Sensitization of <it>Candida albicans</it> biofilms to various antifungal drugs by cyclosporine A

<p>Abstract</p> <p>Background</p> <p>Biofilms formed by <it>Candida albicans</it> are resistant towards most of the available antifungal drugs. Therefore, infections associated with <it>Candida</it> biofilms are considered as a threat to immunocompromised patients. Combinatorial drug therapy may be a good strategy to combat <it>C. albicans</it> biofilms.</p> <p>Methods</p> <p>Combinations of five antifungal drugs- fluconazole (FLC), voriconazole (VOR), caspofungin (CSP), amphotericin B (AmB) and nystatin (NYT) with cyclosporine A (CSA) were tested <it>in vitro</it> against planktonic and biofilm growth of <it>C. albicans</it>. Standard broth micro dilution method was used to study planktonic growth, while biofilms were studied in an <it>in vitro</it> biofilm model. A chequerboard format was used to determine fractional inhibitory concentration indices (FICI) of combination effects. Biofilm growth was analyzed using XTT-metabolic assay.</p> <p>Results</p> <p>MICs of various antifungal drugs for planktonic growth of <it>C. albicans</it> were lowered in combination with CSA by 2 to 16 fold. Activity against biofilm development with FIC indices of 0.26, 0.28, 0.31 and 0.25 indicated synergistic interactions between FLC-CSA, VOR-CSA, CSP-CSA and AmB-CSA, respectively. Increase in efficacy of the drugs FLC, VOR and CSP against mature biofilms after addition of 62.5 μg/ml of CSA was evident with FIC indices 0.06, 0.14 and 0.37, respectively.</p> <p>Conclusions</p> <p>The combinations with CSA re<it>s</it>ulted in increased susceptibility of biofilms to antifungal drugs. Combination of antifungal drugs with CSA would be an effective prophylactic and therapeutic strategy against biofilm associated <it>C. albicans</it> infections.</p

Extraction and detection of Mycobacterium leprae DNA from ZNCF-stained skin smear slides for better identification of negative skin smears

Abstract Identification of Mycobacterium leprae , which causes leprosy, is done by Ziehl Neelsen Carbol Fuchsin (ZNCF) stained slit skin smear microscopy that aids in the diagnosis and quantification of approximate bacterial load carried by the patient. We attempted M. leprae DNA extraction from 46 stained slit skin smear negative slides, using Proteinase K and SDS lysis, followed by ethanol precipitation. M. leprae specific primers (16SrRNA) were used for PCR-based amplification of DNA. We could detect M. leprae DNA in 15 (32.6%) samples. The method can be useful in the diagnosis of apparently slit skin smear negative leprosy cases