The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform

H. Bloy - One of the best experts on this subject based on the ideXlab platform.

Shozo Yamamoto - One of the best experts on this subject based on the ideXlab platform.

  • Enzyme Immunoassay of human plasma 11-dehydrothromboxane B2.
    Thrombosis research, 1991
    Co-Authors: Wataru Takasaki, Yoko Hayashi, Akihiko Nakagawa, Yorihisa Tanaka, Kan-ichi Nakamura, Hideyo Shindo, Shozo Yamamoto
    Abstract:

    Abstract 11-Dehydrothromboxane B2 (11-dhTXB2) is a proposed marker compound for thromboxane A2 formed in vivo. An Enzyme Immunoassay was established for determination of the plasma concentration of this compound. The assay was based on a horseradish peroxidase-linked Immunoassay utilizing polyclonal anti-11-dhTXB2 antibody obtained from a rabbit, and enabled determination of 11-dhTXB2 in the range of 2 to 500 pg/tube with an IC50 of 36 pg. The cross-reactivities with TXB2, 2,3-dinor-TXB2 and other prostanoids were less than 0.05%. Validity of the Enzyme Immunoassay was confirmed by a radioImmunoassay utilizing a monoclonal antibody. The plasma 11-dhTXB2 was immunoaffinity-purified by one step using an immobilized monoclonal antibody. The mean plasma level of 11-dhTXB2 in six male volunteers was 4.0 ± 0.3 pg/ml by this Enzyme Immunoassay.

Sheryl L.g. Johnston - One of the best experts on this subject based on the ideXlab platform.

Thomas C Havighurst - One of the best experts on this subject based on the ideXlab platform.

  • autoantibody testing for connective tissue diseases comparison of immunodiffusion immunoblot and Enzyme Immunoassay
    American Journal of Clinical Pathology, 1997
    Co-Authors: Alan J. Bridges, Timothy E Lorden, Thomas C Havighurst
    Abstract:

    We evaluated 500 consecutive patient serum samples for the presence of six autoantibodies by three antibody detection methods: immunodiffusion, immunoblot, and Enzyme Immunoassay. Clinical data were reviewed for each patient with positive antibody test results. Serum samples from 60 patients revealed antibodies to Sm, ribonucleoprotein (RNP), SSA/Ro, SSB/La, Scl-70, or Jo-1. There were 7 false-positive test results (1%). All three methods detected autoantibodies in 36 (68%) of 53 patients with connective tissue disease. Immunoblot was the most sensitive method to detect autoantibodies (92%). Enzyme Immunoassay and immunodiffusion were less sensitive (81% and 74%, respectively). Antiribonucleoprotein and anti-SSB/La antibodies were more often detected by immunoblotting, whereas anti-SSA/Ro antibodies were more often detected by Enzyme Immunoassay. Newer antibody detection methods (immunoblot and Enzyme Immunoassay) are less time consuming than immunodiffusion and show good interassay sensitivity without loss of specificity. A combination of immunoblot and Enzyme Immunoassay yielded excellent assay sensitivity (100%) and specificity (99%) for detection of autoantibodies.

Eiji Ishikawa - One of the best experts on this subject based on the ideXlab platform.

  • Novel and Sensitive Noncompetitive Enzyme Immunoassay (Hetero-Two-Site Enzyme Immunoassay) for Arginine Vasopressin
    Analytical Letters, 1991
    Co-Authors: Seiichi Hashida, Koichiro Tanaka, Naoko Yamamoto, Takeshi Uno, Ken'ichi Yamaguchi, Eiji Ishikawa
    Abstract:

    Abstract A novel and sensitive noncompetitive Enzyme Immunoassay (hetero-two-site Enzyme Immunoassay) for arginine vasopressin in plasma is described. Plasma (0.3 ml) was diluted 1.3-fold with an appropriate buffer and filtered by centrifugation in a micro-concentrator with polysaccharide membrane to eliminate plasma proteins. Arginine vasopressin in plasma filtrates was biotinylated and trapped onto anti-arginine vasopressin IgG-coated polystyrene balls. After washing the polystyrene balls to eliminate other biotinylated substances, the biotinylated arginine vasopressin was eluted from the polystyrene balls with HCl and was reacted with anti-arginine vasopressin Fab′-peroxidase conjugate. The complex formed was trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorometry. The detection limit of arginine vasopressin was 11 fg (10 amol)/tube. This was 45-fold lower than that by competitive Enzyme Immunoassay using the same antiserum as us...

