Biocompatible chitosan/polyethylene glycol/multi-walled carbon nanotube composite scaffolds for neural tissue engineering / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Carbon nanotube (CNT) composite materials are very attractive for use in neural tissue engineering and biosensor coatings. CNT scaffolds are excellent mimics of extracellular matrix due to their hydrophilicity, viscosity, and biocompatibility. CNTs can also impart conductivity to other insulating materials, improve mechanical stability, guide neuronal cell behavior, and trigger axon regeneration. The performance of chitosan (CS)/polyethylene glycol (PEG) composite scaffolds could be optimized by introducing multi-walled CNTs (MWCNTs). CS/PEG/CNT composite scaffolds with CNT content of 1%, 3%, and 5% (1%=0.01 g/mL) were prepared by freeze-drying. Their physical and chemical properties and biocompatibility were evaluated. Scanning electron microscopy (SEM) showed that the composite scaffolds had a highly connected porous structure. Transmission electron microscope (TEM) and Raman spectroscopy proved that the CNTs were well dispersed in the CS/PEG matrix and combined with the CS/PEG nanofiber bundles. MWCNTs enhanced the elastic modulus of the scaffold. The porosity of the scaffolds ranged from 83% to 96%. They reached a stable water swelling state within 24 h, and swelling decreased with increasing MWCNT concentration. The electrical conductivity and cell adhesion rate of the scaffolds increased with increasing MWCNT content. Immunofluorescence showed that rat pheochromocytoma (PC12) cells grown in the scaffolds had characteristics similar to nerve cells. We measured changes in the expression of nerve cell markers by quantitative real-time polymerase chain reaction (qRT-PCR), and found that PC12 cells cultured in the scaffolds expressed growth-associated protein 43 (GAP43), nerve growth factor receptor (NGFR), and class III β‍-tubulin (TUBB3) proteins. Preliminary research showed that the prepared CS/PEG/CNT scaffold has good biocompatibility and can be further applied to neural tissue engineering research.

Psoralen induces proliferation of rabbit endosteal mesenchymal stem cells and constructs cell-scaffold bone complex innonunionrepair / 中国组织工程研究

BACKGROUND: Psoralen is a plant estrogen, and a large number of studies have confirmed its role in promoting cell proliferation and differentiation. OBJECTIVE: To construct a cell-scaffold composite bone using psoralen, rabbit endosteal mesenchymal stem cells and polycaprolactone and to explore its effect on the treatment of rabbit nonunion. METHODS: (1) Rabbit endosteal mesenchymal stem cells were cultured and cultured until the third generation for each experiment. Passage 3 cells were seeded onto culture plates containing 50 mg/L bone morphogenetic protein 2 (positive control), 10-8, 10-7 and 10-6 mol/L psoralen (low-, middle-, and high-concentration psoralen groups) or the same volume of purified water (control group). The cell proliferation of each group was detected on the 3rd, 5th and 7th days after intervention using MTT method. (2) The three-dimensional polycaprolactone scaffold was added to the bottom of the cell culture plate, and rabbit endosteal mesenchymal stem cells were seeded into the scaffold at a density of 1×103 per well. Then, 10-6 mol/L of psoralen was added. Cell-scaffold composite bone was taken after 21 days of culture. (3) Animal models of radial nonunion were established in 27 New Zealand white rabbits, and were then randomized into experimental, scaffold and control groups followed by implantation of cell-scaffold composite bone, simple scaffold, and nothing, respectively. Pathological hematoxylin-eosin staining for observation of bone healing was performed at the 2nd, 4th, and 8th weeks after surgery. Healing of nonunion was observed on the X-ray films that were taken at the 4th week after surgery. RESULTS AND CONCLUSION: (1) Three concentrations of psoralen could induce the proliferation of rabbit endosteal mesenchymal stem cells. Compared with the control group, 10-6 mol/L psoralen exerted the strongest stimulation effect on rabbit endosteal mesenchymal stem cells (P 0.05). (2) Pathological hematoxylin-eosin staining of radial nonunion showed that the number of osteoblasts in the experimental group was higher than that in the scaffold and control groups (P < 0.05). (3) The X-ray films revealed bone healing in the experimental group, partial healing in the scaffold group and non-healing in the control group. Overall findings indicate that psoralen can promote the proliferation of rabbit endostealmesenchymal stem cells, and the effect is certainly related to the concentration of psoralen. Psoralen can be combined with rabbit endosteal mesenchymal stem cells and polycaprolactone scaffold to form composite bone, achieving good outcomes in the treatment of nonunion in animals.

Combined treatment using cell scaffold and human fibroblast growth factor for small soft tissue defects of digits caused by trauma / 中华整形外科杂志

Objective@#To assess the effect of combined treatment using cell scaffold and human fibroblast growth factor for small soft tissue defects of digits caused by trauma.@*Methods@#From May 2012 to September 2016, twenty cases of small soft tissue defect of digits were repaired with cell scaffold combined with recombinant human basic fibroblast growth factor. The average defect area was 2.5 cm2. Wounds were debrided and repaired with artificial dermis. Every 2 or 3 days the dressings were changed and the wounds were treated externally with fibroblast growth factor until cell scaffolds have been removed 3-4 weeks after surgery.@*Results@#The group of 20 cases was followed up for 2-24 months. Wounds were healed with satisfactory appearance and no recurrence of wound or obvious hypertrophic scar was observed. No obvious functional problem was found in interphalangeal motion.@*Conclusions@#The method of repairing wound with cell scaffold combined with human fibroblast growth factor is simple and it result in healing of wounds with high quality.It provides a new choice for repairing wound in digits.

