Bone Abstracts

see PP173....

Up to now, most of standard methods for measuring inorganic phosphate (Pi) to determine phosphatase activity are based on coupled enzyme assays, colorimetric methods or conductance measurements. However, none of these methods can measure Pi, substrate and protein concentrations simultaneously, allowing direct kinetic determinations of phosphatase activity in cells in a single assay. Among the enzymes having a pyrophosphatase activity and releasing Pi...

Bone marrow is the main hematopoietic organ of adults. There, hematopoietic stem cells from which all hematopoietic lineages can be generated are preferentially homing. Importantly, bone provides niches for early B cell differentiation and survival of long-lived plasma cells that produced antibodies. Thus, that perturbing bone homeostasis might impact B cell function and antibody production is a highly relevant hypothesis for patients receiving antiresorptive drugs.<p clas...

Many pharmacological treatments have been developed in order to prevent or treat postmenopausal osteoporosis. There is not any study in the literature comparing long-term treatments of osteoporosis. The aim of this work was to studythe effects of long-term prevention treatment with zoledronic acid (ZA) and strontium ranelate (SrR) on bone microstructure in ovariectomized rats.Sixty 6-month-old female Wistar rats were used in this study and divided into f...

In clinical studies, denosumab (DMAb) administration up to 8 years is associated with continued increases in bone mineral density (BMD) and low fracture incidence despite persistently low bone turnover markers and limited iliac crest tetracycline labelling (Papapoulos 2013). We tested the hypothesis that, with persistently low bone remodelling, BMD increases may result from a non-remodelling dependent mechanism to accrue bone matrix. We examined the fluorochrome labelling patt...

Introduction: The effectiveness of intravenous pamidronate was assessed independently and in combination with corrective osteotomy surgery for lower extremity deformities in children with osteogenesis imperfecta.Methods: Orthopaedic treatment was conducted in 21 patients with OI (type I–ten patients, type III–11 patients), including 13 males and eight females with mean age 9.4±0.6. All patients received calcium supplements and active forms...

Multiple myeloma (MM) bone disease is characterized by lytic bone lesions that contribute to patient morbidity and mortality after patients are in complete remission. The mechanisms mediating this long-term osteoblast (OB) suppression are poorly understood. We hypothesized that MM cells induce epigenetic changes at the Runx2 promoter in preOB bone marrow stromal cells (BMSC). We demonstrated that Gfi1, a transcriptional repressor of Runx2 that is induced in B...

Clinical data suggest that the mTOR inhibitor everolimus may have bone protective effects in addition to its anti-tumor effects in women with ER+/HER2− metastatic breast cancer receiving hormone-ablative therapies. Based on these findings, we tested the hypothesis, whether everolimus exerts concurrent anti-tumor effects while protecting the skeleton in murine models. Thus, we assessed bone metabolism and anti-tumor effects in osteolytic cancer models upon exposure to eve...

Due to its huge socio-economic impact a better understating of osteoporotic fracture healing is crucial.Thirty-one female merino land sheep were randomly divided into four groups. (i) Untreated control-group (C, n=8); (ii) bilateral ovariectomy (OVX, n=7); (iii) OVX and calcium-deficient diet (OVXD, n=8); and (iv) OVXD and additional biweekly corticosteroid injections (OVXDS, n=8). Drill-hole defects (7.5 mm in diamete...

Objectives: Two important goals of the Rare Diseases Clinical Research Network Brittle Bone Disorders Consortium (RDCRN BBD) are i) to perform collaborative clinical research in brittle bone disorders including a longitudinal observational study driven by genotypic association and ii) to explore use of the PROMIS tool to provide valid quality of life (QOL) measures in individuals with Osteogenesis Imperfecta (OI). This work has been motivated by the fact that all current outco...