新型骨科材料SCPP对成骨细胞促血管化生长因子表达影响的研究

在制备聚磷酸钙过程中掺入锶获得掺锶量为(1%、2%、5%、8%、10%)的新型骨科材料SCPP.研究SCPP对成骨细胞行为及其血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)的影响,为阐明其促血管化机理提供实验依据.以成骨细胞与支架材料复合培养,采用XRD,MTT法,ALP活性检测,SEM观察,RT-P...     

钛基掺锶聚磷酸钙涂层的制备工艺及表征

采用等离子喷涂法制备Ti基掺锶聚磷酸钙（SCPP）粉体涂层,通过条件控制制得一系列涂层。利用电感耦合等离子体质谱仪、X射线衍射仪、扫描电子显微镜及万能材料实验机对涂层材料的元素组成、晶相和显微结构及界面结合强度进行分析和表征。分析结果表明,在涂层SCPP中,各元素比例不变,SCPP成分没有发生改变,能够保持原有的晶格结构,未发生相分解等现象,涂层表面略显粗糙且SCPP结合致密,较普通的等离子喷涂具有较好的界面结合强度以及良好的生物相容性。为进一步制备出一种具有适当表面粗糙度和较高界面结合强度的SCPP生物涂层提供了实验基础。     

骨组织工程支架材料聚磷酸钙体外降解规律的研究

为了解决骨组织工程中支架材料的降解速度应与细胞的生长速率相匹配，通过对原料煅烧过程的分析，提出了聚合度的计算方法，并制备出不同聚合度的材料。通过对材料烧结温度的试验，制得了不同晶型的聚磷酸钙多孔材料。结果表明，随着聚合度的增加，材料的抗压强度增大，降解速率变小；不同晶型的材料具有不同的降解速率，非晶CPP最快完全降解为17d，α-CPP最慢30d约降解为5％。凭借其独特的无机聚合物结构及降解性能，实现可控速率的降解。     

碱金属元素掺杂比例对聚磷酸钙降解和矿化性能的影响

用不同比例的碱金属钾(K)和钠(Na)对聚磷酸钙(CPP)进行掺杂改性以期研究其降解与矿化性能.掺杂CPP样品在模拟体液(SBF)中分别浸泡1、2、3、7、14、21、28和35 d,研究其降解和矿化性能.通过测量降解样品的失重率,SBF中Ca~(2+)和PO_4~(3-)的浓度和pH值的变化来表征降解速率.掺杂CPP样品通过X射线衍射法(XRD)、傅里叶红外变换光谱法(FTIR)和扫描电镜(SEM)进行表征.结果显示掺杂摩尔比高于5%的CPP降解速率明显提高.K~+和Na~+掺杂比越高越能有效提高CPP的降解和矿化能力.     

VEGF和SDF-1α对材料表面内皮再生影响的对比研究

血管支架植入后血栓及再狭窄依然是临床上的主要问题。通过材料表面仿生微环境的构建改善支架抗凝性能并加速血管内皮修复是解决上述问题的主要手段。研究表明,VEGF和SDF-1α均可有效介导血管内皮细胞的增殖与迁移。为比较两类因子在内皮化过程中的功能差异,选择在材料表面构建纤连蛋白/肝素功能层,并分别引入VEGF与SDF-1α两种因子,通过XPS和水接触角检测研究修饰表面的理化性质。体外动态释放实验结果显示,修饰层具有良好的控制因子释放的能力。体外细胞相容性评价结果显示,VEGF和SDF-1α均具有刺激内皮细胞增殖和迁移的功能,但VEGF表现出更强烈的调节内皮细胞行为的功能。     