The role of B-cell scaffold protein with ankyrin repeats 1 in collagen-induced arthritis / 中华风湿病学杂志

Objective To analyze the roles of B-cell ccaffold protein with ankyrin repeats 1 (BANK1) in collagen-induced arthritis (CIA) murine model and the correlation with disease severity.Methods CIA murine model were established and evaluated.In different disease stages,the serum levels of anti-C Ⅱ auto-antibodies and BANK1 were detected by electrochemiluminescence immunoassay(ELISA).Moreover,the expression of BANK1 mRNA in peripheral blood cells were detected by real-time polymerase chain reaction (PCR) and its correlation with clinical scores was analyzed.Then the percentage of BANK1 expression in B cells in spleen and draining lymph nodes were detected by flow cytometry and the level of BANK1 protein in spleen was detected by Western blotting according to the results afore mentioned.The data was analyzed by Statistical Product and Service Solutions (SPSS) Stastistics 21.0 and figures were made with Graph Pad Prism 6.Repeated measure ANOVA was used to assess differences between the two groups.Correlations were analyzed by Spearman correlation analysis.Linear regression analysis was done when a correlation was identified.Results The incidence of CIA was over 90％.The clinical scores of arthritic mice was positively correlated with the serum levels of anti C Ⅱ total IgG antibody (r=0.717 5,P ＜0.01),anti C] IgG2a antibody (r=0.675 3,P＜0.01) and anti C Ⅱ IgG2b antibody (r=0.889 4,P＜0.01) respectively.The BANK1 level in the serum and the BANK1 mRNA expression were significantly decreased in different disease stages in CIA mice when compared with normal mice.The negative correlation between the BANK1 mRNA expression and clinical scores (r=-0.485 4,P＜0.01) was observed.The percentage of BANK1 +CD19+ cells in spleen and draining lymph nodes and the level of BANK1 protein in spleen were reduced in CIA as well.Conclusion Along with the disease progress in CIA,BNK1 expression is declined,which weakens the negative regulation of BANK1 on B cells.This change goes hand in hand with the severity of arthritis.

Establishment of Metrigel-VEGF-SW982 complexes and application of the complexes in synovial sarcoma model in mice / 西安交通大学学报(医学版)

Objective To establish Metrigel-VEGF-SW982 complexes and use the complexes to produce animal models of synovial sarcoma so as to provide new ideas for establishing other models of soft tissue tumors. Methods After the SW982 cells were cultured and collected,they were resuspended with Metrigel,and VEGF was added.The suspension was seeded into transwell to establish the scaffold complexes of Metrigel-VEGF-SW982.The complexes were cultured overnight.Cryosections were made and HE staining was carried out to observe the cell scaffold complexes.We randomly divided 10 female SCID mice(4 week old)into scaffold group and control group. The mice in the scaffold group were transplanted with cell-scaffold complexes,and the control group with cell suspension.After 8 weeks,the success rate of modeling was compared between two groups.The mice were sacrificed and the tumors were obtained.HE staining was carried out to observe the histopathological features of tumors in both scaffold group and control group.Results The SW982 cells were cultured with Matrigel in a 3D way,which could simulate the growth condition of cells in vivo.Establishing synovial sarcoma animal model with cell scaffold complex could increase the success rate.The tumors in scaffold group had a larger volume,higher density of tumor cells and greater vascularization(P＜0.05).Conclusion Establishing synovial sarcoma animal model with Metrigel-VEGF-SW982 complex can greatly improve the success rate of modeling,which can provide basis for the study of synovial sarcoma.

Progress of researches on nano-scaffold material used in spine tissue engineering / 中国矫形外科杂志

With the rapid development and wide application of nano-techonology,the development of spine tissue engineering materials has been ushered into a brand field.Because of its unique effects of promoting cell adhesion,proliferation and function,nano-meterial will play more and more important role in the research on spine cord injury repair.

Effect of low intensity pulsed ultrasound on repairing bone defect by cell-scaffold complex composed by rabbit bone marrow stromal cells and ?-tricalcium phosphate / 中国矫形外科杂志

[Objective] To explore the effect of low intensity pulsed ultrasound(LIPUS)on the ability of repairing rabbit radius defect by cell-scaffold complex composed with bone marrow stromal cells(BMCs)and ?-tricalcium phosphate(?-TCP).[Method]Bone marrow of a rabbit was drawn and cultured by differentiation culture medium to harvest BMCs and the third generation BMCs were cultivated on ?-TCP for one week in vitro.Bilateral distal radial defects were made using a 1-mm saw in 20 mature New Zealand white rabbits.The cell-scaffold complexs stimulated by LIPUS were implanted in rabbit radial defects(cell-scaffold complexs without stimulation as control).All the rabbits were killed at 4 or 8 weeks after operation.The defect healing state was observed with X-ray and histological technic.The gray density of CA was analyzed by computer image analysis system.[Result]It was found that the callus in the experimental group grew more quickly and apparently than that in the control group.At 4 weeks after operation,there was significantly statistical difference(P0.05).Histological slices in the experimental group showed that the absorption,organization of hematoma,the formation of trabeculae and matrix preceded those in the control group.There were more fibroblast,osteoblasts and callus in the experimental group.[Conclusion]Cell-scaffold complex composed with BMCs and ?-TCP stimulated by LIPUS can repair bone defect more effectively than that without LIPUS stimulation at the early stage of healing,but the effect tend to decrease at the late stage.