Bone Abstracts

Vertebral fractures (VF) defined by morphometric analysis of spine radiographs are the most common complication of osteoporosis. Those that come to medical attention, with symptoms such as back pain and kyphosis are termed clinical vertebral fractures (CVF) and account for significant morbidity and mortality. Although much progress was made in identifying loci for bone mineral density, the genetic determinants of CVF remain unclear. Here we present the initial results from a g...

Background: We identified a family with early onset X-linked osteoporosis and fracturesMethods: We performed whole exome sequencing of the X chromosome in three affected members. After discovering a putative pathogenic variant we performed Sanger sequencing of all exons of this gene in other members of this family and in 95 unrelated men suspected of OI type I without COL1A1/2 mutations. We also genotyped a SNP in this gene (minor allele frequency 0.02) ...

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...

Autogenous bone graft has been used in the treatment of a fracture, non-union, and bone defect. However, bone graft substitutes have been developed and used because of the limited amount or donor site morbidity of the autogenous bone graft. Many kinds of bone graft substitutes including osteoconductive materials and osteoinductive materials are used for improving bone healing. Osteoconductive materials help to provide a three-dimensional structure to support the ingrowth of th...

Objectives: To describe the incidence of vertebral fractures in steroid-treated children.Methods: Fractures were assessed prospectively each year for 3 years according to the Genant semi-quantitative method. Proportions of children with incident fractures were determined annually over the study period. To examine associations with baseline clinical factors, the 3-year total number of incident fractures was analyzed using multivariable Poisson regression....

Background: Elevated plasma homocysteine levels are a risk factor for osteoporotic fractures. Supplementation with vitamin B12/folic acid lowers homocysteine levels. This study aimed to determine whether vitamin B12/folic acid supplementation reduces osteoporotic fracture incidence in hyperhomocysteinemic elderly.Methods: B-PROOF is a double-blind, randomized, placebo-controlled trial including 2 919 participants aged ≧65 years with elevated homocyste...

Bisphosphonate treatment reduces fracture risk in women with postmenopausal osteoporosis. However, some patients have an inadequate response to treatment. Estradiol and sclerostin play an important role in bone metabolism. Sclerostin is an endogenous inhibitor of osteoblastic activity and estrogen deficiency increases osteoclast activity and bone resorption.We examined the influence of both measures on fracture incidence in postmenopausal osteoporosis in...

Osteocalcin, the neurotrophins BDNF/NGF and Oxytocin(Oxt) have pleiotropic effects on energy metabolism, bone mass, reproduction and brain functions suggesting a coordinated regulation. The carboxylated osteocalcin(Ost) acts on bone, while the uncarboxylated Ost shows hormone-like actions. NGF regulates female fertility elevating LH, Ost−/− mice show high LH in spite of decreased testosterone. BDNF/NGF-Oxt-Ost interactions was investigated by RT-PCR meas...

Bone is a complex tissue constituted by a mineral phase, hydroxyapatite, and an organic phase, mainly represented by collagen type I. Specialized cells are responsible for bone formation and remodeling. Osteoblasts represent the bone forming cells, osteocyte are the orchestrator of bone remodeling through regulation of the other bone cells activity, by functioning as endocrine cells and by acting as mechanosensor, and osteoclasts, the bone resorbing cells. Mesenchymal osteopro...

Objectives: Osteogenesis Imperfecta (OI) type XIV is a recessive OI form characterized by bone fragility, multiple fractures and growth retardation. It is caused by mutation in TMEM38B gene encoding the endoplasmic reticulum (ER) channel TRIC-B. This channel allows the transport of K+ across the ER membrane modulating Ca2+ flux. Defective ER Ca2+ impaires collagen type I synthesis, likely affecting the activity of ER enzymes involved in its post translational modification. To ...