Bone Abstracts

see P194....

Background: Vitamin D plays an important role in calcium and phosphate homeostasis. Circulating 25 hydroxyvitamin D [25(OH)D] is metabolised into its biologically active form 1,25-dihydroxyvitamin D [1,25-d(OH)D] by the actions of 1α hydroxylase, and into inactive 2metabolite 24,25-dihydroxyvitamin D [24,25-d(OH)D] by 24-hydroxylase. Recent studies suggest the production of 1,25-d(OH)D) from 25(OH)D is 24,25-d(OH)D dependent. Genetic mutations of CYP24A1 gene resulting in...

Neuropeptide Y Y1 receptor (Y1R) signalling has been shown to play a key role in bone homeostasis, emerging as a novel therapeutic target in bone diseases. Y1R knockout mice (Y1−/−) display a high-bone mass phenotype that has been mainly attributed to increased osteoblast activity. Nevertheless, the Y1R regulatory role on osteoclastogenesis and matrix resorption remains largely unknown. To clarify th...

Purpose: Research suggests that dancers are at higher risk of developing low bone mineral density (BMD) compared with the general population. However, the associated factors contributing to low BMD in dancers are not fully understood. We aimed to assess the association of single-nucleotide polymorphisms (SNPs) in the Wnt/β-catenin and oestrogen receptor (ER) signalling pathways with low BMD in dancers.Methods: A genetic association study was conduct...

Objectives: Asfotase alfa (AA), an enzyme replacement therapy, is the only approved treatment for pediatric-onset hypophosphatasia (HPP). We evaluated the safety profile of AA from the clinical trial program spanning pediatric and adult patients.Methods: Safety data were pooled from 4 open-label, multicenter studies in children aged ≤3 years (study 002/003 [NCT00744042/NCT01205152]; n=11) and ≤5 years (study 010-10 [NCT01176266]; <em...

Objectives: To describe the incidence of vertebral fractures in steroid-treated children.Methods: Fractures were assessed prospectively each year for 3 years according to the Genant semi-quantitative method. Proportions of children with incident fractures were determined annually over the study period. To examine associations with baseline clinical factors, the 3-year total number of incident fractures was analyzed using multivariable Poisson regression....

Objectives: Low bone mass in adolescent idiopathic scoliosis (AIS) has been well reported, however the etiologies of the disease and this abnormal phenotype were still unknown. Leptin have profound effects on bone metabolism and skeletal growth, and was speculated to play a role in the etiopathogenesis of AIS. The objective of this study was to investigate the bone quality in AIS and its association with leptin and soluble leptin receptor (sOB-R).Methods...

Objectives: High resolution peripheral quantitative computed tomography (HR-pQCT) was used to evaluate bone quality and volumetric bone mineral density (vBMD). However, manufacturers only provide a standard protocol for adult but not for growing subjects. The aim of this study was to investigate the difference on measurement between two different HR-pQCT scanning protocols in adolescence with unfused growth plate.Methods: 27 boys and 26 girls aged 13&#15...

Introduction: We recently showed that patients with primary Sjögren Syndrome (pSS) have significantly higher bone mineral density (BMD) in the lumbar spine and femoral neck compared with healthy controls. The majority of those patients (69%) were using hydroxychloroquine (HCQ), which may have favourable effects on BMD.Aim: To evaluate whether HCQ modulates human bone cells in vitro.Methods: Osteoblasts were differenti...

Objective: Previous study in Hong Kong reported boy-to-girl ratio of limb fracture was 5.5:1 in the adolescent group. Chinese children have increased risk for forearm fracture during puberty. This study aimed to investigate cortical growth in healthy Chinese adolescents during pubertal growth.Methods: 214 boys and 219 girls aged between 7 and 17 years old with no bone diseases were recruited. Maturity was assessed by self-reported Tanner staging. Images ...