Rabbits implantable matrices

Feldman LJ, Mazighi M, Scheuble A, et al. Differential expression of matrix metalloproteinases after stent implantation and balloon angioplasty in the hypercholesterolemic rabbit. Circulation 2001 103 3117-3122. 

Meikle, M.C. Papaioannou, S. Ratledge, T.J. Speight, P.M. Watt-Smith, S.R. Hill, P.A. Reynolds, J.J. Effect of poly D-lactide-co-glycolide implants and xenogeneic bone matrix-derived growth factors on calvarial bone repair in the rabbit. Biomaterials 1994, 15 (7), 513-521. 

The biocompatibility of poly(CPP), poly(TA), and copolymers of CPP SA and CPP TA implanted in the corneas of rabbits was studied. Six weeks after implantation, the cornea remained clear and showed no evidence of corneal edema or neovascularization, indicating biocompatibility of the polymer matrix implant. 

In vivo capsule viability screen. The intrinsic behavior of the cells, diffusion of nutrients and cofactors, and immunogenicity all affect the viability and function of the cells in capsules. Multiple capsule configurations and cell matrix membrane combinations were tested. The combination of cell ECM scaffold was encapsulated with different membranes and capsules were implanted into CNS and ocular sites (such as rat ventricle, rabbit eye, dog eye, pig eye, and sheep intrathecal space). The optimal cell-matrix membrane combinations that show longevity and functional stability in vivo were chosen for further development. 

Shen W, Chung K, Wang G. Demineralized bone matrix in the stabilization of porous-coated implants in bone defects in rabbits. Clin Orthop 1993 293 346-352. 

Wu and co-workers [13] incorporated copolymer poly(3HB-co-3HV) with calcium silicate(s) (CS) to increase the hydrophilicity of the copolymer in order to enhance cell adhesion on scaffolds used for cartilage tissue engineering. Interactions between poly(3HB-co-3HV)/CS composite scaffolds and chondrocytes in vitro and the formation of neocartilage were evaluated after the implantation of scaffolds into rabbits. It was found that the adhesion of chondrocytes onto the scaffolds and cell proliferation improved with the addition of CS. Enhanced penetration of chondrocytes into the scaffolds was observed with the increase in hydrophilicity of the poly(3HB-co-3HV)/CS composite scaffolds. A higher amount of collagen and glycosaminoglycan were detected in the composite scaffold compared with pure poly(3HB-co-3HV), indicating that poly(3HB-co-3HV)/CS composite scaffolds stimulated the extracellular matrix synthesis of chondrocytes. 

Mesenchymal stem cells harvested from rabbits were induced into osteoblasts in vitro and were cultured for a week, statically loaded onto the porous hydroxyapatite + chitin matrices and implanted into bone defects of the rabbit femur for 2 months. The histology of explants showed bone regeneration with the biodegradation of the hydroxyapatite + chitin matrix. Similarly, green fluorescence protein transfected mesenchymal stem cells-induced osteoblasts were also loaded onto porous hydroxyapatite + chitin matrices and implanted into the rabbit femur. Mesenchymal stem cells-induced osteoblasts did not only proliferate but also recruited surrounding tissue to grow in. The hydroxyapatite + chitin matrix qualified for tissue-engineered bone substitutes (Ge et al. 2004). 

The enzyme matrix of the Bessman-Schultz sensor is made of thin closely-woven rayon acetate cloth (coated on one side with water-proof pressure-sensitive adhesive) impregnated with a glucose oxidase mixture, dried in air, and cross-linked with glutar-aldehyde. The resultant covalently-bound enzyme is very resistant to degradation by body fluids, showing less than 10 percent decrease in its response to physiological concentrations of glucose after subcutaneous implantation in a rabbit for 11 days and only about 50 percent loss in activity after 6 months. vitro,... 

Gliadel - a controlled-delivery polymer wafer is the combination of a copolyanhydride matrix consisting of CPP and sebacic acid (20/80 mol. ratio) in which an anticancer agent is physically admixed. Clinical investigations of Gliadel implants in rabbit brains have shown limited toxicity, initial activity and fast excretion of decomposition products as free acids (J4). 

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