710 results about "Fibrinogen" patented technology

A device and method for applying a fibrinogen-based tissue sealant to seamlessly connect human or animal tissues or organ parts, to seal wounds, stop bleeding and the like by mixing fibrin or fibrinogen with blood clot-promoting coagulation factors are disclosed. The device includes two cylindrical compartments for separately containing the separate fluid components of the sealant preparation, which are simultaneously displaced from the respective compartments by plungers commonly depressable with the same effective strokes. The plungers may be depressed directly or by a common mechanism (e.g., rack and pinion) for accurately controlling the rate of dispensing fluid. The cylindrical compartments are of the same or different cross-sectional area and are arranged either concentrically or side-by-side. The device further includes structure for merging the two fluid components within an outer sleeve housing an inner needle. The sleeve and needle contain conduits for the flow of the two fluid sealant components as they are expressed from the respective compartments. Also disclosed are a convenient device for filling the two compartments, structure for mixing the fluid components, and for atomizing the effluent sealant fluid stream (i.e., spraying).

The present invention relates to a haemostatic multilayer bandage that comprises preferably a thrombin layer between two fibrinogen layers. The dressing may contain other resorbable materials such as glycolic acid or lactic acid based polymers or copolymers. The inventive haemostatic bandage is useful for the treatment of wounded tissue.

A method for specifically removing or isolating plasmin(ogen) or plasmin in presence of fibrinogen from a mixture containing plasmin(ogen) or plasmin by contacting the mixture with a rigid amino acid wherein the amino group of the amino acid and the carboxylic group of the amino acid are about 6–8 Angstroms, preferably about 7 Angstroms apart and the rigid amino acid is covalently bound to the support via the amino group of the amino acid.

Methods and compositions are provided for preparing protein concentrates from protein comprising aqueous compositions. In the subject methods, an initial protein comprising aqueous compositions, such as whole blood or a derivative thereof, is contacted with a non-protein denaturant hydrogel under conditions sufficient for a substantial amount of water present in the composition to be absorbed by the hydrogel, resulting in the production of a protein concentrate, such as a fibrinogen rich composition. Of particularl interest is the use of the subject methods to prepare fibrinogen rich compositions, where such compositions produced according to the subject invention are useful in fibrin sealants, drug delivery vehicles and in a number of other diverse applications.

Disclosed are processes for preparing solid dressings for treated wounded tissue in mammalian patients, such as a human, comprising a haemostatic layer consisting essentially of a fibrinogen component and a fibrinogen activator. Also disclosed are methods for treating wounded tissue using these dressings and frozen and liquid compositions useful for preparing the haemostatic layer(s) of these dressings or for treating wounded tissue in a mammal.

The present invention is directed to a hemostatic textile, comprising: a material comprising a combination of glass fibers and one or more secondary fibers selected from the group consisting of silk fibers; ceramic fibers; raw or regenerated bamboo fibers; cotton fibers; rayon fibers; linen fibers; ramie fibers; jute fibers; sisal fibers; flax fibers; soybean fibers; corn fibers; hemp fibers; lyocel fibers; wool; lactide and/or glycolide polymers; lactide/glycolide copolymers; silicate fibers; polyamide fibers; feldspar fibers; zeolite fibers, zeolite-containing fibers, acetate fibers; and combinations thereof; the hemostatic textile capable of activating hemostatic systems in the body when applied to a wound. Additional cofactors such as thrombin and hemostatic agents such as RL platelets, RL blood cells; fibrin, fibrinogen, and combinations thereof may also be incorporated into the textile. The invention is also directed to methods of producing the textile, and methods of using the textile to stop bleeding.

A method for preparing and resulting articles of manufacture comprising a substrate having a surface, a bulk beneath the surface, and a grafted polymer layer on the substrate surface, the substrate surface and the grafted polymer layer, in combination, constituting a modified surface having a fibrinogen adsorption of less than about 125 ng/cm² in a fibrinogen binding assay in which the modified surface is incubated for 60 minutes at 37° C. in 70 μg/mL fibrinogen derived from human plasma containing 1.4 μg/mL I-125 radiolabeled fibrinogen.

