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The microstructure of the tissue has a very important determining effect on its performance. Herein, two calcium phosphate cement (CPC)/small intestinal submucosa(SIS) composites bionic bone scaffolds with different microstructures were fabricated by rolling or/ and assembling method. The microstructure, 3D morphology, the crystal phase and mechanical properties of the scaffolds were investigated by micro CT, XRD, FIIR, SEM and electronic universal testing machines respectively. The results showed that the pore size of all scaffolds are in the range of 100–400 µm, which are beneficial to cells growth, migration, and tissue vascularization. Their porosity and the specific surface area were 14.53 ± 0.76%, 8.74 ± 1.38 m 2 /m 3 and 32 ± 0.58%, 26.75 ± 2.69 m 2 /m 3 separately. The high porosity and the large specific surface area can provide a larger space and contact area for cells adhesion and proliferation. Meanwhile, compressive strength of the scaffolds soaked were 10 MPa and 27 MPa, about 1.2 folds and 3.2 folds of the original scaffolds, respectively. The results are derived from different microstructures of the scaffolds and chemical bonds between SIS and new phases (hydroxyapatite), and the scaffolds performance steadily increased at near the physiological conditions. Finally, biocompatibility of the scaffolds was evaluated by CCK8, bionic microstructure scaffolds are no cytotoxicity and their biocompatibility is favorable. Based on the microstructure, compressive strength and cytotoxicity of the scaffolds, bionic Harvarsin microstructure CPC/SIS composite scaffold is expected to turn into a scaffold with the excellent properties of real bone. [ABSTRACT FROM AUTHOR]

Since hydroxyapatite crystals are characteristically c-axis orientation on the surface of vertebrate long bone, c-axis orientation HAP biomimetic synthesized will find extensive applications in long bone growth, remodeling and fracture healing. In this paper, plate-like single-crystal HAP rods with c-axis orientation was successfully synthesized at bone mineralization conditions in vivo, with small intestinal submucosa membrane as biomineralization template. The samples were characterized by XRD, FIIR, SEM, TEM and EDS to unveil the phase structure, composition, morphology, and a plausible growth mechanism was proposed. The results showed that morphology of samples changed from flower-like to plate-like with extension reaction time from 1 day to 10 days. The plate-like HAp rods were single-crystal with c-axis orientation. A unit of plate-like HAP rods is about 70 µm and the width is 4 µm. Phase composition transformed from octocalcium phosphate and HAp biphase to HAp phase with very little octocalcium phosphate phase. Finally, biocompatibility of the samples was evaluated by CCK8. The samples without significant cytotoxicity conformed to the need for substitute materials of bone regeneration. [ABSTRACT FROM AUTHOR]

Objective To explore the ability of the biological composite materials. HA-glass coating/porous Zr02, inducing SD rat bone marrow mesenchymal stem cells to differentiate into osteoblasts in vitro, to find the ideal composite carrier of transplantated bone marrow mesenchymal stem cells and to investigate the security after transplantation, and to lay foundation for the fast recovery treatment of bone defect. Methods SD rat bone marrow mesenchymal stem cells were induced to differentiate by biological materials in vitro. Then cells were cultured for 14 days and 21 days. After dying with calcium-cobalt according to Gomori, Von Kossa staining, and immunohislochemical technology, the expression of alkaline phosphatase, calcium nodules, and type 1 collagen was detected. The changes of the expression of CD45, CD44, and CD90 in the cells before and after the induction were detected using flow cytometry. Results After 14-day induction in vitro, the cell morphology of SD rat bone marrow mesenchymal stem cells changed from long shuttle deformation cells to triangle or polygon cells, and there were clear boundaries between the cells. The expression of alkaline phosphatase was positive. After 21-day induction, dense and circular mineralized nodules appeared in cells, and the expression of type I collagen was positive. The boundaries between cells were blurred. According to the results of flow cytometry technology, the expression of CD44 was still positive, and the expression of CD45 was still negative. But the expression of CD90 transformed from positive to negative. The positive expression rate of cells decreased from 99.1% to 0- 29%. Conclusion Biological composite materials, HA-glass coating/porous ZiQ2 scaffolds, successfully induce SD rat bone marrow mesenchymal stem cells to osteoblasts. These materials can combine with bone formation through strong chemical bond, which can be used as bone defect tilling materials, and provide support for the formation of new bone, and play the conduction role in bone. [ABSTRACT FROM AUTHOR]

Background: Osteoporosis is a bone-incapacitating malady and it is characterized by obvious bone mass loss and bone microarchitecture deterioration. Current treatments for osteoporosis have many limitations, including the non-obvious therapeutic effect and long-term safety issues. Icariin is a pharmacologically active flavonoid glycoside, which shows potential application in treatment of osteoporosis. But its clinical application is limited by the inherent disadvantages such as poor water solubility, first pass effect after oral administration, and low bioavailability. Moreover, due to lack of targeting ability, icariin cannot accumulate at the local diseased region to provide early protection from fractures. To solve the application problems of icariin and enhance its therapeutic effects on osteoporosis, this work aimed to design a targeting drug delivery system of biomineral-binding liposomes (BBL) mediated by pyrophosphate ions. Results: Biomineral-binding liposomes enhanced the binding ability of liposomes with hydroxyapatite particles. It increased the serum level of alkaline phosphatase and reduced that of tartrate-resistant acid phosphatase 5b. Meanwhile, BBL increased the mechanical strength of femoral midshaft, preserving the trabecular bone microarchitecture. Moreover, BBL could initiate bone turnover/remodeling of rats with osteoporosis. Conclusions: This drug targeting delivery system of BBL loading with icariin showed more therapeutic advantages than the free icariin for the treatment of osteoporosis, which may be a kind of valid candidate in future osteoporosis therapy. [ABSTRACT FROM AUTHOR]

Calcium phosphate cement (CPC)/small intestinal submucosa (SIS) composite scaffold was prepared in this work by subtly stacking bio-inspired Haversian motifs (lamellar cylindrical motifs), which can form a structure similar to the Haversian microstructure in natural bones. SIS is rich in collagen and CPC can be easily transformed to hydroxyapatite into body fluids, making the components of the scaffold similar to natural bones. Porosity and specific surface area of the scaffold were 32 ± 0.58%, and 26.749 ± 2.691 m 2 /m 3 respectively. Pore size mainly ranges from 100 μm to 400 μm. The large specific surface area and the pore size are not only beneficial to cells attachment, growth, migration and revascularization, but also to the scaffold mineralization. After soaking for 6 h at 10× simulated body fluids, the compressive strength of the scaffold was about 27 MPa, 3 times more than that of the original scaffold. Thanks to the increasing compressive strength with holding the soaking time, the scaffold should be suitable for in vivo implanting and bone remodeling. [ABSTRACT FROM AUTHOR]