人骨髓间充质干细胞检测表面氟化处理镁合金材料的细胞相容性

背景：表面氟化处理的AZ31B镁合金是中科院金属研究所新研制的镁合金,是否具有良好的生物相容性尚不确切。 目的：以人骨髓间充质干细胞作为检测细胞,评价表面氟处理的镁合金材料的细胞相容性。 方法：人骨髓间充质干细胞培养并予以鉴定,将镁合金AZ31B作为对照组,氟处理的镁合金AZ31B材料为实验组。以人骨髓间充质干细胞作为检测细胞,取两组材料浸提液进行体外细胞相容性实验,评价氟处理的镁合金AZ31B材料的生物相容性。 结果与结论：与未经氟处理镁合金AZ31B材料相比,经氟处理镁合金AZ31B材料能显著提高细胞存活率,细胞毒性分级１级,对细胞生长基本无毒性作用。结果表明,经氟处理镁合金AZ31B材料生物相容性优于未经氟处理镁合金AZ31B材料。     

氟转化涂层镁合金材料与诱导后人骨髓间充质干细胞的相容性*

背景：氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金是中科院金属研究所新研制的镁合金,是否具有良好的生物相容性尚不确切。 目的：以诱导的人骨髓间充质细胞作为检测细胞,评价氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料的细胞相容性。 方法：实验分为镁合金AZ31B组,氟转化涂层的AZ31B镁合金组和β-磷酸三钙涂层的AZ31B镁合金组。以诱导的人骨髓间充质细胞作为检测细胞,分别取3种材料浸提液进行体外细胞相容性实验。 结果与结论：氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料细胞毒性分级均为1级,镁合金AZ31B材料细胞毒性分级为2级。提示氟转化涂层的AZ31B镁合金和β-磷酸三钙涂层的AZ31B镁合金材料生物相容性优于未经处理镁合金AZ31B材料。     

微弧氧化AZ31镁合金的生物相容性

背景：表面改性技术和合金成分的变化都会影响到镁合金的生物特性。 目的：探讨微弧氧化处理AZ31镁合金的生物相容性。 方法：将体外扩增培养的兔第3代骨髓基质细胞接种到未处理AZ31镁合金(镁合金+骨髓基质细胞组)和微弧氧化AZ31镁合金(微弧氧化镁合金+骨髓基质细胞组)材料上,另设骨髓基质细胞组做对照。培养1,3,5,7 d观察细胞形态,细胞生长状况,细胞黏附状况,材料表面状况。 结果与结论：3组细胞形态一致,以梭形为主。镁合金+骨髓基质细胞组中细胞生长状况明显不如微弧氧化镁合金+骨髓基质细胞组和骨髓基质细胞组(P < 0.05)。微弧氧化镁合金+骨髓基质细胞组材料表面有大量的细胞附着,并且生长正常,镁合金+骨髓基质细胞组材料表面没有细胞附着,有明显的裂痕(P < 0.05)。结果证实,微弧氧化处理AZ31镁合金具有良好的生物相容性,有利于细胞的附着和正常生长。     

丝素蛋白/壳聚糖复合支架材料的细胞相容性**

背景：大量研究表明丝素蛋白、壳聚糖为天然高分子材料,具有良好的细胞生物相容性。 目的：探讨丝素蛋白/壳聚糖复合支架材料与诱导的兔骨髓间充质干细胞的生物相容性。 方法：将兔骨髓间充质干细胞分离培养、诱导后,与丝素蛋白/壳聚糖三维支架材料体外共培养,以材料的细胞毒性、细胞增殖活力、材料细胞黏附率及扫描电镜等检测评价材料的细胞相容性。 结果与结论：经诱导后的骨髓间充质干细胞在支架材料上黏附、生长良好,保持正常的分裂增殖速度;随时间的增加,细胞黏附率增加,材料组较对照组黏附率强,差异有显著性意义(P < 0.05)。扫描电镜观察发现细胞接种48 h后细胞生长良好,与支架黏附紧密,增殖分裂活跃。说明丝素蛋白/壳聚糖三维支架材料具有良好的细胞相容性。     

