组织病理评分均较S0组升高(P<0.05);ROSI组上述指标较SAP组下降,AMY、MPO、W/D和病理评分在6 h、12 h差异有统计学意义(P<0.05).SAP组ICAM-1、P-选择素和E-选择素mRNA表达在12 h达高峰,均较SO组12 h升高(P<0.05),ROSI组上述指标mRNA表达在12 h点均较SAP组下降(P<0.05).结论 罗格列酮通过抑制肺组织IcAM-1、P-选择素和E-选择素的表达,减轻急性胰腺炎肺损伤程度.     

罗格列酮对大鼠急性胰腺炎肺损伤黏附分子表达的作用

目的 探讨过氧化物酶体增殖物激活受体-γ(PPAR-γ)激动剂罗格列酮(ROSI)对大鼠急性胰腺炎肺损伤(APALI)黏附分子的作用及其机制.方法 雄性Wistar大鼠54只,随机分为假手术组(SO组)、急性胰腺炎组(SAP组)和罗格列酮预处理组(ROSI组).胆胰管逆行注射5%牛磺胆酸钠制备急性胰腺炎模型.ROSI组造模前30 min经股静脉注射10%二甲基亚砜(DMSO)溶解的罗格列酮(6 mg/kg);SO组、SAP组则注射等量10%DMSO.术后3 h、6 h、12 h分批剖杀大鼠,每个时间点6只.检测血清淀粉酶(AMY)、肺组织髓过氧化物酶(MPO)、肺湿干比(W/D),取肺组织行病理学检查;逆转录聚合酶链反应(RT-PCR)检测肺组织细胞间黏附分子-1(ICAM-1)、P-选择素和E_选择素mRNA表达水平.结果 SAP组各时间点AMY、MPO、W/D和肺组织病理评分均较S0组升高(P<0.05);ROSI组上述指标较SAP组下降,AMY、MPO、W/D和病理评分在6 h、12 h差异有统计学意义(P<0.05).SAP组ICAM-1、P-选择素和E-选择素mRNA表达在12 h达高峰,均较SO组12 h升高(P<0.05),ROSI组上述指标mRNA表达在12 h点均较SAP组下降(P<0.05).结论 罗格列酮通过抑制肺组织IcAM-1、P-选择素和E-选择素的表达,减轻急性胰腺炎肺损伤程度.     

姜黄素预先给药对内毒素诱导大鼠急性肺损伤的作用

目的 研究姜黄素预先给药对内毒素诱导大鼠急性肺损伤的作用及其可能机制。方法 48只雄性Wistar大鼠，随机分为4组（n=12），对照组（S组）、姜黄素组（C组）分别静脉注射10％二甲基亚砜（DMSO）2 ml／kg、姜黄素40 mg／kg（溶于DMSO），30 min后静脉注射生理盐水2 ml／kg;内毒素组（L组）、姜黄素预先给药组（C-L组）分别静脉注射10％DMSO 2 ml／kg、姜黄素40 mg／kg，30 min后静脉注射脂多糖（LPS）6 mg／kg。注射LPS后4 h处死动物。每组中6只大鼠在处死前15 min静脉注射伊文思蓝（EB）20mg／kg，用于测定肺组织EB含量，每组的其余大鼠用于测定支气管肺泡灌洗液（BALF）中髓过氧化物酶（MPO）活性和中性粒细胞（PMN）计数及肺组织湿干重比（W／D）、MPO活性、PMN趋化因子-1（CINC-1）mRNA、CINC蛋白表达，并在光镜下观察肺组织病理学改变。结果 与S组比较，L组BALF中MPO、PMN计数和肺组织W／D、EB及MPO、CINC-1 mRNA、CINC蛋白水平升高（P〈0．05或0．01），C组上述指标差异均无统计学意义（P〉0．05）;与L组比较，C-L组上述指标均降低（P〈0．05或0．01）。C-L组肺组织病理学损伤较L组减轻。结论 姜黄素40mg／kg预先给药对内毒素诱导急性肺损伤大鼠肺产生一定的保护作用，与下调肺组织CINC-1的表达进而抑制PMN在肺组织的聚集、激活有关。     

雷帕霉素联合罗格列酮对脓毒症大鼠肺损伤的影响

目的 评价雷帕霉素联合罗格列酮对脓毒症大鼠肺损伤的影响.方法 健康雄性Wistar大鼠120只,2月龄,体重250～ 300 g,采用随机数字表法,将其分为5组(n=24):假手术组(S组)、盲肠结扎穿孔组(CLP组)、雷帕霉素组(RPM组)、罗格列酮组(RGZ组)和雷帕霉素+罗格列酮组(RPM+ RGZ组).CLP组、RPM组、RGZ组和RPM+ RGZ组采用盲肠结扎穿孔术法制备大鼠脓毒症模型.术前30 min RPM组于皮下注射雷帕霉素0.4 mg/kg,RGZ组股静脉注射罗格列酮0.3 mg/kg,RPM+ RGZ组皮下注射雷帕霉素0.4 mg/kg联合股静脉注射罗格列酮0.3 mg/kg,CLP组给予等容量生理盐水.于术后2、6、24和48 h时分别处死6只大鼠,取肺组织,行HE染色,光镜下观察,进行肺损伤评分;采用分光光度法检测肺组织髓过氧化物酶(MPO)活性;采用凝胶阻滞电泳分析法检测肺组织信号转导和转录激活因子3(STAT3) DNA结合活性.结果 与S组比较,CLP组、RPM组、RGZ组和RPM+ RGZ组肺损伤评分、肺组织MPO活性和STAT3 DNA结合活性升高(P＜0.05);与CLP组比较,RPM组、RGZ组和RPM+ RGZ组肺损伤评分、肺组织MPO活性及STAT3 DNA结合活性降低(P＜0.05);与RPM组及RGZ组比较,RPM+ RGZ组肺损伤评分、肺组织MPO活性及STAT3 DNA结合活性降低(P＜0.05).结论 与雷帕霉素或罗格列酮单独用药比较,二者联合应用减轻脓毒症大鼠肺损伤的效应更明显,其机制与抑制STAT3信号通路激活有关.     

