Bone Abstracts

Chronic obstructive pulmonary disease (COPD) has been found associated with low areal bone mineral density and an increase in fracture rate. Previous histomorphometric findings revealed abnormally low cancellous bone volume and thin cortices. In the present work, we studied the same transiliac bone biopsy samples from n=19 COPD patients for cancellous (Cn.) and cortical (Ct.) bone mineralization density distribution (BMDD) based on quantitative backscatter electron im...

Bisphosphonates (BPs) including alendronate (ALN) are the most widely prescribed therapy for post-menopausal osteoporosis. Despite their overall excellent safety record and efficacy in reducing fractures, concerns have been expressed lately regarding potential detrimental effects due to prolonged bone turnover reduction, although no definite cause–effect relationship has been established to date. The purpose of the present study was to determine bone material quality by R...

Duchenne muscular dystrophy (DMD) causes progressive muscle weakness and loss of ambulation. While glucocorticoid (GC) therapy improves motor function, many boys sustain fractures due to osteoporosis. Recently, i.v. bisphosphonate (i.v.BP) therapy has shown promise in the treatment of DMD-related osteoporosis. At the same time, bone histomorphometry revealed lowered bone volume and significant reductions in bone formation pre-i.v.BP treatment, and a further drop after 2 years&...

Spatial distributions of major and minor chemical elements are supposed to change during tissue maturation and due to bone diseases. Previous studies suggested that osteocytes have the ability to interact with the bone matrix of their environment. For this interaction osteocytes make use of the big inner surface of the osteocyte lacuno-canalicular network (OLCN) in which they are accommodated. The aim of this study was to quantify spatial correlations between the elemental com...

We retrospectively analyzed the incidence of hip re-fractures in Austrian hip fracture patients devoid of anti-osteoporotic drug treatment, taking vs not taking proton pump inhibitors (PPIs).For 31,668 patients ≥50 years sustaining a hip fracture in Austria between July 2008 and December 2010, information on hip re-fractures with follow-up until June 2011 and on filed prescriptions of PPIs and anti-osteoporotic drugs between July 2007 and June 2011...

Deficiency of Cyclophilin B (CyPB) causes recessively inherited Type IX osteogenesis imperfecta, a moderately severe to lethal bone dysplasia. CyPB, encoded by PPIB, is an ER-resident peptidyl-prolyl cis-trans isomerase (PPIase) that catalyzes the rate-limiting step in collagen folding, and also functions as a component of the collagen prolyl 3-hydroxylation complex. We previously demonstrated in a Ppib−/− mouse model that CyPB PPIase activity r...

Objectives: Osteocytes play a major role in bone metabolism as mechanosensors, key regulators of osteoblast and osteoclast activity and of the mineral homeostasis. Therefore the assessment of osteocytes characteristics is important to understand bone pathology. We propose to study indirectly the osteocytes by performing quantitative backscattered electron imaging to quantify the sectioned osteocyte lacunae density and size in 2D on bone samples.Methods: ...

Objectives: FGF23 is expressed in clusters of osteocytes at the trabecular periphery suggesting that FGF23-expressing osteocytes are confined to specific basic multicellular units (BMUs) at the trabecular surface. Higher numbers of FGF23-expressing osteocytes are found in chronic kidney disease (CKD) patients with preserved skeletal mineralization indices. We thus combined immunohistochemistry and quantitative backscattered electron imaging (qBEI) to explore the hypothesis tha...

Objectives: Mice with a non-functioning vitamin D receptor (VDR mutants) develop severe secondary hyperparathyroidism, which can be rescued by a diet enriched with calcium, phosphate and lactose. In this work, we studied the effects of a low calcium challenge (CD), normal calcium (ND) and a calcium enriched rescue diet (RD) on the bone mineralization density distribution (BMDD) and osteocyte lacunae sections (OLS) in these mice.Methods: BMDD and OLS were...

Background and methods: A specific skeletal complication in children with CKD is growth impairment. The effects of recombinant human growth hormone (rhGH) therapy on bone turnover and bone material quality are not well understood. Bone matrix mineralization density distribution (BMDD) as assessed by quantitative backscattered electron microscopy (qBEI) is an important determinant of bone material quality and reflects bone turnover (average tissue age) and mineralization kineti...