二元镁合金在细胞培养基中的耐腐蚀能力及其生物相容性

背景：尽管已经有很多研究报道镁及其合金具有一定的骨传导性和可降解性,可以做为承重骨科内植物材料,但是还需要做更多的工作来正确评估它的潜力所在。 目的：检测镁和二元镁合金在细胞培养基中的降解特性和对成人骨髓间充质干细胞活性的影响。 方法：制备纯镁和8种二元镁合金(Mg-Al、Mg-Ca、Mg-Mn、Mg-Sn、Mg-Si、Mg-Y、Mg-Zn、Mg-Zr)样品;采用α-MEM细胞培养基(含体积分数为10%胎牛血清)模拟体内环境下制备标准浸提液,并检测pH值;电感耦合等离子体原子发射光谱仪检测浸提液中镁和添加元素含量;Alamar Blue法检测培养达1,3,5,7 d时100%、50%、25%浓度的纯镁和8种镁合金浸提液对成人骨髓间充质干细胞增殖的影响,判断８种二元镁合金的生物相容性。 结果与结论：Mg-Ca、Mg-Y合金耐腐蚀性较差,浸提液中Mg²⁺质量浓度分别达到(408.0±37.9) mg/L 和(351±15.3) mg/L,pH值分别为8.87±0.19和8.84±0.15;其次是Mg-Zr合金;其他二元合金耐腐蚀性与纯镁相当。结果表明纯镁和8种二元镁合金100%含量的浸提液均对成人骨髓间充质干细胞的增殖有显著抑制作用,当Mg²⁺质量浓度低于110 mg/L,pH值7.35~7.65时,纯镁和8种二元镁合金对成人骨髓间充质干细胞的增殖无显著影响。     

异种生物衍生骨材料与骨髓间充质干细胞的生物相容性

背景：异种生物衍生骨保存了原骨组织的天然网状孔隙结构,且具有免疫原性低、细胞相容性好的特点。目的：验证异种生物衍生骨材料与骨髓间充质干细胞的生物相容性。方法：取新鲜猪股骨制备生物衍生骨,扫描电镜观察材料结构。将第3代兔骨髓间充质干细胞以2×10⁹ L^-1的浓度接种于生物衍生骨材料的松质骨面,复合培养7 d内,采用扫描电镜观察细胞生长情况;复合培养8 d内,计数材料上附着的细胞数。结果与结论：生物衍生骨表面粗糙,孔隙不规则并相互通联,构成网状结构。复合培养3 d,细胞在衍生骨材料表面发生附着,且细胞形态不均一;复合培养培养 5 d,细胞连接成片呈层状生长,细胞之间紧密接触;复合培养7 d,细胞呈现多层生长状态,成堆生长,部分区域存在细胞外基质分泌现象。复合培养后,前2 d 为潜伏适应期,3-6 d细胞生长呈出线性曲线,处于细胞生长对数期;第 6 天后,细胞生长曲线逐渐变得平缓,细胞增殖速度下降,增殖进入平台期。表明异种生物衍生骨材料与骨髓间充质干细胞具有良好的生物相容性。 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程      

