David Meadows - Academia.edu (original) (raw)
Papers by David Meadows
FIELD: medicine. SUBSTANCE: group of inventions relates to the field of medicine, specifically to... more FIELD: medicine. SUBSTANCE: group of inventions relates to the field of medicine, specifically to ophthalmology, and is intended for the treatment of dry eyes. Ophthalmic composition for treating dry eyes contains 0.1 to 0.2 w/v% galactomannan, 0.05 to 0.5 w/v% hyaluronic acid, and 1.0 to 2.0 w/v% sorbitol. In order to treat dry eyes, the composition is administered to the eyes of a patient in need of such treatment. EFFECT: use of the group of inventions makes improves the efficiency of treating dry eyes by improving the protection of the cornea from dehydration, and also improves protection due to retention of the composition on the surface of the eye. 8 cl, 7 tbl, 4 dwg, 3 ex
The present invention is an ionized therapeutic agent, the ionic component and the nine ares aque... more The present invention is an ionized therapeutic agent, the ionic component and the nine ares aqueous medicament containing gum pharmaceutical composition. Gu are limited interaction between the black ionized therapeutic agent and the ionic components and to impart stability to the composition present in the composition having a sufficient concentration. The composition preferably has a pH at or near physiological. The aqueous pharmaceutical composition has been found to be particularly useful as a water-based eye, ear or nose composition. The pharmaceutical compositions, due to its characteristics, is especially suitable as an ophthalmic composition.
The present invention relates to a viscosity suitable for ophthalmic preparations to stabilize op... more The present invention relates to a viscosity suitable for ophthalmic preparations to stabilize ophthalmic preparations and for drug delivery. And the agent comprises a borate source, such as lactic acid and met to go, such as guar or hydroxypropyl guar. Formulation further comprises a diol alcohol, and optionally a second pharmaceutically acceptable cations, such as magnesium chloride, salts such as sorbitol.
Journal of Immunological Methods, Oct 1, 1991
Biotechnology and Bioengineering, May 1, 1991
Biophysical Journal, 2012
Talanta, Feb 1, 1988
A new optical homogeneous biochemical method for the assay of glucose has been developed, based o... more A new optical homogeneous biochemical method for the assay of glucose has been developed, based on fluorescence energy transfer between a glucose analog, dextran labeled with fluorescein isothiocyanate (FITCdextran), and a glucose-receptor protein, Rhodamine-labeled Concanavalin A (RhConA). When FITCdextran binds to RlConA in solution, and is light-activated, the FITC label transfers its absorbed energy to the Rhodamine label, which then emits light according to its own characteristic fluorescence spectrum. When glucose is added to this solution, the FITC fluorescence intensity increases as FITCdextran is released from the RhConA and is replaced by glucose. Thus it is possible to determine glucose concentrations directly from the level of FITC fluorescence.
Colloids and Surfaces B: Biointerfaces, 2005
The wettability of poly[2-hydroxyethyl methacrylate-co-methacrylic acid] (pHEMA-MAA) soft contact... more The wettability of poly[2-hydroxyethyl methacrylate-co-methacrylic acid] (pHEMA-MAA) soft contact lenses was investigated in the absence and presence of block copolymer surfactants and lysozyme using the sessile drop method. The advancing dynamic contact angles (Thetaw/a) values are reported for water as a function of sequential wetting and drying cycles. The Thetaw/a values for the pHEMA-MAA in the absence of surfactant and lysozyme increased from approximately 20 degrees to 100 degrees as the number of cycles increased from two to ten, and they were independent of the pHEMA-MAA bulk water content. The change from the highly hydrophilic to hydrophobic pHEMA-MAA surface could not be reversed using the sequential wetting and drying cycles even under repeated exposures to saline solution. The effect of block copolymer surfactants with different molecular weights (MW) and hydrophilic-lipophilic balance (HLB) values on the pHEMA-MAA wettability were also studied. Low Theta(w/a) values were observed for pHEMA-MAA hydrogels that were treated with T1304 (MW 10500, HLB 14) and T904 (MW 6700, HLB 15). The surface tension data indicated that these surfactants were incompletely desorbed from the pHEMA-MAA and that the rate of desorption was slow in the timescale of the cycling experiments. Comparatively, poor wettability was observed for pHEMA-MAA surfaces presoaked in T304 (MW 1650, HLB 16) and T1107 (MW 15000, HLB 24) as Thetaw/a values greater than 90 degrees were measured for these surfactants. The surface tension data indicated that the rate of desorption of T304 and T1107 from the pHEMA-MAA was rapid and that they had a low affinity to the pHEMA-MAA. High contact angles were observed for the pHEMA-MAA hydrogels treated with lysozyme and also for the T1107 presoaked pHEMA-MAA that was also treated with lysozyme. Zero wetting angles throughout the sequential cycling were observed for the T1304 pre-treated pHEMA-MAA that had been treated with lysozyme. These results suggested that the adsorbed lysozyme on the pHEMA-MAA hydrogel had no significant influence on its wetting properties when the hydrogel was pre-treated with T1304.
