title: Helicobacter pylori virulence factors and their role in peptic ulcer diseases in Turkey.
abstract: OBJECTIVE
  The role of virulence factors present in Helicobacter pylori (H. pylori) strains and the characterization of such factors being predictive of specific disease is still not clear. In this study, the cagA, vacA alleles and the recently characterized vacA i-region and dupA and their association with the severity of the disease was determined.
  
  
  METHODS
  Antral biopsies from 91patients with peptic ulcer (PU) (n = 41), gastritis (n = 48) and gastric cancer (GC) (n = 2) were analyzed for the presence of H. pylori by the CLO-test and PCR. A 79/91 (86%) patients were positive for H. pylori by either PCR or by both PCR and CLO-test. PCR-based typing of H. pylori isolates was performed on DNA extracted directly from biopsy samples.
  
  
  RESULTS
  The cagA+ strains were found more likely to be associated with vacA s1 than s2. The vacA i1 allele detected in 16/23 (70%) of samples had significant association with duodenal ulcers than those 16/37 (44%) of gastritis (P < 0.04). No significant association was found between dupA and duodenal ulcer. This study provided more evidence that the vacA i1 allele is one of the virulence factors of H. pylori that had significant association with severe outcome.
authors.affiliation: Fatih University, Faculty of Science, Department of Biology, Istanbul, Turkey.
authors.forename: I E
authors.initials: IE
authors.lastname: Tuncel
authors.forename: N R
authors.initials: NR
authors.lastname: Hussein
authors.forename: B K
authors.initials: BK
authors.lastname: Bolek
authors.forename: S
authors.initials: S
authors.lastname: Arikan
authors.forename: B A
authors.initials: BA
authors.lastname: Salih
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000032:analysis; D001426:Bacterial Proteins / Q000032:analysis / Q000502:physiology; D005260:Female; D016481:Helicobacter Infections / Q000235:genetics; D016480:Helicobacter pylori / Q000472:pathogenicity*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology*; D011706:Pyloric Antrum / Q000382:microbiology; D014421:Turkey; D014774:Virulence; D037521:Virulence Factors / Q000032:analysis / Q000502:physiology; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C528428:DupA protein, Helicobacter pylori; C074689:VacA protein, Helicobacter pylori; D037521:Virulence Factors; C080866:cagA protein, Helicobacter pylori