TABLE 5.
Enhancement of gentamicin activity at 24 h on residual adherent S. aureus A970862 after 4 h of PMMA incubation with bacteria and 4% P407
| Treatments (adherence assay, treatment) | Surface bacterial density (log10 CFU/cm2)
|
% Residual adherent bacteria (P value)
|
Bacterial density evolutionc | ||
|---|---|---|---|---|---|
| Preantibiotic | Finala | Vs control, control | Vs control, gentamicinb | ||
| Control, control | 6.89 ± 0.10 | ||||
| Control, gentamicin (1 × MIC) | 4.77 | 6.78 ± 0.40 | 76.54 (NS)d | 102 | |
| Control, gentamicin (2 × MIC) | 4.77 | 5.62 ± 0.15 | 5.36 (<0.001) | 7.14 | |
| P407, control | 5.74 ± 0.90 | 7.12 (<0.02) | |||
| P407, gentamicin (1 × MIC) | 3.89 | 4.71 ± 0.22 | 0.66 (<0.001) | 0.86 (<0.01) | 6.54 |
| P407, gentamicin (2 × MIC) | 3.89 | <1 | <10−4 (<0.001) | <10−3 (<0.001) | 0.001 |
a
The data are means ± standard deviations of six isolates.
b
The data were compared at the same concentration of gentamicin.
c
Surface bacterial density change during exposure to gentamicin is the final surface bacterial density divided by the preantibiotic surface bacterial density.
d
NS, no significant difference.