Bone Abstracts

Objectives: Previous studies have reported that the rise in parathyroid hormone (PTH) concentrations may be used to determine the levels of vitamin D adequacy. However, dietary calcium intake may also influence the rise in PTH. In the light of low calcium intakes in Indian adolescents, our aim was to investigate the relative importance of calcium intake in relationship of serum 25 hydroxyvitamin D (25OHD) with intact serum PTH in apparently healthy children.<p class="abste...

Background: Prader Willi syndrome (PWS) is a genetic disorder characterized by severe hypotonia in infancy, hypogonadism, dysmorphic features, early onset obesity and mild mental retardation.Although hip dysplasia occurs in 10–20% in patients with PWS, hip dislocation requiring surgery is seen rarely. To our knowledge, surgical treatment of hip dislocation in PWS has not been reported before.We present a case with PWS and hip ...

Several cell types form the hematopoietic stem cell niche. These niches sometimes become hijacked by cancer cells, which may later form metastatic lesions. Our aim was therefore to characterize the bone marrow microenvironment to affect cancer cell homing to bone marrow.Pharmacologic modification consisting of PTH to stimulate the osteoblasts and zoledronic acid to prevent the increase in osteoclasts through PTH resulted in increased homing of cancer cel...

Cancer cell growth is dependent on the microenvironmental support. Prostate and mammary cancer (PCa and MCa) cells preferentially metastasize to bone, where they induce either an osteoblastic or osteolytic response. These opposite stromal responses suggest that different types of cancers adopt distinct strategies to hijack the bone marrow/bone stroma for their growth support. However, the molecular cues underlying these divergent responses are largely elusive.<p class="abs...

Intrinsic quality, micro and nano structure of bone after 1 month of spaceflight and during 1 week of recovery had never been investigated. The aim was to explore these properties in appendicular and axial skeleton of mature mice.Ten C57/Bl6 male mice flew on the 30-day space Russian BION-M1 high-orbit satellite mission (Biomedical Ethics Commission of IBMP, n°319). Five were euthanized 12 h after landing, the others 8 days later. A ground control g...

We have previously shown that female neuronal nitric oxide synthase knockout (nNOS KO) mice have increased trabecular bone volume. However, this study was performed in mice at 10 weeks of age only. To investigate whether the high bone volume is maintained during ageing, we compared 3-month- and 12-month-old wild type (WT) and nNOS KO mice using μCT. The tibias from 8 WT and 8 nNOS KO mice at each age were dissected, fixed for 24 h in buffered formalin, stored in 70% ethan...

Context: An increase in bone marrow adiposity (BMA) is usually described in anorexia nervosa (AN) patients and in calorie restriction models. This induced BMA could be involved in the development of the osteoporosis often described in AN. However, BMA increase is not always observed and could be depending on the severity of the deficit.We previously developed the separation-based anorexia mouse model (SBA)1 (Ethical approval CEEA #022012). SBA...

Wnt proteins and their cognate receptors play a significant role in malignant diseases, in particular in prostate cancer (PCa). We previously showed that WNT5A inhibits PCa cell proliferation and induces apoptosis in vitro, leading to reduced PCa growth in vivo. However, the involved receptors remain unknown. Here, we determine the role of two Wnt receptors (FZD8, RYK) and their influence on the WNT5A-induced effects on PCa cells.The ex...

: Osteonecrosis of the jaws (ONJ) is a relatively new adverse effect associated with bisphosphonate therapy, but no causal association has been established. By definition, a patient is considered to suffer from ONJ if he has current or previous treatment with a bisphosphonate, exposed bone in the maxillofacial region that has persisted for more than 8 weeks and no history of radiation therapy to the jaws. It has been proposed that ONJ could be linked with impaired topical immu...

Osteoblasts have a high rate of energy consumption during bone formation and bone protein synthesis. Therefore, it is likely that decreased energy production that accompanies aging, could contribute to reduced osteoblast activity, a critical feature of senile osteoporosis, and that this reduction might be counteracted by favoring energy availability. Cells of the osteoblastic lineage generate 40–80% of the requested energy through fatty acid degradation, thus the modulati...