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Hybrid polycaprolactone/hydrogel scaffold fabrication and in-process plasma treatment using PABS 预览
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作者 Fengyuan Liu Hussein Mishbak Paulo Bartolo 《国际生物打印期刊》 2019年第1期24-32,共9页
A challenge for tissue engineering is to produce synthetic scaffolds of adequate chemical,physical,and biological cues effectively.Due to the hydrophobicity of the commonly used synthetic polymers,the printed scaffold... A challenge for tissue engineering is to produce synthetic scaffolds of adequate chemical,physical,and biological cues effectively.Due to the hydrophobicity of the commonly used synthetic polymers,the printed scaffolds are limited in cell-seeding and proliferation efficiency.Furthermore,non-uniform cell distribution along the scaffolds with rare cell attachment in the core region is a common problem.There are no available commercial systems able to produce multi-type material and gradient scaffolds which could mimic the nature tissues.This paper describes a plasma-assisted bio-extrusion system(PABS)to overcome the above limitations and capable of producing functional-gradient scaffolds;it comprises pressure-assisted and screw-assisted extruders and plasma jets.A hybrid scaffold consisting of synthetic biopolymer and natural hybrid hydrogel alginate-gelatin(Alg-Gel)methacrylate anhydride,and full-layer N2 plasma modification scaffolds were produced using PABS.Water contact angle and in vitro biological tests confirm that the plasma modification alters the hydrophilicity properties of synthetic polymers and promotes proliferation of cells,leading to homogeneous cell colonization.The results confirm the printing capability for soft hard material integration of PABS and suggest that it is promising for producing functional gradient scaffolds of biomaterials. 展开更多
关键词 Tissue engineering hybrid scaffold PABS in-process plasma modification functional gradient scaffold
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Generate basic conceptual solutions for 3DPVS via utilizing TRIZ 预览
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作者 Haobo Yuan Ke Xing Hung-Yao Hsu 《生物设计与制造(英文)》 CSCD 2019年第2期76-95,共20页
For cell culture scaffold innovation,3DPVS,namely 3D printed vibratory scaffold,was indicated as a future novel product,and it currently stands at conceptual development stage.One essential part for 3DPVS design is in... For cell culture scaffold innovation,3DPVS,namely 3D printed vibratory scaffold,was indicated as a future novel product,and it currently stands at conceptual development stage.One essential part for 3DPVS design is innovation,and TRIZ(algorithm of inventive problem solving)was studied as promising method for generating novel conceptual solutions.This study targets designing and solving 3DPVS problems using TRIZ in the new biodimension.We aim to utilize TRIZ to conduct a multi-layer problem-solving process,which is to address design concerns of 3DPVS,especially at super-system