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...

Background: There is still limited information on changes in growth especially segmental growth and bone mass of glucocorticoid(GC) treated boys with Duchenne Muscular Dystrophy (DMD).Objectives: To evaluate changes in growth and bone mass in GC treated boys with DMD.Methods: Retrospective study of 15 boys with DMD treated with GC, median age 7.6 years (4.1, 15.5) who had repeated DXA scan for clinical monitoring of bone health, me...

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...

Objectives: To elucidate the incidence and risk factors of skeletal toxicity in children with ALL treated with the dexamethasone-based DCOG-ALL9 protocol.Methods: Prospectively, the cumulative incidence of fractures was assessed in 672 patients and compared between different subgroups using the log-rank test. Serial measurements of bone mineral density of the lumbar spine (BMDLS) were performed in 399 ALL patients using dual energy X-ray absor...

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...