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A J Carrillo-Muñoz

Publications and source records attributed to A J Carrillo-Muñoz.

At least 19 recordsLinked to original sources
PubMed2006

In vitro antifungal susceptibility testing of filamentous fungi with Sensititre Yeast One.

Sensititre is a colorimetric microdilution method for in vitro antifungal susceptibility testing based on the M27-A document (National Committee for Clinical Laboratory Standards) for yeasts. Difference between both methods is the presence of Alamar-blue and RPMI 1640 (glucose 2%) as culture medium. Antifungal susceptibility to amphotericin B, fluconazole, itraconazole, ketoconazole and flucytosine, 100 opportunistic filamentous fungi (Aspergillus spp., Fusarium spp., Scedosporium spp.) obtained from pathological samples was determined by the Sensititre method. Induction to conidium and sporangiospore formation at 35 degrees C was used to get inoculum and plates were covered by 1 ml of saline and suspensions were made by gently probing by a sterile loop. Optical densities of the conidial suspensions were adjusted to 80-82% transmittance for Aspergillus spp. and 68-70% for the rest of strains tested. Final inoculum concentration size was 0.4 x 10(4)-5 x 10(4) CFU ml(-1). Readings were made at 72 h of incubation at 35 degrees C; amphotericin B and itraconazole was active against Aspergillus fumigatus with CMI90 1 and 0.5 microg ml(-1), respectively, opposite to Scedosporium prolificans and Scedosporium apiospermum. As it was expected, a CMI90 of 256 microg ml(-1) for fluconazole and CMI90 for flucytosine amounting to 64 g ml(-1) were obtained. Sensititre Yeast One is a useful method and an alternative to reference methods to determine antifungal susceptibility of filamentous fungi for clinical laboratory routine. Correlation with microdilution results is studied. New triazole derivatives should be included as soon as their clinical use will be feasible.

Amphotericin B↗
PubMed2006

Antifungal agents: mode of action in yeast cells.

Different kinds of mycoses, especially invasive, have become an important public health problem as their incidence has increased dramatically in the last decades in relation to AIDS, hematological malignancies, transplant recipients and other immunosuppressed individuals. Management of fungal infections is markedly limited by problems of drug safety, resistance and effectiveness profile. Current therapy for invasive mycoses uses a relatively reduced number of antifungal drugs, such as amphotericin B, fluconazole and itraconazole. Other new antifungal agents from old and new chemical families, like voriconazole, posaconazole, ravuconazole, caspofungin and micafungin, have been introduced into the armamentarium for fungal infections management. This review is focused on the mode of action of those antifungal drugs used against pathogenic yeasts. The interaction of amphotericin B with ergosterol and other membrane sterols results in the production of aqueous pores of drug and the ergosterol biosynthetic pathway is the target of the allylamines, phenylmorpholines and azole antifungal agents. The main molecular target of azole antifungals is the cytochrome P-450 protein Erg11p/Cyp51p. Echinocandins, a new class of antifungal drugs, are fungal secondary metabolites that act against beta-1-3-D-glucan synthesis. The phenylmorpholines, of which amorolfine is the sole representative in human therapy, affect two targets in the ergosterol pathway: Erg24p (delta 14 reductase) and Erg2p (delta 8-delta 7 isomerase). The sordarins group are protein synthesis inhibitors that work by blocking the function of fungal translation elongation factor 2. Other protein inhibitors are zofimarin, BE31045, SCH57504, xylarin, hypoxysordarin and GR135402. In order to overcome the problems derived from the exploitation of azole drugs, macrolides and echinocandins, novel targets were explored. Proposed antifungal drugs have been developed against potential targets like the N-myristylation of fungal proteins, with inhibitors like myristate and histidine analogues or myristoylpeptide derivatives, aminobenzothiazoles, quinolines and benzofurans. Polymerization of cell wall carbohydrates from uridine di-phospho sugars is another potential target.

Antifungal Agents↗
PubMed2004

In vitro antifungal activity of sertaconazole compared with nine other drugs against 250 clinical isolates of dermatophytes and Scopulariopsis brevicaulis.

We have tested 250 strains belonging to 15 species of clinically important dermatophytes and Scopulariopsis against ten antifungal drugs using an agar diffusion method (NeoSensitabstrade mark, Rosco, Taastrup, Denmark). Some of the experimental factors were adapted to dermatophyte development, such as temperature (28 vs. 35 degrees C) and time of incubation (2-5 days vs. 21-74 h). The antifungals used are itraconazole, ketoconazole, miconazole, clotrimazole, sertaconazole, terbinafine, tioconazole, fluconazole, isoconazole and econazole. Except for fluconazole, all the drugs tested have shown to be highly effective, especially sertaconazole and terbinafine. Percentages of susceptibility ranged between 94% for terbinafine, 87.6% for sertaconazole and 86.4% clotrimazole; 81.6% econazole; 42.8% fluconazole; 57.2% isoconazole; 78.4% itraconazole; 74.4% ketoconazole; 73.3% miconazole, and 85.2% for tioconazole. Percentages of resistance were similar between sertaconazole and terbinafine (4%) but in contrast to the 48% obtained for fluconazole.