Bioscaffoldings formed of hydrogels that are crosslinked in situ in an infarcted region of the heart (myocardium) by a Michael's addition reaction or by a disulfide bond formed by an oxidative process are described. Each of the bioscaffoldings described includes hyaluronan as one of the hydrogel components and the other component is selected from collagen, collagen-laminin, poly-l-lysine, and fibrin. The bioscaffolding may further include an alginate component. The bioscaffoldings may have biofunctional groups such as angiogenic factors and stem cell homing factors bound to the collagen, collagen-laminin, poly-l-lysine, or fibrinogen hydrogel component. In particular, the biofunctional groups may be PR11, PR39, VEGF, bFGF, a polyarginine/DNA plasmid complex, or a DNA/polyethyleneimine (PEI) complex. Additionally, the hydrogel components may be injected into the infarct region along with stem cells and microspheres containing stem cell homing factors. The bioscaffolding may be formed on a stent or a cardiac medical device.

The invention is a fibrin glue that avoids the use of fibrinogen and thus eliminates the need for premixing and premature clot formation. The fibrin glue of the invention comprises thrombin, thromboplastin and calcium and may have clotting Factors, VII, IX and X, and the like. The invention also comprises a biosealant for use with the fibrin glue without fibrinogen or for use alone. The biosealant is a two component mixture of gelatin/resorcinol and glyoxal/glutaraldehyde/4-(p-maleimidophenyl) butyric acid. The two components are mixed on use.

The invention generally relates to dextran fibers which are preferably electrospun and devices formed from such fibers. In particular, such devices may include substances of interest (such as therapeutic substances) associated with the electrospun fibers. Upon exposure to a liquid the electrospun fibers dissolve immediately and the substances of interest are released into the liquid. Exemplary devices include bandages formed from electrospun dextran fibers and associated agents that promote hemostasis, such as thrombin and fibrinogen.

The present invention relates to biodegradable scaffolds composed of a naturally-occurring protein backbone cross-linked by a synthetic polymer. Specifically, the present invention provides PEGylated-fibrinogen scaffold and methods of generating and using same for treating disorders requiring tissue regeneration.

Selective occlusion of a blood vessel is achieved by selectively damaging endothelial cells at a target location in the blood vessel, resulting in the formation of a fibrin clot proximate to the damaged endothelial cells. Additional fibrinogen can then be introduced into the blood vessel if occlusion is not achieved, as the fibrinogen is converted to fibrin by enzymes released by the exposed thrombogenic tissue and activated platelets. Endothelial cells are selectively damaged using thermal effects induced by ultrasound, by mechanical effects induced by ultrasound, or by mechanical effects produced by a tool introduced into the blood vessel (such as a catheter-based tool). A particularly preferred technique for selectively damaging endothelial cells involves introducing an ultrasound activatable agent into the blood vessel, and causing cavitation in that agent using pulses of high-intensity focused ultrasound having a duration insufficient to induce thermal damage in adjacent perivascular tissue.

This invention describes a bioerodible fibrin material which is obtained by mixing fibrinogen and thrombin reconstituted or diluted with a particular high tonic strength medium, free of calcium. Such a fibrin-based biomaterial develops a tight structure with thin fibers and small pore size suitable for use as an anti-adhesion barrier. In this invention, thrombin is no longer the variable which governs the tightness and the porosity of the fibrin material obtained, but still controls the clotting time. The mechanical behavior, high-water capacity, and releasable retention properties for therapeutic agents of this fibrin structure causes the fibrin material to be ideally suited for use as a drug delivery device, capable of delivering proteins, hormones, enzymes, antibiotics, antineoplastic agents and even cells for local and systemic treatment of human and non-human patients.

A method of preparing a collagen sponge comprises mixing air into a collagen gel, so as to obtain a collagen foam which is dried. From the dried product thereby obtained, collagen sponge is obtained by isolating parts of sponge with a chamber diameter of more than 0.75 mm and less than 4 mm, or parts with an average chamber diagonal dimension of 3 mm. The collagen sponge may be used as a material for sealing wounds, possibly with a coating comprising a fibrin glue, such as a combination of fibrinogen, thrombin and aprotinin. A device for extracting a part of a collagen foam and for degenerating another part of the collagen foam to a collagen gel is disclosed. An elongated collagen sponge having a through-going hole or bore and a flexible wall may be used for re-establishing walls in a mammalian gastrointestinal funnel or trachea system.

