骨髓间质干细胞体外定向诱导分化为软骨细胞的实验研究

目的：探讨分离骨髓间充质干细胞（MSCs）并诱导其向软骨细胞转化的体外培养方法,为软骨组织工程的种子细胞来源提供实验依据。方法：抽取兔髂骨骨髓液,经梯度离心法和贴壁法进行体外培养,贴壁细胞传代,取第3代细胞在培养基中添加软骨分化诱导剂[含转化生长因子（TGF-β2）10ng／ml、地塞米松10^7mol／L、维生素C50μmol／L,经7、14、21d诱导培养后,倒置显微镜观察细胞形态,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达。将诱导细胞与软骨支架材料-聚磷酸钙纤维／左旋聚乳酸（CPP／PLLA）复合,1周后终止培养,扫描电镜观察细胞黏附情况。结果：诱导后细胞体外扩增能力显著降低,细胞形态由成纤维样梭形向多角形、多边形或类圆形转变,诱导21d后细胞形态变化最为显著,Ⅱ型胶原免疫组化染色深而均匀。诱导后的MSCs可在支架材料内良好黏附生长。结论：体外培养的MSCs可定向诱导分化为软骨细胞,分泌软骨细胞特异性基质,可用作软骨组织工程的种子细胞。     

转化生长因子-β2体外诱导骨髓间充质干细胞表达软骨细胞表型的观察

目的观察骨髓间充质干细胞(MSCs)在转化生长因子(TGF-β2)诱导下向软骨细胞表型转化的能力,探讨其作为软骨组织工程种子细胞的可能性。方法抽取兔髂骨骨髓液3～4ml,进行原代和传代培养,传代后实验组以高糖DMEM无血清特定培养液诱导,培养液含TGF-β210ng/ml、地塞米松10-7mol/L、维生素C50μmol/L;对照组以高糖DMEM无血清培养液培养,相差显微镜下观察细胞形态变化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达。结果诱导后细胞体外扩增能力显著降低,细胞形态由成纤维样梭形向多角形、多边形或类圆形转变,诱导21d后细胞形态变化最为显著,Ⅱ型胶原免疫组织化学染色深而均匀。结论TGF-β2可有效诱导MSCs向软骨细胞表型转化,分泌软骨细胞特异性基质,有可能成为软骨组织工程较理想的种子细胞来源。     

TGF-β2体外诱导骨髓间充质干细胞表达软骨细胞表型的观察

目的：观察骨髓间充质干细胞（MSCs）在TGF-β2诱导下向软骨细胞表型转化的能力,探讨其作为软骨组织工程种子细胞的可能性。方法：抽取兔髂骨骨髓液3-4ml,进行原代和传代培养,传代后实验组以高糖DMEM无血清特定培养液诱导f含TGF-β2 10ng／ml、地塞米松10^-7M、维生素C50μmol／L）,对照组以高糖DMEM无血清培养液培养,相差显微镜下观察细胞形态变化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达。结果：诱导后细胞体外扩增能力显著降低,细胞形态由成纤维样梭形向多角形、多边形或类圆形转变,诱导21天后细胞形态变化最为显著,Ⅱ型胶原免疫组化染色深而均匀。结论：TGF-β2可有效诱导MSCs向软骨细胞表型转化,分泌软骨细胞特异性基质,有可能成为软骨组织工程较理想的种子细胞来源。     

成人骨髓基质干细胞体外定向诱导分化为软骨细胞的实验研究

目的 建立临床成人骨髓基质干细胞(MSCs)体外培养、定向诱导分化为软骨细胞的途径。方法抽取成人骨髓，Percol密度梯度离心法进行体外培养，贴壁细胞传代，取第3代细胞在培养基中添加软骨分化诱导剂地塞米松、维生素C和不同剂量转化生长因子-β(TGF-β)，培养16d后,在倒置显微镜观察细胞形态，甲苯胺蓝染色蛋白多糖，逆转录一聚合酶链反应(RT-PCR)、免疫细胞化学(SABC法)检测Ⅱ型胶原表达，诱导后MSCs与新型材料聚乳酸和羟基乙醇共聚物(PL-GA)复合。结果 Percoll密度梯度离心法培养可获得均一的。MSCs；5、10ng TGF-β诱导分化的MSCs生长迅速。呈典型的软骨细胞形态，甲苯胺蓝染色阳性，Ⅱ型胶原表达阳性，MSCs对材料PL-GA黏附力强。结论 可以从成人骨髓中培养出MSCs，并可定向诱导分化为软骨细胞，5～10ng TGF-β为最佳诱导剂量，成人MSCs可用作临床自体软骨组织工程种子细胞。     