Antifungal Agents↗
PubMed2004

Comparative evaluation of four commercial tests for presumptive identification of Candida albicans.

Four commercially available tests (Albicans ID2, Chromalbicans Agar, CHROMagar Candida, and BactiCard Candida) and the germ tube (GT) test for presumptive identification of Candida albicans were evaluated using clinical isolates of C. albicans (n=89) and of non-albicans yeasts (n=107). Sensitivities and specificities of all tests regarding the identification of C. albicans were greater than 92%, except for Chromalbicans Agar plates (88.7% after 48 h) and their specificity was 86%. Overall, the four commercial systems were easy to use and are good systems for the routine identification of C. albicans.

Candida albicans↗
PubMed2004

Antifungal activity of amphotericin B and itraconazole against filamentous fungi: comparison of the Sensititre Yeast One and NCCLS M38--a reference methods.

The susceptibilities of 81 clinical isolates of Aspergillus spp., Fusarium spp., and Scedosporium spp., to amphotericin B and itraconazole were determined by the colorimetric microdilution method Sensititre and the reference microdilution method of NCCLS standard M38-A for filamentous fungi. No major discrepancies were found and agreement ranged between 86.4% to 84% and 69.1% to 86.4% for amphotericin B and itraconazole respectively at 48 h and 72 h of incubation by using the recommended endpoints. Within two two-fold dilutions, high levels of agreement were found in general for amphotericin B at 48 or 72 h (86.4 to 87.7%) and itraconazole (91.4 to 93.8%). Relatively better agreement was found for itraconazole at 72 h of incubation and 48 for amphotericin B.

Amphotericin B↗
PubMed2004

[Is amphotericin B active against dermatophytes and Scopulariopsis brevicaulis?].

The in vitro antifungal activity of amphotericin B was compared with that of griseofulvin, ketoconazole, clotrimazole and terbinafine in 193 clinical isolates of dermatophytes and Scopulariopsis brevicaulis. An agar diffusion method was used (NeoSensitabs) to categorize the susceptibility of the isolates as susceptible, intermediate or resistant to the antifungal agents. Using this method and following a standardized protocol adapted to the growth conditions of the dermatophytes and the opportunistic mold S. brevicaulis (inoculum size, temperature and time period of incubation), it was found that the in vitro susceptibility rates were 72%, 94.3%, 81.9%, 72% and 86% for amphotericin B, terbinafine, griseofulvin, ketoconazole and clotrimazole, respectively. Resistance percentages were 12.4%, 3.6%, 18.1%, 10.4% and 4.1% for the same antifungal agents. Amphotericin B showed no antifungal activity against S. brevicaulis; its activity against dermatophytes was similar to that of ketoconazole, and lower than that for clotrimazole and terbinafine.

Amphotericin B↗
PubMed2003

Performance of Bacticard Candida compared with the germ tube test for the presumptive identification of Candida albicans.

Bacticard Candida was compared with the germ tube test for the rapid, presumptive identification of Candida albicans. This test kit detects the enzymatic activities l-proline aminopeptidase and beta-galactosaminidase in yeast colonies grown on culture media. Candida albicans produces both enzymes whereas other yeasts produce only one or neither of the enzymes. We evaluated 536 isolates including eight genera and 33 species of medically important yeasts, including 228 C. albicans and 36 C. dubliniensis. Both tests did not discriminate between C. albicans and C. dubliniensis isolates. The sensitivity and specificity for the Bacticard Candida test were 97.8 and 96.5%, respectively. Bacticard Candida and germ tube tests detected 246 (93.2%), and 256 (97%) C. albicans plus C. dubliniensis isolates. There were eight false-positive results with BactiCard Candida kit and four false-positive results with the germ tube test. Positive and negative predictive values for Bacticard Candida enzymatic test were 95.3 and 98.4%, respectively, while 97.4 and 98.1% for the germ tube test, its specificity being 98.1% and efficiency 97% (97.7% for germ tube). We have observed slightly lower values of sensitivity and specificity than those reported by others using the BactiCard test kit. Bacticard Candida provides a rapid and accurate alternative to the germ tube test for the presumptive identification of C. albicans.

Aminopeptidases↗
PubMed2003

In vitro activity of sertaconazole against dermatophyte isolates with reduced fluconazole susceptibility.

