肿瘤坏死因子α基因启动子多态性与肾移植术后急性排斥反应的关系

目的　探讨肿瘤坏死因子α(TNF α)基因启动子 3 0 8位多态性在预测肾移植术后急性排斥反应中的意义。　方法　酶联免疫吸附试验检测 3 5例肾移植患者术前外周血细胞分泌的TNF α水平 ,应用限制性片段长度多态性 (PCR RFLP)方法检测TNF α基因启动子 3 0 8位多态性 ,分析其与术后急性排斥反应的关系。　结果　TNF α启动子 3 0 8位为A/A、A/G基因型者TNF α水平分别为(62 4.96± 177.78)pg/ml、(5 44 .3 2± 13 2 .42 )pg/ml,明显高于G/G基因型者的 (2 3 3 .16± 2 5 .3 7)pg/ml,P<0 .0 1。在HLA DR错配情况下 ,TNF α高分泌基因型受者有 5例 (5 0 % )术后发生急性排斥反应 ,而低分泌基因型受者仅有 2例 (8% )发生急性排斥反应 (P =0 .0 12 )。　结论　肾移植受者TNF α基因启动子 3 0 8位多态性与体外细胞因子产生水平有关 ,TNF α高分泌基因型是术后 3个月内发生急性排斥反应的高危因素     

外周血淋巴细胞穿孔素和颗粒酶B在肾移植急性排斥诊断中的价值

目的　探讨外周血淋巴细胞 (PBLs)中穿孔素 (P)和颗粒酶B (GB)表达水平在同种异体肾移植急性排斥诊断中的价值。　方法　定量RT PCR方法测定 10例肾移植患者移植前后PBLs中P和GB的表达情况 ,并对 3例患者急性排斥反应前后的P和GB表达情况进行对比分析。　结果　 10例患者肾移植前后P的相对表达量分别为 2 3 5± 42和 2 16± 3 5 ,GB分别为 62± 2 3和 5 7± 2 6,差异均无显著性意义 (P >0 .0 5 )。 3例发生急性排斥反应后P、GB相对表达量分别为 193 2± 3 2 6和 489± 5 7,均显著高于发生排斥反应前 (P <0 .0 0 1)。　结论　定量RT PCR测定外周血淋巴细胞中穿孔素和颗粒酶B表达可以较敏感预测肾移植急性排斥反应的发生 ,具有临床诊断参考价值     

达昔单抗预防肾移植术后急性排斥反应的效果

目的　探讨达昔单抗 (Dac ,赛尼哌 )在预防肾移植术后急性排斥反应中的作用。　方法　 2 92例肾移植患者随机分为达昔单抗治疗组 (94例 )与对照组 (198)例 ,分析 2组移植肾功能、急性排斥反应发生情况以及外周血T细胞亚群的变化。　结果　术后 1、6及 12个月时达昔单抗组移植肾功能优于对照组 ,术后 12个月时 2组SCr浓度分别为 (133.2± 4 6 .8)和 (16 5 .7± 5 5 .2 ) μmol/L ,差异有统计学意义 (P <0 .0 5 )。术后 6个月时达昔单抗组急性排斥反应发生率为 2 3.4 % ,对照组为38.4 % ,差异有统计学意义 (P <0 .0 5 ) ;术后 2组CD+ 3 与CD+ 4 表达均下降 ,但差异无统计学意义 (P>0 .0 5 )。　结论　达昔单抗可以降低急性排斥反应发生率 ,改善移植肾功能 ,对T细胞亚群无明显影响。     

尿穿孔素和粒酶B mRNA检测在诊断移植肾急性排斥反应中的意义

目的　探讨尿穿孔素、粒酶BmRNA检测在诊断移植肾急性排斥反应中的作用价值。　方法　应用竞争PCR方法对 34例肾移植患者 4 5份尿样中的穿孔素和粒酶BmRNA进行定量检测。　结果　急性排斥反应组 (n =10 )尿中穿孔素mRNA值 (1.2± 0 .4 )fg/μg总RNA ,粒酶BmR NA值 (1.1± 0 .5 )fg/μg总RNA ,显著高于非排斥组 [n =2 4 ,分别为 (- 0 .6± 0 .3)fg/μg总RNA和(- 0 .8± 0 .2 )fg/μg总RNA],P <0 .0 0 1。尿中细胞毒性分子mRNA水平与急性排斥反应发生时间和严重程度 (Banff分类级别 )无显著相关。当穿孔素mRNA值为 0 .9fg/μg总RNA时 ,诊断急性排斥反应的灵敏度和特异度分别为 85 %和 83% ,粒酶BmRNA值为 0 .4fg/μg总RNA时 ,诊断急性排斥反应的灵敏度和特异度分别为 81%和 78%。　结论　尿中穿孔素及粒酶BmRNA水平检测可以监测和诊断急性排斥反应的发生。     

