多孔陶瓷材料的制备技术及应用

本文综述了近年来多孔陶瓷材料制备技术的研究现状及应用，多孔陶瓷性能特殊，应用广泛，并为生物医学等相关行业带来进步。     

纳米羟基磷灰石对肝癌细胞端粒酶基因表达的影响

研究羟基磷灰石（HAP）纳米粒子对Bel-7402人肝癌细胞端粒酶基因表达的影响。采用均相沉淀法制备出稳定单分散的HAP纳米粒子,应用透射电镜、电位粒度仪对其进行表征。HAP纳米粒子作用Bel-7402肝癌细胞4 h后,采用原位杂交技术检测Bel-7402肝癌细胞的端粒酶基因表达。结果表明HAP纳米粒子作用组的Bel-7402肝癌细胞的端粒酶阳性细胞比例为61.38%,而对照组的端粒酶阳性细胞比例为87.89%,2组有显著性差异（P〈0.01）。HAP纳米粒子可使Bel-7402肝癌细胞的端粒酶基因表达下调。     

羟基磷灰石纳米粒子对肝癌细胞PCNA表达的影响

为了研究羟基磷灰石(HAP)纳米粒子对肝癌细胞增殖细胞核抗原表达的影响,采用均匀沉淀法制备了均匀分散的纳米尺度的HAP纳米粒子。以0.56 mmol/L的HAP纳米粒子与Bel-7402肝癌细胞作用后,采用流式细胞技术检测细胞周期时相的变化,行免疫细胞化学法PCNA染色,形态学观察和定量分析细胞的PCNA表达。结果显示HAP纳米粒子能使Bel-7402细胞的细胞增殖周期阻滞于G1期,PCNA表达降低,与对照组比较有显著性差异(P<0.01)。HAP纳米粒子可能通过抑制PCNA的表达,起到抑制肝癌细胞增殖的作用。     

Effect of Apatite Nanoparticles on DNA and AgNOR of Bel-7402 Hepatocellular Carcinoma

1Introduction IthavebeenfoundthatApatitenanoparticlescanin hibitproliferationofhumanhepatocellularcarcinomacells invitro.Tofurtherinvestigateapatitenanoparticlesinhib itingproliferationofhumanhepatocellularcarcinomacells invitro,twosignificantbiologicalpa…     

羟基磷灰石纳米粒子对肝癌增殖活性的影响

为了研究HAP纳米粒子对肝癌细胞的增殖能力及生物学行为的影响，采用均匀沉淀法制备了均匀分散的纳米尺度的HAP纳米粒子。以0．56mmol/的HAP纳米粒子与Bel-7402肝癌细胞作用4d后，细胞行Feulgen染色和AgNOR染色，显微镜观察标本、图像分析系统定量分析肝癌细胞的DNA和AgNOR。结果显示HAP纳米粒子能降低Bel-7402细胞的DNA含量，减少细胞的AgNOR数量，与对照纽比较均有显著性差异（P〈0．01）。HAP纳米粒子能减弱肝癌细胞的增殖活性，可能是通过抑制DNA的合成，以及减少AgNOR数量而抑制rRNA的合成，发挥抗癌作用。     

A New Type of Nanogel Carrier based on Mixed Pluronic Loaded with Low-Dose Antitumor Drugs

