Provided herein are methods and kits for analyzing a biological sample obtained from a subject having, suspected of having, or being at risk for a disease associated with the contact activation system.

Disclosed are processes for the production of composition comprising one or more fructose amino acids, and related. Such a process may comprise the steps of: (a) providing plant material derived from a botanical source selected from plants of the families Solanaceae, Compositae, Asteraceae, Guttiferae, Umbelliferae, Papaveraceae, Vitidaceae or Acanthaceae; (b) extracting one or more fructose amino acid(s) from said plant material; and optionally, (c) detecting the presence and/or measuring the amount of said fructose amino acid(s) in the extract of step (b).

Nutritive polypeptides are provided herein. Also provided are various other embodiments including nucleic acids encoding the polypeptides, recombinant microorganisms that make the polypeptides, vectors for expressing the polypeptides, methods of making the polypeptides using recombinant microorganisms, compositions and formulations that comprise the polypeptides, and methods of using the polypeptides, compositions and formulations.

The present invention relates to the field of diagnostic methods. Specifically, the present invention contemplates a method for diagnosing heart failure in a subject and a method for monitoring progression or regression of heart failure in a subject. The invention also relates to tools for carrying out the aforementioned methods, such as diagnostic devices.

A protein assay method, including: 1) dissolving 4-hydroxybenzenesulfonic acid in an ethanol, methanol, or acetonitrile aqueous solution to prepare a hydrolysis reagent, adding a protein sample and the hydrolysis reagent to a hydrolysis tube, and uniformly mixing the protein sample and the hydrolysis reagent, charging argon or nitrogen into the hydrolysis tube to remove dissolved oxygen, sealing and drying the hydrolysis tube, and hydrolyzing the protein sample; 2) cooling the hydrolysis tube to room temperature, filtering and adding a resulting hydrolysate to a volumetric flask, washing the hydrolysis tube and a filter paper, collecting and adding a resulting washing solution to the volumetric flask to a constant volume; 3) drawing a hydrolysate solution from the volumetric flask, completely drying the hydrolysate solution to yield a solid product; and 4) diluting the solid product using a diluent, and analyzing amino acids of the solid product.

Provided are SpdE polypeptides and variants and nucleic acids encoding the SpdE polypeptides and variants. Also provided are vectors including one or more nucleic acids encoding a SpdE polypeptide or variant and cells including a nucleic acid encoding the SpdE polypeptide or variant, as well as cells expressing a SpdE polypeptide or variant and compositions including such cells and a pharmaceutically acceptable carrier. Finally, methods of detecting presence and/or amount of one or more amino acids in a sample are provided. The methods include contacting the sample with a SpdE protein, measuring diguanylate cyclase activity of the SpdE protein; and comparing the diguanylate cyclase activity of the SpdE protein to a control. The methods can utilize isolated SpdE protein or a cell expressing a SpdE protein.

An evaluating method includes an evaluating step of evaluating future risk of developing Alzheimer's disease for a subject to be evaluated having mild cognitive impairment using a concentration value of at least one of -ABA, Ala, Arg, Asn, Cit, Gln, Glu, Gly, His, Ile, Leu, Lys, Met, Orn, Phe, Pro, Ser, Thr, Trp, Tyr, Val, Cysteine, Taurine, bABA, Ethylglycine, Hypotaurine, 3-Me-His, 5-HydroxyTrp, aAiBA, and N8-Acetylspermidine in blood of the subject.

[Problem to be solved]

It is to provide a method for selectively and easily quantifying the L-form and/or D-form amino acids to be measured using an AARS with high sensitivity, and an amino acid quantification kit.

[Solution to Problem]

A method for quantifying amino acids (L-AA and/or D-AA) in a sample using an AARS, wherein the amino acids and the AARS are released from an aminoacyl AMP-AARS complex once formed, and they are used again for forming the aminoacyl AMP-AARS complex, so that reaction products such as pyrophosphoric acid to be measured can be ultimately produced up to a molar number larger than that of the amino acids contained in the sample, and an amino acid quantification kit for performing the method.

The present invention concerns an in vitro method for the determination of a neurodegenerative disease wherein separately from each other the content of kynurenine and kynurenic acid in a body fluid is determined and the quotient of the content of kynurenine to the content of kynurenic acid is calculated.

Dried blood spots (DBS) collected on a substrate material are used in the quantitation of amino acids, acylcarnitines, organic acids and numerous other small molecules. One of their main application areas is newborn screening. In order to properly quantitate small molecules of target analytes in DBS, stable isotope labeled internal standards that are typically deuterium or carbon 13 labeled versions of the desired target analytes to be quantitated are pre-loaded onto the substrate before blood collection. For example, phenylalanine with 6 Carbon 13 atoms is used as a reference to quantitate phenylalanine.