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Affinity Labels definition: Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.
Cross-Linking Reagents definition: Reagents with two reactive groups, usually at opposite ends of the molecule, that are capable of reacting with and thereby forming bridges between side chains of amino acids in proteins; the locations of naturally reactive areas within proteins can thereby be identified; may also be used for other macromolecules, like glycoproteins, nucleic acids, or other.
Indicators and Reagents definition: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
reagent/indicator definition: substance employed to produce a chemical reaction so as to detect, measure, or produce other substances.
Reagent Strips definition: Narrow pieces of material impregnated or covered with a substance used to produce a chemical reaction. The strips are used in detecting, measuring, producing, etc., other substances. (From Dorland, 28th ed)
Reagents definition: Substances intended to detect and/or measure, in some cases producing or modifying other substances, a specific analyte of interest (e.g., enzymes, hormones). Substances used as reagents must be sufficiently pure to appropriately perform a specific analytical test. Reagents are typically used in the clinical laboratory for clinical chemistry, immunochemistry, hematology, microbiology (e.g., culture), infectious immunology, and molecular biology (e.g., nucleic acid technology) tests.
Reagent definition: A chemical that has general laboratory application and that is not labeled or otherwise intended for a specific application. General purpose reagents include cytological preservatives, decalcifying reagents, fixatives and adhesives, tissue processing reagents, isotonic solutions, and pH buffers.
Sulfhydryl Reagents definition: Chemical agents that react with SH groups. This is a chemically diverse group that is used for a variety of purposes. Among these are enzyme inhibition, enzyme reactivation or protection, and labelling.
sulfhydryl reagent definition: compounds which interact with disulfide bonds and sulfhydryl groups in proteins to either favor or inhibit the formation of disulfide crosslinks; usually means a reducing agent which inhibits disulfide formation.
Reagents, Immunoassay, Protein, Alpha-1-Antitrypsin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids (e.g., serum) to determine the presence of protein alpha-1 Antitrypsin (AAT), also known as protease inhibitor. AAT is a plasma protein that acts as the major inhibitor of trypsin and other proteolytic enzymes. Its concentration rises significantly during acute inflammatory processes (i.e., it is an acute-phase reactant), including surgery, myocardial infarction, infections, and/or in the presence of tumors. Increased levels of AAT typically occur within 24 hours of the injury and decrease in 4 or 5 days. Reduced levels or the absence of AAT is associated with increased risk of emphysema, especially in children.
Reagents, Immunoassay, Protein, Alpha-2-Macroglobulin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids (typically plasma) to determine the protein alpha-2 macroglobulin (A2MG), a high-molecular-weight protein whose major function is maintaining oncotic pressure during protein loss and that inhibits protease in a different way than other inhibitors. A2MG inhibits a wide variety of enzymes, including trypsin, plasmin, thrombin, and elastase. Increased levels of A2MG in blood (hyperglobulinemia) are seen in nephrotic syndrome.
Reagents, Immunoassay, Lipoprotein, Apolipoprotein definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids (typically serum) to determine one or several of a group of proteins (apolipoproteins) usually synthesized in the liver and/or intestines. Apolipoproteins are usually found surrounding polar lipids (phospholipids and cholesterol) forming a group of lipid-protein complexes in which lipids are transported in the blood. Apolipoproteins have been labeled and described in five major groups from A to E according to their functions.
Reagents, Chromatography definition: Reagents used in assays to separate mixtures of chemical compounds into individual components according to the different rates at which they are retarded by a stationary material (stationary phase) as they pass over it. These reagents include a solvent mixture (i.e., the mobile phase, a gas or liquid) that carries the sample, the adsorbing material (a thin layer or a column), and other auxiliary reagents (e.g., solvents for elution). Chromatography reagents are mostly used in the clinical laboratory to identify trace quantities of substances in body fluids.
Reagents, Hematology, Coagulation definition: Hematology reagents used in tests of the sequential process by which the multiple factors of the blood interact in a blood sample, resulting in the formation of an insoluble fibrin clot (coagulation).
Reagents, Cytology/Histology definition: Reagents used in qualitative and/or quantitative analyses of human cells and tissues, particularly their structure, function, and pathology. These reagents include those used for staining, cleaning, fixing, control, and calibration; they also include the appropriate media needed to perform cytology and/or histology procedures. Frequently, these reagents are available in kits that include all the necessary reagents for a particular test.
