Since 3D printed hard materials could match the shape of bone,cell survival and fate determination towards osteoblasts in such materials have become a popular research target.In this study,a scaffold of hardmaterial f...Since 3D printed hard materials could match the shape of bone,cell survival and fate determination towards osteoblasts in such materials have become a popular research target.In this study,a scaffold of hardmaterial for 3D fabrication was designed to regulate developmental signal(Notch)transduction guiding osteoblast differentiation.We established a polycaprolactone(PCL)and cell-integrated 3D printing system(PCI3D)to reciprocally print the beams of PCL and cell-laden hydrogel for a module.This PCI3D module holds good cell viability of over 87%,whereas cells show about sixfold proliferation in a 7-day culture.The osteocytic MLO-Y4 was engineered to overexpress Notch ligand Dll4,making up 25%after mixing with 75%stromal cells in the PCI3D module.Osteocytic Dll4,unlike other delta-like family members such as Dll1 or Dll3,promotes osteoblast differentiation and themineralization of primary mouse and a cell line of bone marrow stromal cells when cultured in a PCI3D module for up to 28 days.Mechanistically,osteocytic Dll4 could not promote osteogenic differentiation of the primary bone marrow stromal cells(BMSCs)after conditional deletion of the Notch transcription factor RBPjκby Cre recombinase.These data indicate that osteocytic Dll4 activates RBPjκ-dependent canonical Notch signaling in BMSCs for their oriented differentiation towards osteoblasts.Additionally,osteocytic Dll4 holds a great potential for angiogenesis in human umbilical vein endothelial cells within modules.Our study reveals that osteocytic Dll4 could be the osteogenic niche determining cell fate towards osteoblasts.This will open a new avenue to overcome the current limitation of poor cell viability and low bioactivity of traditional orthopedic implants.展开更多
The thermal behavior, miscibility, crystallite conformation and thermal stability ofcrosslinked(CL-) PVA/PVP blends were studied by DSC and TG methods, respectively. DSCresults showed that in the blend, the crystallin...The thermal behavior, miscibility, crystallite conformation and thermal stability ofcrosslinked(CL-) PVA/PVP blends were studied by DSC and TG methods, respectively. DSCresults showed that in the blend, the crystallinity,T_m and T_c of PVA were obviously lower thanthose of pure PVA; the crystal growth changed from three dimensional to two dimensional andonly a single T_g was detected. These facts demonstrated that this crystalline and amorphousblend have good miscibility. TG curves showed that providing the quantity of K_2S_2O_8 added ismore than 3 wt%,in the blends PVA will form a stable CL-network, whose thermal degradationtemperature was near to that of PVP. But crosslinking reaction will not take place for PVP. Theprocesses of thermal degradation of CL-blends are based on combining both the thermaldegradation of PVP and that of PVA crosslinked with corresponding quantity of K_2S_2O_8 CL-agent, respectively. The UV measurements showed that 75 wt% of PVP may be remained in CL-blend hydrogelscrosslinked by adding (3--5 wt% )K_2S_2O_8. This is mainly due to the stable CL-network formed and the good compatibility and properentanglement between the composites in the CL-blends.展开更多
The application of antifouling paints to the surfaces of marine installations is the most economically efficient means for mitigating damage caused by marine biofouling in the shipping industry.However,conventional an...The application of antifouling paints to the surfaces of marine installations is the most economically efficient means for mitigating damage caused by marine biofouling in the shipping industry.However,conventional antifouling paints currently in widespread use can no longer meet the requirements of green antifouling.Although hydrogel coatings have made great progress in marine antifouling applications,current hydrogel coatings still suffer from construction difficulties and poor mechanical stability under wet conditions.In this paper,we innovatively exploit the phenomenon of the absorption of pyrogallol(PG)by large-molecular-weight polyvinylpyrrolidone(PVP),resulting in hydro-philic copolymer macromolecules,to propose a prepolymer-reactor rapid contact molding of sprayable hydrogel coatings.The PG/PVP copolymer produced microscopic reticular mimetic mussel adhesion protein(MAP)bioscaffolds via the chemical crosslinking of polyethyleneimine(PEI),contributed to the conversion of PG to PG-quinone upon the introduction of vanadium pentoxide particles,increased the hydrophobicity of the system and enhanced waterproof adhesion.The wet adhesion of the hydrogel coatings was measured up to 3.42 MPa via the micrometer scratch method,indicating that the prepared hydrogel coating had a stable adhesive force in a wet environment.The hydrogel coating was instantly molded on the surface of 304 stainless steel(SS)via two-step spraying.The swelling,friction,antifouling,and anticorrosion properties of the coatings were investigated along with the wet adhesion strength on the SS surfaces.The results showed that the hydrogel,after double cross-linking of PEI and V2O5,had a swelling rate within 30%and a low modulus along with stable lubricating properties.After the formation of the hydrogel coating,the inhibition rate of common bacteria and algae in the ocean reached more than 99%,and the electrochemical corrosion protection rate of SS reached 63.49%.This study provided ideas for improving the wet adhesion of hydrophilic marine antifouling coatings.展开更多
In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of...In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of PVP interaction, mechanical property and transparence of PVA/PVP hydrogel was investigated and evaluated by FT-IR analysis, mechanical test machine and UV spectrophotometer. The results showed that when the content of PVP was 8% in the DMSO aqueous solution, the highest transparence of PVA/PVP hydrogel was obtained, with excellent tensile strength values higher than 3.5 MPa. Therefore, the PVA/PVP hydrogel composite has a potential to be used as the transparent core of a novel artificial cornea.展开更多
基金the National Natural Science Foundation of China(Nos.U1601220,82072450,and 81672118)Chongqing Science and Technology Commission-Basic Science and Frontier Technology Key Project(No.cstc2015jcyjBX0119)Chongqing Medical University Intelligent Medicine Research Project(No.ZHYX202115).