Analytica Chimica Acta, Aug 1, 1993
Optical fiber biosensors based on fluorescence assays have several distinct advantages when measu... more Optical fiber biosensors based on fluorescence assays have several distinct advantages when measuring biological analytes such as metabolites, cofactors, toxins, etc. Not only are optical signals immune to electronic interferences, but the polychromatic nature of most fluorochemical assays provides more potentially useful data about the system being studied. One of the most common difficulties normally encountered with optical biosensors is the inability to routinely recalibrate the optical and electronic components of the system throughout the life of the sensor. With this in mind, an optical fiber biosensor system for glucose has been constructed along with the peripheral electronic instrumentation. The biochemical assay is based on an homogeneous singlet/singlet energy transfer affinity assay. The sensor probe indirectly measures glucose concentrations from the level of fluorescence quenching caused by the homogeneous competition assay between TRITC labeled concanavalin A (receptor) and FITC labeled Dextran (ligand). The FITC signal is used as an indicator for glucose concentrations and the TRITC signal is used for internal calibration. Chemical derivatization procedures using succinic anhydride were developed to prevent aggregation of the receptor protein in solution, and the TRITC/ConA ratios were optimized to achieve the best sensor performance. Using this sensor system, the FITC-Dextran detection limit was 0.05 bg/ml and glucose concentrations up to 1600 mg/dl could be detected with a time response of approximately 10 min.
FIELD: medicine. SUBSTANCE: group of inventions relates to the field of medicine, specifically to... more FIELD: medicine. SUBSTANCE: group of inventions relates to the field of medicine, specifically to ophthalmology, and is intended for the treatment of dry eyes. Ophthalmic composition for treating dry eyes contains 0.1 to 0.2 w/v% galactomannan, 0.05 to 0.5 w/v% hyaluronic acid, and 1.0 to 2.0 w/v% sorbitol. In order to treat dry eyes, the composition is administered to the eyes of a patient in need of such treatment. EFFECT: use of the group of inventions makes improves the efficiency of treating dry eyes by improving the protection of the cornea from dehydration, and also improves protection due to retention of the composition on the surface of the eye. 8 cl, 7 tbl, 4 dwg, 3 ex
The present invention is an ionized therapeutic agent, the ionic component and the nine ares aque... more The present invention is an ionized therapeutic agent, the ionic component and the nine ares aqueous medicament containing gum pharmaceutical composition. Gu are limited interaction between the black ionized therapeutic agent and the ionic components and to impart stability to the composition present in the composition having a sufficient concentration. The composition preferably has a pH at or near physiological. The aqueous pharmaceutical composition has been found to be particularly useful as a water-based eye, ear or nose composition. The pharmaceutical compositions, due to its characteristics, is especially suitable as an ophthalmic composition.
The present invention relates to a viscosity suitable for ophthalmic preparations to stabilize op... more The present invention relates to a viscosity suitable for ophthalmic preparations to stabilize ophthalmic preparations and for drug delivery. And the agent comprises a borate source, such as lactic acid and met to go, such as guar or hydroxypropyl guar. Formulation further comprises a diol alcohol, and optionally a second pharmaceutically acceptable cations, such as magnesium chloride, salts such as sorbitol.
