树突状细胞疫苗对胃癌术后患者外周血白细胞介素12水平及Th1/Th2平衡的影响

目的探讨胃癌患者术后应用树突状细胞(dendritic cells,DCs)疫苗治疗后机体免疫功能的变化.方法采用外周血单个核细胞及自体肿瘤抗原在体外制备DCs疫苗.采用临床随机对照研究将50例胃癌患者分为2组,常规治疗组在胃癌术后予以化疗,疫苗治疗组术后化疗2周后开始进行DCs疫苗皮下注射,共注射4次.在治疗前后相应各时相点采取患者外周血检测白细胞介素12(IL-12)、IL-4及干扰素γ(IFN-γ)的水平.结果疫苗治疗组患者DCs注射前及注射后2周、4周和8周的外周血IL-12的水平分别为(37±4)pg/ml、(68±6)pg/ml、(96±12)pg/ml和(59±9)pg/ml;IFN-γ的水平分别为(61±12)pg/ml、(134±19)pg/ml、(145±20)pg/ml和(111±15)pg/ml;IL-4的水平分别为(55±7)pg/ml、(49±6)pg/ml、(46±5)pg/ml和(50±8)pg/ml.而常规治疗组患者外周血IL-12、IFN-γ及IL-4的水平分别为(39±7)pg/ml、(45±9)pg/ml、(44±10)pg/ml、(44±6)pg/ml;(63±10)pg/ml、(61±13)pg/ml、(62±11)pg/ml、(61±7)pg/ml;(52±11)pg/ml、(55±9)pg/ml、(53±10)pg/ml、(55±8)pg/ml.疫苗治疗组患者外周血IL-12及IFN-γ水平在疫苗治疗后明显提高,与同期正常对照组相比差异有显著意义(P<0.05).结论 DCs疫苗可提高胃癌患者术后外周血IL-12的水平,并促进 T 细胞向Th1方向发展,临床应用无明显不良反应.     

IL-12基因修饰树突状细胞体外诱导免疫杀伤肝癌细胞

目的探讨IL-12基因修饰树突状细胞(DC)体外诱导免疫杀伤肝癌细胞的效能及其机制。方法IL-12基因修饰肝癌病人外周血DC(DC-IL-12),ELISA法检测DC-IL-12培养上清中IL-12和IFN-γ水平,以冻融HepG2所获得的肿瘤相关抗原(TAA)刺激DC-IL-12,MTT法检测TAA负载的DC-IL-12刺激同源T淋巴细胞增殖分化能力,细胞毒试验检测DC-IL-12诱导的细胞毒T淋巴细胞(CTL)及其上清液对HepG2肝癌细胞株的杀伤作用,ELISA法检测CTL上清液IFN-γ水平。结果DC经IL-12基因修饰后48h分泌高水平IL-12(24·35±5·4)pg/ml及IFN-γ(725±30)pg/ml,均显著高于未转染DC组(P<0·01)。DC-IL-12诱导的CTL及其上清液对HepG2均有显著杀伤作用,杀伤率显著高于未转染DC组,分别为(82·43±8·7)%vs(57·4±4·3)%和(76·45±8·5)%vs(18·23±5·3)%(P<0·01),DC-IL-12诱导的CTL上清液IFN-γ水平显著高于未转染DC组,分别为(1125·0±32·7)pg/ml、(281·3±14·7)pg/ml(P<0·01)。结论IL-12基因修饰增强DC体外诱导自体T淋巴细胞产生特异性抗肝癌免疫,其机制与IL-12基因修饰促进DC分泌IL-12、增强T淋巴细胞活化及分泌IFN-γ密切相关。     

