Bone Abstracts

Farnesoid X receptor (FXR) is a member of the nuclear receptor superfamily, which functions as bile acid sensor controlling the bile acid homeostasis. We have investigated the role of FXR in regulating bone metabolism in vivo. We have identified expression of FXR in calvaria and bone marrow cells, which was gradually increased during osteoblastic differentiation in vitro. Deletion of FXR in vivo has resulted in significant reduction in bone mineral density by...

Mesenchymal cells alter and retain their phenotype during skeletal development through activation or suppression of signaling pathways. For example, we have shown that Wnt3a only stimulates osteoblast differentiation in cells with intrinsic osteogenic potential (e.g., MC3T3-E1 pre-osteoblasts) and not in fat cell precursors or fibroblasts (respectively, 3T3-L1 pre-adipocytes or NIH3T3 fibroblasts). Wnt3a promotes osteogenesis in part by stimulating autocrine production of the ...

Engulfment adaptor phosphotyrosine-binding (PTB) domain containing 1 (GULP1) is an adaptor protein involved in the engulfment of apoptotic cells via phagocytosis. Although GULP1 is widely expressed in various tissues, including the brain, muscle, testis, and bone, the function of GULP1 has not been well studied. Here, we investigated whether GULP1 plays a role in the regulation of bone remodeling and examined its expression in bone cells. Conditional Gulp1 floxed mice...

Study design: Prospective study.Objectives: The risk factors correlated with actual falls were assessed in patients with lumbar spinal stenosis.Materials and methods: In 201 patients (M:F 65:136) with symptomatic lumbar spinal stenosis, falls history within recent one year was investigated. The factors which were expected correlation with actual falls were evaluated together. Blood chemistry was performed to evaluate serum Vitamin ...

Growth plate cartilage is solely responsible for bone lengthening in children. Injury upon growth plate is often repaired by bony tissue which leads to bone growth defects such as limb length discrepancies or bone angulation deformity at later life. Earlier studies using an established rat growth plate injury model have identified a series of repair phases; inflammatory, fibrogenic, osteogenesis and remodelling repair phases. Currently, the cellular and molecular mechanisms in...

Objective: Growth of patients with cystic fibrosis (CF) and meconium ileus is frequently compromised. The aim of this prospective study was to evaluate body composition in this particular group of patients. We hypothesized that history of meconium ileus could predict suboptimal growth, bone, muscle and fat mass, irrespective of other prognostic factors for CF.Methods: CF subjects were investigated over a 3-year period. Their medical records were reviewed...

Objectives: Maximising peak bone mass (PBM) during growth is an essential part in the prevention of fractures and osteoporosis later in life. Two of the most important modifiable factors influencing PBM are diet and physical activity (PA). These factors can have either a direct or indirect effect on bone. For example, increasing PA would increase loads directly to the bone or cause muscle changes which would drive changes in bone. This study aimed to assess whether there was a...

Osteogenesis imperfecta (OI) is most commonly caused by a defect in the gene that produces type I collagen. Features include fractures and ligamentous laxity. Reduced muscle tone is often seen, which can result in gross motor delay in younger children.Dynamic elastomeric fabric orthoses (DEFOs or lycra garments) are widely used in children with low truncal muscle tone, have been shown to improve posture, and increase stability. There is no research in th...

Objectives: High resolution peripheral quantitative computed tomography (HR-pQCT) was used to evaluate bone quality and volumetric bone mineral density (vBMD). However, manufacturers only provide a standard protocol for adult but not for growing subjects. The aim of this study was to investigate the difference on measurement between two different HR-pQCT scanning protocols in adolescence with unfused growth plate.Methods: 27 boys and 26 girls aged 13&#15...

Objectives: Soft tissues, such as fat mass (FM) and lean mass (LM), play an important role in bone development but this is poorly understood in highly active youths. The objective of this study was to determine whether FM or LM is a stronger predictor of areal bone mineral density (aBMD) and hip geometry estimates in a group of physically active boys after adjusting for height, chronological age, moderate-to-vigorous physical activity (MVPA), FM, and LM....