319 results about "Methionine+Homocysteine" patented technology

The disclosed methods and compositions for reducing cardiovascular risk factors in mammals generally includes using genistein to modulate various inflammatory and cardiovascular risk markers including: homocysteine, C-reactive protein, fibrinogen, sex hormone-binding globulin, fasting glucose, insulin, insulin resistance, and osteoprotegerin.

Described herein is a method for reducing levels of the harmful metabolic waste product of S-adenosylmethionine (SAMe), homocysteine, and provide vitamin and other nutritional co-factors that reduce the production of homocysteine and either re-methylate homocysteine back to S-adenosylmethionine, or facilitate its conversion downstream to cystathione. The method of the invention may be achieved by administering 5-methyl tetrahydrofolate, methylcobalamin, and one or more compounds selected from the group consisting of betaine, pyridoxal-5-phosphate, N-acetyl-cysteine, and other cofactors.

The invention relates to a method for determining homocysteine concentration in samples in which homocysteine is condensed using an enzyme cystathionine .beta. sythase to form cystathionine. Pyruvate and/or ammonia are released from cystathionine by action of an enzyme, cystathionine .beta. lyase, and homocysteine is regenerated. The release of pyruvate and/or ammonia can be correlated to the concentration of homocysteine present in the sample.

The present invention provides novel glutathione-dependent formaldehyde dehydrogenase that makes possible quantitative measurement of formaldehyde by cycling reaction, and a determination method of formaldehyde and biological components, such as creatinine, creatine, homocysteine and the like, which produces formaldehyde as a reaction intermediate. In addition, the present invention provides a reagent kit for the above-mentioned determination method. The present invention provides a novel determination method of a homocysteine using transferase utilizing homocysteine and other compound as a pair of substrates. Particularly, the present invention provides a determination method of homocysteine which includes bringing betaine-homocysteine methyltransferase and dimethylglycine oxidase into contact with a sample and measuring produced hydrogen peroxide or formaldehyde. Moreover, the present invention provides novel dimethylglycine oxidase stable to thiol compound, which is suitably used for the measurement. The present invention provides a reagent kit used for any of the above-mentioned determination methods of homocysteines.

This invention relates to a nucleic acid fragment encoding a plant 5-methyltetra-hydropteroyltriglutamate-homocysteine methyltransferase or methionine synthase. The invention also includes chimeric genes, a first encoding a plant methionine synthase (MS) gene, a second encoding a plant cystathionine γ-synthase (CS) gene, a third encoding feedback-insensitive aspartokinase (AK) or bifunctional feedback-insensitive aspartokinase-homoserine dehydrogenase (AK-HDH), which is operably linked to a plant chloroplast transit sequence, and a fourth encoding a methionine-rich protein, all operably linked to plant seed-specific regulatory sequences. Methods for their use to produce increased levels of methionine in the seeds of transformed plants are provided.

This invention features our discovery on usages of Methylenetetrahydrofolate Reductase (MTHFR) gene polymorphisms in predicting homocysteine (Hcy) level and/or incidence and prognosis of diseases associated with increased Hcy level in a subject, as well as predicting treatment effects of medicines in the category of Angiotension Converting Enzyme Inhibihor (ACEI) with and without combination with B Vitamins. This invention also features our discovery on laboratory and analytical methods that are essential to the above described usages of MTHFR gene polymorphisms. In addition, this invention features a kit that has translated the above discoveries into a practical and reliable tool that can be applied to accomplish the above described usages of MTHFR gene polymorphisms. This invention represents an important step in realizing personalized medicine, with the goal to tailor diagnosis, prevention and treatment strategy to meet individual needs.

1. The present invention provides compositions and methods for reversibly inhibiting S-adenosyl-L-homocysteine (SAH) hydrolase. The compounds of the present invention can be used as an anti-hemorrhagic viral infection agent, an immunosuppressant, a homocysteine lowering agent, or an anti-neoplasm agent. The compositions and methods of the present invention can be used for the prevention and treatment of hemorrhagic virus infection, autoimmune diseases, autograft rejection, neoplasm, hyperhomocysteineuria, cardiovascular disease, stroke, Alzheimer's disease, multiple sclerosis or diabetes. The compound of the present invention and/or used in the present invention has the formula (I):

The invention discloses a multifunctional fluorescent molecular probe for simultaneously distinguishing and detecting cysteine (Cys), homocysteine (Hcy) and glutathione (GSH) in cells by using three different fluorescent emission signals. The structural formula of the molecular probe is shown as follows: (the formula is shown in the description). Under the same detection conditions, the probe cangenerate a product with different fluorescence properties by carrying out different chemical reactions between the probe and Cys, Hcy and GSH, and emit different fluorescence signals under the excitation of different excitation wavelengths, so that the aim of simultaneously distinguishing and detecting the three biological thiols is achieved. After a mixture of the three thiols is added for reacting at room temperature for 15 minutes, blue fluorescence with the wavelength of 457nm is emitted for detecting the Cys at 360nm excitation wavelength; under the condition of 480nm excitation wavelength, 559nm yellow-green fluorescence is emitted for detecting the Hcy; under the condition of 400nm excitation wavelength, 529nm green fluorescence is emitted for detecting the GSH; the molecular probehas extremely-high sensitivity and selectivity to the Cys, the Hcy and the GSH and is successfully used for fluorescence imaging analysis of the Cys, the HCY and the GSH in different living cells.

