灌注法制备全肾脏脱细胞基质支架的体内生物相容性

背景：应用灌注法制备的大鼠全肾脏脱细胞基质支架具有良好的体外细胞相容性,但其体内生物相容性尚不明确。 目的：应用灌注法制备大鼠全肾脏脱细胞基质支架,检测其体内生物相容性。 方法：应用灌注法制备Wistar大鼠全肾脏脱细胞基质支架,进行以下实验：①急性毒性实验：在小鼠腹腔分别注射全肾脏脱细胞基质支架浸提液、生理盐水及苯酚。②溶血实验：将抗凝新西兰兔血分别与全肾脏脱细胞基质支架浸提液、生理盐水及蒸馏水混合。③热源实验：向新西兰兔耳缘静脉注射全肾脏脱细胞基质支架浸提液。④内皮刺激实验：在新西兰兔皮下注射全肾脏脱细胞基质支架浸提液,观察有无皮肤刺激反应。⑤皮下植入实验：将全肾脏脱细胞基质支架埋入新西兰兔背部皮下。 结果与结论：全灌注法制备的Wistar大鼠全肾脏脱细胞基质支架无细胞残留,未引起全身毒性反应、急性溶血反应、热源反应及皮肤刺激反应,植入兔体内具有良好的组织相容性。说明大鼠全肾脏脱细胞基质材料在动物体内具有很好的生物相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

壳聚糖/磷酸三钙复合组织工程支架材料的制备及其性能*

背景：通过适当的工艺混合、加工来制备复合支架材料,可以弥补单一材料的不足,最大限度地满足组织工程的需要。 目的：制备壳聚糖/磷酸三钙复合支架,探讨其作为牙髓组织工程支架材料的可行性。 方法：壳聚糖粉末溶于微量冰醋酸溶液中,搅拌均匀,静置脱泡,预冷冻,交联,再次冷冻制成海绵状多孔壳聚糖/磷酸三钙支架。 结果与结论：冻干法制备的壳聚糖/磷酸三钙多孔支架平均孔隙率达85.78%,最高孔隙率达90%以上,孔径在100~300 μm,复合后的支架材料具有良好的韧性,当轴向压缩变形量超过5 mm时,材料仍然没有发生破坏。材料浸提液与牙髓细胞复合培养后,细胞毒性均为0级,由此可见壳聚糖/磷酸三钙复合材料具有良好的生物相容性、细胞亲和性和一定的力学性能,满足生物材料基本要求。     

天然及合成尿道重建支架材料的生物相容性及力学性能

背景：目前应用何种尿道组织工程修复重建支架材料更为合适的争论仍不断出现,其生物相容性及力学特性的评估也鲜见报道。 目的：评估应用于尿道修复重建多种生物材料的力学特性及生物相容性。 方法：脱细胞法制备小肠黏膜下层组织、膀胱脱细胞基质以及脱细胞尿道海绵体基质,同时编织法制备聚乙醇酸支架。单轴拉伸测试测定各类支架生物力学特性,光镜及扫描电镜测定支架表面孔径大小。线粒体代谢活性MTT法检测各种生物材料的细胞毒性。所有支架表面接种海绵体平滑肌细胞,体外培养14 d后进一步评估细胞渗透情况。 结果与结论：生物力学评估显示脱细胞尿道海绵体基质在弹性模量以及断裂强度方面的检测结果明显优于其余材料(P < 0.05)。MTT结果显示所有支架材料均支持正常的细胞生长代谢,并未发现存在明显的细胞毒性。聚乙醇酸在扫描电镜中显示出最大的孔径(> 200 μm),同时脱细胞尿道海绵体基质的尿道面(< 5 μm)和海绵体面(>10 μm)观察到明显不同的孔径大小。细胞接种14 d后聚乙醇酸材料的内部可见种子细胞的广泛分布,在膀胱脱细胞基质以及脱细胞尿道海绵体基质的尿道面未发现有明显的细胞渗透迹象,而小肠黏膜下层组织和脱细胞尿道海绵体基质的海绵体面观察到明显的细胞渗透生长表现。提示所有支架材料显示出良好的生物相容性,同时在力学特性方面也与正常尿道组织相仿,但脱细胞尿道海绵体基质在力学和组织学的诸多参数上具有一定的优越性。     

