骨组织损伤修复生物医用材料的研究进展

人工骨修复材料在骨组织工程中具有许多潜在的用途和优势，近年来引起了许多研究人员的关注。本文介绍了用于骨组织修复的高分子材料、陶瓷材料、金属材料以及仿生纳米羟基磷灰石／胶原和纳米羟基磷灰石／聚酰胺等复合材料。指出仿生骨生物医用修复材料是今后该领域的发展趋势。     

不同多孔PLGA／纳米羟基磷灰石复合支架加载辛伐他汀药物释放性能的研究

目的研究不同多孔PLGA／纳米羟基磷灰石复合支架加载辛伐他汀的药物释放性能。方法采用PLGA颗粒和纳米羟基磷灰石颗粒为原料，制备五种加载辛伐他汀的复合支架材料，并用分光光度仪测定每种复合支架材料辛伐他汀释放情况。结果加载辛伐他汀的五种类型复合支架，体外药物释放均呈缓慢持续性释放达到60d以上，60天累积释放率达70～90％，其中采用产气颗粒沥析技术的两种支架材料释放速度较为均衡。结论加载辛伐他汀的多孔PLGA／纳米羟基磷灰石复合支架具有良好的药物释放性能。     

不同多孔PLGA/纳米羟基磷灰石复合支架的制备及机械物理性能研究

目的研究不同方式的多孔PLGA/纳米羟基磷灰石复合支架的制备及机械物理性能。方法采用PLGA颗粒和纳米HA颗粒为原料,制作多孔PLGA（产气颗粒沥析技术）、多孔PLGA（溶液浇注/颗粒沥析技术）、纳米羟基磷灰石、多孔PLGA/纳米羟基磷灰石（产气颗粒沥析技术）、多孔PLGA/纳米羟基磷灰石（溶液浇注/颗粒沥析技术）五种支架,分别对支架的抗压强度、孔隙率、保水率等机械物理性能进行研究。结果成功制备五种类型的复合支架,其性能均达到了较好的机械物理效果,其中纳米羟基磷灰石支架的保水率最高,多孔复合支架展现了较好的抗压强度,产气颗粒沥析技术得到了更高的孔隙率。结论多孔PLGA/纳米羟基磷灰石复合支架具有良好的机械物理性能,产气颗粒沥析技术能制备出更高孔隙率的支架材料。     

掺锶纳米羟基磷灰石复合釉质粘结的体外研究

目的:体外检测掺锶纳米羟基磷灰石作为填料与釉质粘结剂复合后的粘结强度和再矿化作用。方法:将掺锶纳米羟基磷灰石按不同质量比(0%、8%、10%、12%、14%)、纳米羟基磷灰石按一定质量比(10%)与京津釉质粘结剂复合后分别粘结托槽,电子万能测试机检测托槽粘结强度,并计算ARI记分,对结果进行统计学处理与分析。用扫描电镜观察12%掺锶纳米羟基磷灰石粘结剂、10%纳米羟基磷灰石粘结剂和0%粘结剂对托槽周围脱矿釉质的再矿化情况。结果:12%掺锶纳米羟基磷灰石粘结剂剪切强度和拉伸强度均高于其他各组,与10%纳米羟基磷灰石粘结剂、0%粘结剂有显著差异(P0.05);各组ARI记分之间无显著差异(P0.05);12%掺锶纳米羟基磷灰石粘结剂再矿化效果优于其他各组。结论:12%掺锶纳米羟基磷灰石釉质粘结剂较其他各组具有良好的机械性和再矿化作用。     

羟基磷灰石在阻生齿拔除术后的临床应用（附50例报道）

羟基磷灰石具有良好的组织相容性和明显的骨引导作用，已成为一种有潜力的骨缺损修复材料。我院自１９９４年起对５０例阻生齿拔除后立即植入羟基磷灰石颗粒及甲硝唑注射液，临床上取得了良好效果，报告并讨论如下。１材料与方法选用四川大学材料研究所研制的羟基磷灰石微...     

