Kanczler J.M.,Bone and Joint Research Group |
Ginty P.J.,University of Nottingham |
White L.,University of Nottingham |
Clarke N.M.P.,University of Southampton |
And 3 more authors.
Biomaterials | Year: 2010
Regenerating bone tissue involves complex, temporal and coordinated signal cascades of which bone morphogenic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF165) play a prominent role. The aim of this study was to determine if the delivery of human bone marrow stromal cells (HBMSC) seeded onto VEGF165/BMP-2 releasing composite scaffolds could enhance the bone regenerative capability in a critical sized femur defect. Alginate-VEGF165/PDLLA-BMP-2 scaffolds were fabricated using a supercritical CO2 mixing technique and an alginate entrapment protocol. Increased release of VEGF165 (750.4 ± 596.8 ρg/ml) compared to BMP-2 (136.9 ± 123.4 ρg/ml) was observed after 7-days in culture. Thereafter, up till 28 days, an increased rate of release of BMP-2 compared to VEGF165 was observed. The alginate-VEGF165/PDLLA-BMP-2 + HBMSC group showed a significant increase in the quantity of regenerated bone compared to the alginate-VEGF165/PDLLA-BMP-2 and alginate/PDLLA groups respectively in a critical sized femur defect study as indices measured by μCT. Histological examination confirmed significant new endochondral bone matrix in the HBMSC seeded alginate-VEGF165/PDLLA-BMP-2 defect group in comparison to the other groups. These studies demonstrate the ability to deliver a combination of HBMSC with angiogenic and osteogenic factors released from biodegradable scaffold composites enhances the repair and regeneration of critical sized bone defects. © 2009 Elsevier Ltd. All rights reserved.
PubMed | University of Auckland and Bone and Joint Research Group
Type: Journal Article | Journal: Rheumatology (Oxford, England) | Year: 2016
Imaging and pathology studies have established a close relationship between tophus and bone erosion in gout. The tophus is an organized structure consisting of urate crystals and chronic inflammatory tissue. The aim of this work was to examine the relationship between bone erosion and each component of the tophus.Plain radiographs and dual energy CT scans of the feet were prospectively obtained from 92 people with tophaceous gout. The 10 MTP joints were scored for erosion score, tophus urate and soft tissue volume. Data were analysed using generalized estimating equations and mediation analysis.Tophus was visualized in 80.2% of all joints with radiographic (XR) erosion [odds ratio (OR) = 7.1 (95% CI: 4.8, 10.6)] and urate was visualized in 78.6% of all joints with XR erosion [OR = 6.6 (95% CI: 4.7, 9.3)]. In mediation analysis, tophus urate volume and soft tissue volume were directly associated with XR erosion score. About a third of the association of the tophus urate volume with XR erosion score was indirectly mediated through the strong association between tophus urate volume and tophus soft tissue volume.Urate and soft tissue components of the tophus are strongly and independently associated with bone erosion in gout.