兔肋软骨脱细胞基质的制备

背景：研究表明新西兰兔软骨组织可作为组织工程支架材料,其中关节软骨及耳软骨的脱细胞基质的研究较多,但采用肋软骨作为组织工程软骨支架的研究较少。 目的：制备新西兰兔肋软骨脱细胞基质,探讨天然软骨支架作为组织工程支架的可行性。 方法：用联合去垢剂-酶法获得软骨支架,根据脱细胞过程中Triton X-100第2次处理时间0,24,48,96 h分为4组。脱细胞完毕后各组支架固定行扫描电镜采集图像观察计算支架孔隙率、孔径长度,并对支架进行苏木精-伊红染色、甲苯胺蓝及Ⅱ型胶原免疫组织化学染色,并将脱细胞支架植入异体新西兰兔皮下观察其相容性。 结果与结论：兔肋软骨脱细胞基质呈乳白色,大小均一,染色示支架结构完整,仍保存大量酸性黏多糖及Ⅱ型胶原成分,扫描电镜观察经一定时间的脱细胞处理后可得到结构完整,孔隙均匀的天然软骨支架,其孔隙率为(61.31±8.45) %;孔径长度为(32.80±5.15) μm,符合正态性分布,各组脱细胞支架植入异体新西兰兔皮下7 d后生物相容性良好,周围软组织无明显充血、化脓等炎症排斥反应出现。结果显示,兔肋软骨脱细胞支架具有良好的基质组成,有较完整、均匀的孔隙结构及孔径分布,可作为组织工程支架材料。     

碳纤维-聚乳酸-聚乙二醇复合支架的制备及性能检测

背景：长期实验发现聚乳酸-聚乙二醇支架的力学性能及细胞相容性能较差,因此多数研究向支架中加入其他材料,以提高其生物活性及力学性能。 目的：制备改性碳纤维-聚乳酸-聚乙二醇支架,并检测其性能。 方法：采用溶液潘注/粒子沥滤法制备改性碳纤维-聚乳酸-聚乙二醇复合支架。对比改性碳纤维-聚乳酸-聚乙二醇复合支架与聚乳酸-聚乙二醇支架的超微结构、孔隙率、吸水性、降解率及力学性能。将改性碳纤维-聚乳酸-聚乙二醇复合支架与聚乳酸-聚乙二醇支架分别与SD大鼠成骨细胞共培养,12 h后采用沉淀法检测细胞黏附率;培养1,3,5,7,9 d后,采用 MTT 法检测细胞增殖。 结果与结论：聚乳酸-聚乙二醇支架材料表面孔结构分布均匀,孔径为(404.0±10.5) µm;改性碳纤维-聚乳酸-聚乙二醇支架碳纤维表面见大量纵向沟槽,表面孔结构分布均匀,孔径为(433.0±3.0) µm,两组支架孔径比较差异有显著性意义(P < 0.05)。改性碳纤维-聚乳酸-聚乙二醇支架的孔隙率、吸水性、弹性模量和抗压强度、降解率、细胞黏附率与增殖率均高于聚乳酸-聚乙二醇支架(P < 0.05)。表明改性碳纤维的加入改善了聚乳酸-聚乙二醇复合支架的力学性能及细胞相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