多孔型羟基磷灰石的生物相容性

多孔型羟基磷灰石的生物相容性邱书明，郑华，王定国，吴增树四川省劳动卫生职业病防治研究所６１００４１实验和临床证实羟基磷灰石是能替代自体骨的新型人工骨材料，是一种无毒、无刺激、不溶血、组织相容性好的高分子材料。本实验采用多孔化处理的羟基磷灰石人工骨材料...     

透明质酸/壳聚糖复合支架的制备及成骨的实验研究

目的模拟天然骨组织的结构和成分,寻找适合骨组织工程的新型支架材料。方法以透明质酸、壳聚糖为基质材料,制备出一种深度矿化的透明质酸/壳聚糖复合支架。通过SEM、EDS等对支架进行表征,研究支架的形貌、成分及力学强度等性能,并通过原位植入兔股骨髁上骨缺损,通过组织学等手段检测其骨修复效果。结果 SEM观察显示,支架材料具有比较均匀的多孔结构,孔径大小为100²00μm。EDS结果表明,复合支架在一次冻干之后形成的是磷酸氢钙(DCPD),随着陈化时间的延长,DCPD逐渐向羟基磷灰石(HAP)转化。透明质酸/壳聚糖复合支架在兔体内能够修复大段骨缺损。结论透明质酸/壳聚糖复合支架可作为骨组织工程的新型支架材料用于修复骨缺损。     

聚乳酸类支架材料研究进展

组织工程学是在细胞生物学、分子生物学、生物材料学和临床医学基础上发展起来的一门交叉学科，其目的是以生物替代物修复和改善人体损伤组织的功能。而组织工程学的根本在于研究和开发生物替代物的支架材料，该材料需具备如下特性：(1)组织相容性；(2)生物可降解性；(3)降解可调性；(4)降解无毒性；(5)易于塑型；(6)具有适应种子细胞生长、繁殖所需要的物理和化学特性。而目前研究最广泛的具有上述特性的材料是聚羟基乙酸和聚乳酸等聚乳酸类材料。聚乳酸类材料已被广泛用于骨、软骨、血管、神经、皮肤等组织的支架材料。本文对聚乳酸类组织工程支架材料的制备、改进及其在组织工程中的应用进展作一综述。     

羟基磷灰石经氯磷酸二钠表面改性对成骨细胞的影响

目的研究经氯磷酸二钠表面改性的羟基磷灰石对成骨细胞生长、贴附、蛋白合成方面及骨吸收功能调节方面的影响。方法将成骨细胞分别复合羟基磷灰石与氯磷酸二钠复合制成氯磷酸二钠－羟基磷灰石表面，扫描电镜进行细胞形态学观察，通过MTT法和碱性磷酸酶活力检测考察表面改性对成骨细胞生长、增殖和活性影响；同时应用荧光定量PCR比较两组材料表面成骨细胞OPG和RANKL基因表达，考察表面改性对成骨细胞骨吸收功能调节方面的影响。结果扫描电镜显示成骨细胞生长和增殖良好，无形态学异常；统计学检验（P〉0．05），MTT检测和ALP活性两组之间各时间点均没有统计学差异；基因检测发现成骨细胞OPG基因表达组间有显著差异，P〈0．05；RANKL基因表达组间无明显差异，P〉0．05。结论氯磷酸二钠复合在羟基磷灰石表面对成骨细胞在材料表面的生长、增殖和蛋白合成功能没有显著影响；但是表面改性可促进成骨细胞OPG基因表达，这可能是氯磷酸二钠影响成骨细胞的破骨细胞调节功能的机理之一。     

骨诱导性磷酸钙陶瓷——从基础研究到临床应用

本文阐述了生物材料骨诱导作用的立论出发点,结合材料诱导骨形成的组织学和分子生物学证据和材料组成、结构特别是微纳米结构对干细胞和成体细胞基因表达及行为的调控作用,归纳材料骨诱导作用的机理,提出具有骨诱导作用的生物材料设计原理及评价材料骨诱导作用的生物安全性方法,展示骨诱导生物材料从概念、基础研究、到实验室样品转化为小批量生产及临床应用的过程。     