前列腺癌患者血清胰岛素样生长因子-1检测的临床意义

目的　探讨血清胰岛素样生长因子 1(IGF Ⅰ )与前列腺癌 (PCa)发生发展的关系。　方法　采用免疫放射分析法 (IRMA)检测 3 7例PCa、3 5例良性前列腺增生 (BPH)患者和 2 0例健康人血清IGF Ⅰ ,比较各期PCa血清IGF Ⅰ水平 ,并对 8例行根治性前列腺全切术后患者手术前后IGF Ⅰ水平随访。　结果　PCa组血清IGF Ⅰ ( 3 2 5 .6± 10 0 .8)ng/ml,明显高于BPH组 ( 2 0 1.6± 5 3 .8)ng/ml和健康组 ( 179.0± 5 7.2 )ng/ml,差异有显著性意义 (P <0 .0 1) ;BPH组与健康组比较差异无显著性意义 (P >0 .0 5 ) ;8例PCa患者术前IGF I( 3 15 .8± 87.0 )ng/ml,术后 ( 2 2 4.8± 88.4)ng/ml,差异有显著性意义 (P <0 .0 5 ) ;PCa患者各期血清IGF Ⅰ比较差异无显著性意义 (P >0 .0 5 )。　结论　IGF Ⅰ有可能作为临床上一个新的PCa检测指标预测高危人群 ,进行早期诊断     

大鼠胰腺移植急性排斥反应中调节激活正常T细胞表达和分泌因子的作用

目的　探讨在大鼠胰腺移植急性排斥反应中调节激活正常T细胞表达和分泌因子(RANTES)的作用。方法　对链脲佐菌素诱导的糖尿病大鼠模型施行胰腺移植。术后1、4、7、10d4个时间点取材,采用酶联免疫吸附法检测受体血清RANTES的浓度,免疫组织化学法测定移植胰腺组织RANTES蛋白表达水平。结果　急性排斥反应在术后7d达高峰。术后1、4、7、10d受体血清RANTES浓度在同系移植组分别为(3 5 7.87±63 .2 6)、(2 74.77±5 8.2 2 )、(2 65 .87±43 .40 )、(2 67.5 5±48.91)ng/L ,除1d外与对照组比较差异无统计学意义(2 5 1.18±44 .94)ng/L ;在异系移植组分别为(3 88.48±10 4.45 )、(5 86.72±90 .0 6)、(746.2 8±92 .64 )、(63 1.49±10 6.3 4)ng/L ,与对照组比较差异有统计学意义(P <0 .0 5 )。移植胰腺组织RANTES蛋白的表达强度在同系移植组中与对照组比较无显著变化,而在异系移植组随排斥反应的发展呈动态变化,在4d为中度阳性,至7d表达为强阳性。结论　胰腺移植急性排斥反应过程与RANTES的表达密切联系,移植术后对RANTES进行动态检测有助于胰腺移植急性排斥反应的早期诊断     

特发性无、少精子症病人精浆中性激素水平的测定及意义

目的 :通过测定特发性无、少精子症病人精浆中的性激素水平 ,比较分析精浆性激素与无、少精子症的关系。　方法 :特发性无、少精子症男性各 5 0例 ,正常对照 5 0例。精液常规分析判断精子密度 ,化学发光技术测定精浆性激素水平。　结果 :特发性无、少精子症组黄体生成素 (LH)分别为 (5 .19± 0 .6 7)IU/L和 (4.77± 0 .6 8)IU/L ,与正常组 (2 .19± 0 .2 2 )IU/L相比 ,特发性无精子症组差异有极显著性 (P <0 .0 1) ,特发性少精子症组与正常组相比差异有显著性 (P <0 .0 5 ) ;卵泡刺激素 (FSH)分别为 (1.90± 0 .79)IU/L和 (2 .2 7± 0 .2 5 )IU/L ,与正常组 (1.6 1± 0 .14)IU/L相比 ,差异均有显著性 (P <0 .0 5 ) ;泌乳素 (PRL)分别为 (6 .2 5± 0 .34 )ng/ml和 (6 .33±0 .5 1)ng/ml,与正常组 (6 .36± 0 .32 )ng/ml相比差异均无显著性 (P >0 .0 5 ) ;睾酮 (T)分别为 (1.5 1± 0 .12 )ng/ml和 (1.6 8± 0 .71)ng/ml,与正常组 (1.83± 0 .0 9)ng/ml相比 ,特发性无精子症组差异有显著性 (P <0 .0 5 ) ,特发性少精子症组差异无显著性 (P >0 .0 5 ) ;T/LH的比值分别为 0 .2 9± 0 .0 4和 0 .35± 0 .0 9,与对照组 0 .84± 0 .2 0相比 ,差异均有显著性 (P <0 .0 5 )。　结论 :特发性无、少精子症病人 ,精浆     

