Bone Abstracts

Purpose: The purpose of this study was to investigate the bony change of mandibular condyle when the originally less-loaded or unloaded surface was subjected to functional loading by the newly designed animal experiment, and to evaluate whether this experiment is adequate for the animal model of condylar resorption due to mechanical loading.Methods: Twelve adult male New Zealand white rabbits were used. Unilateral oblique vertical body osteotomy (UOVBO) ...

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...

Background: Osteoporosis is not a homogenous disease. Riggs et al. identified two distinct types of osteoporosis, with different pathophysiology, patterns of bone loss and fracture types.Post-menopausal (PM) osteoporosis is triggered by withdrawal of the effect of oestrogen on bone, which leads to a sharp acceleration of bone turnover with an imbalance towards excessive osteoclastic activity. Senile osteoporosis in the old old (usually after the...

Thalassemia is a chronic anemia associate with high rates of osteoporosis. To determine how erythropoiesis leads to bone loss in thalassemia, we used the th3/+ thalassemia mouse to study the role of erythropoietin (EPO) and hematopoietic progenitors (HP), since they are both increased in thalassemia.Methods: Bone marrow mesenchymal stem cells (MSCs) cultures and MSC cocultures with various HP from wild type (wt) and th3/+ mice were diff...

Growing body of evidence shows that microRNAs play an important role in regulating bone mass. We investigated the cooperative microRNA-mRNA regulatory mechanism of peak bone mass in inbred strain of mice with different bone density using microarray analysis. Femur and tibia of 12-week old C3H/He (high bone density) and C57BL/6 (low bone density) were harvested to extract total bone RNAs for microarray. A total of 30 miRNAs were differentially expressed between bone tissue of C...

Osteogenesis imperfect (OI) is an inheritable bone disease with low bone mass, fragility, deformity and multiple fractures in skeletal tissues. Modulation of Wnt signalling components reportedly alleviates excessive bone and joint remodelling in various skeletal disorders. This study is undertaken to explore whether loss of Wnt inhibitor Dickkopf-1 (Dkk1) action affects bone formation or skeletal homeostasis in OI. In clinical vignettes, OI patients had severe osteoporosis (<e...

Osteoclasts are bone-resorbing multinucleated cells that differentiate from monocyte/macrophage-lineage precursors. Bone destruction and osteoporosis are attributed to excessively activated osteoclasts. Osteoclast differentiation is governed by diverse regulatory processes including nuclear factor-activated T cells c1 (NFATc1) activation in response to RANKL. The mechanism of epigenetic regulation of NFATc1 in osteoclastogenesis not investigated yet. Here we test a hypothesis ...

Ca2+ signaling and NFATc1 activation are essential for RANKL-induced osteoclast differentiation through the induction of Ca2+ oscillation, calcineurin activation, and translocation of NFATc1 into the nucleus. Homer proteins are scaffold proteins that have been proposed to modulate multiple Ca2+ signaling proteins, including inositol 1,4,5-triphosphate receptors, ryanodine receptors, transient receptor potential channels. In this study, we inves...

Introduction: Hypertrophy of ligamentum flavum (LF) induces narrowing of spinal canal which develops neurogenic claudication. Several mechanisms of LF hypertrophy have been suggested. Among them inflammatory cytokine play a crucial role in LF hypertrophy by increasing collagen synthesis. Cyclooxygenase-2 (COX-2) pathway shares inflammatory reaction from infection and arthritis. Selective COX-2 inhibitor (COX-2si) might modulates collagen synthesis via suppressing inflammatory ...

Objective: To analyse the influential factors of lifestyle on vitamin D status among aged people in Shanghai community.Method: Lifestyles of 3846 elderly men and women aged over 65 years were investigated using a self-designed questionnaire from ten communities of urban and suburb in Shanghai China, which contained sociodemographic factors and lifestyle factors and so on. The levels of serum 25(OH)D were measured by Cobas Diagnosis System of Roche. Univa...