体外器官培养法评价四种高分子材料毒性

本文应用玻璃管架法培养鸡胚股骨的体外器官培养法评价了指关节、Ⅴ型节育环、男性依赖性假体修复件和宫颈帽四种硅橡胶材料,并进行了组织学观察和电镜的超微结构变化检查。结果显示:组织学观察,阴性对照毒性分级为0级,阳极对照毒性分级Ⅳ级,男性依赖性假体修复件硅橡胶的毒性分级为Ⅱ级,余为Ⅰ级。超微结构电镜观察,阴性对照软骨细胞呈双核,核大,核膜完整,胞浆中的内质网丰富,有少量空泡。阳性对照细胞明显变性,胞膜破裂,细胞器溶解,部分核膜破裂,核内有空泡变性。男性依赖性假体修复件硅橡胶所致细胞浆内部分区域细胞器结构不清楚,粗面内质网数目较少,显示了轻微的毒性反应,其它三种材料未见异常,四种材料中以男性依赖性假体修复件材料对组织器官的影响较为明显,但均属轻度毒性反应。     

生物材料血液相容性体外评价的研究进展

体外实验因其快捷、方便、特点 ,通常被用作生物材料血液相容性评价的初步筛选实验。在体外血液相容性评价中 ,需选用合理的血液与材料接触模型、敏感而又特异的检测指标 ,在整个实验中尽量避免外界非待测材料对血液的激活作用。另外接触时间、接触方式、切变率以及参照材料的选择等均是重要的影响因素。近年来 ,体外评价方法虽已取得很大进展 ,但仍有待于标准化 ,以更有效地评价生物材料的血液相容性。     

一种新型可显影栓塞剂的体外模拟研究

以合成的含碘聚合物溶于适宜的溶剂作为栓塞剂,建立体外输送模型和体外栓塞效能模型,观察研究可显影栓塞剂的体外模拟栓塞情况。观察栓塞剂在微导管中的输送情况,筛选出栓塞剂的适宜浓度;观察栓塞剂在体外栓塞效能模型中的栓塞过程,考查栓塞剂的弥散性、栓塞效果等,摸索推注速度及结束点等操作条件,验证栓塞剂的栓塞效能;通过两个模型的实验结果,筛选出了最佳栓塞剂浓度,最佳推注速度和结束点,为下一步做动物实验和临床试验提供了依据。     

一种新型重组抗体导向溶栓剂的体外溶栓研究

目的：探讨一种新型重组融合基因抗体导向溶栓剂ＳＺ５１Ｈｕ－ｓｅｕＰＡ的体外溶栓效力。方法：通过转并扩大生产获得的大量基因重组融合基因ＳＺ５１ＨｕｓｅｕＰＡ,通过抗体竞争结合实验确定融合蛋白抗体亲和力,进而与尿激酶进行不同浓度血小板血浆凝块体外溶栓比较。结果：该融合蛋白体外纤溶活性为３９０００Ｕ／ｍｇ;其抗体亲和力是鼠源性单抗的６７％。体外溶栓效力较ＵＰＡ提高４．１～８．４倍。结论：体外溶栓结果证明     

体外诊断试剂稳定性评价要求及常见问题

稳定性评价是体外诊断试剂产品性能验证的重要组成部分,一般包括实时稳定性、使用稳定性、运输稳定性等,是贯穿于整个试剂研发、上市前评价及上市后监测的重要内容,是产品有效期设计的依据。本文旨在参照我国现行注册申报相关法规及文件要求基础上,结合相关审评经验,阐述体外诊断试剂稳定性评价研究及常见问题,为从事该类产品注册申报前性能研究的从业人员提供参考。     

