Abstract: The present invention relates to an injectable homogeneous aqueous solution of chitosan containing, in a physiologically acceptable medium, between 0.1 and 4.5% by weight of a chitosan having a degree of acetylation less than 20% and a weight average molecular mass of between 100,000 and 1,500,000 g/mol, said solution having a pH greater than or equal to 6.2, and advantageously between 6.2 and 7.2, said solution not containing any chitosan having a degree of acetylation greater than 20%, said solution being liquid and homogeneous at ambient temperature.

Abstract: A method for preparing an aqueous hyaluronic acid gel, including the following steps: a) preparing a crosslinked aqueous hyaluronic acid gel, b) homogenising the aqueous gel formed in step (a) by rolling, c) neutralising the aqueous gel homogenised in step (b). Also, an aqueous hyaluronic acid gel able to be obtained by such a method. Further, the cosmetic use of such an aqueous gel in tissue repair or reconstruction, in particular for filling lines and wrinkles, or the medical use of the aqueous gel in tissue repair or reconstruction.

Abstract: An aqueous composition of chitosan including between 0.1 and 5 wt.-% chitosan relative to the total weight of the composition, for use in increasing the volume and/or number of adipocytes. The increase in the volume and/or number of adipocytes allows for use in the treatment of or combating against ageing of the skin, for filling in skin defeats, or the repair or reconstruction of continuous or subcutaneous tissues.