生长因子缓释系统复合纳米支架材料修复犬下颌骨缺损*

背景:支架材料联合细胞因子构建组织工程骨不受血管化和细胞培养因素的限制,这种构建模式可能诱导出较大体积的实用型组织工程骨.目的:观察壳聚糖纳米微球/纳米羟基磷灰石/聚乳酸-羟基乙酸复合生长因子缓释支架修复犬下颌骨临界骨缺损的能力.方法:取杂种犬12条,制作双侧下颌骨临界骨缺损模型,一侧植入复合生长因子骨形态发生蛋白2、转化生长因子β1及血管内皮生长因子165的壳聚糖纳米微球/纳米羟基磷灰石/聚乳酸-羟基乙酸缓释支架(实验组),另一侧植入壳聚糖纳米微球/纳米羟基磷灰石/聚乳酸-羟基乙酸缓释支架(对照组),术后4,8,12周取下颌骨标本行X 射线、组织学及免疫组织化学检查.结果与结论:实验组术后不同时间点X射线灰度值及骨钙素积分吸光度值均高于对照组(P <0.05),表明复合生长因子的支架材料修复骨缺损的成骨能力优于未复合生长因子的支架材料.组织学观察结果显示,实验组术后不同时间点成骨时间及效果均优于对照组,表明复合生长因子骨形态发生蛋白2、转化生长因子β1及血管内皮生长因子165的壳聚糖纳米微球/纳米羟基磷灰石/聚乳酸-羟基乙酸缓释支架可更快更有效地促进骨缺损修复.     

可注射骨修复材料结合骨碎补总黄酮修复大鼠颅骨缺损

背景：自体髂骨移植一直被认为是骨缺损修复的“金标准”,但其来源有限。目的：验证应用可注射骨修复材料结合骨碎补总黄酮修复大鼠颅骨缺损的效果。方法：80只雄性SD大鼠建立双侧颅骨缺损模型,随机分为3组：骨修复材料＋骨碎补总黄酮组采用可注射骨修复材料结合骨碎补总黄酮灌胃修复大鼠颅骨缺损：骨修复材料＋去离子水组采用可注射骨修复材料结合去离子水灌胃修复大鼠颅骨缺损;羟基磷灰石＋去离子水组采用羟基磷灰石结合去离子水灌胃修复大鼠颅骨缺损,1次／d,持续8周。于建模后2,4,8周取颅骨标本进行苏木精一伊红染色和Masson染色组织学观察。结果与结论：羟基磷灰石组新骨形成和材料降解速度较慢;可注射骨修复材料组新骨形成和材料降解较羟基磷灰石组快,利于血管及纤维组织长入;骨碎补总黄酮灌胃可以促进血管及纤维组织长入材料,促进成骨。与羟基磷灰石相比,可注射骨修复材料结合骨碎补总黄酮修复大鼠颅骨缺损,可促进新骨形成,缩短骨缺损修复时间。     

含镧羟基磷灰石的合成和性能研究

目的：研究湿法合成含镧式磷灰石的可行性及其体外生物活性。方法：采用湿法合成羟基磷磷石和两种不同的含羟基磷灰石粉,在３００℃、６００℃、９００℃热处理。红外光谱及Ｘ线衍射分析粉的成分。将９００℃热处理的两种含羟基磷灰石及羟基磷灰石的压片在模拟体液内浸泡,采用扫描电镜及溶液钙离子浓度测定法观察其体外生物活性,结果：通过热处理可去除含镧羟基磷灰石及羟基磷灰石内的杂质成分,获得的羟基磷灰石。含镧羟基磷灰石     

儿童羟基磷灰石眼座眶内植入对眼眶发育的影响研究

From１９９５to２００１，５３anophthalmicchildrenhavebeenperformedorbitplastywithhydroxyapatiteplantwrappedupwithscleralorduramatershell，andallpatientshavegotsatisfactoryeffects．Theresultsarereportedasfollowing．１Subjectsandmethods１．１MaterialsAgroupof５３patients（aged２～１２averaged６．１，２９maleand２４female）wereafterenucleationofeyeball．Thecauseofenucleationincluded：variantocularinjuryfor３８cases，absoluteglaucomaandendophthalmitisfor６cases，con－genitalmicrophthalmiafor６case…     

Adsorption of the Tartrate Ions in the Hydroxyapatite/Aqueous Solution of NaCl System

The research on the interaction of tartrate ions with the surface of hydroskyapatite was presented, including the measurements of the kinetics of tartrate ion adsorption and tartrate ion adsorption as a function of pH. The adsorption of tartrate ions was calculated from the loss of tartrate concentration in the solution as measured by a radioisotope method using C-14 labeled tartaric acid. In order to explain the mechanism of interaction of tartrate ions with hydroxyapatite, supplementary measurements were carried out, i.e., potentiometric measurements of the balance of released/consumed ions in the hydroxyapatite/electrolyte solution system, zeta potential measurements, FTIR spectrophotometric measurements and the hydroxyapatite crystal structure and particle size distribution were characterized. It was found that the adsorption of tartrate ions occurs as a result of the exchange of these ions with hydroxyl, phosphate and carbonate ions. Replacing the ions with the abovementioned tartrate ions leads to the appearance of a negative charge on the surface of the hydroxapatite. On the basis of XRD study and particle size distribution, a decrease in the size of crystallites and the diameter of hydroxyapatite particles in contact with a solution of 0.001 mol/dm³ of tartaric acid was found.     

Preparation,Characterization, and Biocompatibility Assessment of Polymer-Ceramic Composites Loaded with Salvia officinalis Extract

In the present work, hydroxyapatite-polymer materials were developed. The preparation, as well as characterization of the ceramic-polymer composites based on polyvinylpyrrolidone, sodium alginate, and gelatin were described. The system was enriched with the addition of common sage extract (Salvia officinalis). The antioxidant potential of sage aqueous extract and total polyphenol content was determined. The antioxidant capacity and total phenolic content of extract were equal to 86.06 ± 0.49% and 16.21 ± 0.58 mg gallic acid equivalents per gram of dry weight, respectively. Incubation studies in selected biological liquids were carried out to determine the biomineralization capacity on the surface of the composites and to examine the kinetics of release of the active substances from within the material. As a result of the incubation, a gradual release of the extract over time from the polymer matrix was observed; moreover, the appearance of new apatite layers on the composite surface was recorded as early as after 14 days, which was also confirmed by energy-dispersive X-ray spectroscopy (EDS) microanalysis. The composites were analyzed with Fourier transform infrared spectroscopy (FTIR) spectroscopy, and the morphology was recorded by scanning electron microscope (SEM) imaging. The in vitro biological studies allowed their cytotoxic effect on the reference L929 fibroblasts to be excluded. Further analysis of the biomaterials showed that enrichment with polyphenols does not support the adhesion of L929 cells to the surface of the material. However, the addition of these natural components stimulates human monocytes that constitute the first step of tissue regeneration.