We have studied the in vitro antifungal activity of sertaconazole against 114 dermatophytes with low susceptibility to fluconazole following the National Committee for Clinical Laboratory Standards for filamentous fungi (M38-P). However, several important factors such as the temperature (28 vs. 35 degrees C) and time of incubation (4-10 days vs. 21-74 h), have been found to affect dermatophytes. Isolates were recently recovered from human samples. Sertaconazole was active against 114 isolates of 12 fungal dermatophyte species, showing an overall geometric mean of 0.41 microg/ml with a minimum inhibitory concentration (MIC) range of 0.01-2 microg/ml against these isolates with reduced fluconazole susceptibility. Differences between both antifungals were significant (p < 0.05). MIC(50) and MIC(90) of sertaconazole were of 0.5 and 1 microg/ml, respectively, while the MIC of fluconazole was >/=16 microg/ml. None of the isolates was resistant to sertaconazole during the study while for four isolates the MIC of fluconazole was >/=64 microg/ml. No evidence of cross-resistance between both antifungals was found.

Antifungal Agents↗
PubMed2003

In vitro antifungal activity of sertaconazole against 309 dermatophyte clinical isolates.

Three hundred and nine strains belonging to 11 species of dermatophyte moulds were tested against sertaconazole following mainly the National Committee for Clinical Laboratory Standards (M38-P) for filamentous fungi. However, several important factors such as the temperature (28 degrees C vs 35 degrees C) and time of incubation (4-10 d vs 21-74 h), have been modified. Sertaconazole was active against all the clinically important dermatophyte moulds involved in human infections tested. Overall geometric mean MIC of sertaconazole was 0.21 microg/ml with a MIC range of 0.01-8 microg/ml. MIC50 and MIC90 were respectively of 0.25 and 1 microg/ml. Sertaconazole was very active against Epidermophyton floccosum, Trichophyton rubrum, Trichophyton tonsurans and Microsporum canis (geometric means 0.08, 0.13, 0.13 and 0.19 microg/ml respectively). Microsporum audouinii had the lowest susceptibility in the study (geometric mean 0.59 microg/ml). Considering MIC50 and MIC90 these differences were significantly in favor of the activity of sertaconazole against E. floccosum (0.06 and 0.5 microg/ml respectively).

Antifungal Agents↗
PubMed2001

Sertaconazole: in-vitro antifungal activity against vaginal and other superficial yeast isolates.

The in vitro susceptibilities of 183 clinical yeast isolates to sertaconazole (STZ) were compared to their susceptibilities to clotrimazole (CTZ), econazole (ECZ), ketoconazole (KTZ), miconazole (MNZ), fluconazole (FLZ), itraconazole (ITZ), tioconazole (TCZ), amphotericin B (AMB) and flucytosine (5FC) by using a commercial agar diffusion method. Strains were isolated from vaginal and other superficial clinical samples (18 species of Candida and five strains belonging to other yeast genera). Only one strain (0.5%) was resistant to STZ out of 87.4% of susceptible strains (n=160). The percentage of susceptible strains was higher than those obtained with the other agents evaluated and the percentage of resistant strains was lower than for most of the other antifungals. The pattern of susceptibility of C. albicans to STZ, TCZ, ITZ and CLZ was similar and superior to the pattern of susceptibility of this species to MNZ, ECZ, FLZ, 5FC and KTZ. C. dubliniensis was more susceptible to STZ, MNZ, MNZ, FLZ, ITZ, CLZ than to TCZ, ECZ, 5FC, AMB or KTZ. Ten susceptible strains to STZ were resistant to FLZ and one strain was resistant to ITZ. The overall antifungal activity of STZ in vitro against a wide range of clinically important yeasts from vaginal and cutaneous samples indicates the therapeutic potential of this agent for the treatment of infections caused by these fungi. However, the activity of STZ and the clinical value of in vitro data need to be verified in human clinical trials.

Anti-Bacterial Agents↗
PubMed2001

[Activity of itraconazole against clinical isolates of Aspergillus spp. and Fusarium spp. determined by the M38-P NCCLS method].

The antifungal activity of itraconazole was studied in 101 clinical isolates of Aspergillus fumigatus, A. flavus, A. niger, A. terreus, A. nidulans, A. candidus, A. glaucus, A. clavatus, Fusarium solani, F. oxysporum and F. semitectum. The minimum inhibitory concentrations (MIC) were determined according to the protocol of the M38-P National Committee for Laboratory Standards (NCCLS) document using a microdilution method in 1640 RPMI liquid medium (visual reading at 48 and 72 h incubation). In general, the MIC did not vary with time of incubation, except in a Z. fumigatus strain in which the MIC went from 2 to 16 mg/l. The geometric mean of the MIC and MIC(90) of itraconazole for Aspergillus spp. was 0.44 mg/l and 0.5 mg/l, respectively; and for Fusarium spp. it was 14.1 mg/l and 16 mg/l, respectively. With 0.5 mg/l 75% of the Aspergillus spp. strains were inhibited, and 100% of these strains were inhibited with 2 mg/l. A. niger and A. fumigatus were the most resistant species (MIC(90) 2 mg/l). The MIC of all the Fusarium strains essayed was between 4 and 16 mg/l.

