Patents by Inventor Naoki Asakawa

Naoki Asakawa 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: 6951885
    Abstract: The present invention relates to a pharmaceutical composition containing a cycloalkene compound, a salt thereof or a prodrug thereof, and a nonionic surfactant and/or a cyclodextrin derivative readily soluble in water, and a method for improving solubility, stability or coloring property of the compound, a salt thereof or a prodrug thereof.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: October 4, 2005
    Assignee: Takeda Pharmaceutical Company Limited
    Inventors: Naoki Asakawa, Masao Nagao
  • Patent number: 6929741
    Abstract: The present invention provides a packing for chromatography. Specifically, it provides a packing for chromatography in which a hydrophilic polymeric material is bound to the surface of a porous carrier, and a carbon chain is chemically bound inside the pore. By the use of the packing according to the present invention for analysis of low molecular weight compounds in a biological sample, a pretreatment such as removal of proteins etc. becomes unnecessary, and the biological sample can be directly analyzed.
    Type: Grant
    Filed: February 9, 2001
    Date of Patent: August 16, 2005
    Assignee: Eisai Co., Ltd.
    Inventors: Eiichi Yamamoto, Kaoru Murata, Yasushi Ishihama, Naoki Asakawa
  • Publication number: 20050000875
    Abstract: Device for improving detection sensitivity in low flow velocity high performance liquid chromatographic apparatus. Preferredly, diffusion promoting device connected at just before separation column and having function of improving detection sensitivity for use in low flow velocity high performance liquid chromatographic apparatus. Also, method for improving detection sensitivity in low flow velocity high performance liquid chromatographic apparatus.
    Type: Application
    Filed: June 28, 2004
    Publication date: January 6, 2005
    Inventors: Kaoru Murata, Nariyasu Mano, Naoki Asakawa
  • Publication number: 20040180930
    Abstract: The present invention provides a novel compound exhibiting an excellent suppressing effect to cell injury caused by radicals and neurotoxicity induced by excitatory nuerotransmitters such as glutamate. Specifically, it provides a compound represented by the following formula, a salt thereof or a hydrate of them.
    Type: Application
    Filed: October 9, 2003
    Publication date: September 16, 2004
    Inventors: Akinori Akaike, Hachiro Sugimoto, Yukio Nishizawa, Masahiro Yonaga, Naoki Asakawa, Naoki Asai, Nariyasu Mano, Taro Terauchi, Takashi Doko
  • Patent number: 6780325
    Abstract: The present invention provides a device for improving detection sensitivity and a method for improving the detection sensitivity for use in a low flow velocity high performance liquid chromatographic apparatus. That is, the present invention is a diffusion promoting device connected at just before a separation column and having a function for improving detection sensitivity for use in a low flow velocity high performance liquid chromatographic apparatus.
    Type: Grant
    Filed: May 10, 2001
    Date of Patent: August 24, 2004
    Assignee: Eisai Co., Ltd.
    Inventors: Kaoru Murata, Nariyasu Mano, Naoki Asakawa
  • Patent number: 6723347
    Abstract: A process for conveniently producing a stable protein powder retaining the higher-order structure at a high level which comprises freezing a protein-containing solution at a cooling rate of about −300 to −10° C./min. and then drying.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: April 20, 2004
    Assignee: Takeda Chemical Industries, Ltd.
    Inventors: Yutaka Yamagata, Takayuki Doen, Naoki Asakawa, Shigeyuki Takada
  • Publication number: 20030216475
    Abstract: The present invention relates to a pharmaceutical composition containing a compound represented by the formula: 1
    Type: Application
    Filed: January 29, 2003
    Publication date: November 20, 2003
    Inventors: Naoki Asakawa, Masao Nagao, Jun Sato
  • Publication number: 20030191157
    Abstract: An injectable composition comprises a benzimidazole compound having an antiulcer action and a strong alkali (e.g., an alkali metal hydroxide such as sodium hydroxide) in a proportion of about 1 equivalent of the latter relative to 1 mol of the former, and is substantially free from a nonaqueous solvent. The injectable composition may comprise N-methylglucamine, and a saccharide (such as mannitol). The injectable composition may be a freeze-dried preparation. The freeze-dried preparation is dissolvable in or dilutive with a distilled water for injection or an infusion solution without a nonaqueous solvent. The injectable composition is useful as an antiulcer agent.
