RESUMEN
Vulvovaginal candidiasis (VVC) is an opportunistic infection caused by a fungus of the Candida genus, affecting approximately 75 % of women during their lifetime. Fungal resistance cases and adverse effects have been the main challenges of oral therapies. In this study, the topical application of thin films containing fluconazole (FLU) and thymol (THY) was proposed to overcome these problems. Vaginal films based only on chitosan (CH) or combining this biopolymer with pectin (PEC) or hydroxypropylmethylcellulose acetate succinate (HPMCAS) were developed by the solvent casting method. In addition to a higher swelling index, CH/HPMCAS films showed to be more plastic and flexible than systems prepared with CH/PEC or only chitosan. Biopolymers and FLU were found in an amorphous state, contributing to explaining the rapid gel formation after contact with vaginal fluid. High permeability rates of FLU were also found after its immobilization into thin films. The presence of THY in polymer films increased the distribution of FLU in vaginal tissues and resulted in improved anti-Candida activity. A significant activity against the resistant C. glabrata was achieved, reducing the required FLU dose by 50 %. These results suggest that the developed polymer films represent a promising alternative for the treatment of resistant vulvovaginal candidiasis, encouraging further studies in this context.
Asunto(s)
Antifúngicos , Candidiasis Vulvovaginal , Fluconazol , Timol , Femenino , Candidiasis Vulvovaginal/tratamiento farmacológico , Candidiasis Vulvovaginal/microbiología , Fluconazol/farmacología , Fluconazol/química , Fluconazol/administración & dosificación , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/administración & dosificación , Biopolímeros/química , Timol/química , Timol/farmacología , Farmacorresistencia Fúngica/efectos de los fármacos , Humanos , Quitosano/química , Pruebas de Sensibilidad Microbiana , Animales , Portadores de Fármacos/química , Permeabilidad , Candida glabrata/efectos de los fármacosRESUMEN
BACKGROUND: Extensive antifungal drug use has enhanced fungal resistance, resulting in persistent mycoses. Combining antifungal plant extracts/compounds with these drugs offers good alternatives to increase the activity of both partners, minimize side effects, and overcome drug resistance. In our previous study, Phytolacca tetramera berries extracts demonstrated activity against Candida spp., correlating with the amount of the main constituent phytolaccoside B and its genin, phytolaccagenin. The extracts and phytolaccagenin altered the fungal plasma membrane by binding to ergosterol, whereas phytolaccoside B increased chitin synthase activity. However, the presence of triterpenoid saponins in Phytolacca spp. has been linked to acute toxicity in humans. PURPOSE: This study aimed to evaluate combinations of P. tetramera berries extracts, phytolaccoside B and phytolaccagenin, together with commercial antifungals [amphotericin B, fluconazole, itraconazole, posaconazole, and caspofungin] against Candida albicans and Candida glabrata, to find synergistic effects with multi-target actions, in which the doses of both partners are reduced, and therefore their toxicity. Additionally, we intended to explore their anti-virulence capacity, thereby hindering the development of drug-resistant strains. METHODS: The effects of these combinations were evaluated using both the checkerboard and isobologram methods. Fractional Inhibitory Concentration Index and Dose Reduction Index were calculated to interpret the combination results. To confirm the multi-target effect, studies on mechanisms of action of synergistic mixtures were performed using ergosterol-binding and quantification assays. The ability to inhibit Candida virulence factors, including biofilm formation and eradication from inert surfaces, was also evaluated. Quantification of active markers was performed using a validated UHPLC-ESI-MS method. RESULTS: Eight synergistic combinations of P. tetramera extracts or phytolaccagenin (but not phytolaccoside B) with itraconazole or posaconazole were obtained against C. albicans, including a resistant strain. These mixtures acted by binding to ergosterol, decreasing its whole content, and inhibiting Candida biofilm formation in 96-well microplates and feeding tubes in vitro, but were unable to eradicate preformed biofilms. CONCLUSIONS: This study demonstrated the synergistic and anti-virulence effects of P. tetramera berries extracts and phytolaccagenin with antifungal drugs against Candida spp., providing novel treatment avenues for fungal infections with reduced doses of both natural products and commercial antifungals, thereby mitigating potential human toxicity concerns.
