FIG 8.
Activity of antibiotics against biofilms grown in ASM(+) for 4 CF clinical isolates in comparison with that for PAO1 and thereafter incubated with antibiotics (ciprofloxacin, ceftazidime, meropenem, tobramycin, and colistin) at their human Cmax (Table 1) or at 100 mg/liter (the maximal concentration tested in the concentration-response curves for PAO1 in Fig. 3) for 24 h. The graphs show the reduction in the log10 number of CFU (left) or in the log10 OD570 of crystal violet compared to the values for the untreated control. Data are means ± SEM from 2 independent experiments in 3 replicates for CFU and from 2 experiments in 2 replicates for biomass. Statistical analyses were performed by 1-way analysis of variance with Dunnett’s post hoc test comparing each isolate with PAO1. ***, P < 0.001; **, P < 0.01; *, P < 0.05.