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Objective:To observe the intervention effect of Fengshi Qutong capsule on collagen-induced arthritis (CIA) in rats. Method:SD rats were randomly divided into normal group, model group, low, medium and high-dose Fengshi Qutong capsule groups (0.25, 0.5, 1 g·kg-1·d-1), and methotrexate group(0.2 mg·kg-1·d-1).Except for normal group, the other groups were immunized with type Ⅱ collagen and incomplete Freund's adjuvant to establish a CIA model. On the 1st day after the first immunization, the administration group was given intragastric administration, once a day, for 19 days; on the 8th day after the first immunization, the symptoms of joint swelling and malformation of the rats were observed, and the clinical scores and incidence of arthritis were evaluated. On the 19th day, micro-computed tomography and bone metrology were performed, and histopathological examination of inflammatory joints was performed,andsynovial inflammation,vasospasm, cartilage erosion and bone destruction by pathological severity scores, serum interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), vascular endothelial growth factor (VEGF),matrix metalloproteinase-3 (MMP-3) and receptor activator of nuclear factor kappa B ligand(RANKL)were detected by enzyme linked immunosorbent assay. Result:Fengshi Qutong capsule could improve the symptoms of inflammatory joint redness, swelling and deformity in CIA rats in a dose-dependent manner. Compared with normal group, clinical score and incidence, joint synovial inflammation, vasospasm, cartilage erosion and pathological score of bone destruction in joint group were significantly increased (PPPβ, TNF-α, VEGF, MMP-3 and RANKL in serum were increased (PPPPPPPβ, TNF-α, VEGF, MMP-3 and RANKL were significantly decreased (PPConclusion:Fengshi Qutong capsule can effectively alleviate the clinical symptoms and conditions of experimental rheumatoid arthritis in rats, reduce the incidence, and relieve the histopathology and imaging severity, while inhibiting the inflammatory cytokines.
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BACKGROUND: Preparing a scaffold with cartilage derived components and good initial mechanical strength is the direction of tissue engineering cartilage research. OBJECTIVE: To prepare porous acellular osteochondral scaffolds, and to explore their mechanical properties and cell compatibility. METHODS: Osteochondral bone from the porcine knee joint was taken, and then porous osteochondral scaffolds were made by laser microporation technology. Subsequently, the scaffolds were decellularized chemical methods. Scaffold structure was observed by scanning electron microscopy, and the compression modulus of the scaffolds was determined. Bone marrow mesenchymal stem cells were cultured in L-DMEM containing 10% fetal bovine serum (control group) and cultured in the medium extract of porous acellular osteochondral scaffolds (experimental group), respectively. Cell proliferation was detected by cell counting kit-8 method within 5 days of culture. Bone marrow mesenchymal stem cells were seeded on the porous acellular osteochondral scaffolds, and within 28 days of co-culture, cell growth was observed by hematoxylin-eosin staining and toluidine blue staining. RESULTS AND CONCLUSION: (1) Observation under scanning electron microscopy: The porous acellular osteochondral scaffolds had the smooth surface with evenly distributed pores. The pores of the scaffold extended longitudinally into the subchondral bone. (2) Mechanical properties: The average compressive modulus of porous acellular osteochondral scaffolds was 0.77 MPa, which was close to the compression modulus of the normal cartilage (1.15 MPa). (3) Cell counting kit-8 test: There were no differences in cell proliferation between the control and experimental groups at 1, 2, 3, 4 and 5 days of culture. (4) Cell-scaffold co-culture: A large amount of bone marrow mesenchymal stem cells were observed to be adherent to the scaffold after 1 day of culture through hematoxylin-eosin and toluidine blue staining. However, as time went on, a few cells adhered to the pore wall or grew into the pores at 7 and 21 days of culture. There were also some adherent cells but a large amount of cell masses formed in the pores at 28 days of culture. To conclude, the porous acellular osteochondral scaffold has good mechanical properties and cell compatibility.
ABSTRACT
Objective To develop a novel measurement system composed of micro-CT, mechanical loading device and digital volume correlation (DVC) technique, so as to measure the three-dimensional microstructural deformation field in bone tissue. Methods Uniaxial compression was applied on the specimen with the micromechanical loading device, and CT scans were also conducted while maintaining the same loads; then sequential CT images were matched and searched accordingly by DVC method to calculate the micro-displacement in the specimen along three directions before and after loading; repeated scanning of zero-displacement and rigid body translation were used to evaluate the accuracy and precision of the system. The three-dimensional distribution of displacement field in bovine cancellous bone was measured by the system. Results The result from repeated scanning of zero-displacement showed that the highest accuracy of measurement was performed in the loading direction and the precision was less than tenth of the CT resolution. The result of rigid body translation showed that the standard deviation was 0.001~0.002 μm. For cancellous bone specimen under the load of 600 N, the range of micro-displacement was 100.35~110.25 μm, with multilayer field distribution. Conclusions The accuracy and precision of this measurement system can meet the requirement of DVC method. It is proved that this system can be used for measuring the three-dimensional micro-deformation field in the cancellous bone and as a measurement platform for investigating the relationship between deformation distribution and structural response in bone tissue for the future research.