to system level.In this connection,TRIZ is used to address basic constraints and contradictions inside regarding trinity of 3D printing,3D scaffold and bio-based vibratory functionality.In the study,five basic conceptual solutions for potential 3DPVS,namely magnetic,electric,mechanical,light and thermal based,have been generated.A brief evaluation has also been conducted,where magnetic-based 3DPVS shows the relatively highest applicability as potential 3DPVS.Compared with traditional experimental-oriented processes for biodesign,the approach of utilizing TRIZ can be inspiring and reinvigorating,which prepares a ground for future 3DPVS design to address detailed sub-system concerns.This study might,to some extent,fill a gap in scaffold design and TRIZ literature and hopefully provide a comprehensive perspective of a timely topic. 展开更多
关键词 3DPVS 3D SCAFFOLD 3D PRINTING SCAFFOLD INNOVATION Biodesign TRIZ CONCEPT generation
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Development of a Powder Extruder System for Dual-pore Tissue-engineering Scaffold Fabrication
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作者 Nae-Un Kang Myoung Wha Hong +2 位作者 Young Yul Kim Young-Sam Cho Seung-Jae Lee 《仿生工程学报:英文版》 SCIE EI CSCD 2019年第4期686-695,共10页
In this study,we developed a powder extruder system that can extrude and deposit powder mixtures to overcome the reported limitations of conventional dualpore scaffold manufacturing methods.To evaluate the extrusion a... In this study,we developed a powder extruder system that can extrude and deposit powder mixtures to overcome the reported limitations of conventional dualpore scaffold manufacturing methods.To evaluate the extrusion and deposition capability of the powder extruder system,3D tissue-engineering scaffolds with dual-pore characteristics were fabricated with a PCL/PEO/NaCl(polycaprolactone/polyethylene oxide/sodium chloride)powder mixture.In addition,to evaluate the fabricated scaffolds,their compressive modulus,morphology,and in-vitro cell activity were assessed.Consequently,it was confirmed that the proposed powder extruder system can fabricate dual-pore scaffolds with well-interconnected pores as well as arbitrary 3D shapes shown by the fabrication of a 3D femur-shape scaffold similar to the femur model.The results of the cell proliferation and Cell Counting Kit-8(CCK-8)assays,DNA content analysis and viability assays confirm that the dual-pore scaffold fabricated by the powder extruder system improves cell attachment,proliferation,and viability. 展开更多
关键词 dual-pore SCAFFOLD POWDER EXTRUDER system polycaprolactone 3D TISSUE-ENGINEERING SCAFFOLD
体外三维细胞培养系统的研究进展 预览
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作者 郭凯宁 陈纯 《海峡药学》 2019年第5期1-4,共4页
细胞生长依赖细胞微环境,细胞外基质是细胞微环境的重要组分,不仅为细胞提供了支持、居住环境,同时通过膜受体而影响细胞的黏附、迁移、增殖、分化、存活等生物行为。目前广泛应用的体外二维细胞培养与细胞的体内生长状态差别较大,三维... 细胞生长依赖细胞微环境,细胞外基质是细胞微环境的重要组分,不仅为细胞提供了支持、居住环境,同时通过膜受体而影响细胞的黏附、迁移、增殖、分化、存活等生物行为。目前广泛应用的体外二维细胞培养与细胞的体内生长状态差别较大,三维细胞培养是利用三维结构的细胞外基质模拟体内环境,使细胞在近似体内环境中生长。三维培养中涉及诸多影响因素,如细胞外基质的组成、支架结构、硬度及微流控芯片调控营养物质供应及代谢。本文对国内外该领域的研究进行综述整理并提出展望。 展开更多