Asunto(s)
Antifúngicos , Candida albicans , Sinergismo Farmacológico , Frutas , Pruebas de Sensibilidad Microbiana , Phytolacca , Extractos Vegetales , Antifúngicos/farmacología , Antifúngicos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Frutas/química , Candida albicans/efectos de los fármacos , Phytolacca/química , Candida glabrata/efectos de los fármacos , Saponinas/farmacología , Candida/efectos de los fármacosRESUMEN
OBJECTIVES: To incorporate the nanostructured silver vanadate decorated with silver nanoparticles (AgVO3) into denture base materials: heat-cured (HC) and 3D printed (3DP) resins, at concentrations of 2.5 %, 5 %, and 10 %; and to evaluate the antimicrobial activity in two multi-species biofilm: (1) Candida albicans, Candida glabrata, and Streptococcus mutans, (2) Candida albicans, Pseudomonas aeruginosa, and Staphylococcus aureus, and the wettability. METHODS: The AgVO3 was added to the HC powder, and printed samples were coated with 3DP with AgVO3 incorporated. After biofilm formation, the antimicrobial activity was evaluated by colony forming units per milliliter (CFU/mL), metabolic activity, and epifluorescence microscopy. Wettability was assessed by the contact angles with water and artificial saliva. RESULTS: In biofilm (1), HC-5 % and HC-10 % showed activity against S. mutans, HC-10 % against C. glabrata, and HC-10 % and 3DP-10 % had higher CFU/mL of C. albicans. 3DP-5 % had lower metabolic activity than the 3DP control. In biofilm (2), HC-10 % reduced S. aureus and P. aeruginosa, and HC-5 %, 3DP-2.5 %, and 3DP-5 % reduced S. aureus. 3DP incorporated with AgVO3, HC-5 %, and HC-10 % reduced biofilm (2) metabolic activity. 3DP-5 % and 3DP-10 % increased wettability with water and saliva. CONCLUSION: HC-10 % was effective against C. glabrata, S. mutans, P. aeruginosa, and S. aureus, and HC-5 % reduced S. mutans and S. aureus. For 3DP, 2.5 % and 5 % reduced S. aureus. The incorporation of AgVO3 into both resins reduced the metabolic activity of biofilms but had no effect on C. albicans. The wettability of the 3DP with water and saliva increased with the addition of AgVO3. CLINICAL SIGNIFICANCE: The incorporation of silver vanadate into the denture base materials provides antimicrobial efficacy and can prevent the aggravation of oral and systemic diseases. The incorporation of nanomaterials into printed resins is challenging and the coating is an alternative to obtain the inner denture base with antimicrobial effect.
Asunto(s)
Biopelículas , Candida albicans , Bases para Dentadura , Nanopartículas del Metal , Pseudomonas aeruginosa , Plata , Staphylococcus aureus , Streptococcus mutans , Vanadatos , Humectabilidad , Biopelículas/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Candida albicans/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Vanadatos/farmacología , Vanadatos/química , Pseudomonas aeruginosa/efectos de los fármacos , Plata/farmacología , Plata/química , Bases para Dentadura/microbiología , Nanopartículas del Metal/química , Antiinfecciosos/farmacología , Candida glabrata/efectos de los fármacos , Impresión Tridimensional , Ensayo de Materiales , Humanos , Nanoestructuras , Compuestos de Plata/farmacología , Compuestos de Plata/química , Materiales Dentales/química , Materiales Dentales/farmacologíaRESUMEN
Candida glabrata (Nakaseomyces glabrata) is an emergent and opportunistic fungal pathogen that colonizes and persists in different niches within its human host. In this work, we studied five clinical isolates from one patient (P7), that have a clonal origin, and all of which come from blood cultures except one, P7-3, obtained from a urine culture. We found phenotypic variation such as sensitivity to high temperature, oxidative stress, susceptibility to two classes of antifungal agents, and cell wall porosity. Only isolate P7-3 is highly resistant to the echinocandin caspofungin while the other four isolates from P7 are sensitive. However, this same isolate P7-3, is the only one that displays susceptibility to fluconazole (FLC), while the rest of the isolates are resistant to this antifungal. We sequenced the PDR1 gene which encodes a transcription factor required to induce the expression of several genes involved in the resistance to FLC and found that all the isolates encode for the same Pdr1 amino acid sequence except for the last isolate P7-5, which contains a single amino acid change, G1099C in the putative Pdr1 transactivation domain. Consistent with the resistance to FLC, we found that the CDR1 gene, encoding the main drug efflux pump in C. glabrata, is highly overexpressed in the FLC-resistant isolates, but not in the FLC-sensitive P7-3. In addition, the resistance to FLC observed in these isolates is dependent on the PDR1 gene. Additionally, we found that all P7 isolates have a different proportion of cell wall carbohydrates compared to our standard strains CBS138 and BG14. In P7 isolates, mannan is the most abundant cell wall component, whereas ß-glucan is the most abundant component in our standard strains. Consistently, all P7 isolates have a relatively low cell wall porosity compared to our standard strains. These data show phenotypic and genotypic variability between clonal isolates from different niches within a single host, suggesting microevolution of C. glabrata during an infection.
