摘要:
A method is provided for the rapid formation of a biocompatible gel, and may be carried out in situ, i.e., at a selected site within a patient's body. The method involves admixing a biocompatible crosslinking component A having m sulfhydryl groups wherein m≧2 and a biocompatible crosslinking component B having n sulfhydryl-reactive groups wherein n≧2 and m+n>4, wherein the sulfhydryl-reactive groups are capable of covalent reaction with the sulfhydryl groups upon admixture of the components under effective crosslinking conditions to form a gel in less than one minute. Suitable reaction conditions for carrying out the crosslinking reaction will depend on the particular components and the type of reaction involved; that is, the “effective crosslinking conditions” may involve reaction in bulk or in a solvent, addition of a base, and/or irradiation of the admixture in the presence of a free radical initiator. Exemplary uses include tissue augmentation, biologically active agent delivery, bioadhesion, and prevention of adhesions following surgery or injury. Reactive gel-forming compositions and systems are also provided.
摘要:
Pharmaceutically acceptable, non-immunogenic compositions are formed by covalently binding atelopeptide collagen to pharmaceutically pure, synthetic, hydrophilic polymers via specific types of chemical bonds to provide collagen/polymer conjugates. The atelopeptide collagen can be type I, type II or type III and may be fibrillar or non-fibrillar. The synthetic hydrophilic polymer may be polyethylene glycol and derivatives thereof having a weight average molecular weight over a range of from about 100 to about 20,000. The compositions may include other components such as liquid, pharmaceutically acceptable, carriers to form injectable formulations, and/or biologically active proteins such as growth factors. The collagen-polymer conjugates of the invention generally contain large amounts of water when formed. The conjugates can be dehydrated to form a relatively solid object. The dehydrated, solid object can be ground into particles which can be suspended in a non-aqueous fluid such as an oil and injected into a living being for the purpose of providing soft tissue augmentation. Once in place, the particles rehydrate and expand in size five fold or more.
摘要:
Pharmaceutically acceptable, non-immunogenic compositions are formed by covalently binding biologically inactive, natural, biocompatible polymer to pharmaceutically pure, synthetic, hydrophilic polymers via specific types of chemical bonds to provide biocompatible conjugates. The synthetic hydrophilic polymer may be polyethylene glycol and derivatives thereof having a weight average molecular weight over a range of from about 100 to about 20,000. The compositions may include other components such as liquid, pharmaceutically acceptable, carriers to form injectable formulations, and/or biologically active proteins such as growth factors. The conjugates of the invention generally contain large amounts of water when formed. The conjugates can be dehydrated to form a relatively solid object. The dehydrated, solid object can be ground into particles which can be suspended in a non-aqueous fluid such as an oil and injected into a living (preferably human) being for the purpose of providing soft tissue augmentation. Once in place, the particles rehydrate and expand in size five fold or more.
摘要:
Cross-linked hydrogels comprise a variety of biologic and non-biologic polymers, such as proteins, polysaccharides, and synthetic polymers. Such hydrogels preferably have no free aqueous phase and may be applied to target sites in a patient's body by extruding the hydrogel through an orifice at the target site. Alternatively, the hydrogels may be mechanically disrupted and used in implantable articles, such as breast implants. When used in vivo, the compositions are useful for controlled release drug delivery, for inhibiting post-surgical spinal and other tissue adhesions, for filling tissue divots, tissue tracts, body cavities, surgical defects, and the like.
摘要:
The invention provides recombinant procollagen chains having a natural collagen chain separated from one or two propeptides by one or two non-natural site-specific proteolytic agent (e.g., protease) recognition sites. A wide variety of propeptides and site-specific proteolytic agent recognition sites may be used: the selection of particular site-specific proteolytic agent/recognition site pairs is based on the conformation of the resulting procollagen, the availability of the site-specific proteolytic agent, the compatibility of the proteolysis with production of mature collagen, among other factors. Recombinant collagens chains are produced by contacting the subject recombinant procollagen chains with the appropriate site-specific proteolytic agents. Nucleic acids encoding the subject procollagen chains operably linked to transcription regulatory elements are used in vectors and cells for the production of recombinant collagen. Such collagen is used in tissue and cell cultureware and therapeutically, such as in biodegradable surgical materials and for tissue augmentation.
摘要:
The present invention relates to thrombin-containing hemostatic compositions, their preparation and use. In particular, it relates to hemostatic compositions comprising stabilized thrombin and microfibrillar collagen in an aqueous medium. In a preferred embodiment of the present invention, the compositions are used in a kit comprising two different components, one of which is autologous patient's plasma as the source of fibrinogen, and the other of which is the thrombin-containing composition which also contains microfibrillar collagen.
摘要:
Injectable implant compositions comprise a biocompatible ceramic matrix present in a fluid carrier, where the ceramic matrix comprises particles having a size distribution in the range from 50 .mu.m to 250 .mu.m. Optionally, the compositions may further comprise collagen, where the relative amounts of collagen and ceramic matrix at least partly determine the physical properties of implants formed by injecting the compositions. The fluid carrier is an aqueous buffered medium, typically including an organic polymer base material when there is no collagen present in the composition. The compositions are particularly suitable for repair and augmentation of soft and hard tissues by injection.
摘要:
Pharmaceutically acceptable, non-immunogenic compositions are formed by covalently binding atelopeptide collagen to pharmaceutically pure, synthetic, hydrophilic polymers via specific types of chemical bonds to provide collagen/polymer conjugates. The atelopeptide collagen can be type I, type II or type III and may be fibrillar or non-fibrillar. The synthetic hydrophilic polymer may be polyethylene glycol and derivatives thereof having a weight average molecular weight over a range of from about 100 to about 20,000. The compositions may include other components such as liquid, pharmaceutically acceptable, carriers to form injectable formulations, and/or biologically active proteins such as growth factors. The collagen-polymer conjugates of the invention generally contain large amounts of water when formed. The conjugates can be dehydrated to form a relatively solid object. The dehydrated, solid object can be ground into particles which can be suspended in a non-aqueous fluid such as an oil and injected into a living being for the purpose of providing soft tissue augmentation. Once in place, the particles rehydrate and expand in size five fold or more.