Cells, animal conditions

This review is focused on the evaluation of the interaction between the artificial material and cells in cell culture conditions. In comparison with in vivo experiments, where both material and contacting cells are subjeeted to multiple and complex influences of the whole organism, the cell eulture represents a relatively simple and well-defined system. This system enable sereening of a wide range of materials and their surfaee modification in order to select the most appropriate variants for testing on laboratory animals and then for clinical studies. Therefore, the use of cell eulture eonsiderably saves these animals, and thus fulfills the ethical requirements for advanced scientific research. 

Trehalose is a relatively new bulk sweetener with potential for use in soft drinks. It is a di-glucose sugar and it occurs in nature in shellfish and mushrooms, where it confers a degree of protection to plant and animal cells in conditions causing dehydration. This led to its use as a cryoprotectant in freeze-drying systems in the pharmaceutical industry. In food markets, its potential use is as a bulk sweetener. It is manufactured using the Hayashibara patented process using starch as a raw material. The process involves enzymatic conversion and crystallisation to the trehalose dehydrate crystal (LFRA, 2001). 

Alrubeai, M., R.P. Singh, M.H. Goldman, and A.N. Emery. 1995. Death mechanisms of animal cells in conditions of intensive agitation. Biotechnol Bioeng 45 463-472. 

Langheinrich C, Nienow AW, Eddleston T, Stevenson NC, Emery AN, Clayton TM, Slater NKH. (2002) Oxygen transfer in stirred bioreactors under animal cell culture conditions. Food Bioproduct. Proc. (Trans I Chem.E, Part C), 80 39-44. 

PVDF-based microporous filters are in use at wineries, dairies, and electrocoating plants, as well as in water purification, biochemistry, and medical devices. Recently developed nanoselective filtration using PVDF membranes is 10 times more effective than conventional ultrafiltration (UF) for removing vimses from protein products of human or animal cell fermentations (218). PVDF protein-sequencing membranes are suitable for electroblotting procedures in protein research, or for analyzing the phosphoamino content in proteins under acidic and basic conditions or in solvents (219). 

Biosynthesis of Protein. The dynamic equilibrium of body protein was confirmed by animal experiments using A/-labeled amino acids in 1939 (104). The human body is maintained by a continuous equilibrium between the biosynthesis of proteins and their degradative metabolism where the nitrogen lost as urea (about 85% of total excreted nitrogen) and other nitrogen compounds is about 12 g/d under ordinary conditions. The details of protein biosynthesis in living cells have been described (2,6) (see also Proteins). 

---