一种用于人工肝的新型吸附解毒剂—甲壳糖

本研究以天然甲壳素为原料,通过简单的化学、物理处理,制得一种用于人工肝的吸附解毒剂。经毒理学试验。体外静态测试和两种模型动物实验表明:该吸附解毒剂具有良好的生物相容性和血液相容性,对结合型胆红素和芳杂环氨基酸有较强的吸附能力。在研究黄疸模型动物实验中,实验犬经该吸附解毒剂进行灌流抢救后,在未作复原手术情况下,均能存活下来,且活动正常,未发现不良后遗症及其它不良反应。     

一种新型干性生物瓣膜耐久性能体外测试及评价

随着生物技术的发展,近年来出现了通过覆盖钙结合位点的牛心包处理技术,并以此为瓣叶材料制备出干性生物瓣膜。由于干性生物瓣膜临床应用时间短,尚缺少长期耐久性数据。本研究采用体外加速方法,对一种干性生物瓣膜耐久性能进行测试及评价。选取23和32 mm这两个规格干性生物瓣膜进行体外耐久性能测试。通过瓣膜脉动流实验、瓣叶热力学分析和显微镜下胶原纤维观察,对其耐久性能进行评价。经过2亿次循环(模拟临床使用5年),干性生物瓣膜流体力学性能无明显变化,其中23 mm规格干性生物瓣膜平均跨瓣压差有所升高,但仍处于同规格生物瓣膜较低水平;32 mm规格干性生物瓣膜平均跨瓣压差几乎没有变化。有效瓣口面积基本一致,返流百分比无明显变化,说明干性生物瓣膜未发生明显的狭窄和返流,能量损失无明显变化,说明瓣膜的效能无明显降低。瓣叶材料的热力学变性温度由96.6℃降至91.2℃;在双光子共聚焦显微镜下观察,同样测试条件下亮度变暗,但胶原纤维形状未发生变化,仍是卷曲的立体结构,说明胶原纤维含量降低,化学键部分丢失,与热变性温度表现一致。干性生物瓣膜耐久性能实验后,微观结构发生一定变化,但仍具有良好的流体力学性能。     

新型壳聚糖对血浆胆红素和细胞因子吸附性能的体外筛选初步研究

目的观察各类新型吸附剂对重型肝炎患者血浆中的胆红素和细胞因子的吸附性能。方法第一步,收集第一组重型肝炎患者的血浆各3ml,以8种不同的吸附剂(1#～3#为致孔剂浓度分别为3%、1%、5%的壳聚糖,4#为胺基化壳聚糖,5#为苯乙烯/二乙烯苯聚合物,6#为后交连苯乙烯/二乙烯苯聚合物,7#为壳聚糖-苯乙烯/二乙烯苯聚合物,8#为壳聚糖-后交连苯乙烯/二乙烯苯聚合物)各1ml进行吸附,检测对胆红素的吸附能力,做吸附剂筛选实验和吸附实验。第二步,用以上筛选出吸附率较好的两种吸附剂各1ml对第二组患者血浆(各3ml)进行胆红素和细胞因子的吸附实验。结果第一步实验显示胺基壳聚糖(4#)和苯乙烯/二乙烯苯聚合物(5#)有较好的吸附效果,4#吸附剂对总胆红素(TBiL)、直接胆红素(DBiL)、间接胆红素(IBiL)的吸附率分别为50.5%±3.4%、57.0%±11.3%、39.0%±7.2%;5#分别为30.1%±2.5%、32.6%±3.0%、27.6%±2.9%。第二步实验显示4#胺基化壳聚糖吸附后血浆中TBiL、DBiL、IBiL、白细胞介素6(IL-6)和肿瘤坏死因子α(TNF-α)水平下降比5#明显,有统计学意义(P<0.001)。结论胺基化壳聚糖(4#)体外吸附重型肝炎患者血浆中胆红素、细胞因子效果有明显优势。     

生物材料体外评价方法研究进展

引言 在生物材料与人体体液、组织和器官的接触应用中，对材料进行生物学评价是至关重要的。生物学评价通常包括体外和体内两种测试途径。体外实验是将材料或其浸提液在体外环境下与细胞或组织接触，观察材料对细胞数量、形态及分化的影响。体内实验则是将材料直接与动物体接触，观察植入体周围组织反映的状况，这类实验模拟了人体生理环境，与材料的最终应用状况接近。目前，动物体内植入仍是生物材料安全性和有效性评价的主要手段。体内实验也有一定的缺点，如在体内环境中，     

