摘要:
A bioerodible polymeric semi-IPN alloy which comprises a first bioerodible polymer capable of producing acidic products upon hydrolytic degradation; a second bioerodible polymer, which provides a biopolymeric scaffolding or internal reinforcement; and optionally a buffering compound that buffers the acidic products within a desired pH range. In a preferred embodiment, the second bioerodible polymer comprises polypropylene fumarate (PPF), which is cross-linked, desirably by a vinyl monomer such as vinyl pyrrolidone (VP) to form the biopolymeric scaffolding which provides the semi-IPN with dimensional and geometric stability.
摘要:
A bioerodible polymeric material, and in particular a semi-interpenetrating network (“semi-IPN”) alloy, is disclosed. A beneficial end use of this material is in the form of internal fixation devices (IFDs) (such as bone supports, plates, and pins) and as cured bone cements for bone repair. A multi-part bioerodible cement system, which, upon mixing of the system parts, forms a cured bioerodible cement, includes, in one part, a first bioerodible polymer (e.g., PLGA) capable of producing acidic products upon hydrolytic degradation, and, in another part, a second bioerodible scaffolding polymer (e.g., PPF) which upon crosslinking provides a biopolymeric scaffolding or internal reinforcement for the cured cement. In another aspect, a bone cement system of the invention includes a bioerodible scaffolding polymer (such as PPF), which when polymerized provides a hardened bone cement, the cement system further including a gas generating agent in stabilized form for providing the cured bone cement with pores for facilitating inward cell migration.
摘要:
The invention is based on the discovery of a method for scalable, continuous flow production of a nucleic acid-containing microparticle that maintains the structural integrity of the associated nucleic acid and results in a microparticle having a purity suitable for introduction into an animal (e.g., human) host. Microparticles prepared according to the continuous flow processes described herein can be used for delivery of a nucleic acid for gene therapy, antisense therapy, vaccination, treatment of autoimmune disease, and either specific or non-specific modulation of an immune response (e.g., via cytokine regulation). The microparticles can additionally be used to deliver nucleic acid encoding a protein or peptide useful in any type of therapy.