Chikara Miyamoto

Effects of Insulin-Like Growth Factor I on Transforming Growth Factor β1 Induced Chondrogenesis of Synovium-Derived Mesenchymal Stem Cells Cultured in a Polyglycolic Acid Scaffold

The aim of this study was to demonstrate the induction of chondrogenesis by transforming growth factor (TGF)-β1 from synovium-derived mesenchymal stem cells in a three-dimensional polyglycolic acid (PGA) scaffold, and to evaluate the effects of insulin-like growth factor (IGF)-I on TGF-β1-induced chondrogenesis. Adult human synovial membranes were obtained from the knees of patients with osteoarthritis or rheumatoid arthritis. Cells were expanded in monolayers, seeded onto a PGA scaffold, and cultured for 4 or 8 weeks in chondrogenic medium containing TGF-β1 with or without IGF-I. As a control, the cells were cultured in chondrogenic medium without TGF-β1. The glycosaminoglycan content was quantified using dimethylmethylene blue dye-binding assay, and the DNA content was measured fluorometrically. Histological examination was also performed using safranin-O staining. The expression of mRNA for aggrecan and collagen type II was confirmed by RT-PCR. After 4 weeks of cultivation with TGF-β1, the cells differentiated to a chondrocytic phenotype, and these chondrogeneses were more potent when cultured for 8 weeks. The combination of IGF-I and TGF-β1 produced higher amounts of glycosaminoglycan than TGF-β1 alone at 8 weeks. In conclusions, chondrogenesis from human synovium-derived mesenchymal cells was identified, and IGF-I plays a role in maintaining the extracellular matrix in combination with TGF-β1.

Upregulation of Thrombospondin 1 Expression in Synovial Tissues and Plasma of Rheumatoid Arthritis: Role of Transforming Growth Factor-β1 toward Fibroblast-like Synovial Cells

Objective. To investigate the role of thrombospondin 1 (TSP-1) in RA. Methods. Expression of TSP-1 in synovial tissues was determined by immunohistochemistry. Expression of TSP-1 in rheumatoid fibroblast-like synovial cells (FLS) was investigated by quantitative real-time PCR and ELISA. Correlations among the plasma TSP-1 and other variables in patients with RA were examined. Results. Expression of TSP-1 was increased in rheumatoid synovial tissues. Transforming growth factor-β1 (TGF-β1) clearly increased TSP-1 expression in FLS on both mRNA and protein levels. Changes in plasma TSP-1 were associated with those in 28-joint Disease Activity Score-erythrocyte sedimentation rate and plasma TGF-β1. Conclusion. TSP-1 might be critically involved in the disease process of RA through the TGF-β1/TSP-1 axis.

Total Hip Arthroplasty Using the S-ROM-A Prosthesis for Anatomically Difficult Asian Patients

Background. The S-ROM-A prosthesis has been designed for the Asian proximal femur with a small deformed shape and narrow canal. In this study, the clinical and radiological results using the S-ROM-A prosthesis for Japanese patients with severe deformity due to dysplasia and excessive posterior pelvic tilt were examined. Methods. 94 hips were followed up for a mean of 55 months, with a mean age at surgery of 61 years. The primary diagnoses were 94 coxarthritis cases, including 51 dysplasia and 37 primary OA, 1 avascular necrosis, 2 traumatic arthritis, and 3 Perthes disease. Thirty-one hips had been treated with osteotomy of the hip joints. Preoperative intramedullary canal shapes were stovepipe in 23 hips, normal in 51 hips, and champagne-flute in 5 hips. The maximum pelvic inclination angle was 56°. Results. The mean JOA score improved from 46 points preoperatively to 80 points at final follow-up. On radiological evaluation of the fixation of the implants according to the Engh classification, 92 (97%) hips were classified as “bone ingrown fixation.” Conclusion. In primary THA, using the S-ROM-A prosthesis for Asian patients with proximal femoral deformity, even after osteotomy and with posterior pelvic tilt, provided good short- to midterm results.