犬骨髓基质干细胞体外定向分化为软骨细胞

目的 体外诱导犬骨髓基质干细胞(BMSCs)定向分化为软骨细胞，探讨体外诱导成软骨的方法和条件。方法 自犬肋骨取骨髓2～3ml，体外行原代和传代培养扩增，顺序加入碱性成纤维细胞生长因子(bFGF)和转化生长因子β1(TGF-β1)，以培养瓶内较高细胞浓度培养，诱导BMSCs分化为软骨细胞。甲苯胺蓝、阿新蓝染色检测软骨基质的分泌，免疫组织化学染色检测软骨特异性Ⅱ型胶原表达。结果 诱导的软骨样细胞甲苯氨蓝异染性、阿新蓝染色阳性；Ⅱ型胶原免疫组织化学检测阳性。结论 应用bFGF和TGF-β1体外可以诱导犬BMSCs分化为软骨细胞，诱导的软骨细胞可作为软骨组织工程较理想的种子细胞。     

骨髓间质干细胞向软骨细胞表型定向诱导分化的实验研究

目的 研究体外培养的猪骨髓间质干细胞（Bone Marrow Stem Cells,MSCs)在特定培养液作用下向软骨细胞表型转化，探讨其作为组织工程化软骨的种子细胞的可行性。方法 取成年崇明长枫杂交猪髂骨骨髓5ml，在低糖DMEM完全培养液培养2周，传代后以高糖DMEM无血清特定培养液诱导（含胰岛素2mg/L、转铁蛋白3mg/L、丙酮酸100mg/L、地塞米松10^-7mol/L、TGF－β1 10ng/ml)，在相关显微镜和电镜下进行观察，免疫组化检测Ⅱ型胶原分泌，原位杂交检测Ⅱ型胶原mRNA表达。结果 细胞形态由成纤维样梭形向多角形、多边形转变，透视电镜观察见大量扩张粗面内质网、高尔基体、线粒体。诱导培养后第7，14dⅡ型胶原免疫组化阳性，同时原位杂交检测Ⅱ型胶原mRNA表达呈阳性。结论 MSCs在特定培养液诱导下能向软骨细胞表型转化，并能分泌软膏特异性基质，有可能成为软骨组织工程较理想的种子细胞来源的应用前景。     

骨髓基质细胞与关节软骨细胞生物学特性的比较研究

目的观察兔骨髓基质细胞(MSCs)诱导和基因修饰后的主要生物学特性,并与关节软骨细胞进行比较. 方法抽取成年雄性新西兰大白兔髂骨骨髓,密度梯度离心获得骨髓基质细胞,培养传至第5代,按处理方法分为常规培养液组(A组)、条件培养液组(B组)及重组缺陷型腺病毒携带肝细胞生长因子cDNA转染组(C组).条件培养液为常规培养液中含转化生长因子-β1(10 ng/ml)、碱性成纤维细胞生长因子(25 ng/ml)和地塞米松(10-7 mol/L).切取兔膝关节软骨,3 mg/ml Ⅱ型胶原酶消化传代培养至第3代(D组).观察原代MSCs及第5代MSCs(体外培养8～10周后)细胞形态,对第5代MSCs及第3代软骨细胞进行Ⅰ、Ⅱ型胶原免疫组织化学染色,MTT法检测细胞增殖情况.阿利新蓝法检测细胞培养上清液中糖胺多糖(GAG)含量.提取各组培养细胞总RNA,RT-PCR检测Ⅰ、Ⅱ型胶原表达. 结果原代MSCs为短梭形、簇状生长,传代细胞呈长梭形、旋涡样生长.A组细胞爬片Ⅰ型胶原免疫组织化学染色阳性,Ⅱ型胶原免疫组织化学染色阴性,GAG含量低,与D组比较,差异有统计学意义(P＜0.05).B组细胞爬片Ⅰ、Ⅱ型胶原免疫组织化学染色阳性,GAG含量升高,与D组比较差异无统计学意义(P＞0.05);C组转染后第4天增殖率降低,与A组比较差异有统计学意义(P＜0.05),其余时间点各组间无统计学意义(P＞0.05).RT-PCR表明A、B、C组均表达Ⅰ型胶原,B、D组可表达Ⅱ型胶原,C组有较弱的Ⅱ型胶原表达. 结论 MSCs体外培养过程中自然转归趋向于成骨.传代后经向成软骨方向诱导,具有向软骨分化的能力;体外传代培养的MSCs具有干细胞自我增殖和定向分化的特性,可作为靶细胞接受外源目的基因转染并能有效表达.     

