Patents by Inventor Berend Houwen

Berend Houwen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6911313
    Abstract: A method for discriminating and counting erythroblasts comprises the steps of: (i) staining leukocytes in a hematologic sample by adding a fluorescent labeled antibody capable of binding specifically with leukocytes to the hematologic sample; (ii) raising the permeability only of cell membranes of erythroblasts in the hematologic sample to a nucleotide fluorescent dye which does not permeate a cell membrane usually, the nucleotide fluorescent dye having a fluorescent spectrum capable of being distinguished from that of a fluorescent labeling compound of the fluorescent labeled antibody in step (i); (iii) staining nuclei of the erythroblasts in the hematologic sample with the nucleotide fluorescent dye; (iv) subjecting the hematologic sample to flowcytometry to detect at least two fluorescent signals from each cell; and (v) discriminating and counting the erythroblasts from difference in intensity between the at least two fluorescent signals.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: June 28, 2005
    Assignee: Sysmex Corporation
    Inventors: Berend Houwen, Fu-sheng Wang, Tomohiro Tsuji, Takashi Sakata, Yukio Hamaguchi
  • Patent number: 6900023
    Abstract: A method for classifying and counting leukocytes comprises the steps of: (1) adding to a hematological sample the following fluorescence-labeled antibodies labeled with fluorescent dyes which emit fluorescences distinguishable from each other; (a) a first fluorescence-labeled antibody (1st antibody) which bonds specifically to leukocytes, (b) a second fluorescence-labeled antibody (2nd antibody) which bonds to at least one kind of neutrophilic cells, and (c) a third fluorescence-labeled antibody (3rd antibody) which bonds to at least one kind of immature granulocytic cells, in order to stain leukocytic cells in the sample, and removing erythrocytes from the sample; (2) analyzing the resulting sample using a flow cytometer to measure at least one scattered light signal and three separate fluorescence signals; (3) defining a group of granulocytic cells on the basis of intensity of the scattered light and intensity of fluorescence from the 1st antibody; (4) defining neutrophilic cells in the defined group of gra
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: May 31, 2005
    Assignee: Sysmex Corporation
    Inventors: Berend Houwen, Fu-sheng Wang, Hiroyuki Fujimoto, Takashi Sakata, Yukio Hamaguchi
  • Publication number: 20040241770
    Abstract: A method for discriminating and counting erythroblasts comprises the steps of: (i) staining leukocytes in a hematologic sample by adding a fluorescent labeled antibody capable of binding specifically with leukocytes to the hematologic sample; (ii) raising the permeability only of cell membranes of erythroblasts in the hematologic sample to a nucleotide fluorescent dye which does not permeate a cell membrane usually, the nucleotide fluorescent dye having a fluorescent spectrum capable of being distinguished from that of a fluorescent labeling compound of the fluorescent labeled antibody in step (i); (iii) staining nuclei of the erythroblasts in the hematologic sample with the nucleotide fluorescent dye; (iv) subjecting the hematologic sample to flowcytometry to detect at least two fluorescent signals from each cell; and (v) discriminating and counting the erythroblasts from difference in intensity between the at least two fluorescent signals.
    Type: Application
    Filed: June 29, 2004
    Publication date: December 2, 2004
    Inventors: Berend Houwen, Fu-sheng Wang, Tomohiro Tsuji, Takashi Sakata, Yukio Hamaguchi
  • Publication number: 20020006631
    Abstract: A method for discriminating and counting erythroblasts comprises the steps of: (i) staining leukocytes in a hematologic sample by adding a fluorescent labeled antibody capable of binding specifically with leukocytes to the hematologic sample; (ii) raising the permeability only of cell membranes of erythroblasts in the hematologic sample to a nucleotide fluorescent dye which does not permeate a cell membrane usually, the nucleotide fluorescent dye having a fluorescent spectrum capable of being distinguished from that of a fluorescent labeling compound of the fluorescent labeled antibody in step (i); (iii) staining nuclei of the erythroblasts in the hematologic sample with the nucleotide fluorescent dye; (iv) subjecting the hematologic sample to flowcytometry to detect at least two fluorescent signals from each cell; and (v) discriminating and counting the erythroblasts from difference in intensity between the at least two fluorescent signals.
