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The development of a bioactive nanocomposite for bone replacement has gained much interest in the field of bone grafting. In this study, a nano fluorapatite (n-FA)-poly(butylene succinate) (PBS) bioactive composite was fabricated using a co-solution method. The results showed that the n-FA-PBS composite had improved hydrophilicity, compressive strength and an elastic modulus, which were obviously higher than those of PBS alone. In addition, the n-FA-PBS composite could inhibit bacterial attachment, with the number of viable bacteria on the composite obviously lower than on pure PBS, indicating good antibacterial ability. Moreover, the attachment and proliferation of human mesenchymal stem cells (hMSCs) on the n-FA-PBS composite was significantly higher than on PBS, and the alkaline phosphatase (ALP) activity of hMSCs on the composite was expressed at significantly higher levels compared to PBS. Furthermore, the hMSCs showed intimate contact with the composite surface and the cells spread and grew significantly better on the composite compared to PBS. Therefore, incorporation of n-FA into PBS is a good way to prepare an inorganic-organic bioactive composite of a nano ceramic and a polymer, which supports cell attachment, proliferation and differentiation. The implantation of the n-FA-PBS composite into the femoral bone of rabbits confirmed that the new bone tissue could form on the composite surfaces, and the composite combined directly with the natural bone tissue without fibrous capsule tissue, showing good osteoconductivity. In short, the n-FA-PBS bioactive composite has good biocompatibility and bioactivity, and has potential application in bone regeneration.

Bioactive scaffolds of the m-BG–PLLA composite with excellent biocompatibility, degradability and osteogenesis, which could be promising implants for bone regeneration.

Bioactive and degradable scaffolds of nano magnesium silicate (n-MS)/zein (ZN)/poly(caprolactone) (PCL) ternary composites were prepared by 3D-printing method. The results showed that the 3D-printed scaffolds possessed controllable pore structure, and pore morphology, pore size, porosity and pore interconnectivity of the scaffolds can be efficiently adjusted. In addition, the apatite-mineralization ability of the scaffolds in simulated body fluids was obviously improved with the increase of ZN content, in which the scaffold with 20 w% ZN (C20) possessed excellent apatite-mineralization ability. Moreover, the degradability of the scaffolds was significantly enhanced with the increase of ZN content in the scaffolds.The degradation of ZN produced acidic products that could neutralize the alkaline products from the degradation of n-MS, which avoid the increase of pH value in degradable solution. Furthermore, the MC3T3-E1 cells responses (e.g. proliferation and differentiation, etc.) to the scaffolds were significantly promoted with the increase of ZN content. The in vivo osteogenesis of the scaffolds implanted the femur defects of rabbits was investigated by micro-CT and histological analysis. The results demonstrated that the new bone formation was significantly enhanced with the increase of ZN content, in which the C20 scaffold induced the highest new bone tissues, indicating excellent osteogenesis. The results suggested that the ZN in the ternary composite scaffolds played key roles in assisting bone regeneration in vivo. Fig. 1 TEM image (a) and EDS (b) of n-MS, and XRD (c) of n-MS and ZN, and XRD (d) of C0, C10 and C20 scaffolds.Fig. 3 SEM micrographs of C0 (a and b), C10 (c and d) and C20 (e and f) scaffolds under different magnification after immersed into SBF for 5 days, EDS (g) of C20 scaffold immersed into SBF for 5 days, and the change of ions concentrations with time (h) after C20 scaffold immersed into SBF.

In this study, we used microarray analysis to investigate the biogenesis and progression of intervertebral disc degeneration. The gene expression profiles of 37 disc tissue samples obtained from patients with herniated discs and degenerative disc disease collected by the National Cancer Institute Cooperative Tissue Network were analyzed. Differentially expressed genes between more and less degenerated discs were identified by significant analysis of microarray. A total of 555 genes were significantly overexpressed in more degenerated discs with a false discovery rate of < 3%. Functional annotation showed that these genes were significantly associated with membrane-bound vesicles, calcium ion binding and extracellular matrix. Protein-protein interaction analysis showed that these genes, including previously reported genes such as fibronectin, COL2A1 and β-catenin, may play key roles in disc degeneration. Unsupervised clustering indicated that the widely used morphology-based Thompson grading system was only marginally associated with the molecular classification of intervertebral disc degeneration. These findings indicate that detailed, systematic gene analysis may be a useful way of studying the biology of intervertebral disc degeneration.

Diabetic nephropathy (DN) is one of the major microvascular complications in diabetes. Podocyte injury such as slit diaphragm effacement is regarded as a determinant in the occurrence and development of albuminuria in DN. In this study, we examined the effect of hyperoside, an active flavonoid glycoside, on proteinuria and renal damage in a streptozotocin-induced DN mouse model at the early stage. The results showed that oral administration of hyperoside (30 mg/kg/day for 4 weeks could significantly decrease urinary microalbumin excretion and glomerular hyperfiltration in DN mice, but did not affect the glucose and lipid metabolism. Periodic acid-Schiff staining and transmission electron microscopy showed that glomerular mesangial matrix expansion and podocyte process effacement in DN mice were significantly improved by hyperoside. Further investigations via immunofluorescence staining, real-time reverse transcription polymerase chain reaction and Western blot analysis showed that the decreased slit diaphragm protein nephrin and podocin mRNA expression and protein levels in DN mice were restored by hyperoside treatment. Collectively, these findings demonstrated that hyperoside could decrease albuminuria at the early stage of DN by ameliorating renal damage and podocyte injury.

ECD increases pedicle screw accuracy, especially in T1-T10, and reduces insertion time and radiation in posterior adolescent idiopathic scoliosis.

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