电化学共沉积制备有机高聚物/钙磷复合陶瓷膜层-Ⅰ XRD、SEM表征及生物活性研究

首次提出在NH4H2PO4－Ca(NO3)2溶液中添加溶性乙烯类有机高聚物，实现了通过电化学共沉积法制备具有生物活性的有机高聚物／钙磷陶瓷复合膜层。用XRD、SEM等对膜层的组分和形貌进行表征，证明陶瓷膜层表面形貌发生明显的变化。有机高聚物的引入，并不影响电沉积制备的羟基磷灰石（HAP）晶体在（002）晶面生长存在的晶面择优取向，体外细胞实验表明，HAP／有机高聚物复合膜层具有优良的生物活性。     

锶掺杂改性羟基磷灰石的生物学性能研究

目的：研究不同锶掺杂量的羟基磷灰石Sr-HA的生物相容性及生物学活性。方法：合成0%(A)、1%(B)、5%(C)、10%(D)、20%(E)掺锶含量不同的五组Sr-HA,检测各组试样浸提液中钙、锶离子浓度,通过溶血试验检测了五组材料体外溶血性。L929成纤维细胞材料表面接种培养2、5天,通过倒置相差显微镜观察细胞形态MTT法检测相对增值度测试五组材料体外细胞毒性。将MG63成骨细胞接种到五种材料表面,采用MTT方法检测1、4、12小时成骨细胞在材料表面的附着和1、4、7 d时细胞在材料表面的增殖情况;并对第1、3、5天成骨细胞ALP活性进行检测。结果：100%浸提液五组材料中Ca₂₊浓度5%(C)最高,1%(B)最低;Sr₂₊浓度,20%(E)最高,0%(A)组最低。各组掺锶羟基磷灰石组的溶血率均低于5%。显微镜观察L929细胞的形态与阴性对照组比较相似。MTT检测相对增殖度5组材料总体毒性评级为0级、1级。MG63成骨细胞在材料表面培养4、12小时, 5%(C)、10%(D)、20%(E)三组表面细胞粘附数量明显高于0%(A)、1%(B)组 (P<0.05,P<0.01);12小时：1%(B)细胞粘附数量高于0%(A)组(P<0.05)。MG63成骨细胞在材料表面培养4、7天,5%(C)、10%(D)、20%(E)三组表面细胞增殖数量明显高于0%(A)、1%(B)组 (P<0.05,)。ALP活性检查显示：3天时5%(C)、10%(D)两组ALP活性高于其它三组(P<0.05,)。5天时5%(C)、10%(D)、20%(E)三组ALP活性高于0%(A)、1%(B)两组(P<0.05,)。结论：不同锶含量掺杂的羟基磷灰石具有良好地生物相容性,一定浓度的锶离子掺杂能够有效的提高羟基磷灰石的生物学活性,我们认为5%(C)、10%(D)组掺杂Sr-HA生物学效果最佳。     

Formation and adhesion of biomimetic hydroxyapatite deposited on titanium substrates

This study has been carried out to investigate the bioactivity of rutile and to deposit hydroxyapatite (HA) on heat-treated titanium through a biomimetic method. Biomimetic deposition of HA has gained large interest because of its low deposition temperature and good step coverage; however, it demands a substrate with bioactive properties. Commercially pure titanium is not bioactive but it can acquire bioactive properties through various surface treatments. In the present study, titanium plates were heat-treated at 800 °C to achieve rutile TiO₂ surfaces. These samples were immersed in a phosphate-buffered saline solution for seven days in order to deposit a HA layer on the surface. The rutile TiO₂ surfaces were found to be highly bioactive: after seven days of immersion, a layer of HA several micrometers thick covered the plates. The HA surfaces were confirmed by electron microscopy and X-ray diffraction. A scratch test was used to assess the adhesion of the HA coatings. This is a standard method to provide a measure of the coating-to-substrate adhesion and was found to be a useful method to test the thin HA coatings deposited on the bioactive surfaces. The critical pressure of the layer was estimated to be 2.4 ± 0.1 GPa.     

Self-setting properties and in vitro bioactivity of calcium sulfate hemihydrate-tricalcium silicate composite bone cements

Self-setting biomaterials are widely used for tissue repair and regeneration. Calcium sulfate hemihydrate has been used for many years as a self-setting biomaterial due to its good setting properties. However, too fast a degradation rate and lack of bioactivity have limited its application in orthopaedic field. Herein, tricalcium silicate was introduced into calcium sulfate hemihydrate (CaSO₄ · 1/2H₂O) to form a calcium sulfate hemihydrate-based composite, and its behavior as a cement was studied in comparison with pure calcium sulfate hemihydrate. The results indicated that the workability and setting time of the composite pastes are higher than those of pure CaSO₄ · 1/2H₂O, and the composite pastes showed much better short- and long-term mechanical properties than those of pure CaSO₄ · 1/2H₂O. Moreover, the biphasic specimens showed significantly improved bioactivity and degradability compared with those of pure CaSO₄ · 1/2H₂O, indicating that the composite cements might have a significant clinical advantage over the traditional CaSO₄ · 1/2H₂O cement.     

