The precise design and fabrication of biomaterial scaffolds is necessary to provide a systematic study for bone tissue engineering. Biomaterial scaffolds should have sufficient stiffness and large porosity. These two ...The precise design and fabrication of biomaterial scaffolds is necessary to provide a systematic study for bone tissue engineering. Biomaterial scaffolds should have sufficient stiffness and large porosity. These two goals generally contradict since larger porosity results in lower mechanical properties. To seek the microstructure of maximum stiffness with the constraint of volume fraction by topology optimization method, algorithms and programs were built to obtain 2D and 3D optimized microstructure and then they were transferred to CAD models of STL format. Ti scaffolds with 30% volume fraction were fabricated using a selective laser melting （SLM） technology. The architecture and pore shape in the metallic biomaterial scaffolds were relatively precise reproduced and the minimum mean pore size was 231μm. The accurate fabrication of intricate microstructure has verified that the SLM process is suitable for fabrication of metallic biomaterial scaffolds.展开更多
Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurrin...Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurring tumors.Here we report that biodegradable magnesium(Mg)wirebased implant can inhibit OS growth.In brief,the Mg wires release Mg ions to activate the transport of zinc finger protein Snail1 from cytoplasm to cell nucleus,which induces apoptosis and inhibits proliferation of OS cells through a parallel antitumor signaling pathway of miRNA-181d-5p/TIMP3 and miRNA-181c-5p/NLK downstream.Simultaneously,the hydrogen gas evolution from Mg wires eliminates intracellular excessive reactive oxygen species,by which the growth of bone tumor cells is suppressed.The subcutaneous tumor-bearing experiment of OS cells in nude mice further confirms that Mg wires can effectively inhibit the growth of tumors and prolong the survival of tumor-bearing mice.In addition,Mg wires have no toxicity to normal cells and tissues.These results suggest that Mg implant is a potential anti-tumor scaffold for OS patients.展开更多
基金Project (51275179) supported by the National Natural Science Foundation of ChinaProject (2010A090200072) supported by Industry,University and Research Institute Combination of Ministry of Education, Ministry of Science and Technology and Guangdong Province,China+1 种基金Project (2012M511797) supported by China Postdoctoral Science FoundationProject (2012ZB0014) supported by FundamentalResearch Funds for the Central Universities of China
文摘The precise design and fabrication of biomaterial scaffolds is necessary to provide a systematic study for bone tissue engineering. Biomaterial scaffolds should have sufficient stiffness and large porosity. These two goals generally contradict since larger porosity results in lower mechanical properties. To seek the microstructure of maximum stiffness with the constraint of volume fraction by topology optimization method, algorithms and programs were built to obtain 2D and 3D optimized microstructure and then they were transferred to CAD models of STL format. Ti scaffolds with 30% volume fraction were fabricated using a selective laser melting （SLM） technology. The architecture and pore shape in the metallic biomaterial scaffolds were relatively precise reproduced and the minimum mean pore size was 231μm. The accurate fabrication of intricate microstructure has verified that the SLM process is suitable for fabrication of metallic biomaterial scaffolds.
基金the National Key Research and Development Program of China(2018YFC1106600)the Interdisciplinary Program of Shanghai Jiao Tong University(ZH2018QNB07)。
文摘Relapse and metastasis of tumor may occur for osteosarcoma(OS)patients after clinical resection.Conventional metallic scaffolds provide sufficient mechanical support to the defected bone but fail to eradicate recurring tumors.Here we report that biodegradable magnesium(Mg)wirebased implant can inhibit OS growth.In brief,the Mg wires release Mg ions to activate the transport of zinc finger protein Snail1 from cytoplasm to cell nucleus,which induces apoptosis and inhibits proliferation of OS cells through a parallel antitumor signaling pathway of miRNA-181d-5p/TIMP3 and miRNA-181c-5p/NLK downstream.Simultaneously,the hydrogen gas evolution from Mg wires eliminates intracellular excessive reactive oxygen species,by which the growth of bone tumor cells is suppressed.The subcutaneous tumor-bearing experiment of OS cells in nude mice further confirms that Mg wires can effectively inhibit the growth of tumors and prolong the survival of tumor-bearing mice.In addition,Mg wires have no toxicity to normal cells and tissues.These results suggest that Mg implant is a potential anti-tumor scaffold for OS patients.
