111 results about "Intimal hyperplasia" patented technology

Stents and methods of using stents are provided. Stents of the invention provide external support structure for a blood vessel segment disposed within, wherein the stents are capable of resilient radial expansion in a manner mimicking the compliance properties of an artery. The stent may be formed of a knitted or braided mesh formed so as to provide the needed compliance properties. A venous graft with the stent and a vein segment disposed within is provided, wherein graft is capable of mimicking the compliance properties of an artery. Methods of selecting stents for downsizing and methods of using the stents of the invention in downsizing and smoothening are provided. Methods of replacing a section of an artery with a venous graft including a stent of the invention are provided. Methods of reducing intimal hyperplasia in implanted vein segment in a venous graft using stents of the invention are provided.

Compositions and methods are provided for producing a medical device such as a stent, a stent graft, a synthetic vascular graft, heart valves, coated with a biocompatible matrix which incorporates antibodies, antibody fragments, or small molecules, which recognize, bind to and/or interact with a progenitor cell surface antigen to immobilize the cells at the surface of the device. The coating on the device can also contain a compound or growth factor for promoting the progenitor endothelial cell to accelerate adherence, growth and differentiation of the bound cells into mature and functional endothelial cells on the surface of the device to prevent intimal hyperplasia. Methods for preparing such medical devices, compositions, and methods for treating a mammal with vascular disease such as restenosis, artherosclerosis or other types of vessel obstructions are disclosed.

A tubular vascular transplant (1, 1′, 1″, 1′″) serves for connecting vessels in the human body. The transplant, in particular made of expanded polytetrafluoroethylene (ePTFE), can preferably be used for an arteriovenous shunt for carrying out a dialysis. The transplant is connected by its first, proximal end to a vessel, for example an artery (2), and by its distal end to another location of the same vessel or to a different vessel, for example a vein (3). The lumen of the transplant (1, 1′, 1″, and 1′″) widens in a steadily conical manner in the region of its distal end and forms a diffuser (8) there. The cone angle (a) of the wall of the diffuser (8) with respect to the central flow direction of the blood in the transplant (1′, 1″, 1′″) is preferably 6° to 7°. In the region of the diffuser (8), preferably at least one, preferably planar, dividing wall (11, 11′, 11a, and 11b) is provided, running in the central flow direction of the blood. This makes it possible to prevent the formation of an intimal hyperplasia and a pseudointima.

A stent according to the present invention incorporates an intraluminal scaffold for initial relief of stenoses or for providing support within bodily lumens, such as blood vessels, of children and adults. The scaffold minimizes flow disturbances in a stented region of a bodily lumen by the use of a strut having a transitional lumen surface, thereby limiting the potential for the development of neointimal hyperplasia and subsequent restenosis, and lessening the potential for early and late thrombosis formation and dislodgement. Any stent for use in any application can be initially manufactured with the strut shape of the current invention. Alternatively, the shape of the struts of existing stents can be modified during a post-processing procedure after fabrication thereby making the invention applicable to all stent designs presently available.

The described invention provides pharmaceutical compositions and methods for treating or preventing vascular graft failure in a subject in need of such treatment, the method comprising administering a therapeutically effective amount of a composition comprising a polypeptide of amino acid sequence YARAAARQARAKALARQLGVAA (SEQ ID NO: 1) or a functional equivalent thereof, and a pharmaceutically acceptable carrier. The methods also are clinically useful for treating a pre-atherosclerotic intimal hyperplasia condition.

The invention discloses an expandable saccule provided with a modified coating on the surface. The expandable saccule is characterized by comprising a saccule body and the modified coating, wherein the saccule body is a high-molecular material, and the modified coating is a water-insoluble high-molecular polymer. A preparation process of the expandable saccule provided with the modified coating on the surface is characterized by comprising the following steps: a, pretreatment of the surface of the saccule body; b, preparation of a coating solution; c, surface coating; d, UV light triggered polymerization; e, pore formation by washing of a solvent; f, low-temperature drying. During use, the expandable saccule disclosed by the invention can be used for ensuring a drug to be firmly adhered and loaded on the outer surface of a coating on the periphery of the saccule body and in pores of a porous structure of the saccule body, the initial drug loaded capacity is increased and drug loss during a conveying process of the saccule is reduced as well, so that enough drug is ensured to be released to diseased regions during an expansion process of the saccule, and thus the performances of preventing and treating lesions such as restenosis and intimal hyperplasia by expanding the saccule of blood vessels can be better improved.

