Recent years, it has attracted more attentions to increase the porosity and pore size of nanofibrous scaffolds to provide the for the cells to grow into the small-diameter vascular grafts. In this study, a novel bi-la...Recent years, it has attracted more attentions to increase the porosity and pore size of nanofibrous scaffolds to provide the for the cells to grow into the small-diameter vascular grafts. In this study, a novel bi-layer tubular scaffold with an inner layer and an outer layer was fabricated. The inner layer was random collagen/poly （ L-lactide-co-caprolactone ） I P （ LLA- CL） ] nanofibrous mat fabricated by conventional electrospinning and the outer layer was aligned collagen/P （LLA-CL） nanoyarns prepared by a dynamic liquid dectrospinning method. Fourier transform infrared spectroscopy （FTIR） was used to characterize the chemical structure. Scanning electron microscopy （ SEM ） was employed to observe the morphology of the layers and the cross- sectioned bi-layer tubular scaffold. A liquid displacement method was employed to measure the porosities of the inner and outer layers. Stress-strain curves were obtained to evaluate the mechanical properties of the two different layers and the bi-layer membrane. The diameters of the nanofibers and the nanoyarns were （480 ± 197 ） nm and （ 19.66 ± 4.05 ） μm, respectively. The outer layer had a significantly higher porosity and a larger pore size than those of the inner layer. Furthermore, the bi-layer membrane showed a good mechanical property which was suitable as small-diameter vascular graft. The results indicated that the bi-layer tubular scaffold had a great potential application in small vascular tissue engineering.展开更多
Urethral strictures were common disease caused by over-expression of extracellular matrix from fibroblast. In this study, we compare two nanoyarn scaffolds for improving fibroblasts infiltration without inhibition the...Urethral strictures were common disease caused by over-expression of extracellular matrix from fibroblast. In this study, we compare two nanoyarn scaffolds for improving fibroblasts infiltration without inhibition the over-expression of extracellular matrix. Collagenlpoly（L-lactide-co-caprolactone）（ColIP（LLA-CL）） nanoyarn scaffolds were prepared by conjugated electrospinning and dynamic liquid electrospinning, respectively, in addition, co-axial electrospinning technique was combined with the nanoyarn fabrication process to produce nanoyarn scaffolds loading Wntsignaling pathway inhibitor. The mechanical properties of the scaffolds were examined and morphology was observed by SEM. Cell morphology, proliferation and infiltration on the scaffolds were investigated by SEM, MTT assay and H＆E staining, respectively. The release profiles of different scaffolds were determined using HPLC. The results indicated that cells showed an organized morphology along the nanoyarns and considerable infiltration into the nanoyarn scaffolds prepared by dynamic liquid electrospinning （DLY）. It was also observed that the DLY significantly facilitate cell proliferation. The D-DLY could facilitate the infiltration of the fibroblasts and could be a promising scaffold for the treatment of urethra stricture while it may inhibit the collagen production.展开更多
Insufficient bionic performance is a structural obstacle and makes urethral repair unobtainable.To overcome this challenge,we mimicked the urethral matrix and applied two electrospinning techniques to build a double-l...Insufficient bionic performance is a structural obstacle and makes urethral repair unobtainable.To overcome this challenge,we mimicked the urethral matrix and applied two electrospinning techniques to build a double-layer sponge tube of nanofib-ers and nanoyarns.Intriguingly,silk fibroin(SF)and vitamin B5(VitB5)could be introduced to increase the elasticity of the outer layer and reduce the hydrophobicity to further improve mesenchymal cell proliferation.Systematic experiments validated the bionic structure,biocompatibility,and exosome delivery capacity in this scaffold.We achieved scarless urethral repair by delivering the bioactive growth factors from adipose-derived stem cell exosomes by physical absorption.Biological regeneration of the urethra can be accomplished with continuous epithelium in animals.Furthermore,bioinformatics studies revealed that the expression of cell proliferation and fibrotic genes(e.g.,Wnt7a,cfa-miR-574)was responsible for the bio-logical regeneration of the adipose-derived stem cells exosomes(ADSC-exos)by delivering poly l-lactide-co-caprolactone/SF/VitB5 bilayer sponge(PSVBS)via reduced fibrosis gene expression,as well as improved epithelial formation and blood vessel formation.Therefore,the PSVBS design appeared to be an instructive approach for urethral and other tubular organ regeneration.展开更多
