Abstract: The invention relates to a method for obtaining viruses from a liquid viral suspension, according to which: the viral suspension is subjected to density gradient ultracentrifugation, the ultracentrifugation is carried out continuously, and the density gradient is a discontinuous gradient comprising at least 2 steps.

Abstract: The invention relates to a method for obtaining viruses from a liquid viral suspension, according to which: the viral suspension is subjected to density gradient ultracentrifugation, the ultracentrifugation is carried out continuously, and the density gradient is a discontinuous gradient comprising at least 2 steps.

Abstract: The present invention relates to a biocompatible collagenous material which is non-toxic and biodegradable in less than one month, preferably in less than one week. This material comprises collagen and at least one hydrophilic macromolecular additive which is chemically non-reactive towards the collagen, with the collagen having at least partially lost its helical structure and being crosslinked. The invention also relates to a process for obtaining such a material. The collagenous material according to the invention is used, in particular, for preventing post-operative adhesions.

Abstract: The present invention relates to a biocompatible collagenous material which is non-toxic and biodegradable in less than one month, preferably in less than one week. This material comprises collagen and at least one hydrophilic macromolecular additive which is chemically non-reactive towards the collagen, with the collagen having at least partially lost its helical structure and being crosslinked.

Abstract: A biocompatible, bioresorbable and nontoxic adhesive composition for surgical and/or therapeutic use, especially for the bonding of biological tissues to one another or to an implanted biomaterial, is provided which comprises at least one biodegradable macromolecular polyaldehyde of natural origin in aqueous solution and a collagen-based component dissolved in aqueous medium. A process for preparing this composition is also provided wherein these aqueous components are mixed together (e.g., at neutral, physiological pH) to give a gel which is rapidly applied to tissues and/or biomaterial to achieve binding. The present invention is advantageous in that it provides biodegradable macromolecular polyaldehydes with adhesive properties and the ability to be extremely well tolerated by the recipient while retaining their adhesive properties during their retention in the body.

Abstract: Biomaterial based on collagen comprises, intimately associated, a support forming a dermal substitute, said support comprising a layer based on type IV collagen and an epidermal epithelium having differentiated cells obtained by growing epidermal cells on said support.

Abstract: The invention relates to a biocompatible, bioresorbable and non-toxic adhesive composition for surgical use, for the bonding, in particular, of biological tissues to one another or in an implanted biomaterial, characterized in that it comprises a reactive acidic solution of non-crosslinked and potentially crosslinkable collagen or gelatin modified by oxidative cleavage, at a concentration which is preferably between approximately 5 and 30 by weight. It also relates to reactive acidic solutions and powders based on non-crosslinked collagen or gelatin modified by oxidative cleavage which are used as intermediate products in the preparation of the above-mentioned composition, and to the process for their preparation. It also relates to adhesive kits which comprise, on the one hand, the above-mentioned reactive acidic solution and, on the other hand, a neutralizing solution and which are intended for extemporaneous mixing.

Abstract: Human or animal placenta is subjected to moderate enzymatic digestion, in particular with pepsin at an acid pH, then, after separation of the residual tissue the impurities are separated at a moderately acid pH, the collagen is precipitated at a neutral pH, redissolved and the residual impurities precipitated at an acid pH. The collagen obtained can be brought back to a neutral pH and dried in the form of fibres. Completely transparent, physiological and hemocompatible gels and solutions can be prepared. Applications for the fabrication of contact lenses and implants.

Abstract: A porous mineral support such as a porous mineral oxide coated with an aminated polysaccharide polymer has cationic characteristics and is capable of reversibly fixing thereto biological macromolecules. This material is employed in the separation and purification of said biologic macromolecules.

Abstract: A patch for visceral surgery is made from a biomaterial consisting of two layers of collagen superimposed and closely combined, namely a porous adhesive layer of fibrous collagen and a film of collagen and/or gelatin.

Abstract: Collagen is submitted to a controlled oxidation by treatment with a solution of periodic acid or of a periodate, notably of sodium. Application to gels, implants, lenses, films, spheres, etc., of collagen.

Abstract: The process comprises subjecting the hemolyzed blood to a clarification step at a pH of between 4 and 6 in the presence of less than 15% of alcohol, then, after concentration, effecting a chromatography by exchange of anions so as to separate the hemoglobin, the albumin being thereafter eluted. The hemoglobin and the globulins may then be separated out by precipitation with 25% alcohol at a pH of 7. The proteins obtained are in the native state.

Abstract: The plasma proteins contained in a plasma solution thereof are chromatographically fractioned, e.g., to obtain a high purity therapeutic grade albumin product, by successively contacting said plasma solution with at least one anion exchanger and at least one cation exchanger in fixed bed chromatography columns, the contact and exchange medium of chromatography therein also comprising a plurality of at least partially hydrophobic support particulates and a plurality of hydrophilic ion exchanger support particulates.

Abstract: A porous mineral support such as a porous mineral oxide coated with an aminated polysaccharide polymer has cationic characteristics and is capable of reversibly fixing thereto biological macromolecules. This material is employed in the separation and purification of said biologic maromolecules.

Abstract: A process for preparing a porous solid material for use in a chromatography column and which is capable of fixing reversibly biological macromolecules comprises coating a porous inorganic support with a polysaccharide polymer having .alpha.-glycol groups which undergo oxidative scission, subjecting the polysaccharide polymer to an oxidative scission reaction, reacting the resulting oxidized polysaccharide polymer with an amino molecule or macromolecule having the formula R'--NH.sub.2 to produce a polysacchride polymer having the formula R.sub.4 --CH.dbd.N--R' and reducing the imine bond in said immediately above defined polysaccharide polymer to a stable amine bond.