Bone Abstracts

Objectives: Bisphosphonate infusions are associated with numerous adverse effects including acute systemic inflammatory reactions and electrolyte abnormalities. The aims of this study were to evaluate the safety and efficacy of a 3-day course of prednisone on children receiving their first dose of pamidronate or zoledronic acid.Methods: A retrospective cohort of 166 patients (85 males) were commenced on pamidronate (16%) or zoledronic acid (84%) for trea...

Childhood hypothyroidism results in delayed skeletal maturation and impaired growth. Thyroid hormones act via temporo-spatially regulated thyroid hormone receptors α (TRα) and (TRβ).In the skeleton, TRα is the predominant receptor and we hypothesise that the skeletal effects of hypothyroidism are mediated by TRα.To investigate this we assessed the response of wild-type (WT), TRα knockout (TRα...

Thyrotoxicosis results in osteoporosis, and thyroid hormone (T3) stimulates osteoclastic bone resorption by unknown mechanisms. We previously demonstrated that knockout mice lacking thyroid hormone receptor α (TRα0/0) are euthyroid but have high bone mass, whereas mice lacking TRβ (TRβ−/−) are thyrotoxic and osteoporotic. Tartrate resistant acid phosphatase (TRAcP) staining revealed osteoclast numbers were reduced by 13% (<...

Introduction: Benign osteopetrosis type 2 (OPTA2) (Albers-Schönberg disease) is usually associated with a heterozygous mutation in CLCN7. Patients may be asymptomatic and present following an x-ray taken for other reasons or with a low trauma fracture. There may be a family history. Homozygous mutations in CLCN7 usually result in severe disease which presents in the neonatal period or early infancy. We present a case of benign osteopetrosis associated wi...

Objectives: Childhood osteoporosis can be treated with i.v. bisphosphonates in order to improve bone mass and density. The aims of this study were to evaluate the safety and efficacy of 6-monthly zoledronic acid (ZA) in children with osteoporosis.Methods: A retrospective cohort study of 27 patients (16 males and 11 females) were treated with 6-monthly ZA (0.05 mg/kg per dose) for a minimum of 1 year. Seventeen patients were immobile, 4 had steroid-induce...

Introduction: Bisphosphonate treatment in children with osteogenesis imperfecta reduces bone catabolism and relies on modelling to form new bone. An anabolic treatment, anti-sclerostin antibody (Anti-SOST Ab), is being investigated in clinical trials. We hypothesized that combined treatment may produce superior outcomes in OI.Methods: Female Col1a2 G610C mice and their wild type littermates (WT) were treated from week 5 to week 9 of life with either sali...

Fibrous dysplasia (FD) is a benign skeletal disease caused by somatic activating mutations of Gsα leading to formation of expansile fibroosseous lesions. These may occur in isolation or in association with McCune-Albright syndrome (MAS), characterized by skin pigmentation and hyperfunctioning endocrinopathies, including growth hormone (GH) excess. FD in the craniofacial skeleton may result in significant morbidity including facial asymmetry, vision and hearing ...

It is well established that tumor expression of Gli2, a Hedgehog family transcription factor, contributes to tumor-induced bone disease. Our previous studies investigating genetic inhibition of Gli2 expression in tumor cells have shown promise for the development of therapeutics. While many groups have focused on developing upstream Hedgehog inhibitors for soft-tissue tumors that aberrantly express Gli proteins, we have previously demonstrated that the expression of Gli2 in tu...

Objectives: While local gene therapy for bone applications has shown some success in preclinical models, systemic delivery of transgenes to the skeleton remains a considerable challenge. Viral vectors such as adeno-associated viruses (AAVs) have great potential as vectors for systemic transgene delivery and may be adapted for emerging gene editing technologies. Furthermore, AAV vectors can have high efficiency, low immunogenicity, and selective tropism towards different tissue...

Objectives: Nutritional rickets results from the interaction of poor vitamin D status and limited calcium intake. Elevated serum alkaline phosphatase is a marker of impaired mineralization in many forms of rickets. We assessed the reliability of serum alkaline phosphatase in identifying nutritional rickets in calcium-deprived Nigerian children.Methods: We reanalyzed data from a case-control study of Nigerian children with active rickets (cases) and age-,...