A method of treating an inflammatory condition with a hydroxytyrosol-rich composition. Improvement is monitored as a reduction in the levels of a biochemical marker such as homocysteine or C-reactive protein. The composition may be administered in an amount and for a period sufficient to effect a drop in the level of the biochemical marker.

Compositions and methods for determining the level of thiol and disulfide containing molecules in a sample are provided. The compositions and methods can be used to determine the level of oxidative stress in a subject with or without antioxidant treatment. Also provided are biomarkers of oxidative stress.

The present invention discloses compounds of Formula-A and its copper complex of general Formula-B. The compound of general Formula-B is used in the selective detection of homocysteine in aqueous medium at physiological pH without any interference from other challenging amino acids and thiols. Using compounds of general Formula-B, specific detection of homocysteine under UV light in aqueous solution is also possible by the naked eyes.

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Examination of a test sample to determine the presence or quantity of succination of proteins is described. Examination can be via protein hydrolysis in total succination determination or via enzymatic digestion of isolated proteins and determination of the presence or quantity of modified peptides. The methods can be utilized for determination of excessive succination of lymph system proteins, which can be utilized in prevention or early detection of lymphopenia. Methods can be utilized for test samples of subjects under treatment with dimethyl fumarate suffering from multiple sclerosis. Methods can be utilized as a determination that treatment of the subject with DMF should be slowed or stopped.

The present disclosure provides methods of treating patients having a respiratory disorder, methods of identifying subjects having an increased risk of developing a respiratory disorder, and methods of detecting human Arachidonate 15-Lipoxygenase (ALOX15) variant nucleic acid molecules and variant polypeptides.

The present invention relates to a compound (L) for selective determination of free cysteine and a process for the preparation thereof. ##STR00001##
wherein R1 is selected from benzene, toluene, naphthalene and pyrene.

The present invention relates to methods for detecting sulfenylation within thiol groups in proteins, metabolites, or materials. Protein sulfenylation (Cys-SOH) describes the reversible post-translational modification of protein thiols by hydrogen peroxide, and plays a central role in oxidative signaling (see, e.g., Paulsen, C. E. & Carroll, K. S. 2013 Chemical Reviews 113, 4633-679). Growth factor stimulation activates NADPH oxidase enzymes, releasing a local burst of hydrogen peroxide, which transiently oxidizes the nuclcophilic cysteine of protein phosphatases and other proximal redox active thiols (see, e.g., Paulsen, C. E. et al., 2012 Nature Chemical Biology 8, 57-64). In addition to masking functional cysteine's, sulfenylation is also a critical intermediate towards irreversible cysteine oxidation.

Compositions and methods for analyzing disulfide bonds are provided. An exemplary method includes preparing peptide standards having no disulfide bonds, scrambled disulfide bond peptide standards, and native disulfide bond peptide standards according to the sequence of the region of the protein drug product that includes the disulfide bond, digesting a sample of protein drug product into peptides, separating the protein drug product peptides, analyzing the protein drug product peptides and the peptide standards, identifying scrambled and native disulfide bond peptides by retention time, and quantifying the level of scrambled disulfide bond peptides.

Compositions and methods for identifying free thiols in protein are provided. An exemplary method labeling peptides with a tag to identify free thiols and a tag to identify native disulfide bonds and analyzing the tags using targeted MS.sup.2. In one embodiment, the method provides complete coverage of all 32 cysteine residues in an IgG molecule. In other embodiments the method covers the 16 cysteine residues on the heavy and light chains in an IgG molecule. In another embodiment, the method covers the 5 cysteine residues on each light chain of an IgG molecule. In another embodiment, the method covers the 11 cysteine residues on each heavy chain of an IgG molecule.

The present invention includes a method of detecting free and total NAC, NACA, or both in a biological sample and/or the effectiveness of a treatment with NAC, NACA, or diNACA comprising: adding 2-chloro-1-methylpyridinium iodide (CMPI) to a biological sample suspected of having NAC or NACA to convert free thiols into stable thioethers; precipitating the protein in the sample; extracting the stable thioethers and separating into a first and a second extract; detecting the thioether derivatives from the first extract with LC-MS/MS; reducing from the second extract free thiols by adding tris(2-carboxyethyl)phosphine (TCEP) followed by converting to stable thioethers with CMPI; detecting the disulfides reduced to free thioether derivatives from the second extract with LC-MS/MS; and calculating from the LC-MS/MS and TCEP of the first and second extracts a free and a total sample NAC or NACA.