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Hyoe Hatakeyama - One of the best experts on this subject based on the ideXlab platform.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC-Water systems with a Water content (W(c)=mass of Water/mass of dry sample, gg(-1)) in the range 0-2.0 was measured in the temperature range -150 to 50 degrees C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W(c) in the range 0.5-0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was approximately 0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:Abstract The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC–Water systems with a Water content ( W c = mass of Water/mass of dry sample, g g −1 ) in the range 0–2.0 was measured in the temperature range −150 to 50 °C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W c in the range 0.5–0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was ∼0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
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interaction between Water and hydrophilic polymers
Thermochimica Acta, 1998Co-Authors: Hyoe Hatakeyama, Tatsuko HatakeyamaAbstract:Abstract Various natural and synthetic polymers with hydrophilic groups, such as hydroxyl, carboxyl and carbonyl groups, have either a strong or weak interaction with Water. Thermal properties of polymers and Water are both markedly influenced through this interaction. The first-order phase transition of Water fractions closely associated with the polymer matrix is usually impossible to observe. Such fractions are called non-freezing Water. Less closely associated Water fractions exhibit melting/crystallization, showing considerable supercooling and significantly smaller enthalpy than that of bulk Water. These Water fractions are referred to as freezing Bound Water. The sum of the freezing Bound and non-freezing Water fractions is the Bound Water content. Water, whose melting/crystallization temperature and enthalpy are not significantly different from those of normal (bulk) Water, is designated as freezing Water. Bound Water in the Water-insoluble hydrophilic polymers, such as cellulose, lignin and poly(hydroxystyrene) derivatives, breaks hydrogen bonding between the hydroxyl groups of the polymers. The Bound Water content depends on the chemical and high-order structure of each polymer. Aqueous solutions of Water-soluble polyelectrolytes, such as hyaluronic acid, gellan gum, xanthan gum and poly(vinyl alcohol) form gels above a threshold concentration. In the above gels, Water mostly exists as the freezing Bound Water, playing an important role in the junction zone formation. It has also been observed that various kinds of polysaccharide polyelectrolytes with mono- and divalent cations, and other polyelectrolytes, such as polystyrene sulfonate, form thermotropic/lyotropic liquid crystals in the Water content, ranging from 0.5 to ca. 3.0 g of Water/g of polymer.
Tatsuko Hatakeyama - One of the best experts on this subject based on the ideXlab platform.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC-Water systems with a Water content (W(c)=mass of Water/mass of dry sample, gg(-1)) in the range 0-2.0 was measured in the temperature range -150 to 50 degrees C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W(c) in the range 0.5-0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was approximately 0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:Abstract The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC–Water systems with a Water content ( W c = mass of Water/mass of dry sample, g g −1 ) in the range 0–2.0 was measured in the temperature range −150 to 50 °C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W c in the range 0.5–0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was ∼0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
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interaction between Water and hydrophilic polymers
Thermochimica Acta, 1998Co-Authors: Hyoe Hatakeyama, Tatsuko HatakeyamaAbstract:Abstract Various natural and synthetic polymers with hydrophilic groups, such as hydroxyl, carboxyl and carbonyl groups, have either a strong or weak interaction with Water. Thermal properties of polymers and Water are both markedly influenced through this interaction. The first-order phase transition of Water fractions closely associated with the polymer matrix is usually impossible to observe. Such fractions are called non-freezing Water. Less closely associated Water fractions exhibit melting/crystallization, showing considerable supercooling and significantly smaller enthalpy than that of bulk Water. These Water fractions are referred to as freezing Bound Water. The sum of the freezing Bound and non-freezing Water fractions is the Bound Water content. Water, whose melting/crystallization temperature and enthalpy are not significantly different from those of normal (bulk) Water, is designated as freezing Water. Bound Water in the Water-insoluble hydrophilic polymers, such as cellulose, lignin and poly(hydroxystyrene) derivatives, breaks hydrogen bonding between the hydroxyl groups of the polymers. The Bound Water content depends on the chemical and high-order structure of each polymer. Aqueous solutions of Water-soluble polyelectrolytes, such as hyaluronic acid, gellan gum, xanthan gum and poly(vinyl alcohol) form gels above a threshold concentration. In the above gels, Water mostly exists as the freezing Bound Water, playing an important role in the junction zone formation. It has also been observed that various kinds of polysaccharide polyelectrolytes with mono- and divalent cations, and other polyelectrolytes, such as polystyrene sulfonate, form thermotropic/lyotropic liquid crystals in the Water content, ranging from 0.5 to ca. 3.0 g of Water/g of polymer.
