复合海绵及载药复合海绵止血性能研究

目的 评价复合海绵及其载药后对兔肝、脾创面的局部止血性能.方法 采用复合交联、冷冻干燥得到复合海绵;将其浸入一定浓度的氨甲环酸中,冻干得载药复合海绵.在兔肝、脾损伤创面,分别敷用复合海绵和载药复合海绵,观察正常情况下和肝素抗凝后兔肝、脾创面的出血时间及出血量,并与可吸收性明胶海绵和壳聚糖海绵比较.结果 正常情况下,复合海绵的止血时间和出血量较明胶海绵组和壳聚糖海绵组缩短或减少(P＜0.05,0.01);在肝素抗凝后,明胶海绵止血时间明显延长,而壳聚糖海绵和复合海绵的变化并不明显.载药复合海绵与复合海绵相比,在正常状态下止血性能有明显提高,但在凝血功能障碍时止血性能没有显著变化,且止血性能与载药量不呈线性关系.结论 复合海绵和载氨甲环酸复合海绵较明胶海绵止血性能明显提高,尤其是在凝血功能障碍时.

Abstract：

Objective To evaluate the hemostatic efficacy of complex sponge and drug-loaded complex sponge on hepatic and splenic wounds in rabbits. Methods Complex sponge was prepared by means of cross-linking and lyophilization. Then, the sponge was immersed into the tranexamic acid solution and lyophilized to obtain the drug-loaded sponge. The complex sponge and drug-loaded complex sponge were respectively used on the hepatic and splenic wounds of rabbits to observe the bleeding time and blood loss under normal and liquemine anticoagulation respectively. The gelatin sponge and the chitosan sponge were used as controls. Results Under normal condition, the hemostatic time and blood loss of the complex sponge was decreased obviously compared with the gelatin sponge ( P＜ 0. 01 ) and compared with the chitosan sponge ( P ＜ 0. 05 ). Posterior to liquemine anticoagulation, the hemostatic time was increased obviously in the gelatin sponge but showed no difference for the chitosan sponge and the complex sponge. Compared with complex sponge, the hemostatic efficacy of the tranexamic acid-loaded complex sponge was improved markedly for normal rabbits. While the hemostatic efficacy showed no significant change for rabbits with coagulation disorders, when there was no linear relationship between the hemostatic efficacy and the content of tranexamic acid. Conclusions The hemostatic efficacy of the complex sponge and the drug-loaded complex sponge surpass obviously that of the gelatin sponge, especially for the rabbits with coagulation disorders.     

复合海绵的细胞毒性及生物相容性研究

目的评价复合海绵的细胞毒性及生物相容性。方法采用MTT实验考察复合海绵浸提液对L929细胞增殖的抑制作用;扫描电镜观察L929细胞在海绵表面的生长情况;利用分光光度法测定其对鼠抗凝血的溶血作用;在鼠肝脏造成活性出血创面,用复合海绵或明胶海绵止血后,光镜观察海绵与肝脏组织的相容性。结果复合海绵浸提液对L929细胞增殖无抑制作用,该细胞可在海绵表面正常生长;无溶血作用,组织相容性较好。结论复合海绵无细胞毒性,且具有良好的生物相容性。     

内毒素休克大鼠线粒体质子跨膜转运的改变

内毒素休克大鼠线粒体质子跨膜转运的改变重庆第三军医大学野战外科研究所第二研究室（重庆４０００４２）杨鹤鸣陆松敏刘建仓李萍朱正坤郭素清跨线粒体内膜质子电化学梯度（△ｕＨ＋）是ＡＴＰ合成的动力，质子跨膜转运是△ｕＨ＋形成的基础。本实验用荧光探针（ＡＣＭＡ...     

紫芪方对缺氧复氧所致大鼠小肠上皮细胞损伤的保护作用

目的观察缺氧复氧对大鼠小肠上皮细胞（intestinal epithelial cell，IEC）-6培养液中超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量及细胞内Ca^2＋浓度和线粒体膜电位的影响，探讨复方中药-紫芪方对IEC-6肠上皮细胞缺氧复氧损伤的保护作用及机制。方法复制IEC-6细胞缺氧复氧损伤模型，采用紫外分光法测定缺氧复氧后及紫芪方血清治疗后细胞培养液中SOD活性及MDA含量；采用激光共聚焦显微镜测定细胞Ca^2＋浓度和线粒体膜电位变化。结果细胞缺氧复氧损伤后，可导致细胞培养液中SOD活性显著降低、MDA含量显著升高、线粒体膜电位明显降低及细胞内Ca^2＋浓度明显升高（P〈0．01）。紫芪方药物血清治疗后，可提高细胞培养液中SOD活性并降低其MDA含量，同时稳定了线粒体膜电位并降低细胞内Ca^2＋浓度（P〈0．05）。结论缺氧复氧可导致IEC-6肠上皮细胞损伤；紫芪方血清对IEC-6小肠上皮细胞缺氧复氧损伤具有显著的保护作用。     

Gene damages of mitochondrial DNA encoding cytochrome oxidase of intestinal epithelial cells in hemorrhagic shock rats

