The extracellular matrix,which includes collagens,laminin,or fibronectin,plays an important role in peripheral nerve regeneration.Recently,a Schwann cell-derived extracellular matrix with classical biomaterial was use...The extracellular matrix,which includes collagens,laminin,or fibronectin,plays an important role in peripheral nerve regeneration.Recently,a Schwann cell-derived extracellular matrix with classical biomaterial was used to mimic the neural niche.However,extensive clinical use of Schwann cells remains limited because of the limited origin,loss of an autologous nerve,and extended in vitro culture times.In the present study,human umbilical cord-derived mesenchymal stem cells(h UCMSCs),which are easily accessible and more proliferative than Schwann cells,were used to prepare an extracellular matrix.We identified the morphology and function of h UCMSCs and investigated their effect on peripheral nerve regeneration.Compared with a non-coated dish tissue culture,the h UCMSC-derived extracellular matrix enhanced Schwann cell proliferation,upregulated gene and protein expression levels of brain-derived neurotrophic factor,glial cell-derived neurotrophic factor,and vascular endothelial growth factor in Schwann cells,and enhanced neurite outgrowth from dorsal root ganglion neurons.These findings suggest that the h UCMSC-derived extracellular matrix promotes peripheral nerve repair and can be used as a basis for the rational design of engineered neural niches.展开更多
Veins are easy to obtain,have low immunogenicity,and induce a relatively weak inflammatory response.Therefore,veins have the potential to be used as conduits for nerve regeneration.However,because of the presence of v...Veins are easy to obtain,have low immunogenicity,and induce a relatively weak inflammatory response.Therefore,veins have the potential to be used as conduits for nerve regeneration.However,because of the presence of venous valves and the great elasticity of the venous wall,the vein is not conducive to nerve regeneration.In this study,a novel tissue engineered nerve graft was constructed by combining normal dissected nerve microtissue with an autologous vein graft for repairing 10-mm peripheral nerve defects in rats.Compared with rats given the vein graft alone,rats given the tissue engineered nerve graft had an improved sciatic static index,and a higher amplitude and shorter latency of compound muscle action potentials.Furthermore,rats implanted with the microtissue graft had a higher density and thickness of myelinated nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone.However,the tissue engineered nerve graft had a lower ability to repair the defect than autogenous nerve transplantation.In summary,although the tissue engineered nerve graft constructed with autologous vein and nerve microtissue is not as effective as autologous nerve transplantation for repairing long-segment sciatic nerve defects,it may nonetheless have therapeutic potential for the clinical repair of long sciatic nerve defects.This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital(approval No.2016-x9-07)on September 7,2016.展开更多
Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh...Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh cadaver knees were prepared by isolating the patella,leaving only the MPFL as its attachment to the medial condyle of femur.The MPFL was reconstructed by three different methods:four-suture fixation,anchors-single suture fixation,and anchors-double suture fixation.The tensile strength and the elongation of the normal MPFL and the tendon grafts were measured.Results The tensile strength of the four-suture fixation group(234.86±49.02 N)was stronger than that of the normal MPFL(146.91±25.30 N,P=0.0014)and the anchors-single suture group(159.17±49.07N,P=0.0077),while weaker than that of the anchors-double suture group(314.74±78.46 N,P=0.0052)Conclusions With regard to the tensile strength,the four-suture fixation method is reliable for clinical use.Compared with the anchor-suture method,the four-suture fixation method which has no specific implants is more economical,convenient and efficient.展开更多
In our previous study,we investigated the dynamic expression of cytokines in the distal nerve stumps after peripheral nerve injury using microarray analysis,which can characterize the dynamic expression of proteins.In...In our previous study,we investigated the dynamic expression of cytokines in the distal nerve stumps after peripheral nerve injury using microarray analysis,which can characterize the dynamic expression of proteins.In the present study,we used a rat model of right sciatic nerve transection to examine changes in the expression of cytokines at 1,7,14 and 28 days after injury using protein microarray analysis.Interleukins were increased in the distal nerve stumps at 1–14 days post nerve transection.However,growth factors and growth factor-related proteins were mainly upregulated in the proximal nerve stumps.The P-values of the inflammatory response,apoptotic response and cell-cell adhesion in the distal stumps were higher than those in the proximal nerve stumps,but the opposite was observed for angiogenesis.The number of cytokines related to axons in the distal stumps was greater than that in the proximal stumps,while the percentage of cytokines related to axons in the distal stumps was lower than that in the proximal nerve stumps.Visualization of the results revealed the specific expression patterns and differences in cytokines in and between the proximal and distal nerve stumps.Our findings offer potential therapeutic targets and should help advance the development of clinical treatments for peripheral nerve injury.Approval for animal use in this study was obtained from the Animal Ethics Committee of the Chinese PLA General Hospital on September 7,2016(approval No.2016-x9-07).展开更多
基金supported by the National Natural Science Foundation of China,Grant No.31170946the National Program on Key Basic Research Project of China(973 Program)+1 种基金Grant No.2012CB518106 and No.2014CB542201the Special Project of the“Twelfth Five-year Plan”for Medical Science Development of PLA,No.BWS13C029
文摘The extracellular matrix,which includes collagens,laminin,or fibronectin,plays an important role in peripheral nerve regeneration.Recently,a Schwann cell-derived extracellular matrix with classical biomaterial was used to mimic the neural niche.However,extensive clinical use of Schwann cells remains limited because of the limited origin,loss of an autologous nerve,and extended in vitro culture times.In the present study,human umbilical cord-derived mesenchymal stem cells(h UCMSCs),which are easily accessible and more proliferative than Schwann cells,were used to prepare an extracellular matrix.We identified the morphology and function of h UCMSCs and investigated their effect on peripheral nerve regeneration.Compared with a non-coated dish tissue culture,the h UCMSC-derived extracellular matrix enhanced Schwann cell proliferation,upregulated gene and protein expression levels of brain-derived neurotrophic factor,glial cell-derived neurotrophic factor,and vascular endothelial growth factor in Schwann cells,and enhanced neurite outgrowth from dorsal root ganglion neurons.These findings suggest that the h UCMSC-derived extracellular matrix promotes peripheral nerve repair and can be used as a basis for the rational design of engineered neural niches.
