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Sangwook Tim Yoon - One of the best experts on this subject based on the ideXlab platform.
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Upregulation of intervertebral disc-cell Matrix Synthesis by pulsed electromagnetic field is mediated by bone morphogenetic proteins.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, William C. Hutton, Sangwook Tim YoonAbstract:STUDY DESIGN An in vitro study on the effects of pulsed electromagnetic field (PEMF) on intervertebral disc-cell Matrix Synthesis. OBJECTIVES The objective of the study was to determine whether (1) PEMF can upregulate intervertebral disc-cell Matrix Synthesis and (2) any upregulation obtained is through transforming growth factor (TGF)-β or bone morphogenetic proteins (BMPs). SUMMARY OF BACKGROUND DATA PEMF has been reported to produce cell proliferation, enhance cell function, and upregulate Matrix Synthesis in cell types such as osteoblasts, chondroblasts, endothelial cells, and fibroblasts through the upregulation of several growth factors. PEMF has been used clinically in the treatment of delayed bone union. However, PEMF has never been tested on human intervertebral disc cells. METHODS The PEMF signal used was similar to that used in the clinical treatment of delayed fracture healing. Human disc cells were treated with PEMF for 8 hours per day for 3 days. Quantitative real-time polymerase chain reaction was performed to determine mRNA expression levels of aggrecan, collagen-2, TGF-β, BMP-2, and BMP-7. Sulfated glycosaminoglycan Synthesis was analyzed using the dimethylmethylene blue (DMMB) method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. To determine whether any action of PEMF was through BMP, recombinant human Noggin was used at a dose of 100 ng/mL to block BMP. RESULTS PEMF could upregulate intervertebral disc-cell Matrix Synthesis. BMP-7 was markedly upregulated by PEMF and was upregulated much more than BMP-2. TGF-β was not upregulated by PEMF. The effect of PEMF on disc-cell Matrix was entirely inhibited in the presence of Noggin. CONCLUSIONS PEMF acts through BMPs to upregulate intervertebral disc-cell Matrix Synthesis.
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Pulsed Electromagnetic Field (PEMF) plus BMP-2 upregulates intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, Sangwook Tim Yoon, William C. HuttonAbstract:Study design An in vitro study using human intervertebral disc (IVD) cells. Objectives To determine if pulsed electromagnetic field (PEMF) plus bone morphogenetic protein (BMP)-2 could upregulate IVD-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone. Summary of background data BMP-7 and BMP-2 can both upregulate IVD-cell Matrix Synthesis. There are problems associated with using either BMP-2 or BMP-7. They can diffuse away rather quickly after injection into the IVD space, they cost a lot, and they have side effects such as soft-tissue inflammation and swelling. PEMF has been reported to stimulate various types of cells. PEMF is safe, inexpensive, and noninvasive, thus multiple use is possible. However, PEMF alone has a rather weak effect on disc cells. We decided to carry out an experiment whereby we combined PEMF with BMP-2. Our thoughts were that BMP-2 plus PEMF could be better than either alone. Methods The PEMF signal used was similar to that used in the clinical treatment of fracture nonunions or delayed fracture healing. Human disc cells were treated with BMP-2 alone or PEMF alone or PEMF plus BMP-2. Quantitative real-time PCR was performed to determine mRNA expression levels of aggrecan, collagen-2, transforming growth factor (TGF)-β, BMP-2, and BMP-7. Sulfated glycosaminoglycanSynthesis was analyzed using the dimethylmethylene blue method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. Results PEMF plus BMP-2 upregulates IVD-cell Matrix Synthesis more than BMP-2 alone or PEMF alone, and the effect seems to be synergistic. Also, PEMF plus BMP-2 induces more endogenous BMP-7 and BMP-2 mRNA levels as well as protein levels, as compared with either PEMF alone or BMP-2 alone. Conclusions PEMF plus BMP-2 acts in synergy to upregulate intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
William C. Hutton - One of the best experts on this subject based on the ideXlab platform.
