The absorbance was measured as before at 520 nm following vortex mixing for 5 s. The hydrophobicity was expressed as described
previously, as the percentage reduction in optical density of the test suspension compared with the control.[24, 25] Thus, the greater the change in absorbance, the greater the shift in Candida from the bulk medium to the interface (i.e. the more hydrophobic the Candida strain). Suspensions find more without xylene were used as the negative controls. C. albicans ATCC 90028 was used as a reference strain for all experiments and all these experiments were repeated on three separate occasions with duplicate determinations on each occasion. The effect of nystatin on each isolate was statistically analysed as done in similar previous studies.[18-20, 22-25] The data obtained from all three adhesion to BEC, germ tube and CSH assays were analysed using anova Dunnett’s t-tests, which treat one group as a control (unexposed
to nystatin), and compare the other group (exposed to nystatin) against it. Regression analysis by Pearson selleck products correlation coefficient (r) was used to determine the relationship between nystatin-induced suppressive effect on adhesion to BEC, germ tube formation and relative CSH of C. dubliniensis isolates. A P < 0.05 was considered statistically significant. The MIC (μg/ml) values of 20 isolates of C. dubliniensis to nystatin ranged from 0.09 to 0.78. Based on the equation PAFE = T-C, the mean in vitro PAFE (hours) on 20 oral isolates of C. dubliniensis following 1 h exposure and subsequent removal of nystatin was 2.17 h (Table 1). For instance, for the isolate CD1 the mean T was 4.25 h and mean C was 2.125 h. Hence, the PAFE (T-C) was 2.13 h. For all other isolates tested, the mean T and C values were approximately 4 and 2 h, respectively, giving an overall mean PAFE value of 2.17 h
for the tested isolates (Table 1). Mean SEM 2.17 0.045 74.45 0.71 95.92 0.29 34.81 1.38 The mean adhesion to BEC (yeast/50 BEC) of the 20 C. dubliniensis isolates unexposed to nystatin and following brief exposure to the drug was 208.51 and 53.21, respectively, giving a 74.45% mean Endonuclease percentage reduction (P < 0.0001; Tables 1 and 2). The percentage GT-positive cells of the 20 C. dubliniensis isolates unexposed to nystatin and following limited exposure to this antifungal was 25.31 and 1.01 respectively. Hence, compared with the control, exposure to nystatin almost completely inhibited GT formation with a mean percentage reduction of 95.92% (P < 0.0001; Tables 1 and 2). The mean CSH of the 20 C. dubliniensis isolates, unexposed controls and following limited exposure to nystatin, drug removal and subsequent determination of CSH by the biphasic aqueous-hydrocarbon assay was 14.89 and 9.84, respectively, with a mean percentage reduction of 34.81% (P < 0.05; Tables 1 and 2).