BACKGROUND: The establishment of coculture system combined with physical factors and scaffold materials and the Induction of cytokines have become the focus of chondrogenlc differentiation of bone marrow mesenchymal stem cells. OBJECTIVE: To observe the effect of bone morphogenetic protein 7 combined with porous tantalum on chondrogenlc differentiation of bone marrow mesenchymal stem cells. METHODS: Bone marrow mesenchymal stem cells of Sprague-Dawley rats (provided by Beijing Huafukang Biology) were Isolated and cultured. Group Intervention: (1) in the experimental group, porous tantalum tablet was added, while In the control group, porous tantalum tablet was not added. At 5 days after culture, cell growth on the surface of porous tantalum tablet was observed by phalloidin staining. At 1, 3,5, and 7 days after culture, CCK-8 method was used to detect cell proliferation. (2) Group A was added with chondrocyte Inducer; group B with chondrocyte Inducer and bone morphogenetic protein 7; group C with domestic porous tantalum material and chondrocyte Inducer; group D with domestic porous tantalum material and chondrocyte Inducer and bone morphogenetic protein 7. At 7,14 and 21 days after culture, the levels of type II collagen, SRY type high mobility group protein and matrix metalloproteinase-13 secreted by cells In each group was detected by ELISA. Western blot assay was used to detect the expression of type II collagen, SRY type high mobility group protein and matrix metalloproteinase-13. This study was approved by the Animal Experimental Ethics Committee of North China University of Science and Technology. RESULTS AND CONCLUSION: (1) The phalloidin staining results showed that bone marrow mesenchymal stem cells grew well on and around the porous tantalum surface. (2) At 3 and 5 days after culture, the proliferation of bone marrow mesenchymal stem cells was slower In the experimental group than in the control group (P < 0.05). There was no statistical difference In cell proliferation between the two groups at 1 and 7 days (P > 0.05). (3) At 7,14 and 21 days, the expression of type II collagen and SRY high mobility group protein Increased gradually among groups A, B, C and D (P < 0.05). At 7 days, the expression of matrix metalloproteinase-13 decreased gradually among groups A, B, C and D (P < 0.05). At 14 days, matrix metalloproteinase-13 secretion of matrix in group A was highest compared with that in group B, group C and group D (P < 0.05), but there was no significant difference between groups B, C and D (P > 0.05). At 21 days, there was no significant difference among groups A, B, C and D (P > 0.05). (4) Western blot assay showed that at 7,14 and 21 days after culture, the expression level of type II collagen and SRY high mobility group protein Increased gradually In groups A, B, C and D (P < 0.05). At 7 days, the expression of matrix metalloproteinase-13 decreased gradually In groups A, B, C and D (P < 0.05). At 14 days, the expression of matrix metalloproteinase-13 was higher in group A than In groups C and D (P < 0.05), and higher In groups B and C than In group D (P < 0.05). At 21 days, the expression of matrix metalloproteinase-13 was higher In group A than In groups B, C and D (P < 0.05). No significant difference was found among groups B, C and D (P > 0.05). (5) The results showed that bone morphogenetic proteln-7 combined with domestic porous tantalum could Induce cartilage differentiation of bone marrow mesenchymal stem cells, facilitate the expression of type II collagen and SRY high mobility group protein, and Inhibit the expression of matrix metalloproteinase-13.

Objective Parkinson's disease( PD) is a common chronic neurodegenerative disease,with four major symptoms of resting tremor, muscle rigidity, slow motion and postural balance disorder?The pathogenesis of Parkinson's disease is still unknown?A large number of studies suggested that may be the result of the interaction of genetic factors,environmental factors,aging,immune factors,specifically involved in oxidative stress,mitochondrial damage,and other mechanisms?There were 50% patients characterized by tremors,tremor is the most difficult symptoms to treat of PD, but the mechanism is still under controversial, so it ’ s of great significance to understand the generation of PD tremor, which helps to promote the clinical treatment and diagnosis.

