应用经胸超声心动图评估快速左心耳起搏心房颤动模型心脏结构及功能的变化

目的:应用经胸超声心动图观察高频率左心耳起搏致猪慢性心房颤动模型心脏结构和功能的变化。方法:实验于2005-09/2006-08在南京医科大学第一附属医院江苏省实验动物中心完成。①12只苏钟种猪随机分为实验组及对照组各6只,所有动物均开胸,将起搏电极固定在左心耳根部,高频率脉冲发生器植入左侧胸部囊袋。实验组术后恢复1周后起搏器以500次/min的频率快速起搏左心耳8周;对照组始终不起搏。②术后心电图定期监测起搏、心房颤动的发生情况;于术前、起搏后1周、起搏后4,8周超声心动图观察实验动物左房内径、心室收缩及舒张末左房面积、左房和左室射血分数、左室舒张及收缩末内径、左心室短轴缩短率等变化。结果:①实验组5只完成了实验,术后2周复查心电图,1只动物发生房颤,起搏8周3只发生阵发性房颤,1只未发生房颤;对照组则未发生任何心律失常情况。②左心房相关指标:起搏后1周,实验组左房内径、收缩末期左心房面积和舒张末期左房容积均较起搏前增加[(2.70±0.12),(2.50±0.12)cm;(6.78±0.81),(6.21±0.93)cm2;(4.66±0.53),(3.78±0.57)mL;P均<0.05],左房射血分数较起搏前下降[(55.6±6.0)%,(63.8±4.0)%,P<0.01],至起搏4,8周,左房射血分数进一步降低,左房内径等指标则继续增大。③左心室相关指标:起搏后1周,实验组左室舒张、收缩末期内径较起搏前增加[(3.64±0.13),(3.46±0.15)cm;(2.48±0.08),(2.14±0.09)cm;P均<0.01],左心室短轴缩短率和左室射血分数较起搏前下降[(31.6±2.0)%,(37.8±3.0)%;(60.8±2.0)%,(69.2±4.0)%;P均<0.01];至起搏4,8周,左心室短轴缩短率和射血分数进一步降低,左室舒张、收缩末期内径则继续增大,与对照组比较也差异显著(P<0.05,0.001)。结论:①超声心动图是监测房颤模型建立过程中心房、心室结构和功能变化的有效手段。②高频起搏左心耳是建立猪心房颤动模型的有效方法,快速心房起搏可导致左心房左心室增大及心功能减退。     

自主研制镍钛记忆合金左心耳封堵器封闭左心耳对实验动物左心功能的影响

目的:应用经胸彩色多普勒超声技术评价自主研制的镍钛记忆合金左心耳封堵器封闭左心耳对实验动物猪左心房、左心室功能的影响。方法:实验于2005-09/2006-08在南京医科大学第一附属医院江苏省实验动物中心完成。①实验分组:选用苏钟小型种猪17只,随机分为实验组12只和对照组5只。②实验干预:实验组12只苏钟小型种猪使用自主研制的左心耳封堵器(发明专利号码:200610037789.3,公开号CN1799521,由镍钛合金骨架、多聚四氟乙烯膜和传送连接部分等构成。其外观呈单盘状,封堵器的左心房面呈圆盘状,直接连接放入心耳内的圆柱体结构)行左心耳封堵,对照组5只手术步骤相同而不采用封堵器行左心耳封堵。③实验评估:两组动物分别于术前、术后1周、2周、4周采用经胸超声心动图检查观察心功能的改变,测量左心房内径、最大及最小容积、左房射血分数、左心房搏出量、血流分数等左房功能参数以及左室射血分数、左室短轴缩短率、Tei指数、E/A比值等指标。结果:①实验动物数量分析:在施行左心耳封堵后,1头猪于术中出血过多并出现室颤后死亡,1头猪因封堵器脱入左房,卡在二尖瓣口导致死亡。其余动物封堵效果良好。②两组动物术后1,2,4周左房功能指标各参数与术前比较无明显变化(P>0.05);与术前相比,实验组术后1周、2周左室射血分数、左心室短轴缩短率、E/A比值分别由术前的0.70±0.04、0.39±0.03、1.33±0.28降低至术后1周的0.59±0.05、0.31±0.03、0.95±0.11(P<均0.01)及术后2周的0.62±0.05、0.33±0.05、0.90±0.05(P<均0.01);Tei指数由术前的0.48±0.02增加至术后1周的0.59±0.03(P<0.01)及术后2周的0.58±0.04(P<0.01)。对照组手术前后左室功能指标差异无显著性。结论:自主研制左心耳封堵器可以有效的封堵左心耳;左心耳封堵后短期内对实验动物左房功能无明显影响;封堵后短期内对左心室功能具有短期的减弱,更长期的安全性有待于进一步研究。     

