Research status and prospect of tissue engineering technology in treatment of atrophic rhinitis / 中国修复重建外科杂志

OBJECTIVE@#To review the research progress of the feasibility of a new treatment method for atrophic rhinitis (ATR) based on tissue engineering technology (seed cells, scaffold materials, and growth factors), and provide new ideas for the treatment of ATR.@*METHODS@#The literature related to ATR was extensively reviewed. Focusing on the three aspects of seed cells, scaffold materials, and growth factors, the recent research progress of ATR treatment was reviewed, and the future directions of tissue engineering technology to treat ATR were proposed.@*RESULTS@#The pathogenesis and etiology of ATR are still unclear, and the effectiveness of the current treatments are still unsatisfactory. The construction of a cell-scaffold complex with sustained and controlled release of exogenous cytokines is expected to reverse the pathological changes of ATR, promoting the regeneration of normal nasal mucosa and reconstructing the atrophic turbinate. In recent years, the research progress of exosomes, three-dimensional printing, and organoids will promote the development of tissue engineering technology for ATR.@*CONCLUSION@#Tissue engineering technology can provide a new treatment method for ATR.

Advance in functional bladder engineering / 生物医学工程学杂志

Bladder has many important functions as a urine storage and voiding organ. Bladder injury caused by various pathological factors may need bladder reconstruction. Currently the standard procedure for bladder reconstruction is gastrointestinal replacement. However, due to the significant difference in their structure and function, intestinal segment replacement may lead to complications such as hematuria, dysuria, calculi and tumor. With the recent advance in tissue engineering and regenerative medicine, new techniques have emerged for the repair of bladder defects. This paper reviews the recent progress in three aspects of urinary bladder tissue engineering, i.e., seeding cells, scaffolds and growth factors.

Development of Therapy for Duchenne Muscular Dystrophy / 中国修复重建外科杂志

Objective To review and summarize the latest development of the therapy for the Duchenne muscular dystrophy (DMD). Methods The recently-published articles related to the therapies for DMD were extensively reviewed and briefly summarized. Results The therapeutic approaches for DMD included the gene therapy, the cell therapy, and the pharmacological therapy.The gene therapy and the cell therapy were focused on the treatment for the cause of DMD by the delivery of the missing gene, the modification of the mutated gene, and the transfer of the normal cells including the stem cells, while the pharmacological therapy dealt with the downstream events caused by the dystrophin gene defect, slowed down the pathologic progress of DMD, and improved the DMD patient's life quality and life span, by medication and other factor treatments. Conclusion There is still no cure for DMD because of various difficulties in replacing or repairing the defected gene and of the multifaceted nature of the severe symptoms. Therefore, it is imperative for us to find out a more effective treatment that can solve these problems.

Experimental study on cryopreservation of seeding cells of tissue engineered tendons / 生物医学工程学杂志

This study sought to find out a good way for the cryopreservation of tendon seeding cells so as to facilitate the preparation of tissue engineering tendons as products. The related questions are how different factors affect cell survival rate at the procedure of preservation and whether cryopreservation affects seeding cells' biological characters as well as collagen secretive function. The results of experiment indicate that DMSO is a more effective cryoprotectant in cryopreservation of tissue engineered tendon seeding cells. Blood serum nourishment is very important in cell culture, preservation and treatment. The same sustenance after cryopreservation increases cell survival rate. In the process of cryopreservation, the concentration of cells is important to cell survival rate; cell survival rate will decrease when it is less than 1.0 x 10(6)/ml. In the process of cryopreservation, the cooling speed is also important to cell survival rate, slow cooling method achieves higher cell survival rate than does the rapid cooling method. Cryopreservation by use of 10%DMSO+15%FCS+75%DMEM does not affect seeding cells' collagen secretive function greatly and does not affect seeding cells' growth curve, cell cycle and chromosome mode obviously. The prescription of 10%DMSO +15%FCS+75%DMEM is suited for the cryopreservation of tendon seeding cells.

Observation of the morphological change during the adipogenesis differentiation of human bone marrow stromal cell / 中国康复理论与实践

@#ObjectiveTo study the variant differentiated phase of the human bone marrow stromal cell (MSC) during induced adipogenesis course by morphological observation.MethodsAfter proliferated in vitro, MSCs isolated from bone marrow of the female adults volunteers were cultured with the adipogenetic inducers for 6—30 days. Morphological changes of the cells were observed everyday under Olympus contrast phase microscopy, and some specimens were stained with Oil-red-O.ResultsMSC showed long spindle shape before inducing, and then changed gradually to oval or round shape and the figure enlarged simultaneously. There were specifically morphological changes with lipid droplet emergence under plasmalemma and confluence gradually to lipid drop during differentiated into the phase of immature and mature adipocyte.ConclusionIt is easy to detect the MSC differentiated into the phase of immature and mature adipocyte with the specific morphological change of lipid droplet, while in the phase of preadipocyte and adipoblast, there is no special morphological change, and it may need some specific markers to detect.