大鼠肝移植排斥反应时γ干扰素及白细胞介素10的表达及意义

目的 探讨大鼠肝移植排斥反应时γ干扰素(IFN-γ)及白细胞介素10(IL-10)的表达及意义.方法 采用改良的Kamada"二袖套法"制备大鼠原位肝移植模型,同系移植组供、受者均为SD大鼠;同种异体移植组的供者为Wistar大鼠,受者为SD大鼠;另设假手术组.术后7 d处死动物,观察移植肝脏的组织学变化,检测血清IFN-γ和IL-10的含量,以及移植肝脏内IFN-γ和IL-10 mRNA的表达.结果 同种异体移植组移植肝脏有较多坏死肝细胞,汇管区及中央静脉周围可见以淋巴细胞为主的炎症细胞浸润,胆管上皮细胞可见胞浆空泡变性、核固缩或碎裂,整个肝小叶结构紊乱.同系移植组肝脏组织结构仅有轻度缺血再灌注损伤表现,汇管区有较少炎症细胞浸润,胆管上皮细胞结构和肝小叶结构基本正常.同种异体移植组血清IFN-γ为(386.7±14.4)Pg/ml,明显高于同系移植组的(159.8±16.5)pg/ml(P<0.05);同种异体移植组血清IL-10为(126.3±13.1)pg/ml,明显低于同系移植组的(288.3±17.1)pg/ml(P<0.05).同种异体移植组移植肝组织内IF-γ mRNA表达水平明显高于同系移植组(P<0.05),而IL-10 rnRNA表达水平明显低于同系移植组(P<0.05).结论 大鼠肝移植排斥反应时IFN-γ表达明显升高,IL-10表达明显降低;T_H1/T_H2型细胞因子的动态平衡可能在大鼠肝移植排斥反应中起着重要作用.     

树突状细胞功能异常对结直肠癌肝转移的影响

目的 探讨树突状细胞(DC)功能异常对结直肠癌肝转移的影响及其意义.方法 收集2008年1月至2010年6月健康成年人30例、结直肠癌术前、术后无肝转移者30例和术后肝转移30例患者外周血,分离单核细胞后分别加入GM-CSF(1000 U/ml)、IL-4(1000 U/ml)和'TNF-α(1000 U/ml)诱导分化成熟DC,通过加入HT29大肠癌细胞抗原处理(100 μg/ml)或不处理,DC∶T细胞为1∶10,培养7 d,用ELISA方法测定培养液中IFN-γ和IL-10水平,酶标仪测定CCK8和LDH光密度(OD)值,间接测定T细胞增殖和杀伤能力.结果 结直肠癌术后肝转移患者外周血DC在无肿瘤抗原刺激时与健康人T细胞混合培养液IL-10水平显著低于结直肠癌术前患者和健康人[(11.9±1.3)pg/ml比(29.6±9.7)pg/ml、(23.4±8.0)pg/ml,F=4.475,P＜0.05].结直肠癌术后肝转移患者外周血DC经肿瘤抗原刺激与健康人T细胞混合培养液IFN-γ水平均显著高于结直肠癌术后和健康人[(34 ± 9)pg/ml比(26±12)pg/ml、(24 ±6) pg/ml,F=5.206,P＜0.05].结直肠癌术后肝转移患者DC经HT29肠癌细胞抗原刺激后诱导健康人T淋巴细胞杀伤能力显著高于结直肠癌术前患者和健康成年人[(30.6 ±8.6)pg/ml比(12.1 ± 2.4)pg/ml、(14.9 ±1.7)pg/ml,F=4.147,P＜0.05].结论 结直肠癌患者外周血DC在肿瘤抗原刺激下诱导T淋巴细胞产生IL-10,导致肿瘤免疫逃逸,发生肝转移;外源肿瘤抗原刺激能够提高T淋巴细胞杀伤能力.

