Bone Abstracts

Bone strength, hence fracture risk, is dependent on bone geometry, microstructure and bone material level properties. We have reported that microstructure and material level properties contribute independently to the increase in bone strength in rats treated with strontium ranelate for 2 years, as evaluated by μCT-based Finite Element analysis.We investigated the effects of strontium ranelate (SrRan) treatment on bone material level properties of tr...

Introduction: Osteocalcin (OC) is a marker of bone formation but also seems to play a hormonal role in the regulation of glucose and energy metabolism. Recently, an association of BMI with a haplotype composed of three single nucleotide polymorphisms (SNPs) in the gene for OC, located on chromosome 1q22, was observed in ethnically homogeneous European pedigrees.Aim: The aim of the study was to test the association of these three polymorphisms in the gene...

Background: Pseudohypoparathyroidism (PHP) is a group of heterogeneous endocrine disorders characterised by hormone resistance, primarily to parathyroid hormone (PTH). The resistance is caused by defects in the GNAS gene, which encodes the Gsα protein that activates the cAMP pathway. PHP patients demonstrate elevated plasma PTH, hypocalcaemia, hyperphosphataemia with normal renal function. PTH resistance can be confirmed by Ellsworth-Howard test (PTH s...

Introduction: Loss in bone mineral density may occur soon after initiation of adjuvant therapy for hormone-receptor-positive (HR+), breast cancer (BC) and correlates with changes in hormone levels. Adding zoledronic acid (ZOL) to adjuvant treatment for BC can preserve/improve bone mineral density and delay disease recurrence; however, effects of ZOL on endocrine hormone levels are currently unclear.Methods: Probone II assessed the course of endocrine hor...

Objective: To examine the efficacy and safety of direct administration of zoledronate acid (ZOL) on local osteoporotic lesion of ovariectomized rats.Methods: Six weeks later after ovariectomy, 16 6-month-old female S.D. rats were divided into the two groups with no differences of body weight and BMD of the proximal tibia. In the group L, 50 μl ZOL at a dose of 67 μg/kg were locally injected into the bone marrow between the two dr...

Introduction: Collagen and glycosaminoglycans (GAGs) such as hyaluronan (HA) and chondroitin sulfate (CS) are basic elements of bone structure and collagen-GAG composites are currently developed for a wide range of applications. Here, we report on the molecular and cellular effects of GAGs and their sulfated derivatives on osteocytes, which are fundamental orchestrators of bone remodeling.Materials and methods: The effects of native and sulfate-modified ...

Preclinical and epidemiologic data suggest that vitamin D deficiency may play a role in the pathogenesis and progression of prostate cancer. Based on recently reported genetic determinants of vitamin D insufficiency we investigated a functional T>G single nucleotide polymorphism (SNP) in the group-specific component (GC) gene for its association with 25-hydroxy (25-OH) vitamin D and 1.25 dihydroxy (1.25-OH) vitamin D levels and further to test a possible association with m...

The musculoskeletal system experiences severe mechanical strain, with repetitive or extreme strains causing significant trauma; the result being an increase in mechanobiological studies evaluating mechanical strain on musculoskeletal cells. Currently, most stretching studies utilise fibronectin-coated cultures, as these enhance cell attachment. However, recent studies suggest that fibronectin increases cell turnover and DNA damage and affects cell differentiation. Furthermore,...

Acrodysostosis refers to a group of rare chondrodysplasia that share severe brachydactyly, short stature and nasal hypoplasia. Through a candidate gene approach or exome sequencing, heterozygous mutations in PRKAR1A or in PDE4D, respectively, have been identified in patients with acrodysostosis. PRKAR1A encodes the regulatory subunit of the protein kinase A (PKA), which allows, upon binding of cAMP, phosphorylation of target proteins by the catalytic subunit ...

Background: Pseudohypoparathyroidism is characterized by a resistance to parathormone, with variable phenotypical and biochemical manifestations. With genetic disorder caused by heterozygous inactivating mutations in GNAS1, the gene encoding the alpha-chain of G(s), and is associated with short stature, obesity, brachydactyly, and sc ossifications. AHO patients with GNAS1 mutations on maternally inherited alleles also manifest resistance to multiple hormones (e.g. PTH, TSH, LH...