Searchable abstracts of presentations at key conferences on calcified tissues

ba0004oc10 | (1) | ICCBH2015

Lack of PEDF within the bone matrix is associated with osteoidosis and abnormally high bone mineral content

Fratzl-Zelman Nadja , Schmidt Ingo , Roschger Paul , Roschger Andreas , Reich Adi , Glorieux Francis H. , Wagermaier Wolfgang , Fratzl Peter , Klaushofer Klaus , Marini Joan C. , Rauch Frank

Background and methods: Pigment epithelium-derived factor (PEDF) is a potent antiangiogenic factor, ubiquitously expressed and secreted in human tissues. Hypertrophic cartilage and osteoblasts express PEDF that binds to type I collagen and glycosaminoglycans in the extracellular matrix. Two rare forms of osteogenesis imperfecta (OI) with intact collagen synthesis are associated with PEDF deficiency. Histological observations revealed excessive osteoid formation and prolonged m...

ba0001pp33 | Bone biomechanics and quality | ECTS2013

Influence of the organic matrix of mineralized tissues on their dynamic mechanical properties assessed by scanning acoustic microscopy

Blouin Stephane , Puchegger Stephan , Klaushofer Klaus , Roschger Paul , Fratzl Peter

Mineralized tissues like bone, articular calcified cartilage or mineralized turkey leg tendon (MTLT) are build by a composite of hydroxyapatite nano-particles and organic matrix. In bone and MTLT the matrix is formed by collagen type-I, but in contrast to bone in MTLT the collagen is uniaxial orientated, while in cartilage the matrix consists of collagen type-II and proteoglycans.Composition/orientation differences were investigated by a new scanning aco...

ba0003pp19 | Bone biomechanics and quality | ECTS2014

Scanning acoustic microscopy reveals heterogeneity of mechanical properties due to collagen orientation in mice cortical bone

Blouin Stephane , Puchegger Stephan , Klaushofer Klaus , Roschger Paul , Fratzl Peter

The local mechanical properties of bone are influenced not only by the material chemical composition but also by the spatial arrangement of the component’s e.g. orientation of collagen matrix. However, not much is known about local elastic modulus variations in cortical bone. Our goal was to use acoustic imaging to map elastic properties of murine bone with a several microns resolution. Rodent long bones exhibit a permanent growth with endosteal/periosteal bone formation ...

ba0003pp22 | Bone biomechanics and quality | ECTS2014

Bone matrix mineralization is preserved during perimenopausal stage in healthy women

Misof Barbara , Roschger Paul , Recker Robert , Klaushofer Klaus

Menopause is accompanied by a decrease in bone mineral density which can be caused by a reduction in bone volume and/or degree of bone matrix mineralization. Both of them are suggested to contribute to the increased fracture risk in postmenopausal individuals. In the present work, we aimed for information whether a drop in bone matrix mineralization is occurring in the perimenopausal stage of women. For this purpose, we measured the bone mineralization density distribution (BM...

ba0003pp37 | Bone biomechanics and quality | ECTS2014

Bone matrix mineralization after sclerostin antibody treatment in a mouse model of osteogenesis imperfecta

Roschger Andreas , Roschger Paul , Kneissel Michaela , Rauch Frank

Children with osteogenesis imperfecta (OI) still suffer from frequent fractures, despite bisphosphonate treatment. Thus new therapeutic approaches are needed. Sclerostin is a protein that is thought to inhibit bone formation. Treatment with sclerostin antibodies (SclAB) increases bone mass in animal models and in clinical trials and may be a rational therapy for OI as well.Transgenic (TgOI) Col1a1Jrt/+ mice were gene...

ba0004oc4 | (1) | ICCBH2015

Increased bone matrix mineralization in treatment-naive children with Crohn's disease

Roschger Paul , Misof Barbara , Klaushofer Klaus , Rauch Frank , Ward Leanne

Background: Crohn’s disease (CD) is an inflammatory bowel disease which affects many organ systems including the skeleton. In children with CD, bone mineral density is frequently low. Bone metabolic abnormalities, including lower biochemical measures of bone turnover (NTX) as well as decreased bone formation indices at the tissue level have been reported. The aim of our study was to gain information on the bone matrix mineralization in CD.Methods: W...

ba0001pp41 | Bone biomechanics and quality | ECTS2013

Mechanical contrasts between osteons and interstitial bone measured by scanning acoustic microscopy

Fix Dmitri , Puchegger Stephan , Pilz-Allen Christine , Roschger Paul , Fratzl Peter , Weinkamer Richard

For a reliable assessment of bone’s material quality in a clinical environment, a fast way to measure the mechanical properties of bone is needed. The investigation of material heterogeneity and anisotropy resulting from bone remodeling and mineralization requires an imaging technique with micrometer resolution. Scanning acoustic microscopy (SAM) using high-frequency lenses allows measuring the stiffness of bone under wet conditions in a non-destructive way with this spat...

ba0001pp417 | Osteoporosis: treatment | ECTS2013

A case of atypical femoral fracture with abnormal cortical bone characterized by impaired mineralization and pyrophosphate accumulation

Shabestari Maziar , Eriksen Erik Fink , Roschger Paul , Paschalis Eleftherios , Diez-Perez Adolfo

Impaired bone material properties have been invoked as being responsible for the development of atypical femoral fractures (AFF) after long term bisphosphonate use. We therefore analyzed bone material properties in a bone biopsy obtained at the fracture site from an 88-year-old female with AFF, who had been treated with alendronate for 8 years. We used conventional histology, quantitative backscattered electron imaging (qBEI), and Raman spectroscopy (RS).<p class="abstext"...

ba0003oc1.3 | Phosphate metabolism, fracture repair and osteoarthritis | ECTS2014

Klotho deficiency impairs mineralization by vitamin D hormone-driven upregulation of osteopontin and pyrophosphate in bone

Murali Sathish Kumar , Roschger Paul , Zeitz Ute , Klaushofer Klaus , Andrukhova Olena , Erben Reinhold G.

Lack of Klotho, the co-receptor for the bone-derived hormone fibroblast growth factor-23 (FGF23), leads to a severe impairment in bone mineralization in mice. However, the mechanisms underlying the Klotho deficiency-associated defects in bone mineralization are still poorly understood. Here, we sought to elucidate the vitamin D independent role of Klotho in bone mineralization. To ablate increased vitamin D signaling in Klotho knockout mice (Kl−/−), we c...