Figure 6.

(A) PCNA-positive (PCNA⁺) cells at the end of day 5 in samples intermittently exposed to MF and/or incubated for 42 h. Data were normalized to sham-exposed controls and expressed as the means ± SEM of 8 and 3 experimental replicates, at 10 and 100 μT, respectively. ^**P<0.01, ^***P<0.001 (ANOVA followed by the Student’s t-test). (B) Representative example of immunostaining in controls and MF-exposed cells (10 μT). PCNA⁺ cells (lower panels) and Hoechst nuclear staining (upper panels). The PCNA⁺ rate was calculated as the number of cells expressing PCNA divided by the number of Hoechst-stained nuclei (total cell number).