1204 results about "Poly l lactic acid" patented technology

This invention provides compositions and methods for producing a medical device coated with a matrix and an antibody which reacts with an endothelial cell antigen. The matrix coating the medical device may be composed of synthetic material, such as polyurethane, poly-L-lactic acid, cellulose ester or polyethylene glycol. In another embodiment, the matrix is composed of naturally occurring materials, such as collagen, fibrin, elastin, amorphous carbon. In a third embodiment, the matrix may be composed of fullerenes. The fullerenes range from about C60 to about C100. The medical device may be a stent or a synthetic graft. The antibodies promote adherence of endothelial cells on the medical device. The antibodies may be mixed with the matrix or covalently tethered through a linker molecule to the matrix. Following adherence to the medical device, the endothelial cells differentiate and proliferate on the medical device. The antibodies may be different types of monoclonal antibodies. Methods of preparing such composition and methods of treating a mammal with atherosclerosis or other types of vessel obstruction are disclosed. By facilitating adherence of endothelial cells to the surface of the medical device, the methods and compositions of this invention will decrease the incidence of restenosis as well as other thromboembolic complications resulting from implantation of medical devices.

Toughened polyoxymethylene-poly(lactic acid) resin compositions comprising polyoxymethylene, poly(lactic acid), and an impact modifier comprising an ethylene copolymer impact modifier made from monomers (a) ethylene; (b) one or more olefins of the formula CH₂═C(R¹)CO₂R², where R¹ is hydrogen or an alkyl group with 2-8 carbon atoms and R² is an alkyl group with 1-8 carbon atoms, such as methyl, ethyl, or butyl; and (c) one or more olefins of the formula CH₂═C(R³)CO₂R⁴, where R³ is hydrogen or an alkyl group with 1-6 carbon atoms, such as methyl, and R⁴ is glycidyl. The ethylene copolymer impact modifier may further be made from carbon monoxide monomers. The compositions may further comprise one or more ethylene/acrylate and/or ethylene/vinyl ester polymers, ionomers, and cationic grafting agents.

A new embolic agent, bioabsorbable polymeric material (BPM) is incorporated to a Guglielmi detachable coil (GDC) to improve long-term anatomic results in the endovascular treatment of intracranial aneurysms. The embolic agent, comprised at least in part of at least one biocompatible and bioabsorbable polymer and growth factors, is carried by hybrid bioactive coils and is used to accelerate histopathologic transformation of unorganized clot into fibrous connective tissue in experimental aneurysms. An endovascular cellular manipulation and inflammatory response are elicited from implantation in a vascular compartment or any intraluminal location. Thrombogenicity of the biocompatible and bioabsorbable polymer is controlled by the composition of the polymer. The coil further is comprised at least in part of a growth factor or more particularly a vascular endothelial growth factor, a basic fibroblast growth factor or other growth factors. The biocompatible and bioabsorbable polymer is in the illustrated embodiment at least one polymer selected from the group consisting of polyglycolic acid, poly~glycolic acid/poly-L-lactic acid copolymers, polycaprolactive, polyhydroxybutyrate/hydroxyvalerate copolymers, poly-L-lactide. Polydioxanone, polycarbonates, and polyanhydrides.

A displacement sensor having a rectangular shaped elastic member. A piezoelectric element is attached to a first main face of the elastic member. The piezoelectric element has a rectangular-shaped piezoelectric sheet and electrodes on both main faces of the piezoelectric sheet. The piezoelectric sheet is made of poly-L-lactic acid and is at least uniaxially-stretched. The piezoelectric element is attached so that the uniaxial-stretching direction of the piezoelectric sheet is 45° relative to a long-side direction of the elastic member. When the elastic member is bent along the long-side direction, the piezoelectric sheet is stretched along the long-side direction, and the piezoelectric element generates voltage of predetermined level.

A touch panel capable of detecting a pen and a finger, capable of corresponding to multi-touch, capable of detecting pressing force, and capable of reducing the use amount of a transparent electrode as much as possible. The touch panel has a piezoelectric sheet of poly-L-lactic acid having a predetermined stretching axial direction, electrodes that are opposed to each other and formed on the piezoelectric sheet do not cover the entire surface of the piezoelectric sheet and are formed so that they are discretely distributed in plural positions. The piezoelectric sheet is brought into the condition that tension is imparted in directions not coincident with the stretching axial direction.

Absorbable stents and absorbable stent coatings have been developed with improved properties. These devices preferably comprise biocompatible copolymers or homopolymers of 4-hydroxybutyrate, and optionally poly-L-lactic acid and other absorbable polymers and additives. Compositions of these materials can be used to make absorbable stents that provide advantageous radial strengths, resistance to recoil and creep, can be plastically expanded on a balloon catheter, and can be deployed rapidly in vivo. Stent coatings derived from these materials provide biocompatible, uniform coatings that are ductile, and can be expanded without the coating cracking and/or delaminating and can be used as a coating matrix for drug incorporation.

A resin composition containing a crystal structure of poly(lactic acid), which is obtained by melt-kneading 30 to 99 mass % of poly(lactic acid) and 70 to 1 mass % of a copolymer having a functional group reactive with the poly(lactic acid); a method of producing the same; and moldings.