关键词 细胞外基质 三维细胞培养 支架 硬度 微流控芯片
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Fabrication and Characterization of Nanopillar-Like HA Coating on Porous Ti6AI4V Scaffold by a Combination of Alkali-Acid-Heat and Hydrothermal Treatments
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作者 Jun-Lei Li Shuai Wang +7 位作者 Fang Cao Xiao Lin Xiao-Wei Wei Zhen-Hua Zhao Xiao-Jie Dou Wei-Ting Yu Ke Yang De-Wei Zhao 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第9期1075-1088,共14页
Porous titanium scaffold with suitable porous architecture exhibits enormous potentials for bone defect repairs.However,insufficient osteointegration and osteoinduction still remain to open as one of the major problem... Porous titanium scaffold with suitable porous architecture exhibits enormous potentials for bone defect repairs.However,insufficient osteointegration and osteoinduction still remain to open as one of the major problems to achieve satisfactory therapeutic effect.To solve this problem,many studies have been carried out to improve the bioactivity of porous titanium scaff old by surface modifications.In this study,porous Ti6Al4V scaff olds were fabricated using additive manufacturing technique.Porous architectures were built up based on a diamond pore structure unit.Alkali–acid-heat(AH)treatment was applied to create a TiO2 layer on the porous Ti6Al4V scaff old(AH-porous Ti6Al4V).Subsequently,a hydrothermal treatment was employed to enable the formation of HA coating with nanopillar-like morphology on the alkali–acid-heat-treated surface(HT/AH-porous Ti6Al4V).The effects of surface modifications on apatite-forming ability,protein adsorption,cell attachment,cell proliferation and osteogenic gene expression were studied using apatite-forming ability test,protein adsorption assay and in vitro cell culture assay.It was found that the HT/AH-porous Ti6Al4V exhibited the highest apatite formation ability and best affinity to fibronectin and vitronectin.In vitro studies indicated that the mesenchymal stem cells(MSCs)cultured on the HT/AH-porous Ti6Al4V presented improved adhesion and differentiation compared with the porous Ti6Al4V and AH-porous Ti6Al4V. 展开更多
关键词 ADDITIVE manufacturing BIOMATERIALS POROUS titanium SCAFFOLD HA coating
Near-field electrospinning of a polymer/bioactive glass composite to fabricate 3D biomimetic structures 预览
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作者 Krishna C.R.Kolan Jie Li +4 位作者 Sonya Roberts Julie A.Semon Jonghyun Park Delbert E.Day Ming C.Leu 《国际生物打印期刊》 2019年第1期14-19,共6页
