Bone Abstracts

Background: Noonan syndrome (NS) is a genetic multisystem disorder characterized by distinctive facial features, learning difficulties, short stature, and cardiac defects. Other important findings include skeletal anomalies, especially spinal and chest deformities. Skeletal dysplasia was proven to be secondary to a disorder of RAS-mitogen activated protein kinase (MAPK) pathway which is essential for regulation of cell differentiation and growth including bone homeostasis. We ...

Twelve different mutations in TNFRSF11A (encoding the RANK receptor) have been associated with osteoclast-poor autosomal recessive osteopetrosis in patients. Two truncated RANK proteins resulting from substitution mutations (W434X and G280X), identified in two infants, cause loss of the intracellular oligomerisation motif and in the case of the G280X mutation the TRAF6 binding domain. A third mutation was identified in a 10-year-old patient and is a frameshift mutatio...

Introduction: Atypical markers will provide interesting information in order to assess the bone metabolism. Serotonin has a dual action related to the bone and its serum level is the easiest to use in daily clinical practice also the exact value is not very well described up to this moment.Aim: We correlate to serum levels of serotonin with different results of clinical bone health evaluation in menopausal women.Materials and metho...

Giant cell tumour of bone (GCTb) is an osteolytic neoplasia with tendency to local recurrence (10–25%), while metastases or malignant transformation are described in 1–4% of cases.It is composed by three distinct populations that cross-talk each other generating unbalance in bone remodeling and activation of NF-kB signaling pathway.To identify new candidate biological markers useful for improving clinical management of GC...

In the recent years the role of the skeleton in glucose and energy homeostasis has been studied. In particular the osteoblast-specific protein osteocalcin (OC), in its undercarboxylated form (uOC) has been shown to influence glucose homeostasis in animal models.The aim of our study is to evaluate if the intermittent administration of 1–84 PTH could influence glucose metabolism through its anabolic action on the skeleton.We enr...

Objective: Classical homocystinuria due to cystathionine beta-synthase (CBS) deficiency, is a rare autosomal recessively inherited disease characterized by the multiple involvement on different organs. While the most striking cause of morbidity and mortality is thromboembolism, patients develop a marked osteoporosis at early age along with many other skeletal abnormalities. As CBS normally converts homocysteine to cystathionine, the result of CBS deficiency is an accumulation ...

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Epigenetic mechanisms regulating osteoblast differentiation are still inadequately described. In a genome wide transcriptional profiling of MC3T3-E1 osteoblastic cell line, we identified RCOR2 as a significantly upregulated gene during a differentiation time-course from proliferative to mature osteoblasts. Similar expression profile of RCOR2 was found in mouse calvarial osteoblasts. RCOR2 belongs to CoREST/RCOR family of proteins that regulate action of lysine-specific histone...

Fibrous dysplasia of bone (FD) is a crippling skeletal disease caused by activating mutations (R201C, R201H) of the Gsα gene. We recently generated GsαR201C transgenic mice that develop a FD skeletal phenotype. The analyses of these mice demonstrated that increased bone resorption is one of the main morbidity factors in FD and that RANKL is the major molecular mediator of osteolysis at affected skeletal sites.Ob...

Objective: To characterize a group of children with Osteogenesis Imperfecta (OI) followed up at the University Hospital of Brasília (HUB), Brazil.Methods: Data were collected with children and adolescents that were hospitalized in the HUB for intravenous pamidronate infusion treatment. This hospital is an OI reference center of the Midwest region in Brazil. The sample consisted of thirty-eight subjects, of which 50% were female. 52% of the children ...