Richard G Spencer - One of the best experts on this subject based on the ideXlab platform.
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mapping proteoglycan Bound Water in cartilage improved specificity of matrix assessment using multiexponential transverse relaxation analysis
Magnetic Resonance in Medicine, 2011Co-Authors: David A Reiter, Remigio A Roque, Ping Chang Lin, Onyi N Irrechukwu, Stephen B Doty, Dan L Longo, Nancy Pleshko, Richard G SpencerAbstract:Association of MR parameters with cartilage matrix components remains an area of ongoing investigation. Multiexponential analysis of nonlocalized transverse relaxation data has previously been used to quantify Water compartments associated with matrix macromolecules in cartilage. We extend this to mapping the proteoglycan (PG)-Bound Water fraction in cartilage, using mature and young bovine nasal cartilage model systems, toward the goal of matrix component-specific imaging. PG-Bound Water fraction from mature and young bovine nasal cartilage was 0.31 ± 0.04 and 0.22 ± 0.06, respectively, in agreement with biochemically derived PG content and PG-to-Water weight ratios. Fourier transform infrared imaging spectroscopic-derived PG maps normalized by Water content (IR-PG(ww) ) showed spatial correspondence with PG-Bound Water fraction maps. Extensive simulation analysis demonstrated that the accuracy and precision of our determination of PG-Bound Water fraction was within 2%, which is well-within the observed tissue differences. Our results demonstrate the feasibility of performing imaging-based multiexponential analysis of transverse relaxation data to map PG in cartilage.
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mapping proteoglycan Bound Water in cartilage improved specificity of matrix assessment using multiexponential transverse relaxation analysis
Magnetic Resonance in Medicine, 2011Co-Authors: David A Reiter, Remigio A Roque, Ping Chang Lin, Onyi N Irrechukwu, Stephen B Doty, Dan L Longo, Nancy Pleshko, Richard G SpencerAbstract:Association of MR parameters with cartilage matrix components remains an area of ongoing investigation. Multiexponential analysis of non-localized transverse relaxation data has previously been used to quantify Water compartments associated with matrix macromolecules in cartilage. We extend this to mapping the proteoglycan-Bound Water fraction (wPG) in cartilage, using mature and young bovine nasal cartilage model systems, towards the goal of matrix component-specific imaging. wPG from mature and young bovine nasal cartilage was 0.3±0.04 and 0.22±0.06, respectively, in agreement with biochemically-derived proteoglycan content and proteoglycan-to-Water weight ratios. Fourier transform infrared imaging spectroscopic-derived proteoglycan maps normalized by Water content (IR-PGww) showed spatial correspondence with wPG maps. Extensive simulation analysis demonstrated that the accuracy and precision of our determination of wPG was within 2%, which is substantially smaller than the observed tissue differences. Our results demonstrate the feasibility of performing imaging-based multiexponential analysis of transverse relaxation data to map proteoglycan in cartilage.