Bioactive glasses have recently gained attention in tissue engineering and three-dimensional(3D)bioprinting because of their ability to enhance angiogenesis.Some challenges for developing biological tissues with bioac... Bioactive glasses have recently gained attention in tissue engineering and three-dimensional(3D)bioprinting because of their ability to enhance angiogenesis.Some challenges for developing biological tissues with bioactive glasses include incorporation of glass particles and achieving a 3D architecture mimicking natural tissues.In this study,we investigate the fabrication of scaffolds with a polymer/bioactive glass composite using near-field electrospinning(NFES).An overall controlled 3D scaffold with pores,containing random fibers,is created and aimed to provide superior cell proliferation.Highly angiogenic borate bioactive glass(13-93B3)in 20 wt.%is added to polycaprolactone(PCL)to fabricate scaffolds using the NFES technique.Scaffolds measuring 5 mm×5 mm×0.2 mm^3 in overall dimensions were seeded with human adipose-derived mesenchymal stem cells to investigate the cell viability.The cell viability on PCL and PCL+glass scaffolds fabricated using NFES technique and 3D printing is compared and discussed.The results indicated higher cell proliferation on 3D biomimetic scaffolds fabricated by NFES technique. 展开更多
关键词 Near-field electrospinning three-dimensional biomimetic scaffold POLYCAPROLACTONE polymer/bioactive glass composite borate bioactive glass human adipose-derived stem cells
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Chitosan tubes enriched with fresh skeletal muscle fibers for delayed repair of peripheral nerve defects 预览
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作者 Alessandro Crosio Benedetta Elena Fornasari +5 位作者 Giovanna Gambarotta Stefano Geuna Stefania Raimondo Bruno Battiston Pierluigi Tos Giulia Ronchi 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期1079-1084,共6页
Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump... Nerve regeneration after delayed nerve repair is often unsuccessful.Indeed,the expression of genes associated with regeneration,including neurotrophic and gliotrophic factors,is drastically reduced in the distal stump of chronically transected nerves;moreover,Schwann cells undergo atrophy,losing their ability to sustain regeneration.In the present study,to provide a three-dimensional environment and trophic factors supporting Schwann cell activity and axon re-growth,we combined the use of an effective conduit(a chitosan tube)with a promising intraluminal structure(fresh longitudinal skeletal muscle fibers).This enriched conduit was used to repair a 10-mm rat median nerve gap after 3-month delay and functional and morphometrical analyses were performed 4 months after nerve reconstruction.Our data show that the enriched chitosan conduit is as effective as the hollow chitosan conduit in promoting nerve regeneration,and its efficacy is not statistically different from the autograft,considered the“gold standard”technique for nerve reconstruction.Since hollow tubes not always lead to good results after long defects(>20 mm),we believe that the conduit enriched with fresh muscle fibers could be a promising strategy to repair longer gaps,as muscle fibers create a favorable three-dimensional environment and release trophic factors.All procedures were approved by the Bioethical Committee of the University of Torino and by the Italian Ministry of Health(approval number:864/2016/PR)on September 14,2016. 展开更多