Asunto(s)
Antifúngicos , Candida glabrata , Farmacorresistencia Fúngica , Proteínas Fúngicas , Pruebas de Sensibilidad Microbiana , Candida glabrata/genética , Candida glabrata/efectos de los fármacos , Antifúngicos/farmacología , Humanos , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fluconazol/farmacología , Pared Celular/genética , Pared Celular/efectos de los fármacos , Candidiasis/microbiología , Caspofungina/farmacología , Evolución Molecular , Estrés Oxidativo/genética , Equinocandinas/farmacología , Factores de Transcripción/genéticaRESUMEN
Alternatives have been sought to add an antimicrobial property to denture adhesives. This study evaluated the antimicrobial potential of adhesives associated with nanostructured silver vanadate decorated with silver nanoparticles (ß-AgVO3). Specimens in acrylic resin were treated with the adhesives associated with ß-AgVO3 (1%, 2.5%, 5% and 10%). As control, specimens treated only with Ultra Corega Cream (UCC) or Ultra Corega Powder (UCP) adhesive were used. Multispecies biofilm of Candida albicans, Candida glabrata, Streptococcus mutans and Staphylococcus aureus was evaluated by counting colony forming units per milliliter (CFU/mL), colorimetric assay and fluorescence microscopy. The data were analyzed using the two-way analysis of variance (ANOVA) and Bonferroni multiple comparisons test (α=0.05). For both adhesives, a small amount of ß-AgVO3 (1%) completely inhibited S. mutans (P⟨0.05). For the other microorganisms, there was a reduction in metabolic activity and complete inhibition in the groups with intermediate or greater amounts of nanomaterial (P⟨0.05), except for C. albicans, which was reduced (P⟨0.05) but not completely inhibited in UCP. Microscopy that showed less biofilm in the groups with ß-AgVO3 and in the UCC than UCP. Denture adhesives in powder and cream form with ß-AgVO3 showed potential antimicrobial activity against multispecies biofilm. Powder adhesive showed higher biofilm formation.
Asunto(s)
Resinas Acrílicas , Biopelículas , Candida albicans , Plata , Streptococcus mutans , Vanadatos , Biopelículas/efectos de los fármacos , Vanadatos/farmacología , Vanadatos/química , Streptococcus mutans/efectos de los fármacos , Candida albicans/efectos de los fármacos , Plata/farmacología , Plata/química , Staphylococcus aureus/efectos de los fármacos , Antiinfecciosos/farmacología , Nanopartículas del Metal , Propiedades de Superficie , Cementos Dentales/farmacología , Compuestos de Plata/farmacología , Candida glabrata/efectos de los fármacosRESUMEN
Candida albicans is the most commonly implicated agent in invasive human fungal infections. The disease could be presented as minimal symptomatic candidemia or can be fulminant sepsis. Candidemia is associated with a high rate of mortality and high healthcare and hospitalization costs. The surveillance programs have reported the distribution of other Candida species reflecting the trends and antifungal susceptibilities. Previous studies have demonstrated that C. glabrata more frequently presents fluconazole-resistant strains. Extracts from Mexican plants have been reported with activity against pulmonary mycosis, among them Colubrina greggii. In the present study, extracts from the aerial parts (leaves, flowers, and fruits) of this plant were evaluated against clinical isolates of several species of Candida (C. albicans, C. glabrata, C. parapsilosis, C. krusei, and C. tropicalis) by the broth microdilution assay. Through bioassay-guided fractionation, three antifungal glycosylated flavonoids were isolated and characterized. The isolated compounds showed antifungal activity only against C. glabrata resistant to fluconazole, and were non-toxic toward brine shrimp lethality bioassay and in vitro Vero cell line assay. The ethyl acetate and butanol extracts, as well as the fractions containing the mixture of flavonoids, were more active against Candida spp.
Asunto(s)
Antifúngicos/farmacología , Candida glabrata/efectos de los fármacos , Candida/efectos de los fármacos , Colubrina/química , Flavonoides/farmacología , Animales , Antifúngicos/química , Artemia/efectos de los fármacos , Candida/aislamiento & purificación , Chlorocebus aethiops , Farmacorresistencia Fúngica/efectos de los fármacos , Flavonoides/química , Flavonoides/aislamiento & purificación , Fluconazol/farmacología , Glicosilación , Pruebas de Sensibilidad Microbiana , Fitoquímicos/química , Fitoquímicos/farmacología , Componentes Aéreos de las Plantas/química , Pruebas de Toxicidad , Células VeroRESUMEN
The most common nosocomial fungal infections are caused by several species of Candida, of which Candida glabrata is the second most frequently isolated species from bloodstream infections. C. glabrata displays relatively high minimal inhibitory concentration values (MIC) to the antifungal fluconazole and is associated with high mortality rates. To decrease mortality rates, the appropriate treatment must be administered promptly. C. glabrata contains in its genome several non-identical copies of species-specific sequences. We designed three pairs of C. glabrata-specific primers for endpoint PCR amplification that align to these species-specific sequences and amplify the different copies in the genome. Using these primers, we developed a fast, sensitive, inexpensive, and highly specific PCR-based method to positively detect C. glabrata DNA in a concentration-dependent manner from mixes of purified genomic DNA of several Candida species, as well as from hemocultures and urine clinical samples. This tool can be used for positive identification of C. glabrata in the clinic.