镁合金AZ31B材料表性与成骨细胞的黏附

背景：镁合金对成骨细胞的生物学行为及早期黏附是否有影响尚不明确。 目的：分析镁合金AZ31B的表性,并评价其对成骨细胞黏附的影响。 方法：采用扫描电镜及能谱分析明确镁合金AZ31B的表面形态及元素组成。以蛋白吸附实验检测镁合金AZ31B与钛合金对蛋白的吸附能力。将镁合金AZ31B与钛合金分别与小鼠前成骨细胞MC3T3-El共培养于24孔板内,观察培养2,6,24 h的细胞黏附情况。 结果与结论：扫描电镜可见镁合金AZ31B表面较为粗糙,有利于细胞在其表面的黏附.能谱分析结果表明镁合金AZ31B的主要元素有镁、铝、锌,其中镁约占96%,铝约占3%,锌约占1%,另有一些其他元素,含量较少。镁合金AZ31B与钛合金的蛋白吸附率差异无显著性意义。培养2 h时,镁合金AZ31B与钛合金上的细胞黏附率差异无显著性意义;培养6,24 h,镁合金AZ31B上的细胞黏附率显著低于钛合金上的细胞黏附率(P < 0.01)。培养于镁合金表面的成骨细胞贴壁展开,形态不规则,大多呈梭形,有较多突起,部分细胞间突起相互连接。表明镁合金AZ31B具有良好的细胞黏附性,适合于成骨细胞的早期黏附。     

猪小肠黏膜下层与兔骨髓间充质干细胞的体外复合培养

背景：小肠黏膜下层细胞外基质材料免疫原性低,具有良好生物相容性,是构建单一结构工程化组织的较好支架材料。 目的：观察体外兔骨髓间充质干细胞与猪小肠黏膜下层复合培养的生物相容性。 方法：采用密度梯度离心法结合贴壁法分离纯化培养兔骨髓间充质干细胞,在其接种前用红色免疫荧光标记,然后将第2代已标记的兔骨髓间充质干细胞接种在猪小肠黏膜下层上。 结果与结论：①组织学观察：骨髓间充质干细胞与小肠黏膜下层上复合培养1周时细胞呈单层生长,荧光显微镜下观察标记的骨髓间充质干细胞显示均匀红色荧光,复合培养2周细胞呈多层生长,并显示更密集的红色荧光。②扫描电镜观察：复合培养2 d,骨髓间充质干细胞黏附于材料表面并伸展;复合培养1周,小肠黏膜下层被骨髓间充质干细胞分泌的胶原覆盖;2周后细胞在材料上已大量增殖形成融合,细胞连接紧密,细胞分泌大量基质,并分层。表明小肠黏膜下层与骨髓间充质干细胞具有良好的相容性。     

兔骨髓间充质干细胞与异体脱细胞耳软骨支架的体外复合*

背景：耳软骨作为脱细胞基质可选择的支架,进行脱细胞处理可去除了软骨细胞的抗原性,从而与种子细胞具有良好的相容性。 目的：体外提取、培养兔骨髓基质干细胞,并与异体脱细胞耳软骨支架复合,观察其生物相容性。 方法：提取兔骨髓间充质干细胞行体外培养,诱导为软骨细胞,以胰蛋白酶-曲拉通联合法获得脱细胞软骨支架,将两者于体外复合,10 d后复合支架固定行组织学染色及扫描电镜观察。 结果与结论：兔骨髓间充质干细胞体外诱导14 d可形成软骨细胞,Ⅱ型胶原免疫细胞化学示胞浆呈棕黄色;兔耳软骨脱细胞基质呈乳白色,组织学染色及扫描电镜观察示经脱细胞后支架孔隙均匀,结构完整,仍保存大量酸性黏多糖及胶原成分。其孔径长度(33.70±4.33) μm,孔隙率(65.23±7.35)%。 复合支架组织学染色及扫描电镜示两者黏附良好,并伴有多量基质分泌。说明兔骨髓间充质干细胞诱导为软骨细胞与异体脱细胞耳软骨有良好的生物相容性。     