关键词 tubulization Schwann cells SCAFFOLD tissue engineering NERVE reconstruction morphometrical analyses GRASPING test secondary repair MEDIAN NERVE NERVE REGENERATION
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Laser additive manufacturing of Zn porous scaffolds;Shielding gas flow, surface quality and densification
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作者 Peng Wen Yu Qin +4 位作者 Yanzhe Chen Maximilian Voshage Lucas Jauer Reinhart Poprawe Johannes Henrich Schleifenbaum 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第2期368-376,共9页
Zn based metals have exhibited promising prospects as a structural material for biodegradable applications. Pure Zn porous scaffolds were produced by laser powder bed fusion(LPBF) based on data files of designing and ... Zn based metals have exhibited promising prospects as a structural material for biodegradable applications. Pure Zn porous scaffolds were produced by laser powder bed fusion(LPBF) based on data files of designing and CT scanning. Massive Zn evaporation during laser melting largely influenced the formation quality during LPBF of Zn metal. The metal vapor in processing chamber was blown off and suctioned out efficiently by an optimized gas circulation system. Numerical analysis was used to design and testify the performance of gas flow. The surface of scaffolds was covered with numerous particles in different sizes. Processing pores occurred near the outline contour of struts. The average grain size in width was8.5m, and the hardness was 43.8 HV. Chemical plus electrochemical polishing obtained uniform and smooth surface without processing pores, but the diameter of struts reduced to 250 αm from the design value 300 m. The poor surface quality and processing pores were resulted by the splashing particles included spatters and powders due to the recoil force of evaporation, and the horizontal movement of liquid metal due to overheating and wetting. The insufficient melting at the outline contour combined with good wetting of Zn liquid metal further increased the surface roughness and processing pores. 展开更多
关键词 ADDITIVE manufacturing Powder bed fusion LASER Porous SCAFFOLD ZN
软骨脱细胞基质仿生支架体外构建组织工程软骨 预览
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作者 贾立涛 姚琳 +4 位作者 刘延群 张沛灵 刘豫 曹谊林 周广东 《组织工程与重建外科》 2019年第4期222-226,244共6页
目的探索软骨脱细胞基质(ACM)仿生支架体外构建组织工程软骨的可行性。方法将软骨组织彻底粉碎后脱细胞处理,复合一定比例的明胶(GT)制备三维多孔支架。分析比较不同ACM/GT比例多孔支架的孔径、孔隙率、生物力学和降解速率,选取最适宜... 目的探索软骨脱细胞基质(ACM)仿生支架体外构建组织工程软骨的可行性。方法将软骨组织彻底粉碎后脱细胞处理,复合一定比例的明胶(GT)制备三维多孔支架。分析比较不同ACM/GT比例多孔支架的孔径、孔隙率、生物力学和降解速率,选取最适宜软骨体外再生的一组多孔支架用于体外构建。获取、培养猪关节软骨细胞,接种于ACM多孔支架上,体外培养8周后,行大体观察及组织学检测。结果ACM多孔支架孔隙分布均匀,随ACM含量的增加,孔径和孔隙率逐渐增大,力学强度逐渐降低,其中,ACM:GT=5:5组在孔径和孔隙率方面均适宜体外软骨再生。大体观察和组织学检测显示,ACM支架可体外再生均质、典型的软骨组织。结论ACM可制成适宜软骨再生的三维多孔支架,并可体外构建组织工程软骨。 展开更多
关键词 软骨脱细胞基质 明胶 支架材料 软骨再生 组织工程软骨
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Surface texture evaluation of additively manufactured metallic cellular scaffolds for acetabular implants using X.ray computed tomography 预览