Journal of Immunological Methods, Oct 1, 1991
Biotechnology and Bioengineering, May 1, 1991
Biophysical Journal, 2012
Talanta, Feb 1, 1988
A new optical homogeneous biochemical method for the assay of glucose has been developed, based o... more A new optical homogeneous biochemical method for the assay of glucose has been developed, based on fluorescence energy transfer between a glucose analog, dextran labeled with fluorescein isothiocyanate (FITCdextran), and a glucose-receptor protein, Rhodamine-labeled Concanavalin A (RhConA). When FITCdextran binds to RlConA in solution, and is light-activated, the FITC label transfers its absorbed energy to the Rhodamine label, which then emits light according to its own characteristic fluorescence spectrum. When glucose is added to this solution, the FITC fluorescence intensity increases as FITCdextran is released from the RhConA and is replaced by glucose. Thus it is possible to determine glucose concentrations directly from the level of FITC fluorescence.
Colloids and Surfaces B: Biointerfaces, 2005
The wettability of poly[2-hydroxyethyl methacrylate-co-methacrylic acid] (pHEMA-MAA) soft contact... more The wettability of poly[2-hydroxyethyl methacrylate-co-methacrylic acid] (pHEMA-MAA) soft contact lenses was investigated in the absence and presence of block copolymer surfactants and lysozyme using the sessile drop method. The advancing dynamic contact angles (Thetaw/a) values are reported for water as a function of sequential wetting and drying cycles. The Thetaw/a values for the pHEMA-MAA in the absence of surfactant and lysozyme increased from approximately 20 degrees to 100 degrees as the number of cycles increased from two to ten, and they were independent of the pHEMA-MAA bulk water content. The change from the highly hydrophilic to hydrophobic pHEMA-MAA surface could not be reversed using the sequential wetting and drying cycles even under repeated exposures to saline solution. The effect of block copolymer surfactants with different molecular weights (MW) and hydrophilic-lipophilic balance (HLB) values on the pHEMA-MAA wettability were also studied. Low Theta(w/a) values were observed for pHEMA-MAA hydrogels that were treated with T1304 (MW 10500, HLB 14) and T904 (MW 6700, HLB 15). The surface tension data indicated that these surfactants were incompletely desorbed from the pHEMA-MAA and that the rate of desorption was slow in the timescale of the cycling experiments. Comparatively, poor wettability was observed for pHEMA-MAA surfaces presoaked in T304 (MW 1650, HLB 16) and T1107 (MW 15000, HLB 24) as Thetaw/a values greater than 90 degrees were measured for these surfactants. The surface tension data indicated that the rate of desorption of T304 and T1107 from the pHEMA-MAA was rapid and that they had a low affinity to the pHEMA-MAA. High contact angles were observed for the pHEMA-MAA hydrogels treated with lysozyme and also for the T1107 presoaked pHEMA-MAA that was also treated with lysozyme. Zero wetting angles throughout the sequential cycling were observed for the T1304 pre-treated pHEMA-MAA that had been treated with lysozyme. These results suggested that the adsorbed lysozyme on the pHEMA-MAA hydrogel had no significant influence on its wetting properties when the hydrogel was pre-treated with T1304.
Analytica Chimica Acta, Aug 1, 1993
Optical fiber biosensors based on fluorescence assays have several distinct advantages when measu... more Optical fiber biosensors based on fluorescence assays have several distinct advantages when measuring biological analytes such as metabolites, cofactors, toxins, etc. Not only are optical signals immune to electronic interferences, but the polychromatic nature of most fluorochemical assays provides more potentially useful data about the system being studied. One of the most common difficulties normally encountered with optical biosensors is the inability to routinely recalibrate the optical and electronic components of the system throughout the life of the sensor. With this in mind, an optical fiber biosensor system for glucose has been constructed along with the peripheral electronic instrumentation. The biochemical assay is based on an homogeneous singlet/singlet energy transfer affinity assay. The sensor probe indirectly measures glucose concentrations from the level of fluorescence quenching caused by the homogeneous competition assay between TRITC labeled concanavalin A (receptor) and FITC labeled Dextran (ligand). The FITC signal is used as an indicator for glucose concentrations and the TRITC signal is used for internal calibration. Chemical derivatization procedures using succinic anhydride were developed to prevent aggregation of the receptor protein in solution, and the TRITC/ConA ratios were optimized to achieve the best sensor performance. Using this sensor system, the FITC-Dextran detection limit was 0.05 bg/ml and glucose concentrations up to 1600 mg/dl could be detected with a time response of approximately 10 min.