碱矿渣复合胶凝材料固化Sr 2+的效率及机理

通过浸出率试验、SEM及吸附试验,研究了碱矿渣复合胶凝材料固化Sr2＋的效率,分析其固化机理。结果表明,碱矿渣复合胶凝材料固化Sr2＋的效率受碱种类、碱当量以及矿物掺合料的影响。在3.0%~6.0%范围内,随着碱当量的增加,碱矿渣复合胶凝材料固化Sr2＋的效率逐渐提高;Na2O当量相同时,水玻璃作碱组分的胶凝材料固化Sr2＋的效率优于NaOH作碱组分的胶凝材料;硅藻土部分替代矿渣所得胶凝材料固化Sr2＋的效果优于高岭土、沸石粉,且随着硅藻土掺量的增加,固化基体对Sr2＋的固化效果逐渐增强。其原因为硅藻土对Sr2＋的吸附效果较好并能有效改善固化基体的微观结构。     

内皮细胞与小肠黏膜下层细胞相容性的初步研究

通过盐溶液溶胀和酶液消化制备小肠黏膜下层基质作为血管组织工程支架材料,将大鼠内皮细胞接种于支架材料上,测定小肠黏膜下层基质的细胞相容性.实验结果表明:内皮细胞在小肠黏膜下层基质上迅速铺展增殖生长,在4 h时大约有96%的细胞黏附于材料上,MTT法结果表明内皮细胞在支架上增殖生长明显,活细胞形态学观察表明细胞在支架材料上生长良好.     

纳米SrAl_2O_4:Eu~(2+),Dy~(3+)长余辉发光材料的制备与表征

采用甘氨酸-硝酸盐法(GNP)制备了SrAl2O4:Eu2+,Dy3+长余辉发光材料,研究了甘氨酸和金属离子的摩尔比(G/M)对Sr Al2O4:Eu2+,Dy3+长余辉发光材料结构与性能的影响.结果表明:随着G/M的增加,产物的晶粒尺寸和发射强度增大,发射光谱红移,而初始亮度呈现先增后减的规律;G/M为3∶1时,得到的产物为纯Sr Al2O4晶相,平均晶粒尺寸为75 nm,初始亮度最大;采用GNP合成的Sr Al2O4:Eu2+,Dy3+长余辉发光材料的发射光谱为宽谱带发光光谱,其发射主峰位为508 nm左右,是典型的Eu2+的4 f 5 d→4 f的特征发射。     

引导组织再生PDLLA/β-TCP膜的降解性能研究

聚DL－乳酸、β－磷酸钙（PDLLA／β－TCP）膜进行了体内外降解性能研究。体外将膜置于温度为37℃、pH＝7．4的缓冲溶液中,分2、4、8、12、16用取样,进行分子量测试及SEM观察．体内选取小鼠15只,将膜同期植入小鼠皮下,分别于2、4、8、12、16周处死小鼠,切取标本,常规制片,光镜下观察。本文认为：PDLLA／β－TCP具有良好的生物相容性、可降解性及骨结合能力,膜材还具有一定的硬度和韧性,是一种很有应用前景的GTR材料。     

锶掺杂羟基磷灰石-石墨烯复合材料制备与表征

锶(Sr)是人体含有的微量元素之一,研究锶掺杂羟基磷灰石复合物对于骨修复有重要意义.采用Ca(NO_3)_2·4H_2O溶液作为钙源,Na_2HPO_4作为磷源,加入适量Sr(NO_3)_2溶液以及石墨烯粉末,通过水热法合成锶掺杂羟基磷灰石-石墨烯(Sr-doped hydroxyapatite-grapheme,Sr-HA-GP)复合材料.利用傅里叶变换红外光谱仪、X射线衍射仪、场发射扫描电子显微镜、透射电子显微镜、X射线能量色散仪和拉曼光谱仪等,对该复合材料的表面形貌、物相组成和结构等进行表征和研究.结果表明,Sr~(2+)被成功掺入HA晶格中,低比例Sr~(2+)掺杂复合材料整体形貌较好,而高比例Sr~(2+)掺杂不仅会影响HA结晶度、改变其形貌、产生无定形相,而且会使HA颗粒出现团聚现象.同时,在水热过程中Sr-HA-GP复合材料的HA与GP界面间发生相互作用,各自结构都发生了变化.研究结果表明,Sr~(2+)掺杂量增加倾向于抑制HA微晶的生长,从而在石墨烯表面形成低结晶度的HA晶粒,而且Sr-HA与GP之间的复合并不是单纯的物理混合,而是发生了某种键合作用.     

