Bone Abstracts

Mutations in LRP5 cause a variety of phenotypes, including high bone mass and low bone mass disorders. In patients with high bone mass, different heterozygous mutations have been described, all of them clustering in a region including the binding pocket for DKK1 and sclerostin. The pathogenic mechanism is thought to be a gain-of-function mediated by an impaired inhibition of the canonical Wnt signalling pathway, thereby leading to increased bone modelling.<p class="abstext...

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An increasing number of biomaterials are in development, seeking to mimic the natural cascade of events during fracture repair. However, these biomaterials need to be rigorously tested prior to clinical application. In vitro testing lacks the physiological environment, while in vivo studies do not always predict the patient response. Here we hypothesize that the chorioallantoic membrane (CAM) assay can be used to culture human living bone and we aim to examin...

Background: Hypophosphatasia is generally regarded as a disease of bone and teeth. Lack of Tissue Non-Specific Alkaline Phosphatase (TNAP) leads to an accumulation of inorganic pyrophosphate and the Vitamin B6 metabolite pyridoxal 5′-phosphate (PLP), a reduction in pyridoxic acid (PA) and increased PLP/PA ratio. Vitamin B6 deficiency in the brain impairs synthesis of neurotransmitters, and is a well-recognised cause of neonatal seizures. We have found no previous reports...

Bone fractures may depend on Vitamin D Receptor Gene (VDR), bone mineral density, bone turnover markers.Patients and methods: About 161 patients were recruited and underwent: skeletal densitometry (DXA) method and bone turnover studies (Osteocalcin and Ntx).The study group was evaluated using restriction enzyme digestion at BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232) and TaqI (rs731236), polymorphic sites of t...

Aims: To investigate the role of interleukin-6 (IL-6) as a modulator of osteoclastic resorption in vitro in acute Charcot osteoarthropathy.Material and methods: Peripheral blood mononuclear cells were isolated from six patients with acute Charcot osteoarthropathy, five diabetic and five healthy controls and cultured in vitro on bovine bone disks for 21 days in the presence of i) macrophage-colony stimulating factor (M-CSF) and receptor ...

FDA guidelines recommend the sheep as large animal model for osteoporosis. Studies of osteoporosis induction use dual energy x-ray absorptiometry (DEXA) to evaluate bone status. Experimentally, the T-score is calculated based on reference bone mineral density (BMD) values of animals before treatment (0 M). Whereas clinically the reference BMD represents values of an independent group of patients around 30 years old. The study hypothesize that the use of additional ind...

In rural Gambian prepubertal children with low calcium intakes (mean 300 mg/day) we reported positive effects, sustained for at least a year (y), on bone mineral content (BMC) after 12 months supplementation with calcium carbonate to international levels1,2. The group was followed up regularly until the end of height growth, and supplementation did not affect height growth in the girls3. Our aim was to determine whether the supplementation altered the tim...

Purpose: The aim of our study is a micro-CT-based, longitudinal characterisation of ovariectomy, multideficient diet and corticoid therapy impact on the ossal microarchitecture.Materials and methods: Four randomized groups were formed out of 32 adult female merino land sheep:1. control2. ovariectomized (OVX)3. OVX+multideficient diet (OVX-D)4. OVX-D+320 mg methylp...

Biographical DetailsDr Marie Gdalevitch completed both her medical and orthopedic surgery degrees at McGill University. Following her residency, Dr M Gdalevitch pursued her first fellowship in limb lengthening and deformity correction at the International Center for Limb Lengthening in Baltimore, Maryland. Dr M Gdalevitch then embarked on her second fellowship in pediatric orthopedics and...