A stent includes a stent body of a cylindrical configuration having outer and inner surfaces, a first coated layer coating at least the outer surface, and a second coated layer coating substantially completely over the first coated layer. The first coated layer is prepared of a first composition comprising a polymer and a vascular intimal hyperplasia inhibitor (preferably argatroban) of a kind, which does not inhibit proliferation of endothelial cells, the weight compositional ratio of the polymer to the inhibitor being within the range of 8:2 to 3:7. On the other hand, the second coated layer is prepared of a polymer alone or a second composition comprising a polymer and a drug, the weight compositional ratio of the drug to 80% by weight of the polymer being less than 20% by weight.

The invention relates to a bioengineering technology, in particular to a small-caliber biotic artificial blood vessel with anti-thrombus formation and anti-intimal hyperplasia functions. Firstly, the key technology of accellular materials and natural polymer composition is used, and through multiple modes, neurotrophic factors are effectively coupled as functional modules to perform modification on blood vessel supports. Furthermore, through the strategy of constructing in body, the small-caliber engineering blood vessel modified by the neurotrophic factors is transplanted in body, the scour and the pressure of hemodynamics are overcome in body, endothelial progenitor cells in circulation are captured initiatively, the endothelial progenitor cells are further induced to differentiate into endothelial cells in situ, and the progress and the quality of endothelialization of blood vessel graft are speeded. Meanwhile, the generation of blood capillaries is promoted and nurtured, the blood vessel implants are promoted to remodel in body, therefore, the effects of anti-thrombus formation and anti-intimal hyperplasia can be effectively achieved, and the patency rate after the small-caliber biotic artificial blood vessel is transplanted is increased. Active small-caliber tissue engineering blood vessels used for coronary arterie bypass grafting, hematodialysis and cerebrovascular replacement in clinic are built.

The present invention belongs to the field of biomedical engineering, in the concrete, it relates to a photosensitive scaffold with the function of preventing and curing restenosis. The photosensitizer can be used to modify the scaffold so as to obtain photosensitive scaffold, said photosensitive scaffold is placed in the pathological lumen, and irradiated by light, so that the photosensitizer on the scaffold can be activated so as to produce photochemical reaction to form active oxygen substance, resist endometrial hyperplasia/and prevent production of scaffold restricture.

The invention relates to a degradable zinc-based micropore drug-loaded support and a preparation method thereof. The support comprises a degradable zinc-based material support matrix, uniform drug-loaded micropores are arranged on the surface of the support matrix, a therapeutic medicine coating covers the surface provided with uniform drug-loaded micropores, and the support matrix is in a cylinder net structure. The preparation method comprises the following steps: 1)processing the degradable zinc based material to the support matrix; 2)pretreating the surface of the support matrix; 3)performing electrolytic polishing processing on the support matrix; 4)performing corrosion processing on the support matrix after polishing; 5)pickling the support matrix after corrosion; and 6)coating a therapeutic medicine on the surface of the support matrix after aperture making. The support has good support performance after implantation for more than 4 months due to superior corrosion resistance of a zinc alloy matrix material, uniform micropores are distributed on the matrix surface, the therapeutic medicine layer is coated, so that medicine release can be controlled, support effect of the metal support can be fully performed, and the drug-loaded support has medical science curative effect with drug eluting support for inhibiting intimal hyperplasia to restenosis.

