Bone Abstracts

Proteoglycans are abundant and structurally complex bio macromolecules. They reside on the cell surface and are a major component of the extracellular matrix including bone. Defective formation of proteoglycans may case pleiotropic connective tissue syndromes including EDS-like and Larsen syndrome–like phenotypes.We report on a girl with disproportionate short stature and joint laxity with pes planus and radial head dislocation. She was previously a...

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...

Cole-Carpenter syndrome (OMIM 112240) is characterised by bone fragility, craniosynostosis, ocular proptosis, hydrocephalus and a distinctive facial appearance. Intelligence is reported to be normal. In 1986, Cole and Carpenter reported two unrelated infants with multiple fractures and deformities of bone, with a skeletal phenotype similar to severe osteogenesis imperfecta (OI). In addition, these patients also had proptosis, blue sclerae, hydrocephalus and a distinct facial g...

Objective: This study aimed to evaluate the efficacy of the treatment with pamidronate disodium (PD) with respect to the increase of bone mineral density (BMD) in patients with osteogenesis imperfecta (OI).Patients and methods: We evaluated nine patients (six boys) with OI (four with type III, four with type IV, one with type I) treated with PD from 4.68 to 7.92 years (mean±S.D.: 6.75±1.38 years). Intravenous PD was administered ...

Mutations in LRP5 cause a variety of phenotypes, including high bone mass and low bone mass disorders. In patients with high bone mass, different heterozygous mutations have been described, all of them clustering in a region including the binding pocket for DKK1 and sclerostin. The pathogenic mechanism is thought to be a gain-of-function mediated by an impaired inhibition of the canonical Wnt signalling pathway, thereby leading to increased bone modelling.<p class="abstext...

FGF-23 is a phosphate regulating hormone and its production may be stimulated by circulating levels of 1,25-dihydroxyvitamin D (1,25-(OH)2D). Teriparatide administration increases levels of 1,25-(OH)2D, however it is unclear whether this mediates changes in FGF-23 levels. The aims were i) to determine the effect of teriparatide treatment on circulating levels of FGF-23 and 1,25-(OH)2D and ii) to describe the time course of effect in postmenopau...

Osteoporosis and vertebral fractures are recognised complications of ankylosing spondylitis (AS) but the underlying causes are incompletely understood. Osteoprotegerin (OPG) is a decoy receptor for RANK-L and inhibits osteoclastogenesis. We have previously demonstrated that antibodies to OPG (OPG-Ab) are associated with osteoporosis and increased bone turnover in patients with autoimmune diseases. The aim of this study was to determine whether OPG-Abs were detectable in AS pat...

Although the fracture risk reduction under bisphosphonate treatment in osteoporosis is clinically well established, it remains understudied why the efficacy of bisphosphonate therapy is higher for the prevention of vertebral fractures compared to other fractures.Our aim was to investigate whether anti-resorptive therapy with alendronate would result in different regional variations of structural indices in the vertebral body. We investigated the microstr...

Mast cells (MCs) are pro-inflammatory sensor and effector cells of the immune system. MCs seem to play a role in bone metabolism, because patients with systemic mastocytosis develop osteoporosis. MCs are present in the fracture callus during bone healing, however, their function has not yet been investigated. Here, we examined the role of MCs in the inflammatory and repair phase during fracture healing.Male 12-week old MC deficient mice (Mcpt5-Cre R-DTA)...

Interleukin-6 (IL-6) plays an important role in bone metabolism and regulates fracture healing in a presently unknown process. In the fracture callus IL-6 expression is biphasic; it peaks during the inflammatory phase and again during intramembranous and endochondral ossification (Ai-Aql et al. 2008). Few studies using IL-6 knockout mice indicate that IL-6 might be crucial for bone healing (Yang et al. 2007). However, a generalized IL-6 knockout induces multi...