scholarly journals Effectiveness of quinolone antibiotics in modulating the effects of antifungal drugs.

1997 ◽  
Vol 41 (11) ◽  
pp. 2518-2521 ◽  
Author(s):  
A M Sugar ◽  
X P Liu ◽  
R J Chen
Keyword(s):  
Amphotericin B ◽  
Murine Model ◽  
Antifungal Drugs ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Antibacterial Drugs ◽  
Quinolone Antibacterial Drugs ◽  
Gyrase A ◽  
Yeasts And Molds

Quinolone antibacterial drugs inhibit DNA gyrase, a type 2 topoisomerase. Since topoisomerases are present in eukaryotic cells, it was of interest to evaluate the antifungal activities of two clinically available quinolones, ciprofloxacin and trovafloxacin, alone and in combination with amphotericin B or fluconazole, in vitro against Candida albicans and in a murine model of invasive candidiasis. The in vitro activity of trovafloxacin was also tested against other yeasts and molds. In vitro, trovafloxacin exhibited no antifungal activity against any of the fungi (MIC, >250 microg/ml). There was also no effect of the quinolone on the in vitro activity of either antifungal drug. Marked antifungal effects were seen, however, in the murine model of candidiasis. In all experiments, control mice infected intravenously with C. albicans were dead by day 24. While either quinolone had minimal effects on survival of mice when used alone in oral doses of up to 40 mg/kg twice daily, the combination of the quinolone with fluconazole (40 or 80 mg/kg given twice daily by oral gavage) was more effective in prolonging survival than was fluconazole alone. Colony counts of kidneys on days 12 and 30 showed similar reductions in C. albicans recovered from mice treated with fluconazole with or without trovafloxacin or amphotericin B with or without trovafloxacin. Survival of mice treated with a suboptimal dose of amphotericin B (0.2 mg/kg/day) was also improved when trovafloxacin (40 mg/kg) given twice daily was included (0 versus 27%, respectively; P < 0.05). While the mechanisms of action of the combination of trovafloxacin and amphotericin B or fluconazole are unclear, further work focused on fungal topoisomerase inhibition and the mechanism of the antifungal effect of quinolone antibacterial drugs is warranted.

scholarly journals In Vitro Activity of Combinations of Zinc Chelators with Amphotericin B and Posaconazole against Six Mucorales Species

2019 ◽  
Vol 63 (5) ◽  
Author(s):  
Florencia Leonardelli ◽  
Daiana Macedo ◽  
Catiana Dudiuk ◽  
Laura Theill ◽  
Matias S. Cabeza ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Amphotericin B ◽  
High Mortality ◽  
Mortality Rates ◽  
Antifungal Drugs ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Therapy Strategies ◽  
Strain Dependent

ABSTRACT Mucormycosis is an emerging disease with high mortality rates. Few antifungal drugs are active against Mucorales. Considering the low efficacy of monotherapy, combination-therapy strategies have been described. It is known that fungi are susceptible to zinc deprivation, so we tested the in vitro effect of the zinc chelators clioquinol, phenanthroline, and N,N,N′,N′-tetrakis(2-pyridylmethyl)ethane-1,2-diamine combined with amphotericin B or posaconazole against 25 strains of Mucorales. Clioquinol-posaconazole was the most active combination, although results were strain dependent.

scholarly journals In Vitro Interactions of Approved and Novel Drugs against Paecilomyces spp

2004 ◽  
Vol 48 (7) ◽  
pp. 2727-2729 ◽  
Author(s):  
Montserrat Ortoneda ◽  
Javier Capilla ◽  
F. Javier Pastor ◽  
Isabel Pujol ◽  
Clara Yustes ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Antifungal Agents ◽  
Antifungal Drugs ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Paecilomyces Variotii ◽  
Novel Drugs ◽  
In Vitro Interactions

ABSTRACT We have evaluated the in vitro activity of 15 combinations of antifungal drugs (amphotericin B, itraconazole, voriconazole, albaconazole, ravuconazole, terbinafine, and micafungin) against four isolates of Paecilomyces variotii and three of P. lilacinus. The interaction of terbinafine with the four azoles was synergistic for 53% of the combinations, while the interactions of both amphotericin B and micafungin with the rest of antifungal agents were mainly indifferent.

