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@#【Abstract】 【Objective】To assess effect of calcofluor white and fluorescent dye labeled concanavalin A in Candida albicans growth and adhesion of cells.【Methods】Yeast cells of 20 strains of Candida albicans were labeled by calcofluor white and Alexa fluor 488 conjugated concanavalin A respectively. The growth of labeled Candida albicans were tested by counts of colony forming unit. Then yeast cells of Candida albicans were co-cultured with macrophages and enterocytes for half an hour. The adhesion of labeled Candida albicans to macrophages and enterocytes were observed by fluorescence microscopy.【Results】No difference was observed on the number of colony forming units between calcofluor white-labeled groupand control group(P=0.942). Also,no difference was observed on the number of colony forming units between Alexa fluor 488 conjugated concanavalin A-labeled group and control group. However,either the number of calcofluor white-labeled Candida albicans or Alexa fluor 488 conjugated concanavalin A-labeled Candida albicans that bound to macrophages was less than that in control group(P=0.000,respectively). Either the number of calcofluor white-labeled Candida albicans or Alexa fluor 488 conjugated concanavalin A-labeled Candida albicans that bound to enterocytes was less than that in control group(P = 0.000,respectively). Hyphae were observed in control group but not in calcofluor white group after yeast cells of Candida albicans were co-cultured with cells for half an hour.【Conclusions】Growth of Candida albicans was not changed,while its adhesion to cells was reduced after its labeling by calcofluor white and Alexa fluor 488 conjugated concanavalin A.The germination of Candida albicans was affected when it had been labeled by calcofluor white.
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<p><b>BACKGROUND</b>The prevalence of dermatophytoses and the development of new antifungal agents has focused interest on susceptibility tests of dermatophytes. The method used universally for susceptibility tests of dermatophytes was published as document (M38-A) in 2002 by the Clinical and Laboratory Standards Institute (CLSI), dealing with the standardization of susceptibility tests in filamentous fungi, though not including dermatophytes especially. However, it is not a very practical method for the clinical laboratory in routine susceptibility testing. In this test, we developed a novel rapid susceptibility assay-glucose consumption method (GCM) for dermatophytes.</p><p><b>METHODS</b>In this study, we investigated the antifungal susceptibilities of dermatophytes to itraconazole (ITC), voriconazole (VOC), econazole nitrate (ECN) and terbinafine (TBF) by glucose consumption method (GCM), in comparison to the Clinical and Laboratory Standards Institute (CLSI) M38-A method. Twenty-eight dermatophyte isolates, including Trichophyton rubrum (T. rubrum) (n = 14) and Trichophyton mentagrophytes (T. mentagrophytes) (n = 14), were tested. In the GCM, the minimum inhibitory concentrations (MICs) were determined spectrophotometrically at 490 nm after addition of enzyme substrate color mix. For the CLSI method, the MICs were determined visually.</p><p><b>RESULTS</b>Comparison revealed best agreement for TBF against T. mentagrophytes and T. rubrum, since MIC range, MIC50, and MIC90 were identical from two methods. However, for ITC and VOC, GCM showed wider MIC ranges and higher MICs than CLSI methods in most isolates. For ECN against T. rubrum, high MICs were tested by GCM (0.125-16 microg/ml) but not M38-A method (0.5-1 microg/ml). The overall agreements for all isolates between the two methods within one dilution and two dilutions for ITC, VOC, ECN and TBF was 53.6% and 75.0%, 57.1% and 75.0%, 82.1% and 89.3%, and 85.7 and 85.7%, respectively.</p><p><b>CONCLUSION</b>Measurement of glucose uptake can predict the susceptibility of T. rubrum and T. mentagrophytes to ECN and TBF.</p>