Abstract: The invention relates to oral pharmaceutical compositions for the prevention and/or the treatment of viral diseases. This invention also addresses methods of prevention and/or treatment of these viral diseases, using these oral compositions. One of the main problems considered in the present invention is to enhance the efficiency of anti-viral treatments, especially against Hepatitis C virus by means of ribavirin, for example in combination with interferon. The oral ribavirin antiviral composition according to the invention increases the bio-absorption time of ribavirin, and thus improves the treatment of patients. Said composition comprises at least one modified release form of ribavirin, the bio-absorption time BAT of which is greater than the bio-absorption time BAT* of a reference* immediate release form of ribavirin administered at the same dose; BAT being preferably comprised between 2 and 15 h and more preferably between 4 and 12 h. Said composition is a reservoir type form or a matrix type form.

Abstract: The invention relates to novel materials based on biodegradable polyamino acids that are useful for vectorizing active principle/s (AP). The aim of the invention is to supply a new polymeric raw material that is used for vectorizing AP and optimally fulfills all requirements concerning biocompatibility, biodegradability, the ability to be easily associated with numerous active principles or solubilize said active principles and to release the active principles in vivo. Said polymers can also be readily and economically transformed into particles vectorizing active principles according to the grafting rate of the hydrophobic groups, said particles being able to form stable aqueous colloidal suspensions.

Abstract: A suspension of vector particles (PV) based on polyamino acids and have a mean hydrodynamic diameter between 30 and 120 nm, and an insulin load factor of from 5 to 25% of associated insulin volume relative to the polyamino acid volume forming the vector particles. The polyamino acids are double-block polymers containing hydrophilic and hydrophobic monomers. The suspension may be prepared by copolymerizing N-carboxy anhydrides of hydrophobic monomers and precursors of hydrophilic monomers, in the presence of N-methyl pyrrolidone and methanol. The copolymer is optionally neutralized, subjected to dialysis, concentrated and water is eliminated to produce a solid powder, which can be suspended in a liquid to produce the colloidal suspension. Active principles such as insulin or vaccines are associated with the carrier particles to prepare special pharmaceutical products.

Abstract: The field of the invention is that of oral pharmaceutical medicinal products or compositions, more particularly of the type of those comprising one or more active principles. The aim of the invention is to provide an improved oral medicinal product that can be administered in one or more daily doses, with modified release of active principle (in particular an active principle), for improving the prophylactic and therapeutic efficacy of such a medicinal product. This aim is achieved by means of the multimicrocapsular oral pharmaceutical form according to the invention in which the release of the AP is controlled by means of a double mechanism of triggering the release: “time triggering” and “pH triggering”. This medicinal product comprises microcapsules with modified release of active principle, each containing a core comprising the active principle and one or more swelling agents, and at least one coating making possible the modified release of the active principle.

Abstract: The invention relates to novel collagen peptides that are modified by grafting free or substitued thiol functions carried by mercaptoamine radicals. The aim of the invention is to provide thiol collagens that can be cross-linked in a sufficient and controlled manner by forming S—S bridges and which are biocompatible. This is achieved by means of the inventive thiol collagens which are characterized in that the mercaptoamine radicals are identical to or different from each other and are exclusively grafted on the aspartic and glutamic acids of the collagen chain by amide bonds. The invention also relates to a method for the production of said thiol and cross-linkable collagens. The novel modified cross-linkable and/or cross-linked collagens can be used as biomaterials.

Abstract: The aim of the invention is to provide a modified collagen peptide for preventing post-operative adhesions that is non-toxic, economic, in addition to being easy to obtain, sterilize, manipulate and implement, having controlled biodegradability and presenting a sufficiently strong initial mechanical resistance in situ (cohesion). This is achieved in the case of the modified collagen peptide for preventing post-operative adhesions according to the invention which is characterized in that it comprises at least one collagen peptide that is modified by grafting thiol functions that are free or substituted, cross-linkable and/or at least partly cross-linked, whereby the thiol functions are provided by mercaptoamine radicals that are exclusively grafted on the aspartic and glutamic acids of the collagen chains by means of amide bonds. The modified collagen peptide can exist in the form of a homogeneous or composite film, as a gel or in as a liquid which can be applied and cross-linked per se as on in vivo tissue.

