Damage of axon and glial scars formation both inhibit nerve regenerative growth during nerve injury.In addition,mechanical stretch at high displacement rates of 10%tensile strain can cause marked nerve injury,it is im...Damage of axon and glial scars formation both inhibit nerve regenerative growth during nerve injury.In addition,mechanical stretch at high displacement rates of 10%tensile strain can cause marked nerve injury,it is important for finding a proper nano biomaterial to repair nerve injury.Nano-hydroxyapatite(n-HA)has excellent biocompatibility and high bioactivity,which is a good candidate for biomedical engineering applications.But the certain mechanism of n-HA on the injured nerve is seldom reported.In this study,we determined the role of n-HA on the mechanical stretch-induced nerve injury at adult rat spine.Mechanical stretch under strain 10%at displacement rates of 60 mm/min can cause marked broken vessels and edema in spinal cord and dorsal root ganglion tissue in haematoxylin-eosin(HE)staining.However,n-HA application can reverse hemorrhage and edema triggered by high rates of 60 mm/min stretch.Moreover,n-HA can promote positive staining of Netrin-1 increase significantly in spinal cord and dorsal root ganglion tested by immunohistochemistry(IHC)staining.In general,our study indicated that n-HA can repair mechanical stretch-induced nerve injury,it may provide a new approach to block injury and accelerate nerve regeneration in future.展开更多
Nano-hydroxyapatite/poly（e-caprolactone） （nHA/PCL） composite materials are among the best candidates for application in bone tissue engineering. As the main technique to fabricate porous scaffolds, electrospilming...Nano-hydroxyapatite/poly（e-caprolactone） （nHA/PCL） composite materials are among the best candidates for application in bone tissue engineering. As the main technique to fabricate porous scaffolds, electrospilming produce scaffolds with unsatisfactory mechanical strength and limited pore size for cdi infiltration. Micron-sized fiber assembly with higher mechanical strength is qualified to structure hybrid scaffolds. In this study, nHA/PCL monofilament fibers with different mass ratios were fabricated through melt-spinning. Transmission electron microscope （TEM） was used to observe the aggregation between nHA parfides. Other characterizations including scanning electron microscopy （SEM）, attenuated total reflection Fourier transform infrared spectroscopy （ATR.FTIR） and X-ray diffraction （XRD） were done to discuss the morphology, components and crystallization of the nHA/PCL composite fibers, respectively. The influence of nHA/PCL mass ratio on the tensile properties and water contact angle of composite fibers was also studied. The SEM images show the homogeneous dispersion of nano partides in the polymer matrix. Besides, nHA content increases the tensile strength, initial modulus and hydrophillcity of the composite fibers under the premise of spinnability. This kind of fibers is strong enough to fabricate fiber assembly which may have potential application in bone tissue engineering.展开更多
基金supported by funds from the National Natural Science Foundation of China(NSFC)Research Grant(31971238,51574246,61871014,11827803,31771019)National Key Research and Development Program(2016YFC1100704,2016YFC1102203)+1 种基金also supported by 111 Project(B13003)International Joint Research Center of Aerospace Biotechnology and Medical Engineering,Ministry of Science and Technology,China.
文摘Damage of axon and glial scars formation both inhibit nerve regenerative growth during nerve injury.In addition,mechanical stretch at high displacement rates of 10%tensile strain can cause marked nerve injury,it is important for finding a proper nano biomaterial to repair nerve injury.Nano-hydroxyapatite(n-HA)has excellent biocompatibility and high bioactivity,which is a good candidate for biomedical engineering applications.But the certain mechanism of n-HA on the injured nerve is seldom reported.In this study,we determined the role of n-HA on the mechanical stretch-induced nerve injury at adult rat spine.Mechanical stretch under strain 10%at displacement rates of 60 mm/min can cause marked broken vessels and edema in spinal cord and dorsal root ganglion tissue in haematoxylin-eosin(HE)staining.However,n-HA application can reverse hemorrhage and edema triggered by high rates of 60 mm/min stretch.Moreover,n-HA can promote positive staining of Netrin-1 increase significantly in spinal cord and dorsal root ganglion tested by immunohistochemistry(IHC)staining.In general,our study indicated that n-HA can repair mechanical stretch-induced nerve injury,it may provide a new approach to block injury and accelerate nerve regeneration in future.
基金Science and Technology Support Program of Shanghai,China(No.16441903803)National Postdoctoral Foundation,China(No.2016M590299)
文摘Nano-hydroxyapatite/poly（e-caprolactone） （nHA/PCL） composite materials are among the best candidates for application in bone tissue engineering. As the main technique to fabricate porous scaffolds, electrospilming produce scaffolds with unsatisfactory mechanical strength and limited pore size for cdi infiltration. Micron-sized fiber assembly with higher mechanical strength is qualified to structure hybrid scaffolds. In this study, nHA/PCL monofilament fibers with different mass ratios were fabricated through melt-spinning. Transmission electron microscope （TEM） was used to observe the aggregation between nHA parfides. Other characterizations including scanning electron microscopy （SEM）, attenuated total reflection Fourier transform infrared spectroscopy （ATR.FTIR） and X-ray diffraction （XRD） were done to discuss the morphology, components and crystallization of the nHA/PCL composite fibers, respectively. The influence of nHA/PCL mass ratio on the tensile properties and water contact angle of composite fibers was also studied. The SEM images show the homogeneous dispersion of nano partides in the polymer matrix. Besides, nHA content increases the tensile strength, initial modulus and hydrophillcity of the composite fibers under the premise of spinnability. This kind of fibers is strong enough to fabricate fiber assembly which may have potential application in bone tissue engineering.