The present invention provides binding moieties for fibrin which have a variety of uses wherever detecting, isolating or localizing fibrin, and particularly fibrin as opposed to fibrinogen, is advantageous. Particularly disclosed are synthetic, isolated polypeptides capable of binding fibrin and recognizing the form of polymerized fibrin found in thrombi. In addition, the polypeptides have a slow dissociation rate from fibrin, which improves their ability to form a contrast image at the site of a fibrin clot, making the disclosed binding moieties particularly useful as imaging agents for thrombi.

A plasma concentrator of this invention having a concentrator chamber, concentrator gel beads, a filter, and an agitator. The agitator has agitator blades extending outwardly from the lower end. The agitator end is positioned in the concentrator chamber and supported for rotation about its central axis and for reciprocal movement along its central axis. The concentrator has a top with an upper opening through which the upper end of the actuator stem extends, and a lower opening in which the filter is positioned. The concentrator chamber can have a cylindrical inner wall, and the agitator blades can have an outer edge in close proximity to the inner wall with the space between the outer edge and the inner wall being less than the diameter of the gel beads. The filter is selected to block effective flow of plasma therethrough under ambient gravity conditions and permit plasma and plasma concentrate flow therethrough under centrifugal forces of the separation gravity. The method concentrates plasma by removing water without significantly denaturing the fibrinogen in the plasma. The plasma is introduced into a concentration chamber containing a plurality of dehydrated concentrator gel beads and an agitator. Then water is removed from the plasma while stirring the beads to reduce plasma polarization and breaking up clumps of beads that form during the agitation. Then centrifugal force can be applied to the concentrated plasma in an amount sufficient to separate a substantial portion of the plasma concentrate from the beads.

Methods and apparatus for a free-standing biodegradable patch suitable for medical applications, especially intravascular, minimally-invasive and intraoperative surgical applications are provided, wherein the patch comprises a free-standing film or device having a mixture of a solid fibrinogen component and a solid thrombin component that, when exposed to an aqueous environment, undergoes polymerization to form fibrin. In alternative embodiments the patch may comprise a solid fibrinogen component, with or without an inorganic calcium salt component. The patch may take a non-adherent form during delivery to a target location within a vessel or tissue, and thereafter may be activated to adhere to vessel wall or tissue, and may include a number of additives, including materials to improve the mechanical properties of the patch, or one or more therapeutic or contrast agents.

The disclosed methods and compositions for reducing cardiovascular risk factors in mammals generally includes using genistein to modulate various inflammatory and cardiovascular risk markers including: homocysteine, C-reactive protein, fibrinogen, sex hormone-binding globulin, fasting glucose, insulin, insulin resistance, and osteoprotegerin.

Size-selective hemocompatible porous polymeric adsorbents are provided with a pore structure capable of excluding molecules larger than 50,000 Daltons, but with a pore system that allows good ingress and egress of molecules smaller than 35,000 Daltons. The pore system in these porous polymeric adsorbents is controlled by the method of synthesis so that 98% of the total pore volume is located in pores smaller than 300 Angstroms (Å) in diameter with a working pore size range within 100 to 300 Å in diameter. The porous polymeric adsorbents of this invention are very selective for extracting midsize proteins, such as cytokines and β₂-microglobulin, from blood and other physiologic fluids while keeping the components required for good health such as cells, platelets, albumin, hemoglobin, fibrinogen, and other serum proteins intact.

A therapeutic medical article is provided which comprises a medical article, a precursor compound and an activator compound. The medical article is adapted, upon administration to a patient, to release the precursor compound and the activator compound such that the activator compound interacts with the precursor compound and converts the precursor compound into activated form for local delivery. Specific examples of precursor and activator compound pairs include: (a) a nitrosothiol precursor and a nitric oxide donor, (b) plasminogen and plasminogen activator, and (c) fibrinogen and thrombin.

Disclosed are solid dressings for treated wounded tissue in mammalian patients, such as a human, comprising a haemostatic layer consisting essentially of a fibrinogen component and thrombin, wherein the thrombin is present in an amount between 0.250 Units/mg of fibrinogen component and 0.062 Units/mg of fibrinogen component. Also disclosed are methods for treating wounded tissue.