C. Polymicrobial biofilm formed in coculture by AF53470 sporelings and PA56402 grown on plastic cover slips for 48 h at 35°C. The biofilms were photographed using a Nikon Microscope Camera System equipped with SPOT image processing computer software [46]. With the SPOT program, each Objective (10× to 100×) of the microscope was calibrated using a stage micrometer as previously
described in the SPOT Software User Guide (Chapter 4, pages 76 and 77). The photomicrographs shown in Figure 1 were captured using the 60× Objective providing a total magnification of 600×. D. Quantification of 24-h and 48-h monomicrobial and polymicrobial biofilms of AF53470 and PA56402. The biofilm quantification Stem Cells inhibitor experiment by crystal violet binding assay was performed two times with eight replications for each group. The data were analyzed by two-way ANOVA and paired Student’s t-test using GraphPad Prism 5.0. The vertical bar PD173074 clinical trial on each histogram represents the standard error of the mean for
two independent experiments. The laboratory isolates AF36607 and PA27853 also produced similar monomicrobial and polymicrobial biofilms on plastic cover slips and Costar 6-well cell culture plates. Determination of the effects of antibiotics on biofilms Monomicrobial and polymicrobial biofilms of A. fumigatus and P. aeruginosa were developed in Costar 24-well cell culture plates as previously described. The biofilms were washed with distilled water (3 times, 1 ml each) and incubated with the appropriate concentrations of antimicrobial drug(s) for 24 h at 35°C. The drug-treated biofilms were washed and the adherent cultures containing either fungal or bacterial or a mixed population of fungal and bacterial cells were harvested by scraping the bottom of the wells of the cell culture plates using sterile wet swabs into 1 ml aliquots of sterile distilled water. The
cell suspension was vortexed vigorously most with sterile glass beads to disperse the cells, serially diluted 10 to 108 fold and 0.01 ml aliquots of the cell suspensions were plated on ciprofloxacin (50 μg/ml) or voriconazole (16 μg/ml) containing SD agar plates and incubated for 24 h at 35°C for selective growth. The number of CFUs for each group was determined and plotted against the drug concentration to assess the effectiveness of antibiotic treatment against biofilm bound cells. One of the disadvantages of using CFU assay to determine the MAPK inhibitor growth of filamentous fungi is the poor correlation between biomass and CFU values. We therefore performed a pilot experiment where 1 × 106 conidia were germinated in 24-well cell culture plates in 1 ml SD broth at 35°C form 0 h to 24 and the fungal growth was determined by CFU assay. The number of CFUs obtained was more or less correlated with the number of conidia, germinated conidia and sporelings grown for up to 12 h.