Abstract：

Objective To observe the clinical significance and effect of dysfunction of dendritic cell( DC) in colorectal cancer with liver metastasis.Methods Peripheral blood were respectively collected from healthy adult donors (30 cases), preoperative and postoperative coloreatal cancer patients without liver metastasis (30 cases) , and 30 postoperative coloreatal cancer patients with liver metastasis from Jan 2008 to Jun 2010.Peripheral blood mononuclear cells were separated, GM-CSF( 1000 U/ml) , IL-4( 1000 U/ml) and TNF-α ( 1000 U /ml) were added into cell culture fluid to induce the mononuclear cells for mature dendritic cells.There were two subgroups, and in antigen processing subgroup the lysate of HT29 colonic carcinoma cells (100 μg/ml) were added into the cell culture fluid.The T lymphocytes from healthy adults were added into two subgroups by ratio of 1∶10 ( DCs∶ T cells) , cocultured for 7 days.The level of INF-γ and IL-10 in cell culture fluid was assayed with ELISA method.The optical density (OD) of CCK8 ans LDH was assayed with ELIASA to indirectly measure the reproductive activity and the killing efficacy of T lymphocytes.Results The IL-10 level in cocultured fluid of peripheral blood DCs in postoperative colorectal carcinoma patients with liver metastasis and T lymphocytes of healthy adults was significantly higher than that of preoperative patients of colorectal carcinoma and health adults without tumor antigenic stimulation(11.9±1.3) pg/ml vs.(29.6±9.7) pg/ml, (23.4±8.0) pg/ml, F =4.475, P ＜0.05).The IFN-γ level in cocultured fluid of peripheral blood DCs in postoperative colorectal carcinoma patients with liver metastasis and T lymphocytes of healthy adults was significantly higher than that of postoperative patients of colorectal carcinoma and healthy adults with or without tumor antigenic stimulation ( 34 ± 9) pg/ml vs.(26 ± 12 ) pg/ml, (24 ± 6) pg/ml, F = 5.206, P ＜ 0.05).The killing activity of healthy adults T lymphocytes induced by HT29 colonic carcinoma cells in postoperative colorectal carcinoma patients with liver metastasis was significantly higher than that of preoperative patients of colorectal carcinoma and healthy adults (30.6 ±8.6) pg/ml vs.(12.1 ±2.4) pg/ml, (14.9 ± 1.7) pg/ml, F =4.147, P ＜ 0.05).Conclusions T lymphocytes produce IL-10 when indued by DCs from patients with colorectal carcinoma under stimulation of tumor antigen leading to tumor immune escape and liver metastasis.The killing activity of T lymphocytes can be enhanced when stimulated by exogenous tmuor antigen.     

gp96多肽复合物树突状细胞疫苗诱导的体外抗胃癌实验研究

目的研究gp96多肽复合物树突状细胞(DC)疫苗特异性抗胃癌的免疫反应。方法应用层析技术从胃癌组织中提取gp96多肽复合物,制备gp96多肽复合物DC疫苗;采用流式细胞仪检测gp96多肽复合物DC疫苗表面分子的表达;ELISA检测gp96多肽复合物DC疫苗致敏的效应 T淋巴细胞分泌IFN-γ和IL-10的水平;51Cr释放实验检测gp96多肽复合物DC疫苗诱导的特异性对胃癌细胞的杀伤效应。结果gp96多肽复合物DC疫苗表面分子CD1α(79．3±4．1)％、CD80 (84．3±2．4)％、CD83(85．7±3．2)％和HLA-DR(83．4±2．9)％的表达显著增高;对原代培养胃癌细胞的杀伤率(58．5±10．7)％显著高于对SGC 7901细胞的杀伤率(24．0±4．2)％,两者相比差异有统计学意义,P<0．01;对HepG2细胞(13．8±2．8)％则无明显杀伤作用。DC疫苗诱导的效应T淋巴细胞分泌IFN-γ(2875±178)pg／ml的量明显增加,分泌IL-10(36±7)pg／ml的量显著降低。结论 gp96多肽复合物DC疫苗能诱导出较强的对自体胃癌细胞的杀伤作用,且具有高度特异性。     