基于丝素/胶原/羟基磷灰石仿生骨材料的多维结构及其性能

目的 体外构建丝素蛋白（silk fibroin,SF）、I型胶原(type I collagen,Col-I)和羟基磷灰石(hydroxyapatite, HA)共混体系制备二维复合膜和三维仿生支架,研究其理化性质和生物相容性,探讨其在组织工程支架材料中应用的可行性。方法 通过在细胞培养小室底部共混SF/Col-I/HA以及低温3D打印结合真空冷冻干燥法制备二维复合膜及三维支架。通过机械性能测试、电子显微镜和Micro-CT检测材料的理化性质,检测细胞的增殖评估其生物相容性。结果 通过共混和低温3D打印获得稳定的二维复合膜及三维多孔结构支架;力学性能具有较好的一致性,孔径、吸水率、孔隙率和弹性模量均符合构建组织工程骨的要求;支架为网格状的白色立方体,内部孔隙连通性较好; HA均匀分布在复合膜中,细胞黏附在复合膜上,呈扁平状;细胞分布在支架孔壁周围,呈梭形状,生长及增殖良好。结论 利用SF/Col-I/HA共混体系成功制备复合膜及三维支架,具有较好的孔连通性与孔结构,有利于细胞和组织的生长以及营养输送,其理化性能以及生物相容性符合骨组织工程生物材料的要求。     

低温快速成型亲水改性复合人工骨支架的性能测定

背景：低温快速成型技术具有支架成型可控性、保持材料生物学活性和易于实现支架材料的三维多孔立体结构等优势,被迅速用于骨组织工程支架的制备。 目的：采用低温快速成型制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,并检测其性能。 方法：采用低温快速成型设备分别制备聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石与聚乳酸-乙醇酸/纳米羟基磷灰石复合支架,通过电镜观察支架超微结构,以介质(乙醇)浸泡法测定支架孔隙率,采用电子试验机检测支架力学性能;将两种支架材料分别与大鼠成骨细胞共培养,培养12 h采用沉淀法检测细胞黏附率,培养1,3,5,7,9,12 d采用CCK-8法检测细胞增殖。 结果与结论：两组支架孔径均在理想范围内并具有较高孔隙率,但聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的孔径波动范围大,孔径均值较聚乳酸-乙醇酸/纳米羟基磷灰石支架小且部分有闭塞现象。聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石支架的细胞黏附率及表面细胞增殖活性高于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P < 0.05),力学性能低于聚乳酸-乙醇酸/纳米羟基磷灰石支架(P < 0.05)。表明聚乙二醇改性聚乳酸-乙醇酸/纳米羟基磷灰石复合支架具有良好的细胞相容性。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程全文链接：     

运动性关节软骨缺损支架材料的选择及其生物相容性

背景：骨软骨支架是用于承载细胞,供细胞黏附、生长、增殖、分化的载体。 目的：总结运动性关节软骨缺损支架材料的应用进展及其生物替代材料的生物相容性。 方法：以“关节软骨,生物材料,工程软骨,支架材料,生物相容性”为中文关键词,以“ tissue enginneering ,articular cartilage,scaffold material”为英文关键词,采用计算机检索维普数据库、PubMed数据库1993-01/2010-11相关文章。纳入与有关修复关节软骨损伤、生物材料、支架材料、生物相容性等相关的文章。以20篇文献为重点对运动性关节软骨缺损修复用的生物材料的生物相容性进行了讨论。 结果与结论：天然软骨支架材料因其具有细胞识别信号,故生物相容性好,细胞黏附率高,但力学性能较差。有些人工合成材料生物相容性不理想、亲水性差、对细胞吸附不足,人工合成高分子聚合物生物相容性良好。复合支架利用不同生物材料的优点克制材料的局限性制备理想的复合支架,其混合比例、混合技术还有待进一步研究。目前尚无一种材料完全满足组织工程的要,通过材料制备技术的改进或将几种不同材料的复合,材料的性能会不断的提高。     

