Abstract: A gelling cell culture medium useful for forming a three dimensional matrix for cell culture in vitro is prepared by copolymerizing an acrylamide derivative with a hydrophilic comonomer to form a reversible (preferably thermally reversible) gelling linear random copolymer in the form of a plurality of linear chains having a plurality of molecular weights greater than or equal to a minimum gelling molecular weight cutoff, mixing the copolymer with an aqueous solvent to form a reversible gelling solution and adding a cell culture medium to the gelling solution to form the gelling cell culture medium. Cells such as chondrocytes or hepatocytes are added to the culture medium to form a seeded culture medium, and temperature of the medium is raised to gel the seeded culture medium and form a three dimensional matrix containing the cells. After propagating the cells in the matrix, the cells may be recovered by lowering the temperature to dissolve the matrix and centrifuging.

Abstract: The invention provides an adjustable ligament anchor for attaching a ligament to a bone. The ligament anchor comprises a housing having an exterior surface, an interior surface, an intra-articular end and an opposite extra-articular end. The interior surface defines a bore that extends longitudinally through the housing, joining the ends. A member is dimensioned to be received within the bore and having a first end and an opposite second end, wherein the ligament is attached to the first end. Adjusting means comprise a longitudinal chamber opening through the second end, and extending into at least a portion of the member. The chamber has threads and is dimensioned to receive a screw having a shaft with threads complimentary to threads in chamber.