RNA干扰阻断B7/CD28共刺激通路在小鼠心脏移植中的抗排斥作用

目的探讨RNA干扰(RNAi)技术阻断B7/CD28共刺激通路对小鼠异体心脏移植排斥反应的影响及其机制。方法经体外转录合成针对CD80 mRNA和CD86 mRNA序列特异性小片段干扰RNA(siRNA),转染供者骨髓来源的树突状细胞(DC),半定量逆转录聚合酶链反应、流式细胞仪检测DC转染CD80siRNA、CD86siRNA前后CD80 mRNA和CD86 mRNA的表达水平以及细胞表面CD80及CD86的表达情况。在小鼠异位心脏移植前7d．经静脉给受者输注经siRNA干扰后的DC(干扰DC组),同时设立同种异体对照组、环孢素A(CsA)治疗组(术后皮下注射CsA 5 mg/d)、同系移植对照组和未干扰DC组(移植前输注未转染DC),观察各组移植心脏的存活时间,对移植物的排斥反应进行病理分级,并测定移植物组织中白细胞介素2(IL-2)、γ干扰素(IFN-γ)及IL-10的mRNA表达水平。结果siRNA转染DC后,其CD80 mRNA及CD86 mRNA的表达受到明显抑制,CD80、CD86的阳性率分别由84%和67%下降至35%和30%。与同种异体对照组和未干扰DC组比较,干扰DC组移植心脏存活时间明显延长(P＜0．01),组织排斥反应病理分级显著降低(P <0．01),移植心脏组织中IL-2 mRNA和IFN-γmRNA的表达水平明显降低(P＜0．01),而IL-10 mRNA的表达水平明显升高(P＜0．01)。结论利用RNAi敲减供者骨髓来源的DC表面B7分子的表达,以阻断B7/CD28共刺激通路,具有抑制小鼠心脏移植排斥反应的作用,其机理可能是通过诱导T淋巴细胞无能并使T辅助细胞分化向T_H2型方向偏移。     

白细胞介素-12干扰RNA转染树突状细胞对淋巴细胞增殖的影响

目的 观察白细胞介素(IL)-12两亚基(IL-12p35、IL-12p40)干扰RNA(IL-12p35siRNA、IL-12p40siRNA)重组腺病毒载体感染树突状细胞(DC)后对淋巴细胞增殖的影响.方法 用重组腺病毒载体(IL-12p35siRNA、IL-12p40siRNA、阴性对照HKsiRNA)感染DC,之后与同种小鼠T细胞行混合淋巴细胞培养,并测定上清液中IL-4和干扰素(IFN)-γ浓度以及淋巴细胞增殖反应.结果 IL-12p35siRNA、IL-12p40siRNA重组腺病毒载体分别感染树突状细胞后,只有IL-12p35siRNA重组腺病毒载体感染DC在混合淋巴细胞培养中引起的淋巴细胞增殖能力最低,并导致混合培养上清液中IL-4的上升和IFN-γ的下降.结论 IL-12p35亚基特异性siRNA抑制DC的共刺激活动,导致在体外TH2偏移.     

他克莫司体外诱导狼疮性肾炎患者耐受性树突状细胞形成

目的:观察他克莫司(tacrolimus)处理前后狼疮性肾炎(LN)患者外周血树突状细胞(dendriticcells,DCs)表面标志及功能的改变。方法:分离LN患者外周血单个核细胞,用GM-CSF、IL-4等细胞因子诱导DCs成熟,他克莫司组在加入上述细胞因子前先加入他克莫司(5μg/ml)培养。培养第9d收集DCs细胞,流式细胞仪检测CD80、CD86和HLA-DR的表达。MTT法检测DCs刺激淋巴细胞增殖能力,ELISA法检测混合淋巴细胞反应培养上清IL-10和IFN-γ水平。结果:他克莫司处理后的DCs表达CD80、CD86和HLA-DR百分数较对照组均明显降低(52.70±1.77vs78.36±4.80,63.50±14.06vs83.91±9.81,70.41±12.51vs90.51±8.63),P均<0.01;他克莫司处理后的DCs与T细胞混合培养,其刺激T细胞增殖相应的OD值明显降低(DC∶TC=1∶10时,0.294±0.094vs0.582±0.123;DC∶TC=1∶50时,0.325±0.099vs0.458±0.080),P均<0.01。其混合培养的上清液中IL-10水平较无他克莫司处理的DCs与T细胞的混合培养上清液明显降低[(195.0±36.9)pg/mlvs(423.6±93.2)pg/ml,P<0.01],而IFN-γ两者间无统计学意义[(88.2±11.6)pg/mlvs(86.9±12.7)pg/ml,P>0.05]。结论:他克莫司在体外可抑制LN患者外周血DCs的成熟,且他克莫司处理后的DCs能明显抑制T细胞增殖及T细胞向Th2细胞转化。     

