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Martin M Knight - One of the best experts on this subject based on the ideXlab platform.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the crabtree effect but have different basal Oxygen Consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M Knight, David A LeeAbstract:In the absence of in vivo measurements, the Oxygen concentration within articular cartilage is calculated from the balance between cellular Oxygen Consumption and mass transfer. Current estimates of the Oxygen tension within articular cartilage are based on Oxygen Consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic Oxygen Consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced Oxygen Consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of Oxygen and glucose, which decrease with distance from the cartilage-synovial fluid interface. Thus, we tested the hypothesis that the Oxygen Consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater Oxygen Consumption than the superficial cells (V(max) of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 microm(3)/cell). Both populations expressed the Crabtree phenomena, with Oxygen Consumption increasing approximately 2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the Oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the crabtree effect but have different basal Oxygen Consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M KnightAbstract:In the absence of in vivo measurements, the Oxygen concentration within articular cartilage is calculated from the balance between cellular Oxygen Consumption and mass transfer. Current estimates of the Oxygen tension within articular cartilage are based on Oxygen Consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic Oxygen Consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced Oxygen Consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of Oxygen and glucose, which decrease with distance from the cartilage–synovial fluid interface. Thus, we tested the hypothesis that the Oxygen Consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater Oxygen Consumption than the superficial cells (Vmax of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 µm3/cell). Both populations expressed the Crabtree phenomena, with Oxygen Consumption increasing ∼2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the Oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues. J. Cell. Physiol. 223:630–639, 2010. © 2010 Wiley-Liss, Inc.
Hannah K Heywood - One of the best experts on this subject based on the ideXlab platform.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the crabtree effect but have different basal Oxygen Consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M Knight, David A LeeAbstract:In the absence of in vivo measurements, the Oxygen concentration within articular cartilage is calculated from the balance between cellular Oxygen Consumption and mass transfer. Current estimates of the Oxygen tension within articular cartilage are based on Oxygen Consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic Oxygen Consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced Oxygen Consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of Oxygen and glucose, which decrease with distance from the cartilage-synovial fluid interface. Thus, we tested the hypothesis that the Oxygen Consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater Oxygen Consumption than the superficial cells (V(max) of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 microm(3)/cell). Both populations expressed the Crabtree phenomena, with Oxygen Consumption increasing approximately 2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the Oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the crabtree effect but have different basal Oxygen Consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M KnightAbstract:In the absence of in vivo measurements, the Oxygen concentration within articular cartilage is calculated from the balance between cellular Oxygen Consumption and mass transfer. Current estimates of the Oxygen tension within articular cartilage are based on Oxygen Consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic Oxygen Consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced Oxygen Consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of Oxygen and glucose, which decrease with distance from the cartilage–synovial fluid interface. Thus, we tested the hypothesis that the Oxygen Consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater Oxygen Consumption than the superficial cells (Vmax of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 µm3/cell). Both populations expressed the Crabtree phenomena, with Oxygen Consumption increasing ∼2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the Oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues. J. Cell. Physiol. 223:630–639, 2010. © 2010 Wiley-Liss, Inc.
David A Lee - One of the best experts on this subject based on the ideXlab platform.
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both superficial and deep zone articular chondrocyte subpopulations exhibit the crabtree effect but have different basal Oxygen Consumption rates
Journal of Cellular Physiology, 2010Co-Authors: Hannah K Heywood, Martin M Knight, David A LeeAbstract:In the absence of in vivo measurements, the Oxygen concentration within articular cartilage is calculated from the balance between cellular Oxygen Consumption and mass transfer. Current estimates of the Oxygen tension within articular cartilage are based on Oxygen Consumption data from full-depth tissue samples. However, superficial and deep cell subpopulations of articular cartilage express intrinsic metabolic differences. We test the hypothesis that the subpopulations differ with respect to their intrinsic Oxygen Consumption rate. Chondrocytes from the full cartilage thickness demonstrate enhanced Oxygen Consumption when deprived of glucose, consistent with the Crabtree phenomena. Chondrocyte subpopulations differ in the prevailing availability of Oxygen and glucose, which decrease with distance from the cartilage-synovial fluid interface. Thus, we tested the hypothesis that the Oxygen Consumption of each subpopulation is modulated by nutrient availability, by examining the expression of the Crabtree effect. The deep cells had a greater Oxygen Consumption than the superficial cells (V(max) of 6.6 compared to 3.2 fmol/cell/h), consistent with our observations of mitochondrial volume (mean values 52.0 vs. 36.4 microm(3)/cell). Both populations expressed the Crabtree phenomena, with Oxygen Consumption increasing approximately 2.5-fold in response to glycolytic inhibition by glucose deprivation or 2-deoxyglucose. Over 90% of this increase was oligomycin-sensitive and thus accounted for by oxidative phosphorylation. The data contributes towards our understanding of chondrocyte energy metabolism and provides information valuable for the accurate calculation of the Oxygen concentration that the cells experience in vivo. The work has further application to the optimisation of bioreactor design and engineered tissues.
