摘要:
A method of preventing adhesions by topical administration of fibrinolysis enhancing agents is described. The method uses a topically applied polymeric matrix for delivery of a fibrinolytic agent, preferably urokinase, tPA, hirudin, or most preferably, ancrod. In the most preferred embodiment, the matrix is extremely thin and is polymerized in situ to form a biodegradable polymeric matrix. The matrix provides controlled release of the agent over a period of time effective to prevent surgical adhesions and is biodegradable, usually within the same time frame. Examples demonstrate that the combination of the matrix and the urokinase, tPA, hirudin, or ancrod is effective in preventing surgical adhesions.
摘要:
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.
摘要:
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.
摘要:
Described herein is a multi-functional polymeric material for use in inhibiting adhesion and immune recognition between cells and cells, cells and tissues, and tissues and tissues. One component of the polymeric material adsorbs well to cells or tissue, and the other component of the polymeric material does not adsorb well to tissues. A water-soluble polymer that does not bear charge (polynonion) is used as the non-binding component, and a water soluble polymer that is positively charged at physiological pH (polycation) is used as the tissue binding component. When the bi-functional polymeric material contacts a tissue, the tissue-binding component binds and thus immobilizes the attached non-binding component, which will then extend generally away from the tissue surface and sterically block the attachment of other tissues. The method and compositions are useful in inhibiting formation of post-surgical adhesions, protecting damaged blood vessels from thrombosis and restenosis, and decreasing the extent of metastasis of attachment-dependent tumor cells.
摘要:
Described herein is a multi-functional polymeric material for use in inhibiting adhesion and immune recognition between cells and cells, cells and tissues, and tissues and tissues. One component of the polymeric material adsorbs well to cells or tissue, and the other component of the polymeric material does not adsorb well to tissues. A water-soluble polymer that does not bear charge (polynonion) is used as the non-binding component, and a water soluble polymer that is positively charged at physiological pH (polycation) is used as the tissue binding component. When the bi-functional polymeric material contacts a tissue, the tissue-binding component binds and thus immobilizes the attached non-binding component, which will then extend generally away from the tissue surface and sterically block the attachment of other tissues. The method and compositions are useful in inhibiting formation of post-surgical adhesions, protecting damaged blood vessels from thrombosis and restenosis, and decreasing the extent of metastasis of attachment-dependent tumor cells.
摘要:
Described herein is a multi-functional polymeric material for use in inhibiting adhesion and immune recognition between cells and cells, cells and tissues, and tissues and tissues. One component of the polymeric material adsorbs well to cells or tissue, and the other component of the polymeric material does not adsorb well to tissues. A water-soluble polymer that does not bear charge (polynonion) is used as the non-binding component, and a water soluble polymer that is positively charged at physiological pH (polycation) is used as the tissue binding component. When the bi-functional polymeric material contacts a tissue, the tissue-binding component binds and thus immobilizes the attached non-binding component, which will then extend generally away from the tissue surface and sterically block the attachment of other tissues. The method and compositions are useful in inhibiting formation of post-surgical adhesions, protecting damaged blood vessels from thrombosis and restenosis, and decreasing the extent of metastasis of attachment-dependent tumor cells.
摘要:
A method of preventing adhesions by topical administration of fibrinolysis enhancing agents is described. The method uses a topically applied polymeric matrix for delivery of a fibrinolyic agent, preferably urokinase, or tPA. In the most preferred embodiment, the matrix is extremely thin and is polymerized in situ to form a biodegradable polymeric matrix. The matrix provides controlled release of the agent over a period of time effective to prevent surgical adhesions and is biodegradable, usually within the same time frame. Examples demonstrate that the combination of the matrix and the urokinase or tPA is effective in preventing surgical adhesions.
摘要:
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.
摘要:
Described herein is a multi-functional polymeric material for use in inhibiting adhesion and immune recognition between cells and cells, cells and tissues, and tissues and tissues. One component of the polymeric material adsorbs well to cells or tissue, and the other component of the polymeric material does not adsorb well to tissues. A water-soluble polymer that does not bear charge (polynonion) is used as the non-binding component, and a water soluble polymer that is positively charged at physiological pH (polycation) is used as the tissue binding component. When the bi-functional polymeric material contacts a tissue, the tissue-binding component binds and thus immobilizes the attached non-binding component, which will then extend generally away from the tissue surface and sterically block the attachment of other tissues. The method and compositions are useful in inhibiting formation of post-surgical adhesions, protecting damaged blood vessels from thrombosis and restenosis, and decreasing the extent of metastasis of attachment-dependent tumor cells.
摘要:
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, and coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules. A medical condition at a localized site is treated by applying a polymerization initiator and then applying a substantially water-soluble, degradable macromer of at least 200 mw and having at least two crosslinkable substituents, and polymerizing the macromer to form a crosslinked polymeric material at the site. The crosslinked polymeric material may adhere two surfaces together, or be a barrier that provides immunoisolation or prevents adhesion of the site to another surface such as post-surgical adhesion. A biologically active material may be present when the macromer is polymerized to provide for delivery of the biologically active material, or to provide the polymeric material with a desired property such as resistance to bacterial growth or a decrease in inflammatory response.