Patents by Inventor Takashi Sakata

Takashi Sakata 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: 5618733
    Abstract: A reagent for analyzing leucocytes comprises (a) at least one ionic surfactant, being either a cationic or an amphoteric surfactant, in an amount sufficient for lysing erythrocytes and causing damage to a part of cell membranes of leucocytes; (b) at least one organic compound having a hydrophobic group and an acidic group which has a negative charge in an aqueous solution in an amount sufficient for a preserving leucocyte morphology by combining with a cationic component in leucocytes; (c) a nonionic surfactant; and (d) a buffer for adjusting pH.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: April 8, 1997
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Takashi Sakata, Takashi Morikawa, Kinya Uchihashi, Tomomi Hashimoto
  • Patent number: 5538893
    Abstract: A reagent for analyzing leukocytes having at least one nonionic surfactant having an addition polymerization molar number of polyoxyethylene of 3 to 9, at least one cationic surfactant, and a buffer adjusting a pH value to 2.5 to 4.0, which can determine a cell size of and the morphological features of leukocytes contained in the blood sample.
    Type: Grant
    Filed: April 20, 1995
    Date of Patent: July 23, 1996
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Takashi Sakata, Yasumasa Akai, Kaoru Takarada, Chihiro Kouzuki, Yoshihiro Hyousa
  • Patent number: 5496734
    Abstract: The present invention is a method for blood analysis which provides a rapid treatment of a blood sample so that it can be analysed for counting and classification of leukocytes. Leukocytes are permeablized by treatment with a surfactant solution and labeled, preferably with a fluorescent dye. The method provides labeled leukocytes that can be counted and classified by optical means, including flow cytometry by analysis of a fluorescence signal.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: March 5, 1996
    Assignee: TOA Medical Electronics Co., Ltd.
    Inventor: Takashi Sakata
  • Patent number: 5470751
    Abstract: A reagent for staining malaria infected cells and a method for detecting malaria infected cells using the same, wherein the regent is a staining solution comprising at least one first dye of an Auramine analogue having the formula (I): ##STR1## wherein R.sub.1 to R.sub.6 represents a hydrogen atom, or a methyl or ethyl group, X.sub.1 represents a halogen atom, and at least one second dye of a condensed benzene derivative having the formula (II): ##STR2## wherein A represents ##STR3## R represents a C.sub.1-6 alkyl group, X.sub.2 represents a halogen atom, Y represents --CH.dbd. or --NH--, n represents 0 or 1, and B represents ##STR4## or a phenyl group substituted with 2 lower alkoxy group or with 1 di-lower alkylamino group. A test sample is treated with reagent to stain malaria infected cells. The stained malaria infected cells are then optically detected.
    Type: Grant
    Filed: February 18, 1994
    Date of Patent: November 28, 1995
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Takashi Sakata, Hideaki Matsumoto
  • Patent number: 5308772
    Abstract: A hematological specimen for classifying and counting leukocytes with a flow cytometer is prepared. A sample to be assayed is prepared by eliminating influences of erythrocytes from a hematological sample without changing leukocytes morphologically; adjusting the pH value to a level suitable for staining; and staining the leukocytes with at least two dyes including Astrazon Yellow 3G capable of specifically staining at least basophils and immature granulocytes and Neutral Red capable of specifically staining at least eosinophils. Thus leukocytes contained in the hematological sample can be classified at least three or six groups including immature granulocytes by measuring a single specimen with a flow cytometer.
    Type: Grant
    Filed: June 23, 1992
    Date of Patent: May 3, 1994
    Assignee: TOA Medical Electronics Co. Ltd.
    Inventors: Takashi Sakata, Mitsue Ito
  • Patent number: 5296378
    Abstract: A method for classifying leukocytes with a flow cytometer by use of optical measurements on fluorochrome-stained blood cells. The method comprises the steps of lysing erythrocytes in a blood sample, selectively staining eosinophils and basophils, permitting stained sample to flow through a flow cytometer, and identifying and counting the type of each leukocyte.
    Type: Grant
    Filed: September 18, 1992
    Date of Patent: March 22, 1994
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Takashi Sakata, Tomoyuki Kuroda
  • Patent number: 5264369
    Abstract: A hematological specimen for classifying and counting leukocytes with a flow cytometer is prepared. A sample to be assayed is prepared by eliminating influences of erythrocytes from a hematological sample without changing leukocytes morphologically by adding a first aqueous solution of a low osmotic pressure including a buffer for adjusting the pH value within an acidic region and a second aqueous solution including an osmolarity compensating agent and a buffer for giving pH value suitable for staining, optionally further adding a salt, which dissociates into ions in aqueous solutions so as to control the electrical conductivity of the aqueous solution at a preferable level, while damaging the cell membranes of erythroblasts contained in said sample; and staining the leukocytes with at least four dyes including Astrazon Yellow 3G and Neutral Red.
