Bone Abstracts

Fibrodysplasia ossificans progressiva (FOP; OMIM #135100) begins in childhood and leads to irreversible restriction of movement, functional impairment, and shortened life-span. Individuals with FOP develop progressive limitations in chest expansion, resulting in restrictive lung disease. Current management guidelines published in 2011 (1) highlight that Influenza may be a causative factor for FOP flare-ups, and can also cause potentially deadly cardiopulmonary complications, e...

Background: Hyperphosphatemic familial tumoral calcinosis (HFTC) is characterized by hyperphosphatemia and the formation of tumor-like extra-osseous calcifications. Tumors often necessitate surgical management although medical treatment may limit the need for surgical intervention. We present two cases of HFTC successfully managed with combination acetazolamide (ACTZ) and sevelamer carbonate.Case Report #1: A 5-year-old African boy with a loss-of-functio...

Objective: Rett syndrome (RTT) is an X-linked neurodevelopment disorder. More than 95% of RTT female have mutations in methyl-CpG-binding protein 2 (MECP2), whose protein product modulates gene transcription. Specific MECP2 mutations may lead phenotypic variability and different degrees of disease severity. It is known that low bone mass is a frequent complication of subjects with Rett syndrome. This study aimed to investigate if specific MECP2 mutations may affects the degree...

Introduction: Achondroplasia, the commonest skeletal dysplasia, is caused by specific variant(s) in the fibroblast growth factor receptor 3 (FGFR3) gene that cause abnormal spine, skull and limb bone growth. Surgical indications for foramen magnum stenosis in this population vary widely in the literature.Methods: We performed a retrospective analysis of patients with achondroplasia aged >20 years (n=33) in our regional skeletal dysplasia cli...

Sclerostin, a Wnt signaling antagonist encoded by the SOST gene, negatively regulates osteoblasts and inhibits bone formation. Mechanical loading, which induces bone formation, leads to a decrease in sclerostin levels. Recently, neutralizing antibodies against sclerostin were tested successfully for the treatment of osteoporosis in rodents. However, sclerostin is not the only signal involved in mechanotransduction. Therefore we investigated whether treatment with sclerostin an...

Receptor activity modifying proteins (RAMPs 1, 2 and 3) are a class of important accessory proteins that interact and regulate several G-protein coupled receptor (GPCR) activity by finely modulating ligand interaction and in some cases trafficking receptors to cell surface.Predominant roles of RAMPs include ligand selectivity in receptors for Calcitonin (CT) family of peptides that comprise calcitonin, calcitonin gene related peptide, amylin and Adrenome...

Objective(s): We aimed to determine the prevalence of osteoporosis and risk factors for bone demineralization in the Italian population.Material and methods: 3090 consecutive subjects were screened for osteoporosis by using calcaneal quantitative ultrasounds (QUS) in 16 Italian cities (women: 2635; men: 455) during the extension of the FIRMO study carried out in 2011 on about 7000 people. Anamnestic data were collected to assess the presence of recognize...

Introduction: Osteoporotic fractures are known to be costly to society but estimates tend to be based on small scale prospective studies. In the following we report national data for healthcare costs due to fractures in patients with osteoporosis.Study population and methods: All Danish residents aged 35+, mean age 70.5 years, 13% men, 27.3% prior major osteoporotic fracture, who began bisphosphonates for osteoporosis between 1/1997 and 12/2002 (n</e...

Bone is continuously remodeled to remove damage, to adapt to changes in mechanical demands and to regulate calcium homeostasis. The first aim is accomplished by coupled bone formation and resorption whereas adaptation requires sites of formation to differ from those of resorption. The regulation of circulating ions is achieved by a stochastic exchange of bone packets. Here, we investigated these different aspects of remodeling in healthy and ovariectomized (OVX) mice treated w...

Background: Proline and hydroxyproline account for ~25% of aminoacids in collagen., Prolidase (peptidase D (EC 3.4.14.9)), cleaves iminodipeptides with a C-terminal proline or hydroxyproline, playing a major role in collagen catabolism. Mice with prolidase deficiency (PD) present with varied phenotypes including reduced size compared to wild-type littermates. We measured structural and mechanical properties of bones in PD mice.Methods: Whole femurs from ...