Mark R Holl - One of the best experts on this subject based on the ideXlab platform.
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a cellular isolation system for real time single cell Oxygen Consumption monitoring
Journal of the Royal Society Interface, 2008Co-Authors: Joe Dragavon, T W Molter, Mark R Holl, Sarah C Mcquaide, Cody Young, Timothy J Strovas, Meng Zhang, Brad T Cookson, Alex K Y JenAbstract:The development of a cellular isolation system (CIS) that enables the monitoring of single-cell Oxygen Consumption rates in real time is presented. The CIS was developed through a multidisciplinary effort within the Microscale Life Sciences Center (MLSC) at the University of Washington. The system comprises arrays of microwells containing Pt-porphyrin-embedded polystyrene microspheres as the reporter chemistry, a lid actuator system and a gated intensified imaging camera, all mounted on a temperature-stabilized confocal microscope platform. Oxygen Consumption determination experiments were performed on RAW264.7 mouse macrophage cells as proof of principle. Repeatable and consistent measurements indicate that the Oxygen measurements did not adversely affect the physiological state of the cells measured. The observation of physiological rates in real time allows studies of cell-to-cell heterogeneity in Oxygen Consumption rate to be performed. Such studies have implications in understanding the role of mitochondrial function in the progression of inflammatory-based diseases, and in diagnosing and treating such diseases.
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a new approach for measuring single cell Oxygen Consumption rates
International Conference on Robotics and Automation, 2008Co-Authors: T W Molter, Mark R Holl, Joe Dragavon, Sarah C Mcquaide, Judy B Anderson, A C Young, Lloyd W Burgess, Mary E Lidstrom, Deirdre R MeldrumAbstract:A novel system that has enabled the measurement of single-cell Oxygen Consumption rates is presented. The experimental apparatus includes a temperature controlled environmental chamber, an array of microwells etched in glass, and a lid actuator used to seal cells in the microwells. Each microwell contains an Oxygen sensitive platinum phosphor sensor used to monitor the cellular metabolic rates. Custom automation software controls the digital image data collection for Oxygen sensor measurements, which are analyzed using an image-processing program to yield the Oxygen concentration within each microwell versus time. Two proof-of-concept experiments produced Oxygen Consumption rate measurements for A549 human epithelial lung cancer cells of 5.39 and 5.27 fmol/min/cell, closely matching published Oxygen Consumption rates for bulk A549 populations.
T W Molter - One of the best experts on this subject based on the ideXlab platform.
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a cellular isolation system for real time single cell Oxygen Consumption monitoring
Journal of the Royal Society Interface, 2008Co-Authors: Joe Dragavon, T W Molter, Mark R Holl, Sarah C Mcquaide, Cody Young, Timothy J Strovas, Meng Zhang, Brad T Cookson, Alex K Y JenAbstract:The development of a cellular isolation system (CIS) that enables the monitoring of single-cell Oxygen Consumption rates in real time is presented. The CIS was developed through a multidisciplinary effort within the Microscale Life Sciences Center (MLSC) at the University of Washington. The system comprises arrays of microwells containing Pt-porphyrin-embedded polystyrene microspheres as the reporter chemistry, a lid actuator system and a gated intensified imaging camera, all mounted on a temperature-stabilized confocal microscope platform. Oxygen Consumption determination experiments were performed on RAW264.7 mouse macrophage cells as proof of principle. Repeatable and consistent measurements indicate that the Oxygen measurements did not adversely affect the physiological state of the cells measured. The observation of physiological rates in real time allows studies of cell-to-cell heterogeneity in Oxygen Consumption rate to be performed. Such studies have implications in understanding the role of mitochondrial function in the progression of inflammatory-based diseases, and in diagnosing and treating such diseases.
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a new approach for measuring single cell Oxygen Consumption rates
International Conference on Robotics and Automation, 2008Co-Authors: T W Molter, Mark R Holl, Joe Dragavon, Sarah C Mcquaide, Judy B Anderson, A C Young, Lloyd W Burgess, Mary E Lidstrom, Deirdre R MeldrumAbstract:A novel system that has enabled the measurement of single-cell Oxygen Consumption rates is presented. The experimental apparatus includes a temperature controlled environmental chamber, an array of microwells etched in glass, and a lid actuator used to seal cells in the microwells. Each microwell contains an Oxygen sensitive platinum phosphor sensor used to monitor the cellular metabolic rates. Custom automation software controls the digital image data collection for Oxygen sensor measurements, which are analyzed using an image-processing program to yield the Oxygen concentration within each microwell versus time. Two proof-of-concept experiments produced Oxygen Consumption rate measurements for A549 human epithelial lung cancer cells of 5.39 and 5.27 fmol/min/cell, closely matching published Oxygen Consumption rates for bulk A549 populations.