To design a new type of antitumor nanodrug carrier with good biocompatibility, a drug delivery system with a 2.19% drug-loading rate, measured by high-performance liquid chromatography(HPLC), was prepared by membrane hydration using a mixed polymer: Pluronic~? F-127, which binds folic acid(FA), Pluronic~? F-68 and triptolide(TPL)(FA-F-127/F-68-TPL). As a control, another drug delivery system based on a single polymer(FA-F-127-TPL) with a 1.90% drug-loading rate was prepared by substituting F-68 with F-127. The average particle sizes of FA-F-127/F-68-TPL and FA-F-127-TPL measured by a particle size analyzer were 30.7 nm and 31.6 nm, respectively. Their morphology was observed by atomic force microscopy(AFM). The results showed that FA-F-127-TPL self-assembled into nanomicelles, whereas FA-F-127/F-68-TPL self-assembled into nanogels. An MTT assay showed that a very low concentration of FA-F-127/F-68-TPL or FA-F-127-TPL could significantly inhibit the proliferation of multidrug-resistant(MDR) breast cancer cells(MCF-7/ADR cells) and induce cell death. The effects were significantly different from those of free TPL(P 0.01). Using the fluorescent probe Nile red(Nr) as the drug model, FA-F-127/F-68-Nr nanogels and FAF-127-Nr nanomicelles were prepared and then incubated with human hepatocarcinoma(HepG2) and MCF-7/ADR cells, and the fluorescence intensity in the cells was measured by a multifunctional microplate reader. The results indicated that both FA-F-127/F-68-Nr and FA-F-127-Nr had sustained release in the cells, but HepG2 and MCF-7/ADR cells exhibited significantly higher endocytosis of FA-F-127/F-68-Nr than that of FA-F-127-Nr(P 0.01). A nude mice transplanted tumor model was prepared to monitor FA-F-127/F-68-Nr in the tumor tissue and organs by whole-body fluorescent imaging. The results showed that FA-F-127/F-68-Nr targeted tumor tissues. The prepared nanogels had small particle size, were easy to swallow, exhibited slow release property,targeted tumor cells, and could improve the antitumor effects of TPL; hence, they are ideal carriers for low-dose antineoplastic drugs.     

兔成骨细胞体外培养体系的研究

为了建立兔成骨细胞体外培养模型，为骨替代材料的研究提供成骨细胞，选用了新生15d兔颅盖骨，采用酶消化法和组织块法相结合的方法进行成骨细胞的体外分离和培养，通过倒置显微镜观察其形态，并对其碱性磷酸酶（ALP）活性及矿化能力进行鉴定，结果显示培养细胞具有体内成骨细胞的形态学特征和生物学行为。体外培养兔成骨细胞的实验方法切实可行，成功建立了兔成骨细胞体外培养模型，为骨替代材料的实验研究提供了一种客观而有效的手段。     

Effects of the interaction between hydroxyapatite nanoparticles and hepatoma cells

To gain a better understanding of the anticancer effects of hydroxyapatite(HAP) nanoparticles in vivo and in vitro, the effects of the interaction of HAP nanoparticles with hepatoma cells were explored. HAP nanoparticles were prepared by homogeneous precipitation and characterized by laser particle analysis and transmission electron microscopy(TEM). HAP nanoparticles were observed to be uniformly distributed, with rod-like shapes and diameters in the range of 42.1-87.1 nm. Overnight attached, suspended, and proliferating Bel-7402 cells were incubated with HAP nanoparticles. Inverted microscopy observation revealed that HAP nanoparticles with a cell membrane showed good adsorption. TEM demonstrated that HAP nanoparticles were present on the surface of cells, continuously taken up by cells through endocytosis, and transported in vesicles close to the nucleus. Fluorescence microscopy showed that the concentrations of intracellular Ca2+ labeled with Fluo-3 calcium fluorescent probe were significantly enhanced. In addition, inverted microscopy observation revealed that suspended cells treated with HAP nanoparticles did not adhere to the culture bottle, resulting in cell death. After the overnight attached cells were treated with HAP nanoparticles for 96 h with increasing doses of HAP nanoparticles, inverted microscopy observation revealed that cell proliferation was slowed and cell–cell adhesion was weakened. Feulgen staining and image analysis indicated that the nuclear DNA content of the cells was markedly reduced, and argyrophilic nucleolar organizer region(AgNOR) staining and image analysis indicated that the number of AgNORs was signifi cantly decreased. Therefore, hepatoma cells brought about the adsorption, uptake, transport and degradation of HAP nanoparticles. In addition, HAP nanoparticles affected hepatoma cells with regard to cell–cell adhesion, cell and extracellular matrix adhesion, and DNA and protein synthesis; thus inhibiting cell proliferation. This understanding of the effects of interaction between HAP nanoparticles and hepatoma cells is useful for further study of the anticancer mechanisms of HAP nanoparticles.