Patents by Inventor David L. Chastain, Jr.

David L. Chastain, Jr. 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: 4358394
    Abstract: A process for preparing whole blood reference controls having long term stability up to six months for devices using electronic means for whole blood determinations including platelet count and mean cell volume and red blood distribution width. The preconditioning diluent for the red blood cells consists essentially of an aqueous solution of lactose, sodium azide, and a non-ionic surfactant and is pH buffered and osmolality adjusted. The media of the whole blood control includes lactose, fungicides and antibiotics, and supplementary agents including purine nucleosides. It also includes additional components which alter red blood cell membranes including bile salts and cholic acid derivatives, phenothiazine compounds and the salts thereof having antihistamine properties, and 4-aminobenzoic acid ester derivatives and their salts having local anesthetic properties.
    Type: Grant
    Filed: August 12, 1981
    Date of Patent: November 9, 1982
    Assignee: Coulter Electronics, Inc.
    Inventors: Harold R. Crews, David L. Chastain, Jr., Stephen L. Ledis
  • Patent number: 4299726
    Abstract: A process for preparing whole blood reference controls having long term stability up to six months for devices using electronic means for whole blood determinations including platelet count and mean cell volume and red blood distribution width. The preconditioning diluent for the red blood cells consists essentially of an aqueous solution of lactose, sodium azide, and a non-ionic surfactant and is pH buffered and osmolality adjusted. The media of the whole blood control includes lactose, fungicides and antibiotics, and supplementary agents including purine nucleosides. It also includes additional components which alter red blood cell membranes including bile salts and cholic acid derivatives, phenothiazine compounds and the salts thereof having antihistamine properties, and 4-aminobenzoic acid ester derivatives and their salts having local anesthetic properties.
    Type: Grant
    Filed: May 7, 1979
    Date of Patent: November 10, 1981
    Assignee: Coulter Electronics, Inc.
    Inventors: Harold R. Crews, David L. Chastain, Jr., Stephen L. Ledis
  • Patent number: 4286963
    Abstract: This invention relates to a lytic diluent and a method for rapid lysing of red blood cells in whole blood for a differential determination of lymphoid and myeloid populations of leukocytes, and measurement of hemoglobin, particularly for use in automatic particle counting systems.The diluent is a mixture of at least one quaternary ammonium salt having surface active properties, and an additive in suitable proportions, buffered to an acid pH of 3.5 to 5.0. The additive includes 2-phenoxyethanol and other short chain alkanols substituted by one phenyl or phenoxy, as well as certain polyhydroxy compounds.When the reagent is employed in lower concentrations, an alkaline reagent comprising a quaternary ammonium salt and an alkali metal cyanide, buffered to an alkaline pH, may be added to complete the chromagen formation.
    Type: Grant
    Filed: November 23, 1979
    Date of Patent: September 1, 1981
    Assignee: Coulter Electronics, Inc.
    Inventors: Stephen L. Ledis, David L. Chastain, Jr., Harold R. Crews
  • Patent number: 4264470
    Abstract: A method is described for preparing a human platelet analog for use as a reference control in particle analysis instrumentation of the Coulter type. Goat erythrocytes from individual goats which have been selected with respect to age, sex, selective breeding, a controlled environment, prior veterinary treatment, and diet are altered in size and/or combined with samples from several goats, as needed, to obtain a blend for use as a reference control for automated particle counting equipment in which the goat erythrocytes simulate in number, size and distribution the platelets in human whole blood. The controls are useful as a free-standing reference for determination of human platelets only, or can be added to whole blood reference controls for multi-parameter instruments.
    Type: Grant
    Filed: May 7, 1979
    Date of Patent: April 28, 1981
    Assignee: Coulter Electronics, Inc.
    Inventors: David L. Chastain, Jr., Harold R. Crews, Stephen L. Ledis