心血管移植物体外内皮化研究进展

血液和组织相容性是人工心血管材料的广泛应用中的主要问题之一。对生物材料表面加以修饰是改善其相容性的常用方法。对生物材料表面进行内皮化处理很好地改善了生物材料的血液和组织相容性，在临床应用中表现出较好的效果。本文综述了此方面的进展并对存在的一些问题进行了探讨。     

“心灵感应”汽车：打个响指能开门

由天津大学－GKSS研究中心生物材料及再生医学联合实验室、天津市胸科医院、中国科学院共同研发的国产心脏体外辅助装置现已基本加工成型。据负责该项目的天津大学化工学院高分子系冯亚凯教授介绍,此次我国联合攻关主要解决的核心问题就是心脏体外辅助装置的材料制备和血液相容性等问题,还有“人工心脏”加工成型和成型后内表面仿生化修饰等技术问题。     

T-1型脱细胞异体组织补片生物相容性评价研究

T-1型脱细胞异体组织补片主要用于口腔软组织损伤、疝气等修补的新型生物材料.为了确保产品在临床使用的安全有效性,我们对其进行了细胞毒性、皮肤致敏、口腔粘膜刺激以及动物体内的肌肉植入等一系列生物相容性评价试验.结果表明该补片具有细胞毒性小、无致敏、无口腔粘膜刺激反应,具有良好的生物相容性以及较好的体内组织化作用.     

医学工程中的研究重点

医学工程所要研究的课题很广,它涉及医学的许多不同的方面,包括齿科材料、体内假体、体外辅助装置、诊断和成象。但主要研究下列几个方面。 1.生物相容性:生物材料的物理和化学结构的基础研究及其有关生物相容性试验,包括植入物表面特性的研究。     

血液灌流器滤芯中吸附树脂的体外血液相容性评价

目的研究吸附树脂原料进行进一步加工处理的必要性。方法依据GB／T16886．4的有关规定．通过凝血试验．血液学试验．体外自发性血小板粘附试验及补体激活试验对吸附树脂原料进行体外血液相容性评价。结果与聚丙烯相比较，吸附树脂原料是内源性凝血系统的极轻微激活剂．对外源性凝血系统有极显著性抑制作用（P〈0．01），对纤维蛋白原、红细胞及网织红细胞呈现极显著性粘附作用（P〈0．01）．对血小板有显著性粘附作用（P〈0．05），吸附树脂原料同时也是补体系统的极显著性激活剂（P〈0．01）。结论体外血液相容性评价表明：吸附树脂原料必需经过特定的工艺（如表面修饰、微囊化技术等）才可用于人体。     

壳聚糖的生物学评价

壳聚糖是从虾蟹中提取的一种新型天然生物材料，易成膜，具有很好的生物降解性和生物相容性。为开发壳聚糖在医药卫生和化妆品等领域的应用，本实验对其进行了生物学评价。现报告如下。     

可复性输卵管避孕材料应用进展

从材料构成、性能、应用、实验等4个方面,阐述了输卵管避孕栓应用材料的性能、用法、生物相容性及其发展动态,分析和比较避孕栓材料的优劣性,对生物材料在计划生育领域的发展趋势进行了展望,指出随着材料学的发展,生物相容性好、可降解、有记忆功能的生物材料在输卵管避孕方面有巨大的应用潜力。     

预防再狭窄的冠状动脉支架的研究进展

针对冠状动脉支架植入后的再狭窄问题．分析得出血管损伤、血流动力学形态的变化和血管壁面剪应力的下降或振荡而引起的内膜增生和血栓形成是再狭窄的主要成因。文中对显著影响再狭窄的材料的生物相容性、支架表面处理．支架结构设计和血流动力学分析等关键技术进行了综述,重点从体内实验、体外实验和计算流体动力学（CFD）等方面介绍了支架植入后血流动力学情况的研究现状。最后描述了作者所在实验室提出的定量研究支架血管耦合系统力学行为的CFD模型和实验方法。     

血液透析中监测技术的研究近况

在血液透近过程中,对患者生理参数的监测直接影响治疗效果。因此,其监测技术的发展受到了国内外学者的广泛重视,现就有关文献综述如下。1 生理参数的分类血液透析治疗涉及患者身体和血液透析仪两个方面。血透仪主要监测患者体外生理参数,包括透析液的电导率和温度、透析器、气泡、透析压、动静脉压等指标。而患者的体内生理参数则由独立配置的附属设备实施监测。过去,人们只看重体外生理参数的观察和测定,忽略了体内生理参数的作用。随着临床医学的发展,人们逐渐认识到体内生理参数才是衡量透析治疗是否成功的关键指标,研究工作的重心也因此转     