魔芋葡甘聚糖/透明质酸共混膜的体外细胞生物相容性

背景：高分子材料透明质酸与魔芋葡甘聚糖均可用于防治术后粘连。 目的：观察兔骨髓间充质干细胞与魔芋葡甘聚糖-透明质酸共混膜复合培养的生物相容性。 方法：取第3代兔骨髓间充质干细胞与魔芋葡甘聚糖-透明质酸共混膜体外复合培养,倒置显微镜和扫描电镜观察复合程度,MTT法检测细胞增殖。体外定向外诱导魔芋葡甘聚糖-透明质酸共混膜上的骨髓间充质干细胞向脂肪细胞分化,油红O染色检测其分化效果。 结果与结论：骨髓间充质干细胞与魔芋葡甘聚糖-透明质酸共混膜修复材料复合良好,倒置显微镜和扫面电镜观察均可见细胞在共混膜上良好黏附与增殖;体外定向诱导魔芋葡甘聚糖-透明质酸共混膜上的骨髓间充质干细胞可向脂肪细胞分化,具有成脂潜能。说明魔芋葡甘聚糖-透明质酸共混膜与骨髓间充质干细胞具有良好的生物相容性。     

In vitro and in vivo assessment of biocompatibility of AZ31 alloy as biliary stents: a preclinical approach

IntroductionBiomaterial technology due to its lack of or minimal side effects in tissues has great potential. Traditionally biomaterials used were cobalt-chromium, stainless steel and nitinol alloys. Biomaterials such as magnesium (Mg) and zinc (Zn) have good biocompatibility and consequently can be a potential material for medical implants. To date, the effects of AZ31 alloy stent on cell apoptosis are still unclear. The current investigation was designed to determine the effect of AZ31 alloy stent on necrosis and apoptosis of common bile duct (CBD) epithelial cells.Material and methodsWe experimented with application of different concentrations of AZ31 alloy stent to primary mouse extrahepatic bile epithelial cells (MEBECs) and estimated the effect on apoptosis and necrotic cells. Apoptosis and pro-apoptosis expression were estimated through real-time PCR. For in vivo protocol, we used rabbits, implanted the AZ31 bile stent, and estimated its effect on the CBD. AZ31 (40%) concentration showed an effect on the apoptotic and necrotic cells.ResultsReal-time PCR revealed that AZ31 (40%) concentration increased the apoptotic genes such as NF-κB, caspase-3, Bax and Bax/Bcl-2 ratio as compared to the control group. In the in vivo experiment, AZ31 alloy stents were implanted into the CBD and showed an effect on the alteration the hematological, hepatic and non-hepatic parameters.ConclusionsTo conclude, it can be stated that AZ31 induces apoptosis via alteration in genes including nuclear factor kappa-B (NF-κB), caspase-3, Bax and Bax/Bcl-2 ratio and improved the hematological, hepatic and non-hepatic parameters.     

Loss of mechanical properties in vivo and bone–implant interface strength of AZ31B magnesium alloy screws with Si-containing coating

In this study the loss of mechanical properties and the interface strength of coated AZ31B magnesium alloy (a magnesium–aluminum alloy) screws with surrounding host tissues were investigated and compared with non-coated AZ31B, degradable polymer and biostable titanium alloy screws in a rabbit animal model after 1, 4, 12 and 21 weeks of implantation. The interface strength was evaluated in terms of the extraction torque required to back out the screws. The loss of mechanical properties over time was indicated by one-point bending load loss of the screws after these were extracted at different times. AZ31B samples with a silicon-containing coating had a decreased degradation rate and improved biological properties. The extraction torque of Ti6Al4V, poly-l-lactide (PLLA) and coated AZ31B increased significantly from 1 week to 4 weeks post-implantation, indicating a rapid osteosynthesis process over 3 weeks. The extraction torque of coated AZ31B increased with implantation time, and was higher than that of PLLA after 4 weeks of implantation, equalling that of Ti6Al4V at 12 weeks and was higher at 21 weeks. The bending loads of non-coated AZ31B and PLLA screws degraded sharply after implantation, and that of coated AZ31B degraded more slowly. The biodegradation mechanism, the coating to control the degradation rate and the bioactivity of magnesium alloys influencing the mechanical properties loss over time and bone–implant interface strength are discussed in this study and it is concluded that a suitable degradation rate will result in an improvement in the mechanical performance of magnesium alloys, making them more suitable for clinical application.     