Reagents, Immunoassay, Anemia Test, Ferritin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (typically serum) to determine the level of ferritin, an iron-apoferritin complex, one of the main forms of iron storage in the body. Ferritin is present in the blood in very low concentrations, but it usually reflects the variation in the total iron body stores. Decreased levels of ferritin are found very early in the development of iron deficiency in otherwise healthy patients; increased levels of ferritin are associated with chronic infections, rheumatoid arthritis, renal diseases, a variety of malignancies , viral hepatitis, and other diseases.
Reagents, Immunoassay, Protein, Transport, Haptoglobin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids to determine haptoglobin (HAP), a plasma glycoprotein that irreversibly binds to free hemoglobin. The hemoglobin/haptoglobin complex is removed by the parenchymal cells of the liver, preventing loss of hemoglobin and conserving iron. Haptoglobin is one of the acute-phase reactants. Increased levels of HAP in plasma occur in extensive tissue damage and necrosis; low levels are associated with hemolytic anemia, transfusion reactions, and malaria.
Reagents, Hematology definition: Reagents intended to perform qualitative and/or quantitative analyses of the morphology of the blood, its components, and blood-forming tissues. These reagents include those used for blood cell counts, coagulation testing, other hematology tests, control, and calibration.
Reagents, Immunoassay, Protein, Transport, Hemopexin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample to determine hemopexin, a plasma glycoprotein that irreversibly binds to free heme (a product of the breakdown of hemoglobin into heme and globin); the combined product is removed by the liver. Decreased levels of hemopexin are found in plasma after hemolysis; as hemopexin is not a protein that reflects acute inflammation (i.e., it is not an acute-phase reactant). Its periodic determination is a better indicator of hemolysis when acute inflammation and hemolysis are concurrent.
Reagents, Serology, Virus, Hepatitis Be definition: Serology reagents used to detect in a patient's sample either soluble antigens closely associated to surface antigens of hepatitis B or antibodies to those soluble antigens. These soluble antigens are known as Be (or early) antigens
Reagents, Immunoassay, Protein, Immunoglobulin A definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids (typically serum) to determine immunoglobulin A (IgA), approximately 10% to 15% of total immunoglobulin in normal serum. IgA is also found as secretory IgA (it includes two molecules of IgA) in tears, saliva, milk, and sweat. Increased levels of IgA in serum are associated with respiratory, renal, and skin infections.
Reagents, Immunohematology definition: Reagents intended for use in antigen-antibody reactions performed for red blood cell grouping (typing), antibody detection and identification, and cross-matching of donor and recipient prior to blood component transfusion (known as compatibility testing). These reagents are also intended for use in antigen-antibody reactions performed during evaluations of adverse reactions to blood component transfusion and red blood cell autoimmunity (e.g., autoimmune hemolytic anemia, hemolytic disease of the newborn).
Reagents, Microbiology definition: Reagents used in biochemical assays for laboratory (in vitro) cultivation and identification of microorganisms; some reagents are used to determine the susceptibility of microorganisms to antimicrobial agents. Microbiology reagents include culture media, stains, buffers, antibiotics, calibrators, controls, and standards. Most tests are based on biochemical identification (e.g., agglutination procedures, with detection either directly or using fluorescent techniques).
Reagents, Immunoassay, Cardiac Marker, Protein, Myoglobin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of a sample of body fluids (e.g. serum, urine) to determine myoglobin, an oxygen binding protein found in small amounts in cardiac and skeletal muscle. The level of liberated myoglobin increases, both in blood and in urine, soon after the occurrence of heart damage (e.g., as the result of myocardial infarction) and before the increase of creatine kinase activity, permitting its use as an early cardiac marker. Myoglobin levels also increase due to injuries in skeletal muscles and/or after vigorous physical exercise.
Reagents, Hematology, Fibrinolysis, Plasminogen definition: Hematology reagents intended to perform qualitative and/or quantitative analyses on a sample of body fluids (typically plasma) to determine plasminogen, a beta globulin that is one of the components of the fibrinolytic enzyme system in blood. Plasminogen levels are decreased in several diseases including intravascular coagulation, fibrinogenolysis, and severe liver diseases; congenital abnormalities are rare.