Characteristics of tenocyte adhesion to biologically-modified surface of polymer / 生物医学工程学杂志

In this study we examined the in vitro characteristics of tenocyte adhesion to biologically-modified surface of polymer. Polylactic-co-glycolic acid (PLGA) 85/15 films were prepared by a solvent-casting technique. Each film was adhered onto the bottom of a chamber. The film was precoated with poly-D-lysine (PDL), and then coated with serum-free F12 medium containing various concentrations of fibronectin (FN), type I collagen (CN I), and insulin-like growth factor1 (IGF-1). The monoclonal antibodies (to FN and to CN I) with various dilutions were used to inhibit attachment of tenocytes to surface precoated with FN or CN I. Human embryonic tendon cells (HETCs) and transformed human embryonic tendon cells (THETCs) were used as the seeding cells. The system used for the measurement of adhesion force was the micropipette aspiration experiment system. The micropipette was manipulated to aspirate a small portion of the tenocyte body by using a small aspiration pressure. Then the pipette was pulled away from the adhesion area by micromanipulation. The minimum force required to detach the tenocyte from the substrate was defined as the adhesion force. The results showed that modification of FN or CN I by precoating significantly enhanced attachment of tenocytes to surface of polymer (P < 0.05). As antibodies to FN or CN I were added to a polymer film precoated with FN or CN I, the adhesion force decreased significantly (P < 0.05). We concluded that the specific adhesion forces of tenocytes to extracellular matrix adhesion proteins (FN and CN I) had coordinated action and showed good dependence on their precoating concentrations, and were inhibited by the antibodies to these adhesion proteins. Films precoated with IGF-1 strongly accelerated the adhesion of tenocytes to polymer. These results indicate that the specific adhesion of tenocytes to polymer can be promoted by coating extracellular matrix adhesive proteins and insulin-like growth factor1. It is of great importance to construct tissue-engineered tendon.

Experimental studies on procedures and properties of natural derived scaffold materials of tissue engineered bone / 生物医学工程学杂志

To detect the properties of natural xenogeneic bone derived materials which were processed with different physical and chemical treatments, we made fully deproteinized bone(FDB), partially deproteinized bone (PDPB), partially decalcified bone(PDCB) from pig ribs. Their morphological features, constitute components and mechanical properties were examined by scanning electron microscopy, x-rays diffraction analysis, mechanical assay and so on. The results showed that FDB, PDPB and PDCB maintained natural network pore system. The ratios of calcium to phosphorus were 1.81, 1.74 and 1.50, and the protein contents were 0.01% +/- 0.02%, 22.41% +/- 0.83% and 35.75% +/- 2.12% respectively. The sequence of their mechanic strength was PDCB > PDPB > FDB. These data indicate that FDB, PDPB and PDCB possess natural network pore system. Their organic and inorganic component ratios and contents are different, so their mechanic properties are not alike. Additionally, more investigations will be necessary to detect the biocompatibility of the three different scaffold materials of natural derived bone.

A tissue-engineered strain scaffold for three-dimensional cell cultures / 生物医学工程学杂志

This article introduces a three-dimensional scaffold which is used to perform three-dimensional cell culture under mechanical stretch from the point of construction of tissue-engineered tissue. The composition, structure, surface characteristics, mechanical property, and cell compatibility of the scaffold have been studied by using surface chemistry and material mechanics testing methods. The results indicate that the polyvinyl alcohol (PVA) sponge, which is water-tolerant, coated with Poly-DL-lactic-co-glycolic acid (PLGA) possesses a good nature in appropriate surface feature, porosity, elastic recoil, and cell compatibility. These features provide wide options for using this scaffold to study the effects of mechanical stretch on cells maintained in three-dimensional culture to provide a three-dimensional matrix.