Asunto(s)
Candida glabrata , Reacción en Cadena de la Polimerasa , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Candida glabrata/efectos de los fármacos , Candida glabrata/genética , Candidiasis/diagnóstico , Candidiasis/microbiología , Cartilla de ADN , Fluconazol/farmacología , Humanos , Pruebas de Sensibilidad MicrobianaRESUMEN
Aim: Melanin has been linked to pathogenesis in several fungi. They often produce melanin-like pigments in the presence of L-dihydroxyphenylalanine (L-DOPA), but this is poorly studied in Candida glabrata. Methods & materials:C. glabrata was grown in minimal medium with or without L-DOPA supplementation and submitted to a chemical treatment with denaturant and hot acid. Results:C. glabrata turned black when grown in the presence of L-DOPA, whereas cells grown without L-DOPA supplementation remained white. Biophysical properties demonstrated that the pigment was melanin. Melanized C. glabrata cells were effectively protected from azoles and amphotericin B, incubation at 42°C and macrophage killing. Conclusion: In the presence of L-DOPA, C. glabrata produces melanin, increases antifungal resistance and enhances host survival.
Aim: Melanin is a pigment that can help fungi to cause disease. Fungi often produce melanin-like pigments in the presence of L-dihydroxyphenylalanine (L-DOPA), but this is poorly studied in Candida glabrata, a yeast species that can cause human disease. Methods & materials:C. glabrata was grown in minimal medium with or without L-DOPA supplementation and submitted to a chemical treatment to isolate melanin. Results:C. glabrata turned black when grown in the presence of L-DOPA, whereas cells grown without L-DOPA supplementation remained white. Several experiments demonstrated that the black pigment was melanin. Melanized C. glabrata cells were effectively protected from antifungal drugs, incubation at 42°C and killing by cells of the immune system. Conclusion: In the presence of L-DOPA, C. glabrata produces melanin, increases antifungal resistance and has enhanced survival in contact with immunologic defense cells.
Asunto(s)
Candida glabrata/patogenicidad , Candidiasis/microbiología , Melaninas/metabolismo , Anfotericina B/farmacología , Animales , Antifúngicos/farmacología , Azoles/farmacología , Candida glabrata/efectos de los fármacos , Candida glabrata/metabolismo , Candidiasis/inmunología , Citocinas/metabolismo , Dihidroxifenilalanina/metabolismo , Farmacorresistencia Fúngica , Macrófagos/inmunología , Ratones , Viabilidad Microbiana , VirulenciaRESUMEN
After Candida albicans, Candida glabrata is one of the most common fungal species associated with candidemia in nosocomial infections. Rapid acquisition of nutrients from the host is important for the survival of pathogens which possess the metabolic flexibility to assimilate different carbon and nitrogen compounds. In Saccharomyces cerevisiae, nitrogen assimilation is controlled through a mechanism known as Nitrogen Catabolite Repression (NCR). NCR is coordinated by the action of four GATA factors; two positive regulators, Gat1 and Gln3, and two negative regulators, Gzf3 and Dal80. A mechanism in C. glabrata similar to NCR in S. cerevisiae has not been broadly studied. We previously showed that in C. glabrata, Gln3, and not Gat1, has a major role in nitrogen assimilation as opposed to what has been observed in S. cerevisiae in which both factors regulate NCR-sensitive genes. Here, we expand the knowledge about the role of Gln3 from C. glabrata through the transcriptional analysis of BG14 and gln3Δ strains. Approximately, 53.5% of the detected genes were differentially expressed (DEG). From these DEG, amino acid metabolism and ABC transporters were two of the most enriched KEGG categories in our analysis (Up-DEG and Down-DEG, respectively). Furthermore, a positive role of Gln3 in AAA assimilation was described, as was its role in the transcriptional regulation of ARO8. Finally, an unexpected negative role of Gln3 in the gene regulation of ABC transporters CDR1 and CDR2 and its associated transcriptional regulator PDR1 was found. This observation was confirmed by a decreased susceptibility of the gln3Δ strain to fluconazole.