The invention provides a homocysteine dry chemical detection strip and a preparation method thereof. The invention aims to provide a detection strip and a preparation method thereof for fast semiquantitatively/quantitatively detecting homocysteine. The strip is composed of an elongated upper support layer, an elongated lower support layer and test layers in the middle and is divided into a hand-held area and a test area. A diffusion layer, a filtration layer, an enzyme reagent layer and a colour development reagent layer are arranged in the test area from top to bottom. Various grid materials of synthetic fibre materials can be used to prepare the diffusion layer, various filterable materials for separating blood can be used to prepare the filtration layer, and various asymmetric synthetic membranes can be used to prepare the enzyme reagent layer and the colour development reagent layer. A loading hole is arranged in the upper support layer, a sample is sent from the loading pole to the diffusion layer, the sample then permeates into the filtration layer, the enzyme reagent layer and the colour development reagent layer, chemical reactions are performed in the enzyme reagent layer and the colour development reagent layer to change the colour, and the change of optical density in reaction process can be tested through a test pole of the lower support layer.

The present invention provides an enzymatic cycling assay for assessing the amount of homocysteine and/or cystathionine in a solution such as blood, blood derivatives, or urine. The assay comprises the steps of contacting the solution containing homocysteine and/or cystathionine to form a reaction mixture, with CBS, or a derivative thereof, L-serine, and CBL, or a derivative thereof, for a time period sufficient to catalyze the cyclical conversion of homocysteine form to cystathionine and the reconversion of cystathionine to homocysteine with the production of pyruvate and ammonia; determining the amount of homocysteine and/or ammonia present in the reaction mixture; and determining the amount of homocysteine and/or cystathionine present in the solution based on the amount of pyruvate and/or ammonia formed. Expression vectors and isolation procedures for CBS, or derivatives thereof, and CBL, or derivatives thereof, are also provided as well as test kits for carrying out the assay. In preferred embodiments, the assays can be conducted in 15 minutes or less, with a minimum of enzyme usage.

The invention relates to the technical field of chemical sensor, in particular to a phosphorescent chemical sensor for qualitatively detecting homocysteine and an application thereof. Aldehyde group of iridium complex can take cyclization with amido and hydrosulphonyl in the homocysteine to be transformed into hexahydroxy heterocycle and transformed into another compound. The original iridium complex is conjugated with a benzene ring and the aldehyde group and represents as weak red fluorescence while the compound obtained after reaction is not conjugated with the aldehyde group and represents as strong green fluorescence. Ultraviolet and phosphorescent spectrum is used for detecting the result that the complex identifies the homocysteine, thereby showing that the complex has specific response towards the homocysteine, has high sensitivity and can be identified by naked eye, and furthermore, the complex can distinguish cysteine which has a structure very similar as the homocysteine.

The invention relates to a stable kit for detecting homocysteine, and belongs to the technical field of medical science examination and determination. The stable kit for detecting homocysteine comprises a reagent 1 and a reagent 2; the reagent 1 comprises the following components: 1-200mmol/L of an HCY reducing agent, 1.0-100mmol/L of serine, 0.5-0.8g/L of NADH, and 50-200KU/L of LDH; the reagent 2 comprises the following components: 0.1-10g/L of a stabilizing agent, 1-100KU/L of cystathionine beta-synthase, and 1-100KU/L of cystathionine beta-catabolic enzyme. The stable kit for detecting homocysteine has the advantages of convenient determination, fast detection speed, high sensitivity, high accuracy, good stability, wide linear scope and long storage time. The two reagents does not need preparation, are liquid-state reagents, and can be directly used. The kit can be stored below 4 DEG C for at least one year. Furthermore, the raw material cost is low. Clinic examination need is completely satisfied.

The invention provides a homocysteine immune colloidal gold test strip and the preparing method thereof. The test strip is strip shaped which comprises water uptake pad (2), nitrocellulose membrane (NC membrane) (3) with specific coating, capturing line (4) on NC film and quality control line (5), glass fiber colloidal gold combined pad (6) labeled by specific antibody with colloidal gold coating, and sample pad (7), which are subsequently combined on bottom plate (1), the glass fiber colloidal gold combined pad (6) is coated with colloidal gold specific antibody which is S adenosine homocysteine (SAH) monoclonal antibody. The test strip provided by the invention is used to can test homocysteine level in serum, and has the merits of easy operation, fast speed, sensitivity, specificity and so on, with good prospects.