内皮细胞因子TM、vWF、凝血因子Ⅶ、Ⅷ和D-二聚体在肝移植排斥反应变化的研究

目的　为了解肝移植出现排斥反应患者内皮细胞因子、凝血因子和纤溶功能的变化 ,了解这些因素在监测排斥反应、疗效和判断预后的作用。方法　随机观察肝移植 4 1例 ,其中出现排斥反应 1 6例 (急性排斥 1 2例、慢性排斥 4例 )。在术前、术后检测血浆血栓调节蛋白 (STM)、血管性血友病因子 (v WF)、因子 V (FV )、V (FV )和 D-二聚体 (D- D)含量。结果　 1有排斥者术前 FVII含量减少 (6 9.2± 7.2 % ) ,D- D含量则升高 (1 .1 9± 0 .2 0 ng/ L) ;2有排斥者术后、排斥前 2天 FVII进一步减少 (分别为 75 .7± 3.1 ,6 0 .7± 4 .5 ) ,而 STM(分别为 5 .5 8± 0 .4 2 m g/ m l,5 .93± 0 .4 5 ng/ m l)、v WF(分别为 1 0 1 .2± 4 .6 % ,1 0 4 .3± 5 .8% ) ;D- D(分别为 2 .89± 0 .75 ,5 .2 8± 0 .81 )则明显升高 ;3急性排斥较慢性排斥 ,冲击治疗无效组与有效组 ,治疗后死亡组与生存组比较 ,STM和 D- D均明显升高。结论　本研究结果初步显示 :1血浆 STM　 v WF、D- D含量增高和FVII含量减少 ,可作为肝移植排斥早期预报指标 ,其中 STM的特异性最高 ;2血 STM、v WF、D- D和 FVII可作为监测肝移植排斥的实验室检测项目和指标 ;3血 STM和 D- D可作为区分急性与慢性排斥、监测冲击治疗疗效和判断预后的指标     

梗阻性黄疸患者血浆可溶性P-选择素与内毒素、D-二聚体的关系及其意义

目的　研究梗阻性黄疸 (梗黄 )患者血浆可溶性P -选择素 (sP selectin ,sP s)与内毒素 (ET )及D -二聚体 (D d)的关系及其意义。方法　应用ELISA和鲎试剂比色法测定梗黄组、急性胆囊炎组和健康人组血浆sP s ,D d和ET含量。结果　健康人组血浆sP s含量为 (93 .43± 17.65 )ng/ml ,ET (0 .0 0 3 0± 0 .0 0 0 4)EU /ml ,D d(0 .3 9± 0 .2 1)mg/L ;急性胆囊炎组血浆sP s含量为 (2 3 3 .3 2± 82 .12 )ng/ml ,ET (0 .40 12± 0 .15 0 6)EU /ml ,D d(0 .76± 0 .2 7)mg/L ;梗黄组血浆sP s含量为 (3 5 1.90± 93 .83 )ng/ml ,ET(0 .3 814± 0 .14 3 0 )EU /ml ,D d(2 .14± 0 .3 7)mg/L。急性胆囊炎组和梗黄组sP s ,D d及ET均高于健康人组 (P <0 .0 1) ;梗黄组ET与急性胆囊组差异无显著性 ,但梗黄组sP s和D d较急性胆囊炎组高 (P <0 .0 1) ,梗黄组的以上二物质含量呈正相关性 (P <0 .0 1) ;急性胆囊炎组sP s与ET呈正相关性 (P <0 .0 1)。协方差分析表明 ,在相同ET含量时 ,梗黄组sP s高于急性胆囊炎组 (P <0 .0 1) ,且与D d有相关性 ,二者有相同变化趋势。结论　胆道梗阻是ET致血管内皮细胞损伤和血小板活化的敏感性因素 ,梗黄患者血液高凝状态与继发性纤溶反应处于动态平衡 ,提示动态监测血浆sP s和D d变化 ,     

他克莫司与环孢素A在尸肾移植中应用的长期疗效和安全性比较

目的　比较他克莫司 (FK5 0 6 )和环孢素A(CsA)在尸肾移植中应用的长期疗效和安全性。方法　 2 10例尸肾移植患者分为FK5 0 6组和CsA组 ,随访 12～ 32个月 ,观察两个组血药浓度变化、急性排斥和慢性排斥反应发生率、人 /肾 1年存活率、血肌酐、肝功能、血糖及血脂水平、药物不良反应、感染发生率以及FK5 0 6逆转顽固性急性排斥反应的效果。结果　血中FK5 0 6和CsA浓度谷值的变化趋势基本相同。FK5 0 6组与CsA组相比 ,急、慢性排斥反应发生率明显降低 (P <0 .0 5 ) ;肝功能异常发生率、高脂血症和牙龈增生发生率以及术后 3个月血肌酐水平均明显降低 (P <0 .0 5 ) ;高血糖和震颤发生率明显升高 (P <0 .0 5 ) ;感染发生率及人 /肾 1年存活率的差异无显著性。结论　与CsA相比 ,FK5 0 6是一种更高效的免疫抑制剂 ,长期使用可以有效降低肾移植后急、慢性排斥反应的发生率 ,有利于移植肾功能的恢复。     

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.     

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.     

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.