Bone Abstracts

Osteoclasts are multinucleated giant cells derived from the monocyte/macrophage lineage in the presence of receptor activator of nuclear factor kappa-B ligand (RANKL) and colony-stimulating factor 1 (CSF1). The bone remodeling process in zebrafish is incompletely understood. Here we describe several methods to quantify bone formation and resorption using a zebrafish mutant that lacks functional colony stimulating factor 1a receptor (csf1ramh5/mh5). Mice deficient in...

Introduction: Recessive osteogenesis imperfecta (OI) is caused by mutations in genes encoding proteins involved in post-translational interactions with type I collagen. Types VII–IX OI involve defects in the collagen prolyl 3-hydroxylation complex, which modifies α1(I)Pro986. PPIB encodes CyPB, a complex component with PPIase activity and the major isomerase facilitating collagen folding. We investigated the role of CyPB in collagen post-translational modifications a...

Reduced availability of oxygen, i.e. hypoxia, could occur during disuse, bone development, and fracture. Cartilage tissue is avascular in nature and the microenvironment of cartilage is hypoxic. Hypoxic regulation of gene expression generally involves activation of the hypoxia-inducible factor (HIF) transcription pathway. Receptor activator of nuclear factor-kappaB ligand (RANKL) is an osteoblast/stromal cell derived essential factor for osteoclastogenesis. Hypoxia-induced enh...

Background: Hypophosphatasia is generally regarded as a disease of bone and teeth. Lack of Tissue Non-Specific Alkaline Phosphatase (TNAP) leads to an accumulation of inorganic pyrophosphate and the Vitamin B6 metabolite pyridoxal 5′-phosphate (PLP), a reduction in pyridoxic acid (PA) and increased PLP/PA ratio. Vitamin B6 deficiency in the brain impairs synthesis of neurotransmitters, and is a well-recognised cause of neonatal seizures. We have found no previous reports...

Hypoparathyroidism results in low bone turnover and increased bone mineral density (BMD). Replacing deficient PTH with rhPTH(1–84) has the potential to correct these skeletal abnormalities. To investigate the effect of rhPTH(1–84) on BMD and bone turnover markers (BTMs), data from two studies were assessed.REPLACE, a double-blind, multicenter, placebo-controlled study, randomized 134 patients with hypoparathyroidism to receive once-daily rhPTH(...

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Objectives: Low bone mineral density is highly prevalent in non-ambulant cerebral palsy and is associated with a high risk of fractures. In most cases these fractures occur with no or minimal trauma. Primary and secondary fracture prevention strategies differ between sites and countries. In order to inform these strategies we intend to complete a trial of Zoledronate in children with Cerebral Palsy. We hypothesize that Zoledronate treatment significantly increases bone mineral...

Objectives: To establish the average bone mineral density (BMD) and bone mineral content (BMC) in young male population from the different ethno-geographical groupsMaterials and methods: Estimations of the calcaneal BMD (g/cm2) and BMC (r), using on ALOKA-5.0 DXA machine among Indian (n=58) and Nigerian (n=72) male students (17–20 years), were done. The anthropometric program included body weight, height, shoulder and th...

It has long been known that osteoarthritis induces dramatic structural changes in subchondral bone. Studies on patients’ biopsies have also shown that the new sclerotic bone is hypomineralized and has decreased elastic modulus. Due to their amenability for genetic studies, murine models of OA are particularly important for drug target discovery. However, whilst osteosclerosis has been reported also in murine OA models, little is known about the compositional and mechanica...

Odanacatib (ODN), a selective and reversible cathepsin K inhibitor was shown to histomorphometrically reduce trabecular (Tb) and intracortical (Ic) bone remodeling while preserving endocortical (Ec) and stimulating periosteal (Ps) bone formation (BF) in monkeys. Here, we investigate the bone site specific mechanism of ODN on bone modeling (Mo) versus remodeling (Re)-based osteons. Rhesus monkeys (13–19 yrs, n=8–11/group) were ovariectomized and treated with ...