The invention relates to a PLA/PLGA shell-core microsphere prepared by solid-in-oil-in-water in the technical field of pharmacy and a preparation method thereof. The microsphere comprises 0.01 to 50 percent of medicine, 20 to 99.99 percent of polylactic acid and/or polylactic acid-glycolic acid, or/and 0 to 30 percent of pharmaceutical excipient (weight percentage). The method comprises the steps of: adding medicine particles into a PLA and/or PLGA organic solution to be emulsified, then selecting a hydrophilic organic solvent to re-emulsify to form unhardened balls, finally hardening in another large oil phase, removing the organic solvent and collecting micropheres. The method overcomes the disadvantages of low envelope rate of the prior W/O and W/O/W, serious burst release of S/O/O, and environmental pollution, controls the grain diameter of the microsphere according to the need, does not pollute the environment, and can be applied to the preparation of slow release or controlled release microspheres of various medicines and adjuvants of vaccines.

There are provided a resin composition comprising a polylactic acid which (i) comprises a poly-L-lactic acid (component B-1) and a poly-D-lactic acid (component B-4), (ii) has a weight ratio of the component B-1 to the component B-4 (component B-1/component B-4) of 10/90 to 90/10, and (iii) shows a proportion of melt peaks at 195° C. or higher to all melt peaks in a temperature rising process in measurement by a differential scanning calorimeter (DSC) of at least 20%; a molded article of the resin composition; and methods for producing the resin composition and the molded article.

Biodegradable polymeric microparticle compositions containing one or more active agents, especially those useful for treating or preventing or one or more diseases or disorders of the eye, and methods of making and using thereof, are described. The microsphere compositions release an effective amount of the one or more active agents for a period greater than 14 days in vivo, preferably greater than 60 days in vivo, more preferably up to 73 days in vivo, more preferably greater than 90 days in vivo, even more preferably over 100 days in vivo, and most preferably greater than 107 days in vivo. In a preferred embodiment, the microparticle compositions contain one or more active agents useful for managing elevated intraocular pressure (TOP) in the eye. In one embodiment, the microspheres are formed from polylactide-co-glycolide (“PLGA”); in another embodiment, the microspheres are formed from a blend PLGA and poly lactic acid (“PLA”). Relatively hydrophilic, and preferably carboxylated, polymeric materials such as PLGA are used for a drug such as timolol maleate, which is relatively water soluble, to increase drug loading. Higher molecular weight polymers, as well as the ratio of LA (which has a longer degradation time, up to one to two years) to GA (which has a short degradation time, as short as a few days to a week), are used to provide release over a longer period of time. The combination of drug loading and release rate, as well as the minimization of initial burst release, result in prolonged release of a higher amount of drug.

The invention discloses slow-release microspheres coated with rivastigmine tartrate/rivastigmine for PLGA/PLA injection and a preparation method thereof. The slow-release microspheres mainly comprise rivastigmine tartrate/rivastigmine and PLGA and PLA serving as biodegradable polymer medicinal materials, and can be prepared by adopting a W1/O/W2 composite emulsified solvent volatilization method, an O/W emulsified solvent volatilization method, an O1/O2 emulsion drying method and a spray drying method. The grain diameter of the microspheres is less than 100 microns. The slow-release microspheres have high medicament loading amount, have no obvious burst release effect, can be continuously released for one week, one mouth or three mouths, are used for treating senile diseases such as Alzheimer's disease, Parkinson disease and the like, and can prolong the acting time of the medicament, reduce the application times and greatly improve the administration compliance of patients.

A biodegradable film formable into biodegradable bags includes the blended product of polylactic acid and a suitable biodegradable polymeric resin. The blended product includes from about 5% to about 50% by weight polylactic acid.

The invention relates to a preparation method of a porous nano-fiber tubular scaffold, which comprises the steps that (1) PLLA (Poly L Lactic Acid) and other polymers are dissolved in a solvent to get a polymer solution; (2) the polymer solution is injected into a tubular mold and rapidly placed at a low temperature for phase separation, then the polymer solution is taken out, a tubular mold housing is removed, polymer gel after the phase separation and a core mold are immersed in ice water together, then the core mold is taken out, the polymer gel is immersed in deionized ice water to exchange the solvent, and the tubular scaffold is obtained; and (3) finally, the tubular scaffold obtained is frozen and dried for 48-120 hours, and then the porous nano-fiber tubular scaffold is obtained. The preparation method is simple to operate, and requires no additional hole-foaming agent, is suitable for volume production, and is lower in preparation cost; the prepared tubular scaffold has a nano-fiber structure similar to an extracellular matrix of a human tissue, and a porous structure with the diameter and porosity capable of being adjusted, and facilitates growth of cells and reconstruction of a cambium.

An absorbable internal fixing material for bone fracture is prepared from polylactic acid (50-90 wt.%), tricalcium phosphate (1-40 wt.%) and hydroxylapatitie (1-40 wt.%) through mixing then and then hot die pressing at 80-1230 deg.C and under 0.11-25 MPa or hot extruding at 80-230 deg.c. The granulality of hydroxylapatite and tricalcium phosphate is less than 100 microns. Its advantages are high strength, high strength, high X-ray visualization and high biocompatibility.

A novel usage of poly-L-lactic acid as medical shape memory material is provided. Forming the poly-L-lactic acid to initial shape under the temperature of 190í½210íµ and pressure of 2í½10Mpa to obtain the poly-L-lactic acid with shape memory property. The present invention uses poly-L-lactic acid as medical degradable shape memory material for the first time. It can be widely applied in minor trauma invasive stent, vessel jointing, operation suture line, bone fracture fixation and other medical field.