Some embodiments are directed to methods for serially expanding an artificial heart valve within a pediatric patient. For example, the artificial heart valve can be implanted into the pediatric patient during a first procedure, and then expanded during a second procedure to accommodate for the pediatric patient's growth. Some embodiments include introducing an expander into the implanted valve when the frame is expanded to a first working diameter, and then actuating the expander to expand the frame to a second working diameter greater than the first working diameter, to accommodate for the pediatric patient's growth.

Medical material and a method for preparing a biological tissue for a medical application are provided. The material is useful as a sealing element in a heart valve prosthesis. A method includes decellularizing the biological tissue by decellularizing solution to obtain an acellular extracellular matrix, solubilizing the extracellular matrix of the biological tissue, and crosslinking collagen fibers of the solubilized extracellular matrix.

Disclosed herein are methods for modifying a substrate having a hydrophobic surface. Also disclosed are modified hydrophobic substrates. The modified hydrophobic substrates and methods disclosed herein advantageously improve cell affinity and antithrombogenicity of hydrophobic surfaces.

The present disclosure relates to methods of preparing personalized blood vessels, useful for transplantation with improved host compatibility and reduced susceptibility to thrombosis. Also provided are personalized blood vessels produced by the methods and use thereof in surgery.

Disclosed are a functionalized biological matrix material, a preparation method therefor and use thereof, which belong to the technical field of medical materials. In the present invention, by means of the hybridization of a biological matrix material with 3-sulfopropyl methacrylate, the cross-linking and functionalization of the biological matrix material are achieved at the same time. A specific method comprises modifying carbon-carbon double-bond structures such as allyl, methallyl in a biological matrix material, immersing the biological matrix material in an aqueous solution containing 3-sulfopropyl methacrylate, and finally performing cross-linking and functionalization on the biological matrix material by means of radical polymerization, and using the biological matrix material to prepare materials such as valves. The present invention achieves multi-site and long-range cross-linking of a biological matrix material by means of a polymer network, and at the same time introduces corresponding functional functional groups so as to achieve functionalization of the biological matrix material.

Current approaches in small diameter vascular grafts for coronary artery bypass surgeries fail to address physiological variations along the graft that contribute to thrombus formation and ultimately graft failure. An interlayer drug delivery system can sustain delivery of heparin through the graft with a high degree of temporal and spatial control. A heparin-loaded gelatin methacrylate interlayer sits between a biohybrid composed of decellularized bovine pericardium and poly(propylene fumarate) and UV crosslinking is controlled via 3D printed shadow masks. The masks enable control of the resultant gelMA crosslinking and properties by modulating the incident light intensity on the graft. High doses of heparin have detrimental effects on endothelial cell function. When exposed to heparin in a slower, more sustained manner consistent with the masks, endothelial cells behave similarly to untreated cells. Slower release profiles cause significantly more release of tissue factor pathway inhibitor, an anticoagulant, than a faster release profile.

Provided is a method for producing a three-dimensional tissue having a vascular system structure, said method comprising: (a) a step for forming a vascular system structure template using a gel; (b) a step for forming a three-dimensional tissue in the vicinity of the template; (c) a step for dissolving the template using a cationic solution; and (d) a step for seeding vascular endothelial cells and/or lymphatic vessel endothelial cells in a void remaining after the dissolution of the template. Also provided is a method for producing a three-dimensional tissue having a vascular system structure, said method comprising: (i) a step for forming a vascular system structure template using a gel; (ii) a step for seeding vascular endothelial cells and/or lymphatic vessel endothelial cells on the template; (iii) a step for forming a three-dimensional tissue in the vicinity of the cells seeded above; and (iv) a step for dissolving the template using a cationic solution. Also provided is a three-dimensional tissue comprising a gel which has a vascular system structure.

This disclosure describes decellularized, biologically-engineered tubular grafts and methods of making and using such decellularized, biologically-engineered tubular grafts.

The present disclosure provides synthetic collagen and methods of making and using synthetic collagen that include a synthetic collagen that facilitates wound closure comprising an isolated and purified triple helical backbone protein that facilitates wound closure comprising one or more alteration in a triple helical backbone protein sequence, that stabilize the isolated and purified triple helical backbone protein and does not disrupt an additional collagen ligand interaction; and one or more integrin binding motifs, wherein the isolated and purified triple helical backbone protein facilitates wound closure.

The invention is directed to biomedical polyurethanes. The invention is particularly directed to biomedical polyurethanes with improved biodegradability and to an improved preparation of the biomedical polyurethanes. In particular the present invention provides a biomedical polyurethane having the formula (A-B-C-B).sub.n, wherein A denotes a polyol, B denotes a diisocyanate moiety, C denotes a diol component and n denotes the number of recurring units, and wherein the B-C-B segment is bioresorbable.