Objective To investigate the effect of aureolysin （Aur） on staphylococcus aureus biofilm formation of dacron biomaterial surfaces under different Aur concentration. Methods Ninety dacron biomaterials were divided into 3 groups （group A, group IA, control group） with random number table （30 piece in each group）. Dacron biomaterials were put into vials contained staphylococcus aureus （105 CFU/ml） respectively; then Aur was added to make the concentration at 400ng/ml in group A, and group B at 80ng/ml. The thickness and number of staphylococcus aureus biofilm on the surfaces of dacron biomaterials of each group were evaluated by confocal laser microscopy and scanning electron microscopy after incubating 6h, 16h, 24h, 30h, and 48h. Results The thickness and number of staphylococcus aureus biofilm on dacron biomaterials surfaces increased significantly with time dependence in control group. The thickness and number of staphylococcus aureus biofilm in group A were less than those in group B and control group at each time points （P〈0. 05）. The thickness and number in group B were significantly decreased than those in control group （P 〈 0. 05）. Conclusion The study shows that Aur can effectively inhibit the formation of staphylococcus aureus biofilm on dacron biomaterials surfaces with dose dependence.
Objective To review the application of genipin for the modification of natural biomaterials as a crosslinking agent and progress in research. Methods Domestic and foreign literature on application of genipin for the modification of natural biomaterials as a crosslinking agent was thoroughly reviewed. Results Genipin is an effective natural crosslinking agent with a very low level of cytotoxicity compared with conventional synthetic crosslinking agents. Tissues fixed with genipin can maintain a high level of stability as well as resistance to enzymatic degradation. Conclusion Genipin is a promising substitute for conventional synthetic crosslinking agents, which has offered an alternative for modification of natural biomaterials for tissue engineering.
Objective To review and evaluate the extensive and further research and the application of the collagenbased biomaterials in the field of clinical medicine. Methods The clinical research and application of collagen-based biomaterials were comprehensively reviewed and evaluated on the basis of the up-to-date publications and our practical experiences in their studies and manufacturing. Results The following five aspects concerned with the collagen-based biomaterials were evaluated: biological property, quality control, formulation of substrate and clinical application, immunogenicity and clinical side effect, and potential of the market development. Conclusion Collgen-based biomaterials have a great potential and market space in their clinical application.
Objective To review research progress of corneal tissueengineering.Methods The recent articles on corneal tissue engineering focus on source and selection of corneal cells, the effects of growth factors on culture of corneal cells in vitro. The preparation and selection of three-dimensional biomaterial scaffolds and their b and weak points were discussed. Results The corneal tissue engineering cells come from normal human corneal cells. The embryo corneal cell was excellent. Several kinds of growth factors play important roles in culture, growth and proliferation of corneal cell, and incroporated into matrix.Growth factors including basic fibroblast growth factor, keratinocyte growth factor, transforming growth factor β1 and epidermal growth factor was favor to corneal cell. Collagen, chitosan and glycosaninoglycans were chosen as biomaterial scaffolds. Conclusion Human tissue engineering cornea can be reconstructed and transplanted. It has good tissue compatibility and can be used as human corneal equivalents.
OBJECTIVE: To study the feasibility of the formation of allogeneic tissue-engineered cartilage of certain shape in immunocompetent animal using the injectable biomaterial. METHODS: Fresh newborn rabbits’ articular cartilages were obtained under sterile condition (lt; 6 hours after death) and incubated in the sterile 0.3% type II collagenase solution. After digestion of 8 to 12 hours, the solution was filtered through a 150 micron nylon mesh and centrifuged, then the chondrocytes were washed twice with phosphate buffered saline (PBS) and mixed with the biomaterial to create a final cell density of 5 x 107/ml. The cell-biomaterial admixture was injected into rabbits subcutaneously 0.3 ml each point while we drew the needle back in order to form the neocartilage in the shape of cudgel, and the control groups were injected with only the biomaterial or the suspension of chondrocytes with the density of 5 x 10(7)/ml. After 4, 6, 8 and 12 weeks, the neocartilages were harvested to analyze. RESULTS: The new nodes could be touched subcutaneously after 2 weeks. In the sections of the samples harvested after 4 weeks, it was found that the matrix secreted and the collagen formed. After 6 weeks and later than that, the neocartilages were mature and the biomaterial was almost completely degraded. The cudgel-shaped samples of neocartilage could be formed by injection. In the experiment group, there was no obvious immune rejection response. On the contrary, there were no neocartilage formed in the control group. CONCLUSION: The injectable biomaterial is a relatively ideal biomaterial for tissue engineering, and it is feasible to form allogeneic tissue engineered cartilage of certain shape by injection in an immunocompetent animal.