Objective: To investigate the detrimental effects of hemorrhagic shock on the structure and function of mitochondria DNA (mtDNA) encoding cytochrome oxidase genes in intestinal epithelial cells. Methods: Wistar rats were used and divided into two groups: hemorrhagic shock group and control group. Hemorrhagic shock model of rats was utilized in this experiment. The mtDNA was extracted from the intestinal epithelial cells and amplified by polymerase chain reaction (PCR) with different primers of cytochrome oxidase (COX I, COX II and COX III). The products of PCR were directly sequenced. Results: Hemorrhagic shock could result in the point mutagenesis in mitochondrial genome encoding cytochrome oxidase (COX I and COX II). There were 4, 4, 22, 16, 35 point mutations in COX I from 5545 to 6838 bp in 5 shocked rats. There were five point mutations in COX II from 7191 to 7542 bp at the site of t7191c, t7212c, a7386g, a7483g, c7542g in 1 shocked rat. There was no mutation found in COX III. Conclusions: Hemorrhagic shock could significantly induce the damage of the gene of cytochrome oxidase encoded by mtDNA.     

参芨阻克方对失血性休克大鼠肠粘膜上皮细胞线粒体细胞色素和能荷的影响

目的　研究参芨阻克方 (简称参芨 )对失血性休克大鼠小肠粘膜上皮细胞线粒体功能的影响。方法　采用Wigger’s法建立失血性休克动物模型 ,分离小肠粘膜上皮细胞线粒体 ,检测细胞色素aa3、b、c、c1 和能荷的水平。结果　失血性休克后小肠粘膜上皮细胞线粒体细胞色素aa3、b、c、c1 和能荷均显著降低 ;而参芨治疗组小肠粘膜上皮细胞线粒体细胞色素aa3、b、c、c1 和能荷均显著提高 (P <0 .0 5vs休克组 )。结论　失血性休克大鼠小肠粘膜上皮细胞线粒体呼吸链电子传递活性受到损伤 ,能量合成障碍 ,而参芨能显著改善线粒体的呼吸功能。     

Changes of proton transportation across the innner mitochondrial membrane and H＋^-ATPase in endotoxic shock rats

To investigate the changes of protontransportation across the inner mitochondriai membrane(IMM) and H^ -ATPase of hepatocytes in endotoxic shockrats.     

失血性休克时肠上皮细胞线粒体形态与功能变化研究

目的：定量分析大鼠失血性休克肠上皮细胞线粒体形态与功能的改变，探讨失血性休克缺血缺氧时肠上皮细胞线粒体结构和功能的改变。方法：Wistar大鼠随机分为对照组、失血性休克2h和5h组，采用电镜观察、生物体视学测量线粒体形态，用Clark氧电极测线粒体呼吸功能。结果：失血性休克2h组线粒体平均截面周长、长径、平均直径及其面密度、体密度分别较对照组增加24％、27％、25％、26％、44％，失血性休克5h组则分别较对照组增加45％、45％、45％、47％、122％。休克5h组与对照组比较，平均截面积增加100％，比表面和数密度分别下降32％、24％，嵴和基质破坏明显。休克2h线粒体呼吸控制率(RCR)已下降，休克5h组线粒体呼吸控制率与对照组比较减少26．9％。P／O值三组无改变。结论：失血性休克时大鼠肠上皮细胞线粒体形态发生显著改变：表现为肿胀，嵴和基质破坏，数量减少。RCR值失血性休克2h开始降低。P／O值变化不明显。     

失血性休克大鼠肠上皮细胞线粒体DNA COX Ⅰ基因突变与其编码蛋白质结构功能关系的研究

目的 探讨失血性休克缺血缺氧导致线粒体DNA（mtDNA）编码细胞色素C氧化酶（COX）基因损伤（突变）对其编码蛋白结构与功能的影响及两者之间的关系。方法 采用生物信息学技术,运用计算机同源模建的方法模拟牛天然COX亚单位和要研究的突变体的空间结构,并利用已有的实验数据,结合模建的结果进行了结构、功能的分析、研究。结果 COX Ⅰ突变区30-32肽段吻合程度比其它肽段降低,使COX Ⅰ的三维结构发生了改变;同时COXⅠ突变位点是残基101Arg突变成Leu,和362Val突变为侧链体积较大的Met,使突变部位附近残基的侧链结构环境发生了极大的变化,导致附近的电荷性质、亲疏水性质和空间特性出现变化,这导致COX全酶三维结构的稳定性下降和整个酶复合物的形成受到了影响。结论 失血性休克缺血缺氧导致mtDNA编码COX基因损伤（突变）后使其编码的COX蛋白空间结构发生改变,这种改变是其功能改变（如酶蛋白活性下降）的主要原因。     

生物止血海绵的安全性评价

目的 评价一种自制止血海绵作为医用生物材料的安全性.方法通过体内埋植法和体外酶降解法考查其降解作用;采用MTT法评价其对鼠成纤维细胞L929的细胞毒性;采用腹腔注射法观察其全身急性毒性;采用皮肤刺激、皮内刺激、眼刺激法考察其刺激作用.结果该止血海绵具有一定的降解性,无细胞毒性和急性毒性,无刺激性.结论实验结果提示该止血海绵是一种安全的,具有潜在临床应用价值的生物医用材料.