    Type: Application
    Filed: April 9, 1998
    Publication date: January 17, 2002
    Inventors: BEREND HOUWEN, FU-SHENG WANG, TOMOHIRO TSUJI, TAKASHI SAKATA, YUKIO HAMAGUCHI
  • Patent number: 6225124
    Abstract: Aqueous blood-sample diluting reagent and method of its use for compelling a morphological change in a blood sample to yield an MCV value assayed at elapsed time after the sample is drawn to be consistent within a diagnostically acceptable range with the original, immediate post-drawing MCV value. Selection of a small amount of a predetermined surfactant added within a limited range of concentration, and of a salt for adjusting osmotic pressure of the sample is thereby determined. The blood sample is treated with an anti-coagulant agent immediately post-drawing, and for assay in a particle analyzer at post-drawing elapsed time is diluted with the reagent solution. The reagent has an osmotic pressure (&pgr;) of approximately 150-400 mOsm/kg and a pH of 6.0-8.5. The surfactant is present in a 0.0005% to 0.5% concentration and has a hydrophile-lipophile balance (HLB) of 10-20.
    Type: Grant
    Filed: June 2, 1999
    Date of Patent: May 1, 2001
    Assignee: Sysmex Corporation
    Inventors: Berend Houwen, Kinya Uchihashi, Yukio Hamaguchi, Rolf Mast
  • Patent number: 5830701
    Abstract: Improved method for detecting and/or counting the appearance of hematopoietic progenitor cells which comprises the steps of mixing a blood sample with a reagent capable of detecting immature cells without employing any immunological techniques, obtaining cell information about the thus treated sample using a particle analyzer and constructing a cell distribution profile, delineating a portion of the profile as a zone in which at least one subclass of hematopoietic progenitor cells appear, and counting the cells within the zone. The method is capable of detecting the appearance of hematopoietic progenitor cells in a simple and positive manner.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: November 3, 1998
    Assignee: Tao Medical Electronics Co., Ltd.
    Inventors: Berend Houwen, Yukio Tsujino, Takashi Morikawa, Yoshiro Ikeuchi, Yukio Hamaguchi
  • Patent number: 5804448
    Abstract: A method of staining cellular material where a sample containing the cellular material is stained with a stain solution containing a cyanine dye excitable by infrared rays to contrast its nuclear material from its cytoplasmic material.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: September 8, 1998
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Fu-sheng Wang, Berend Houwen
  • Patent number: 5675760
    Abstract: A calculator selects desired data out of a set of data obtained by analyzing a sample, such as blood or urine, and normalizes the selected data with respect to a predetermined level. The normalized values obtained by the calculator may be displayed as values and/or graphs. The graphical display may show a partition line set according to the experiences of the laboratory, so the graph may be quickly understood.
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: October 7, 1997
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Berend Houwen, Shigeo Kanamori, Kaoru Asano
  • Patent number: RE39006
    Abstract: Improved method for detecting and/or counting the appearance of hematopoietic progenitor cells which comprises the steps of mixing a blood sample with a reagent capable of detecting immature cells without employing any immunological techniques, obtaining cell information about the thus treated sample using a particle analyzer and constructing a cell distribution profile, delineating a portion of the profile as a zone in which at least one subclass of hematopoietic progenitor cells appear, and counting the cells within the zone. The method is capable of detecting the appearance of hematopoietic progenitor cells in a simple and positive manner.
    Type: Grant
    Filed: November 7, 2003
    Date of Patent: March 7, 2006
    Assignee: Sysmex Corporation
    Inventors: Berend Houwen, Yukio Tsujino, Takashi Morikawa, Yoshiro Ikeuchi, Yukio Hamaguchi, Fu-sheng Wang, Kojiro Hirai