Bone Abstracts

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Relatively little is known about immediate consequences of continuing vs interrupting long-term bisphosphonate treatment. This report describes changes in bone turnover and BMD in a 1-year, dose-finding trial of the calcium-sensing receptor antagonist MK-5442 in postmenopausal, BP-treated women, randomized to continued alendronate 70 mg weekly, switch to placebo, or switch to MK-5442. Recruited women (n=526) had taken alendronate for ≥12 months and an oral BP fo...

Objectives: Creation of reference curves for areal bone mineral density (aBMD) and bone mineral content (BMC) with consideration of relevant anthropometric variables.Methods: Analysis of the dual-energy X-ray absorptiometry (DXA) data collected as part of the Bone Mineral Density in Childhood Study1, including 2012 boys and girls, 5–22 years old, with a total of 10 525 visits, resulting in aBMD and BMC observations at the lumbar spine, hi...

IκB Kinase β (IKKβ), a key component of NFκB signaling, plays an important role in bone disease and cancer. Genetic and pharmacological inhibition of IKKβ/NFκB signaling increase bone mass and protect against ovariectomy- and inflammation-induced bone loss. Here, we describe a previously unknown role of the IKKβ/FoxO3a axis in bone metastasis associated with breast cancer. We observed that IKKβ expression is prevalent in invasive breast ...

see P21....

Background: Vitamin D plays an important role in calcium and phosphate homeostasis. Circulating 25 hydroxyvitamin D [25(OH)D] is metabolised into its biologically active form 1,25-dihydroxyvitamin D [1,25-d(OH)D] by the actions of 1α hydroxylase, and into inactive 2metabolite 24,25-dihydroxyvitamin D [24,25-d(OH)D] by 24-hydroxylase. Recent studies suggest the production of 1,25-d(OH)D) from 25(OH)D is 24,25-d(OH)D dependent. Genetic mutations of CYP24A1 gene resulting in...

Parathyroid hormone (PTH) is used to stimulate bone formation in osteoporotic patients, however concerns have been raised about the quality of the matrix produced since lower levels of total matrix mineral have been reported in osteoporotic and fracture patients treated with PTH. High resolution synchrotron-based Fourier Transform Infrared Microscopy (sFTIRM) was used to determine mineral content in age-matched bone during anabolic PTH treatment, using the simplified lamellar ...

Introduction: Mitochondrial dysfunction is associated with several clinical outcomes including diabetes and myopathy and is implicated in the human aging process. We previously showed that the mitochondrial DNA point mutation mtDNA3243A>G is associated with lower BMD and altered bone structure. The aim of this study was to assess bone turnover markers in individuals with the mutation and controls.Methods: We recruited 45 patients (29 female, 16 male)...

Objectives: To determine if genetic variants associated with principal component-derived areal bone mineral density (aBMD) loading scores.Methods: Our sample comprised 1,293 children of European ancestry enrolled in the longitudinal Bone Mineral Density in Childhood Study (52% female). The participants completed up to 7 annual study visits. From dual energy X-ray absorptiometry scans, sex and age-specific aBMD Z-scores were calculated for total hip, femo...

Objectives: To assess lumbar spine (LS) BMD Z-scores and the prevalence of vertebral fractures using DXA lateral vertebral (VFA) assessment in children and adolescents with chronic illnesses on GCs.Methods: All children between the ages of 5 and 17 years with chronic non-malignant illnesses who were on GCs (intravenous or oral) for greater than 3 months duration were evaluated. Study participants were children attending the paediatric sub-specia...