Reagents, Immunoassay, Thyroid Hormone, Thyroglobulin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of a sample of body fluids (typically serum) to determine thyroglobulin (Tg), a large glycoprotein (a prohormone) that is stored in the follicular colloid of the thyroid gland and participates in the synthesis of triiodothyronine (T3) and thyroxin (T4). Increased levels of Tg are associated to thyroid papillary and follicular carcinomas, thyroid adenoma, and other diseases of the thyroid; its determination is particularly useful in monitoring recurrence of thyroid carcinoma following surgical resection. Determining the level of thyroglobulin in serum samples is difficult if antithyroglobulin antibodies are present, as frequently occurs in thyroid cancer patients.
Reagents, Immunoassay, Protein, Transport, Transferrin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of body fluids to determine transferrin (also known as siderophilin), a beta-globulin protein that is the main plasma protein that binds and transports iron. Transferrin (TRF) is also capable of binding other metals, such as copper, calcium, zinc, and cobalt. The level and degree of iron saturation of TRF is used as a differential diagnosis in anemia. High transferrin levels are associated with pregnancy or estrogen administration; low levels of TRF are found in the inherited disease atransferinemia, as well as in malnutrition, inflammation, and malignancies.
PROSTATE-SPECIFIC ANTIGEN (PSA) FOR MANAGEMENT OF PROSTATE CANCERS definition: A tumor-associated antigen immunological test system is a device that consists of reagents used to qualitatively or quantitatively measure, by immunochemical techniques, tumor-associated antigens in serum, plasma, urine, or other body fluids.
Reagents, Immunoassay, Tumor Marker, Enzyme, Prostate Specific Antigen definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of a sample of body fluids (e.g., serum) to determine the prostate-specific-antigen (PSA) enzyme, either total or free (fPSA); these reagents include antibodies (typically monoclonal antibodies) with the capability of binding to this tumor marker. PSA level is used to monitor treatment of prostate carcinoma because it correlates with the stages of tumor extension and metastasis; the level of total and/or free PSA and the proportion of free to total PSA are also used in diagnosis of prostate carcinoma and its differentiation from benign prostatic hyperplasia.
REAGENTS, CYSTICERCOSIS definition: Echinococcus spp. serological reagents are devices that consist of Echinococcus spp. antigens and antisera used in serological tests to identify antibodies to Echinococcus spp. in serum. The identification aids in the diagnosis of echinococcosis, caused by parasitic tapeworms belonging to the genus Echinococcus and provides epidemiological information on this disease. Echinococcosis is characterized by the development of cysts in the liver, lung, kidneys, and other organs formed by the larva of the infecting organisms.
Reagents, Clinical Chemistry, Enzyme, 5'-Nucleotidase definition: Clinical chemistry reagents intended to perform qualitative and/or quantitative chemical analyses of body fluids (typically serum) to determine the level of the enzyme 5'ribonucleotide phosphohydrolase (abbreviated as 5'NT or NTP). NTP activity is increased two- to sixfold in hepatobiliary diseases in which there is interference with the secretion of bile, as occurs when the bile duct is obstructed by stones or tumors or with biliary cirrhosis.
Reagents, Clinical Chemistry, Enzyme, Alanine Transferase definition: Clinical chemistry reagents intended to perform qualitative and/or quantitative chemical analyses of body fluids (typically serum) to determine the level of the enzyme alanine transferase (ALT), also known as alanine aminotransferase. ALT in serum is typically increased in liver diseases associated with hepatic necrosis, such as viral hepatitis and infectious mononucleosis with involvement of the liver.
Reagents, Clinical Chemistry, Enzyme, Aldolase definition: Clinical chemistry reagents intended to perform qualitative and/or quantitative chemical analyses of body fluids (typically serum) to determine the level of the enzyme aldolase (ALD). Aldolase in serum increases in a variety of diseases, but the assays are mostly performed to determine primary diseases of skeletal muscle (e.g., Duchenne muscular dystrophy).
Reagents, Clinical Chemistry, Enzyme, Lysosyme definition: Clinical chemistry reagents intended to perform qualitative and/or quantitative chemical analyses of body fluids (typically serum) to determine the level of the enzyme lysosyme (also known as muramidase and mucopeptide glycohydrolase). The level of lysosyme in serum is increased in several diseases, including monomyelocytic leukemia and granulomatous inflammation.