基金This work was supported by the National Natural Science Foundation of China,Nos.31771052(to YW),81671684(to YXW),81871788(to CZ)National Key Research and Development Program of China,Nos.2017YFA0104702,2017YFA0104703+3 种基金the Natural Science Foundation of Beijing of China,No.7172202(to YW)PLA Youth Training Project for Medical Science of China,No.16QNP144(to YW),the Project for Science and Technology Leader of Anhui Province of China,No.2018H177(to CZ)Funding of“Panfeng”Innovation Team Project for Scientifc Research of Yijishan Hospital,Wannan Medical College,China,No.PF2019007(to HGX)Funding of“Peak”Training Program for Scientifc Research of Yijishan Hospital,Wannan Medical College,China,No.GF2019T02(to HGX).
文摘Veins are easy to obtain,have low immunogenicity,and induce a relatively weak inflammatory response.Therefore,veins have the potential to be used as conduits for nerve regeneration.However,because of the presence of venous valves and the great elasticity of the venous wall,the vein is not conducive to nerve regeneration.In this study,a novel tissue engineered nerve graft was constructed by combining normal dissected nerve microtissue with an autologous vein graft for repairing 10-mm peripheral nerve defects in rats.Compared with rats given the vein graft alone,rats given the tissue engineered nerve graft had an improved sciatic static index,and a higher amplitude and shorter latency of compound muscle action potentials.Furthermore,rats implanted with the microtissue graft had a higher density and thickness of myelinated nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone.However,the tissue engineered nerve graft had a lower ability to repair the defect than autogenous nerve transplantation.In summary,although the tissue engineered nerve graft constructed with autologous vein and nerve microtissue is not as effective as autologous nerve transplantation for repairing long-segment sciatic nerve defects,it may nonetheless have therapeutic potential for the clinical repair of long sciatic nerve defects.This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital(approval No.2016-x9-07)on September 7,2016.
文摘Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh cadaver knees were prepared by isolating the patella,leaving only the MPFL as its attachment to the medial condyle of femur.The MPFL was reconstructed by three different methods:four-suture fixation,anchors-single suture fixation,and anchors-double suture fixation.The tensile strength and the elongation of the normal MPFL and the tendon grafts were measured.Results The tensile strength of the four-suture fixation group(234.86±49.02 N)was stronger than that of the normal MPFL(146.91±25.30 N,P=0.0014)and the anchors-single suture group(159.17±49.07N,P=0.0077),while weaker than that of the anchors-double suture group(314.74±78.46 N,P=0.0052)Conclusions With regard to the tensile strength,the four-suture fixation method is reliable for clinical use.Compared with the anchor-suture method,the four-suture fixation method which has no specific implants is more economical,convenient and efficient.
基金This study was supported by the National Natural Science Foundation of China,No.31771052(to YW)the National Key R&D Program of China,No.2017YFA0104702(to AJS)the Youth Cultivation Project of Military Medical Science,No.16QNP144(to YW).
文摘In our previous study,we investigated the dynamic expression of cytokines in the distal nerve stumps after peripheral nerve injury using microarray analysis,which can characterize the dynamic expression of proteins.In the present study,we used a rat model of right sciatic nerve transection to examine changes in the expression of cytokines at 1,7,14 and 28 days after injury using protein microarray analysis.Interleukins were increased in the distal nerve stumps at 1–14 days post nerve transection.However,growth factors and growth factor-related proteins were mainly upregulated in the proximal nerve stumps.The P-values of the inflammatory response,apoptotic response and cell-cell adhesion in the distal stumps were higher than those in the proximal nerve stumps,but the opposite was observed for angiogenesis.The number of cytokines related to axons in the distal stumps was greater than that in the proximal stumps,while the percentage of cytokines related to axons in the distal stumps was lower than that in the proximal nerve stumps.Visualization of the results revealed the specific expression patterns and differences in cytokines in and between the proximal and distal nerve stumps.Our findings offer potential therapeutic targets and should help advance the development of clinical treatments for peripheral nerve injury.Approval for animal use in this study was obtained from the Animal Ethics Committee of the Chinese PLA General Hospital on September 7,2016(approval No.2016-x9-07).