Asunto(s)
Aminoácidos/biosíntesis , Candida glabrata/fisiología , Farmacorresistencia Fúngica/genética , Fluconazol/metabolismo , Factores de Transcripción GATA/metabolismo , Transportadoras de Casetes de Unión a ATP/genética , Compuestos de Amonio/metabolismo , Antifúngicos/metabolismo , Antifúngicos/farmacología , Candida glabrata/efectos de los fármacos , Candida glabrata/genética , Candida glabrata/metabolismo , Represión Catabólica , Farmacorresistencia Fúngica/efectos de los fármacos , Fluconazol/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Factores de Transcripción GATA/genética , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , MutaciónRESUMEN
Candida spp. cause invasive fungal infections. One species, Candida glabrata, may present intrinsic resistance to conventional antifungal agents, thereby increasing mortality rates in hospitalized patients. In this context, metal complexes present an alternative for the development of new antifungal drugs owing to their biological and pharmacological activities demonstrated in studies in the last decades. Accordingly, in this study we have synthesized and characterized two new Co(II) complexes with thiocarbamoyl-pyrazoline ligands to assess their antimicrobial, mutagenic, and cytotoxic potential. For antimicrobial activity, the broth microdilution method was performed against ATCC strains of Candida spp. and fluconazole dose-dependent isolates of C. glabrata obtained from urine samples. The Ames test was used to assess mutagenic potential. The reduction method of the MTS reagent (3 [4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium) was performed with HeLa, SiHa, and Vero cells to determine cytotoxicity. Both complexes exhibited fungistatic and fungicidal activity for the yeasts used in the study, demonstrating greater potential for C. glabrata ATCC 2001 and the C. glabrata CG66 isolate with a Minimum Inhibitory Concentration MIC from 3.90 to 7.81 µg mL-1 and fungicidal action from 7.81 to 15.62 µg mL-1. The complexes inhibited and degraded biofilms by up to 90% and did not present mutagenic and cytotoxic potential at the concentrations evaluated for MIC. Thus, the complexes examined herein suggest promising alternatives for the development of new antifungal drugs.
Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Cobalto/química , Complejos de Coordinación/química , Pirazoles/química , Tiocarbamatos/química , Animales , Biopelículas/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Chlorocebus aethiops , Complejos de Coordinación/farmacología , Cristalografía por Rayos X , Células HeLa , Humanos , Ligandos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Análisis Espectral/métodos , Células VeroRESUMEN
Aim: To assemble, characterize and assess the antifungal effects of a new fluconazole (FLZ)-carrier nanosystem. Materials & methods: The nanosystem was prepared by loading FLZ on chitosan (CS)-coated iron oxide nanoparticles (IONPs). Antifungal effects were evaluated on planktonic cells (by minimum inhibitory concentration determination) and on biofilms (by quantification of cultivable cells, total biomass, metabolism and extracellular matrix) of Candida albicans and Candida glabrata. Results: Characterization results ratified the formation of a nanosystem (<320 nm) with FLZ successfully embedded. IONPs-CS-FLZ nanosystem reduced minimum inhibitory concentration values and, in general, showed similar antibiofilm effects compared with FLZ alone. Conclusion: IONPs-CS-FLZ nanosystem was more effective than FLZ mainly in inhibiting Candida planktonic cells. This nanocarrier has potential to fight fungal infections.
Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Portadores de Fármacos/química , Fluconazol/química , Fluconazol/farmacología , Nanopartículas/química , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Candida albicans/fisiología , Candida glabrata/efectos de los fármacos , Candida glabrata/fisiología , Quitosano/química , Composición de Medicamentos , Pruebas de Sensibilidad MicrobianaRESUMEN
BACKGROUND: Peri-implant inflammation resulting from the presence of Candida biofilms may compromise the longevity of implant-supported dentures. This study evaluated the inhibitory effect of Brazilian red propolis on mono-species biofilms of C. albicans (ATCC 90028) and co-culture biofilms of C. albicans (ATCC 90028) and C. glabrata (ATCC 2001), developed on titanium surfaces. METHODS: Titanium specimens were pre-conditioned with artificial saliva and submitted to biofilm formation (1 × 106 CFU/mL). After 24 h (under microaerophilic conditions at 37 °C) biofilms were submitted to treatment for 10 min, according to the groups: sterile saline solution (growth control), 0.12% chlorhexidine and 3% red propolis extract. Treatments were performed every 24 h for 3 days and analyses were conducted 96 h after initial adhesion. After that, the metabolic activity (MTT assay) (n = 12/group), cell viability (CFU counts) (n = 12/group) and surface roughness (optical profilometry) (n = 6/group) were evaluated. Data from viability and metabolic activity assays were evaluated by ANOVA and Tukey tests. Surface roughness analysis was determined by Kruskal Wallis e Mann Whitney tests. RESULTS: Regarding the mono-species biofilm, the cell viability and the metabolic activity showed that both chlorhexidine and red propolis had inhibitory effects and reduced the metabolism of biofilms, differing statistically from the growth control (p < 0.05). With regards the co-culture biofilms, chlorhexidine had the highest inhibitory effect (p < 0.05). The metabolic activity was reduced by the exposure to chlorhexidine and to red propolis, different from the growth control group (p < 0.05). The surface roughness (Sa parameter) within the mono-species and the co-culture biofilms statistically differed among groups (p < 0.05). CONCLUSIONS: Brazilian red propolis demonstrated potential antifungal activity against Candida biofilms, suggesting it is a feasible alternative for the treatment of peri-implantitis.