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作者 Shan Lou Luca Pagani +3 位作者 Wenhan Zeng Muhammad U.Ghori Xiangqian Jiang Paul J.Scott 《生物设计与制造(英文)》 CSCD 2019年第2期55-64,共10页
The surface topography of acetabular implants plays a key role in providing cell attachment and proliferation.The measurement and characterisation of the surface texture of the cellular scaffold layer on the acetabula... The surface topography of acetabular implants plays a key role in providing cell attachment and proliferation.The measurement and characterisation of the surface texture of the cellular scaffold layer on the acetabular cup are very difficult due to the 3D nature of scaffold geometry.It is proposed to use X-ray computed tomography(XCT)to measure the surface texture of an electron beam melting-produced titanium acetabular cup.The surface texture of its cellular scaffold is evaluated using the newly developed 3D surface texture parameters,which allows surface characterisation on 3D triangular mesh surfaces.Four commonly used height parameters,i.e.the arithmetical mean height Sa,the root mean square height Sq,the skewness Ssk and the kurtosis Sku,are calculated from surface patches extracted from the XCT scanned triangular mesh surface.In addition,the surface peak density and pit density,which are more related to cell communication and proliferation,are estimated based on the 3D watershed segmentation.The Wolf pruning with an empirical threshold 12μm is used to control the over-segmentation. 展开更多
关键词 ADDITIVE manufacturing CELLULAR SCAFFOLD Surface TEXTURE X-ray COMPUTED tomography
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鼓膜组织工程学研究进展 预览
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作者 黎欢 胡益 +2 位作者 姚旭 吴淋蓉 沈毅 《中国现代医生》 2019年第8期164-168,共5页
鼓膜穿孔是耳鼻喉科常见的临床症状,慢性鼓膜穿孔治疗主要通过手术修补,各种自体移植材料常被作为移植物来修补穿孔鼓膜。近年来,鼓膜再生领域的研究逐渐趋向于应用组织工程学治疗技术。许多新型组织工程材料在鼓膜修复中体现出良好的... 鼓膜穿孔是耳鼻喉科常见的临床症状,慢性鼓膜穿孔治疗主要通过手术修补,各种自体移植材料常被作为移植物来修补穿孔鼓膜。近年来,鼓膜再生领域的研究逐渐趋向于应用组织工程学治疗技术。许多新型组织工程材料在鼓膜修复中体现出良好的鼓膜再生和听力重建效果。然而,组织工程鼓膜的制作需要考虑多种因素。本综述通过总结概括目前在鼓膜穿孔修复中所使用的支架材料、生物活性分子和细胞来阐述鼓膜再生的组织工程学研究进展。 展开更多
关键词 鼓膜穿孔 组织工程学 支架 生物活性分子
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连墙件设置缺陷对脚手架立杆最大弯矩的影响 预览
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作者 秦桂娟 刘国文 《沈阳建筑大学学报:自然科学版》 CAS CSCD 北大核心 2019年第1期109-116,共8页
目的研究风荷载作用下连墙件设置缺陷对脚手架立杆最大弯矩的影响程度和规律,为脚手架合理设计提供依据.方法考虑高层建筑施工脚手架风振影响计算出风载荷标准值,对扣件节点采用半刚性研究,利用有限元ANSYS分析软件对脚手架架体进行模... 目的研究风荷载作用下连墙件设置缺陷对脚手架立杆最大弯矩的影响程度和规律,为脚手架合理设计提供依据.方法考虑高层建筑施工脚手架风振影响计算出风载荷标准值,对扣件节点采用半刚性研究,利用有限元ANSYS分析软件对脚手架架体进行模拟分析,研究连墙件设置缺陷下架体立杆最大弯矩的变化及规律.结果从模拟分析中得出连墙件设置方式不同时脚手架立杆最大弯矩的变化趋势和结果,对比分析后得出当连墙件只与内立杆连接时,最大弯矩主要出现在有连墙件立杆节点处,其立杆最大弯矩增加,连墙件设置缺陷对脚手架立杆最大弯矩的影响程度可达近一倍.结论当连墙件设置只与内立杆相连时,对立杆弯矩增加较大,降低其承载力,在施工过程中脚手架连墙件设置应该保证与内外立杆同时连接. 展开更多
关键词 脚手架 立杆 连墙件 风荷载 最大弯矩
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丝素蛋白-壳聚糖支架复合骨髓间充质干细胞体内构建组织工程化软骨的生物相容性 预览
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作者 佘荣峰 张一 +3 位作者 陈龙 王远政 张彬 黄琪翔 《中国组织工程研究》 CAS 北大核心 2020年第1期27-32,共6页