    Type: Grant
    Filed: June 23, 1992
    Date of Patent: November 23, 1993
    Assignee: TOA Medical Electrics Co., Ltd.
    Inventors: Takashi Sakata, Mitsue Ito
  • Patent number: 5253081
    Abstract: Disclosed herein is an image recording device for recording a plurality of images on a single recording medium.
    Type: Grant
    Filed: December 18, 1991
    Date of Patent: October 12, 1993
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Tsuyoshi Shoji, Toshiharu Yumoto, Takashi Sakata
  • Patent number: 5250437
    Abstract: A reagent for measuring the hemoglobin concentration and counting the number of leukocytes in a blood sample, which contains at least one of a quaternary ammonium salt or a pyridinium salt, having a concentration capable of hemolyzing erythrocytes in the blood and denaturing hemoglobin and at least one of cationic, nonionic or amphoteric surfactants or an oxidant capable of oxidizing heme in hemoglobin, the reagent being capable of dividing leukocytes into two or three fractions, for example, a fraction of lymphocytes, a fraction of monocytes, eosinophils and basophils, and a fraction of neutrophils.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: October 5, 1993
    Assignee: TOA Medical Electronics Co., Ltd.
    Inventors: Syouzou Toda, Takashi Sakata, Yukio Hamaguchi
  • Patent number: 5242832
    Abstract: A reagent, satisfying the undermentioned conditions, is useful for counting the number of leukocytes and measuring the hemoglobin concentration in blood samples. The reagent is free of cyanides and it is able to maintain hemoglobin in a stable state for a prolonged time. The reagent contains at least one cationic surfactant selected from the group consisting of a quaternary ammonium salt of a concentration capable of hemolyzing erythrocytes in the blood and oxidizing hemoglobin and a composition of pyridinium salts; at least one cationic, nonionic or amphoteric surfactant; and at least one hemoglobin stabilizer.
    Type: Grant
    Filed: October 10, 1990
    Date of Patent: September 7, 1993
    Assignee: TOA Medical Electronics Co., Ltd.
    Inventor: Takashi Sakata
  • Patent number: 5179026
    Abstract: Three methods for classifying leukocytes with a flow cytometer by optical measurements on fluorochrome-stained blood cells or those which have been so treated as to provide varying intensity in forward scattered light are useful in the practice of clinical testing. Also included are reagents employed in the practice of such methods.
    Type: Grant
    Filed: February 12, 1991
    Date of Patent: January 12, 1993
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Syouhei Matsuda, Takashi Sakata, Tomoyuki Kuroda
  • Patent number: 5175109
    Abstract: A reagent for classifying leukocytes with a flow cytometer by means of optical measurements on fluorochrome-stained blood cells is included. The reagent is useful in the practice of clinical testing and includes a Neutral Red fluorochrome and either an Astrazon Organe G or an Auramine O fluorochrome to enable differentiation of leukocytes.
    Type: Grant
    Filed: February 28, 1991
    Date of Patent: December 29, 1992
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Takashi Sakata, Tomoyuki Kuroda
  • Patent number: 5087971
    Abstract: A video signal processing device is incorporated in an image output device such as a thermal printer which is connected to an analog video signal source such as a computerized medical diagnostic imaging system, e.g., a CT scanner. The video signal processing device has a memory which stores data for determining the total number of horizontal pixels along a single horizontal line in a frame based on the number of frames to be displayed on a display unit or recorded on a recording medium, and the aspect ratio of the frames, and data for determining the frequency of the sampling pulses supplied to an A/D converter based on the total number of horizontal pixels and the number of scanning lines of the analog video signal. Based on the data stored in the memory, a processor supplies sampling pulses to the A/D converter depending on input and output conditions which are entered through a control panel by the operator.
    Type: Grant
    Filed: October 25, 1990
    Date of Patent: February 11, 1992
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takashi Sakata, Toshiharu Yumoto
  • Patent number: 5039613
    Abstract: Three methods for classifying leukocytes with a flow cytometer by optical measurements on fluorochrome-stained blood cells or those which have been so treated as to provide varying intensity in forward scattered light are useful in the practice of clinical testing. Also included are reagents employed in the practice of such methods.
    Type: Grant
    Filed: September 1, 1987
    Date of Patent: August 13, 1991
    Assignee: Toa Medical Electronics Co., Ltd.
    Inventors: Syouhei Matsuda, Takashi Sakata, Tomoyuki Kuroda
  • Patent number: 4933293
    Abstract: A method for classifying leukocytes with a flow cytometer by means of optical measurements on fluorochrome-stained blood cells is useful in the practice of clinical testing.
    Type: Grant
    Filed: October 12, 1989
    Date of Patent: June 12, 1990
    Assignee: TOA Medical Electronics Co., Ltd.
    Inventors: Tomoyuki Kuroda, Takashi Sakata