BACKGROUND:Previous studies have shown that home-made porous tantalum has non-toxicity and good biocompatibility, and can promote osteogenesis. Herein, we explore the mechanisms of tantalum-bone interface osseointegration.OBJECTIVE:To observe the morphological characteristics and expressions of integrin β1 and fibronectin on the interface between porous tantalum and bone tissues after implantation into the right rabbit femur, and to evaluate the biological mechanisms of tantalum-bone interface osseointegration.METHODS: Animal models of bilateral femoral condyle defects were made in Japanese big ear rabbits. Porous tantalum rod and allogeneic bone were respectively implanted into the left (experimental group) and right (control group) femur of rabbits. The animal specimens at the bone defect region were taken and made into paraffin sections and hard tissue sections at postoperative 2, 4, 8 weeks for morphological observation of new bone at the junction between the tantalum rod and host bone under light microscope, for osteogenic observation of the tantalum-bone interface under scanning electron microscope, and for immunohistochemical detection of integrin β1 and fibronectin expression.RESULTS AND CONCLUSION:Porous tantalum was bonded closely with the host bone. The loose and thick fibrous capsule was observed in the early stage and became thinner in the late stage shown by hematoxylin-eosin staining. The new bone was visible on tantalum-bone interface. Hard tissue slicing observation showed that the new bone was seen on the porous tantalum-bone interface, blood capillaries grew into the pores at postoperative 2 weeks and the pores were full of new bone tissues at postoperative 4 and 8 weeks. Under the scanning electron microscope, the osteoblasts appeared on the tantalum surface and in the pores at the early stage, and bone maturation and lamelar bone were seen at the late stage. The immunohistochemical results showed that the expression of integrin β1 in the experimental group was significantly lower than that in the control group at postoperative 2 weeks (P < 0.05), but the expression of fibronectin had no significant difference between the two groups (P > 0.05). In addition, there was a decline trend in the expression of integrin β1 and fibronectin atpostoperative 2, 4, 8 weeks. To conclude, the porous tantalum material is beneficial to enhance adhesion of osteoblasts on the surface and inside the micro-pores. Increased expression of integrin β1 and fibronectin on the tantalum-bone interface at early stage may promote early osteogenesis, while their decreased expression at bone maturing stage can promote osseointegration and bone remodeling.

BACKGROUND: At present, there is evidence that domestic porous tantalum has good biocompatibility and osteogenic properties, but the specific osteogenic mechanism and its effect on osteogenic factors are still unclear. OBJECTIVE: To observe the effects of domestic porous tantalum materials on the expression of collagen type I, tissue transglutaminase-2 and calcium-binding protein A4 in MG63 cells. METHODS: MG63 cells in logarithmic growth phase were inoculated onto 24-well plates and cultured in three groups: in blank group, conventional medium was added; in tantalum extract group, porous tantalum material extract was added; and in tantalum scaffold group, porous tantalum material and conventional medium were added. On 1, 3, 5, 7 and 9 days of culture, the cell proliferation of each group was detected by cell counting kit-8 method. On 5 days of culture, the levels of collagen type I, tissue transglutaminase-2 and calcium-binding protein A4 secreted by MG63 cells in each group were detected by ELISA. Western blot assay was used to detect the expression of three proteins in each group. RESULTS AND CONCLUSION: (1) With the prolongation of culture time, the number of cells in each group increased gradually. There was no difference in cell proliferation among the three groups at different time points (P> 0.05). (2) The secretory levels of collagen type I and tissue transglutaminase-2 in the tantalum scaffold group were significantly higher than those in the blank group and tantalum extract group (P < 0.05), while the secretion of collagen type I and tissue transglutaminase-2 in the tantalum extract group was significantly higher than that in the blank group (P < 0.05). The secretion of calcium-binding protein A4 in the tantalum scaffold group was significantly lower than that in the other two groups (P < 0.05). (3) The expression of collagen type I and tissue transglutaminase-2 protein in the tantalum scaffold group was significantly higher than that in the blank group and tantalum extract group (P < 0.05), while the expression of collagen type I and tissue transglutaminase-2 protein in the tantalum extract group was significantly higher than that in the blank group (P < 0.05). The expression of calcium-binding protein A4 in the tantalum scaffold group was significantly lower than that in the blank group and tantalum extract group (P < 0.05). To conclude, domestic porous tantalum materials could promote the secretion of collagen type I and tissue transglutaminase-2 by MG63 cells, and inhibit the secretion of calcium-binding protein A4.

BACKGROUND: Previous studies have demonstrated that the Chinese porous tantalum made in China has non-toxicity and good biocompatibility, which can promote osteogenesis. OBJECTIVE: To investigate the effects of transforming growth factor β1 on proliferation, cel cycle and secretion of osteoblasts on porous tantalum/MG63 osteoblast-like cel composites. METHODS: Passage 3 MG63 osteoblast-like cel suspension (1×109/L) was seeded onto the porous tantalum, then the cel composites were inoculated in the medium with 0, 0.5, 5 and 10 μg/L transforming growth factor β1, respectively. The proliferation of osteoblasts was detected by cel counting kit-8 assay at 1-13 days after inoculation; the cel morphology and ultrastructure observed by scanning electron microscope and transmission electron microscopy; and level of col agen type I detected by enzyme-linked immunosorbent assay. RESULTS AND CONCLUSON: 0.5, 5, 10 μg/L transforming growth factor β1 could promote the osteoblast proliferation, and cel proliferation in the 5 μg/L transforming growth factor β1 group was higher than that in the other groups; in the 5 μg/L transforming growth factor β1 group, laminated osteoblasts adhered on the surface and grew into inner of porous tantalum, which extended more pseudopodia toward the scaffold; osteoblasts-secreted matrix could cover the scaffold and numerous rough endoplasmic reticulum, free ribosomes, dense mitochondria, Golgi apparatus as wel as matrix vesicles could be found in the cytoplasm. In addition, the level of col agen type I in the 5 μg/L transforming growth factor β1 group was significantly higher than that in the other groups (P < 0.05). These results indicate that transforming growth factor β1 can promote proliferation, and col agen type I secretion of osteoblasts on porous tantalum/MG63 osteoblast-like cel composites, and the optimum mass concentration of transforming growth factor β1 is 5 μg/L.

