title: Tubular Constructs as Artificial Urinary Conduits.
abstract: OBJECTIVE
  A readily available artificial urinary conduit might be substituted for autologous bowel in standard urinary diversions and minimize bowel associated complications. However, the use of large constructs remains challenging as host cellular ingrowth and/or vascularization is limited. We investigated large, reinforced, collagen based tubular constructs in a urinary diversion porcine model and compared subcutaneously pre-implanted constructs to cell seeded and basic constructs.
  
  
  METHODS
  Reinforced tubular constructs were prepared from type I collagen and biodegradable Vicryl® meshes through standard freezing, lyophilization and cross-linking techniques. Artificial urinary conduits were created in 17 female Landrace pigs, including 7 with a basic untreated construct, 5 with a construct seeded with autologous urothelial and smooth muscle cells, and 5 with a free graft formed by subcutaneous pre-implantation of a basic construct. All pigs were evaluated after 1 month.
  
  
  RESULTS
  The survival rate was 94%. At evaluation 1 basic and 1 cell seeded conduit were occluded. Urinary flow was maintained in all conduits created with pre-implanted constructs. Pre-implantation of the basic construct resulted in a vascularized tissue tube, which could be used as a free graft to create an artificial conduit. The outcome was favorable compared to that of the other conduits. Urinary drainage was better, hydroureteronephrosis was limited and tissue regeneration was improved.
  
  
  CONCLUSIONS
  Subcutaneous pre-implantation of a basic reinforced tubular construct resulted in a vascularized autologous tube, which may potentially replace bowel in standard urinary diversions. To our knowledge we introduce a straightforward 2-step procedure to create artificial urinary conduits in a large animal model.
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: marije.sloff@radboudumc.nl.
authors.forename: Marije
authors.initials: M
authors.lastname: Sloff
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Vasileios
authors.initials: V
authors.lastname: Simaioforidis
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Dorien M
authors.initials: DM
authors.lastname: Tiemessen
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Heinz P
authors.initials: HP
authors.lastname: Janke
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Barbara B M
authors.initials: BB
authors.lastname: Kortmann
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Luc A J
authors.initials: LA
authors.lastname: Roelofs
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Geutjes
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Egbert
authors.initials: E
authors.lastname: Oosterwijk
authors.affiliation: Department of Urology, Radboud Institute for Molecular Life Sciences and Amalia's Children Hospital, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Wout F J
authors.initials: WF
authors.lastname: Feitz
mesh_terms: D000818:Animals; D001705:Bioprosthesis; D024042:Collagen Type I / Q000737:chemistry*; D005260:Female; D008422:Materials Testing; D023421:Models, Animal; D011098:Polyglactin 910; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D001743:Urinary Bladder / Q000601:surgery; D014547:Urinary Diversion / Q000379:methods*
chemical_list: D024042:Collagen Type I; D011098:Polyglactin 910
keywords: collagen type 1; polyglactin 910; regenerative medicine; tissue engineering; urinary diversion