骨组织工程高分子材料和复合材料的研究进展

支架材料是骨组织工程三大因素之一,作为一种载体,为细胞提供生存的三维空间。本文阐述了近年来常见高分子材料及复合材料的国内外研究进展,并分析了各种材料的优缺点。最后,指出了目前支架材料研究中仍存在的问题,并对其发展前景进行了展望。     

高频无铅压电超声换能器研究进展

高频无铅压电超声换能器已经成为当前超声医学领域及压电材料领域研究的热点。本文根据近期国内外报道的有关高频无铅压电超声换能器的进展,对无铅压电陶瓷超声换能器、无铅压电单晶超声换能器、无铅压电高分子聚合物超声换能器、无铅压电薄膜超声换能器及无铅压电复合物超声换能器的性能进行了总结,并与报道的高频铅基压电超声换能器的性能做比较,以期对高频无铅压电超声换能器的研究和应用提供参考。     

Bis—GMA／Nano（SiO2-ZrO2）复合树脂牙科材料的制备

目的：对纳米复合树脂牙科材料的制备方法进行研究，从工艺上解决纳米复合材料不够致密问题，使之能较多地应用于临床牙科材料中。方法：用双酚A-甲基丙烯酸缩水甘油酯（Bis—GMA）和双甲基丙烯酸二缩三乙二醇酯（TEGDMA）共同作为树脂基质，利用经过表面处理的纳米无机填料中的一种或者几种填料混合添加制备复合材料，同时采用原位分散法用高速搅拌和超声分散等制备工艺来改善纳米填料分散体系，运用DTA、XRD、SEM等实验手段对Bis—GMA／Nano（SiO2-ZrO2）纳米复合树脂材料进行性能测试及结构表征。结果：利用经过硅烷偶联剂表面处理的纳米SiO2和ZrO2可均匀分散在Bis—GMA基体中．所获得纳米颗粒增强体质量分数高达30％复合材料．制备出了一种力学性能好（致密性高、耐磨性强和硬度大）的数控加工用纳米复合树脂牙科材料。结论：该方法制备出的高性能Bis—GMA／nano（SiO2-ZrO2）复合树脂牙科材料，既美观又坚韧，能充分满足临床牙科修复学需要。     

Microtomography evaluation of dental tissue wear surface induced by in vitro simulated chewing cycles on human and composite teeth

In this study a 3D microtomography display of tooth surfaces after in vitro dental wear tests has been obtained. Natural teeth have been compared with prosthetic teeth, manufactured by three different polyceramic composite materials. The prosthetic dental element samples, similar to molars, have been placed in opposition to human teeth extracted by paradontology diseases. After microtomography analysis, samples have been subjected to in vitro fatigue test cycles by servo-hydraulic mechanical testing machine. After the fatigue test, each sample has been subjected again to microtomography analysis to obtain volumetric value changes and dental wear surface images. Wear surface images were obtained by 3D reconstruction software and volumetric value changes were measured by CT analyser software. The aim of this work has been to show the potential of microtomography technique to display very clear and reliable wear surface images. Microtomography analysis methods to evaluate volumetric value changes have been used to quantify dental tissue and composite material wear.     

Performance of Red Mud/Biochar Composite Material (RMBC) as Heavy Metal Passivator in Pb-Contaminated Soil

Bulletin of Environmental Contamination and Toxicology - Red mud/biochar composite material (RMBC), which was applied as heavy metal passivator in this research, was prepared with red mud (the...     

Studies on composites of collagen and a synthetic polymer. Second report - mode of reaction of a laminar composite with living tissue, and results of long-term implantation.

