Bone Abstracts

Mammalian target of rapamycin (mTOR) functions mainly in the form of two complexes, namely mTORC1 and mTORC2, which are distinct in their unique components, raptor and rictor. Here, we focused on bone phenotypes in mice with a specific deletion of rictor using a Cre recombinase gene whose expression was driven by the promoter of osteocalcin. All procedures involving mice were approved by the Institutional Animal Care and Use Committee of the local admin. DXA analysis showed a ...

Low bone formation is considered to be the main feature in osteoporosis associated with cholestatic and end-stage liver diseases. Previous studies have demonstrated the deleterious consequences of retained substances such as lithocholic acid (LCA) and bilirubin (Bil) on osteoblastic cells. These effects are neutralized by ursodeoxycholic acid (UDCA). To gain new insights into cholestatic-induced osteoporosis, we have assessed the differential gene expression of osteoblastic ce...

I will describe non-cancerous skeletal diseases that occur as a consequence of somatic mutation. I will introduce the work of Drs Mary Lyon, Dorothea Bennett, and Rudolf Happle that provided insights into the mechanism responsible for several genetic, non-heritable diseases. I will then describe the technology and analytic strategies that several laboratories, including my own, employed to identify mutations in patients with Maffucci, Proteus, CLOVES, and Klippel-Trenaunay syn...

Nitrogen-containing bisphosphonates (N-BPs) are used to treat osteolytic bone metastases. N-BPs have been previously shown to enter macrophages via macropinocytosis, but the mechanisms how they are taken up by breast cancer cells are so far incompletely known. In breast cancer primary tumours N-BPs have been shown, by other researchers, to be bound to micro-calcifications present in the tumour stroma. In our study we have characterized how different N-BP formulations, free, ca...

Objectives: This study thus was aimed at investigating of ultrastructure of the hipbone biomineral in rats with defect in tibia after 60-day per os administration of sodium benzoate (SB) in various concentrations and mexidol (M).Methods: The experiment involved 280 male thoroughbred rats with initial body weight of 200–210 g. The 1st group (K) comprised animals that received daily per os 1 ml of 0.9% solution of NaCl, the 2nd and t...

Objectives and method: We retrospectively reviewed records of current patients with osteogenesis imperfecta (OI) to identify those on risedronate, doses used and effects of treatment. BMD changes over time were calculated as difference between measurement before risedronate and at one year (including measurements −3–0 m and 10–14 m after starting risedronate respectively).Results: 219/296 (74%) patients with OI had received bisphosphonate...

Introduction: Treatment in thyroid function disorders, which lead to clinical hypothyroidism, is replacement with levothyroxine. We aimed to investigate the effect of long-term levothyroxine therapy on vitamin D metabolism and bone mineral density in children.Materials and methods: Twenty-seven children with hypothyroidism receiving levothyroxine therapy (M/F: 13/14, mean age, 12.1±0.7 years) and 21 healthy controls (M/F: 13/8, mean age, 11.8±0...

Aims: To review changes in the advice regarding vitamin D deficiency in the UK and compare these with other national guidance.Methods: All Vitamin D guidance in the Royal College of Paediatrics and Child Health 2003 guide (Medicines for Children) and in the eight editions since the British National Formulary for Children (BNFc) was first published in 2005 was reviewed.Results: Dosage and indications of prevalence are shown in the T...

Extracellular nucleotides, signalling through P2 receptors, play a significant role in bone biology. ATP and ADP act via the P2Y1 or P2Y12 receptors to promote osteoclast formation and activity. Bone cells express the P2Y2 receptor and, in osteoblasts, it plays a role in regulating bone mineralisation. This investigation examined the role of the P2Y2 receptor in osteoclasts. Primary osteoclasts were isolated from the bone ma...

High resolution peripheral quantitative computed tomography (HR-pQCT) in combination with micro finite element analysis (μFEA) is a promising tool to assess longitudinal changes in bone mechanical properties during the fracture healing process in the distal radius. In the present study we investigate if these changes can be detected as well when using images with lower resolutions, comparable to clinical QCT images.Postmenopausal women with a stable...