OBJECTIVE To study the biocompatibility on bioactive glass ceramics (BGC) and polylactic acid (PLA) combined with cultured bone marrow stromal cells (BMSCs) in bone tissue engineering. METHODS BMSCs were cultured combined with BGC and PLA in vitro, and the morphological characters, cell proliferation, protein content, and alkaline phosphatase activity were detected. RESULTS: BMSCs could be attached to and extended on both BGC and PLA, and normally grown, proliferated, had active function. BGC could promote cell proliferation. CONCLUSION The results show that both BGC and PLA have good biocompatibility with BMSCs, they can be used as biomaterials for cell transplantation in tissue engineering.
Objective To observe the biocompatibil ity of self-assembled FGL peptide nano-fibers scaffold with neural stem cells (NSCs). Methods FGL peptide-amphiphile (FGL-PA) was synthesized by sol id-phase peptide synthesistechnique and thereafter It was analyzed and determined by high-performance l iquid chromatography (HPLC) and massspectrometry (MS). The diluted hydrochloric acid was added into FGL-PA solution to reduce the pH value and accordinglyinduce self-assembly. The morphological features of the assembled material were studied by transmission electron microscope (TEM). NSCs were cultured and different concentrations of FGL-PA assembled material were added with the terminal concentrations of 0, 50, 100, 200, 400 mg/L, respectively. CCK-8 kit was used to test the effect of FGL assembled material on prol iferation of NSCs. NSCs were added into differentiation mediums (control group: DMEM/F12 medium containing 2% B27 supplement and 10% FBS; experimental group: DMEM/F12 medium containing 2% B27 supplement, 10% FBS and 100 mg/L FGL-PA, respectively). Immunofluorescence was appl ied to test the effect of FGL-PA assembled material on differentiation of NSCs. Results FGL-PA could be self-assembled to form a gel. TEM showed the self-assembled gel was nano-fibers with diameter of 10-20 nm and length of hundreds nanometers. After NSCs were incubated for 48 hours with different concentrations of FGL-PA assembled material, the result of CCK-8 assay showed that FGL-PA with concentrations of 50, 100 or 200 mg/L could promote the prol iferation of NSCs and absorbance of them was increased (P lt; 0.05). Immunofluorescence analysis notified that the differentiation ratio of neurons from NSCs in control group and experimental group were 46.35% ± 1.27% and 72.85% ± 1.35%, respectively, when NSCs were induced to differentiation for 14 days, showing significant difference between 2 groups (P lt; 0.05). Conclusion FGL-PA can self-assemble to nano-fiber gel, which has good biocompatibil ity and neural bioactivity.
ObjectiveTo summarize the developments of oxygen-generating materials as biomaterials and its applications in tissue engineering. MethodsThe recent literature on oxygen-generating materials as biomaterials was extensively reviewed, illustrating the properties and applications of oxygen-generating materials in tissue engineering. ResultsOxygen-generating materials as biomaterials have good biocompatibility and degradability. It supports the cell adhesion differentiation and growth. It is used for repairing liver, pancreas, myocardium, and so on. After modification, oxygen-generating materials can be extensively used in tissue engineering. ConclusionOxygen-generating materials is a good biomaterial, which has a great potential applications in tissue engineering.
OBJECTIVE: From the point of view of material science, the methods of tissue repair and defect reconstruct were discussed, including mesenchymal stem cells (MSCs), growth factors, gene therapy and tissue engineered tissue. METHODS: The advances in tissue engineering technologies were introduced based on the recent literature. RESULTS: Tissue engineering should solve the design and preparation of molecular scaffold, tissue vascularization and dynamic culture of cell on the scaffolds in vitro. CONCLUSION: Biomaterials play an important role in the tissue engineering. They can be used as the matrices of MSCs, the delivery carrier of growth factor, the culture scaffold of cell in bioreactors and delivery carrier of gene encoding growth factors.
Objective To study the past, present and future of bone grafting. Methods Related l iterature on bone grafting in recent years was extensively reviewed. Results Bone grafting had a history over 300 years, a variety of bone grafting candidates including autografting, allografting, xenografting, synthetic and composite bone grafting had been util ized in cl inical orthopedics at present. But bone autografting and allografting represented the preferred alternatives for bone grafting.It would be important trend in bone grafting to fulfill the optimizing design of biomaterials and constructing composite bone substitutes with cells, factors and scaffolds. Conclusion The future bone grafting might be focused on how to achieve the goal of the rapid osseointegration as well as the physiological bone reconstruction.