磷酸钙沉淀在蔗糖溶液中吸附脱色规律的研究

在不同含量的蔗糖溶液中进行磷酸钙固相对焦糖、类黑素及葡萄糖碱性降解物吸附规律的实验研究发现,该固相吸附剂对这类色素的吸附特性属于Langmiur型,而且其对色素的吸附量与蔗糖含量呈现一定相关性．本文对蔗糖含量的影响进行了机理探讨,并利用现代计算机技术对磷酸钙固相在多组分液相中的等温吸附规律进行了数学描述．     

贵金属纳米粒子负载钛酸锶光催化剂

近年来, 钛酸锶作为一种新型光催化剂材料正逐渐成为研究热点。将银和钯纳米粒子按不同比例分别负载于钛酸锶粉体表面, 获得 M/SrTiO₃催化剂( M=Ag、Pd) 。结果表明, 银和钯纳米粒子均可以有效促进钛酸锶的光催化降解甲基橙的活性, 贵金属的种类和负载量均对催化剂活性具有明显的影响。Ag质量分数为0. 2%的催化剂活性最高, 2 h甲基橙降解率达到了95.1%, 相较于纯钛酸锶粉体, 降解率提高了大约35%。Pd质量分数为 0.2%的催化剂活性, 相较于纯钛酸锶粉体降解率提高了大约2 6%。对贵金属促进钛酸锶光催化活性的机理和影响规律进行了简单讨论。     

Biologically Inspired Self-assembling Synthesis of Bone-like Nano-hydroxyapatite/PLGA-(PEG-ASP)_n Composite: A New Biomimetic Bone Tissue Engineering Scaffold Material

1Introduction Replacementofbonetissuebygraftmaterialsand productsoftissueengineeringhavingcomposition,struc ture,andbiologicalfeaturesthatmimicnaturaltissueisa goaltobepursued[1].Poly(lacticacid)(PLA),poly(glycolicacid)(PGA),andtheircopolymers(PLGA)havebe…     

Synthesis,characterization and antibacterial property of strontium half and totally substituted hydroxyapatite nanoparticles

Nanoparticles of hydroxyapatite（HAP）, strontium half substituted hydroxyapatite （SrCaHAP） and strontium totally substituted hydroxyapatite （SrHAP） were prepared by sol-gel-supercritical fluid drying （SCFD） method. The nanoparticles were characterized by element content analysis, FT-IR, XRD and TEM, and the effects of strontium substitution on crystal structure, crystallinity, particle shape and antibacterial properties of the nanoparticles on Escherichia coli, Staphylococcus aureus, Lactobacillus were researched. Results show that strontium can half and totally substitute for calcium and enter the structure of apatite according to the initial atomic ratios of Sr/[Sr＋Ca] as 0.5, 1. The substitution decreases the IR wavenumbers of SrCaHAP and SrHAP, and changes the morphology of the nanoparticles from short rod shaped HAP to needle shaped SrCaHAP, and back to short rod shaped SrHAP. The crystallinity of HAP is higher than that of SrCaHAP, but is lower than that of SrHAP. Moreover, the antibacterial property of SrCaHAP and SrHAP are improved after the calcium is half and totally substituted by strontium.     