基金National Natural Science Foundations of China，Science and Technology Commission of Shanghai Municipality,China，Ph.D.Programs Foundation of Ministry of Education of China
文摘Recent years, it has attracted more attentions to increase the porosity and pore size of nanofibrous scaffolds to provide the for the cells to grow into the small-diameter vascular grafts. In this study, a novel bi-layer tubular scaffold with an inner layer and an outer layer was fabricated. The inner layer was random collagen/poly （ L-lactide-co-caprolactone ） I P （ LLA- CL） ] nanofibrous mat fabricated by conventional electrospinning and the outer layer was aligned collagen/P （LLA-CL） nanoyarns prepared by a dynamic liquid dectrospinning method. Fourier transform infrared spectroscopy （FTIR） was used to characterize the chemical structure. Scanning electron microscopy （ SEM ） was employed to observe the morphology of the layers and the cross- sectioned bi-layer tubular scaffold. A liquid displacement method was employed to measure the porosities of the inner and outer layers. Stress-strain curves were obtained to evaluate the mechanical properties of the two different layers and the bi-layer membrane. The diameters of the nanofibers and the nanoyarns were （480 ± 197 ） nm and （ 19.66 ± 4.05 ） μm, respectively. The outer layer had a significantly higher porosity and a larger pore size than those of the inner layer. Furthermore, the bi-layer membrane showed a good mechanical property which was suitable as small-diameter vascular graft. The results indicated that the bi-layer tubular scaffold had a great potential application in small vascular tissue engineering.
文摘Urethral strictures were common disease caused by over-expression of extracellular matrix from fibroblast. In this study, we compare two nanoyarn scaffolds for improving fibroblasts infiltration without inhibition the over-expression of extracellular matrix. Collagenlpoly（L-lactide-co-caprolactone）（ColIP（LLA-CL）） nanoyarn scaffolds were prepared by conjugated electrospinning and dynamic liquid electrospinning, respectively, in addition, co-axial electrospinning technique was combined with the nanoyarn fabrication process to produce nanoyarn scaffolds loading Wntsignaling pathway inhibitor. The mechanical properties of the scaffolds were examined and morphology was observed by SEM. Cell morphology, proliferation and infiltration on the scaffolds were investigated by SEM, MTT assay and H＆E staining, respectively. The release profiles of different scaffolds were determined using HPLC. The results indicated that cells showed an organized morphology along the nanoyarns and considerable infiltration into the nanoyarn scaffolds prepared by dynamic liquid electrospinning （DLY）. It was also observed that the DLY significantly facilitate cell proliferation. The D-DLY could facilitate the infiltration of the fibroblasts and could be a promising scaffold for the treatment of urethra stricture while it may inhibit the collagen production.
基金National Natural Science Fund of China(Grant no.82170694,81700590)the Shanghai Jiao Tong University Biomedical Engineering Cross Research Foundation(Grant no.YG2022ZD020,YG2017QN15)+4 种基金Shanghai health committee(XHLHGG20,20184Y0053)Shanghai natural science foundation(20ZR144210)iangsu Key R&D Plan(BE2017664)Shanghai"Rising stars of medical talent"Youth development program,Shanghai Jiao Tong University K.C.Wong Medical Fellowship Fund.The Talent Program of Shanghai University of Engineering Science(QNTD202104)Shanghai Local Universities Capacity Building Project of Science and Technology Innovation Action Program(21010501700).
文摘Insufficient bionic performance is a structural obstacle and makes urethral repair unobtainable.To overcome this challenge,we mimicked the urethral matrix and applied two electrospinning techniques to build a double-layer sponge tube of nanofib-ers and nanoyarns.Intriguingly,silk fibroin(SF)and vitamin B5(VitB5)could be introduced to increase the elasticity of the outer layer and reduce the hydrophobicity to further improve mesenchymal cell proliferation.Systematic experiments validated the bionic structure,biocompatibility,and exosome delivery capacity in this scaffold.We achieved scarless urethral repair by delivering the bioactive growth factors from adipose-derived stem cell exosomes by physical absorption.Biological regeneration of the urethra can be accomplished with continuous epithelium in animals.Furthermore,bioinformatics studies revealed that the expression of cell proliferation and fibrotic genes(e.g.,Wnt7a,cfa-miR-574)was responsible for the bio-logical regeneration of the adipose-derived stem cells exosomes(ADSC-exos)by delivering poly l-lactide-co-caprolactone/SF/VitB5 bilayer sponge(PSVBS)via reduced fibrosis gene expression,as well as improved epithelial formation and blood vessel formation.Therefore,the PSVBS design appeared to be an instructive approach for urethral and other tubular organ regeneration.