Reagents, Electrophoresis definition: Reagents used in assays to separate ionic solutes based on differences in their rates of migration in a liquid medium under the influence of an electric field (i.e., electrophoresis assays). These reagents typically include a porous supporting medium (e.g., agarose gel film, cellulose acetate sheet), buffers, stains, and other auxiliary reagents. Electrophoresis assays are mostly used in clinical laboratories to separate proteins and lipoproteins in body fluids such as serum, urine, and cerebrospinal fluid; these assays are also used to separate proteins in tissues and erythrocites.
Reagents, Immunoassay definition: Reagents intended for use in a diverse range of sensitive and specific clinical assays using immunochemical reactions (immunoassays). The specificity and high affinity of antibodies for specific antigens, coupled with the ability of antibodies to cross-link antigens, allows the identification and quantification of specific substances using a variety of methods. Some of these reagents are available in kits that include an antibody or antigen, calibrators, and other specific reagents (e.g., activator). Immunoassay reagents may be specific for one or many different types of assays, such as electrophoresis, nephelometry, or microtiter assays. They are used in a variety of tests to determine levels of proteins, hormones, drugs of abuse, and many other substances, facilitating the diagnosis of allergies, autoimmune diseases, tumors, and other conditions.
Reagents, Immunoassay, Renal Metabolism, Aldosterone definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses of a sample of body fluids (e.g., serum, urine) to determine the level of aldosterone, the major mineralocorticoid hormone secreted by the adrenal cortex; its secretion is stimulated by angiotensin II. Very high levels of aldosterone (i.e., aldosteronism) are associated with plasma volume expansion, hypertension, and edema; they may occur due to overproduction of aldosterone (e.g., adrenal adenoma) or secondary due to extra adrenal diseases such as nephrotic syndrome or congestive heart failure.
Reagents, Immunoassay, Vitamin, D Metabolite, 1,25-Dihydroxyvitamin D definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (e.g., serum) to determine 1,25-dihydroxyvitamin D, also known as 1,25-(OH)2-D, a metabolite of both vitamin D2 and D3. These assays are not designed to differentiate between D2 and D3 metabolites. Decreased levels of this metabolite are associated with renal failure, hypercalcemia, or malignancy and other diseases.
Reagents, Immunoassay, Vitamin, D Metabolite, 25-Hydroxyvitamin D definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (e.g., serum) to determine 25-hydroxyvitamin D (25-OH-D), a metabolite of both vitamin D2 and D3. These assays are not designed to differentiate between D2 and D3 metabolites; a large number of bone and mineral metabolism disorders are associated with abnormal levels of 25-OH-D, including hypocalcaemia and osteomalacia
Reagents, Serology definition: Reagents used in tests (i.e., serologic tests) to measure serum antibody titers, antigens, or toxins due to pathogenic microorganisms (e.g., bacteria, viruses, parasites) through in vitro reactions of immune sera (e.g., agglutination, complement fixation, precipitin).
Reagents, Clinical Chemistry, Nitrogen Metabolite, Blood Urea Nitrogen definition: Clinical chemistry reagents intended to perform qualitative and/or quantitative chemical analysis of body fluids (typically blood or serum) to determine the level of urea in blood, usually referred to as blood urea nitrogen (BUN). An increase in BUN is referred as azotemia, typically caused by renal failure.
Reagents, Immunohematology, Blood Grouping, ABO Typing definition: Immunohematology reagents used to characterize human blood in types A, B, AB, or O. There are two types of tests for ABO grouping: The forward grouping test in which cells from a person of an unknown group are reacted with known anti-A and anti-B sera and the reverse test (confirmatory) that involves testing the reaction of serum of the unknown type with cells of known A and B reactivity.
Reagents, Immunoassay, Fertility Hormone, 17-Hydroxyprogesterone definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (e.g., serum saliva, whole blood) to determine 17-hydroxyprogesterone, a precursor of cortisol and aldosterone. Determination of the levels of 17-hydroxyprogesterone are useful in the evaluation of women with infertility and/or excessive growth of terminal hair (hirsutism). Measurements in plasma are also used for the diagnosis and monitoring of therapy of congenital adrenal hyperplasia (CAH) in newborns.
