title: New biliary endoprosthesis less liable to block in biliary infections: description and in vitro studies.
abstract: OBJECTIVE
  To test in vitro stents made from a new biomaterial that is less liable to encourage adhesion of bacteria that may lead to blockage of the stent.
  
  
  METHODS
  Laboratory experiment.
  
  
  METHODS
  University hospital, Italy.
  
  
  METHODS
  15 polyethylene biliary endoprostheses that had been removed endoscopically a mean of 151 days (range 55416) after insertion. PUPA, a biomaterial that contains polyamidoamine cross-linked to polyurethane chains. This can bind large quantities of heparin and HyalSx (hyaluronic acid at a different stage of sulphation) in a stable fashion.
  
  
  METHODS
  Incidence of blockage and growth of pathogens in the polyethylene biliary prostheses. Adhesion of pathogens to PUPA in vitro on electron microscopy.
  
  
  RESULTS
  12 of 15 polyethylene prostheses were blocked by brown concretions composed of calcium bilirubinate, palmitate, and little cholesterol. All concretions grew more than one pathogen, and the growth always included Escherichia coli. Of the 5 PUPA stents tested, only 1 had bacteria sticking to their surfaces.
  
  
  CONCLUSIONS
  These results confirm previous studies that showed that HyalSx appreciably inhibited the adhesion of bacteria and is therefore a suitable material for the manufacture of biliary stents.
authors.affiliation: Interuniversity Center for Research in Hepatobiliary Disease, Institute of Surgical Clinics, Siena, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Cetta
authors.forename: R
authors.initials: R
authors.lastname: Rappuoli
authors.forename: G
authors.initials: G
authors.lastname: Montalto
authors.forename: C
authors.initials: C
authors.lastname: Baldi
authors.forename: M
authors.initials: M
authors.lastname: Gori
authors.forename: D
authors.initials: D
authors.lastname: Cetta
authors.forename: M
authors.initials: M
authors.lastname: Zuckermann
authors.forename: A
authors.initials: A
authors.lastname: Magnani
authors.forename: R
authors.initials: R
authors.lastname: Barbucci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001660:Biliary Tract Diseases / Q000517:prevention & control*; D001662:Biliary Tract Surgical Procedures / Q000295:instrumentation*; D001672:Biocompatible Materials / Q000737:chemistry; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D009757:Nylons / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D011474:Prosthesis Design; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000517:prevention & control*; D015607:Stents
chemical_list: D001672:Biocompatible Materials; D009757:Nylons; D011073:Polyamines; D011140:Polyurethanes