Bone Abstracts

Objectives: From late 2015 a new protocol for zoledronic acid was adopted in our centre. This led to many children changing from pamidronate (PAM) to zoledronic acid (ZA) treatment. In a minority of cases the children and/or their families felt strongly that they wanted to change back to PAM. We present the characteristics of that minority and how bone turnover markers (BTMs) and bone mineral densities (BMD) changed whilst on ZA.Method: From Nov 2016 to ...

The effects of prolactin on bone metabolism have been the subjects of several studies. It is believed that prolactin acts directly influencing the synthesis of bone matrix by stimulating the osteoblastic activity, since receptors for this hormone have been identified in osteoblasts and human mesenchymal stem cells (MSCs). However, no study on the effects of prolactin on the osteogenic differentiation of MSCs was found in the literature. The objective of this study was to verif...

The lactation has been considered a cause of bone loss in humans and animals. Studies have shown that during lactation, there is a significant reduction of bone mineral density. Rats at the end of lactation show reduced bone mass. The objective of this study was to verify the effect of lactation under osteogenic potential of bone marrow mesenchymal stem cells (BMMSCs) of female rats. Twelve Wistar rats were distributed among the control and lactating groups. The experiment was...

The exposition of shift workers to light at night supresses the melatonin (ME) production. ME supression may contribute to the development of osteoporosis, which can be prevented and treated by resistance exercise (RE). This study evaluated the effect of ME release supression by pineal gland (pinealectomy) and the RE on rats tibiae morphology, mineral quantification and mechanical parameters. The project was approved by the local ethics committee (protocol 2014-00939). Fourty ...

Objective: Evidence for further reduction of nonvertebral fracture (NVFX) beyond 3 years of antiresorptive therapy is limited. Since long-term denosumab (DMAb) treatment is associated with continuous increases in BMD and sustained fracture reduction, we analyzed the influence of femoral neck (FN) BMD after 3 years on NVFX rates.Methods: Long-term subjects received 7 continuous years of DMAb; cross-over subjects received 3 years of placebo (FREEDOM) and 4...

Background: Hypercalcaemia is a risk following stem cell transplant (SCT) for all types of autosomal recessive osteopetrosis (ARO) due to restored osteoclast differentiation. This can be particularly severe in the osteoclast-poor (OP) form involving the tumour necrosis factor receptor superfamily 11A (TNFRSF11A) gene, encoding RANK. Denosumab, a monoclonal antibody blocking RANK activation, has been described for refractory post-SCT hypercalcaemia in two cases. Our case adds n...

Osteoclast presents a central role in several inflammatory diseases that are associated to bone destruction. This condition results from increased osteoclastic bone resorption and/or decreased bone formation. Fluoride (F) is widely consumed in the drinking water due to its anticariogenic effect and has been shown to modulate in vivo bone metabolism in a strain-specific dependent manner. It enhances bone formation in 129P3/J mice but not in A/J mice. However, its effec...

DMAb increases BMD and reduces bone resorption and risk of vertebral, nonvertebral and hip fractures in women with PMO. Transiliac crest bone biopsies in 47 subjects treated with DMAb for 1–3 years showed reduced bone turnover vs 45 Pbo-treated subjects, which reversed on treatment cessation. Since bone turnover reduction is sustained and fracture incidence low over 6 years’ DMAb treatment, we evaluated DMAb’s effects on tissue-level remodelling in the FREEDOM E...

Changes in the ability of self-renewal and differentiation of mesenchymal stem cells may be affected by osteoporosis. The aim of this investigation was to compare the transcriptional profile of mRNAs and miRNAs of osteoblastic cells from calvaria and bone marrow of female rats after ovariectomy. Following the approval by ethics committee, 18 wistar rats were divided into control (sham) and ovariectomized groups. After 150 days, both groups were sacrificed to collect the femurs...

Objective: Idiopathic hypercalciuria (IH) is defined as excessive 24 h urinary calcium excretion (>4 mg/kg per 24 h), that persists after correction of dietary imbalances in the absence of secondary causes. Recent studies with DXA in children with IH provide evidence of decreased areal BMD. We used peripheral quantitative computed tomography (pQCT) of the tibia, to test the hypothesis that IH results in decreases of volumetric (mg/cm3) BMD of the trabecular and/...