背景:课题组前期的研究中发现,丝素蛋白-壳聚糖支架材料复合诱导后骨髓间充质干细胞在兔体内能修复缺损的软骨组织,但对于该组织工程化软骨组织的生物相容性还未进一步研究。目的:研究丝素蛋白-壳聚糖支架材料复合骨髓间充质干细胞在体... 背景:课题组前期的研究中发现,丝素蛋白-壳聚糖支架材料复合诱导后骨髓间充质干细胞在兔体内能修复缺损的软骨组织,但对于该组织工程化软骨组织的生物相容性还未进一步研究。目的:研究丝素蛋白-壳聚糖支架材料复合骨髓间充质干细胞在体内构建组织工程化软骨的生物相容性。方法:使用丝素蛋白-壳聚糖按1∶1比例混合制备三维支架材料,提取兔骨髓间充质干细胞,将诱导后的骨髓间充质干细胞与丝素蛋白-壳聚糖支架构建修复体,再将修复体移植到兔关节软骨缺损模型中修复软骨组织。实验分为3组,实验组植入诱导后骨髓间充质干细胞+丝素蛋白-壳聚糖支架,对照组植入丝素蛋白-壳聚糖支架干预,空白组未植入修复体。结果与结论:①实验成功制备丝素蛋白-壳聚糖三维支架材料及提取骨髓间充质干细胞,并构建软骨缺损的修复体,将修复体植入兔体内能成功修复缺损的软骨组织;②建模后2,4,8,12周,3组血常规、降钙素原、血沉、C-反应蛋白结果提示无明显的全身感染征象,3组血常规及肝肾功能各时间段比较差异无显著性意义(P>0.05);③一般观察、苏木精-伊红染色及扫描电镜观察:建模后12周,相比其他两组,实验组软骨缺损已修复,支架材料已吸收,修复组织周围未见炎性细胞,修复组织已正常组织整合良好;④结果证实,丝素蛋白-壳聚糖支架复合骨髓间充质干细胞在体内构建的组织工程化软骨具有良好的生物相容性。 展开更多
关键词 丝素蛋白 壳聚糖 骨髓间充质干细胞 组织工程 生物相容性 支架材料 种植体 软骨缺损 软骨修复 体内实验
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水凝胶支架材料在牙髓再生中的研究进展 预览
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作者 夏鹍 张旗 《口腔医学》 CAS 2019年第7期651-654,659共5页
近年来用于牙髓再生的支架材料逐渐被重视,并成为研究热点。其中水凝胶凭借一定的韧性、流变性、良好的生物相容性和可降解性等优势,被越来越广泛地应用于牙髓再生的研究中。水凝胶在调控干细胞命运、调节生长因子释放、装载抗菌抗炎药... 近年来用于牙髓再生的支架材料逐渐被重视,并成为研究热点。其中水凝胶凭借一定的韧性、流变性、良好的生物相容性和可降解性等优势,被越来越广泛地应用于牙髓再生的研究中。水凝胶在调控干细胞命运、调节生长因子释放、装载抗菌抗炎药物等方面都发挥着重要作用。该文就水凝胶支架材料在牙髓再生中的研究进展作一综述。 展开更多
关键词 牙髓再生 支架材料 水凝胶 干细胞 生长因子 药物
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再生医学之组织工程耳廓软骨再生与功能重建
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作者 李雪盛 孙建军(审校) 《临床耳鼻咽喉头颈外科杂志》 CAS 北大核心 2019年第6期567-571,共5页
对于人类来说,耳廓收集声波的功能意义远低于其外观价值,因此,耳廓外形或位置的任何异常都是难以接受的。耳廓组织缺损的常见原因包括四类:先天畸形、炎症、外伤或手术(医源性)。支撑耳廓外形的软骨属于弹力软骨,维持着耳廓独特的外形... 对于人类来说,耳廓收集声波的功能意义远低于其外观价值,因此,耳廓外形或位置的任何异常都是难以接受的。耳廓组织缺损的常见原因包括四类:先天畸形、炎症、外伤或手术(医源性)。支撑耳廓外形的软骨属于弹力软骨,维持着耳廓独特的外形与功能,相对于软骨表面的皮肤组织,软骨再生能力弱,而且来源有限,因此耳廓缺损重建的重点在于如何恢复其弹性软骨支架。另外,与其他部位的软骨修复不同,耳廓软骨重建不仅要考虑其功能,而且对外观的要求更高。 展开更多
关键词 软骨组织工程 耳廓重建 软骨细胞培养 支架
非降解聚氨酯弹性体支架材料体外构建残耳软骨用于修复耳廓组织的可行性 预览
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作者 刘戈 杨庆华 +2 位作者 张玲 韩景健 董维玮 《中国美容医学》 CAS 2019年第3期89-92,共4页
目的:探讨以非降解聚氨酯弹性体支架材料体外构建残耳软骨用于修复耳廓组织的可行性。方法:分离30例临床小儿畸形患者软骨细胞,经培养、扩增后制成细胞悬液滴加于圆盘状聚氨酯支架上,体外培养21d后接种于裸鼠体内培养42d,应用扫描电镜... 目的:探讨以非降解聚氨酯弹性体支架材料体外构建残耳软骨用于修复耳廓组织的可行性。方法:分离30例临床小儿畸形患者软骨细胞,经培养、扩增后制成细胞悬液滴加于圆盘状聚氨酯支架上,体外培养21d后接种于裸鼠体内培养42d,应用扫描电镜观察细胞-支架复合物生长情况,同时使用免疫组织化学法观察成软骨细胞冰冻切片情况。结果:软骨细胞体外培养3周后形成的细胞-支架复合物的形态学及组织学较正常耳廓软骨组织相差甚远,而在裸鼠体内培养6周的细胞-支架复合物外观光滑细腻,与正常耳廓软骨组织相近,经免疫组织化学法分析可见新生的软骨组织细胞间质中存在蓝黑色的丝网状弹力纤维。结论:聚氨酯材料能够成为组织工程耳廓软骨的支架材料,且体内培养较体外培养更利于软骨组织的生长。 展开更多
关键词 非降解聚氨酯弹性体 组织工程 支架 培养 耳软骨损伤 修复
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Enantioselective Intramolecular Desymmetric ct-Addition of Cyclohexa- none to Propiolamide Catalyzed by Sodium L-Prolinate
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作者 Bao-Le Li Wei-Yang Gao +6 位作者 Han Li Shuo-qing Zhang Xiao-qing Han Jun Lu Ren-Xiao Liang Xin Hong Yi-Xia Jia 《中国化学:英文版》 SCIE CAS CSCD 2019年第1期63-70,共8页
Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization reaction.By employing simple and ... Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization reaction.By employing simple and readily available L-proline sodium salt as a bifunctional catalyst,a series of chiral 6,6-bicyclic bridged products bearing morphan scaffold have been isolated in good yields and excellent enantioselectivities.Density functional theory (DFT)calculations elucidated the origins of the enantioselectivity and regioselectivity of this transformation.A salt bridge that links the amide carbonyl group with proline carboxylate in the transition state was proven to be the driving force for the induction of excellent enantioselectivity. 展开更多
关键词 ENANTIOSELECTIVE SCAFFOLD group
胶原静电纺纳米纤维膜对人牙髓细胞生物学行为的影响 预览
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作者 张倩莉 袁重阳 +2 位作者 刘力 温世鹏 王晓燕 《北京大学学报:医学版》 CAS CSCD 北大核心 2019年第1期28-34,共7页
目的:比较人牙髓细胞(human dental pulp cells,hDPCs)在胶原静电纺纳米纤维膜(collagen nanofibrous matrix,Col_NFM)与直接沉积胶原膜(collagen flat film,Col_FF)上的黏附、增殖和分化情况,探究胶原纳米纤维支架对hDPCs生物学行为的... 目的:比较人牙髓细胞(human dental pulp cells,hDPCs)在胶原静电纺纳米纤维膜(collagen nanofibrous matrix,Col_NFM)与直接沉积胶原膜(collagen flat film,Col_FF)上的黏附、增殖和分化情况,探究胶原纳米纤维支架对hDPCs生物学行为的影响。方法:采用扫描电镜(scanning electron microscopy, SEM)观察两种胶原膜的表面形貌,并比较其表面接触角和溶胀性能。将hDPCs分别接种于两种胶原膜表面共培养,SEM和激光共聚焦显微镜(laser scanning microscope,LSM)观察hDPCs在支架表面的生长形态,并用CCK-8法测定hDPCs的增殖情况。在诱导14 d后,比较成牙本质分化相关基因的表达变化,茜素红染色观察矿化结节的形成情况。结果:SEM图可见Col_NFM组纤维直径为(884±159) nm,纤维之间存在大量三维连通的孔隙结构,而Col_FF组表面平坦,未见孔隙结构。Col_NFM组瞬间表面接触角为85.03°±4.45°,溶胀度为3,Col_FF组瞬间表面接触角为98.98°±5.81°,溶胀度为1,Col_NFM组的亲水性和溶胀性能更佳。SEM和LSM结果显示,Col_NFM组hDPCs表现为不规则多角形,呈三维生长,Col_FF组细胞在二维平面上呈纺锤形生长。CCK-8结果显示,hDPCs在Col_NFM支架上增殖活性更高。在诱导14 d后,Col_NFM组成牙本质分化相关基因表达水平较Col_FF组显著升高(P<0.05),茜素红染色也更深。结论:Col_NFM具有纳米尺度的微观结构,并具备良好的亲水性和溶胀性能,相较于Col_FF,hDPCs在Col_NFM表面表现出更好的黏附、增殖和分化性能。 展开更多
关键词 胶原 静电纺丝 牙髓再生 纳米纤维 支架
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探析连续梁桥悬臂现浇施工技术的运用 预览
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作者 郝晓勇 《山西建筑》 2019年第16期135-136,共2页
针对某高速公路连续梁桥实际情况,在介绍悬臂浇筑前重要工序,挂篮操作的基础上,对其悬臂浇筑施工技术具体运用进行深入分析,阐述了施工工艺原理和各环节需要注意的要点,并通过实践验证了该工程所用悬臂现浇施工技术的合理性与可行性,为... 针对某高速公路连续梁桥实际情况,在介绍悬臂浇筑前重要工序,挂篮操作的基础上,对其悬臂浇筑施工技术具体运用进行深入分析,阐述了施工工艺原理和各环节需要注意的要点,并通过实践验证了该工程所用悬臂现浇施工技术的合理性与可行性,为类似工程提供参考依据。 展开更多
关键词 连续梁桥 悬臂现浇施工技术 挂篮
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人关节软骨细胞外基质来源组织工程支架的制备和评估 预览
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作者 彭礼庆 罗旭江 +6 位作者 张彬 沈师 黄波 高超 鲁晓波 刘舒云 郭全义 《中国组织工程研究》 CAS 北大核心 2019年第34期5436-5441,共6页
背景:软骨细胞外基质作为一种天然材料,为依赖组织生长的细胞提供了理想的微环境,已成为一种理想的软骨修复支架材料。目的:将人关节软骨来源的细胞外基质制备成软骨组织工程支架,评价其理化性质及生物学性能。方法:收集人源性关节软骨... 背景:软骨细胞外基质作为一种天然材料,为依赖组织生长的细胞提供了理想的微环境,已成为一种理想的软骨修复支架材料。目的:将人关节软骨来源的细胞外基质制备成软骨组织工程支架,评价其理化性质及生物学性能。方法:收集人源性关节软骨组织,予粉碎成匀浆、去细胞处理、冷冻干燥法制备成软骨组织工程支架。观察:①扫描电镜观察支架形态;②支架的孔隙率、吸水率测定,测量支架力学性质;③支架的成分:使用组织化学和免疫组织化学法染色观察;④支架细胞毒性:用人软骨细胞外基质支架浸提液与常规细胞培养液做对比,培养兔软骨细胞不同时间后使用MTT比色法检测;⑤细胞黏附及增殖情况:使用扫描电镜及共聚焦显微镜观察人软骨细胞与支架共培养后细胞黏附增殖情况,支架细胞复合体切片染色观察。结果与结论:①制备而成的支架呈三维多孔海绵状纵行取向形态,支架孔隙周围有软骨纤维,支架苏木精-伊红染色未见细胞核、番红O及天狼星红染色均证实支架含有胶原和软骨基质成分;②支架的孔隙率为(91.8±2.9)%、吸水率为(93.5±1.4)%;③人软骨细胞外基质支架浸提液经MTT检测,对软骨无细胞毒性;④共培养后,人软骨细胞在支架孔隙周壁上黏附、增殖且分布均匀。结果表明,人软骨细胞外基质多孔取向支架的成分与天然软骨近似,结构可供细胞均匀黏附、增殖良好,组织相容性好,可作为一种组织工程修复软骨缺损的支架材料。 展开更多
关键词 组织工程 细胞外基质 支架 软骨 同种异体
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