Corrosion protection and improved cytocompatibility of biodegradable polymeric layer-by-layer coatings on AZ31 magnesium alloys

Composite coatings of electrostatically assembled layer-by-layer anionic and cationic polymers combined with an Mg(OH)₂ surface treatment serve to provide a protective coating on AZ31 magnesium alloy substrates. These ceramic conversion coating and layer-by-layer polymeric coating combinations reduced the initial and long-term corrosion progression of the AZ31 alloy. X-ray diffraction and Fourier transform infrared spectroscopy confirmed the successful application of coatings. Potentiostatic polarization tests indicate improved initial corrosion resistance. Hydrogen evolution measurements over a 2 week period and magnesium ion levels over a 1 week period indicate longer range corrosion protection and retention of the Mg(OH)₂ passivation layer in comparison to the uncoated substrates. Live/dead staining and DNA quantification were used as measures of biocompatibility and proliferation while actin staining and scanning electron microscopy were used to observe the cellular morphology and integration with the coated substrates. The coatings simultaneously provided improved biocompatibility, cellular adhesion and proliferation in comparison to the uncoated alloy surface utilizing both murine pre-osteoblast MC3T3 cells and human mesenchymal stem cells. The implementation of such coatings on magnesium alloy implants could serve to improve the corrosion resistance and cellular integration of these implants with the native tissue while delivering vital drugs or biological elements to the site of implantation.     

Corrosion resistance of a composite polymeric coating applied on biodegradable AZ31 magnesium alloy

The high corrosion rate of magnesium alloys is the main drawback to their widespread use, especially in biomedical applications. There is a need for developing new coatings that provide simultaneously corrosion resistance and enhanced biocompatibility. In this work, a composite coating containing polyether imide, with several diethylene triamine and hydroxyapatite contents, was applied on AZ31 magnesium alloys pre-treated with hydrofluoric acid by dip coating. The coated samples were immersed in Hank’s solution and the coating performance was studied by electrochemical impedance spectroscopy and scanning electron microscopy. In addition, the behavior of MG63 osteoblastic cells on coated samples was investigated. The results confirmed that the new coatings not only slow down the corrosion rate of AZ31 magnesium alloys in Hank’s solution, but also enhance the adhesion and proliferation of MG63 osteoblastic cells, especially when hydroxyapatite nanoparticles were introduced in the coating formulation.     

镁及镁合金植入体在骨科临床中的应用与进展

背景：镁是可被人体吸收的常量元素,作为医用生物材料具有明显的优势。 目的：综述镁及镁合金在骨科应用中的优点、缺点及近年来国内外的研究进展。 方法：由第一作者检索2000/2011 PubMed数据及CNKI数据库有关镁离子合金在医疗领域的研究进展等方面的文献。 结果与结论：传统医用金属材料包括不锈钢、钴基合金和钛基合金存在生物相容性差、生物力学性能不匹配、需要二次手术等弊端,镁合金具有良好的生物力学相容性、可降解性能、生物安全性,并且资源丰富。可在生理电解质环境中通过腐蚀而发生降解的特性,在骨科领域展示了巨大的潜在应用前景。     

Influence of surface modification on the in vitro corrosion rate of magnesium alloy AZ31

In recent years, magnesium alloys have been proposed as a new class of metallic bioabsorbable implant material. Unfortunately, the production of hydrogen gas and an increase in alkalinity are both by-products of the degradation process of these materials. This necessitates the development of magnesium alloys with controlled degradation rates. Furthermore, biocompatible coatings that can delay the onset of corrosion would ensure that the mechanical integrity of the implant remains intact in the early stages of healing. This article explores the influence of surface modification by biomimetic calcium phosphate coating, biodegradable polymer coatings, and acid etching on the corrosion rate of the AZ31 magnesium alloy in simulated body fluid. Our results indicate that all of these surface treatments have a positive impact on the corrosion rate of the material and that in the early stages of implantation it is possible to tailor the corrosion rate through an appropriate choice of surface treatment.