软骨细胞与骨髓基质细胞共培养裸鼠体内构建软骨组织的实验研究

目的：探讨软骨细胞在裸鼠体内促进骨髓基质细胞（BMSCs）向软骨分化并形成软骨组织的可行性。方法：从SD大鼠中分别分离出BMSC和软骨细胞进行体外培养。收集软骨细胞培养上清液,作为BMSCs诱导液从第2代开始进行诱导分化,7天后取出标本,免疫组织化学检测软骨特异性Ⅱ型胶原表达,RT-PCR检测Ⅱ型胶原和aggrecan的mRNA表达。SD大鼠BMSCs与软骨细胞按一定比例（7：3）混匀,取5.0×107个混合细胞/ml的各组细胞悬液接种至壳聚糖生物材料,体外培养一周后植入裸鼠皮下,相同数量的单纯软骨细胞或BMSCs同样方法植入,分别作为阳性对照及阴性对照,1.5×107个软骨细胞同样植入作为低浓度软骨细胞对照。各组均8周后取材检测。结果：经诱导后的大鼠BMSCs的Ⅱ型胶原免疫组化检测阳性,RT-PCR检测Ⅱ型胶原和aggrecanmRNA呈阳性表达;混合细胞组及阳性对照组均形成了成熟的软骨,组织学可见成熟软骨陷窝、异染基质及Ⅱ型胶原表达;BMSCs组仅形成了纤维性组织;低浓度软骨细胞组在局部形成了少量软骨。结论：软骨细胞能在一定程度上提供软骨形成的微环境,诱导BMSCs在裸鼠体内向软骨组织分化并形成软骨组织。 还原     

聚磷酸钙纤维／左旋聚乳酸软骨支架复合自体骨髓间充质干细胞构建组织工程化人工关节软骨

目的：应用组织工程学技术,体外初步构建组织工程化人工关节软骨。方法：制备三维多孔软骨支架材料CPP／PLLA,体外诱导兔MSCs向软骨细胞表型分化,免疫组织化学染色检测软骨特异性Ⅱ型胶原表达,将诱导细胞与软骨支架材料CPP／PLLA复合,体外培养构建人工关节软骨,1周后终止培养,扫描电镜观察组织工程化人工软骨的微观结构;同时将构建人工软骨移植于兔大腿皮下,3周后处死动物,甲苯胺蓝染色观察。结果：扫描电镜观察可见该复合材料CPP／PLLA为高孔隙率的网状、连通、微孔结构,微孔分布均匀,孔径大小为300～400μm之间;兔MSCs经体外软骨表型定向诱导后,Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长,细胞被分泌的胶原基质包裹;从体内获取的培养物组织切片观察可见大量的软骨细胞生成,甲苯胺蓝染色阳性。结论：经软骨起源诱导后的MSCs与CPP／PLLA复合培养可以构建自体软骨移植的替代物,为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料,具有较大的潜在应用价值。     