Asunto(s)
Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Própolis/farmacología , Antiinfecciosos Locales/farmacología , Brasil , Clorhexidina/farmacología , Propiedades de Superficie , TitanioRESUMEN
The continuous emergence of Candida strains resistant to currently used antifungals demands the development of new alternatives that could reduce the burden of candidiasis. In this work silver nanoparticles synthesized using a green route are efficiently used, alone or in combination with fluconazole, amphotericin B or nystatine, to inhibit growth of C. albicans and C. glabrata oral clinical strains, including in strains showing resistance to fluconazole. A potent inhibitory effect over biofilm formation prompted by the two Candida species was also observed, including in mature biofilm cells. These results foster the use of phytotherapeutics as effective treatments in oral candidiasis.
Asunto(s)
Antifúngicos/farmacología , Azoles/farmacología , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Nanopartículas del Metal/química , Polienos/farmacología , Granada (Fruta)/química , Anfotericina B/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Fluconazol/farmacología , Pruebas de Sensibilidad Microbiana , Nistatina/farmacología , Plata/farmacologíaRESUMEN
Strategies to enhance corneal penetration of voriconazole (VOR) could improve the treatment of fungal keratitis. Here, we evaluated the use of iontophoresis for ocular VOR delivery from either: (i) a cyclodextrin inclusion complex (CD VOR), (ii) a liposome (LP VOR), and (iii) a chitosan-coated liposome (LP VOR CS). LP VOR CS presented mean diameter of 139.2⯱â¯1.3â¯nm and zeta potential equal toâ¯+â¯3.3⯱â¯1.5â¯mV compared to 134.6⯱â¯1.7 and -8.2⯱â¯3.0â¯mV of LP VOR, which, together with mucin mucoadhesion study, confirmed chitosan-coating. Both drug and liposomal formulations were stable under the influence of an applied electric current. Interestingly, in vitro studies in Candida glabrata culture indicated a decrease in VOR MIC values following iontophoresis (from 0.28 to 0.14⯵g/mL). Iontophoresis enhanced drug penetration into the cornea. After 10â¯min of a 2â¯mA/cm2 applied current, corneal retained amounts were 45.4⯱â¯11.2, 30.4⯱â¯2.1 and 30.6⯱â¯2.9⯵g/cm2 for, respectively, CD VOR, LP VOR, and LP VOR CS. In conclusion, iontophoresis increases drug potency and enhances drug penetration into the cornea, showing potential to be used as "an emergency burst delivery approach".
Asunto(s)
Antifúngicos/administración & dosificación , Candida glabrata/efectos de los fármacos , Córnea/metabolismo , Iontoforesis , Voriconazol/administración & dosificación , Administración Oftálmica , Animales , Antifúngicos/química , Antifúngicos/metabolismo , Candida glabrata/crecimiento & desarrollo , Quitosano/química , Ciclodextrinas/química , Composición de Medicamentos , Lípidos/química , Liposomas , Pruebas de Sensibilidad Microbiana , Nanopartículas , Sus scrofa , Distribución Tisular , Voriconazol/química , Voriconazol/metabolismoRESUMEN
Candidemia has been considered a persistent public health problem with great impact on hospital costs and high mortality. We aimed to evaluate the epidemiology and prognostic factors of candidemia in a tertiary hospital in Northeast Brazil from January 2011 to December 2016. Demographic and clinical data of patients were retrospectively obtained from medical records and antifungal susceptibility profiling was performed using the broth microdilution method. A total of 68 episodes of candidemia were evaluated. We found an average incidence of 2.23 episodes /1000 admissions and a 30-day mortality rate of 55.9%. The most prevalent species were Candida albicans (35.3%), Candida tropicalis (27.4%), Candida parapsilosis (21.6%) and Candida glabrata (11.8%). Higher mortality rates were observed in cases of candidemia due to C. albicans (61.1%) and C. glabrata (100%), especially when compared to C. parapsilosis (27.3%). Univariate analysis revealed some variables which significantly increased the probability of death: older age (P = 0.022; odds ratio [OR] = 1.041), severe sepsis (P < 0.001; OR = 8.571), septic shock (P = 0.035; OR = 3.792), hypotension (P = 0.003; OR = 9.120), neutrophilia (P = 0.046; OR = 3.080), thrombocytopenia (P = 0.002; OR = 6.800), mechanical ventilation (P = 0.009; OR = 8.167) and greater number of surgeries (P = 0.037; OR = 1.920). Multivariate analysis showed that older age (P = 0.040; OR = 1.055), severe sepsis (P = 0.009; OR = 9.872) and hypotension (P = 0.031; OR = 21.042) were independently associated with worse prognosis. There was no resistance to amphotericin B, micafungin or itraconazole and a low rate of resistance to fluconazole (5.1%). However, 20.5% of the Candida isolates were susceptible dose-dependent (SDD) to fluconazole and 7.7% to itraconazole. In conclusion, our results could assist in the adoption of strategies to stratify patients at higher risk for developing candidemia and worse prognosis, in addition to improve antifungal management.
