The use of various types of calcium phosphate has been reported in the preparation of repairing materials for bone defects.However,the physicochemical and biological properties among them might be vastly different.In ...The use of various types of calcium phosphate has been reported in the preparation of repairing materials for bone defects.However,the physicochemical and biological properties among them might be vastly different.In this study,we prepared two types of calcium phosphates,nano-hydroxyapatite(nHA)and natural bone ceramic(NBC),into 3D scaffolds by mixing with type I collagen(CoL),resulting in the nHA/CoL and NBC/CoL scaffolds.We then evaluated and compared the physicochemical and biological properties of these two calcium phosphates and their composite scaffold with CoL.Scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),X-ray diffraction spectroscopy(XRD)and compressive tests were used to,respectively,characterize the morphology,composition,distribution and the effect of nHA and NBC to collagen.Next,we examined the biological properties of the scaffolds using cytotoxicity testing,flow cytometry,immunofluorescence staining,biocompatibility testing,CCK-8 assays and RT-PCR.The results reflected that the Ca2t released from nHA and NBC could bind chemically with collagen and affect its physicochemical properties,including the infrared absorption spectrum and compression modulus,among others.Furthermore,the two kinds of scaffolds could promote the expression of osteo-relative genes,but showed different gene induction properties.In short,NBC/CoL could promote the expression of early osteogenic genes,while nHA/CoL could upregulate late osteogenic genes.Conclusively,these two composite scaffolds could provide MC3T3-E1 cells with a biomimetic surface for adhesion,proliferation and the formation of mineralized extracellular matrices.Moreover,nHA/CoL and NBC/CoL had different effects on the period and extent ofMC3T3-E1 cell mineralization.展开更多
To study the effect of two composition ratios of nano-hydroxyapatite and collagen(NHAC)composites on repairing alveolar bone defect of dogs.Eighteen healthy adult dogs were randomly divided into three groups.Two kinds...To study the effect of two composition ratios of nano-hydroxyapatite and collagen(NHAC)composites on repairing alveolar bone defect of dogs.Eighteen healthy adult dogs were randomly divided into three groups.Two kinds of the NHAC composites were prepared according to the constituent ratios of 3:7 and 5:5;immediately after extraction of the mandibular second premolars,each kind of the NHAC composite was implanted into extraction socket,respectively:Group I,nHA/Col紏3:7;Group II,nHA/Col紏5:5 and Group III,blank control group.The bone-repairing ability of the two grafts was separately analyzed by morphometric measurement,X-ray tomography examination and biomechanical analysis at 1st,3rd and 6th month post-surgical,respectively.The NHAC composites were absorbed gradually after implanting into alveolar bone defect and were replaced by new bone.The ratios of new bone formation of Group I was significantly higher than that of Group II after 3 months(P<0.05).The structure and bioactive performance can be improved when the ratio between the collagen and the hydroxyapatite was reasonable,and the repairing ability and effect in extraction sockets are obviously better.展开更多
Chitin is a kind of seemly material to match PLLA for a scaffold, which may create an appropriate environment for the regeneration of tissues. In this study, we evaluated hydrophilicity of a new nano-hydroxyapatite/co...Chitin is a kind of seemly material to match PLLA for a scaffold, which may create an appropriate environment for the regeneration of tissues. In this study, we evaluated hydrophilicity of a new nano-hydroxyapatite/collagen/PLLA (nHACP) scaffold optimized by chitin fibres for bone tissue engineering. The results show that with the CF content increase, hydrophilicity of nHACP/CF increases, which reflects from the side that the addition of the chitin fibres can improve the cytocompatibility of the nHACP. Moreover, crosslink does not take significant influences on the material hydrophilicity. The results suggest that nHACP/CF with the crosslink should be a kind of potential appropriate scaffold for tissue engineering.展开更多
基金the National Key Research and Development Program of China(2018YFA0108200,2018YFC116400)the International Cooperation Project of Hainan Province(KJHZ2015-30)Sci&Tech Program of Guangzhou of China(201803010086).
文摘The use of various types of calcium phosphate has been reported in the preparation of repairing materials for bone defects.However,the physicochemical and biological properties among them might be vastly different.In this study,we prepared two types of calcium phosphates,nano-hydroxyapatite(nHA)and natural bone ceramic(NBC),into 3D scaffolds by mixing with type I collagen(CoL),resulting in the nHA/CoL and NBC/CoL scaffolds.We then evaluated and compared the physicochemical and biological properties of these two calcium phosphates and their composite scaffold with CoL.Scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Fourier-transform infrared spectroscopy(FTIR),X-ray diffraction spectroscopy(XRD)and compressive tests were used to,respectively,characterize the morphology,composition,distribution and the effect of nHA and NBC to collagen.Next,we examined the biological properties of the scaffolds using cytotoxicity testing,flow cytometry,immunofluorescence staining,biocompatibility testing,CCK-8 assays and RT-PCR.The results reflected that the Ca2t released from nHA and NBC could bind chemically with collagen and affect its physicochemical properties,including the infrared absorption spectrum and compression modulus,among others.Furthermore,the two kinds of scaffolds could promote the expression of osteo-relative genes,but showed different gene induction properties.In short,NBC/CoL could promote the expression of early osteogenic genes,while nHA/CoL could upregulate late osteogenic genes.Conclusively,these two composite scaffolds could provide MC3T3-E1 cells with a biomimetic surface for adhesion,proliferation and the formation of mineralized extracellular matrices.Moreover,nHA/CoL and NBC/CoL had different effects on the period and extent ofMC3T3-E1 cell mineralization.
基金supported by the National Natural Science Foundation of China(grant no.21371106)and the Science&Technology Project of Liaoning Province(grant no.2015020689).
文摘To study the effect of two composition ratios of nano-hydroxyapatite and collagen(NHAC)composites on repairing alveolar bone defect of dogs.Eighteen healthy adult dogs were randomly divided into three groups.Two kinds of the NHAC composites were prepared according to the constituent ratios of 3:7 and 5:5;immediately after extraction of the mandibular second premolars,each kind of the NHAC composite was implanted into extraction socket,respectively:Group I,nHA/Col紏3:7;Group II,nHA/Col紏5:5 and Group III,blank control group.The bone-repairing ability of the two grafts was separately analyzed by morphometric measurement,X-ray tomography examination and biomechanical analysis at 1st,3rd and 6th month post-surgical,respectively.The NHAC composites were absorbed gradually after implanting into alveolar bone defect and were replaced by new bone.The ratios of new bone formation of Group I was significantly higher than that of Group II after 3 months(P<0.05).The structure and bioactive performance can be improved when the ratio between the collagen and the hydroxyapatite was reasonable,and the repairing ability and effect in extraction sockets are obviously better.
基金National Natural Science Foundation of Chinagrant number:31000431 and 10925208+1 种基金Bejing Nove Programgrant number:2010B011
文摘Chitin is a kind of seemly material to match PLLA for a scaffold, which may create an appropriate environment for the regeneration of tissues. In this study, we evaluated hydrophilicity of a new nano-hydroxyapatite/collagen/PLLA (nHACP) scaffold optimized by chitin fibres for bone tissue engineering. The results show that with the CF content increase, hydrophilicity of nHACP/CF increases, which reflects from the side that the addition of the chitin fibres can improve the cytocompatibility of the nHACP. Moreover, crosslink does not take significant influences on the material hydrophilicity. The results suggest that nHACP/CF with the crosslink should be a kind of potential appropriate scaffold for tissue engineering.