脑源性神经营养因子前体的研究进展

神经营养因子是一种分泌性多肽类生长因子家族,参与神经系统的多种生理功能活动,研究发现成熟的脑源性神经营养因子与其前体分子具有不同的生物学活性,它们的受体以及介导的细胞内信号通路也大相径庭。本文对近年来关于脑源性神经营养因子前体分子的研究进展予以综述,着重讨论其体内分布、生物合成与分泌、生物学活性以及与疾病的联系。研究脑源性神经营养因子前体分子在生理和病理状态下的作用将对未来的药物开发和神经系统疾病的治疗具有重要的意义。     

冻干前后红细胞血型及生物活性指标的检测

目的检测冻干前、后红细胞血型抗原及其生物学活性,了解冻干前、后红细胞血型抗原及其生物学活性的变化情况。方法红细胞血型抗原的检测采用血型血清学方法,2,3-DPG和ATP用ELISA法。结果在ABO、Rh、MNSs、Kell、Duffy、P血型抗原中,冷冻前、冻干后红细胞血型抗原一致;在Lewis血型抗原中,冷冻前、冻干后红细胞血型抗原有变化。冷冻前、冻干后红细胞2,3-DPG和ATP含量均无明显变化。结论冷冻前、冻干后红细胞Lewis血型系统中的Lea和Leb血型抗原变化有明显差异;冷冻前、冻干后红细胞2,3-DPG和ATP含量变化无统计学意义。     

Cytotoxic and bioactive properties of different color tulip flowers and degradation kinetic of tulip flower anthocyanins

This study was conducted to determine the potential use of anthocyanin-based extracts (ABEs) of wasted tulip flowers as food/drug colorants. For this aim, wasted tulip flowers were samples and analyzed for their bioactive properties and cytotoxicity. Total phenolic contents of the extracts of the claret red (126.55 mg of gallic acid equivalent (GAE)/g dry extract) and orange–red (113.76 mg GAE/g dry extract) flowers were the higher than those of the other tulip flowers. Total anthocyanin levels of the violet, orange–red, claret red and pink tulip flower extracts were determined as 265.04, 236.49, 839.08 and 404.45 mg pelargonidin 3-glucoside/kg dry extract, respectively and these levels were higher than those of the other flowers. The extracts were more effective for the inhibition of Listeria monocytogenes, Staphylococcus aureus and Yersinia enterocolitica compared to other tested bacteria. Additionally, the cytotoxic effects of five different tulip flower extracts on human breast adenocarcinoma (MCF-7) cell line were investigated. The results showed that the orange red, pink and violet extracts had no cytotoxic activity against MCF-7 cell lines while yellow and claret red extracts appeared to be toxic for the cells. Overall, the extracts of tulip flowers with different colors possess remarkable bioactive and cytotoxic properties.     

突变前后天花粉蛋白的生物活性及免疫原性比较研究

目的：对天花粉蛋白（Trichosanthin，TCS）进行定点突变，比较其与野生型TCS（wTCS）间的生物活性及免疫原性差异。方法：选择TCS分子上可能的抗原决定簇位点（YFF81—83和KR173—174）进行定点突变，并将所构建的突变体（TCSYFF-KR）在大肠杆菌中表达及纯化。随后将其与wTCS比较，分析其DNA酶活性、致核糖体失活活性和免疫原性。结果：构建的突变体TCSYFF-KR其活性与wTCS活性几乎相当，而免疫原性有所降低。结论：通过该方法改造TCS是可行的，所构建的突变体TCSYFF-KR值得进一步研究。     

中药内生真菌的生物活性物质及其多组学研究进展

摘要：近年来,植物内生真菌已成为发现活性先导化合物的重要源泉之一,它也是替代植物次级代谢产物有潜力的新药用资源。以中药来源的植物内生真菌为例,其次级代谢产物具有广泛的生物活性,如抗肿瘤、抗炎、抗菌等药理作用。真菌独特的遗传与代谢多样性对新天然药物的发现具有重要的研究价值。因此,本文综述了近10年来中药来源内生真菌的活性次级代谢产物,以及多组学技术在内生真菌研究中的进展,为中药来源内生真菌的开发及应用提供借鉴。