用于体外循环管材的新型醛基化海藻酸钠-地塞米松缓释涂层研究

研制新型醛基化海藻酸钠-地塞米松缓释涂层,筛选最佳涂层模式和涂层条件,对涂层稳定性、抗凝性能、缓释性能等进行评价。高碘酸钠氧化海藻酸钠得醛基化海藻酸钠（OSA）,酸化预处理聚氯乙烯（PVC）管材表面,聚乙烯亚胺涂抹经酸化预处理的PVC管材。聚乙烯亚胺涂层管材（PP）通过离子键直接交联地塞米松磷酸钠（DSP）制备DSP单涂层管材（PPD组）,PP通过离子键交联（PPI组）、共价键交联（PPC组）两种方式制备醛基化海藻酸钠-地塞米松磷酸钠复合涂层管材,同时设置空白对照（C组）。以正交实验筛选3种涂层模式的最佳涂层条件。对3种涂层管材进行涂层物定性和定量分析,抗凝、抗血小板、抗蛋白粘附、体外释放等性能进行评价研究,从而筛选最佳涂层模式。结果显示,PPD、PPI和PPC等3种涂层模式均能固定DSP,最佳固定密度分别为(333±075)、(163±076) 、(206±068)μg/cm2;复合涂层组（PPI和PPC）血小板粘附量（109/L）分别为（1388±189）和（1913±340）,均较C组（4138±320）显著减少;复合涂层组蛋白粘附量（mg/cm2）（HAS：（2986±1357）和（4667±320）,HPF：（3499±352）和（4567±379））,均较PPD组（HAS：（6873±426）,HPF：（7254±790））显著减少;体外释放方面PPC组明显优于PPI组。醛基化海藻酸钠-地塞米松复合涂层具备良好的血液相容性和生物相容性,通过共价交联的DSP能够达到缓释效果。     

脱细胞脊髓基质支架的制备及生物特性

背景：以脱细胞脊髓基质材料为构架的脊髓生物支架,已被证实可恢复或部分恢复受损的脊髓神经功能。 目的：介绍脱细胞脊髓基质支架的制备方法和部分生物特性,对近年来其在脊髓组织工程中的应用及进展作一概述。 方法：应用计算机检索 CNKI 和 PubMed 数据库中 2005年1月至2014年10月关于脱细胞脊髓基质支架材料在脊髓损伤中应用的文章,在主题和摘要中,中文以“脱细胞脊髓,支架材料,脊髓损伤,组织工程学”为检索词检索,英文以“acellular spinal cord;engineering tissue;spinal cord injury;scaffold”为检索词进行检索。 结果与结论：脱细胞脊髓基质支架具有较低的抗原性、优良的生物相容性及类似脊髓的三维支架结构,但存在力学性能差及结构不稳定等缺点。通过京尼平、戊二醛等交联剂改性后可明显提高支架的生物性能。目前国内外已对脱细胞脊髓基质支架在神经修复再生方面的应用做了一些探索,为脊髓组织工程学打下了基础。由于脱细胞脊髓基质支架的诸多优点,脱细胞脊髓基质材料有望成为脊髓组织工程学的理想材料。中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

生物组织超声弹性定征的进展

组织弹性或硬度的变化通常是与组织异常的病理状态相联系的 ,因此组织的弹性定征对于疾病诊断有着重要的意义。用超声进行组织弹性定征的方法有四种 :图像检查法、振动测量法、静态应变测量法和参数识别法。本文主要对振动测量法和静态应变测量法的基本原理和各种算法的发展进行了阐述 ,对超声弹性定征技术的现状、存在的问题和发展进行了分析。     