The invention relates to application of a novel polytetrafluoroethylene nano material in preparation of artificial blood vessels. A preparation method for the novel material comprises that self-assembling a functional multi-walled carbon nano tube (MWNT) film layer by layer on a polytetrafluoroethylene substrate. The invention also provides the application of the novel polytetrafluoroethylene (PTEF) nano material in preparation of the artificial blood vessels. The invention has the advantages that the MWNT film is obtained on the PTEF substrate pretreated by phthalic diglycol diacrylate (PDDA) through layer-by-layer self-assembly; by the simple preparation method, the performance of the substrate material can be well improved, and the self-assembled MWNT film using PTEF as the substrate is widely applied; and MWNT is combined with a PTEF blood vessel material massively used in clinic at present, so that postoperative endangium hyperplasia degree of artificial blood vessel implantation can be lightened in animal experiments, the patency rate of the blood vessels is improved, and a feasible method is provided for improving the curative effect of artificial blood vessel implanting operation in clinic.

A drug-eluting stent comprises a coated layer prepared of a composition comprising a polymer and a drug, the coated layer being a single coated layer with the composition, or comprises a first coated layer prepared of the above composition and a second coated layer with a polymer alone, the first coated layer being coated by the second coated layer. The drug is a vascular intimal hyperplasia inhibitor which does not inhibit proliferation of endothelial cells, and the composition substantially excludes a lipid-soluble low-molecular compound. The polymer in the first layer is a copolymer of lactic acid (monomer A) and a terminal hydroxy straight alkyl carboxylic acid having 3 to 8 carbon atoms, and, if the second coated layer is formed, the polymer in the second coated layer is a poly(lactic acid), a poly(glycolic acid), or a poly(lactic acid-co-glycolic acid).

The invention relates to a vascular stent with a degradable drug-loaded coating and a preparation method thereof. The vascular stent includes a stent body, and also includes a calcium-phosphorus transition layer and a regenerated drug-loaded coating. The calcium-phosphorus transition layer is located on the surface of the stent body, the regenerated drug-loaded coating is located on the surface of the calcium-phosphorus transition layer, and the regenerated drug-loaded coating and the calcium-phosphorus transition layer have same ingredients and fix drugs. The contribution of the invention lies in that the vascular stent can fix drugs in a biodegradable coating without using polymer, and can control drug release by adjusting the regenerated drug-loaded coating. The experimental result shows that the polymer-free degradable drug-loaded coating can effectively inhibit vascular intimal hyperplasia and avoids the occurrence of restenosis.

Methods are described for dilating biological conduits by removing elastin and remodeling collagens in the wall of the conduit. Methods include the use of agents that increase the release of endogenous elastase and collagenase in the wall of the conduit, either by cells that are normally present in the wall of the conduit or by inflammatory cells that are attracted to the conduit, thereby providing additional conduit dilation. Methods also include the use of agents that increase conduit wall permeability and expose elastin and collagen fibers. Methods also include removing components of the extracellular matrix of arteries and veins leading to an inhibition of intimal hyperplasia in the wall of the vessels by decreasing biomechanical stimuli directed toward the cells in the wall of the vessel. Methods further include the use of agent that degrade micro fibers, in addition to elastin, in order to decrease the resynthesis of elastin. Methods also include the use of agent that stabilize the diameter of aneurysmal arteries by blocking cell surface receptors in the wall of the aneurysmal artery that are important in the recruitment of inflammatory cells.

The invention relates to a novel polytetrafluoroethene (PTEF) nanocrystallization material and a preparation method thereof. According to the preparation method for the novel material, functional multiwalled carbon nanotube (MENT) thin films are self-assembled on PTEF substrates layer by layer. The invention also provides a novel PTEF nanocrystallization artificial blood vessel and a preparation method thereof. The preparation method has the advantages that the MENT thin films are self-assembled on the PTEF substrates which are pre-treated by phthalic diglycol diacrylate (PDDA), so that the performance of the substrate materials can be improved well by the simple and convenient preparation method, and the MENT thin films which are self-assembled layer by layer by taking PTEF as the substrates can be widely applied; and the MENTs can be combined with PTEF blood vessel materials which are clinically used on large scale at present, the degree of intimal hyperplasia of the blood vessels, which is caused after implantation of artificial blood vessels can be reduced, the patency rate of the blood vessels is improved, and a feasible method is provided for improving the curative effect of the implantation operation of the artificial blood vessels clinically.

