a barrier. During this process gas bubbles are separated from the medium at the top of the gas expander module. In consequence, medium leaving the container is oxygen-saturated but free of gas bubbles [8,9]. Broad spectrum of applications In the last years numerous papers were published dealing with the Minusheet perfusion culture system. The wide spectrum illustrates that the modular system was applied to generate specialized tissues in excellent cell biological quality used in tissue engineering, biomaterial research and advanced pharmaceutical drug toxicity testing. A complete list of these applications is found in the data bank ‘Proceedings in perfusion culture’ (see 'External links'). As demonstrated by numerous patents (DE 39 23 279, DE 42 00 446, DE 42 08 805, DE 44 43 902, DE 19530 556, DE 196 48 876 C2, DE 199 52 847 B4, US 5 190 878, US 5 316 945, US 5 665 599, J 2847669, DE 10 2005 002 938, PA 10 2004 054 125.6, PA 10 2005 001 747.9, patents pending) Will W. Minuth has invented the presented Minusheet perfusion culture system. Numerous pilot experiments with the Minusheet perfusion culture system were performed in the last years by Lucia Denk and Will W. Minuth. The experimental work is presently focusing on the creation of an artificial polyester interstitium to repair injured renal parenchyma. In 1992 the Minusheet perfusion culture system received the Philip Morris research award ‘Challenge of the Future’ in Munich, Germany. The award was handed over by Henry Kissinger, Hans Joachim Friedrichs and Paul Müller. To introduce the Minusheet perfusion culture system on the market, Katharina Lorenz-Minuth founded non-profit orientated Minucells and Minutissue Vertriebs GmbH (D-93077 Bad Abbach/Germany). External links Proceedings in Perfusion Culture Philip Morris Stiftung Minusheets Website References 1. Elaut G, Henkens T, Papeleu P, Snykers S, Vinken M, Vanhaecke T, Rogiers V (2006) Molecular mechanisms underlying the dedifferentiation process of isolated hepatocytes and their cultures. Curr Drug Metab 7(6):629-60. 2. Schuh E, Hofmann S, Stok K, Notbohm H, Müller R, Rotter N (2011) Chondrocyte redifferentiation in 3D: the effect of adhesion site density and substrate elasticity. J Biomed Mater Res A: DOI 10.1002/jbm.a.33226. 3. Zhang Y, Li TS, Lee ST, Wawrowsky KA, Cheng K, Galang G, Malliaras K, Abraham MR, Wang C, Marban E (2010) Dedifferentiation and proliferation of mammalian cadiomyocytes 2010 PLoS ONE 5(9):e12559. 4. Liu Y, Jiang X, Yu MK, Dong J, Zhang X, Tsang LL,