Bone Abstracts

Objectives: Cross-sectional studies show that exercise may have positive effects on bone outcomes in youth. However, there is no evidence from longitudinal studies, which type of sports can induce improvements in bone acquisition in adolescent athletes. Therefore, this study aimed to investigate the longitudinal differences in bone acquisition and bone metabolism between adolescent males participating in osteogenic (football) and non-osteogenic (swimming, cycling) sports compa...

Osteoclast resorption depends on their ability to reorganise their actin cytoskeleton and form the sealing zone. In order to resorb bone, osteoclasts become polarised by condensing their podosomes into a highly dynamic podosomal belt. The podosome turnover is regulated by several factors such as non-receptor tyrosine kinases, small GTPases and actin-binding proteins. The innate immune system responds to viral pathogens. Cytoplasmic double-stranded DNA activates the immune syst...

Introduction: Liver transplant candidates have bone and mineral metabolism disorders that may influence the development of fractures after liver transplantation (LT).Objective: To analyze the levels of 25-hydroxyvitamin D (25-OH-D) in patient candidates for LT and the factors associated with vitamin D deficiency.Methods: Between January 2010 and May 2012, 116 liver transplant candidates (85 male and 31 female patients) were include...

Introduction: Osteoporosis is a common complication in patients with chronic cholestasis, usually characterized by reduced bone formation. Ursodeoxycholic acid (UDCA) improves differentiation and mineralization and counteracts the damaging effects of bilirubin and lithocholic acid (LCA) in osteoblastic cells. Moreover, UDCA decreases apoptosis in a number of cell lines, but this antiapoptotic effect has not been investigated in bone cells.Aims: To assess...

Wnt–β-catenin signalling and its antagonists (sclerostin and Dkk-1) play an important role in the regulation of bone mass and osteoblastogenesis. Glucocorticoid therapy (GCCT) is a well known factor related to decreased bone formation and osteoporosis development. Therefore, we analyzed the effect of GCCT on Wnt signalling antagonists (sclerostin and Dkk-1) and their relationship to bone mass and bone turnover.Methods: 22 patients (11M/11F, age...

We recently observed an increased risk for vertebral fractures (VF) in a randomized controlled trial comparing the analgesic effect of vertebroplasty (VP) vs conservative treatment (CT) in symptomatic VF. The aim of the present study was to evaluate the risk factors related to the development of VF after VP in these patients.Methods and results: We evaluated risk factors including age, gender, bone mineral density, the number, type and severity of verteb...

Fractures are very common and affect 2% of the population per annum. Fragility fractures represent the greatest unmet need and are associated with high rates of morbidity and mortality. Currently, there is no approved therapy for enhancing healing of fragility fractures. We previously reported that upregulation of the early inflammatory response following skeletal injury can promote fracture repair (Glass et al PNAS 2011). Inflammation represents the earliest response followin...

The aim of this study was to investigate the biocompatibility of hydroxyapatite (HAP) powder from whitemouth croaker fish (Micropogonias furnieri). For this purpose, fragments from HAP with 0.5 cm2 were inserted in the subcutaneous tissue of animals. After 7, 15, and 30 days, histopathological analysis was performed. The results showed that it was possible to detect tissue reactions closely related to cytotoxicity in a time-exposure manner. At day 7, modera...

In this study, the effect of food restriction of 30% in calorie intake on femurs of rats of different ages was investigated. Male Rattus novegicus albinus rats, Holtzman lineage, aged 38 days, 4 and 16 months were used. The animals were divided into six groups (n=8–10 per group), three being control groups (C38, C4 and C16) and three groups on restricted diet (R38, R4 on R16). The restricted animals were submitted to food restriction of 30% being fed wit...

Low bone formation is considered to be the main feature in osteoporosis associated with cholestatic and end-stage liver diseases. Previous studies have demonstrated the deleterious consequences of retained substances such as lithocholic acid (LCA) and bilirubin (Bil) on osteoblastic cells. These effects are neutralized by ursodeoxycholic acid (UDCA). To gain new insights into cholestatic-induced osteoporosis, we have assessed the differential gene expression of osteoblastic ce...