Bone Abstracts

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...

Bone is a tough composite material, comprised of a compliant collageneous matrix, brittle apatite mineral crystals and a suite of non-collageneous proteins (NCPs). Bone material properties depend on these components, and their interactions at the mineral-collagen interface. ‘Bone mineral density’ (BMD), a parameter used to predict fracture risk, is routinely quantified by DEXA. Previous studies used ex vivo emu tibiae as a model to test the effect of organic...

Adaptive responses of the skeleton to loading changes architecture and physical properties in order to optimise strength for function. However, bone is subjected to many local and circulating osteotropic factors, most acting on G-protein coupled receptors. Receptor activity modifying protein-3 is a single trans-membrane domain receptor accessory protein, which aids in trafficking of calcitonin and calcitonin-like receptors to the cell surface and changes ligand selectivity. As...

An IgM monoclonal gammopathy (MGUS) is often the first sign of a lymphomonocytic B-lymphoma (Waldenström macroglobulinemia-WD). Osteolytic lesions can occur in B cell malignancies (WD, hairy cell leukemia, LLC\..) but are less frequent than in myeloma. In addition, bone remodeling in WD is poorly understood. However, an osteoporosis is often observed in MGUS patients. We studied a series of bone biopsies performed in patients with an IgM gammopathy by histomorphometry, mi...

Proton pump inhibitors (PPIs) are a class of drugs particularly used in gastric disorders. They promote a decrease on gastric acid secretion by inhibiting the H+/K+ ATPases. Osteoclasts are cells specialized in bone resorption by H+ translocation to the bone surface. Thus, PPIs might be regarded as potential tools to modulate osteoclast resorption activity, particularly in conditions that are associated with a hyperactivation of osteoclasts, li...

Hydroxyapatite (HA) has been widely used as a biocompatible ceramic in many areas of medicine, mainly for contact with bone tissue, due to its resemblance to mineral bone. Owing to the nanofeatures of bone tissue, new nano-HA based materials are among the most promising challenges in bioactive ceramics. Recently, it was observed that fluoroquinolones have the ability to interfere with osteoclastogenesis, in standard polystyrene cell culture plates. The aim of this work is to a...

Eldecalcitol (ED-71; ELD), a 2β-hydroxypropyloxy derivative of 1α,25(OH)2D3, was approved to treat osteoporosis in Japan in 2011. Raloxifene (RAL), a selective estrogen receptor modulator, is available to treat or prevent postmenopausal osteoporosis. In this study, we compared the effects of combining ELD and RAL against each monotherapy in osteoporotic rats.Eight-month-old female Wistar–Imamichi rats were ovariectomi...

Zoledronic acid (AZ), is considered first-line treatment for Paget’s disease (PD) of bone. The most common adverse event is flu-like syndrome, described between 10 and 50% of patients. Nowadays, there is not known exactly the molecular basis of this syndrome yet. Statins play an important role in the mevalonate pathway, blocking the production of proinflammatory cytokines secreted by T cells γ/δ.Objectives: Characterization and in...

Strontium ranelate (SrR) is now widely used for the prevention of osteoporotic fractures. The mechanisms by which this occurs, however, remain unclear. We investigated the actions of Sr2+ salts in bone-forming cultures of primary osteoblasts from rat calvariae. Osteoblasts were treated continuously with either SrR or SrCl2 for 14 days. Abundant, discretely mineralised ‘trabecular’ bone structures formed in alizarin red-stained control cultures. ...

The childhood is an important period for bone mass acquisition, and this tissue may be influenced by the nutritional status. However, the relation between the nutritional status and the bone parameters of quantitative ultrasound (QUS) remains unclear. The aim of this study was to verify the influence of nutritional status on bone mass assessed by QUS in male children from 7 to 10 years old. The sample consisted of 461 Brazilians pre-pubertal schoolchildren (8.30±1.13 year...