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1 You can view your results on THURSDAY 28.06.2018, from 9.30 AM to 10.30 A.M., at Prof. Raimondi’s office, building n. 6 “Giulio Natta”, North tower, second floor. Surname_________ Name_____________registration ID (matricola)_____________ Technologies for regenerative medicine - Prof. Manuela T. Raimondi 2018.06.19 - examination theme Read the text below and answer, point by point, to the related questions. The Bioartificial kidney To create a bioengineered organ, a rat kidney is decellularised by detergent perfusion, yielding an acellular scaffold with vascular, cortical and medullary architecture, a collecting system and ureters. To regenerate functional tissue, MSCs are seeded and differentiated on this scaffold. This recellularised construct is perfused with complete culture medium (CM) in a whole-organ bioreactor. The resulting graft produces rudimentary urine in vitro when perfused through its intrinsic vascular bed. The generic micro-vascularized unit of the construct may be modelled as a tissue cylinder with radius R and length L, containing a co-axial capillary of radius d. These units are aligned in direct contact between each other. Consider an individual micro-vascularized unit during perfused bioreactor culture. The oxygen diffusion coefficient in the recellularised extracellular matrix is constant and equal to D. Assume the Péclet number of this system greater than 1 and the average flow rate of the culture medium very high. The oxygen concentration in the culture medium is constant and equal to Co. After culture in the bioreactor, the recellularised bioartificial kidney is transplanted in an orthotopic position in a rat model of chronic nephropathy, for which the conventional therapy is hemodialysis. The grafts were perfused by the recipient's…