Abstract: The invention concerns delivery particles (DP's) for active principles (AP's) based on linear amphiphilic polyamino-acids (PAA's), with &agr;-peptide chains, capable of being spontaneously formed by contacting PAA's with a liquid medium, preferably with water, wherein the hydrophile part of the PAA's is solubilized more than the hydrophobic parts of said PAA's, such that the latter precipitate while being organised in discrete supra-molecular arrangements, of average size ranging between 0.01 and 20 &mgr;m, capable of combining with at least an AP and releasing the latter in vivo, in prolonged and controlled manner.

Abstract: Novel spiropyran compounds, particularly with photochromic properties, are disclosed, as well as photochromic compositions and ophthalmic articles containing said compounds. The photochromes have been designed so as to have a high colorability, a high sensitivity to activating radiation breaking the pyran ring, to be entirely or practically free from coloration in a non activated non exposed state, to have an intense coloration following activation and a high coverage of the visible spectrum in combination with at least one other photochrome, and to have high rates of coloration/decoloration. The spiropyrans are easily produced and photochemically stable, and are, e.g., of formula (i), wherein L=(a); (b).

Abstract: The invention relates to vectors for delivering medicinal, nutritional, plant-protection or cosmetic active principles, these delivery particles being of small, controllable and adjustable particle size, which protect the active principle, and being biocompatible, biodegradable, non-immunogenic, stable and free of solvent. The particles do not denature the active principle and allow the active principle to be released. The microparticles of the invention are of a cohesive structure made of a physicochemically stable and integral composite gel which includes an oil such as coconut oil, an aqueous phase and a linear, non-crosslinked copolyamino acid of Leu/Glu type (random or diblock). The microparticles have a controllable and adjustable size of between 0.05 and 500 &mgr;m.

Abstract: The present invention relates to microcapsules for the oral administration of medicinal and/or nutritional active principles (AP), which are smaller than or equal to 1000 .mu.m in size. These microcapsules consist of particles which are coated with a coating material consisting of a mixture of a film-forming polymer derivative, a hydrophobic plasticizer, a functional agent and a nitrogen-containing polymer. These microcapsules are also characterized by their ability to remain in the small intestine for a long time (at least 5 hours) and to allow, during the residence, release and absorption of the AP. The invention also relates to a process for the production of the said microcapsules.

Abstract: The invention relates to a crosslinkable polymer for use in optics and non-linear optics, which comprises at least one chromophore, characterized in that it has, on at least two of its ends, at least one reactive end group of a different chemical type from the group predominantly used in polymerization and the preparation of a polymer skeleton. Said reactive end group comprises at least one CC, CN, CS, SS or NS double bond and/or triple bond, and/or an epoxy group and/or a thiol group or a derivative of said groups, and the polymerization groups are selected from at least one of the following groups: urethane, ester, amide, imide, ether, carbon-carbon, sulfide, silane and siloxane, urethane and ester groups being particularly preferred. Application in optical and opto-electronic materials and devices.

Abstract: The present invention relates to an aerosol composition for forming a preferably hydrated membrane which after vaporizing comprises as least one hydrophobic phase containing at least one film-forming polymer at least partly solubilized in an organic solvent system. The polymer is selected from hydrophobic polyaminoacids, preferably from the polyaminoacids obtained from at least one of the amino acids alanine, valine, leucine, isoleucine, proline, methionine, phenylalanine, tryptophan, aspartic and glutamic acid esters, or the derivatives thereof. The compositions also comprises as least one hydrophilic phase, and at least one propellant. The preferably hydrated membrane formed by vaporizing this composition, the application of the composition and of the preferably hydrated membrane as a dressing, are also disclosed.

Abstract: The present invention relates to delivery vehicles which are useful for the administration of active principles (APs), preferably medicinal or nutritional active principles, in particular via the oral or parenteral route.The technical problem solved by the invention is that which consists in providing delivery vehicles composed of (nano)- or (micro)particles based on polyamino acids, and which are invert with respect to the AP (proteins), of controllable particle size, strong and inexpensive.According to the invention, the particles have an average size of less than 200 .mu.m and consist of a polyamino acid of the Leu/Glu type, in which Leu/Glu+Leu.gtoreq.3% and the M.sub.w .gtoreq.4,000 D.