We have been studying composites of synthetic polymers and proctase-treated bovine collagen (telopeptide-poor collagen). In a previous paper, it is described that one of our composites appears to have a high tissue affinity, because it was found under a scanning electron microscope, well bonding the living tissue 6 weeks after implantation in the rabbit subcutaneous tissue. In the present study, the composites were also implanted in the subcutaneous tissue in rabbits to observe the mode of its bonding to the living tissue, and at the same time the bonding force was measured at various intervals during a period of 1.5 years, to observe the degree and duration of the effect of the composition, and further to study the optimal conditions for preparation of such a composite. As a method of composition, ultraviolet radiation and glutaraldehyde treatment were also comparatively examined, besides gamma-radiation that had been employed in a previous study. As the results, it is revealed that the composite bonds to the living tissue in such a manner that a portion of the collagen part is digested and absorbed to be replaced by the invading connective tissue and a part of collagen near the surface of the synthetic polymers had escaped digestion to combine with the rabbit's own collagen fiber. From these results we like to insist that the mode of reaction of our composites may be similar to real organization and be different in natur from mere encapsulation which was shown by the artificial materials hitherto in use to be considered to have a good tissue affinity. Therefor we think now the encapsulation is pseudoorganization. It is also shown that the bonding force of the composite to the living tissue and its duration depend chiefly on the degree of swelling, that is, the degree of intermolecular cross-linking, of the composed collagen part. Out of the gamma-radiated composites, those radiated 1--3 Mrads proved desirable in both tissue affinity and duration of tissue bonding, with a potent bonding force remaining effective even 1.5 years later, while the composite radiated with 5 Mrads or more proved poorer in these properties because of destruction of the collagen part, vastly varying in the properties. By ultraviolet radiation, it was easy to control the degree of swelling of collagen part with the radiation dose, however, this method gave a lower bonding force and a shorter duration of the force than gamma-radiation. The glutaraldehyde method allowed the collagen to remain over a long time, but gave the composite less tissue affinity than the other two methods.     

骨髓间充质干细胞分化为成骨细胞优化生物活性玻璃的实验研究

目的研究兔成骨细胞在生物活性玻璃复合材料支架中的生长情况,探讨优化组织工程中生物材料支架的实验方法。方法分离并培养兔骨髓间充质干细胞(MSCs),应用成骨诱导剂诱导MSCs向成骨细胞分化、发育;在显微镜下观察细胞形态学变化;通过细胞活性、免疫组化鉴定诱导培养的成骨细胞的细胞学特性。将成骨细胞分别附着在3种不同生物活性玻璃组成的新型材料支架中,进行共培养,观察细胞的变化,从而比较不同生物活性玻璃与成骨细胞的相容性。结果MSCs经成骨诱导剂诱导后:细胞数量明显增多,细胞形态向多角形及类圆形转化。经诱导的兔成骨细胞与生物活性玻璃组成的材料支架融合后,发现兔成骨细胞在孔隙率为75.90%的支架中增殖较慢;在孔隙率为90.20%和94.50%的生物活性玻璃复合材料支架中生长良好,增殖较快,孔隙及周围有大量成骨细胞附着。结论具有适宜孔隙率的生物活性玻璃复合材料有望成为培养人工骨的种子支架,为骨组织工程的临床应用奠定了实验基础。     

Scanning and transmission electron microscopy of calcified tissues.

Some recent innovations have been utilized to extend studies of the structure of calcified tissues on the ultra- and microstructural levels of organization. The introduction of hydrazine as a replacement for the conventionally used ethylene diamine to deproteinize calcified tissue samples has resulted in the acquisition of previously unobtainable information about the mineral phase as it exists in situ. This enables inference of mineral-organic interrelationships when coupled with the EDTA demineralization technique used to study collagen fiber frameworks. In addition, a method for obtaining whole single osteons and separating them into lamellar constituents permits observations of the collagen-apatite orientation within successive lamellae of compact Haversian bone. The use of the structural information derived to develop a fiber-reinforced model of compact bone as a composite material is outlined and discussed.     

生物玻璃增强羟基磷灰石陶瓷支架性能研究

骨修复材料的选择一直是困扰研发和临床的新问题．主要涉及材料的坚固性以及其生物相容性。磷酸钙陶瓷属于生物活性陶瓷,成为人工骨替代的研究热点．但材料本身的机械强度制约了其发展。在磷酸钙陶瓷里加入生物玻璃不仅增强了它的坚固性,更提高了其生物活性。