五种松质骨理化性质的比较

BACKGROUND: Existing evidence has shown that xenogeneic bone derived graft materials have the ability to repair bone defects, but little report is on the comparison of composition of xenogeneic bone and human bone. OBJECTIVE: To analyze the chemical composition, mineral phase, calcium and phosphorus contents, total protein contents, and appearance of the cancellous bones of the tibia from pig, bovine and human. METHODS:Cancellous bones of the tibia from pig, Banna miniature pig, bovine, young and old people were cut into bone particles of 0.5 cm×0.5 cm×0.5 cm. After degreasing or drying treatment, chemical composition, mineral phase, calcium and phosphorus contents, total protein contents of bone particles were detected using Fourier transform infrared spectroscopy, X-ray diffraction, plasma emission spectroscopy, scanning electron microscopy, and Kjeldahl method, respectively. Nano Measurer 1.2 and Photoshop cs6 were used to measure pore diameter and porosity rate based on the results of scanning electron microscope. RESULTS AND CONCLUSION: The main inorganic phase of five kinds of cancellous bones was hydroxyapatite and the main chemical composition was phosphate and carbonate. The calcium content of the bovine cancellous bonewas lower than that of the other cancellous bones (P < 0.05) and the phosphorus content of the cacellous bone of young man was higher than that of the pig and bovine cancellous bones (P < 0.01). The total protein content in the cancellous bones of normal pig and Banna miniature pig was higher than that in the other three kinds of cancellous bones (P < 0.05). The pore diameter of five kinds of cancellous bones was 400 to 600 μm and the porosity rate was 60% to 70%. Moreover, the porosity rate of the bovine cancellous bone was the highest. Therefore, we conclude that there are some certain differences in the organic and inorganic components of the pig or bovine cancellous bones as compared with humans. 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

可吸收生物材料在肌腱损伤重建中的防粘连作用

BACKGROUND: After sports tendon injury, tendon adhesion is the main reason for the failure to repair tendon injury. So, an ideal anti-adhesion material plays an important role in the tendon reconstruction.     

兔股动脉粥样硬化斑块模型中TF及TFPI的变化

目的： 观察兔股动脉粥样硬化斑块发展过程中斑块内组织因子（TF）及组织因子途经抑制物-1（TFPI-1）、组织因子途经抑制物-2（TFPI-2）的变化。方法： 新西兰雄兔通过高脂饲养合并股动脉球囊损伤建立动脉粥样硬化斑块模型。在建模8周、10周和12周，分别截取球囊损伤处股动脉标本，检测斑块组织内TF、TFPI-1和TFPI-2的蛋白表达；并测定斑块内TF、TFPI-1和TFPI-2的mRNA水平。结果： 自8周、10周到12周，血管斑块中TF、TFPI-1和TFPI-2的观测区域内阳性染色面积均逐渐增加。自8周、10周到12周，血管斑块中TF的mRNA水平和TFPI-1的mRNA水平均逐渐增加；TFPI-2mRNA表现为前期无明显变化，12周时显著下调。结论： 在兔股动脉粥样硬化斑块的形成过程中，随着斑块内TF基因及蛋白表达的增加,TFPI-1和TFPI-2反应性表达增加，但其表达水平未能完全抑制斑块的进展。     

组织损伤修复中的生物力学问题

生物力学对损伤组织修复的影响及调控研究方兴未艾。组织修复与再生医学的发展为生物力学的研究提供了新平台,而生物力学则成为推动组织修复与再生医学发展的重要因素。对《医用生物力学》2016年第5期发表的"生物力学与组织修复"专栏论文进行简要的分析、述评,同时对该领域的研究进行回顾和展望。     

Tissue-driven Hypothesis with Gene Ontology (GO) Analysis

Most of the genes are under selective pressure to maintain their expression levels in the tissues. In a recent study, we have proposed a “tissue-driven” hypothesis stating that the stabilizing constraints on gene expression levels can be partitioned among tissues; tissues differ in their tolerance to gene expression variances; and the constraints on expression divergence is correlated with the constraints on sequence divergence. Here we further tested the “tissue-driven” hypothesis by sub-grouping genes into Gene Ontology (GO) categories. We examined the distribution of tissue expression distance of genes in the major GO categories in the tissues. We also examined the correlation between tissue expression distances and tissue sequence distances or tissue duplicate distances in the major GO categories. Our results have shown that the tissues-specific stabilizing constraints are generally not dominated by particular GO categories. It is also shown that sub-grouping genes into GO categories increased the sensitivity for detecting potential positive factors in expression divergence in the tissues. Zhixi Su and Yong Huang contributed equally to this work.     

