摘要:
Composite materials are disclosed which are formed by contacting collagen with a mucopolysaccharide and subsequently covalently crosslinking the resultant polymer. These composite materials have a balance of mechanical, chemical and physiological properties which make them useful in surgical sutures and prostheses of controlled biodegradability (resorption) and controlled ability to prevent development of a foreign body reaction, and many are also useful in applications in which blood compatibility is required.
摘要:
A multilayer membrane, which is useful as synthetic skin, is disclosed herein. A first layer is formed from a material which does not provoke an immune response and which is also insoluble and nondegradable in the presence of body fluids and/or body enzymes. Preferred materials for the first layer are crosslinked composites of collagen and a mucopolysaccharide. A second layer is formed from a nontoxic material which controls the moisture flux of the overall membrane to about 0.1 to 1 mg./cm.sup.2 /hr. Suitable materials for the second layer include synthetic polymers such as silicone resins, polyacrylate or polymethacrylate esters or their copolymers, and polyurethanes.
摘要:
A method for preserving the porosity of porous materials is disclosed. In this method, the porous material is subjected to elevated temperature and vacuum conditions to thereby produce a dimensionally-stable, non-collapsible porous material.
摘要:
This invention relates to the introduction of viable cells into a fibrous lattice by surgical, force-utilizing, or other manipulative techniques, all of which are referred to herein as "seeding." One embodiment comprises an autografting technique which involves intact tissue. Other embodiments which involve the distribution of an aqueous suspension of cells comprise centrifugal, spraying, pipetting and syringe emplacement. Each cell that survives the seeding process may reproduce into a colony of cells which grow until they reach confluence, thereby creating a uniform layer or volume of tissue. By proper placement of cells capable of generating such colonies, the period of recovery of a wound may be drastically reduced. In addition, research by the Applicants indicates that tissue that is regenerated using the methods of this invention to seed a lattice comprising collagen and glycosaminoglycan tends to be smoother, more uniform, less fibrotic, less scarred and more flexible than tissue that is regenerated by wound contraction or conventional autografting.
摘要:
This invention relates to the introduction of viable cells into a fibrous lattice by surgical, force-utilizing, or other manipulative techniques, all of which are referred to herein as "seeding." One embodiment comprises an autografting technique which involves intact tissue. Other embodiments which involve the distribution of an aqueous suspension of cells comprise centrifugal, spraying, pipetting and syringe emplacement. Each cell that survives the seeding process may reproduce into a colony of cells which grow until they reach confluence, thereby creating a uniform layer or volume of tissue. By proper placement of cells capable of generating such colonies, the period of recovery of a wound may be drastically reduced. In addition, research by the Applicants indicates that tissue that is regenerated using the methods of this invention to seed a lattice comprising collagen and glycosaminoglycan tends to be smoother, more uniform, less fibrotic, less scarred and more flexible than tissue that is regenerated by wound contraction or conventional autografting.
摘要:
This invention comprises the use of centrifugal force to introduce viable cells into a fibrous lattice, as well as fibrous lattices that are seeded with cells by the use of centrifugal force. A variety of fibrous lattices may be seeded by the methods of this invention, such as a highly porous lattice comprising collagen fibers crosslinked with glycosaminoglycan. Before the centrifugation, a piece of intact tissue is harvested from a donor site. It is treated with one or more substances, such as trypsin or collagenase, to dissociate cells from the tissue. The cells are then mixed with an aqueous solution to create an aqueous suspension of cells. A piece of fibrous lattice is placed within a container, referred to herein as a "bucket," that is suitable for rotation by a centrifuge. The aqueous suspension of cells is placed within the bucket, in contact with the lattice. The centrifuge is then rotated. Centrifugal force causes the cells, which are denser than the aqueous solution, to be forced into the lattice in a relatively uniform distribution. By controlling various parameters, cells can be seeded into any desired location within a lattice.
摘要:
A process for the preparation of a composite biomaterial comprising: providing a first substantially solid component comprising one or more of collagen, a glycosaminoglycan, albumin, hyaluronan, chitosan, and synthetic polypeptides comprising a portion of the polypeptide sequence of collagen, and optionally an inorganic material, said component having at least a surface portion that is porous; providing a fluid composition comprising one or more of collagen, a glycosaminoglycan, albumin, hyaluronan, chitosan, and synthetic polypeptides comprising a portion of the polypeptide sequence of collagen, and a liquid carrier, and optionally an inorganic material; contacting said fluid composition with said porous surface portion of said first component; cooling said fluid composition to a temperature at which the liquid carrier transforms into a plurality of solid crystals or particles; removing at least some of the plurality of solid crystals or particles by sublimation and/or evaporation.
摘要:
This invention relates to porous, biodegradable materials in which the pore size, biodegradation rate, and pore volume fraction are controlled and within values at which skin contraction rates around an implant-containing wound are delayed or slowed.
摘要:
A cross flow filtration molding apparatus and method are disclosed which are particularly useful for forming complicated shapes from dispersions of particles in a liquid medium. Dispersion is pumped through a mold which has porous walls and a sufficient pressure differential is applied to drive a portion of the liquid medium through the porous walls which results in deposition of particles on the walls to form a shaped article. The shaped article may inherently have sufficient structural integrity, or it may be post-treated to provide additional structural integrity.
摘要:
This invention relates to highly porous scaffolding and methods of producing the same. Specifically, the scaffolding comprises a pore volume fraction of no less than 80% (v/v) of the total volume of the scaffold and interconnecting pores forming channels in the scaffold.