The impact of collagen sponge composite bone marrow mesenchymal stem cells (BMSCs) in inducing interbody fusion.

OBJECTIVE: To assess the effectiveness of bone mesenchymal stem cells (BMSCs) in the induction of interbody fusion. PATIENTS AND METHODS: The 3rd generation BMSCs were seeded on collagen sponge scaffold and cultured in osteoblast induction medium for 3 weeks to prepare cell-scaffold complex. Thirty patients were randomly divided into three groups to establish the L4/L5 interbody fusion model. The cell-scaffold complex was implanted in the intervertebral space in group I, the collagen sponge scaffold was implanted in group II, and the autologous iliac crest spongy bone was implanted in group III. Palpation, radiography, micro-CT, and histology were performed on the 12th weeks after operation to evaluate osteogenesis and spinal fusion. RESULTS: BMSCs differentiated into osteoblasts in the cell-scaffold complex after osteogenic induction for 3 weeks. The spinal fusion rates in group I, II, and III were 40%, 0%, and 70%, respectively. Micro-CT and histological examination showed mature bone marrow and trabecular bone formation in the fusion segments. The new bone was integrated with the upper and lower vertebral body. The bone trabecula in group III was stronger than group I. The surgical segments in group II was scar tissue without collagen sponge residue. CONCLUSIONS: BMSCs can induce osseous fusion in the lumbar vertebra.

Investigation for the role of CTX-III and microRNA-98 in diagnosis and treatment of osteoarthritis.

OBJECTIVE: Osteoarthritis is a joint degeneration and proliferative inflammatory disease caused by obesity, joint deformities, trauma, and other factors. C-terminal collagen (CTX) is associated with cartilage degradation, and healthy cartilage state is one of the factors that affect osteoarthritis. microRNA-98 (miRNA-98) plays a role in inflammation. This study aims to investigate the levels of CTX-III and miRNA-98 in patients with osteoarthritis and their potential clinical usage. PATIENTS AND METHODS: Osteoarthritis was diagnosed according to the inclusion and exclusion criteria for osteoarthritis. Patients with osteoarthritis admitted to Jining No. 1 People's Hospital and healthy volunteers were included in this study. ELISA and Western blot analysis were used to detect levels of type III collagen CTX (CTX-III). Real time PCR was used to measure levels of miRNA-98 in the serum of both patients and healthy volunteers. RESULTS: Levels of CTX-III protein in osteoarthritis patients were significantly higher than that of healthy volunteers (p = 0.0013). Levels of miRNA-98 in the serum of osteoarthritis patients were significantly higher compared to that of healthy volunteers (p = 0.0065). After treatment, levels of CTX-III protein and serum miRNA-98 in patients with osteoarthritis were significantly decreased (p = 0.014, p = 0.021). Levels of CTX-III protein and serum miRNA-98 in patients with osteoarthritis were significantly higher compared to that of healthy volunteers (p = 0.0013). CONCLUSIONS: Both of the CTX-III and microRNA-98 are potential diagnostic indicators for the osteoarthritis.

MicroRNA-26b inhibits osteosarcoma cell migration and invasion by down-regulating PFKFB3 expression.

MicroRNAs regulate target gene expression and are involved in cell proliferation, apoptosis, differentiation, tumor invasion, and cancer stem cell regulation, among other processes. MicroRNA-26b (miR-26b) is closely related to tumor occurrence and development. In this study, we analyzed miR-26b expression in osteosarcoma tissue, its effect on Saos-2 osteosarcoma cell proliferation and invasion, and its relationship with 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) expression. Osteosarcoma tissue was obtained from surgical patients and normal tissue adjacent to the tumor was used as a control. Real-time polymerase chain reaction was applied to detect miR-26b expression in cancer tissue and normal tissue. A vector expressing miR-26b was constructed and transfected into Saos-2. An MTT assay, cell invasion assay, and scratch experiment were used to analyze the effect of miR-26b on Saos-2 cell proliferation, invasion, and migration abilities. Western blotting analysis was performed to investigate the role of miR-26b on PFKFB3 expression. miR-26b expression in normal tissue was 7.55-fold higher than in osteosarcoma tissue (t = 10.20, P = 0.006). Compared with control tissue, miR-26b significantly inhibited osteosarcoma proliferation, migration, and invasion (P < 0.05). Western blotting results revealed that PFKFB3 protein expression decreased in Saos-2 cells after transfection with miR-26b. miR-26b was down-regulated in osteosarcoma tissue. miR- 26b may inhibit osteosarcoma cell proliferation, migration, and invasion by regulating PFKFB3 protein expression. miR-26b may have a tumor suppressor role in tumor occurrence and development.

Does DsbA have chaperone-like activity?

DsbA showed chaperone-like activity similar to but weaker than that of protein disulfide isomerase in increasing reactivation and decreasing aggregation during the refolding of guanidine hydrochloride-denatured D-glyceraldehyde-3-phosphate dehydrogenase and rhodanese. The fact that both enzymes are devoid of disulfide bonds indicates the independence of the chaperone-like activity of DsbA from its thiol-protein oxidoreductase activity. The increased reactivation of D-glyceraldehyde-3-phosphate dehydrogenase by DsbA can be suppressed with increasing concentrations of a peptide of 21 amino acid residues, suggesting that the peptide binding ability of DsbA is responsible for its chaperone-like activity.