Patents by Inventor P. Pathak
P. Pathak 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).
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Patent number: 5879688Abstract: A method for alleviating the symptoms of a cosmetic or dermatologic skin condition is described. An effective amount of a poly(hydroxy acid)/polymer conjugate in a pharmaceutically or cosmetically acceptable vehicle is provided. Topical compositions of the conjugates with another cosmetic or dermatological agent, and compounds of the conjugates having attached physiologically active functional groups, are also provided.Type: GrantFiled: October 30, 1996Date of Patent: March 9, 1999Assignee: Focal, Inc.Inventors: Arthur J. Coury, Luis Z. Avila, Chandrashekhar P. Pathak, Shikha P. Barman
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Patent number: 5858746Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules.Type: GrantFiled: January 25, 1995Date of Patent: January 12, 1999Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill, Syed F. A. Hossainy
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Patent number: 5849035Abstract: A method and apparatus for molding polymeric structures in vivo is disclosed. The structures comprise polymers that may be heated to their molding temperature by absorption of visible or near-visible wavelengths of light. By providing a light source that produces radiation of the wavelength absorbed by the polymeric material, the material may be selectively heated and shaped in vivo without a corresponding heating of adjacent tissues or fluids to unacceptable levels. The apparatus comprises a catheter having a shaping element positioned near its distal end. An emitter provided with light from at least one optical fiber is positioned within the shaping element. The emitter serves to provide a moldable polymeric article positioned on the shaping element with a substantially uniform light field, thereby allowing the article to be heated and molded at a desired treatment site in a body lumen.Type: GrantFiled: October 30, 1995Date of Patent: December 15, 1998Assignee: Focal, Inc.Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Jeffrey A. Hubbell, Stephen J. Herman, Laurence A. Roth, Patrick K. Campbell, Kevin M. Berrigan, Peter K. Jarrett, Arthur J. Coury
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Patent number: 5844016Abstract: An improved barrier or drug delivery system which is highly adherent to the surface to which it is applied is disclosed, along with methods for making the barrier. The barrier can be prepared by staining tissue with a photoinitiator, applying a solution containing a polymerizable barrier material solution and a photoinitiator to the tissue, and polymerizing the polymer solution on exposure to light. The resulting polymer adheres strongly to the tissue surface, and also forms a gel in the rest of the applied volume. The polymerizable barrier materials are highly useful for sealing tissue surfaces and junctions against leaks of fluids. The method can be used to adhere preformed barriers to tissue or other surfaces, or to adhere tissue surfaces to each other. Tissue surfaces can be adhered to each other to repair wounds. In addition to photochemical initiators, non-photochemical initiators and combinations of chemical initiators and photochemical initiators can be used.Type: GrantFiled: June 7, 1995Date of Patent: December 1, 1998Assignees: Focal, Inc., The Board of Regents--University of Texas SystemInventors: Amarpreet S. Sawhney, David A. Melanson, Chandrashekar P. Pathak, Jeffrey A. Hubbell, Luis Z. Avila, Mark T. Kieras, Stephen D. Goodrich, Shikha P. Barman, Arthur J. Coury, Ronald S. Rudowsky, Douglas J. K. Weaver
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Patent number: 5843743Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules.Type: GrantFiled: June 6, 1995Date of Patent: December 1, 1998Assignee: Board of Regents, The university of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill, Syed F. A. Hossainy
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Patent number: 5834274Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules.Type: GrantFiled: June 6, 1995Date of Patent: November 10, 1998Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill, Syed F. A. Hossainy
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Patent number: 5801033Abstract: This invention provides novel methods for the formation of biocompatible membranes around biological materials using photopolymerization of water soluble molecules. The membranes can be used as a covering to encapsulate biological materials or biomedical devices, as a "glue" to cause more than one biological substance to adhere together, or as carriers for biologically active species. Several methods for forming these membranes are provided. Each of these methods utilizes a polymerization system containing water-soluble macromers, species which are at once polymers and macromolecules capable of further polymerization. The macromers are polymerized using a photoinitiator (such as a dye), optionally a cocatalyst, optionally an accelerator, and radiation in the form of visible or long wavelength UV light. The reaction occurs either by suspension polymerization or by interfacial polymerization.Type: GrantFiled: June 7, 1995Date of Patent: September 1, 1998Assignee: The Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Syed F. A. Hossainy