Masaru Tanaka - One of the best experts on this subject based on the ideXlab platform.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:Abstract The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC–Water systems with a Water content ( W c = mass of Water/mass of dry sample, g g −1 ) in the range 0–2.0 was measured in the temperature range −150 to 50 °C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W c in the range 0.5–0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was ∼0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
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studies on Bound Water restrained by poly 2 methacryloyloxyethyl phosphorylcholine comparison with polysaccharide Water systems
Acta Biomaterialia, 2010Co-Authors: Tatsuko Hatakeyama, Masaru Tanaka, Hyoe HatakeyamaAbstract:The structural change of Water restrained by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) was investigated by differential scanning calorimetry (DSC), since the biocompatibility of PMPC and related biopolymers is affected by the structure of Water on the polymer surface. The phase transition behaviour of PMPC-Water systems with a Water content (W(c)=mass of Water/mass of dry sample, gg(-1)) in the range 0-2.0 was measured in the temperature range -150 to 50 degrees C. Glass transition, cold crystallization and melting were observed. Cold crystallization, which has been suggested as an index of biocompatibility, was detected for PMPC with a W(c) in the range 0.5-0.9. The amounts of two types of Bound Water, non-freezing Water and freezing Bound Water, were calculated from the melting enthalpy. The amount of non-freezing Water of PMPC was approximately 0.48. It was found that the phase transition behaviour and amount of Bound Water of PMPC were quite similar to those of Water-soluble polysaccharide electrolytes. The results indicate that the Bound Water, not the free Water, is restrained by PMPC.
David A Reiter - One of the best experts on this subject based on the ideXlab platform.
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mapping proteoglycan Bound Water in cartilage improved specificity of matrix assessment using multiexponential transverse relaxation analysis
Magnetic Resonance in Medicine, 2011Co-Authors: David A Reiter, Remigio A Roque, Ping Chang Lin, Onyi N Irrechukwu, Stephen B Doty, Dan L Longo, Nancy Pleshko, Richard G SpencerAbstract:Association of MR parameters with cartilage matrix components remains an area of ongoing investigation. Multiexponential analysis of nonlocalized transverse relaxation data has previously been used to quantify Water compartments associated with matrix macromolecules in cartilage. We extend this to mapping the proteoglycan (PG)-Bound Water fraction in cartilage, using mature and young bovine nasal cartilage model systems, toward the goal of matrix component-specific imaging. PG-Bound Water fraction from mature and young bovine nasal cartilage was 0.31 ± 0.04 and 0.22 ± 0.06, respectively, in agreement with biochemically derived PG content and PG-to-Water weight ratios. Fourier transform infrared imaging spectroscopic-derived PG maps normalized by Water content (IR-PG(ww) ) showed spatial correspondence with PG-Bound Water fraction maps. Extensive simulation analysis demonstrated that the accuracy and precision of our determination of PG-Bound Water fraction was within 2%, which is well-within the observed tissue differences. Our results demonstrate the feasibility of performing imaging-based multiexponential analysis of transverse relaxation data to map PG in cartilage.
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mapping proteoglycan Bound Water in cartilage improved specificity of matrix assessment using multiexponential transverse relaxation analysis
Magnetic Resonance in Medicine, 2011Co-Authors: David A Reiter, Remigio A Roque, Ping Chang Lin, Onyi N Irrechukwu, Stephen B Doty, Dan L Longo, Nancy Pleshko, Richard G SpencerAbstract:Association of MR parameters with cartilage matrix components remains an area of ongoing investigation. Multiexponential analysis of non-localized transverse relaxation data has previously been used to quantify Water compartments associated with matrix macromolecules in cartilage. We extend this to mapping the proteoglycan-Bound Water fraction (wPG) in cartilage, using mature and young bovine nasal cartilage model systems, towards the goal of matrix component-specific imaging. wPG from mature and young bovine nasal cartilage was 0.3±0.04 and 0.22±0.06, respectively, in agreement with biochemically-derived proteoglycan content and proteoglycan-to-Water weight ratios. Fourier transform infrared imaging spectroscopic-derived proteoglycan maps normalized by Water content (IR-PGww) showed spatial correspondence with wPG maps. Extensive simulation analysis demonstrated that the accuracy and precision of our determination of wPG was within 2%, which is substantially smaller than the observed tissue differences. Our results demonstrate the feasibility of performing imaging-based multiexponential analysis of transverse relaxation data to map proteoglycan in cartilage.