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Upregulation of intervertebral disc-cell Matrix Synthesis by pulsed electromagnetic field is mediated by bone morphogenetic proteins.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, William C. Hutton, Sangwook Tim YoonAbstract:STUDY DESIGN An in vitro study on the effects of pulsed electromagnetic field (PEMF) on intervertebral disc-cell Matrix Synthesis. OBJECTIVES The objective of the study was to determine whether (1) PEMF can upregulate intervertebral disc-cell Matrix Synthesis and (2) any upregulation obtained is through transforming growth factor (TGF)-β or bone morphogenetic proteins (BMPs). SUMMARY OF BACKGROUND DATA PEMF has been reported to produce cell proliferation, enhance cell function, and upregulate Matrix Synthesis in cell types such as osteoblasts, chondroblasts, endothelial cells, and fibroblasts through the upregulation of several growth factors. PEMF has been used clinically in the treatment of delayed bone union. However, PEMF has never been tested on human intervertebral disc cells. METHODS The PEMF signal used was similar to that used in the clinical treatment of delayed fracture healing. Human disc cells were treated with PEMF for 8 hours per day for 3 days. Quantitative real-time polymerase chain reaction was performed to determine mRNA expression levels of aggrecan, collagen-2, TGF-β, BMP-2, and BMP-7. Sulfated glycosaminoglycan Synthesis was analyzed using the dimethylmethylene blue (DMMB) method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. To determine whether any action of PEMF was through BMP, recombinant human Noggin was used at a dose of 100 ng/mL to block BMP. RESULTS PEMF could upregulate intervertebral disc-cell Matrix Synthesis. BMP-7 was markedly upregulated by PEMF and was upregulated much more than BMP-2. TGF-β was not upregulated by PEMF. The effect of PEMF on disc-cell Matrix was entirely inhibited in the presence of Noggin. CONCLUSIONS PEMF acts through BMPs to upregulate intervertebral disc-cell Matrix Synthesis.
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Pulsed Electromagnetic Field (PEMF) plus BMP-2 upregulates intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, Sangwook Tim Yoon, William C. HuttonAbstract:Study design An in vitro study using human intervertebral disc (IVD) cells. Objectives To determine if pulsed electromagnetic field (PEMF) plus bone morphogenetic protein (BMP)-2 could upregulate IVD-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone. Summary of background data BMP-7 and BMP-2 can both upregulate IVD-cell Matrix Synthesis. There are problems associated with using either BMP-2 or BMP-7. They can diffuse away rather quickly after injection into the IVD space, they cost a lot, and they have side effects such as soft-tissue inflammation and swelling. PEMF has been reported to stimulate various types of cells. PEMF is safe, inexpensive, and noninvasive, thus multiple use is possible. However, PEMF alone has a rather weak effect on disc cells. We decided to carry out an experiment whereby we combined PEMF with BMP-2. Our thoughts were that BMP-2 plus PEMF could be better than either alone. Methods The PEMF signal used was similar to that used in the clinical treatment of fracture nonunions or delayed fracture healing. Human disc cells were treated with BMP-2 alone or PEMF alone or PEMF plus BMP-2. Quantitative real-time PCR was performed to determine mRNA expression levels of aggrecan, collagen-2, transforming growth factor (TGF)-β, BMP-2, and BMP-7. Sulfated glycosaminoglycanSynthesis was analyzed using the dimethylmethylene blue method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. Results PEMF plus BMP-2 upregulates IVD-cell Matrix Synthesis more than BMP-2 alone or PEMF alone, and the effect seems to be synergistic. Also, PEMF plus BMP-2 induces more endogenous BMP-7 and BMP-2 mRNA levels as well as protein levels, as compared with either PEMF alone or BMP-2 alone. Conclusions PEMF plus BMP-2 acts in synergy to upregulate intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
Motohiro Okada - One of the best experts on this subject based on the ideXlab platform.
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Upregulation of intervertebral disc-cell Matrix Synthesis by pulsed electromagnetic field is mediated by bone morphogenetic proteins.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, William C. Hutton, Sangwook Tim YoonAbstract:STUDY DESIGN An in vitro study on the effects of pulsed electromagnetic field (PEMF) on intervertebral disc-cell Matrix Synthesis. OBJECTIVES The objective of the study was to determine whether (1) PEMF can upregulate intervertebral disc-cell Matrix Synthesis and (2) any upregulation obtained is through transforming growth factor (TGF)-β or bone morphogenetic proteins (BMPs). SUMMARY OF BACKGROUND DATA PEMF has been reported to produce cell proliferation, enhance cell function, and upregulate Matrix Synthesis in cell types such as osteoblasts, chondroblasts, endothelial cells, and fibroblasts through the upregulation of several growth factors. PEMF has been used clinically in the treatment of delayed bone union. However, PEMF has never been tested on human intervertebral disc cells. METHODS The PEMF signal used was similar to that used in the clinical treatment of delayed fracture healing. Human disc cells were treated with PEMF for 8 hours per day for 3 days. Quantitative real-time polymerase chain reaction was performed to determine mRNA expression levels of aggrecan, collagen-2, TGF-β, BMP-2, and BMP-7. Sulfated glycosaminoglycan Synthesis was analyzed using the dimethylmethylene blue (DMMB) method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. To determine whether any action of PEMF was through BMP, recombinant human Noggin was used at a dose of 100 ng/mL to block BMP. RESULTS PEMF could upregulate intervertebral disc-cell Matrix Synthesis. BMP-7 was markedly upregulated by PEMF and was upregulated much more than BMP-2. TGF-β was not upregulated by PEMF. The effect of PEMF on disc-cell Matrix was entirely inhibited in the presence of Noggin. CONCLUSIONS PEMF acts through BMPs to upregulate intervertebral disc-cell Matrix Synthesis.