罗格列酮保护大鼠重症急性胰腺炎肾损伤的机制

目的 探讨高选择性过氧化物酶体增殖物激活受体-γ( PPAR-γ)的激动剂罗格列酮(ROSI)保护大鼠重症急性胰腺炎(SAP)肾损伤的可能机制.方法 将雄性Wistar大鼠54只随机分为假手术组(SO组)、重症急性胰腺炎组(SAP组)和罗格列酮处理组(ROSI组),每组大鼠18只.胆胰管逆行注射5％牛磺胆酸钠制备重症急性胰腺炎模型.ROSI组造模前30 min经股静脉注射10％二甲基亚砜(DMSO)溶解的罗格列酮(6 mg/kg);SO组、SAP组则经股静脉注射等量10％DMSO(0.2 ml/100 g).术后3、12、24h分批剖杀大鼠,每个时间点6只.分别取肾组织检测一氧化氮(NO)及其合成酶(iNOS)的水平和核转录因子-κB( NF-κB)/p65蛋白表达水平,并观察不同时间点组大鼠肾脏肿瘤坏死因子-α( TNF-α)和细胞间黏附分子-1(ICAM-1)的mRNA及蛋白表达.结果 SAP组各时点NO含量分别为(2.34±0.31)、(7.73 ±0.48)、( 17.33±0.89) mg/g;SAP组各时点NF-κB/p65含量分别为30648.11 ±2655.13、53 654.63±3065.94、70 546.85±5046.55;SAP组各时点TNF-α表达水平为4.18±0.61、5.69 ±0.82、11.86±2.49;SAP组各时点ICAM-1表达水平为3.68±0.58、6.48 ±0.76、8.62±1.09,均与SO组各时间点比较显著升高,差异有统计学意义(P＜0.05);ROSI组12、24h时点NO含量分别为(4.10±0.62)、(6.09±0.79) mg/g;ROSI组24h时点NF-κB/p65含量为30468.48±2684.59; ROSI组24h时点TNF-α表达水平为6.60±1.34;ROSI组24h时点ICAM-1表达水平为2.92±0.88,均较SAP组下降,差异有统计学意义(P＜0.05).结论 罗格列酮通过抑制NF-κB的表达,从而减少TNF-和ICAM-1的产生,减轻炎症反应的发生发展,显示其参与了保护重症急性胰腺炎所诱发的肾损伤机制.     

氨基胍对大鼠内毒素性肺损伤的影响

目的 观察诱导型一氧化氮合酶抑制剂氨基胍(AG)对内毒素性肺损伤的影响。方法 采用静脉注射脂多糖(LPS)制备内毒素性肺损伤大鼠模型。将40只SD雄性大鼠随机分为5组：空白对照组、LPS组、AG高剂量(100mg／kg)、中剂量(50mg／kg)、低剂量(25mg／kg)治疗组，LPS组、AG高剂量、中剂量和低剂量治疗组手术后稳定1h静脉注射LPS(5mg／kg)，空白对照组给等量生理盐水，AG高剂量、中剂量和低剂量治疗组于给予LPS 3h后经腹腔给AG，空白对照组和LPS组给等量生理盐水。实验过程中监测平均动脉压(MAP)，于注射LPS后1、3和6h时取静脉血0．4Tnl测定血浆NO浓度，于注射LPS 6h后处死大鼠，迅速取出肺脏，测定肺系数、肺含水量和肺组织中丙二醛(MDA)含量、一氧化氮合酶(NOS)、超氧化物歧化酶(SOD)活性的变化；在光镜下观察肺形态结构的变化。结果 LPS可明显降低MAP，升高肺系数和肺含水量，升高血浆中NO含量，可显著升高肺组织中NOS活性、增加MDA含量、降低SOD活性，引起肺形态结构的病理变化。氨基胍可明显改善吣引起的以上肺损伤，病理变化也表明：AG使肺泡萎陷明显减轻，肺间隔变窄，毛细血管增生不明显，肺间隔炎细胞浸润减轻，且高剂量比低剂量明显。结论 静脉注射LPS(5mg/kg)可成功制备大鼠内毒素性肺损伤模型；氨基胍可减轻内毒素性肺损伤，且随剂量增大作用增强。     

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.     

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.     

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.     

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.     

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.