In vitro activity of olorofim against clinical isolates of Scedosporium species and Lomentospora prolificans using EUCAST and CLSI methodologies

2020 ◽  
Vol 75 (12) ◽  
pp. 3582-3585
Author(s):  
Olga Rivero-Menendez ◽  
Manuel Cuenca-Estrella ◽  
Ana Alastruey-Izquierdo
Keyword(s):  
Amphotericin B ◽  
Susceptibility Testing ◽  
Antifungal Susceptibility ◽  
Vitro Activity ◽  
Clinical Isolates ◽  
Scedosporium Apiospermum ◽  
In Vitro Activity ◽  
Scedosporium Dehoogii ◽  
Scedosporium Species

Abstract Objectives To evaluate the in vitro activity of olorofim, a new broad-spectrum antifungal with a novel mechanism of action, against a collection of 123 Spanish clinical isolates belonging to five Scedosporium species and Lomentospora prolificans. Methods The activity of olorofim against Scedosporium apiospermum (n = 30), Scedosporium boydii (n = 30), Scedosporium ellipsoideum (n = 10), Scedosporium aurantiacum (n = 20), Scedosporium dehoogii (n = 3) and Lomentospora prolificans (n = 30) was compared with that of amphotericin B, voriconazole, isavuconazole and micafungin by performing EUCAST and CLSI reference methods for antifungal susceptibility testing. Results Amphotericin B and isavuconazole showed MICs ≥2 mg/L for all the species evaluated and voriconazole was moderately active (GM, MIC50 and MIC90 values ≤2 mg/L) against all of them except L. prolificans. Micafungin was effective against S. apiospermum complex strains, but exhibited elevated MECs for S. dehoogii and S. aurantiacum. Olorofim showed low MICs for all the Scedosporium strains tested (GM values were lower than 0.130 and 0.339 by the EUCAST method and the CLSI method, respectively, for all of the species), including those belonging to the MDR species L. prolificans, for which GM values were 0.115 and 0.225 mg/L by the EUCAST method and the CLSI method, respectively, while the GMs for the rest of the antifungals evaluated were higher than 3.732 mg/L using both methodologies. Conclusions Olorofim displayed promising in vitro activity against the Scedosporium and L. prolificans strains tested, some of which have reduced susceptibility to the antifungals that are currently in use.

scholarly journals In Vitro Activity of Nystatin Compared with Those of Liposomal Nystatin, Amphotericin B, and Fluconazole against Clinical Candida Isolates

2002 ◽  
Vol 40 (4) ◽  
pp. 1406-1412 ◽  
Author(s):  
S. Arikan ◽  
L. Ostrosky-Zeichner ◽  
M. Lozano-Chiu ◽  
V. Paetznick ◽  
D. Gordon ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Vitro Activity ◽  
In Vitro Activity

In vitro activity of voriconazole, itraconazole, caspofungin, anidulafungin (VER002, LY303366) and amphotericin B against aspergillus spp

2003 ◽  
Vol 45 (2) ◽  
pp. 131-135 ◽  
Author(s):  
María del Carmen Serrano ◽  
Anastasio Valverde-Conde ◽  
M.ónica Chávez ◽  
Samuel Bernal ◽  
Rosa María Claro ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Vitro Activity ◽  
In Vitro Activity

scholarly journals Comparison of In Vitro Activity of Liposomal Nystatin againstAspergillus Species with Those of Nystatin, Amphotericin B (AB) Deoxycholate, AB Colloidal Dispersion, Liposomal AB, AB Lipid Complex, and Itraconazole

1999 ◽  
Vol 43 (5) ◽  
pp. 1264-1266 ◽  
Author(s):  
Karen L. Oakley ◽  
Caroline B. Moore ◽  
David W. Denning
Keyword(s):  
Amphotericin B ◽  
Aspergillus Terreus ◽  
Antifungal Agents ◽  
Geometric Mean ◽  
Colloidal Dispersion ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Lipid Complex