油酸多相脂质体(139)注射液包封率测定方法的研究

本文提出了油酸多相脂质体139注射液中脂质体的药物包封率和药物含量的测定方法,以凝胶过滤法Sephadex G-50柱测定139注射液中多相脂质体的重量包封率Qw平均为94.2%;同时又以显微镜照像及统计方法测量了脂质体的体积包封率Qv平均为97.1%。并讨论了影响脂质体中药物包封率的各种因素。     

高效液相色谱法同时测定盐酸维拉帕米及其主要代谢产物

建立了反相高效液相色谱法同时测定人血浆中维拉帕米及其主要代谢产物去甲维拉帕米血药浓度.以甲醇—水—三乙胺(67∶33∶0.4,pH6.7)为流动相,乙吗噻嗪(ethmosine)为内标,样品用正己烷—正丁醇混合液提取浓缩后进样,紫外检测器检测(279nm)。此法操作简便,精密度好,日内、日间误差:维拉帕米<8.6%,去甲维拉帕米<7.6%;方法回收率高,维拉帕米、去甲维拉帕米回收率均>92%。两者血药浓度在25～1000ng·ml-1范围内呈线性关系,最小检测浓度维拉帕米:2.5ng·ml^-1,去甲维拉帕米:5.0ng·ml^-1。应用该法测定了6名志愿者口服盐酸维拉帕米片剂后的血药浓度。     

氯霉素控释眼丸的研究

氯霉素控释眼丸(以下简称眼丸)经体外、眼内试验可持续恒速释药10d,眼内释药量平均为13.35μg/h。眼丸是根据中药“龙虱子”设计,用滴丸工艺制成,于中央钻孔以达到恒速释药。制法简便、成本低、使用方便、安全、疗效可靠。     

肝细胞生长因子拮抗剂NK4抑制肿瘤的机制

0 引言 肝细胞生长因子(hepatocyte growth factor,HGF)是由间质细胞产生的细胞因子,作用于肿瘤细胞表面的跨膜受体c-Met蛋白,引起肿瘤细胞的浸润、转移,而且HGF对新生血管的生成起促进作用.1997年Date等[1]用胰弹性蛋白酶对重组人HGF进行消化裂解,发现了一种新的全面拮抗HGF生物活性功能的拮抗剂-NK4.     

Improvement of irradiation-induced fibroblast damage by α2-macroglobulin through alleviating mitochondrial dysfunction

Contextα2-Macroglobulin (α2-M) is believed to be a potential anti-irradiation agent, but related mechanisms remains unclear.ObjectiveWe investigated the irradiation protective effect of α2-M.Materials and methodsA total of 10 Gy dose of irradiation was used to damage human skin fibroblasts. The influence of α2-M (100 µg/mL) on the proliferation, migration, invasion and apoptosis of fibroblasts was observed using Cell Counting Kit-8 (CCK8), wound healing, transwell, and flow cytometry. Malondialdehyde, superoxide dismutase and catalase was measured using related ELISA kits. The levels of mitochondrial membrane potential and calcium were detected using flow cytometry. The expression of transient receptor potential melastatin 2 (TRPM2) was investigated through western blotting and immunofluorescence staining.ResultsHigh purity of α2-M was isolated from Cohn fraction IV. α2-M significantly increased cell proliferation, migration, invasion, but suppressed cell apoptosis after irradiation. The promotion of cell proliferation, migration and invasion by α2-M exceeded over 50% compared group irradiation. The increased cell ratio in the S phase and decreased cell ratio in the G2 phase induced by irradiation were remarkably reversed by α2-M. α2-M markedly suppressed the increased oxidative stress level caused by irradiation. The mitochondrial damage induced by irradiation was improved by α2-M through inhibiting mitochondrial membrane potential loss, calcium and TRPM2 expression.Discussion and conclusionsα2-M significantly promoted the decreased fibroblast viability and improved the mitochondria dysfunction caused by irradiation. α2-M might present anti-radiation effect through alleviating mitochondrial dysfunction caused by irradiation. This study could provide a novel understanding about the improvement of α2-M on irradiation-induced injury.