医用金属材料的腐蚀测量

概述了生物体用金属材料在体内及在玻璃容器中的腐蚀测量技术及其实验结果。依据实验数据，讨论了用作人工关节、骨折连接板等金属生物材料的腐蚀现象。介绍了金属离子溶出、开路电位、再钝化电位、现钝化电流、交流阻抗、表面分析测量技术在金属生物材料这一领域中的应用。详述了在金属生物材料研究中，腐蚀测量技术所使用的实验溶液及其特性。实验溶液成分为模拟体液，其温度、pH值及溶解氧浓度受控制。     

Toward new biomaterials.

Polymers are widely used for a large range of medical devices used as biomaterials on a temporary, intermittent, and long-term basis. It is now well accepted that the initial rapid adsorption of proteins to polymeric surfaces affects the performance of these biomaterials. However, protein adsorption to a polymer surface can be modulated by an appropriate design of the interface. Extensive study has shown that these interactions can be minimized by coating with a highly hydrated layer (hydrogel), by grafting on the surface different biomolecules, or by creating domains with chemical functions (charges, hydrophilic groups). Our laboratory has investigated the latter approach over the past 2 decades, in particular the synthesis and the biological activities of polymers to improve the biocompatibility of blood-contacting devices. These soluble and insoluble polymers were obtained by chemical substitution of macromolecular chains with suitable groups able to develop specific interactions with biological components. Applied to compatibility with the blood and the immune systems, this concept has been extended to interactions of polymeric biomaterials with eukaryotic and prokaryotic cells. The design of new biomaterials with low bacterial attachment is thus under intensive study. After a brief overview of current trends in the surface modifications of biocompatible materials, we will describe how biospecific polymers can be obtained and review our recent results on the inhibition of bacterial adhesion using one type of functionalized polymer obtained by random substitution. This strategy, applied to existing or new materials, seems promising for the limitation of biomaterial-associated infections.     

In vitro studies on biological effects of fibrous minerals

Asbestos substitutes have been used recently in industrial various applications. Since certain asbestos substitutes have similar characteristics of asbestos, they require urgent in vitro and in vivo evaluation of these asbestos substitutes prior to occupational applications. Though in vitro studies do not offer precise assessment of toxicity of the fibers, it is possible to provide useful information as to the biological effects of asbestos and its substitutes. This review articles described the findings of in vitro experiments in investigation of biological effects of asbestos and man made mineral fibers (MMMF) and their correlation with in vivo assays; 1. Cytotoxicity, geometry and dimension of fibers. 2. In vitro biological effects of fibers on a mass basis and a numerical basis. 3. Mechanism of cytotoxicity, carcinogenecity and cell proliferation including in vitro cytokines production. The relationships between the in vitro and the in vivo biological effects of fibers do not always coincide. Therefore, safety of the fibers must be assessed in both in vivo and in vitro using an inert fiber as negative control. Additionally, evaluation of safety of these fibers in vitro must be conducted in comparable concentrations, sizes and numbers of fibers for used in in vivo experiments.     

Problems and challenges of biomaterials in cardiovascular applications: a status report

Biomaterials used as implants and in various devices must exhibit long-term (years) compatibility with the physiological environment, including blood, and additionally must also remain stable to perform mechanical functions, excepting applications where biodegradation is required. This paper focuses on problems and challenges of polymeric materials in contact with blood in the following categories: (1) artificial heart valves, (2) cardiovascular assist devices and artificial hearts, (3) vascular prostheses, and (4) the biological evaluation of materials prior to their human use, especially with respect to species related hematological differences of experimental animals. Besides thrombosis (which is the most obvious consequence of incompatibility), the calcification of chemically treated tissue prostheses as well as synthetic elastomers used in many cardiovascular devices is discussed in terms of biochemical and physico-chemical parameters together with its significance in long-term (years) implant applications. Complement activation brought about by contact of blood with foreign surfaces has received less than deserved attention in the evaluation of biomaterials and devices, despite the potentially serious problems. Relative ignorance in selecting appropriate animals for the biological evaluation of biomaterials whose hematological profiles and behavior of platelets, red and white cells to trauma and response to foreign surfaces differ decisively from those of humans, often leads to less than meaningful predictions for eventual clinical uses. The state-of-art realities are examined in conjunction with medical, societal, ethical, and economic boundaries.     