Abstract: A method for preparing ceramic materials and/or precursors thereof from polysilanes of formula (I): ##STR1## in which: n.gtoreq.1, x+y=1, with:0.3.ltoreq..times..ltoreq.1 and,preferably, 0.5.ltoreq.x.ltoreq.0.8, 0.ltoreq.y.ltoreq.0.7.Pyrolytic efficiency and the quality of the final ceramics may be increased by pyrolysis carefully selected polysilanes (I) in the presence of a catalytic amount of at least one boron compound and optionally in the presence of at least one unsaturated cross-linking agent, preferably a vinyl cross-linking agent. This method is useful for preparing ceramic articles such as fibres, films, binders and matrices for use, inter alia, in electronics, electro-optics, semiconductor technology and aeronautics.

Abstract: The present invention relates to controlled-release microcapsules of acetylsalicylic acid which comprise particles of acetylsalicylic acid with a size of between 100 and 1000 .mu.m, coated with a coating material consisting of a mixture of a cellulosic film-forming polymeric derivative, an antiadherent, a plasticizer, a lubricant and a vinylic film-forming polymeric derivative. The invention further relates to a process for the preparation of said microcapsules.

Abstract: The present invention relates to a new polyesterimide of the type containing ester repeat functional groups E=--CO--O--, imide repeat functional groups I: ##STR1## and at least one chromophore, characterized in that it contains a quantity of recurrent amide functional groups capable of ring closure to imides which is smaller than or equal to 5 mol % relative to the sum of the imide functional groups and of the amide functional groups capable of ring closure to imides, which are present, and in that the polymerization functional groups consist essentially of E functional groups.This polyesterimide is preferably free from amide functional groups capable of ring closure to imides.One of the processes for obtaining this polyesterimide constitutes another subject-matter of the invention.Such a polymer is advantageously capable of behaving like a material that is transparent and/or active in nonlinear optics.

Abstract: The present invention relates to a method for the preparation of polyamino acids, with controlled molecular weights, by polymerization of N-carboxyanhydrides (NCAs) of at least one amino acid, using at least one initiator of the strong base type and in liquid medium, characterized in that it consists in including, in the liquid reaction medium, given amounts of water and/or of alcohol. Application: synthesis of polyamino acids with mechanical and rheological characteristics adapted to applications as biomaterials.

Abstract: The present invention relates to a modified collagen which is soluble in water and/or in aprotic polar organic solvents and which comprises free or substituted thiol functional groups carried by residues of cysteine or its derivatives, the residues being, at least partially, residues which are directly grafted onto the collagen chain, characterized in that it possesses a level of free or substituted thiol functional groups greater than 0.3, preferably 0.5 mM/g of collagen. The invention also relates to the production of these new collagen derivatives and to their application in the preparation of biomaterials, it being possible for the latter to be used especially in the manufacture of implants, prostheses or the like.

Abstract: The present invention relates to novel organic products resulting, for example, from the condensation of a dicarboxylic acid with a sulfur-containing amino acid or one of its derivatives. These products contain reactive thiol SH functions which can be oxidized to form disulfide bridges, resulting in polymers, which may or may not be crosslinked.These novel organic products correspond to the following formula: ##STR1## The invention also relates to the polymers and/or networks deriving from the products of formula (I) and to one of the methods for obtaining these products and their derivatives.Applications as biomaterials: sutures, ligatures, prostheses, adhesives or systems for the controlled release of active principles.

Abstract: The present invention relates to controlled-release microcapsules of acetylsalicylic acid which comprise particles of acetylsalicylic acid with a size of between 100 and 1000 .mu.m, coated with a coating material consisting of a mixture of a cellulosic film-forming polymeric derivative, an antiadherent, a plasticizer, a lubricant and a vinylic film-forming polymeric derivative. The invention further relates to a process for the preparation of said microcapsules.