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Pulsed Electromagnetic Field (PEMF) plus BMP-2 upregulates intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
Journal of spinal disorders & techniques, 2013Co-Authors: Motohiro Okada, Jinhwan Kim, Sangwook Tim Yoon, William C. HuttonAbstract:Study design An in vitro study using human intervertebral disc (IVD) cells. Objectives To determine if pulsed electromagnetic field (PEMF) plus bone morphogenetic protein (BMP)-2 could upregulate IVD-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone. Summary of background data BMP-7 and BMP-2 can both upregulate IVD-cell Matrix Synthesis. There are problems associated with using either BMP-2 or BMP-7. They can diffuse away rather quickly after injection into the IVD space, they cost a lot, and they have side effects such as soft-tissue inflammation and swelling. PEMF has been reported to stimulate various types of cells. PEMF is safe, inexpensive, and noninvasive, thus multiple use is possible. However, PEMF alone has a rather weak effect on disc cells. We decided to carry out an experiment whereby we combined PEMF with BMP-2. Our thoughts were that BMP-2 plus PEMF could be better than either alone. Methods The PEMF signal used was similar to that used in the clinical treatment of fracture nonunions or delayed fracture healing. Human disc cells were treated with BMP-2 alone or PEMF alone or PEMF plus BMP-2. Quantitative real-time PCR was performed to determine mRNA expression levels of aggrecan, collagen-2, transforming growth factor (TGF)-β, BMP-2, and BMP-7. Sulfated glycosaminoglycanSynthesis was analyzed using the dimethylmethylene blue method. Western blot analysis was performed to determine the protein levels of TGF-β, BMP-2, and BMP-7. Results PEMF plus BMP-2 upregulates IVD-cell Matrix Synthesis more than BMP-2 alone or PEMF alone, and the effect seems to be synergistic. Also, PEMF plus BMP-2 induces more endogenous BMP-7 and BMP-2 mRNA levels as well as protein levels, as compared with either PEMF alone or BMP-2 alone. Conclusions PEMF plus BMP-2 acts in synergy to upregulate intervertebral disc-cell Matrix Synthesis more than either BMP-2 alone or PEMF alone.
Max G. Bachem - One of the best experts on this subject based on the ideXlab platform.
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Identification of mediators stimulating proliferation and Matrix Synthesis of rat pancreatic stellate cells
American Journal of Physiology-Cell Physiology, 2001Co-Authors: Eric Schneider, Alexandra Schmid-kotsas, Jinshun Zhao, Hans Weidenbach, Roland M. Schmid, Andre Menke, Guido Adler, Johannes Waltenberger, Adolf Grünert, Max G. BachemAbstract:The aim of this study was to identify fibrogenic mediators stimulating activation, proliferation, and/or Matrix Synthesis of rat pancreatic stellate cells (PSC). PSC were isolated from the pancreas...
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α2-Macroglobulin reduces paracrine- and autocrine-stimulated Matrix Synthesis of cultured rat hepatic stellate cells
European journal of clinical investigation, 1999Co-Authors: G. G. Schüftan, Max G. BachemAbstract:BACKGROUND Transforming growth factor beta1 (TGF-beta1) is considered to represent a major fibrogenic mediator in the liver. The aim of the present study was to investigate whether alpha2-macroglobulin (alpha2M) might reduce paracrine- and autocrine-stimulated Matrix Synthesis of cultured rat hepatic stellate cells (HSCs) by scavenging TGF-beta. METHODS AND RESULTS Using native agarose electrophoresis, we demonstrated that alpha2M binds [125I]-TGF-beta1 within minutes. Preincubation of transiently acidified supernatants of cultured Kupffer cells, secondary cultured (activated) HSC and platelet lysate with, respectively, 500 and 2000 microg mL-1 alpha2M significantly reduced the concentration of active TGF-beta1 in these media. As a consequence of TGF-beta scavenging by alpha2M, paracrine-stimulated proteoglycan Synthesis of primary cultured HSCs was reduced significantly. Furthermore, addition of 200 microg mL-1 alpha2M to passaged (activated) HSCs resulted in (a) a reduction in autocrine-stimulated extracellular Matrix Synthesis (proteoglycan -52%, fibronectin -55%) and (b) increased cell proliferation. A similar reduction in Matrix Synthesis was observed after the addition of 5 micromol L-1 TGF-beta1 antisense oligonucleotide to activated HSCs. CONCLUSION We conclude that alpha2M reduces paracrine-and autocrine-stimulated extracellular Matrix Synthesis of cultured HSCs by scavenging TGF-beta. These mechanisms might restrict liver fibrogenesis.