左旋多巴和姜黄素共递送protocells纳米粒的制备及体外评价

目的制备共载左旋多巴和姜黄素protocells纳米粒并进行体外评价。方法以介孔二氧化硅为内核,脂质双分子层为外膜,制备共载左旋多巴和姜黄素protocells纳米粒。使用激光粒度分析仪和透射电子显微镜对所制备纳米粒的形貌、粒径、多分散系数(PDI)和Zeta电势进行表征;采用高效液相色谱法对所制备纳米粒的载药量和包封率进行测定;采用透析袋法对所制备纳米粒的体外释放特性进行考察;应用粒径、Zeta电势、载药量等指标对所制备纳米粒的室温贮存稳定性进行评价。结果制备的载左旋多巴和姜黄素protocells纳米粒粒径分布均一性好、粒子表面呈电负性、平均粒径为(210.9±2.8)nm、PDI为(0.201±0.011)。其中左旋多巴的载药量为(20.28±0.43)%、包封率为(10.14±0.22)%;姜黄素的载药量为(1.97±0.01)%、包封率为(98.32±0.01)%。体外释放结果表明该纳米粒48 h姜黄素累计释放率为59.2%,且可有效阻止左旋多巴的泄漏,降低其在循环系统中的暴露量。稳定性结果表明左旋多巴和姜黄素在protocells纳米粒中稳定性良好。结论载左旋多巴和姜黄素的protocells纳米粒制备工艺简单,具有良好的理化性质、稳定性及所预期的释放性能。     

In vitro assays for the evaluation of drug resistance in tumor cells

Oncologic diseases are among leading cause of mortality in developed countries. Despite significant progress, the use of standard cytotoxic chemotherapy has reached a therapeutical plateau. Currently, the process of selecting chemotherapy represents a trial and error method neglecting biological individuality of tumor and its bearer. The improvement of treatment results is expected from ex vivo drug sensitivity testing which may allow to choose the most effective drug for individual patient and to exclude agents to which the tumor cells exert resistance. New techniques and rapidly increasing knowledge about the molecular basis of malignant diseases provide important opportunities for the future of chemotherapy. This paper reviews current methods used to test the resistance of tumor cells to a panel of anticancer agents in vitro. In addition, we focused on the in vitro MTT assay which represents one of major technique for testing of tumor cell resistance to anticancer agents.     

In vitro assessment of the haemolytic potential of candidate drugs

Several chemicals cause haemolysis when administered to mammals by the intravenous route. From a regulatory point of view there are no recommended methods for assessing the haemolytic potential of candidate drugs. In our laboratory, we routinely investigate the reaction between human (or animal) whole blood and candidate drugs (or their vehicles or metabolites) and measure haemolysis by assaying haemoglobin in the supernatants. Here, we describe this method. This test is inexpensive and requires only few millilitres of whole blood.     

In vitro inhibition by mammal erythrocytes on erythropoiesis

Packed mammal erythrocytes of the same mass but characterised by different mean corpuscolar volumes (MCV) were incubated. The influence of these conditioned media (ECM) on⁵⁹Fe uptake into haem in cultures of guinea-pig bone-marrow cells was studied. The present results demonstrate that ram erythrocyte ECM (MCV = 28) caused a more marked in vitro depression of haeme synthesis than did calf (MCV = 34) and guinea pig (MCV = 69) erythrocyte ECM and that this inhibitory effect is correlated to the MCV of the erythrocytes considered.     

