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Osteoclast Recruitment (osteoclast + recruitment)
Selected AbstractsThe effectiveness of polyethylene versus titanium particles in inducing osteolysis in vivo,JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2004Marius von Knoch Abstract Bearing surface wear and periprosthetic osteolysis due to wear particles are among the most common reasons for joint replacement failure. A murine calvarial model of wear particle-induced osteolysis has been used to identify different biologic factors associated with this problem and to test nonsurgical methods of modulating the host response to particulate debris. This model has utilized titanium particles, however, in clinical practice the most common source of particulate debris is polyethylene particles from bearing surface wear. We now report a calvarial model of wear particle-induced osteolysis based on commercially available polyethylene particles. We found that compared to sham surgery osteoclast recruitment and bone resorption can be induced by introduction of the titanium particles or polyethylene particles. However, bone resorption was significantly higher with polyethylene particles compared to titanium particles (p = 0.02). We consider the polyethylene based murine calvarial model of wear particle-induced osteolysis a reliable and clinically relevant tool to understand the host factors and potential pharmacologic interventions that can influence wear debris generated osteolysis. This model might serve as an extension of the well-established titanium based bone resorption model. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Effect of cyclic mechanical loading on osteoclast recruitment in periodontal tissueJOURNAL OF PERIODONTAL RESEARCH, Issue 1 2010K. Nozaki Nozaki K, Kaku M, Yamashita Y, Yamauchi M, Miura H. Effect of cyclic mechanical loading on osteoclast recruitment in periodontal tissue. J Periodont Res 2009; doi: 10.1111/j.1600-0765.2008.01193.x. © 2009 The Authors. Journal compilation © 2009 Blackwell Munksgaard Background and Objective:, It is well accepted that cyclic mechanical loading induces osteoclastogenesis in periodontal tissue, but its molecular mechanisms are not well understood, in part because of a lack of appropriate models. In this study, we investigated a novel device that allows cyclic mechanical loading to be performed in a well-controlled manner. Furthermore, by employing this model, the effect of cyclic loading on osteoclast recruitment in the periodontal tissue was described. Material and Methods:, By using a newly developed device, the cyclic loading of 20 n (reference loading corresponding to the fracture hardness of dietary pellets) and two excessive loadings (i.e. 30 and 40 n) were applied to maxillary right molars in rats for up to 7 d, and osteoclast recruitment in the periodontal tissue was evaluated by analyzing relevant marker proteins using immunohistochemistry. Results:, Osteoclastogenesis was induced by day 3 within alveolar bone subjected to a compression force of 30 n. With both 30 and 40 n loadings, cells that were positive to for tartrate-resistant acid phosphate, receptor activator of nuclear factor-,B ligand and osteoprotegerin were significantly increased in the alveolar bone/periodontal ligament in a time-dependent manner. Conclusion:, A new device was developed that allows various levels of cyclic mechanical loading to be exerted. By using this device in rats, early events of osteoclast recruitment in the periodontal tissues were observed with excessive loadings in a time-dependent manner, indicating the usefulness of this model. [source] Disparate osteogenic response of mandible and iliac crest bone marrow stromal cells to pamidronateORAL DISEASES, Issue 5 2008D Stefanik Objective:, Long-term administration of intravenous bisphosphonates like pamidronate is associated with jaw osteonecrosis but axial and appendicular bones remain unaffected. Pathogenesis of bisphosphonate-associated jaw osteonecrosis may relate to skeletal site-specific effects of bisphosphonates on osteogenic differentiation of bone marrow stromal cells (BMSCs) of orofacial and axial,/,appendicular bones. This study evaluated and compared skeletal site-specific osteogenic response of mandible (orofacial bone) and iliac crest (axial bone) human BMSCs to pamidronate. Materials and methods:, Mandible and iliac crest BMSCs from six normal healthy volunteers were established in culture and tested with pamidronate to evaluate and compare cell survival, osteogenic marker alkaline phosphatase, osteoclast differentiation in co-cultures with CD34+ hematopoietic stem cells, gene expression of receptor activator of NF,B ligand (RANKL) and osteoprotegerin, and in vivo bone regeneration. Results:, Mandible BMSCs were more susceptible to pamidronate than iliac crest BMSCs based on decreased cell survival, lower alkaline phosphatase production, and structurally less organized in vivo bone regeneration. Pamidronate promoted higher RANKL gene expression and osteoclast recruitment by mandible BMSCs. Conclusion:, Mandible and iliac crest BMSC survival and osteogenic differentiation are disparately affected by pamidronate to favor dysregulated mandible bone homeostasis. [source] | ||||||||||