title: Carcinogenesis in rats subjected to a new model ureterosigmoidostomy and treated with L-lysine.
abstract: To evaluate the effects of L-lysine on the intestinal and urothelial epithelium of rats subjected to ureterosigmoidostomy (new model for surgical carcinogenesis).
  Forty-two rats, 9 weeks of age, were divided into 6 groups. Animals in groups A, B, C were subjected to ureterosigmoidostomy (US) and treated with L-lysine, celecoxib and H2O, respectively. Groups D, E and F (non-operated controls) received L-lysine, celecoxib and H2O, respectively. The L-lysine dose was 150 mg/kg and that of celecoxib was 20 mg/kg. The colon was analyzed for the presence of aberrant crypt foci (ACF) under a stereomicroscope.The tissue was stained with hematoxylin and eosin and PAS alcian blue.
  There were rare ACF, and there was no statistically significant difference between the groups. Histopathologic study of the ureteral epithelium identified moderate to severe urothelial hyperplasia in rats with ureterosigmoidostomy. Transitional hyperplasia in the ureters of animals receiving L-lysine (A) showed an apparent difference compared to the control (C) (P=0.2424). There was no dysplasia or atypia.
  L-lysine does not promote carcinogenesis of the intestinal and urethelial epithelium of rats subjected to ureterosigmoidostomy at the doses and times studied.
authors.affiliation: Fellow Master degree, Postgraduate Program in Pathology, Department of Pathology, Universidade Federal do Ceará (UFC), Brazil. Intellectual and scientific content of the study, histopathological examinations, technical procedures, manuscript preparation.
authors.forename: Alessandra Marques Dos
authors.initials: AM
authors.lastname: Santos
authors.affiliation: Graduate student, Scientific Iniciation Program, UFC, Fortaleza-CE, Brazil. Technical procedures.
authors.forename: Joao Paulo Ferreira
authors.initials: JP
authors.lastname: Coelho
authors.affiliation: Graduate student, Scientific Iniciation Program, UFC, Fortaleza-CE, Brazil. Technical procedures.
authors.forename: Camila de Carvalho
authors.initials: CC
authors.lastname: Juanes
authors.affiliation: Graduate student, Scientific Iniciation Program, UFC, Fortaleza-CE, Brazil. Technical procedures.
authors.forename: Rafael Barbosa de
authors.initials: RB
authors.lastname: Azevedo
authors.affiliation: Graduate student, Scientific Iniciation Program, UFC, Fortaleza-CE, Brazil. Acquisition of data.
authors.forename: Nayanna de Oliveira Ramos
authors.initials: NO
authors.lastname: Melo
authors.affiliation: PhD, Researcher, Núcleo de Pesquisa e Desenvolvimento de Medicamentos (NPDM), School of Medicine, UFC, Fortaleza-CE, Brazil. Analysis and interpretation of data, statistical analysis.
authors.forename: Francisco Vagnaldo Fechine
authors.initials: FV
authors.lastname: Jamacaru
authors.affiliation: PhD, Associate Professor, Department of Pathology, UFC, Fortaleza-CE, Brazil. Conception and design of the study, technical procedures, critical revision, supervised all phases of the study.
authors.forename: Conceição Aparecida
authors.initials: CA
authors.lastname: Dornelas
mesh_terms: D058739:Aberrant Crypt Foci / Q000473:pathology*; D000818:Animals; D063646:Carcinogenesis; D012809:Colon, Sigmoid / Q000601:surgery*; D004195:Disease Models, Animal; D005260:Female; D007413:Intestinal Mucosa / Q000473:pathology; D007414:Intestinal Neoplasms / Q000209:etiology*; D008239:Lysine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D054047:Surgical Stomas / Q000009:adverse effects; D014519:Ureterostomy / Q000009:adverse effects* / Q000379:methods; D001749:Urinary Bladder Neoplasms / Q000209:etiology; D014547:Urinary Diversion; D014571:Urologic Neoplasms / Q000209:etiology*
chemical_list: D008239:Lysine