Synthesis,Charactcrization and Antibacterial Property of Strontium Half and Totally Substituted Hydroxyapatite Nanoparticles

Nanoparticles of hydroxyapatite(HAP),strontium half substituted hydroxyapatite(SrCaHAP) and strontium totally substituted hydroxyapatite(SrHAP)were prepared by sol-gel-supercritical fluid drying (SCFD) method.The nanoparticles were characterized by element content analysis,FT-IR,XRD and TEM,and the effects of strontium substitution on crystal structure.crystallinity,particle shape and antibacterial propemes of the nanoparticles on Escherichia coli,Staphylococcus aureus,Lactobacillus were researched.Results show that strontium can half and totally substitute for calcium and enter the structure of apatite according to the initial atomic ratios of Sr/[Sr+Ca] as 0.5,1.The substitution decreases the IR wavenumbers of SrCaHAP and SrHAP, and changes the morphology of the nanoparticles from short rod shaped HAP to needle shaped SrCaHAE and back to short rod shaped SrHAP.The crystallinity of HAP is higher than that of SrCaHAP, but is lower thall that of SrHAP.Moreove~the antibacterial property of SrCaHAP and SrHAP are improved after the calcium is half and totally substituted by strontium.     

Matrix metalloproteinase-sensitive poly(ethylene glycol)/peptide hydrogels as an interactive platform conducive to cell proliferation during 3D cell culture

The response of extracellular matrix(ECM) to dynamic cell signals is of great significance for the regulation of cell behavior. In the present study, we prepared a type of matrix metalloproteinase(MMP)-sensitive degradable hydrogels(MSDHs) via the catalyst-free o-phthalaldehyde(OPA)/amine cross-linking reaction between o-phthalaldehyde-grafted four-arm poly(ethylene glycol)(4aPEG-OPA) and an MMP-sensitive degradable peptide. The gelation rates and storage moduli of MSDHs and the MMP-insensitive hydrogels(MIHs) based on an MMP-insensitive scramble peptide were comparable and dependent on the concentrations of precursor polymers. MSDHs were degradable while MIHs were stable in the presence of proteinase in vitro.The degradation of MSDHs was obviously faster than that of MIHs after subcutaneous injection into rats. In addition, both types of poly(ethylene glycol)/peptide hydrogels displayed excellent cytocompatibility in vitro, and showed good histocompatibility in vivo in the subcutaneous layer of rats. Furthermore, the proliferation of several MMP-expressing cell lines including MDA-MB-231 cells within MSDHs was obviously faster than that in MIHs, indicating the influence of metabolism-mediated scaffold degradation on the cell proliferation. This study provides a new biocompatible and biodegradable 3 D cell culture interactive platform for regulation of cell behavior.     

不同质量比N,O-CMC/n-β-TCP复合材料在模拟体液中的降解性能

为评价不同质量比N,O-CMC/n-β-TCP复合材料在模拟体液中的降解性能。测定了不同降解时间模拟体液的pH值、钙、磷离子浓度、材料质量、表面结构及相成分变化以比较不同质量比复合材料的降解性能。结果表明:不同质量比复合材料降解液的pH值均在6.9以上,当二者质量比为1:1时,pH值处于7.0～7.4;复合材料的质量随降解时间呈增加趋势。XRD和FTIR分析表明,复合材料表面均有类骨羟基磷灰石生成,且以二者质比为1:1时生成量最多。     

Preliminary biocompatibility evaluation of regenerated <Emphasis Type="Italic">Antheraea yamamai</Emphasis> Silk Fibroin <Emphasis Type="Italic">in vitro</Emphasis>

The study aimed to investigate the adhesion, morphology and proliferation of Sprague Dawley (SD) albino rat bone marrow-derived mesenchymal stem cells (BMSCs) by inverted microscope, cell counting, MTT test and laser scanning confocal microscop (LSCM). On the regenerated A yamamai SF film or blend films, the cell morphology was almost the same as that on collagen (collagen type I) film, the cell adhesion rate was higher than that on plastic cell plate and B mori SF film after 1 h (p < 0.01) of culture, and the cell proliferation was significantly higher than that on collagen film (p < 0.01) and plastic cell plate (p < 0.01), and also obviously better than that on B mori SF film. On the other hand, the viability of BMSCs in the regenerated A yamamai SF porous scaffold was better than that in B mori SF porous scaffold and medical grade polyvinyl alcohol (PVA) sponge.