Bone Abstracts

Background: Osteogenesis imperfecta (OI) is a hereditary connective tissue disorder characterized by increased bone fragility and low bone mass. The different types of OI may be distinguished by their clinical features and the causative genes, with COL1A1 and COL1A2 genes as the most frequent. The guidelines for OI genetic diagnosis first recommends the screening of COL1A1 and COL1A2 genes using Sanger sequencing. However, this method has li...

Multiple myeloma (MM) bone disease is characterized by lytic bone lesions that contribute to patient morbidity and mortality after patients are in complete remission. The mechanisms mediating this long-term osteoblast (OB) suppression are poorly understood. We hypothesized that MM cells induce epigenetic changes at the Runx2 promoter in preOB bone marrow stromal cells (BMSC). We demonstrated that Gfi1, a transcriptional repressor of Runx2 that is induced in B...

GNAS-Gsalpha based disorders lead to heterogeneous diseases associated with abnormal bone development via two distinct mechanisms. At the level of the growth plate in bones, the PTHrP/PTH1R/Gsalpha/cAMP/PKA/PDE signalling pathway regulates endochondral ossification. PTHrP binds to the PTH receptor (PTH1R) which then couples with the stimulatory G protein (Gsalpha) leading to cAMP formation. cAMP binds to the regulatory 1A subunits (R1A) of the PKA. Upon binding the catalytic s...

Objectives: Vitamin D has an important effect on bone but there are no trials that directly address the boosting of serum levels of 25-hydroxyvitamin D (25OHD) in bone microarchitecture in Juvenile-onset Systemic Lupus patients (JoSLE). The aim of this study was to evaluate the effect of vitamin D supplementation on bone microarchitecture parameters using HR-pQCT in JoSLE patients.Methods: This study was a randomized double-blind placebo-controlled 24-we...

Background: Parathyroid hormone-like hormone (PTHLH) is an important regulator of endochondral bone development. Mutations of the PTHLH gene can cause a variety of different skeletal dysplasias, with duplications of the PTHLH gene resulting in a phenotype characterized by endochrondomatosis, metaphyseal dysplasia and osteolysis.Presenting problem: Our patient presented at the age of 4 months, given concerns regarding lower limb deformit...

Background: Mutations in SATB2 have been described in association with a unique phenotype known as SATB2-associated syndrome (SAS). This condition is characterised by severe intellectual disability affecting speech development, behaviour, facial features and dental anomalies. Skeletal features and osteoporosis have been reported in older individuals (aged 15–36), in association with point mutations. We report a 24-year-old man with a SATB2 misse...

Background: Since Microcephalic osteoplasic dysplasia; Saul Wilson Syndrome (SWS) was first reported by Saul and Wilson in 1990 only 14 cases have been reported worldwide. In 2018 Ferreira et al identified the pathophysiological mechanism for SWS as a recurrent De Novo Heterozygous COG4 Substitution.Objective: To describe the diagnostic process in a case of SWS.Presenting problem: The patient is the first-born child of healthy, non...

Objectives: Osteogenesis Imperfecta (OI), is a group of rare, heritable disorder of bone and connective tissue. The pathogenicity of OI arises from the mutations in about 17 different genes, involved in collagen type 1 synthesis, processing, post-translational modification, folding, cross-linking, bone mineralization, and osteoblast differentiation. Based on Sillence classification, there are four types of OI; Type I (mild, non-deforming), Type II (perinatal lethal), Type III ...

Introduction: Normal mechanical loading potently induces bone formation via effects on osteocytes. Current investigations of mechanical loading of bone do not reflect the interactions of the cells within it, mostly focusing on mechanical loading of osteoblasts in monolayers. Existing 3D models do not elucidate the osteoblast-osteocyte interactions that regulate mechanically-induced bone formation. We developed a novel in vitro 3D co-culture model of bone1 t...

Objectives: Low bone mass in adolescent idiopathic scoliosis (AIS) has been well reported, however the etiologies of the disease and this abnormal phenotype were still unknown. Leptin have profound effects on bone metabolism and skeletal growth, and was speculated to play a role in the etiopathogenesis of AIS. The objective of this study was to investigate the bone quality in AIS and its association with leptin and soluble leptin receptor (sOB-R).Methods...