Figure 1

PNA-FISH detection. A)-C) In smears: A) Susceptible strain in the red channel; B) Resistant strain in the same microscopic field in the green channel; C) Superimposition of both channels. D)-K) In gastric biopsy histological slides. D) Strain visualization using the Hp1 (A2143G) PNA probe; F) Hp2 (A2142G) PNA probe; H) Hp3 (A2142C) PNA probe; K) Hpwt (wild type strain) PNA probe; E),G),I) Visualization of the same microscopic field of D),F),H) with the red channel (negative controls for Hp1, Hp2 and Hp3); J) Visualization of the same microscopic field of K) with the green channel (negative control for Hpwt). Arrows indicate the presence of H. pylori infecting the gastric mucosa. (Original magnification × 600).