肝星状细胞对同种异体胰岛移植物的保护作用

目的 研究小鼠肝星状细胞对同种异体胰岛移植物的保护作用.方法 将糖尿病小鼠随机分为三组,分别为糖尿病组、单纯胰岛移植组及与肝星状细胞共同移植组.单纯移植组于肾被膜下移植入同种异体胰岛300个;共同移植组移植入肝星状细胞(3×105个)与同种异体胰岛(300个)混合物.分别于移植术后监测受体小鼠血糖值及正常血糖维持时间;血糖正常一周后移植组及糖尿病组小鼠分别采血检测血清中TGF-β,TNF-α,IL-1β,IFN-γ的含量,同时取出移植物进行免疫组织化学检测.结果 术后共同移植组受体正常血糖维持时间为(23.75±8.96)d,单纯胰岛移植组受体正常血糖维持时间为(11.9±6.92)d,差异有统计学意义(P<0.05);三组受体血清中TNF-α、IL-1β、IFN-γ含量差异无统计学意义(P>0.05),共同移植组受体血清中TGF-β含量为(2292.31±5.87)pg/ml,单纯移植组为(1246.55±38.91)pg/ml,两组比较差异有统计学意义(P<0.05);病理学结果显示共同移植组胰岛素表达量大,并且在移植物周围有生物包膜形成.结论 在同种异体移植模型中,肝星状细胞可能通过高分泌TGF-β、局部形成包囊等方式保护胰岛移植物并延长其存活时间.     

miRNA-155／PU.1信号通路阻滞对大鼠骨髓来源树突状细胞成熟及移植免疫的影响

目的探讨miRNA-155／PU-1信号通路阻滞对骨髓来源树突状细胞（DCs）成熟及其对应用于大鼠小肠移植中的免疫功能的影响。方法利用贴壁法培养诱导DCs,针对miRNA-155／PU-1信号通路中关键转录因子PU．1基因设计并合成3对PU．1siRNA（Pu．1沉默组、阴性对照组及对照组）,用脂质体法转染细胞,并筛选一对高沉默效率PU．1siRNA。流式细胞术分析PU．1沉默组、阴性对照组及对照组细胞表面CD80、CD86及主要组织相容性复合体（MHC）-II的表达;ELISA法检测上清液中IL．10及IL．12p70的水平;混合淋巴细胞反应检测对同种异体T淋巴细胞的增殖作用;在大鼠小肠移植前7d经受体尾静脉等量注射3组细胞,移植后观察各组受体存活情况及移植物病理情况。结果①DCs表面分子CD80、CD86和MHC一1I表达率在PU．1沉默组分别为（27．0±5．6）％、（23．6＋4．8）％及（36．8±6．8）％,阴性对照组分别为（74．0±9．4）％、（76．5±8．7）％及（87．8±11．3）％,PU．1沉默组均分别明显低于阴性对照组（尸〈0．05）。②PU．1沉默组IL．10水平较阴性对照组明显升高（尸〈0．05）,IL-12p70则明显降低（尸〈0．05）。③PU．1沉默组DCs刺激同种异体T淋巴细胞增殖也较阴性对照组明显降低（尸〈0．05）。④将PU．1沉默组DCs术前注入受体行大鼠小肠移植后,受体平均存活时间为（14．3±3．3）d,明显长于阴性对照组的（7．8±1．5）d（尸〈0．05）和对照组的（8．0＋2．5）d（P〈0．05）,且术后5d时移植物病理显示移植肠组织轻度淋巴细胞浸润和绒毛水肿。结论体内外实验表明,miRNA-155／PU．1信号通路阻滞的DCs成熟度明显受到抑制,并能稳定发挥诱导受体特异性免疫耐受的作用。     

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.     

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.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.