Blood loss by hemorrhaging wounds accounts for over one-third of~5 million trauma fatalities worldwide every year.If not controlled in a timely manner,exsanguination can take lives within a few minutes.Developing new ...Blood loss by hemorrhaging wounds accounts for over one-third of~5 million trauma fatalities worldwide every year.If not controlled in a timely manner,exsanguination can take lives within a few minutes.Developing new biomaterials that are easy to use by non-expert patients and promote rapid blood coagulation is an unmet medical need.Here,biocompatible,and biodegradable microneedle arrays(MNAs)based on gelatin methacryloyl(GelMA)biomaterial hybridized with silicate nanoplatelets(SNs)are developed for hemorrhage control.The SNs render the MNAs hemostatic,while the needle-shaped structure increases the contact area with blood,synergistically accelerating the clotting time from 11.5 min to 1.3 min in vitro.The engineered MNAs reduce bleeding by~92%compared with the untreated injury group in a rat liver bleeding model.SN-containing MNAs outperform the hemostatic effect of needle-free patches and a commercial hemostat in vivo via combining micro-and nanoengineered features.Furthermore,the tissue adhesive properties and mechanical interlocking support the suitability of MNAs for wound closure applications.These hemostatic MNAs may enable rapid hemorrhage control,particularly for patients in developing countries or remote areas with limited or no immediate access to hospitals.展开更多
Metal additive manufacturing(AM)has led to an evolution in the design and fabrication of hard tissue substitutes,enabling personalized implants to address each patient’s specific needs.In addition,internal pore archi...Metal additive manufacturing(AM)has led to an evolution in the design and fabrication of hard tissue substitutes,enabling personalized implants to address each patient’s specific needs.In addition,internal pore architectures integrated within additively manufactured scaffolds,have provided an opportunity to further develop and engineer functional implants for better tissue integration,and long-term durability.In this review,the latest advances in different aspects of the design and manufacturing of additively manufactured metallic biomaterials are highlighted.After introducing metal AM processes,biocompatible metals adapted for integration with AM machines are presented.Then,we elaborate on the tools and approaches undertaken for the design of porous scaffold with engineered internal architecture including,topology optimization techniques,as well as unit cell patterns based on lattice networks,and triply periodic minimal surface.Here,the new possibilities brought by the functionally gradient porous structures to meet the conflicting scaffold design requirements are thoroughly discussed.Subsequently,the design constraints and physical characteristics of the additively manufactured constructs are reviewed in terms of input parameters such as design features and AM processing parameters.We assess the proposed applications of additively manufactured implants for regeneration of different tissue types and the efforts made towards their clinical translation.Finally,we conclude the review with the emerging directions and perspectives for further development of AM in the medical industry.展开更多
基金A.S.would like to acknowledge the financial support from the Canadian Institutes of Health Research(CIHR)through a postdoctoral fellowship as well as the startup fund from The Pennsylvania State UniversityA.K.would like to acknowledge funding from the National Institutes of Health(1R01EB023052,1R01HL140618,CA257558,DK130566).We acknowledge UCLA CFAR grant 5P30 AI028697 and the UCLA AIDS Institute.The authors thank Profs.S.Li and M.Butte at UCLA for providing cryo-sectioning equipment and lab space for the blood coagulation tests,respectively.The authors also thank Prof.K.J.Lee for his advice on microneedle fabrication.
文摘Blood loss by hemorrhaging wounds accounts for over one-third of~5 million trauma fatalities worldwide every year.If not controlled in a timely manner,exsanguination can take lives within a few minutes.Developing new biomaterials that are easy to use by non-expert patients and promote rapid blood coagulation is an unmet medical need.Here,biocompatible,and biodegradable microneedle arrays(MNAs)based on gelatin methacryloyl(GelMA)biomaterial hybridized with silicate nanoplatelets(SNs)are developed for hemorrhage control.The SNs render the MNAs hemostatic,while the needle-shaped structure increases the contact area with blood,synergistically accelerating the clotting time from 11.5 min to 1.3 min in vitro.The engineered MNAs reduce bleeding by~92%compared with the untreated injury group in a rat liver bleeding model.SN-containing MNAs outperform the hemostatic effect of needle-free patches and a commercial hemostat in vivo via combining micro-and nanoengineered features.Furthermore,the tissue adhesive properties and mechanical interlocking support the suitability of MNAs for wound closure applications.These hemostatic MNAs may enable rapid hemorrhage control,particularly for patients in developing countries or remote areas with limited or no immediate access to hospitals.
基金funding from the National Institutes of Health(1R01AR073135-01A1)。
文摘Metal additive manufacturing(AM)has led to an evolution in the design and fabrication of hard tissue substitutes,enabling personalized implants to address each patient’s specific needs.In addition,internal pore architectures integrated within additively manufactured scaffolds,have provided an opportunity to further develop and engineer functional implants for better tissue integration,and long-term durability.In this review,the latest advances in different aspects of the design and manufacturing of additively manufactured metallic biomaterials are highlighted.After introducing metal AM processes,biocompatible metals adapted for integration with AM machines are presented.Then,we elaborate on the tools and approaches undertaken for the design of porous scaffold with engineered internal architecture including,topology optimization techniques,as well as unit cell patterns based on lattice networks,and triply periodic minimal surface.Here,the new possibilities brought by the functionally gradient porous structures to meet the conflicting scaffold design requirements are thoroughly discussed.Subsequently,the design constraints and physical characteristics of the additively manufactured constructs are reviewed in terms of input parameters such as design features and AM processing parameters.We assess the proposed applications of additively manufactured implants for regeneration of different tissue types and the efforts made towards their clinical translation.Finally,we conclude the review with the emerging directions and perspectives for further development of AM in the medical industry.