聚磷酸钙纤维和左旋聚乳酸软骨支架复合自体骨髓间充质干细胞构建组织工程化人工关节软骨

目的应用组织工程学技术，体外初步构建组织工程化人工关节软骨。方法制备三维多孔软骨支架材料CPP／PLLA，体外诱导兔MSCs向软骨细胞表型分化，免疫组织化学染色检测软骨特异性Ⅱ型胶原表达，将诱导细胞与软骨支架材料CPP／PLLA复合，体外培养构建人工关节软骨，1周后终止培养，扫描电镜观察组织工程化人工软骨的微观结构；同时将构建人工软骨移植于兔大腿皮下，3周后处死动物，甲苯胺蓝染色观察。结果扫描电镜观察可见该复合材料CPP／PLLA为高孔隙率的网状、连通、微孔结构，微孔分布均匀，孔径大小为300～400Ⅳn之间；兔MSCs经体外软骨表型定向诱导后，Ⅱ型胶原免疫组化染色阳性。诱导后的MSCs可在支架材料内良好贴附生长，细胞被分泌的胶原基质包裹；从体内获取的培养物组织切片观察可见大量的软骨细胞生成，甲苯胺蓝染色阳性。结论经软骨起源诱导后的MSCs与CPP／PLLA复合培养可以构建自体软骨移植的替代物，为应用软骨组织工程方法修复关节软骨缺损和功能重建提供一种新材料，具有较大的潜在应用价值。     

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.     

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.     

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.     

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.     

Intrathecal administration of sameridine to patients subjected to arthroscopic knee joint surgery

Background: Sameridine, a new substance with both local anesthetic and opioid effects, was administered intrathecally for the first time to humans, i. e. in patients subjected to arthroscopic knee joint surgery.
Method: A dose-escalating (10, 15, 20 and 25 mg), open study was performed in 33 patients. Only two patients were included in the 25 mg group.
Results: Sameridine provided good quality of surgical anesthesia in all patients except those receiving 10 mg. The maximum level of sensory block, Th5–Th7, was reached within 30 min with a median duration of 3.6–3.9 h. The motor block was more profound with increasing dose, but never lasted longer than the sensory block. The influence on heart rate and blood pressure was minor and atropine and ephedrine were needed in four patients. No clinically significant ECG-changes were detected and no arrhythmias were recorded. Oxygen saturation and respiratory rate did not decrease in a clinically significant way and were not affected by concomitant morphine given i. v. postoperatively. There were few side-effects, the most frequent being mild pruritus (10/33).
Conclusion: Sameridine provided clinically adequate anesthesia for the patients receiving the doses of 15, 20 and 25 mg. Further studies are needed to evaluate the substance and it is of great interest to clinically investigate the opioid component with respect to postoperative analgesia.     

Reduction of Plasma Fibrinogen, Immunoglobulin G, and Immunoglobulin M Concentrations by Immunoadsorption Therapy with Tryptophan and Phenylalanine Adsorbents

Abstract Immunoadsorption (1A) therapy with tryptophan (TR-350) or phenylalanine (PH-350) adsorbents has been used to reduce the concentration of serum antibodies in human lymphocyte antigen (HLA)-immunized patients. Other forms of plasma purification have been reported to reduce the level of fibrinogen, which affects the blood properties. In this study we investigated the effects of IA therapy using both adsorbents on plasma fibrinogen and immunoglobulins G and M in 13 patients (8 patients were treated with TR-350, and 5 patients were treated with PH-350). During each session 1 plasma volume (2.8 ± 0.4 L of plasma) was processed through the immunocolumn and then returned to the patient together with the blood cells. Compared with the pretreatment values, the plasma fibrinogen, IgG, and IgM concentrations were significantly reduced after IA therapy (p < 0.01 for TR-350; p < 0.04 for PH-350). There was a positive correlation between the degree of reduction of plasma proteins and the number of IA treatments given. A nonpara-metric test (Wilcoxon's signed-rank test or the Mann-Whitney test) was used for statistical analysis. We conclude from our study that IA therapy effectively lowers the plasma levels of fibrinogen, IgG, and IgM and thus can be considered a valuable alternative to other blood purification methods.