Experimental studies on histocompatibility of three bio-derived bones / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the histocompatibility of three bio-derived bones.</p><p><b>METHODS</b>After treatment with different physical and chemical method, three bio-derived bones, the composite fully deproteinized bone (CFDB), partially deproteinized bone (PDPB) and partially decalcified bone (PDCB) were implanted into rabbits. The toxicity, immune response and subperiosteum osteogenesis of CFDB, PDPB and PDCB were studied through gross observation, serum antibody measurement, evaluation of local cellular immune response and HE staining.</p><p><b>RESULTS</b>The study showed that CFDB, PDPB and PDCB had no toxicity. They could conduct peripheral tissue to grow into them and had no harmful effect on subperiosteum osteogenesis. They could also promote cartilage and osteoid tissue derived from periosteum to calcify to new bone, and combine with the peripheral bone. The degree of immune response caused by them was in the sequence of PDCB > PDPB > CFDB.</p><p><b>CONCLUSIONS</b>The three bio-derived bones, CFDB, PDPB and PDCB have good histocompatibility.</p>

Osteogenesis in transplantation of tissue engineered bone to repair segmental defect of long bone / 中华骨科杂志

Objective To investigate the ability of osteogenesis, repaired effects and possible mechanism of tissue engineered bone made in an approach of bionics as a transplantation biomaterial to repair a segmental defect of long bone. Methods HA/?-TCP was composed with PDLLA and then composed with rhBMP-2 and collagen of typeⅠ. The combined biomaterial was put in common culture with osteoblasts harvested from periosteum of rabbit and vascular endothelial cells from kidney of rabbit then transplanted this tissue engineered bone to total segmental periosteum-bone defect of 1.5 cm in the rabbits radius which were investigated 4, 8 and 12 weeks after operation respectively. Investigation of the bone defect was made by means of gross observation, X-ray examination, histology of HE and Masson staining, image pattern analysis, scanning electron microscopy, EDAX. Results In gross observation, the implantations were adhered to the host bone well in four weeks, the implantations was bony healed with host bone in eight weeks, and some of the implantations were replaced by new formation bone in 12 weeks. In histological examination of four weeks after operation, lamellar bone was found, and eight weeks after operation, implant was incorporated to host bone end by end through cortical bone, and new bone marrow was found to invade into the implant. Furthermore, the outer part of implant was completely substituted by new cortical bone 12 weeks after operation. In addition, the histological study pointed out that the new bone arranged in type of various bands which were in subsequent transition. There is significant difference between 4 weeks and 8 weeks, and 4 weeks and 12 weeks, but no significant difference between 8 weeks and 12 weeks of the quantity of new bone. The ratio of calcium to phosphorus in the transplants tended to approach that in the host cortical bone along with the period of time after operation. Conclusion Satisfied effects of remodeling appeared after this tissue engineered bone composed by bionics was transplanted to the segmental defect of long bone. The mechanism of bone regeneration was endochondral ossification.

REPAIR OF GROWTH PLATE DEFECTS OF RABBITS WITH CULTURED CARTILAGE TRANSPLANTA-TION / 中国修复重建外科杂志

Objective　To prevent early closure of growth plate and developmental deformities of limbs by allografts of cultured cartilages into growth plate defects of rabbits. Methods　Chondrocytes isolated from articular cartilage of 1-month rabbits formed cartilage after cultivation in centrifuge tubes. The cartilages cultured for two weeks were implanted into growth plate defects of proximal tibiae of 6-weeks rabbits. At 4th and 16th weeks, X-ray, histologic and immunohistochemical examination were performed. Results　The tibiae had no marked deformities after 4 weeks of operation. Histologic examinations showed that the defects were filled with cartilage. Immunohistochemical results of type Ⅱ collagen were positive. The tibiae with allografts of cultured cartilages had no evident deformities after 16 weeks of operation. Histologic examination showed nearly closure of growth plates. On the contrary, the tibiae on control side formed severe deformities and growth plate were closed. Conclusion　Allograft of cultured cartilages into growth plate defects may replace lost growth plate tissues, maintain normal growth of limbs and prevent developmental deformity.

Experimental studies on gradient degradation biomaterials combined with cultured tenocytes in vitro / 中华显微外科杂志

0.05),hints that the tenocyte's function was not disturbed. The DNA index of cells of GDBM group was 0.96 and 2.1% higher than the control group,indicating that the tenocytes grow and proliferate faster when being combine cultured on GDBM. Conclusion GDBM show good biocompatibility combined with tenocytes and they are promising extracellular matrix scaffold for cell transplantation in tendon tissue engineering.

Ethical Anglysis for Tissue Engineering / 中国医学伦理学

Objective To explore the medical ethical problens in the research of tissue engineering and their clinical application.Methods According to the technical route of tissue engineering ,including seeding cells.scaffold materials,implantation in body,ethical problems and their disposal were dissussed.Results Patient's rights to know the facts of test,efficacy and security of clinical application must be fully ensured during implantation of seeding cells and scaffold materials to human body.Conclusion In needs to formulate related standard of tissue engineered products and perfect politics and regulations.