The invention relates to the field of medical equipment and particularly relates to a bracket type vascular anastomosis device. The bracket type vascular anastomosis device comprises a film laminating bracket; the film laminating bracket comprises an inner-layer laminating film, a metal bracket and an outer-layer laminating film; the whole body of the metal bracket is cylindrical; the inner-layer laminating film and the outer-layer laminating film are lined on an inner side and an outer side of the metal bracket respectively; the bracket type vascular anastomosis device further comprises a conveyor and the conveyor comprises a balloon, a connecting hose and a connector, which are communicated in sequence; the metal bracket is formed by knitting a cobalt-chromium alloy wire or a NiTi shape memory alloy wire; the balloon is a non-compliance balloon; the balloon is arranged in the film laminating bracket. The bracket type vascular anastomosis device is suitable for carrying out vascular anastomosis on deep tissues with relatively narrow spaces; the vascular anastomosis time can be shortened; vascular intimal hyperplasia can be reduced to the greatest extent and a narrow anastomosis hole is avoided; after the anastomosis, a blood vessel can be retracted and relaxed in a certain extent along blood pressure and physiological demands are met; the blood vessel can be prevented from slipping off from the film laminating bracket and the bracket type vascular anastomosis device is very reliable.

The invention discloses a microcrystalline sacculus of a reticular structure. The sacculus is prepared from non-water-soluble polymer materials by controlling the technological conditions in a two-way stretching and blow molding mode, and molecular chains of the sacculus are distributed in a mesh shape and contain a great number of microcrystalline structures. A preparation process of the microcrystalline sacculus of the reticular structure includes the following steps of 1, parison drawing, 2, parison preheating, 3, stretching and blow molding of the sacculus, 4, high-temperature high-pressure sizing and 5, microcrystallization treatment. The sacculus prepared through the process has the advantages of being high in compression strength, high in light transmittance performance, low in shrinking percentage, good in size stability and the like, a microcosmic microcosmic of the sacculus is of a reticular microcrystalline structure, and the microcrystalline sacculus can be used for treating hemadostenosis, intimal hyperplasia and other diseases.

An intravascular filter comprises a plurality of first connecting rods, a plurality of second connecting rods and a plurality of support rods. The first connecting rods are gathered at one end to forma first filter screen of a cage structure. The second connecting rods are gathered at the other end to form a second filter screen of a cage structure. The support rods are connected with the non-gathering ends of the first connecting rods and the second connecting rods respectively. The cross section of each support rod is designed in the shape of a blade, so that neovascular intimae can be cutduring recovery of the intravascular filter. The intravascular filter has the advantages that the support rods are blade-shaped, and the intravascular filter can cut the neovascular intimae on the inner walls of blood vessels during recovery, so that direct tearing damage to the vascular walls is avoided, and the recovery failure rate is greatly decreased; the width of each support rod is smallerthan the thickness of the vascular wall, and the contact areas between the filter and the inner walls of the blood vessels are reduced to the greatest extent while the supporting force is ensured, sothat endothelialization is slowed down, and intimal hyperplasia is relieved; through bidirectionally-arranged recovery hooks, the recovery success rate can be increased.

The invention provides a drug eluting stent which comprises a stent and a drug coating covering the surface of the stent. The drug coating comprises a drug and a drug carrier, wherein the drug is astragalus polysaccharide, astragaloside and bilobalide in weight ratio of (1-2):1:(1-2). The invention further provides a preparation method of the drug eluting stent. The drug coating of the drug eluting stent provided by the invention is uniform in thickness, smooth in surface, free from cracks and falling. In vitro degradation experiment shows that the drug stent coating material is corroded and degraded on the surface to release the drug without falling. The drug in the drug coating of the drug eluting stent provided by the invention is slowly released and has the effect of inhibiting intimal hyperplasia, so that occurrence of restenosis is reduced.