    Type: Application
    Filed: February 14, 2003
    Publication date: October 9, 2003
    Inventors: Takayuki Doen, Masao Nagao, Naoki Asakawa, Nobuyuki Takechi
  • Patent number: 6581442
    Abstract: The present invention provides a device capable of simply formulating an arbitrary gradient pattern in a low flow gradient high performance liquid chromatography. That is, the present invention provides a split tubing apparatus for a gradient high performance liquid chromatography, which comprises a solvent inlet part, a split tubing part split into two or more plural tubes, and a solvent outlet part.
    Type: Grant
    Filed: November 19, 2001
    Date of Patent: June 24, 2003
    Assignee: Eisai Co., Ltd.
    Inventors: Kaoru Murata, Yasushi Ishihama, Nariyasu Mano, Naoki Asakawa
  • Publication number: 20030003311
    Abstract: The present invention provides a packing for chromatography. Specifically, it provides a packing for chromatography in which a hydrophilic polymeric material is bound to the surface of a porous carrier, and a carbon chain is chemically bound inside the pore. By the use of the packing according to the present invention for analysis of low molecular weight compounds in a biological sample, a pretreatment such as removal of proteins etc. becomes unnecessary, and the biological sample can be directly analyzed.
    Type: Application
    Filed: July 22, 2002
    Publication date: January 2, 2003
    Inventors: Eiichi Yamamoto, Kaoru Murata, Yasushi Ishihama, Naoki Asakawa
  • Patent number: 6498040
    Abstract: A high-performance liquid chromatography apparatus and a process for conversion of mobile phase, enabling a trace amount of sample for NMR analysis to be efficiently separated and prepared, includes steps of separating a target ingredient from the sample by the high-performance liquid chromatography, trapping the target ingredient in a trapping column using a different mobile phase, replacing water by deuterium oxide and eluting this target ingredient from the trapping column using deuterated solvent other than deuterium oxide.
    Type: Grant
    Filed: February 10, 2000
    Date of Patent: December 24, 2002
    Assignee: Eisai Co., Ltd.
    Inventors: Yumi Yokoyama, Naoya Kishi, Masayuki Tanaka, Naoki Asakawa
  • Patent number: 6485642
    Abstract: A sample solution is sent into a concentration column through a three-way joint and a three-way switching valve to trap and concentrate the sample components on the concentration column, followed by injecting the sample solution into an injector by operating a first dilution solvent pump. When a large volume of the sample solution is to be sent or when the sample solution has a high solvent strength, trapping and concentration on the concentration column may be facilitated by replacing the sample solvent with a second dilution solvent by allowing the second dilution solvent to flow into the three-way joint after setting the flow rate of the second dilution solvent from a second dilution solvent vessel to a prescribed flow rate using a second dilution solvent pump.
    Type: Grant
    Filed: June 5, 2001
    Date of Patent: November 26, 2002
    Assignees: Shimadzu Corporation, Eisai Co., Ltd.
    Inventors: Katsuaki Kaito, Yosuke Iwata, Kaoru Murata, Naoki Asakawa
  • Publication number: 20020011437
    Abstract: A sample solution is sent into a concentration column through a three-way joint and a three-way switching valve to trap and concentrate the sample components on the concentration column, followed by injecting the sample solution into an injector by operating a first dilution solvent pump. When a large volume of the sample solution is to be sent or when the sample solution has a high solvent strength, trapping and concentration on the concentration column may be facilitated by replacing the sample solvent with a second dilution solvent by allowing the second dilution solvent to flow into the three-way joint after setting the flow rate of the second dilution solvent from a second dilution solvent vessel to a prescribed flow rate using a second dilution solvent pump.
    Type: Application
    Filed: June 5, 2001
    Publication date: January 31, 2002
    Inventors: Katsuaki Kaito, Yosuke Iwata, Kaoru Murata, Naoki Asakawa
  • Patent number: 5900144
    Abstract: Disclosed is an optical isomer separating agent composed of a stationary phase having a support and a chemically modified conalbumin. The separating agent may be used in a high-performance liquid chromatography column.
    Type: Grant
    Filed: June 2, 1993
    Date of Patent: May 4, 1999
    Assignee: Eisai Co., Ltd.