Antifungal Agents↗
PubMed2001

[Evaluation of Chromalbicans Agar for presumptive identification of Candida albicans].

The utility of Chromalbicans Agar (Biolife Italiana, Milano, Italy) was evaluated with 723 clinical isolates and type culture collection strains from different genera including Candida, Cryptococcus, Pichia, Rhodotorula, Saccharomyces, Trichosporon y Zygosaccharomyces. Presumptive identification was confirmed by germ tube test and carbohydrate assimilation on API-ATB ID 32C (bioMerieux, France). Growth on Chromalbicans Agar was very useful for the presumptive identification of C. albicans isolates, and sensitivity and specificity values were significantly high (>97%), since a very low number of isolates were found to be false negative or false positive.

English Abstract↗
PubMed2000

Emerging pathogens.

The ever increasing numbers of immunosuppressed individuals has led to a significant increase in the incidence of opportunistic infections, particularly those caused by fungi. The epidemiology of infections caused by the common fungal pathogens such as Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus has been well documented. However, in addition to these, a number of species which have previously been unrecognized (e.g., C. dubliniensis) or have previously been assumed to be non-pathogenic (e.g., Saccharomyces cerevisiae, Scedosporium spp. and Fusarium spp.) have emerged as agents of human disease. Since these species have only been identified recently as human pathogens, their role in disease is poorly understood. In most cases, identification of these species is problematic and therefore their epidemiology has yet to be elucidated adequately. In addition, several of these species fail to respond to conventional antifungal therapies. In this article, we describe the emergence of two separate yeast species (C. dubliniensis and S. cerevisiae) and two separate groups of moulds (Scedosporium prolificans and Fusarium spp.), as human pathogens. It is apparent from what we already know, that much work has yet to be performed before we have a clear understanding of how these species cause disease and most importantly how they can be controlled.

Candida↗
PubMed2000

[In vitro activity of a liposomal nystatin formulation (Nyotran) against Cryptococcus neoformans].

The in vitro antifungal activity of a new liposomal nystatin formulation (NISTL, Nyotran, Aronex Ltd., EE.UU.) was evaluated by a microdilution method with RPMI based on the M27A document of the National Committee for Clinical Laboratory Standards (NCCLS) against 22 isolates of Cryptococcus neoformans. This antifungal activity was compared with those of other seven antifungal agents, such as nystatin (NIST), amphotericin B deoxycholate, liposomal amphotericin B, amphotericin B lipid complex, amphotericin B colloidal dispersion, fluconazole, and itraconazole. NISTL was more active in vitrothan NIST, showing MIC values 2-3 fold smaller in 90% of the isolates. The results obtained suggest that this new formulation would be very helpful for the treatment of cryptococcosis.

English Abstract↗
PubMed1999

In-vitro antifungal activity of liposomal nystatin in comparison with nystatin, amphotericin B cholesteryl sulphate, liposomal amphotericin B, amphotericin B lipid complex, amphotericin B desoxycholate, fluconazole and itraconazole.

The in-vitro susceptibilities of 120 clinical isolates of yeasts to liposomal nystatin were compared with those to amphotericin B lipid complex (ABLC), liposomal amphotericin B (LAB), amphotericin B cholesteryl sulphate (ABCD), amphotericin B desoxycholate, nystatin, fluconazole and itraconazole. Yeast isolates examined included strains of Candida albicans, Candida parapsilosis, Candida glabrata, Candida krusei, Candida guilliermondii, Candida tropicalis, Candida kefyr, Candida viswanathii, Candida famata, Candida rugosa, Rhodotorula rubra, Trichosporon spp., Cryptococcus laurentii and Cryptococcus neoformans. The mean MICs for all strains examined were: liposomal nystatin 0.96 mg/L; nystatin 0.54 mg/L; ABLC 0.65 mg/L; LAB 1.07 mg/L; ABCD 0.75 mg/L; amphotericin B 0.43 mg/L; fluconazole 5.53 mg/L; and itraconazole 0.33 mg/L. No significant differences were seen between the activity of liposomal nystatin and the polyene drugs or itraconazole, but liposomal nystatin was more active than fluconazole. MICs were lower than the reported blood concentrations following therapeutic doses of this drug, indicating the potential for a therapeutic use of liposomal nystatin in humans. These results indicate good activity in vitro against medically important yeasts, which compares favourably with the activities of other currently available antifungal drugs. Liposomal nystatin may have a role in the treatment of disseminated and systemic mycoses.

Amphotericin B↗