Fibulin-5在醛固酮腺瘤模型大鼠主动脉中的表达

目的 观察醛固酮对主动脉Fibulin-5表达的影响.方法 将32只SD大鼠随机分为4组,每组8只:(1)空白溶剂设为对照(60%丙二醇+10%乙醇+30%双蒸水);(2)醛固酮腺瘤:泵入醛固酮(1 μg/h);(3)醛固酮腺瘤+特异性盐皮质激素受体阻断剂:依普利酮[100 mg/(kg·d)];(4)醛固酮腺瘤+血管扩张剂:肼苯哒嗪[25 mg/(kg·d)].渗透泵内分别注入醛固酮或空白溶剂,然后将其埋植于大鼠背部皮下.8周后,免疫组织化学和免疫印迹法检测主动脉Fibulin-5的表达.结果 与对照组大鼠比较,腺瘤组大鼠主动脉Fibulin-5的表达显著增加(P＜0.05);与肼苯哒嗪不同,依普利酮可以抑制醛固酮的上述作用(P＜0.05).结论 醛固酮可以直接诱导主动脉Fibulin-5 表达增加,后者在醛固酮增多引起的主动脉重构过程中可能发挥重要作用.     

Fibulin-5在醛固酮腺瘤模型大鼠主动脉中的表达

目的 观察醛固酮对主动脉Fibulin-5表达的影响.方法 将32只SD大鼠随机分为4组,每组8只:(1)空白溶剂设为对照(60%丙二醇+10%乙醇+30%双蒸水);(2)醛固酮腺瘤:泵入醛固酮(1 μg/h);(3)醛固酮腺瘤+特异性盐皮质激素受体阻断剂:依普利酮[100 mg/(kg·d)];(4)醛固酮腺瘤+血管扩张剂:肼苯哒嗪[25 mg/(kg·d)].渗透泵内分别注入醛固酮或空白溶剂,然后将其埋植于大鼠背部皮下.8周后,免疫组织化学和免疫印迹法检测主动脉Fibulin-5的表达.结果 与对照组大鼠比较,腺瘤组大鼠主动脉Fibulin-5的表达显著增加(P＜0.05);与肼苯哒嗪不同,依普利酮可以抑制醛固酮的上述作用(P＜0.05).结论 醛固酮可以直接诱导主动脉Fibulin-5 表达增加,后者在醛固酮增多引起的主动脉重构过程中可能发挥重要作用.     

鼠双微体-2基因在醛固酮增多症大鼠模型主动脉平滑肌中的表达

目的 观察醛固酮对大鼠主动脉平滑肌鼠双微体-2基因(MDM2)表达的影响.方法 将SD大鼠随机分为3组,每组8只.采用皮下给药的方法建立醛固酮增多症模型,其中醛固酮组经微量渗透泵持续释放醛崮酮(1μg/h);醛同酮+螺内酯组除给予等量醛固酮外,每日行螺内酯灌胃(每日100mg/kg);对照组仅泵空白溶剂.尾套法检测大鼠血压,4周后处死所有大鼠,测定血钾、钠、醛固酮浓度及血浆肾素活性.分别采用逆转录.聚合酶链反应(RT-PCR)、Westerill blot、免疫组织化学检测主动脉平滑肌MDM2基因表达.结果 (1)成功建立醛同酮增多症大鼠模型:醛固酮组2周后血压明显升高,血钾下降,呈现低肾素、高醛固酮特征,与对照组比较差异有统计学意义(P<0.01);(2)醛固酮组主动脉平滑肌MDM2基因表达明显高于对照组(P<0.01).螺内酯可抑制醛固酮的上述作用(P<0.01).结论 醛固酮可促进血管平滑肌细胞中MDM2的表达,而螺内酯可拮抗其效应.     

Fibulin-5在醛固酮腺瘤模型大鼠主动脉中的表达

目的 观察醛固酮对主动脉Fibulin-5表达的影响.方法 将32只SD大鼠随机分为4组,每组8只:(1)空白溶剂设为对照(60%丙二醇+10%乙醇+30%双蒸水);(2)醛固酮腺瘤:泵入醛固酮(1 μg/h);(3)醛固酮腺瘤+特异性盐皮质激素受体阻断剂:依普利酮[100 mg/(kg·d)];(4)醛固酮腺瘤+血管扩张剂:肼苯哒嗪[25 mg/(kg·d)].渗透泵内分别注入醛固酮或空白溶剂,然后将其埋植于大鼠背部皮下.8周后,免疫组织化学和免疫印迹法检测主动脉Fibulin-5的表达.结果 与对照组大鼠比较,腺瘤组大鼠主动脉Fibulin-5的表达显著增加(P＜0.05);与肼苯哒嗪不同,依普利酮可以抑制醛固酮的上述作用(P＜0.05).结论 醛固酮可以直接诱导主动脉Fibulin-5 表达增加,后者在醛固酮增多引起的主动脉重构过程中可能发挥重要作用.