The invention discloses a preparation method and application of a near infrared GSH (glutathione) fluorescent probe. The structural formula of the fluorescent probe is shown as the accompanying drawing. On one hand, the Rhodamine wavelength is increased by 1,3,3-Trimethyl-2-(formylmethylene)indoline, so that the wavelength is prolonged to be 750nm; on the other hand, SH of an analyte and an aldehyde group of the probe take an addition-hydrolysis reaction for realizing GSH, Cys (cysteine) and Hcy(homocysteine) distinguishing. The near infrared GSH fluorescent probe is the first near infrared fluorescent probe which is based on rhodamine derivatives and can efficiently distinguish the GSH, the Cys and the Hcy; the probe shows high sensitivity on the GSH. When the pH value is 6.0 to 8.0, the determination on the GSH by the fluorescent probe is not influenced; the fluorescent probe and the GSH response is fast; the probe cannot be interfered by other biological mercaptan (Cys and Hcy) and other 19 kinds of amino acids; good selectivity is shown. More importantly, the near infrared GSH fluorescent probe can be applied to optical imaging and detection of GSH in cells and tissues.

The invention relates to the field of phosphorescence chemical sensor technology, specifically to a scale phosphorescence chemical sensor for qualitatively detecting cysteine and homocysteine and application thereof, characterized by relating to an iridium complex containing aldehyde group. The aldehyde group of the iridium complex generates cyclization reaction with amido and sulfhydryl of homocysteine and cysteine to convert to heterocycle, aldehyde group and benzene ring contained in original iridium complex conjugate, then conjugation of aldehyde group and benzene ring disappears after reacting with cysteine or homocysteine, thereby affecting spectroscopic properties of the generated products, and detecting cysteine and homocysteine through using the property. The inventive iridium complex solution emits yellow phosphorescence when being excitated by 365 nm ultraviolet light, and emits red phosphorescence reacting with mercaptoamino acid, without being interrupted by other amino acid.

The invention relates to a method for preparing blood samples for detecting homocysteine and/or total folate and is characterized in that the blood sample is brought into contact with (a) at least one reagent for lysis of the blood cells, (b) at lease one inhibitor of the enzymes which produce and break down homocysteine, and optionally (c) at least one acid.

The invention discloses a novel compound capable of being used for distinguishing cysteine/homocysteine and glutathione, particularly relates to a preparation method and application of a novel fluorescent probe, and belongs to the technical field of chemical analysis and detection. A molecular structure is shown as the accompanying drawing. The fluorescent probe is used for fluorescent sensing analysis of cysteine, homocysteine and glutathione in environment or biological samples; through the signal differences of output signals after the action with the probe molecules, the cysteine/homocysteine and glutathione can be well distinguished; the selectivity is high; the anti-interference capability is high; the cysteine, the homocysteine and the glutathione can be sensitively and fast distinguished from various amino acids; good application prospects are realized.

A method and kit is provided for assaying homocysteine in a biological sample containing homocysteine and cysteine. A competing compound with an amino group (—NH₂) is mixed with the biological sample. An aldehyde, e.g. o-phthalaldehyde, is added to the biological sample to form homocysteine complex with fluorescence. The concentration of homocysteine in the biological sample is determined according to the fluorescent intensity.

The invention discloses a method for measuring homocysteine concentration. The method comprises the following steps of: placing a sample to be measured into an enzymatic circular reaction system, performing reaction shown as formulas 1 to 3, measuring and calculating the production rate of ammonia produced in the enzymatic circular reaction system so as to obtain the content of homocysteine in the sample to be measured; and the enzymatic circular reaction system comprises methionine synthase, methionine gama-lyase, O-acetyl homoserine aminocarboxypropyl transferase, 5-methyltetrahydrofolate or salt of the 5-methyltetrahydrofolate, and O-acetyl-L-homoserine. The invention also discloses a corresponding measuring reagent. The invention provides a novel homocysteine enzymological measuring method and a measuring reagent. The method does not need any special instrument, is easy and convenient to operate, has high sensitivity, is low in cost, can realize the clinical, quick and high-flow sample detection, ensures that the homocysteine possibly becomes the clinical conventional detection item, and has high scientific and economic value. The formulas 1 to 3 are shown in the specifications.

This invention relates generally to the field of homocysteine detection. In particular, the invention provides a method for determining homocysteine presence or concentration in samples, which method comprises: contacting a sample containing or suspected of containing Hcy with a Hcy co-substrate and a Hcy converting enzyme in a Hcy conversion reaction to form a Hcy conversion product and a Hcy co-substrate conversion product; and assessing the Hcy co-substrate conversion product to determine the presence, absence and/or amount of the Hcy in the sample. The Hcy co-substrate conversion product may be assessed directly, or it may be assessed by further conversion of the Hcy co-substrate conversion product into another material by the action of one or more additional enzymes. A kit for assaying homocysteine based on the same principle is also provided.

The invention discloses a rapid measurement method for content of homocysteine in a dried blood spot and applies to content measurement of homocysteine in a dried blood spot sample. The method comprises the following steps: obtaining a quantitative standard correction curve of homocysteine; preparing a sample for measurement; performing high-throughput liquid chromatographic separation on homocysteine; detecting homocysteine with tandem mass spectrometry; obtaining content of homocysteine. The method has the advantages of short measurement time, high throughput, high detection sensitivity, high specificity and relatively simple pretreatment process, and has a significance in clinical disease diagnosis and screening.