Bi-functional titanium-polydopamine-zinc coatings for infection inhibition and enhanced osseointegration.

The ideal orthopedic implant coating is expected to both inhibit microbial infection and promote osseointegration. In this study, Zn ions were immobilized on a Ti substrate via a polydopamine (PDA) chemical surface modification to prepare Ti-PDA-Zn coatings. Scanning electron microscopy (SEM), atomic force microscopy (AFM), energy-dispersive X-ray spectroscope (EDS), X-ray photoelectron spectroscopy (XPS), contact analysis system, and inductively coupled plasma atomic emission spectrometry (ICP-AES) were used to analyze the morphology, composition, wettability, and zinc ions release of the coatings. The Ti-PDA-Zn coatings demonstrated excellent antibacterial activities in vitro against both Staphylococcus aureus and Escherichia coli. The coatings additionally displayed good biocompatibility, as confirmed by cytoskeletal observations and cell viability assays. Furthermore, the in vivo results confirmed the excellent antibacterial properties and improved osseointegration capability of the Ti-PDA-Zn coating in the presence of S. aureus. The present findings indicate that the Ti-PDA-Zn coatings prepared herein have potential application in orthopedic implantation.

PPAR-α Agonist WY-14643 Inhibits LPS-Induced Inflammation in Synovial Fibroblasts via NF-kB Pathway.

Osteoarthritis (OA), the most prevalent form of arthritis that results from breakdown of joint cartilage and underlying bone, has been viewed as a chronic condition manifested by persistence of inflammatory responses and infiltration of lymphocytes. Regulation of the inflammatory responses in synovial fibroblasts might be useful to prevent the development and deterioration of osteoarthritis. WY-14643, a potent peroxisome proliferator activator receptor-α (PPAR-α) agonist, has been described to beneficially regulate inflammation in many mammalian cells. Here, we investigate the potential anti-inflammatory role of WY-14643 in lipopolysaccharide (LPS)-induced synovial fibroblasts. WY-14643 greatly inhibited the production of NO and PGE2 induced by LPS. In addition, the mRNA expression of intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), endothelin-1 (ET-1), and tissue factor (TF) was significantly suppressed by WY-14643, as well as the secretion of pro-inflammatory cytokines including interleukin-6 (IL-6), IL-1ß, tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein-1 (MCP-1). Furthermore, the transcription activity and nuclear translocation of NF-kB were found to be markedly decreased by WY-14643, while the phosphorylation of IkB was enhanced, indicating that the anti-inflammatory role of WY-14643 was meditated by NF-kB-dependent pathway. The application of WY-14643 failed to carry out its anti-inflammatory function in PPAR-α silenced cells, suggesting the role of PPAR-α. These findings may facilitate further studies investigating the translation of pharmacological PPAR-α activation into clinical therapy of OA.

Comparative study of InterTAN and Dynamic Hip Screw in treatment of femoral intertrochanteric injury and wound.

The aim of this study is to compare the effects and complications of InterTAN nail versus Dynamic Hip Screw (DHS) in treatment of femoral intertrochanteric fractures. Between January 2006 and December 2013, a total of 75 patients with femoral intertrochanteric fractures were retrospectively reviewed. There were 16 cases of type A1, 51 cases of type A2, and 8 cases of type A3. 37 patients treated with InterTAN nail, and 38 with DHS. The clinic data of surgical trauma, postoperative function and complications were statistically compared in this study. This results indicated that 31 cases by InterTAN and 30 cases by DHS had obtained follow-up with mean time (11 ± 5.6) months. Operative time of InterTAN group is (23.1 ± 9.2) min, and of DHS group is (55.2 ± 14.5) min (P < 0.05). Intra-operative active blood loss is (70.1 ± 30.7) ml in InterTAN group, and (205.7 ± 40.7) ml in DHS group (P < 0.05). Fluoroscopy frequency of InterTAN group is (16.3 ± 4.4) times, and of DHS group is (25.1 ± 3.1) times (P < 0.05). Complications occurred in 3 cases (9.7%) in InterTAN group compared 6 cases (20%) in DHS group (P < 0.05). Two cases had hip varus in InterTAN group, and three cases in DHS group. One case had deep venous thrombosis (DVT) in InterTAN group, and one case in DHS group. In conclusion, InterTAN significantly reduce the operative time, fluoroscopy frequency, intra-operative active blood loss and postoperative complications. The InterTAN technical features make it applicable to the aged patient with variety of medical basic diseases and cases of osteoporotic and unstable fracture types.

[Establishment of an in vitro model of natural degeneration of lumbar endplate chondrocytes and expression of Sox9 therein].

OBJECTIVE: To establish an in vitro model of natural degeneration of lumbar endplate chondrocytes and explore the role and the expression change of Sox9 gene, an important gene in the differentiation and maturation of chondrocyte, in the process of natural degeneration of endplate chondrocytes. METHODS: The lumbar vertebrae of 35 SD rats were taken out to obtain the endplates. Endplate chondrocytes were isolated by enzyme digestion and cultured so as to establish an in vitro natural degeneration model of chondrocytes. The morphological appearances and biological characteristics of the chondrocytes of different generations were observed by HE staining, immunocytochemical staining and toluidine blue et cetera; RT-PCR was used to detect the mRNA expression of Sox9 gene and type II collagen in differential generations. RESULTS: The lumbar cartilaginous endplate chondrocytes of rat expressed collagen II, and it's phenotype and biological characteristics were similar to those of articular cartilage cells. When the cells were passaged to the forth or fifth generations they were fusiform and their proliferative speed decreased. Compared with the primary generation chondrocytes, the expression of Sox9 mRNA in the forth and fifth generation chondrocytes was markedly decreased (P < 0.05). And the mRNA expression level of type II collagen, regulated by Sox9 gene, decreased too (P < 0.05). The mRNA expression of Sox9 was positively correlated with the mRNA expression of type II collagen (r = 0.912, P < 0.05). CONCLUSION: A model of natural degeneration of lumbar endplate chondrocytes has been established successfully, thus providing a good cytological basis for the study of degeneration of lumbar endplate. Sox9 gene may play a role in the process of natural degeneration of endplate chondrocytes.