文摘Since 3D printed hard materials could match the shape of bone,cell survival and fate determination towards osteoblasts in such materials have become a popular research target.In this study,a scaffold of hardmaterial for 3D fabrication was designed to regulate developmental signal(Notch)transduction guiding osteoblast differentiation.We established a polycaprolactone(PCL)and cell-integrated 3D printing system(PCI3D)to reciprocally print the beams of PCL and cell-laden hydrogel for a module.This PCI3D module holds good cell viability of over 87%,whereas cells show about sixfold proliferation in a 7-day culture.The osteocytic MLO-Y4 was engineered to overexpress Notch ligand Dll4,making up 25%after mixing with 75%stromal cells in the PCI3D module.Osteocytic Dll4,unlike other delta-like family members such as Dll1 or Dll3,promotes osteoblast differentiation and themineralization of primary mouse and a cell line of bone marrow stromal cells when cultured in a PCI3D module for up to 28 days.Mechanistically,osteocytic Dll4 could not promote osteogenic differentiation of the primary bone marrow stromal cells(BMSCs)after conditional deletion of the Notch transcription factor RBPjκby Cre recombinase.These data indicate that osteocytic Dll4 activates RBPjκ-dependent canonical Notch signaling in BMSCs for their oriented differentiation towards osteoblasts.Additionally,osteocytic Dll4 holds a great potential for angiogenesis in human umbilical vein endothelial cells within modules.Our study reveals that osteocytic Dll4 could be the osteogenic niche determining cell fate towards osteoblasts.This will open a new avenue to overcome the current limitation of poor cell viability and low bioactivity of traditional orthopedic implants.
文摘The thermal behavior, miscibility, crystallite conformation and thermal stability ofcrosslinked(CL-) PVA/PVP blends were studied by DSC and TG methods, respectively. DSCresults showed that in the blend, the crystallinity,T_m and T_c of PVA were obviously lower thanthose of pure PVA; the crystal growth changed from three dimensional to two dimensional andonly a single T_g was detected. These facts demonstrated that this crystalline and amorphousblend have good miscibility. TG curves showed that providing the quantity of K_2S_2O_8 added ismore than 3 wt%,in the blends PVA will form a stable CL-network, whose thermal degradationtemperature was near to that of PVP. But crosslinking reaction will not take place for PVP. Theprocesses of thermal degradation of CL-blends are based on combining both the thermaldegradation of PVP and that of PVA crosslinked with corresponding quantity of K_2S_2O_8 CL-agent, respectively. The UV measurements showed that 75 wt% of PVP may be remained in CL-blend hydrogelscrosslinked by adding (3--5 wt% )K_2S_2O_8. This is mainly due to the stable CL-network formed and the good compatibility and properentanglement between the composites in the CL-blends.
基金supported by the National Natural Science Foundation of China(Nos.52275209 and 51905468)the Jiangsu Province Graduate Student Practice and Innovation Program(No.SJCX23_1912).
文摘The application of antifouling paints to the surfaces of marine installations is the most economically efficient means for mitigating damage caused by marine biofouling in the shipping industry.However,conventional antifouling paints currently in widespread use can no longer meet the requirements of green antifouling.Although hydrogel coatings have made great progress in marine antifouling applications,current hydrogel coatings still suffer from construction difficulties and poor mechanical stability under wet conditions.In this paper,we innovatively exploit the phenomenon of the absorption of pyrogallol(PG)by large-molecular-weight polyvinylpyrrolidone(PVP),resulting in hydro-philic copolymer macromolecules,to propose a prepolymer-reactor rapid contact molding of sprayable hydrogel coatings.The PG/PVP copolymer produced microscopic reticular mimetic mussel adhesion protein(MAP)bioscaffolds via the chemical crosslinking of polyethyleneimine(PEI),contributed to the conversion of PG to PG-quinone upon the introduction of vanadium pentoxide particles,increased the hydrophobicity of the system and enhanced waterproof adhesion.The wet adhesion of the hydrogel coatings was measured up to 3.42 MPa via the micrometer scratch method,indicating that the prepared hydrogel coating had a stable adhesive force in a wet environment.The hydrogel coating was instantly molded on the surface of 304 stainless steel(SS)via two-step spraying.The swelling,friction,antifouling,and anticorrosion properties of the coatings were investigated along with the wet adhesion strength on the SS surfaces.The results showed that the hydrogel,after double cross-linking of PEI and V2O5,had a swelling rate within 30%and a low modulus along with stable lubricating properties.After the formation of the hydrogel coating,the inhibition rate of common bacteria and algae in the ocean reached more than 99%,and the electrochemical corrosion protection rate of SS reached 63.49%.This study provided ideas for improving the wet adhesion of hydrophilic marine antifouling coatings.
基金National Natural Science Foundation of Chinagrant number:11002016,30900306,81171473 and 11032012
文摘In this paper, transparent poly(vinyl alcohol)/poly(vinyl pyrrolidone)(PVA/PVP) hydrogels were prepared by using the solvent of dimethyl sulfoxide(DMSO) aqueous solution and the method of freeze/thawing. The effect of PVP interaction, mechanical property and transparence of PVA/PVP hydrogel was investigated and evaluated by FT-IR analysis, mechanical test machine and UV spectrophotometer. The results showed that when the content of PVP was 8% in the DMSO aqueous solution, the highest transparence of PVA/PVP hydrogel was obtained, with excellent tensile strength values higher than 3.5 MPa. Therefore, the PVA/PVP hydrogel composite has a potential to be used as the transparent core of a novel artificial cornea.