Abstract：

Objective To observe the effect of aldosterone on fibulin-5 expression in the aorta.Methods Thirty-two male rats were randomly divided into 4 groups;vehicle (control) ,aldosterone-producing adenoma, aldosterone-producing adenoma plus eplerenone or hydralazine. They were then implanted with an osmotic mini-pump that infused either aldosterone or the vehicle. After 8 weeks, Fibulin-5 was examined by immnuohistochemistry and Western blotting. Results Compared with controls, the model rats with aldosterone-producing ademoma exhibited elevated aortic expression of Fibulin-5. This effect of aldosterone was significantly suppressed after co-treatment with eplerenone but not with hydralazine. Conclusion It suggest that aldosterone directly promotes aortic expression of Fibulin-5 that may play an important role in aldosterone-induced aortic remodeling.     

Bcl—2在醛固酮腺瘤模型大鼠主动脉中的表达

目的：观察醛固酮对主动脉Bcl-2表达的影响。方法：32只SD大鼠随机均分为4组：①空白溶刹口为对照（60％丙二醇＋10％乙醇＋30％双蒸水）;②醛固酮腺瘤：泵入醛固酮（1／,g／h）;③醛固酮腺瘤＋依普利目组：依普利酮（100mg·kg-1·d-1）;④醛固酮腺瘤＋肼苯哒嗪组：肼苯哒嗪（25mg·kg-1·d-1）。渗透泵内分别注入醛固酮或空白溶剂,然后将其埋植于大鼠背部皮下。8周后,免疫组织化学和免疫印迹检测主动脉Bcl的表达。结果：与对照组相比,腺瘤组大鼠主动脉Bcl—2表达显著减少（P〈0．05）;依普利酮能够拮抗醛同酮对Bcl—2表达的抑制作用（P〈20．05）。结论：醛固酮通过抑制Bcl—2表达,调节细胞凋亡状态,可能足醛固酮诱导主动脉重构的机制之一。     

半胱氨酸蛋白酶32在丝裂霉素C诱导膀胱癌细胞凋亡中的作用

目的　探讨半胱氨酸蛋白酶 32 (caspase 3)在丝裂霉素C(MMC)诱导膀胱癌EJ细胞凋亡中的作用。　方法　采用末端脱氧核苷酸转移酶介导生物素标记法 (TUNEL)和流式细胞术 (FCM)研究EJ细胞凋亡及细胞周期变化 ,分析caspase 3抗体对低剂量MMC诱导EJ细胞凋亡的影响。　结果　TUNEL法显示MMC组EJ细胞出现细胞凋亡特有的形态学特征 ,凋亡指数 (6 2 .9± 2 .2 ) % ,较cas pase 3抗体加MMC组 (4.9± 0 .3) %和空白组 (2 .7± 0 .7) %显著增高 (P <0 .0 0 1)。FCM检测结果明 ,MMC主要诱导G0 /G1期细胞凋亡而出现凋亡峰 ,凋亡率 2 6 .0 6 % ;caspase 3抗体能特异性抑制MMC诱导EJ细胞凋亡 ,凋亡率仅为 4.6 5 %。　结论　低剂量MMC对caspase 3的活化在诱导膀胱癌细胞凋亡中有重要作用。     

小豆蔻明对迟发性脑血管痉挛的作用

目的 探讨小豆蔻明对蛛网膜下腔出血迟发性脑血管痉挛(DCVS)的作用机制.方法 颈内动脉刺破法制作大鼠蛛网膜下腔出血迟发性脑血管痉挛模型,在造模后第1～7天,每天给予小豆蔻明(7.5 mg/kg)腹腔注射,对照组注入等量生理盐水.Image pro-plus软件测量苏木素-伊红(HE)染色大鼠基底动脉管壁厚度,免疫组织化学法检测磷酸化蛋白激酶B (p-Akt),免疫荧光染色检测Akt通路下游增殖蛋白C-myc表达和α-平滑肌肌动蛋白(α-SMA)改变.原位缺口末端标记法(TUNEL)检测细胞凋亡情况.结果 药物治疗组p-Akt、C-myc表达(2.36±0.58、0.96±0.20)、内皮细胞和平滑肌细胞凋亡[(2.77 ±0.29)％]明显低于出血组[5.58±0.65、2.56±0.34、(5.45±0.56)％]和溶媒组大鼠[5.41±0.55、2.67±0.56、(5.53±0.40)％,P＜0.05],而α-SMA表达量(0.23±0.02)高于出血组(0.14±0.02)和溶媒组(0.15 ±0.02,P ＜0.05).结论 小豆蔻明可能通过抑制Akt通路下调C-myc表达,并促进α-SMA表达而影响平滑肌表型转换和增殖,同时能减少内皮细胞和平滑肌细胞凋亡,从而缓解蛛网膜下腔出血所致DCVS.     