  • Novel and sensitive noncompetitive Enzyme Immunoassay (hetero‐two‐site Enzyme Immunoassay) for α‐human atrial natriuretic peptide in plasma
    Journal of clinical laboratory analysis, 1991
    Co-Authors: Seiichi Hashida, Naoko Yamamoto, Eiji Ishikawa
    Abstract:

    A novel and sensitive noncompetitive Enzyme Immunoassay (hetero-two-site Enzyme Immunoassay) for alpha-human atrial natriuretic peptide (alpha-hANP) in plasma, which uses only one monoclonal IgG for the ring structure of alpha-hANP, is described. Plasma was filtered through polysaccharide membrane to separate peptides from proteins. The plasma filtrate was incubated with N-hydroxysuccinimidobiotin to biotinylate alpha-hANP and subsequently with a polystyrene ball coated with monoclonal IgG for the ring structure of alpha-hANP to trap biotinylated alpha-hANP. The polystyrene ball was washed to eliminate unreacted N-hydroxysuccinimidobiotin and other biotinylated substances, and biotinylated alpha-hANP was eluted from the polystyrene ball with HCl. The eluate was neutralized and incubated with horseradish peroxidase-labeled antibody IgG for the ring structure of alpha-hANP and subsequently with two streptavidin-coated polystyrene balls. Peroxidase activity bound to the streptavidin-coated polystyrene balls was assayed by fluorometry. The detection limit of alpha-hANP was 20 amol, and the assay range of plasma alpha-hANP was 0.8-1,200 ng/L using 100 microliters of plasma filtrates corresponding to 75 microliters of plasma. Plasma levels of hANP in healthy subjects were 9.8-21.5 ng/L. These values were significantly lower than those measured by a two-site Enzyme Immunoassay probably due to the presence of alpha-hANPs lacking some N-terminal amino acids, which were as reactive as alpha-hANP in the two-site Enzyme Immunoassay but less reactive in the hetero-two-site Enzyme Immunoassay.

  • Novel and sensitive noncompetitive Enzyme Immunoassay (hetero-two-site Enzyme Immunoassay) for α-human atrial natriuretic peptide in plasma
    Journal of Clinical Laboratory Analysis, 1991
    Co-Authors: Seiichi Hashida, Naoko Yamamoto, Eiji Ishikawa
    Abstract:

    A novel and sensitive noncompetitive Enzyme Immunoassay (hetero-two-site Enzyme Immunoassay) for α-human atrial natriuretic peptide (α-hANP) in plasma, which uses only one monoclonal IgG for the ring structure of α-hANP, is described. Plasma was filtered through polysaccharide membrane to separate peptides from proteins. The plasma filtrate was incubated with N-hydroxysuccini-midobiotin to biotinylate α-hANP and subsequently with a polystyrene ball coated with monoclonal IgG for the ring structure of α-hANP to trap biotinylated α-hANP. The polystyrene ball was washed to eliminate unreacted N-hydroxysuccinimidobiotin and other biotinylated substances, and biotinylated α-hANP was eluted from the polystyrene ball with HCI. The eluate was neutralized and incubated with horseradish peroxidase-labeled antibody IgG for the ring structure of α-hANP and subsequently with two streptavidin-coated polystyrene balls. Peroxidase activity bound to the streptavidin-coated polystyrene balls was assayed by fluorometry. The detection limit of α-hANP was 20 amol, and the assay range of plasma α-hANP was 0.8–1,200 ng/L using 100 μl of plasma filtrates corresponding to 75 μl of plasma. Plasma levels of hANP in healthy subjects were 9.8–21.5 ng/L. These values were significantly lower than those measured by a two-site Enzyme Immunoassay probably due to the presence of α-hANPs lacking some N-terminal amino acids, which were as reactive as α-hANP [1–28] in the two-site Enzyme Immunoassay but less reactive in the hetero-two-site Enzyme Immunoassay.