In vitro proliferation of pluripotent hematopoietic progenitors

Summary Different ratios of normal human plasma concentrations to fetal bovine serum concentrations have been tested on the in vitro proliferation of pluripotent hematopoietic progenitors. The slight modifications of the culture procedure described here resulted in significant enhancement of BFU-e formation whereas no significant differences in the formation of CFU-e, CFU-meg, CFU-gm, and CFU-mix were observed.     

In vitro testing of a novel blood pump designed for temporary extracorporeal support

Extracorporeal blood pumps are used as temporary ventricular assist devices or for extracorporeal membrane oxygenation. The ideal pump would be intrinsically self-regulating, carry no risk of cavitation or excessive inlet suction, be afterload insensitive, and valveless thus reducing thrombogenicity. Currently used technology, including roller, centrifugal, and pneumatic pulsatile pumps, does not meet these requirements. We studied a nonocclusive peristaltic pump (M-Pump) in two mock circulatory loops and compared the performance to a frequently used centrifugal pump and a modified prototype of the M-Pump (the BioVAD). The simple resistance loop consisted of the investigated pump, a fixed height reservoir at 150 mm Hg, and a variable inflow reservoir. The pulsatile circulation used a mock patient simulator with adjustable resistance elements connected to a pneumatic pulsatile pump. The M-Pump intrinsically regulated flow with changing preload, was afterload insensitive, and did not cavitate, unlike the centrifugal pump. The BioVAD also demonstrated these features and could augment output with the use of vacuum assistance. A nonocclusive peristaltic pump may be superior for short-term extracorporeal circulatory assist by mitigating risks of excessive inlet suction, afterload sensitivity, and thrombosis.     

纳米银溶胶的体外细胞毒性评价及其机制研究

目的 对纳米银溶胶的体外细胞毒性进行评价,初步探讨纳米银对细胞的毒性作用机制.方法利用化学还原法制备纳米银溶胶,通过紫外-可见分光光度计和透射电镜对其物理特性进行检测;以小鼠纤维肉瘤细胞( L929)为研究对象,通过细胞形态观察、LIVE/DEAD染色分析和MTT检测来评价纳米银对细胞的毒性作用;在电子显微镜下观察纳米...     

人子宫内膜蜕膜化间质细胞与囊胚体外共培养建立人胚胎着床模型

目的建立有效的体外人胚胎着床模型,为体外研究人胚胎着床过程提供条件。方法将人子宫内膜蜕膜化的间质细胞与囊胚共同培养,光镜下观察囊胚在细胞上的定位、粘附及侵入过程;免疫荧光法测定共同培养系统中的角蛋白,以确定着床模型的建立。结果与蜕膜细胞共培养5—10h后,囊胚开始黏附在细胞层上,48h后侵入蜕膜细胞间;共培养48h后,胚胎及周围的内膜细胞表达角蛋白阳性。结论囊胚与蜕膜化细胞共同培养,可以成功建立体外胚胎着床模型,更好地模拟体内着床时状态,是较理想的体外研究模型。     

In vitro priming of human lymphocytes to heterologous insulins

We have developed an in vitro priming assay in which peripheral blood lymphocytes from normal subjects are primed with insulin for 14 days prior to challenge with insulin in conjunction with autologous antigen-presenting cells for a further 5 days. Sheep, beef and pork insulins possess, respectively, four, three and one amino acid differences from the human molecule (out of a total of 51 residues) and the magnitude of the response to priming correlates with the degree of sequence variation. Although human insulin produces little response, priming with heterologous insulins readily induces auto-immunization on secondary challenge. The response to porcine priming was enhanced if the secondary cultures were challenged with bovine or ovine insulin, i.e., a heteroclitic response was observed.

Individual donors differ in their response to priming and high responders possess the HLA-DR7 glycoprotein more frequently than low responders. This is in keeping with previous studies on antibody production in vivo and probably relates to the case with which individual class II glycoproteins complex with processed antigen and stimulate T cells.

This method has considerable potential for screening novel insulin molecules and formulations and should facilitate the mapping of helper and suppressor epitopes as well as the identification of agretopes involved in the presentation of insulin to T cells.