ABSTRACT
BACKGROUND:Icariin can promote bone formation and inhibit bone resorption,but it is difficult to dissolve in water,and its bioavailability is very low in vivo.Therefore,a suitable carrier is essential to fully utilize the biological activity of icariin.OBJECTIVE:To prepare an icariin/β-tricalcium phosphate (β-TCP) composite scaffold and to characterize its biological characteristics.METHODS:Three-dimensional printing technology was utilized to prepare porous β-TCP scaffolds carrying nano zinc oxide,and the compressive strength of porous β-TCP scaffolds was detected before and after addition of nano zinc oxide.Water absorption and porosity of the porous β-TCP scaffolds were also measured.Ultrasonic emulsification solvent dialysis was performed to prepare icariin/poly(lactic-co-glycolic acid) (PLGA) microspheres,followed by the detection of water absorption and porosity.The porous β-TCP scaffolds and icariin/PLGA microsphere suspension were mixed to prepare icariin/β-TCP composite scaffolds.Microstructure observation of the composite scaffolds was done by scanning electron microscope,and meanwhile,water absorption and porosity were detected.The composite scaffold was then immersed into PBS,and icariin concentration in the supematant was measured at corresponding time points,based on which Icariin cumulative release curve was drawn.RESULTS AND CONCLUSION:(1) The porous microstructure of the porous β-TCP scaffold was regular,well distributed,and the connectivity was good.The pore spacing was about 600 μm.After addition of nano zinc oxide particles,the surface structure of the scaffold was more compact and the crystallinity was higher.(2) PLGA microspheres were spherical with a diameter of 1-4 μm,and the microspheres were uniform in size.(3) The maximum compressive strength of the porous beta tricalcium phosphate scaffold was (2.98±0.78) MPa,and increased to (8.95±0.29) MPa after addition of nano zinc oxide.(4) The water absorption rate and porosity were (25.09±0.96)％ and (66.93±2.84)％ for the porous β-TCP scaffold,(28.46±1.85)％ and (32.65±3.32)％ for the icariin/β-TCP composite scaffold,respectively.(5)The average encapsulation efficiency of the PLGA microspheres was (78.87±2.31)％,and the drug loading was (6.04±1)％.(6) The release amount of icariin could reach 52％ of the total amount at 16 days and 60％ of the total amount at 32 days.These findings indicate that the icariin/β-TCP composite scaffold has good mechanical properties and sustained-release performance.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the melatonin signaling transduction pathway in BMSCs from adolescent idiopathic scoliosis patients.</p><p><b>METHODS</b>Twenty-four volunteers aged 12 - 18 years were divided into two groups: AIS group was 15 and control group was 9. The human bone marrow anticoagulated by heparin was obtained from anterior superior iliac spine, and the BMSCs were isolated by density gradient centrifuge from the mononuclear cells, and then were cultivated and serial subcultivated in vitro. P3 cultures were analyzed by the flow cytometry to determine the surface antigens. P3 BMSCs were used to detect the melatonin signaling transduction pathway. The cellular cAMP was elevated using forskolin, and then the BMSCs were treated with melatonin to inhibit the cellular cAMP levels.</p><p><b>RESULTS</b>Mononuclear cells were cultivated and subcultivated to P3 culture in vitro, which were analyzed by the flow cytometry, and demonstrated that the expanded mononuclear cells expressed mesenchymal cell markers. The basal cAMP levels of the two groups were very low, after the stimulation of forskolin, cellular cAMP levels increased rapidly in all the patients, but after the stimulation of melatonin at physiological dose or even at pharmacological dose, there was no statistical difference of the inhibition of cAMP between AIS group and control (P > 0.05).</p><p><b>CONCLUSION</b>Melatonin signaling transduction pathway may be normal in BMSCs from AIS patients.</p>
Subject(s)
Adolescent , Child , Female , Humans , Male , Bone Marrow Cells , Metabolism , Case-Control Studies , Cells, Cultured , Melatonin , Metabolism , Mesenchymal Stem Cells , Metabolism , Scoliosis , Metabolism , Signal TransductionABSTRACT
<p><b>OBJECTIVES</b>To explore the clinical significance of the transverse thoracic pedicle diameters measurement and thoracic pedicles classification in thoracic adolescent idiopathic scoliosis patients.</p><p><b>METHODS</b>Thirty thoracic idiopathic scoliosis patients who were hospitalized during October 2008 and July 2009 and 20 non-scoliosis adolescents who were adopted during August 2008 and July 2009 were included in this study. Successive CT thoracic vertebrae scanning of all subjects were obtained. All participants' transverse pedicle diameters of the thoracic vertebrae were measured with the software of PACS Client. Classified the pedicle into 4 types according to the transverse pedicle diameters. In control group, the transverse pedicle diameters of bilateral thoracic vertebrae were compared using paired-t test. In AIS group, the transverse pedicle diameters of concave and convex side thoracic vertebrae were compared using paired-t test. The distribution of pedicle types were compared using Chi-Square test between the control group and AIS group.</p><p><b>RESULTS</b>The transverse pedicle diameters showed a decreasing trend from T(1) to T(4) followed by an increasing trend from T(5) to T(12) in both groups. The bilateral transverse pedicle diameters had no significant difference in the control group. The transverse pedicle diameters of the concave side at the apex of thoracic curve were found to be significantly thinner than those of convex side. The ratio of Type 4 was higher in thoracic adolescent idiopathic scoliosis patients than the controls, and the ratio of Type 1 was smaller in thoracic adolescent idiopathic scoliosis patients than the controls.</p><p><b>CONCLUSIONS</b>The thoracic pedicles in thoracic adolescent idiopathic scoliosis patients are often rather thinner. Preoperative CT measurement of thoracic pedicle in the treatment of idiopathic scoliosis is suggested helpful in deciding the correct strategy of pedicle screw insertion and decreasing the risk of clinically relevant neurovascular complications.</p>