The present invention provides systems, devices, and methods for point-of-care and/or distributed testing services. The methods and devices of the invention are directed toward automatic detection of analytes in a bodily fluid. The components of the device can be modified to allow for more flexible and robust use with the disclosed methods for a variety of medical, laboratory, and other applications. The systems, devices, and methods of the present invention can allow for effective use of samples by improved sample preparation and analysis.

Provided are methods of detecting the presence or amount of a dihydroxyvitamin D metabolite in a sample using mass spectrometry. The methods generally comprise ionizing a dihydorxyvitamin 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. In certain preferred embodiments the methods include immunopurifying the dihydroxyvitamin D metabolites prior to mass spectrometry. Also provided are methods to detect the presence or amount of two or more dihydroxyvitamin D metabolites in a single assay.

Provided are methods of detecting the presence or amount of a dihydroxyvitamin D metabolite in a sample using mass spectrometry. The methods generally comprise ionizing a dihydorxyvitamin 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. In certain preferred embodiments the methods include immunopurifying the dihydroxyvitamin D metabolites prior to mass spectrometry. Also provided are methods to detect the presence or amount of two or more dihydroxyvitamin D metabolites in a single assay.

The invention relates to the detection of non-metabolized vitamin D. In a particular aspect, the invention relates to methods for detecting underivatized non-metabolized vitamin D by mass spectrometry.

The invention relates to the detection of non-metabolized vitamin D. In a particular aspect, the invention relates to methods for detecting underivatized non-metabolized vitamin D by mass spectrometry.

The present invention relates to a method for determining the distinctive nutritional requirements of a patient with specific nutritional needs and providing a composition meeting the distinctive nutritional requirements of said patient.

The present invention relates to a method for determining the distinctive nutritional requirements of a patient with specific nutritional needs and providing a composition meeting the distinctive nutritional requirements of said patient.

Biomarkers of NASH, NAFLD, and fibrosis and methods for diagnosis (or aiding in the diagnosis) of NAFLD, NASH and/or fibrosis are described herein. Additionally, methods of distinguishing between NAFLD and NASH, methods of classifying the stage of fibrosis, methods of determining the severity of liver disease, methods of determining the severity of liver disease or fibrosis, and methods of monitoring progression/regression of NASH, NAFLD, and/or fibrosis are described herein.

Biomarkers of NASH, NAFLD, and fibrosis and methods for diagnosis (or aiding in the diagnosis) of NAFLD, NASH and/or fibrosis are described herein. Additionally, methods of distinguishing between NAFLD and NASH, methods of classifying the stage of fibrosis, methods of determining the severity of liver disease, methods of determining the severity of liver disease or fibrosis, and methods of monitoring progression/regression of NASH, NAFLD, and/or fibrosis are described herein.

The present disclosure provides a compound having Formula (I): or a pharmaceutically acceptable salt of hydrate thereof, wherein R.sup.1, A, m, and n are as described herein, for use in conducting immunodiagnostic assays for accurately measuring concentrations of circulating vitamin D, as well as for thyroxine and related analytes, estrogen and related analytes, and testosterone and related analytes.

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