In cell culture, the cellular responses on Day 6 and Day 18, and matrix mineralization (Day 35) of human periosteal cells after stimulated by ESW, LIPUS and ESW+LIPUS treatments were studied. Our results showed that LIPUS only exerted transiently beneficial effects on Day 6, but no effect was observed on Day 18. In contrast, ESW inhibited the differentiation on Day 6, and then exerted a time-delayed stimulation effect on cellular response and matrix mineralization. Data of the ESW+LIPUS showed that it was mainly under ESW effects, but LIPUS might impact the beneficial effect of ESW on Day 18, leading to reduced ALP and matrix mineralization. The potentials of the osteocytes to function as mechanosensors and signal relay were also investigated with untreated periosteal cells that separately received conditioned medium from MLO-Y4 osteocyte-like cells, which received the ESW LIPUS and ESW+LIPUS treatments. The periosteal cells showed stimulated proliferation in the ESW+LIPUS and ESW groups, indicating that the stimulus of ESW was transferred in the conditioned medium. / In conclusion, although our in vivo and in vitro findings did not support our hypothesis of the beneficial effects of combined treatment, but ESW had been shown to improve BMD and bone microarchitecture in osteoporotic bone, by stimulation of osteogenic activities in osseous cells. ESW might potentially be developed as treatment for osteoporosis. Our study also indicated that stimulation of osteogenic activities may be the direct interaction of ESW on osteoblast/periosteal cells, or indirectly through biochemical signals relayed by the osteocytes which acted as mechanosensors. / Osteoporosis is a bone disorder with decreased bone mass and deteriorated microarchitecture, leading to increased fracture risk. By using non-invasive biophysical interventions that stimulate osteogenesis, i.e. extracorporeal shockwave (ESW) and low-intensity pulsed ultrasound (LIPUS), may reduce bone loss effectively. We hypothesized that the combined treatment of ESW and LIPUS might produce synergistic effects on osteoporotic bone. The aim of this study was to investigate the efficacy of using ESW treatment alone and combined treatment of ESW and LIPUS to increase bone mineral acquisition on intact osteoporotic bone in vivo, and to investigate their underlying mechanisms in vitro. / Ten osteoporotic goats were used and divided into ESW and ESW+LIPUS groups (n=5). The ESW group received shockwave at calcaneus, distal radius, and femoral condyle on the left limbs once per month. The ESW+LIPUS group also received ESW treatment monthly and LIPUS for 6 day/week. The opposite limbs served as contralateral control. After nine months, percentage BMD changes, mineral apposition rate, trabecular thickness in treatment sites were found higher than that of controls in both groups. Cumulatively increase of serum bone-specific alkaline phosphatase indicated that the improvements were due to the increased osteogenic activities in bone. Of all parameter, no significant difference was found between the ESW+LIPUS and ESW groups. / by Tam Kam Fai. / "August 2006." / Adviser: Kwok Sui Leung. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1550. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 156-184). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_343866 |
| Date | January 2006 |
| Contributors | Tam, Kam Fai., Chinese University of Hong Kong Graduate School. Division of Orthopaedics & Traumatology. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xxvi, 194 p. : ill.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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