Reactivity of blood with biomaterials in vitro: evaluation of some in vitro test systems for estimation of the blood compatibility of biomaterials.

Several different in vitro tests designed to estimate the degree of compatibility of blood with biomaterials have been examined to determine possible effects of donor or donor-material interaction. Statistical evaluation of data was performed, and adequate data were collected with each different test system to render such evaluation meaningful. Isolated examples of donor and donor-material interaction were detected, but these proved to be minor or insignificant in each case. Data are presented for each of the in vitro test systems examined to indicate the number of replicate determinations required for observed differences to be significant at the 5% level.     

论植入体内医用材料的生物相容性

目的：生物相容性是选择研制人工器官和植入用医疗器件用材的首要条件。生物相容性包含组织相容性，和血液相容性两个方面的生物特性。植入材料在体内，被机体视为一种异物体，植入的材料一方面，对生体内环产生不同程度的理化学影响，而另一方面，材料植入在体内也经受着生物内环境的影响。国内外药械管理行政部门，制定了严格的标准，监控材料的生物相容性。文章最后部分，介绍了几种可用于植入用的高分子材料，供参考。     

A comparative analysis of the two approaches to the evaluation of thrombogenic qualities of the biomaterials in vitro

The paper contains an analysis of thrombogeneticity of biomaterials in vitro with regard for the changing time of recalcification of the platelet-free and platelet-related human blood plasma after incubation with a studied sample. Two sizeless thrombogeneticity parameters are suggested for describing the thrombogeneticity of studied biomaterials irrespective of a incubation-medium composition. It was demonstrated by the example of glass granules, which were modified by various immobilized functional groups, that the measuring of re-calcification time performed after samples' incubation secures a more objective assessment of platelet-resistant properties of materials. The relative index of thrombogeneticity of biomaterials (with the above glass granules being the controls), unlike the standardized parameter, opens up the possibility to study comparatively the activating action exerted on the coagulating and anti-coagulating blood systems of the studied samples, which differ by the ratios of their surface squares to the incubation-medium volume.     

生物材料和医疗器械的生物学评价

生物材料和医疗器械的生物学评价是当前生物材料和医疗器械市场和应用能否健康蓬勃发展的关键。随着现代材料科学，生命科学以及医学科学的发展，生物材料在临床医学领域的应用已日趋广泛，而材料和器械的临床前生物学评价则是确研究的现状，存在的问题以及发展趋势等作一简要的评述。     

Hazard assessment of manufactured nanoparticles: association of in vitro and in vivo examinations

Nanoparticles are defined as particles whose diameter is 1-100 nm. Many investigations about the toxicology of nanoparticles have been reported recently. The toxicity of nanoparticles has been examined both in vivo and in vitro and many results are being achieved. However, the results of in vivo and in vitro examinations are sometimes different. According to the in vitro examinations, it is suggested that solubility, adsorption ability and surface activity are involved in the cytotoxicity of nanoparticles. On the other hand, in in vivo, clearance is an important factor in the lung toxicity of nanoparticles. In the hazard assessment of nanoparticles, in vivo and in vitro examinations are necessary for an accurate evaluation of their biological influences, including the toxic mechanisms.     

Use of synthetic mesh and donor grafts in gynecologic surgery

Traditional surgery for the correction of pelvic organ prolapse continues to result in suboptimal long-term cure rates. In an effort to improve clinical outcomes, various new surgical techniques have been proposed and use of synthetic and donor graft has been advocated. Although the technique of graft placement for the correction of anterior, posterior, and apical vaginal wall reconstruction is easy to perform, controversy exists regarding the optimal choice of material. Synthetic materials have the advantage of being readily available, cost-effective, and consistent in quality, but may present with significant complications, including infection and erosion. In contrast, autologous and heterologous donor grafts provide naturally occurring biomaterials that may undergo desired remodelling, but the in vivo tissue response is still not fully understood. The use of graft materials is still in an early period of evaluation and it is expected that its use will steadily rise with increasing experience and new product development. The following review analyzes our current experience with the use of graft materials in reconstructive pelvic surgery.