632results about "Mass spectrometric analysis" patented technology

Provided are methods of detecting the presence or amount of a vitamin D metabolite in a sample using mass spectrometry. The methods generally comprise ionizing a vitamin D metabolite in a sample and detecting the amount of the ion to determine the presence or amount of the vitamin D metabolite in the sample. Also provided are methods to detect the presence or amount of two or more vitamin D metabolites in a single assay.

An apparatus and method analyzes a metabolic profile in a biological sample. The apparatus includes an input unit for inputting the drugs and/or metabolites to be screened; a controlling unit for determining a parameter set for metabolites preparation and for mass spectrometry analysis depending on the input of the kind of metabolites to be screened; a treatment unit for preparing the metabolites to be screened depending on the determined parameter set; a mass spectrometer for performing mass spectrometry analysis on prepared metabolites depending on the parameter set; a database for storing results of analyzing and parameter sets for metabolite preparation and for mass spectrometry analyses; and an evaluation unit for evaluating the results of mass spectrometry by use of reference results stored in the database to output an analysis of the metabolites profile.

Provided herein are methods for developing selected reaction monitoring mass spectrometry (LC-SRM-MS) assays.

The present invention relates to a method of detecting antibiotic resistant bacteria in a sample. The method includes the steps of analyzing a sample derived from bacteria via mass spectrometry to produce a data set, and determining from the data set the presence or absence of a covalently modified antibiotic compound in the sample, wherein the presence of a covalently modified antibiotic compound in the sample is indicative that the bacteria are resistant to the antibiotic. The present invention also relates to a kit for determining the presence or absence of antibiotic resistant bacteria in a sample. The kit includes reagents for preparing and performing the assay, and instructions for the set-up, performance, monitoring, and interpretation of the assay.

The invention provides a method detecting and quantifying proteins by mass spectrophotometric analysis using peptide internal standards and provides a highly sensitive way of detecting protein modifications. In one aspect, the invention provides a method for determining a site of ubiquitination in a polypeptide and for evaluating ubiquitination targets in a population of polypeptides. In this way, a proteome ubiquitination map can be obtained which comprises information relating to the ubiquitination states of a plurality of cellular polypeptides. Maps can be obtained for a variety of different types of cells and cell states. For example, ubiquitination targets in normal and diseased cells can be evaluated. Preferably, the map is stored as data files in a database. Individual ubiquitinated polypeptides identified can be used to generate molecular probes diagnostic of a cell state and/or can serve as targets for agents that modulate one or more cellular processes.

A dual-stage method is provided for identifying a microbe by, for example, its species or its subspecies. The method includes measuring a mass spectrum of the microbe using a mass spectrometer, calculating indicators for similarities between reference mass spectra in a library and the measured mass spectrum, selecting a group of reference mass spectra similar to the measured mass spectrum, determining a distinguishing weight for each mass signal of the reference mass spectra in the group, where the distinguishing weights emphasize differences between the reference mass spectra in the group, and calculating indicators for similarities between the reference mass spectra in the group and the measured mass spectrum as a function of the distinguishing weights.

The present invention provides a method for the analysis of a compound with amino group (e.g., an amino acid or peptide) contained in a sample and convenient manner with a high sensitivity. The compound with amino group in a sample containing the compound with amino group is labeled with a specific carbamate compound such as p-trimethylammonium anilyl-N-hydroxysuccinimidyl carbamate iodide to enhance the selectivity and sensitivity. The present invention is preferably used in conjunction with mass spectrometry such as MS/MS method to facilitate quantitative analysis. The present invention further provides labeling reagents for mass spectrometry.

Method and devices are provided for assessing tissue samples from a plurality of tissue sites in a subject using molecular analysis. In certain aspects, devices of the embodiments allow for the collection of liquid tissue samples and delivery of the samples for mass spectrometry analysis.

A method and system for predicting in advance of treatment whether a cancer patient is likely, or not likely, to obtain benefit from administration of a yeast-based immune response generating therapy, which may be yeast-based immunotherapy for mutated Ras-based cancer, alone or in combination with another anti-cancer therapy. The method uses mass spectrometry of a blood-derived patient sample and a computer configured as a classifier using a training set of class-labeled spectra from other cancer patients that either benefitted or did not benefit from an immune response generating therapy alone or in combination with another anti-cancer therapy. Also disclosed are methods of treatment of a cancer patient, comprising administering a yeast-based immune response generating therapy, which may be yeast-based immunotherapy for mutated Ras-based cancer, to a patient selected by a test in accordance with predictive mass spectral methods disclosed herein, in which the class label for the spectra indicates the patient is likely to benefit from the yeast-based immunotherapy.

A computer-based method for determining a prediction of risk and/or an indication of extent of coronary stenosis in a human subject, comprises the steps of: (a) inputting the level of at least one cholesteryl ester measured in a blood sample collected from said subject; and then (b) inputting the age and gender of said subject; and then (c) generating in said computer from said cholesteryl ester level input, said age input and said gender input a prediction of risk and/or an indication of extent of coronary stenosis blood sample by mass spectrometry.

