In vitro and in vivo evaluation of the developed PLGA/HAp/Zein scaffolds for bone-cartilage interface regeneration.

OBJECTIVE: To investigate the effect of electronspun PLGA/HAp/Zein scaffolds on the repair of cartilage defects. METHODS: The PLGA/HAp/Zein composite scaffolds were fabricated by electrospinning method. The physiochemical properties and biocompatibility of the scaffolds were separately characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and fourier transform infrared spectroscopy (FTIR), human umbilical cord mesenchymal stem cells (hUC-MSCs) culture and animal experiments. RESULTS: The prepared PLGA/HAp/Zein scaffolds showed fibrous structure with homogenous distribution. hUC-MSCs could attach to and grow well on PLGA/HAp/Zein scaffolds, and there was no significant difference between cell proliferation on scaffolds and that without scaffolds (P>0.05). The PLGA/HAp/Zein scaffolds possessed excellent ability to promote in vivo cartilage formation. Moreover, there was a large amount of immature chondrocytes and matrix with cartilage lacuna on PLGA/HAp/Zein scaffolds. CONCLUSION: The data suggest that the PLGA/HAp/Zein scaffolds possess good biocompatibility, which are anticipated to be potentially applied in cartilage tissue engineering and reconstruction.

[Preparation and biocompatibility evaluation of osteochondral composite scaffold].

OBJECTIVE: To prepare osteochondral composite scaffold and study its biocompatibility in vitro. METHODS: The composite material of nano-HAP/collagen I was prepared, and the osteochondral scaffold was manufactured by combining nano-HAP, collagen I, and PLGA as the bone section and sodium hyaluronate and PLGA as the chondral section. The diameter, chemical composition and crystallinity of the nano-HAP/collagen I composite particles were assessed with TEM, FTIR and XRD, and the biocompatibility and cytotoxicity of the scaffold were evaluated using MTT assay by co-culturing bone marrow stem cells and the scaffold. RESULTS AND CONCLUSION: The osteochondral composite scaffold has good microstructure without obvious cytotoxicity, possesses good biocompatibility with bone marrow stem cells and is suitable as an osteochondral scaffold material.

Bis[dieth-yl(hy-droxy)ammonium] benzene-1,4-dicarboxyl-ate.

In the centrosymmetric title compound, 2C(4)H(12)NO(+)·C(8)H(4)O(4) (2-), two N,N-dieth-yl(hy-droxy)ammonium cations are linked to a benzene-1,4-dicarboxyl-ate dianion by a combination of O-H⋯O and N-H⋯O hydrogen bonds, which can be described in graph-set terminology as R(2) (2)(7). The crystal structure is further stabilized by C-H⋯O hydrogen bonds, leading to the fomation of a ribbon-like network.

[Effect of bone morphogenetic protein microspheres on biological behavior of rabbit bone marrow stem cells].

OBJECTIVE: To evaluate the effect of bone morphogenetic protein (BMP) on the biological behavior of bone marrow stem cells (BMSCs) of rabbits. METHODS: BMP was either enwrapped or not in the microspheres made of chitosan and sodium alginate, and the biocompatibilities of the composites were examined by means of cell culture. The BMSCs were cultured with the two kinds of microspheres respectively, and the cell extension rate, proliferation, alkaline phosphatase activity and Coomassie blue staining of the cells were assayed. RESULTS: Inhibition of BMSC proliferation did not occur in response to in vitro culture with the microspheres, but alkaline phosphatase activity and D(lambda) values of Coomassie blue staining increased significantly in the cells cultured with BMP microspheres. CONCLUSION: BMP can increase the osteogenic capacity of BMSCs in vitro with the microspheres made of chitosan and sodium alginate as the carrier.