Objective Articular cartilage injury is one of the most common orthopedic diseases with high morbidity and morbidity,especially in the elderly. Articular cartilage injury causes degenerative changes of articular cartilage, such as osteoarthritis, which can lead to disability, pain during joint movement and deformation of bone and joint. The prevalence of osteoarthritis accounts for 10% ～12% of the total population in the world. It is a common disease. The prevalence of osteoarthritis has increased to 49. 7% for the elderly aged over 65 years old ( Statistics of the World Health Organization ( who) in 2010 show that with the development of social aging and obesity and other adverse factors,these figures will continue to rise. It is known that osteoarthritis is related to aging,trauma,genetic susceptibility,obesity and inflammation,but the specific cause of osteoarthritis has not been fully identified, which leads to many obstacles in clinical treatment of osteoarthritis. At present,most of the clinical and research work in this field is focused on the restoration of cartilage trauma. In this review, we summarize and discuss the methods of cartilage defect repair,as well as the hot spots and directions of future research work.

Objective:Osteoarthritis is a degenerative disease with slow progress, which is caused by aging, obesity, trauma and other factors.It has a great impact on the daily life of middle-aged and elderly patients.Compared with traditional drug, protein and antibody therapies, stem cells are expected to radically change the medical treatment of osteoarthritis, because they have the ability to replace and repair tissues and organs such as osteoarthritis and joints, and have better homology and lower immune rejection.In different types of stem cells, mesenchymal stem cells originate from the mesoderm and can differentiate into different cells to form organs originating from the mesoderm lineage.In view of its ability to differentiate into other types of cells, MSCs have also been used to treat tissues and organs of ectodermal and endodermal lineages such as diabetes mellitus and Parkinson's disease.Whether MSCs can differentiate into lineages other than mesoderm lineages and the efficacy of treating organ diseases of ectoderm and endoderm lineages have been debated.This review will discuss the clinical features of osteoarthritis, the developmental origin and differentiation potential of MSCs, and the role of MSCs and scaffolds in the treatment of osteoarthritis.

Osteoarthritis (OA) is slow progressive disease with destruction of articular cartilage and hypertrophy of subchondral bone.The elderly are the most common patients,usually treated by joint surgery.OA patients often undergo total joint replacement.The risk andhigh cost of joint replacement prompt researchers to use multi-potential mesenchymal stem cells to repair full-thickness articular cartilage.Mesenchyma Stem Cells (MSCs) are stromal cells that can differentiate into bone,fat and chondrocytes.MSCs exist in bone marrow and fat.Bone Marrow Mesenchymal Stem Cells (BMSCs) can also be found in synovial joints.MSCs affect the progress of OA.MSCs can be isolated and proliferated in vitro and applied in clinical trials.Current clinical trials are still at an early stage.The primary purpose is to evaluate the safety,feasibility and effectiveness.This article reviews recent progress in clinical trials of MSCs repair of OA.

Objective:To investigate the expression of circ_0063865 in esophageal squamous cell carcinoma(ESCC)tissues and cells and its effect on the biological properties of the cells.Methods:The loop structure and stability of circ_0063865 were identified by Sanger sequencing, back-to-back primer validation and the ribonuclease R(Rnase R)tolerance assay.The expression of circ_0063865 was detected by RNA fluorescence in situ hybridization in an ESCC tissue microarray and its clinical relevance was analyzed.The expression levels of circ_0063865 in a normal esophageal epithelial cell line and ESCC cell lines were measured by real-time quantitative polymerase chain reaction(RT-qPCR). Cell counting Kit-8, the colony formation assay, the scratch assay, the transwell invasion assay and flow cytometry were used to detect the effects of circ_0063865 on cell proliferation, migration, invasion abilities and apoptosis, respectively.Results:The loop formation of circ_0063865 was verified by Sanger sequencing, back-to-back primer and Rnase R tolerance assays.The results of RNA fluorescence in situ hybridization showed that the mean fluorescence intensity of circ_0063865 expressed in ESCC tissues was significantly higher than in its paired paracancerous normal tissues( t=2.267, P<0.05). The expression of circ_0063865 was significantly associated with lymph node metastasis( χ2=4.356, P<0.05). The average overall survival time of patients with high circ_0063865 expression ESCC was lower than that of patients with low circ_0063865 expression ESCC.RT-qPCR results demonstrated that, compared with HEEC, circ_0063865 expression was elevated in ESCC cell lines( F=18.413, P<0.05). In addition, after circ_0063865 knockdown, the proliferation, migration and invasion abilities of KYSE-30 and KYSE-150 cells were significantly decreased, and the level of apoptosis was significantly increased(both P<0.05). Conclusions:The expression of circ_0063865 in ESCC is high, and changes in its expression are significantly correlated with lymph node metastasis.Additionally, circ_0063865 can promote the proliferation, migration and invasion of ESCC cells.