Bone Abstracts

see PP494....

The process of vascular calcification shares many similarities with that of skeletal mineralisation, and involves the deposition of hydroxyapatite crystals in arteries and cardiac muscle. However, the cellular mechanisms responsible have yet to be fully elucidated. BMP-9 has been shown to exert direct effects on both bone development and vascular function. In the present study, we have investigated the role of BMP-9 in vascular smooth muscle cell (VSMC) calcification. Murine V...

The process of vascular calcification shares many similarities with that of skeletal mineralisation, and involves the phenotypic trans-differentiation of vascular smooth muscle cells (VSMCs) to osteoblastic and chondrocytic cells within a calcified environment. Various microRNAs (miRs) are known to regulate cell differentiation, however their role in mediating VSMC calcification has yet to be fully understood.Murine VSMCs were cultured for up to 28 days ...

Increasing interest is focusing on the role of the FGF-23/Klotho axis in mediating vascular calcification. However, the underpinning mechanisms have yet to be fully elucidated. Murine VSMCs were cultured in calcifying medium for a 21-day period. FGF-23 mRNA expression was significantly up-regulated by 7 days (1.63-fold; P<0.001), with a concomitant increase in protein expression. mRNA and protein expression of both FGFR1 and Klotho were confirmed. Increased FGF-23...

Osteoclasts secrete acid and cathepsin K to dissolve the mineral and digest the organic matrix of bone, cartilage and dentine. The secretions are by necessity destructive and potentially harmful to the cell itself and are therefore trafficked through the cell in membrane bound vesicles. Secretion takes place over a specialised membrane compartment, the ruffled border, which is only present in resorbing osteoclasts. The ruffled border membrane and the vesicles in its vicinity h...

Osteoclasts are the only cell type capable of resorption of mineralised matrix such as bone or dentine. Resorbing osteoclasts form distinct membrane domains: the functional secretory, the basolateral and the ruffled border (RB) domains. The RB allows acidification of the resorption lacuna, exocytosis of osteolytic enzymes and uptake of degraded bone material, processes that require directed vesicular transport. Few studies have tried to classify the vesicles near the RB into s...

Evidence is unclear on the effect of vitamin D intake on vitamin D status in children.Objective: In a meta-analysis, investigate the effect of vitamin D supplements and/or fortified foods on vitamin D status, using the biomarker 25-hydroxyvitamin D (25(OH)D) in children 2–18 years.Methods: Eligible studies were randomized placebo-controlled trials, published in English, in children 2–18 years that compared vitamin D suppl...

Metatropic dysplasia (MD) was first described by Maroteaux et al. in 1966. Its name was derived from the Greek word metatropos which means ‘changing pattern’ because individuals with this diagnosis begin life with a short-limbed dysplasia and a long trunk with narrow chest, and over time their dysplasia becomes short-trunked due to progressive kyphoscoliosis1. It is now recognized that MD is caused by gain-of-function mutations in transie...

Gaucher’s disease is a glycolipid storage disorder caused by an autosomally inherited deficiency of the lysosomal enzyme glucocerebrosidase. The majority of patients with Gaucher’s disease develop abnormal bone remodelling with severe consequences, including osteonecrosis, bone crises, and osteoporosis related fractures. Although enzyme replacement therapy is effective at reversing many of the pathological consequences, and preventing further progression of this dise...

Objectives and method: We retrospectively reviewed records of current patients with osteogenesis imperfecta (OI) to identify those on risedronate, doses used and effects of treatment. BMD changes over time were calculated as difference between measurement before risedronate and at one year (including measurements −3–0 m and 10–14 m after starting risedronate respectively).Results: 219/296 (74%) patients with OI had received bisphosphonate...