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Depending on their concentration oxidized low density lipoproteins stimulate extracellular Matrix Synthesis or induce apoptosis in human coronary artery smooth muscle cells.
Clinical chemistry and laboratory medicine, 1999Co-Authors: Max G. Bachem, Alexandra Schmid-kotsas, Daniela Wendelin, Wilhelm Schneiderhan, Cornelia Haug, Ulrike Zorn, Hans J. Gross, Adolf GrünertAbstract:Various lines of evidence indicate that oxidative stress resulting in lipid peroxidation and protein modification is involved in the pathogenesis of atherosclerosis and coronary heart disease. We have investigated the effect of modified (oxidized) low-density lipoproteins (oxLDL) on collagen and fibronectin Synthesis in cultured human coronary artery smooth muscle cells (HCA-SMC). As shown by immunofluorescence microscopy and time-resolved fluorescence immunoassay, oxLDL dose-dependently stimulated collagen type I and fibronectin Synthesis in cultured HCA-SMC. The effect on Matrix Synthesis was biphasic, with a maximum effect at concentrations between 1 and 10 μg/ml oxLDL. Higher oxLDL concentrations (>25 μg/ml) were cytotoxic. Beside oxLDL, malondialdehyde-modified LDL also stimulated extracellular Matrix Synthesis. In the presence of 100 μg/ml ascorbic acid, 25, 50 and 100 μg/ml oxLDL induced apoptosis within 6-8 hours (demonstrated by TUNEL-reaction, annexin-V binding and APO-2.7-expression), Apoptosis was not induced by normal (unmodified) LDL and malondialdehyde-modified LDL. The radical scavengers and antioxidants TROLOX and probucol and the hydrogen peroxide eliminator catalase significantly reduced oxLDL-induced apoptosis. Our results demonstrate that low concentrations of oxLDL are profibrogenic by stimulating extracellular Matrix Synthesis, whereas higher oxLDL concentrations induce oxidative stress and apoptosis in coronary artery smooth muscle cells. The profibrogenic effect might be relevant in the formation of atherosclerotic plaques, and the proapoptotic effect might contribute to an increased plaque vulnerability.
D F Wong - One of the best experts on this subject based on the ideXlab platform.
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A Matrix Synthesis approach to thermal placement
IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, 1998Co-Authors: Chris Chu, D F WongAbstract:In this paper, we consider the thermal placement problem for gate arrays. We introduce a new combinatorial optimization problem, Matrix Synthesis problem (MSP), to model the thermal placement problem. Given a list of mn nonnegative real numbers and an integer t, MSP constructs a m/spl times/n Matrix out of the given numbers such that the maximum sum among all t/spl times/t submatrices is minimized. We show that MSP is NP-complete and present several provably good approximation algorithms for the problem. We also demonstrate that our thermal placement strategy is flexible enough to allow simultaneous consideration of other objectives such as wiring.
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a Matrix Synthesis approach to thermal placement
International Symposium on Physical Design, 1997Co-Authors: Chris Chu, D F WongAbstract:In this paper, we consider the thermal placement problem for gate arrays. We introduce a new combinatorial opti- mization problem, Matrix Synthesis problem (MSP), to model the thermal placement problem. Given a list of nonnegative real numbers and an integer , MSP constructs a Matrix out of the given numbers such that the maximum sum among all submatrices is minimized. We show that MSP is NP-complete and present several provably good approximation algorithms for the problem. We also demonstrate that our thermal placement strategy is flexible enough to allow simultaneous consideration of other objectives such as wiring.
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ISPD - A Matrix Synthesis approach to thermal placement
Proceedings of the 1997 international symposium on Physical design - ISPD '97, 1997Co-Authors: Chris Chu, D F WongAbstract:In this paper, we consider the thermal placement problem for gate arrays. We introduce a new combinatorial opti- mization problem, Matrix Synthesis problem (MSP), to model the thermal placement problem. Given a list of nonnegative real numbers and an integer , MSP constructs a Matrix out of the given numbers such that the maximum sum among all submatrices is minimized. We show that MSP is NP-complete and present several provably good approximation algorithms for the problem. We also demonstrate that our thermal placement strategy is flexible enough to allow simultaneous consideration of other objectives such as wiring.