ABSTRACT We compared the in vitro activity of liposomal nystatin (Nyotran) with those of other antifungal agents against 60Aspergillus isolates. Twelve isolates were itraconazole resistant. For all isolates, geometric mean (GM) MICs (micrograms per milliliter) were 2.30 for liposomal nystatin, 0.58 for itraconazole, 0.86 for amphotericin B (AB) deoxycholate, 9.51 for nystatin, 2.07 for liposomal AB, 2.57 for AB lipid complex, and 0.86 for AB colloidal dispersion. Aspergillus terreus (GM, 8.72 μg/ml; range, 8 to 16 μg/ml) was significantly less susceptible to all of the polyene drugs than all other species (P = 0.0001).

scholarly journals In vitro activity of a new echinocandin, LY303366, compared with those of amphotericin B and fluconazole against clinical yeast isolates.

1997 ◽  
Vol 41 (5) ◽  
pp. 1156-1157 ◽  
Author(s):  
O Uzun ◽  
S Kocagöz ◽  
Y Cetinkaya ◽  
S Arikan ◽  
S Unal
Keyword(s):  
Candida Albicans ◽  
Amphotericin B ◽  
Vitro Activity ◽  
In Vitro Activity ◽  
Broth Microdilution ◽  
Microdilution Method ◽  
Broth Microdilution Method

The in vitro activity of LY303366, a new echinocandin derivative, was evaluated with 191 yeast isolates by a broth microdilution method. The MICs at which 50% of the isolates were inhibited were 0.125 microg/ml for Candida albicans and C. tropicalis, 0.25 microg/ml for C. krusei, C. kefyr, and C. glabrata, and 2.0 microg/ml for C. parapsilosis.

scholarly journals Relationship between In Vitro Activities of Amphotericin B and Flucytosine and pH for Clinical Yeast and Mold Isolates

2005 ◽  
Vol 49 (8) ◽  
pp. 3341-3346 ◽  
Author(s):  
D. T. A. te Dorsthorst ◽  
P. E. Verweij ◽  
J. F. G. M. Meis ◽  
J. W. Mouton
Keyword(s):  
Amphotericin B ◽  
Phosphate Buffer ◽  
Vitro Activity ◽  
Nonlinear Relationship ◽  
In Vitro Activity ◽  
The Mean ◽  
Ph Range ◽  
Citrate Phosphate ◽  
Citrate Phosphate Buffer

ABSTRACT In this study, we investigated the pH dependency of the in vitro activities of amphotericin B (AMB) and flucytosine (5FC) against Candida spp., Cryptococcus neoformans, Aspergillus fumigatus, Rhizopus spp., and Scedosporium prolificans in RPMI 1640 buffered with citrate buffer (pH 4.0, 5.0, 5.4, and 6.0), citrate-phosphate buffer (pH 5.4, 6.0, 6.4, and 7.0), and 3-[N-morpholino]propanesulfonic acid (MOPS) (pH 6.4, 7.0, 7.4, and 7.9). For 5FC, no significant differences were found between MICs obtained with the different buffers, while for AMB, significant differences were found. The MICs obtained with citrate-phosphate buffer were approximately 1 twofold-dilution step higher than the MICs obtained with MOPS. We demonstrated that the in vitro activities of AMB and 5FC against yeast and mold isolates were pH dependent. The in vitro activity of AMB decreased when the pH was lowered, while the in vitro activity of 5FC increased. The effect of the pH on the in vitro activities was dependent not only on the antifungal agent tested but also on the microorganism. For AMB, there was a nonlinear relationship (median r 2, 0.864) for Candida spp., C. neoformans, A. fumigatus, and Rhizopus spp. over the pH range tested. The mean MICs ranged from 0.5 to 2.52 μg/ml at pH 7.0 and from 20.16 to 32 μg/ml at pH 5.0. For S. prolificans, there was no relationship. For 5FC, there was a linear relationship for Candida spp. (median r 2, 0.767) and a nonlinear relationship for C. neoformans and A. fumigatus (median r 2, 0.882) over the pH range tested. The mean MIC values ranged from 0.125 to 1,024 μg/ml at pH 7.0 and from 0.02 to 4 μg/ml at pH 5.0. For Rhizopus spp. and S. prolificans, the relationship could not be determined, since the MIC was >1,024 μg/ml over a pH range of 4.0 to 7.9.

Sign in / Sign up

Export Citation Format

Share Document