Adaptive immune responses rely on the ability of cytotoxic T cells to identify and eliminate cells displaying disease-specific antigens on human leukocyte antigen (HLA) class I molecules. Investigations into antigen processing and display have immense implications in human health, disease and therapy. To extend understanding of the rules governing antigen processing and presentation, immunopurified peptides from B cells, each expressing a single HLA class I allele, were profiled using accurate mass, high-resolution liquid chromatography-mass spectrometry (LC-MS/MS). A resource dataset containing thousands of peptides bound to 28 distinct class I HLA-A, -B, and -C alleles was generated by implementing a novel allele-specific database search strategy. Applicants discovered new binding motifs, established the role of gene expression in peptide presentation and improved prediction of HLA-peptide binding by using these data to train machine-learning models. These streamlined experimental and analytic workflows enable direct identification and analysis of endogenously processed and presented antigens.

Methods are described for determining the amount of insulin in a sample. Provided herein are mass spectrometric methods for detecting and quantifying insulin and C-peptide in a biological sample utilizing enrichment and/or purification methods coupled with tandem mass spectrometric or high resolution/high accuracy mass spectrometric techniques. Also provided herein are mass spectrometric methods for detecting and quantifying insulin and b-chain in a biological sample utilizing enrichment and/or purification methods coupled with tandem mass spectrometric or high resolution/high accuracy mass spectrometric techniques.

Described herein are mass spectrometry systems and methods which improve the accuracy of isobaric tag-based quantification by alleviating the pervasive problem of precursor interference and co-isolation of impurities through gas-phase purification. During the gas-phase purification, the mass-to-charge ratios of precursor ions within at least a selected range are selectively changed allowing ions having similar unmodified mass-to-charge ratios to be separated before further isolation, fragmentation or analysis.

The present invention relates to a method for characterizing the antibiotic resistance of a microorganism, said method comprising the steps of (a) providing a reference mass spectrum of an antimicrobial compound, its enzymatic modification product, its molecular target, or of a substrate compound of a its modifying enzyme; (b) exposing a microorganism, a cell lysate thereof, or a growth medium supernatant thereof, to said antimicrobial compound or said substrate compound in aqueous liquid to thereby provide an exposed sample; (c) acquiring a mass spectrum of the exposed sample; (d) comparing the mass spectrum acquired in step c) with the reference mass spectrum of step (a), and (e) determining from said comparison whether modification of said antimicrobial compound, its modification product or its molecular target or of said substrate has occurred following said exposure, and establishing that said microorganism is potentially resistant to said antimicrobial compound when said modification is observed.

Provided are genetic material and nucleic acid sequences useful of increasing yield, biomass, growth rate, vigor, nitrogen use efficiency and/or abiotic stress tolerance, preferably tolerance to nutrient deficiency of a plant. Specifically, the improvement of nitrogen fixation properties in cultivated plants is described.

The disclosure relates to an in vitro technology of detecting presence of a plaque particle, isolating the plaque particle followed by its composition analysis in several diseases states or before the disease sets in. A mechanism and a process leading to plaque formation, identifying a component in the mechanism of plaque formation, an identification of a biomarker for diagnosis/early diagnosis of plaque associated disease is described. A method of screening a candidate agent as an anti-plaque agent using flow cytometer, mass spectrometer and specific biomarkers is performed. Provided also are kits for use in practicing embodiment of the methods. A plaqueproteome database is also generated with novel protein sequences for diagnosis and specific antibodies for specific proteins are also disclosed.

The invention relates to the detection of methylmalonic acid (MMA). In a particular aspect, the invention relates to methods for detecting derivatized methylmalonic acid (MMA) by mass spectrometry.

A method of using a bioactive lysophospholipid (LL) as a biomarker for detecting the presence and recurrence of ovarian cancer. Subspecies of LL, such as lysophosphatidic acid (LPA), lysophosphatidylinositol (LPI), lysophosphatidylcholine (LPC), and lysosphingolipid sphinsosine-1-phosphate (S1P), are used alone or in conjunction to increase the specificity and sensitivity of the assay.

The invention relates to the detection of specified, flagellated bacteria, particularly Salmonella, in food and stool. A single culturing period of about 12 to 24 hours in a liquid nutrient medium without agitation is combined with a position-selective sampling of the flagellated microbes from the liquid of the culture, after which a mass spectrometric detection method is used which recognizes the target bacteria in mixtures. A second culture step is only necessary in exceptional cases. A species-selective or genus-selective culture medium is advantageous. Positional selection becomes possible because these bacteria use their flagella to counteract sedimentation by chemotaxis, and they collect near the surface. This provides a low-cost detection method that is several days faster than conventional methods