Reagents, Immunoassay, Control, Allergy definition: Reagents consisting of substances of known concentrations that are assayed by the usual clinical laboratory methods and that resemble the unknown specimen; they are used for quality control of immunoassay tests performed for the determination of one or more in a group of immunoglobulin E (IgE) proteins or histamines released by mast cells when an antigen (allergen) cross-links two attached IgE molecules. These reagents may be either specific for quality control of an allergy-related substance or, more frequently, appropriate for control of a whole set of similar allergy-related substances.
Reagents, Immunocytochemistry definition: Reagents that include labeled antibody substances intended for use as specific probes for protein and peptide antigens. These reagents permit the examination of single cells for specific markers to identify cell lines and/or to determine the cells synthetic capability. Labels may be either fluorescent or enzymatic; enzymatic labels make possible the test of fixed tissues embedded in paraffin. Light microscopy is usually employed to identify labeled features, but electron microscopy is also used in some methods. Immunocytochemistry reagents are widely used to determine substances (e.g., proteins) present in various tissue samples (e.g., frozen tissue, paraffin-embedded tissue, fine-needle aspirations), especially in neoplastic tumor cells.
Reagents, Immunoassay, Protein, Alpha-1-Microglobulin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (e.g., plasma, serum, urine, amniotic fluid) to determine the protein alpha-1-microglobulin (A1MG), a low-molecular-weight protein. Increased ratios of alpha-1-microglobulin/creatinine in urine are associated with kidney tubule and/or glomerular damage, especially in children. High levels of placental A1MG in the serum of pregnant woman may be considered an indicator of intrauterine diseases (e.g., intrauterine hypoxia).
Reagents, Immunoassay, Endocrine Hormone, Adrenocorticotropin definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (typically serum) to determine the endocrine hormone adrenocorticotropin (ACTH), also known as corticotropin. ACTH is secreted by the anterior lobe of the pituitary gland. Its concentration in plasma is usually very low following a circadian rhythm. Increased concentrations of ACTH are found in diseases such as congenital adrenal hyperplasia, Addison's disease, ACTH-secreting tumors, and hypoglycemia. Determination of the ACTH level is also useful in differentiating primary from secondary adrenal insufficiency.
Reagents, Immunoassay, Endocrine Hormone, Catecholamine, Epinephrine definition: Immunoassay reagents intended to perform qualitative and/or quantitative analyses on a body fluid sample (typically serum or urine) to determine epinephrine (also known as adrenaline), a secondary amine hormone in the catecholamine group. Epinephrine is the major substance produced by the adrenal medulla, it is a potent stimulator of the nervous system and a powerful cardiac stimulant; epinephrine also influences metabolic processes. Increased epinephrine levels (most assays measure active, free epinephrine) are associated with thyroid hormone deficiency, low blood pressure, congestive heart failure, and arrhythmias. Measurements of epinephrine and its metabolites (e.g., urinary metanephrines, vanillylmandelic acid) are also used for diagnosis of some catecholamine- secreting tumors (e.g., pheochromocytoma).
Reagents, Immunoassay, Calibration, Allergy definition: Reagents intended to establish points of reference (i.e., calibrate) in immunoassay tests performed to determine either immunoglobulin E (IgE) or histamines released by mast cells when an antigen (allergen) cross-links two attached IgE molecules. These reagents may either be specific for calibration of an allergy-related substance or more frequently appropriate to calibrate a whole set of similar allergy-related substances.
PHARMACEUTICAL AIDS/REAGENTS definition: NOTE: Includes agents used in the preparation or reconstitution of pharmaceutical products. Includes diluents with separate NDC codes.
Reagents, Skin Test, Allergy definition: Reagents used in tests performed on the skin to identify substances that produce an allergic reaction in a patient (i.e., allergens). Typically, a small amount of the suspected allergy substance (i.e., the allergen or "test reagent") is placed on the skin (usually on the forearm or back) and introduced under the skin by scratching or pricking the skin with a sterile needle. The skin is observed for about 20 minutes; the test is considered positive (probable allergy) if redness or, more importantly, swelling is present. These reagents may be also injected under the skin (intracutaneous), using a small syringe, or applied to the skin, usually mixed with a nonallergenic material in aluminum discs that are typically placed on the upper back and covered with tape for longer periods (typically 48 hours) to determine allergic contact dermatitis (i.e., patch testing). Skin test reagents are used mainly to determine specific substances that cause respiratory (e.g., dust, pollen) and food (e.g., seafood) allergies, but they are also used to test for allergies to drugs (e.g., penicillin) or to products (e.g., latex).