• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.239-243
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• 2010

Candidiasis is one of the most common causes of late-onset infection among very-low-birth-weight infants (VLBW) in most neonatal intensive care units and is associated with significant morbidity and mortality. Standard therapy consists of the administration of amphotericin B, amphotericin B complex, and fluconazole. In many cases, candidiasis is not easily eradicated, despite the administration of these drugs. We report our experience of the addition of high-dose caspofungin to the conventional antifungal drugs in a VLBW infant with refractory candidemia.

• Biomedical Science Letters
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• v.22 no.4
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• pp.174-183
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• 2016

In the present study, a serum-based minimum inhibitory concentration (MIC) testing to caspofungin was optimized and evaluated to solve the limitations of the conventional Clinical and Laboratory Standards Institute (CLSI) guideline-based antifungal agent MIC test and the usefulness of this testing for clinical application was determined. A total of 105 Candida albicans clinical isolates were used for measuring MIC to caspofungin. Results showed that growth characteristics were different according to types of serum and the mouse serum was the most suitable for this assay. In order to measure the optimal concentration of mouse serum, 0 to 100% mouse serum were added to the media during fungal culture. The optimal concentration of serum was 50% when consideration of antifungal agent administration and inoculum size, serum components and ease of hyphae separated, and the consideration of the degree of growth. In comparison of the usefulness between the conventional Alamar-modified broth microdilution MIC assay and 50% mouse serum-based MIC testing, the range of $MIC_{80}$ of the Alamar-modified broth microdilution MIC assay was $0.13{\sim}2.0{\mu}g/mL$ (SD ${\pm}0.42{\mu}g/mL$) and that of the 50% mouse serum-based MIC assay was $2.0{\sim}32.0{\mu}g/mL$ (SD ${\pm}9.01{\mu}g/mL$). The range of $MIC_{50}$ of the Alamar-modified broth microdilution MIC assay was $0.13{\sim}2.0{\mu}g/mL$ (SD ${\pm}0.40{\mu}g/mL$) and that of the 50% mouse serum-based MIC assay was $1.0{\sim}16.0{\mu}g/mL$ (SD ${\pm}2.36{\mu}g/mL$). The MICs of 50% mouse serum-based MIC testing was increased by up to 4 to 64 times than Alamar-modified broth microdilution MIC assay. In conclusion, a 50% mouse serum-based MIC assay was more useful for measuring MIC in Candida albicans clinical isolates than conventional colorimetric broth microdilution MIC testing.

• Mycobiology
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• v.31 no.2
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• pp.95-98
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• 2003

Aantifungal agents were tested against 30 clinical isolates of Cryptococcus neoformans var. neoformans using the NCCLS method(M27-A2). Posaconazole, itraconazole and amphotericin B had lower MIC than the remaining four antifungal agents. The MIC result for posaconazole was over 220-fold lower active than fluconazole. Fluconazole MICs for most isolates fell within the dose-dependant range. The overall MIC ranges and $MIC_{50}s$ were amphotericin B(0.03-0.25; 0.25), fluconazole(0.5-64; 16), itraconazole(0.015-1; 0.125), terbinafine(0.06->2; 1), caspofungin(8-32; 32), voriconazole(0.015-0.5; 0.25), and posaconazole(0.015-0.25; 0.06 ${\mu}g/ml$), respectively. In conclusion, the $MIC_{50}s$ of these drugs did not exhibit any sign of an upward shift with the exception of fluconazole and tendency cross-resistance between the seven drugs was not observed. We conclude that in vitro resistance to antifungal agents has not significantly changed despite the recent wide-spread use of triazoles for long-term treatment of Cryptococcal meningitis.

• Biomedical Science Letters
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• v.30 no.2
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• pp.73-80
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• 2024

The aim of this study was to investigate the distribution and antifungal susceptibilities of Candida spp. from blood culture to provide useful information on empirical treatment of Candidemia. We investigated distribution and antifungal susceptibilities of Candida spp. isolated from blood culture during an 8-years (2016-2023) in a C-University hospital. Over 8 years, 1,182 Candida strains from blood culture were isolated, which was fourth most common cause of bloodstream infection. Among nonduplicated 350 Candida strains, C. albicans was the most common with 45.43%, followed by C. glabrata (17.43%), C. tropicalis (17.43%), C. parapsilosis (14.86%), C. guilliermondii (1.71%), C. krusei (0.86%), C. lusitaniae (0.86%), C. ciferrii (0.57%). In the antifungal susceptibility testing on 323 Candida strains, the non-susceptibility rate was 2.48% for amphotericin B, 1,71% for flucytosine, 3.09% for fluconazole, 4.66% for voriconazole, 5.57% for caspofungin, and 0.62% for micafungin. In particular, C. albicans showed non-susceptibility of 8.23% to voriconazole, and C. glabrata showed 14.81% and 24.59% to fluconazole and caspofungin, respectively. These data showed that the prevalence of candidemia is very common, and antifungal resistance in Candida spp., especially C. glabrata, is increasing. Therefore, periodic surveillance of prevalence and antifungal susceptibility of blood culture is very important for clinical laboratory.

• Mycobiology
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• v.43 no.2
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• pp.150-156
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• 2015

2',4'-Dihydroxychalcone (2',4'-DHC) was identified from a heat shock protein 90 (Hsp90)-targeting library as a compound with Hsp90 inhibitory and antifungal effects. In the presence of 2',4'-DHC ($8{\mu}g/mL$), radial growth of Aspergillus fumigatus was inhibited 20% compared to the control, and green pigmentation was completely blocked. The expression of the conidiation-associated genes abaA, brlA, and wetA was significantly decreased (approximately 3- to 5-fold) by treatment with 2',4'-DHC. The expression of calcineurin signaling components, cnaA and crzA, was also significantly reduced. The inhibitory effects of 2',4'-DHC on metabolic activity and mycelial growth were significantly enhanced by combination treatment with itraconazole and caspofungin. Docking studies indicated that 2',4'-DHC bind to the ATPase domain of Hsp90. These results suggest that 2',4'-DHC act as an Hsp90-calcinurin pathway inhibitor.