    Inventors: Nariyasu Mano, Yoshiya Oda, Toshinobu Miwa, Naoki Asakawa, Yutaka Yoshida, Tadashi Sato
  • Patent number: 5480542
    Abstract: A packing for chromatography whereby a low molecular weight substance contained in biological samples can be analyzed directly at a high accuracy without any pretreatments. This packing is combining a protein such as avidin and ovomucoid to the support via a straight or branched spacer optionally having a functional group such as a cyano group. Enantiomers interact differentially with proteins, and thereby optically separated. Further, a purification column packed with said packing is disclosed. According to the present invention, a low molecular weight substance can be directly and accurately analyzed without requiring any pretreatment for removing biological macromolecules. When it is employed in the purification column, the time required for the pretreatment can be shortened.
    Type: Grant
    Filed: August 22, 1994
    Date of Patent: January 2, 1996
    Assignee: Eisai Co., Ltd.
    Inventors: Naoki Asakawa, Yoshiya Oda, Yutaka Yoshida, Tadashi Sato
  • Patent number: 5425943
    Abstract: An injection composition comprises a pharmacologically effective amount of a modified tPA, 47.5 mM or more of an amino acid or a salt thereof and is improved in view of stability and solubility.
    Type: Grant
    Filed: June 22, 1992
    Date of Patent: June 20, 1995
    Assignee: Eisai Co., Ltd.
    Inventors: Masahiro Kawahara, Yuichiro Hayashi, Naoki Asakawa, Sumio Watanabe, Yasuo Miyake
  • Patent number: 5354461
    Abstract: A packing for chromatography whereby a low molecular weight substance contained in biological samples can be analyzed directly at a high accuracy without any pretreatments. This packing is combining a protein such as avidin and ovomucoid to the support via a straight or branched spacer optionally having a functional group such as a cyano group. Enantiomers interact differentially with proteins, and thereby optically separated. Further, a purification column packed with said packing is disclosed.According to the present invention, a low molecular weight substance can be directly and accurately analyzed without requiring any pretreatment for removing biological macromolecules. When it is employed in the purification column, the time required for the pretreatment can be shortened.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: October 11, 1994
    Assignee: Eisai Co., Ltd.
    Inventors: Naoki Asakawa, Yoshiya Oda, Yutaka Yoshida, Tadashi Sato
  • Patent number: 5201969
    Abstract: A radial tire for heavy duty vehicles having a steel belt layer with triangular structure which is composed of at least three belt plies of steel belt disposed on a carcass, and a middle layer which contains cords of aromatic polyamide fibers which is laid between first belt ply and second belt ply viewed from tread surface side among the belt plies.The middle layer has skirts which are folded over from a main portion of the middle layer and laid between the first and second belt plies so as to wrap around each axial outer end of the first belt ply.The cords of the first belt play and the cords of the second belt ply cross each other at an angle of from 10 to 30 deg. against the tire equator, and the cords of the middle layer slant in the same direction as that of first belt ply at an angle of 3 deg. or less against that of first belt ply.
    Type: Grant
    Filed: July 23, 1990
    Date of Patent: April 13, 1993
    Assignee: Sumitomo Rubber Industries, Ltd.
    Inventors: Minoru Nishi, Yoshiyuki Takada, Naoki Asakawa
  • Patent number: 5117109
    Abstract: The components present in the sample with a mobile phase A in 1st section is separated. In 2nd section there is provided with an inserting line of a dilute solution for diluting the mobile phase A and a trapping column which forces the dilute solution to pass but catches the components by connecting said line to said column. In 3rd section, the components caught by the trapping column are introduced into mass spectrometer by using a mobile phase B. It is preferable to use respectively different mobile phases for the mobile phase A and the mobile phase B. It is good to install separating columns in 1st and 3rd sections. It is also desired to add the retaining apparatus of the components separated in 1st section.
    Type: Grant
    Filed: September 6, 1990
    Date of Patent: May 26, 1992
    Assignee: Eisai Co. Ltd.
    Inventors: Naoki Asakawa, Hiroshi Ohe, Yutaka Yoshida, Tadashi Sato, Yukuo Nezu, Yoshiya Oda
  • Patent number: 4985245
    Abstract: A medical composition which contains a tissue Plasminogen Activator (tPA) in combination with meglumine or a salt thereof.
    Type: Grant
    Filed: November 3, 1989
    Date of Patent: January 15, 1991
    Assignee: Eisai Co., Ltd.
    Inventors: Fumio Kakimoto, Naoki Asakawa, Yasuo Ishibashi, Yasuo Miyake