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X-ray Spectromicroscopy Study of Protein Adsorption to a Polystyrene-Polylactide Blend

Description: Synchrotron-based X-ray photoemission electron microscopy (X-PEEM) was used to study the adsorption of human serum albumin (HSA) to polystyrene-polylactide (40:60 PS-PLA, 0.7 wt percent) thin films, annealed under various conditions. The rugosity of the substrate varied from 35 to 90 nm, depending on the annealing conditions. However, the characteristics of the protein adsorption (amounts and phase preference) were not affected by the changes in topography. The adsorption was also not changed by the phase inversion which occured when the PS-PLA substrate was annealed above Tg of the PLA. The amount of protein adsorbed depended on whether adsorption took place from distilled water or phosphate buffered saline solution. These differences are interpreted as a result of ionic strength induced changes in the protein conformation in solution.
Date: June 9, 2010
Creator: Leung, Bonnie; Hitchcock, Adam; Cornelius, Rena; Brash, John; Scholl, Andreas & Doran, Andrew
Partner: UNT Libraries Government Documents Department

THE EFFECT OF EPINEPHRINE ON SERUM LIPOPROTEINS

Description: Epinephrine injection has been shown to produce a two and three fold increase of the higher Sf classes of serum lipoproteins in the rabbit. The previously observed elevation of serum lipids was confirmed. The hyperlipoproteinemia following epinephrine injection appears about the same time as in certain conditions of stress. (auth)
Date: November 21, 1957
Creator: Young, W. & Hayes, T.L.
Partner: UNT Libraries Government Documents Department

An Ultracentrifugal Method for the Determination of Serum Lipoproteins

Description: A convenient method was developed for the ultracentrifugal analysis of all classes of serum lipoproteins which requires a minimum of time, work and materials. The method utilizes the principle of flotation of lipoproteins in a medium of greater density than their own hydrated density. In this procedure the isolation and the analysis of lipoproteins are done in a NaBr mediumn of density 1.20 g/ml. The advantages of this procedure are compared with other available methods, and its application to studies on serum lipoprotein is discussed. (auth)
Date: September 29, 1958
Creator: Del Gatto, L.; Lindgren, F. T. & Nichols, A. V.
Partner: UNT Libraries Government Documents Department

Multispectral UV Fluorescence Detection of a Dilute Constituent in an Optically Dense Matrix

Description: Multispectral UV fluorescence measurements were made of an optically dense medium (fetal bovine serum, FBS) spiked with sodium salicylate at concentrate ions from 0.2 to 500 pg/ml . Analysis of the spectra show that, depending on experimental conditions, reasonably good estimates of concentration can be obtained across the entire range of concentrate ions. Experimental conditions required for recovering these estimates are demonstrated.
Date: October 15, 1998
Creator: Chan, O.H.; Gray, P.C., Wehlburg, C.M.; Rubenstein, R.; Tisone, G.C. & Wagner, J.S.
Partner: UNT Libraries Government Documents Department

Bone Marrow Activity in Vitro Under the Influence of Anemic Serum and Human Erythropoietin

Description: A method is described for observing the uptake of Fe by rat bone marrow cells in vitro. Results of experiments on effects of anemic serum and human erythropoietin are presented with a brief discussion. It is concluded that the differences in uptake of Fe/sup 59/ are the result of isotope dilution. (auth)
Date: May 1, 1960
Creator: Beck, J. S.
Partner: UNT Libraries Government Documents Department

A Method to Site-Specifically Identify and Quantitate Carbonyl End Products of Protein Oxidation Using Oxidation-Dependent Element Coded Affinity Tags (O-ECAT) and NanoLiquid Chromatography Fourier Transform Mass Spectrometry

Description: Protein oxidation is linked to cellular stress, aging, and disease. Protein oxidations that result in reactive species are of particular interest, since these reactive oxidation products may react with other proteins or biomolecules in an unmediated and irreversible fashion, providing a potential marker for a variety of disease mechanisms. We have developed a novel system to identify and quantitate, relative to other states, the sites of oxidation on a given protein. A specially designed Oxidation-dependent carbonyl-specific Element-Coded Affinity Mass Tag (O-ECAT), AOD, ((S)-2-(4-(2-aminooxy)-acetamido)-benzyl)-1, 4, 7, 10-tetraazacyclododecane-N, N', N'', N'''-tetraacetic acid, is used to covalently tag the residues of a protein oxidized to aldehyde or keto end products. After proteolysis, the resulting AOD-tagged peptides are affinity purified, and analyzed by nanoLC-FTICR-MS, which provides high specificity in extracting co-eluting AOD mass pairs with a unique mass difference and affords relative quantitation based on isotopic ratios. Using this methodology, we have mapped the surface oxidation sites on a model protein, recombinant human serum albumin (rHSA) in its native form (as purchased) and after FeEDTA oxidation. A variety of modified amino acid residues including lysine, arginine, proline, histidine, threonine, aspartic and glutamic acids, were found to be oxidized to aldehyde and keto end products. The sensitivity of this methodology is shown by the number of peptides identified, twenty peptides on the native protein and twenty-nine after surface oxidation using FeEDTA and ascorbate. All identified peptides map to the surface of the HSA crystal structure validating this method for identifying oxidized amino acids on protein surfaces. In relative quantitation experiments between FeEDTA oxidation and native protein oxidation, identified sites showed different relative propensities towards oxidation independent of amino acid residue. We expect to extend this methodology to study disease-related oxidation systems.
Date: August 25, 2005
Creator: Lee, S; Young, N L; Whetstone, P A; Cheal, S M; Benner, W H; Lebrilla, C B et al.
Partner: UNT Libraries Government Documents Department