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Patent number: 5741323Abstract: A method and apparatus for molding polymeric structures in vivo is disclosed. The structures comprise polymers that may be heated to their molding temperature by absorption of visible or near-visible wavelengths of light. By providing a light source that produces radiation of the wavelength absorbed by the polymeric material, the material may be selectively heated and shaped in vivo without a corresponding heating of adjacent tissues or fluids to unacceptable levels. The apparatus comprises a catheter having a shaping element positioned near its distal end. An emitter provided with light from at least one optical fiber is positioned within the shaping element. The emitter serves to provide a moldable polymeric article positioned on the shaping element with a substantially uniform light field, thereby allowing the article to be heated and molded at a desired treatment site in a body lumen.Type: GrantFiled: June 7, 1995Date of Patent: April 21, 1998Assignee: Focal, Inc.Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Jeffrey A. Hubbell, Stephen J. Herman, Laurence A. Roth, Patrick K. Campbell, Kevin M. Berrigan, Peter K. Jarrett, Arthur J. Coury
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Patent number: 5672358Abstract: A controlled release aqueous emulsion is disclosed, as are its method of manufacture and use as a vehicle for delivering medicaments in liquid form. A contemplated emulsion comprises an oil-in-water emulsion having an average oil particle size of about 100 nm to about 250 nm, a pH value of about 4.5 to about 8.0 and a viscosity at 20.degree.-25.degree. C. of 1 to about 1000 cps. The water phase constitutes at least 25 weight percent of the total composition. The oil phase is a wax matrix that is a wax having a melting point of about 40.degree. to about 80.degree. C. and is present in an amount of about 3 to about 30 percent of the total composition. A pharmaceutically effective amount of a pharmacologically active compound that is free from decomposition at a temperature below about 90.degree. C. is dissolved or dispersed in the wax matrix. The oil and water phases are emulsified by an emulsifying agent that provides freedom from phase separation at a pH value of about 4.Type: GrantFiled: June 19, 1995Date of Patent: September 30, 1997Assignee: Ascent Pharmaceuticals, Inc.Inventors: S. Esmail Tabibi, Robert W. Mendes, Nitin P. Pathak
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Patent number: 5662712Abstract: A method and apparatus for molding polymeric structures in vivo is disclosed. The structures comprise polymers that may be heated to their molding temperature by absorption of visible or near-visible wavelengths of light. By providing a light source that produces radiation of the wavelength absorbed by the polymeric material, the material may be selectively heated and shaped in vivo without a corresponding heating of adjacent tissues or fluids to unacceptable levels. The apparatus comprises a catheter having a shaping element positioned near its distal end. An emitter provided with light from at least one optical fiber is positioned within the shaping element. The emitter serves to provide a moldable polymeric article positioned on the shaping element with a substantially uniform light field, thereby allowing the article to be heated and molded at a desired treatment site in a body lumen.Type: GrantFiled: June 7, 1995Date of Patent: September 2, 1997Assignee: Focal, Inc.Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Jeffrey A. Hubbell, Stephen J. Herman, Laurence A. Roth, Patrick K. Campbell, Kevin M. Berrigan, Peter K. Jarrett, Arthur J. Coury
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Patent number: 5626863Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.Type: GrantFiled: January 27, 1995Date of Patent: May 6, 1997Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill
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Patent number: 5618850Abstract: A method for alleviating the symptoms of a cosmetic or dermatologic skin condition is described. An effective amount of a poly(hydroxy acid)/polymer conjugate in a pharmaceutically or cosmetically acceptable vehicle is provided. Topical compositions of the conjugates with another cosmetic or dermatological agent, and compounds of the conjugates having attached physiologically active functional groups, are also provided.Type: GrantFiled: March 9, 1995Date of Patent: April 8, 1997Assignee: Focal, Inc.Inventors: Arthur J. Coury, Luis Z. Avila, Chandrashekhar P. Pathak, Shikha P. Barman
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Patent number: 5573934Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules.Type: GrantFiled: March 1, 1993Date of Patent: November 12, 1996Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill-West, Syed F. A. Hossainy
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Patent number: 5567435Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.Type: GrantFiled: June 6, 1995Date of Patent: October 22, 1996Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill-West
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Patent number: 5529914Abstract: This invention provides novel methods for the formation of biocompatible membranes around biological materials using photopolymerization of water soluble molecules. The membranes can be used as a covering to encapsulate biological materials or biomedical devices, as a "glue" to cause more than one biological substance to adhere together, or as carriers for biologically active species. Several methods for forming these membranes are provided. Each of these methods utilizes a polymerization system containing water-soluble macromers, species which are at once polymers and macromolecules capable of further polymerization. The macromers are polymerized using a photoinitiator (such as a dye), optionally a cocatalyst, optionally an accelerator, and radiation in the form of visible or long wavelength UV light. The reaction occurs either by suspension polymerization or by interfacial polymerization.Type: GrantFiled: October 7, 1992Date of Patent: June 25, 1996Assignee: The Board of Regents the Univeristy of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Syed F. A. Hossainy
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Patent number: 5410016Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.Type: GrantFiled: March 1, 1993Date of Patent: April 25, 1995Assignee: Board of Regents, The University of Texas SystemInventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill