Implant-related infection is one of the most devastating complications in orthopaedic surgery. Many surface and/or material modifications have been developed in order to minimise this problem; however, most of the We describe a method for the study of bacterial adherence in the presence of preosteoblastic cells. For this purpose we mixed different concentrations of bacterial cells from collection and clinical strains of staphylococci isolated from implant-related infections with preosteoblastic cells, and analysed the minimal concentration of bacteria able to colonise the surface of the material with image analysis.Objectives
Methods
Description of an original in vitro protocol for assessing combined bacteria and cell competitive adherence on the surface of biomaterials of medical interest Biomaterial-related infections are a major clinical problem. The pathogenesis of this syndrome has been described as a competitive adherence between bacteria and human cells in the so-called “race for the surface” theory. The aim of this study is to develop an Summary Statement
Objectives
Parathytorid hormone-related protein (107–111) loaded onto biopolymer-coated nanocrystalline hydroxyapatite (HAGlu) improves the bone repair in a cavitary defect in rat tibiae. Biopolymer-coated nanocrystalline hydroxyapatite (HAGlu) made as macroporous foams are promising candidates as scaffolds for bone tissue engineering applications. They exhibit optimal features, promoting internalization, proliferation and differentiation of osteoprogenitors, with an adequate cell colonization over the entire scaffold surface. Parathyroid hormone-related protein (PTHrP) is an important modulator of bone formation. Its 107–111 epitope (osteostatin) exhibits osteogenic properties at least in part by directly acting on osteoblasts. The main aim of this study was to evaluate whether osteostatin loading into HAGlu scaffolds might improve their bone regeneration capacity.Summary Statement
Introduction
Parathyroid hormone-related peptide (PTHrP) has been shown to be an important regulator of bone remodelling1. The aim of this study was to investigate the effect of the N-terminal domain of PTHrP (1–36) on osteogenic and angiogenic gene expression in human osteoblasts (HOB) and human bone marrow stromal cells (hBMSCs). Primary hBMSC's and HOBs were cultured in standard or osteogenic media with different concentrations of PTHrP, either continuously for 8, 24, 48 h and 9 days, or with 3 cycles of intermittent exposure (24 h with PTHrP, 24 h without) over 6 days. Cell lysates were then processed for analysis of gene expression. Expression of the osteogenic markers runt-related transcription factor 2 (RUNX-2), alkaline phosphatase (ALP) and Collagen 1, and the angiogenic marker; vascular endothelial growth factor (VEGF), were measured.Introduction
Materials and Methods