Patents by Inventor David J. Buttle

David J. Buttle 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: 5468480
    Abstract: A pharmaceutical composition comprising purified chymopapain and a reducing agent is presented. The purified chymopapain in this composition has a specific activity against 1 mM of N-.alpha.-benzoyl-DL-arginine p-nitroanilide at 40.degree. C. and pH 6.8 of between 3,000 and 4,500 units per mg, and contains less than 0.2% each of papaya proteinase III (PPIII), papain, and papaya proteinase IV (PPIV).
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: November 21, 1995
    Assignee: The Boots Company PLC
    Inventors: Alan J. Barrett, David J. Buttle, Daniel H. Rich
  • Patent number: 5380656
    Abstract: A method of purifying chymopapain by active site directed affinity chromatography using inhibitory dipeptides as affinity ligands is presented. The inhibitory dipeptides have C-terminal aldehyde derivatives of phenylalanine selected from the group consisting of the semicarbazone, the methoxyimine and the oxime. The purified chymopapain has a specific activity against BAPNA (1 mM) at 40.degree. C. and pH 6.8 of between 3000 and 4500 units per mg and contains less than 0.2% each of papaya proteinase III (PPIII), papain and papaya proteinase IV (PPIV). The use of purified chymopapain in pharmaceutical compositions for the treatment of damaged mammalian spinal discs is also disclosed.
    Type: Grant
    Filed: December 13, 1991
    Date of Patent: January 10, 1995
    Assignee: The Boots Company PLC
    Inventors: Alan J. Barrett, David J. Buttle, Daniel H. Rich
  • Patent number: 5106621
    Abstract: A cysteine proteinase characterized in that it is immunologically distinct, has a molecular mass of about 25,000 and has a distinct net charge is disclosed. "Ananain" and "comosain" are such enzymes, which may be distinguished by their specificities for certain synthetic substrates.A process for the production thereof is also disclosed which comprises separation from pineapple plant material and purification. Such enzymes may be used in the debridement of eschar tissues.
    Type: Grant
    Filed: November 30, 1990
    Date of Patent: April 21, 1992
    Inventors: Andrew D. Rowan, David J. Buttle