3069 results about "Blood cell" patented technology

A device and a method to provide a more reliable and accurate measurement of hematocrit (Hct) by noninvasive means. The changes in the intensities of light of multiple wavelengths transmitted through or reflected light from the tissue location are recorded immediately before and after occluding the flow of venous blood from the tissue location with an occlusion device positioned near the tissue location. As the venous return stops and the incoming arterial blood expands the blood vessels, the light intensities measured within a particular band of near-infrared wavelengths decrease in proportion to the volume of hemoglobin in the tissue location; those intensities measured within a separate band of wavelengths in which water absorbs respond to the difference between the water fractions within the blood and the displaced tissue volume. A mathematical algorithm applied to the time-varying intensities yields a quantitative estimate of the absolute concentration of hemoglobin in the blood. To compensate for the effect of the unknown fraction of water in the extravascular tissue on the Hct measurement, the tissue water fraction is determined before the occlusion cycle begins by measuring the diffuse transmittance or reflectance spectra of the tissue at selected wavelengths.

Methods of treating, preventing and / or managing myclodysplastic syndromes are disclosed. Specific methods encompass the administration of an immunomodulatory compound, or a pharmaceutically acceptable salt, solvate, hydrate, stereoisomer, clathrate, or prodrug thereof, alone or in combination with a second active ingredient, and / or the transplantation of blood or cells. Specific second active ingredients are capable of affecting or blood cell production. Pharmaceutical compositions, single unit dosage forms, and kits suitable for use in methods of the invention are also disclosed.

A biosensor that utilizes a mediator, i.e., an isomer of phenanthroline quinone, 1,10-phenanthroline-5,6-dione, and a metal ion, such as manganese, with an enzyme dependent upon NAD(P)+, such as, for example, glucose dehydrogenase, for improving the hematocrit bias and oxygen bias of biosensors. The electrodes of the biosensors employing this mediator and a metal ion provide an accurate clinical response over a hematocrit range that ranges from about 20% to about 70% and over an oxygen tension range that ranges from about 1 kPa to about 20 kPa.

Methods and devices for determining the concentration of an analyte in a physiological sample are provided. In the subject methods, the physiological sample is introduced into an electrochemical cell having a working and reference electrode. A first electric potential is applied to the cell and the resultant cell current over a period of time is measured to determine a first time-current transient. A second electric potential of opposite polarity is then applied and a second a time-current transient is determined. The preliminary concentration of the analyte is then calculated from the first and / or second time-current transient. This preliminary analyte concentration less a background value is then multiplied by a hematocrit correction factor to obtain the analyte concentration in the sample, where the hematocrit correction factor is a function of the preliminary analyte concentration and the variable γ of the electrochemical cell. The subject methods and devices are suited for use in the determination of a wide variety of analytes in a wide variety of samples, and are particularly suited for the determination of analytes in whole blood or derivatives thereof, where an analyte of particular interest is glucose.

There is provided a cholesterol sensor with high-accuracy and excellent response, whose object to be measured is whole blood, where plasma with hemocytes therein filtered can rapidly reach an electrode system. In a biosensor where plasma with hemocytes therein filtered with a filter is sucked into a sample solution supply pathway due to capillarity, there are formed: a first pressing part for holding a primary side portion of the filter from the bottom; a second pressing part for holding a secondary side portion of the filter from the top and the bottom; a third pressing part for holding the central portion of the filter from the top; and a void for surrounding the filter between the second pressing part and third pressing part.

There is provided the reagent layer composition that can substantially reduce the measurement bias arising from hematocrits. The addition of fatty acid (4-20 carbons) and quaternary ammonium salt to a commonly used reagent layer composition composed of an enzyme, an electron transfer mediator, and several water soluble polymers not only reduce the hematocrit level-dependent bias but also provide very stable performance for an extended period of time. Disclosed are also various types of sub microliter sample volume electrochemical biosensors that are suitable to use with the reagent layer composition of present invention.

A blood testing tool is provided, which separates blood cells and can collect blood plasma or blood serum with a high yield. The blood testing tool includes an asymmetric porous membrane with a pore size distribution in which an average pore size varies to be reduced continuously or discontinuously in a thickness direction. The porous membrane includes a blood supply portion, a development portion, and a blood-cell blocking portion formed between the blood supply portion and the development portion and pores in the blood cell blocking portion include only pores through which blood cells cannot pass. When blood is supplied to one side with larger pores of the blood supply portion, the blood moves in a direction parallel to a surface of the porous membrane by a capillary phenomenon, but only blood plasma or blood serum moves into the development portion to develop.

The present invention provides systems useful for the enrichment of analytes, for example, cells of selected types, including but not limited to blood cells, stem cells, and pathogens, in samples. The invention also provides methods for analyzing the condition of a patient based on characteristics identified through analysis of the analytes in case and control samples.