磷酸钙骨水泥/纤维蛋白胶复合材料填充桡骨缺损的生物相容性

BACKGROUND: The chemical compositions and structure of calcium phosphate bone cement are similar to those of human bone, which can fill the bone collapse caused by fracture and induce osteogenesis, but its degradation rate is slow. OBJECTIVE: To evaluate the biocompatibility of the calcium phosphate cement/fibrin glue and the feasibility of repairing radius defects. METHODS: In vitro cytotoxicity experiment: Mouse fibroblasts were cultured in the calcium phosphate bone cement/fibrin glue extracts, phenol solution, and RPMI 1640 culture medium containing 10% fetal bovine serum, respectively, to detect the cytotoxicity grade. Hemocompatibility experiment: Calcium phosphate bone cement/fibrin glue extracts, normal saline and distilled water were respectively added into the rabbit anticoagulation, to detect the hemolytic rate. Forty-five New Zealand white rabbits were enrolled and modeled into bilateral radius defects, followed by randomly allotted into three groups: blank control group without any intervention, experimental and control groups were given the implantation with calcium phosphate bone cement/fibrin glue and autologous radius, respectively. X-ray, histology, bone mineral density and biomechanical test were performed at postoperative 4, 8 and 16 weeks. RESULTS AND CONCLUSION: The toxicity grade of the calcium phosphate cement/fibrin glue was 0 to 1. The hemolytic rate of the calcium phosphate cement/fibrin glue was 3.15%. At 16 weeks postoperatively, X-ray showed that in the experimental and control groups, the fracture line disappeared completely, pulp cavity was recanalized, and in plastic completely. Histology showed that the reconstructed bone trabecular was obvious, plate layer of bone was mature, and medullary cavity recanalization appeared in the control group; there were a large number of new grid-shaped woven bone tissues growing into the material in the experimental group, with overt degradation, and degradation rate was in parallel to bone ingrowth. The bone density, the maximum load, maximum stress and failure energy in the experimental and control groups were significantly higher than those in the blank control group (P < 0.05), and all above indicators showed no significant differences between the experimental and control groups. These results manifest that the calcium phosphate bone cement/fiber protein glue composite material holding a good biocompatibility can promote bone tissue regeneration for bone defect repair, achieving similar curative effect with autologous bone transplantation.     

脱细胞羊膜与医用膜修复腱鞘缺损防治肌腱粘连的比较

BACKGROUND: Experiments have demonstrated that biological membranes can be used to reconstruct the tendon sheath and inhibit exogenous healing of the tendon. Therefore, these membranes provide a good bed for tendon gliding and reduce tendon adhesion.     

A Fully Automated Approach to Quantitatively Determine Thickness of Tissue-Engineered Cell Sheets

Sheet-based tissue engineering is an innovative field that has provided the scientific community with new tissue-engineered products such as skin, cornea, heart valves, and vascular grafts. As this area of tissue engineering progresses toward clinical implementation, quality control becomes more and more important. Imaging methods advertise themselves because of their high resolution and good tissue-fluid contrast. We present and compare two methods, one based on a custom-designed automatized large-area confocal scanner that uses backscattered light for image formation, and one based on optical coherence tomography (OCT). In both modalities, additional image processing is used to extract sheet thickness and density information and to create a quantitative tissue thickness map in a fully automated fashion. In test objects (glass of known thickness and scattering samples) and engineered tissue sheets with artificially introduced defects we found high agreement between the two methods in the measurement of thickness and the visual representation of the defects. Both the OCT and the confocal scanner were able to provide high-detail images visually consistent to those obtained with brightfield microscopy. Both OCT and large-area confocal scanning in combination with specialized image processing algorithms promise to provide information on tissue homogeneity, density, and the presence of potential defects in tissue sheets in an unsupervised fashion and thus help establish new quality control methods in sheet-based tissue engineering. Jeffrey T. LaCroix and Jinjun Xia share credit for first authorship.