摘要:
An electrical process for enhancing and/or controlling transport of molecules across tissue such as human and animal skin is disclosed. The process involves the use of a high voltage, short duration electrical pulses on the tissue surface to produce electroporation. Once this effect has occurred, concentration, pressure or temperature gradients, or iontopheresis can be used to move molecules across the tissue. The process can be repeatedly applied without producing undesirable tissue damage or can be used to purposely cause highly limited tissue damage for the purpose of providing a desired, relatively long term molecular transport pathway. The occurrence of the electroporation effect can be detected by monitoring the tissue for a reversible electrical breakdown, which, along with an enhanced tissue permeability, is the characteristic effect of electroporation.
摘要:
A magnetically responsive composition for the modulated, sustained administration of a biologically active substance, the composition being in the form of a body sized and shaped for placement in the environment of use, the environment including an aqueous fluid, the body comprising, in admixture, a first phase comprising a biocompatible, plastically deformable, polymeric matrix, the polymeric matrix being insoluble in the environment of use, a second phase having a biologically active substance distributed throughout the matrix to be released to the aqueous fluid outside the matrix, and a third phase comprising a magnetically responsive substance encapsulated within the matrix so that, upon exposure of the body to an oscillating magnetic field, the rate of release of the biologically active substance to the aqueous fluid is increased.
摘要:
Heparinase is produced by growing the bacterium, Flavobacterium heparinum in an improved defined medium consisting of a carbon source, two or more amino acids and several salts in the absence of protein. The carbon source concentration is specifically kept below a certain level to promote improved heparinase production. The sulfate source concentration is also specifically kept below a certain level to promote improved heparinase synthesis. Heparinase can be produced in this medium with or without the addition of an inducer compound.
摘要:
Delivery systems manufactured in the form of polymeric compositions for the controlled delivery of macromolecules to environments of use are disclosed. The systems are characterized as two-phase compositions comprising a phase formed of an insoluble polymeric matrix having limited water sorptivity containing in admixture therein an interpenetrating phase formed of a particulate hydrophilic water swellable, biologically active macromolecular material.
摘要:
Delivery systems manufactured in the form of polymeric compositions for the controlled delivery of macromolecules to environments of use are disclosed. The systems are characterized as two-phase compositions comprising a phase formed of an insoluble polymeric matrix having limited water sorptivity containing in admixture therein an interpenetrating phase formed of a particulate hydrophilic water swellable, biologically active macromolecular material.
摘要:
A cell delivery device is prepared comprising a controllable degradable gel phase, meshed within a polymer substrate for use in tissue-engineering. The gel phase comprises a degradable, natural or synthetic polymer, and includes a suspension of living cells. The polymer substrate comprises a biocompatible, degradable polymer, and may be synthetic or natural. Degradation of the gel phase may be controlled by enzyme activity or adjustment of gel phase physical properties. In one embodiment, the gel phase contains an enzyme and/or enzyme inhibitor to control degradation of the gel phase. The device is useful in tissue replacement and repair, and more particularly, in the repair of cartilage tissue.
摘要:
A method and apparatus for reducing the levels of low density lipoproteins (LDL) in blood is disclosed. The LDL is contacted with an enzyme which modifies it in a manner such that the LDL is rapidly removed endogenously by the patients' own metabolic processes. The enzyme may be introduced into the patient by injection, transdermal transport, nasal insufflation and ingestion. Additionally, the enzyme may be contained in a reactor for both in vivo and extracorporeal use.
摘要:
A therapeutically effective amount of soluble phospholipase A.sub.2 is administered into a subject for lowering the low density lipoproteins ("LDL") in the blood. Phospholipase A.sub.2 modifies the plasma LDL by hydrolyzing the phospholipids present in LDL. As a result, the modified LDL is rapidly removed from the bloodstream by the catabolic processes.
摘要:
The use of electroactive materials having regions of high electron density as contrast agents in magnetic resonance imaging is described. The electroactive materials may be electroactive polymers, inorganic clusters, carbon clusters, molecules that inherently exhibit electron donor-acceptor behavior having regions or moieties of high electron density, or any combination of the abovementioned contrast agents. The contrast agents of the invention decrease relaxation times of water when introduced into a subject for magnetic resonance imaging. It is particularly preferred that the contrast agents be introduced in the form of a colloidal suspension.
摘要:
Compositions, methods and systems are provided for the stimulation of biological activities within bone marrow stromal cells by applying electromagnetic stimulation to an electroactive material, wherein the electromagnetic stimulation is coupled to the electromagnetic material. In general the present invention involves attaching or associating the desired bone marrow stromal cells to or with a surface comprising an electroactive material, and applying electromagnetic radiation directly to the desired area. In preferred embodiments, the stimulation of biological activities within bone marrow stromal cells results from inducing one or more activities including, but not limited to, gene expression, cell growth, cell differentiation, signal transduction, membrane permeability, cell division and cell signalling. In particularly preferred embodiments, the present invention stimulates bone cell regeneration. In exemplary embodiments, the electroactive materials used in the present invention are either two-dimensional substrates such as thin films having at least one surface of an electroactive material, or in alternative embodiments, the electroactive materials are three-dimensional substrates comprising a matrix having at least one surface of an electroactive material.