人参皂甙Rb1减轻大鼠脊髓缺血再灌注损伤的实验研究

目的在整体水平探讨人参皂甙Rb1对脊髓缺血再灌注损伤(spinal cord ischemiareperfusion injury,SCII)的治疗作用。方法 Sprague-Dawley(SD)大鼠72只,随机分为假手术组、对照组(SCII+安慰剂)和实验组(SCII+人参皂甙Rb1),采用腹主动脉夹闭法建立SCII模型。应用Basso-Beattie-Bresnahan(BBB)评分系统评价神经功能,HE染色观察病理组织结构和细胞形态改变,原位末端脱氧核苷酸转移酶标记(the in situ terminal deoxynucleotidyl transferase-mediateddUTP nick end-labeling technique,TUNEL)方法检测细胞凋亡情况。结果人参皂甙Rb1干预可以减轻脊髓缺血再灌注损伤导致的后肢功能障碍。HE染色显示人参皂甙Rb1干预可减轻神经元受损程度。TUNEL检测显示假手术组很少有细胞凋亡,对照组的神经细胞凋亡率最高,实验组与对照组比较可显著减少细胞凋亡率,差异有统计学意义(P<0.05)。结论人参皂甙Rb1可改善大鼠神经功能,减轻SCII导致的神经元受损,减少脊髓细胞凋亡。     

紫杉醇抑制大鼠移植动脉硬化的作用

目的 探讨紫杉醇防治大鼠移植动脉硬化的作用及其机制.方法 采用大鼠胸腹主动脉移植模型,同系移植组供、受者均为Wistar大鼠,同种移植组和紫杉醇治疗组的供者均为Wistar大鼠,受者均为SD大鼠,紫杉醇治疗组术后第1～14天腹腔注射紫杉醇2 mg·kg-1·d-1,其它组则每日腹腔注射相同体积的生理盐水.术后30 d取出移植动脉,光镜下观察移植动脉的内膜增生情况,同时采用电镜和末端脱氧核苷酸转移酶介导的三磷酸脱氧尿嘧啶缺口末端标记法(TUNEL)检测血管平滑肌细胞(VSMCs)凋亡情况.结果 术后30 d,同系移植组血管形态基本保持正常;同种移植组血管内膜明显增厚,内外膜有大量炎症细胞浸润,管腔显著狭窄;紫杉醇治疗组移植血管内膜无明显增厚,内外膜炎症细胞浸润较同种移植组明显减轻,管腔无狭窄.电镜及TUNEL检测结果显示紫杉醇治疗组VSMCs凋亡较其它两组明显增高.结论 紫杉醇能明显抑制移植动脉的硬化,其作用机理可能与其诱导移植动脉VSMCs凋亡有关.     

灯盏细辛对大鼠肾冷缺血再灌注损伤中细胞凋亡的影响

目的 观察中药灯盏细辛对大鼠肾脏冷缺血再灌注损伤(IRI)中肾脏细胞凋亡及相关基因表达的影响.方法 封闭群SD大鼠36只,随机分为3组,每组12只.假手术组(A组),对照组(B组),实验组(C组).药物应用:C组术前15 min,灯盏细辛注射液按1.2 ml/100 g通过尾静脉注射,A、B组按相应剂量注射生理盐水.动物手术:A组,切除右肾.B、C组采用的是冷IRI模型,3组大鼠均在术后24h再次手术切除左肾进行检测.透射电镜检查肾组织形态学,免疫组织化学检测凋亡相关的基因bcl-2与bax的表达,原位末端标记法(TUNEL)检测细胞凋亡.结果 (1)超微结构检查(透射电镜):A组结构正常;B组细胞呈损伤形态:线粒体肿胀,微绒毛减少,胞质内空泡形成,部分细胞核可见凋亡迹象.C组病变较B组显著减轻.(2)免疫组织化学蛋白阳性染色指数(PI):缺血再灌注后B、C组的bcl-2表达分别为(21.21±1.18)％和(35.52±1.94)％,较A组(4.95±0.77)％均增多(P＜0.05),B组低于C组(P＜0.05).B、C组的bax表达分别为(58.55±2.90)％和(45.90±3.14)％,较A组(4.67±0.67)％增多(P＜0.05),而且B组高于C组(P＜0.05).A组的蛋白阳性染色指数的比值bcl-2/bax为(1.06±0.07)高于B组(0.35±0.03)和C组(0.78±0.07,P＜0.05),而且C组高于B组(P＜0.05).(3)细胞凋亡检测(TUNEL):细胞凋亡指数B组(28.57±3.58)％和C组(19.99±3.37)％均显著大于A组(2.33±0.42)％(P＜0.01),C 组小于B组(P＜0.01).结论 灯盏细辛减少大鼠肾脏冷IRI诱导的肾脏细胞的凋亡,与调节凋亡相关基因bcl-2与bax表达有关.     

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.