Asunto(s)
Candidemia/diagnóstico , Candidemia/epidemiología , Infección Hospitalaria/diagnóstico , Infección Hospitalaria/epidemiología , Choque Séptico/diagnóstico , Choque Séptico/epidemiología , Adulto , Factores de Edad , Anciano , Análisis de Varianza , Antifúngicos/uso terapéutico , Brasil/epidemiología , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Candida albicans/patogenicidad , Candida glabrata/efectos de los fármacos , Candida glabrata/crecimiento & desarrollo , Candida glabrata/patogenicidad , Candida parapsilosis/efectos de los fármacos , Candida parapsilosis/crecimiento & desarrollo , Candida parapsilosis/patogenicidad , Candida tropicalis/efectos de los fármacos , Candida tropicalis/crecimiento & desarrollo , Candida tropicalis/patogenicidad , Candidemia/tratamiento farmacológico , Candidemia/mortalidad , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/mortalidad , Farmacorresistencia Fúngica , Femenino , Humanos , Hipertensión/diagnóstico , Hipertensión/fisiopatología , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Respiración Artificial/efectos adversos , Respiración Artificial/estadística & datos numéricos , Estudios Retrospectivos , Factores de Riesgo , Choque Séptico/tratamiento farmacológico , Choque Séptico/mortalidad , Análisis de Supervivencia , Centros de Atención Terciaria , Trombocitopenia/diagnóstico , Trombocitopenia/fisiopatologíaRESUMEN
Increasing resistance to current fungicides is a clinical problem that leads to the need for new treatment strategies. Clove oil (CO) has already been described as having antifungal action. However, it should not be applied directly to the skin as it may be irritating. One option for CO delivery and suitable topical application would be nanoemulsions (NEs). NEs have advantages such as decreased irritant effects and lower dose use. The purpose of this work was the development of NEs containing CO and in vitro evaluation against Candida albicans and Candida glabrata. The NEs were produced by an ultrasonic processor with different proportions of CO and Pluronic® F-127. In order to determine the best composition and ultrasound amplitude, an experimental design was performed. For the evaluation, droplet size and polydispersity index (PdI) were used. After the stability study, in vitro activity against C. albicans and C. glabrata was evaluated. NEs selected for the stability study, with diameter <40 nm and PdI <0.2, remained stable for 420 d. Activity against Candida spp. was improved when the CO was nanoemulsified, for it possibly leads to a better interaction between the active and the microorganisms, mainly in C. albicans.
Asunto(s)
Aceite de Clavo/química , Emulsiones/química , Nanoestructuras/química , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Aceite de Clavo/farmacología , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Poloxámero/química , SonicaciónRESUMEN
BACKGROUND: Phytolacca tetramera is an endemic plant from Argentina that is currently at serious risk because its environment is subjected to a high anthropic impact. A previous study has shown that berry extracts obtained from this plant display antifungal activity against multiple human-pathogenic fungi when tested with a non-standardized method. Further evidences of the antifungal properties of other parts of the plant and studies of mechanism of antifungal action of the antifungal chemically characterized extracts are required. PURPOSE: This study aimed to gain further evidence of the antifungal activity of P. tetramera berry, leaf and root extracts in order to find the most active extract to be developed as an Herbal Medicinal Antifungal Product. The medicinal usefulness of P. tetramera extracts as antifungal agents will serve as an important support to create concience and carry out actions tending to the preservation of this threatened species and its environment. MATERIALS AND METHODS: Chemical analysis of all P. tetramera extracts, including quantitation of selected markers, was performed through UHPLC-ESI-MS/MS and UPLC-ESI-MS techniques according to the European Medicines Agency (EMA). The antifungal activity of the quantified extracts was tested with the standardized CLSI microbroth dilution method against Candida spp. Antifungal mechanisms of the most active extract were studied by examination of morphological changes by phase-contrast and fluorescence microscopies and both, cellular and enzymatic assays targeting either the fungal membrane or the cell wall. RESULTS: The antifungal activity of twelve P. tetramera extracts was tested against Candida albicans and Candida glabrata. The dichloromethane extract from berries (PtDEb) showed the best activity. Phytolaccagenin (PhytG) and phytolaccoside B (PhytB) were selected as the main active markers for the antifungal P. tetramera extracts. The quantitation of these active markers in all extracts showed that PtDEb possessed the highest amount of PhytG and PhytB. Finally, studies on the mechanism of antifungal action showed that the most active PtDEb extract produces morphological changes compatible with a damage of the cell wall and/or the plasma membrane. Cellular and enzymatic assays showed that PtDEb would not damage the fungal cell wall by itself, but would alter the plasma membrane. In agreement, PtDEb was found to bind to ergosterol, the main sterol of the fungal plasma membrane. CONCLUSION: Studies of the anti-Candida activity of P. tetramera extracts led to the selection of PtDEb as the most suitable extract, confirming the antifungal properties of the threatened species P. tetramera. The new data give a valuable reason for the definitive protection of this sp. and its natural environment thus allowing further studies for the future development of an Herbal Medicinal Antifungal Product.
Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Ácido Oleanólico/análogos & derivados , Phytolacca/química , Extractos Vegetales/farmacología , Saponinas/farmacología , Antifúngicos/química , Argentina , Ergosterol/metabolismo , Frutas/química , Humanos , Cloruro de Metileno , Ácido Oleanólico/química , Ácido Oleanólico/farmacología , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Plantas Medicinales , Saponinas/química , Espectrometría de Masas en TándemRESUMEN
OBJECTIVE: The objective of this study was to describe the prevalence, microbiological profile, bacterial resistance, and the sensitivity to antibiotics of microorganisms causing urinary tract infection (UTI) at a single-site tertiary referral hospital in the western region of Mexico. METHODS: A total of 5895 culture samples processed at the microbiology laboratory from August 1, 2014, to July 31, 2015, were analyzed. RESULTS: A total of 5895 samples for urine cultures (UC) were collected, of which 3363 were taken in women (57.05%) and 2532 in men (42.95%). A prevalence of 24% was calculated. From 1444 positive UC, 1512 microorganisms were isolated; the major etiological agent was Escherichia coli, representing 67.28% followed by Pseudomonas with 7.12%. With respect to fungi, Candida glabrata was found as the most common agent. Susceptibility to daptomycin and linezolid was 100%, and meropenem, 91.4%. Highest antimicrobial resistance was found for ampicillin (77.47%) and moxifloxacin (72.89%). Nearly 49% of E. coli strains and 27% of Klebsiella pneumoniae strains showed extended-spectrum beta-lactamase (ESBL) production. CONCLUSIONS: Bacterial UTI persists as one of the most common infections affecting all age groups and both genders. As in other countries, E. coli ranks first in Mexico, with 67.28%, and nearly 50% of the strains produce ESBL.
OBJETIVO: Describir la prevalencia, el perfil microbiológico, la resistencia y la sensibilidad a los antibióticos de microorganismos causantes de infecciones de vías urinarias en un centro de referencia de tercer nivel en el occidente de México. MÉTODO: Se realizó un estudio transversal que incluyó 5895 urocultivos procesados en el laboratorio de microbiología del 1 de agosto de 2014 al 31 de julio de 2015. RESULTADOS: De los 5895 urocultivos, 3363 correspondieron a mujeres (57.05%) y 2532 a varones (42.95%). De los 1444 resultados positivos, se aislaron 1512 microorganismos (prevalencia del 24%); el más común fue Escherichia coli, con un 67.28%, seguido por Pseudomonas con un 7.12%. Candida glabrata se reportó como el patógeno fúngico más frecuente. De manera general, la sensibilidad a la daptomicina y al linezolid fue del 100%, y al meropenem fue del 91.4%. La resistencia más alta se reportó para ampicilina y moxifloxacino (77.47 y 72.89%, respetivamente). Cerca del 49% y del 27% de las cepas de E. coli y Klebsiella pneumoniae mostraron producción de betalactamasas de espectro extendido. CONCLUSIONES: Las infecciones de vías urinarias persisten como una de las formas más habituales de infección y afectan a todos los grupos de edad. En México, al igual que en otros países, E. coli se coloca en primer lugar de frecuencia, con el 67.28%.
Asunto(s)
Farmacorresistencia Microbiana , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Candida glabrata/efectos de los fármacos , Candida glabrata/aislamiento & purificación , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Estudios Transversales , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/microbiología , Masculino , México , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pseudomonas/efectos de los fármacos , Pseudomonas/aislamiento & purificación , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Centros de Atención Terciaria , Adulto JovenRESUMEN
Fungal resistance is the major problem related to fluconazole treatments. This study aims to develop innovative lipid core nanocapsules and nanostructured lipid carriers containing fluconazole, to study in vitro antifungal activity and to assess the possibility of resistance reversion in Candida albicans, C. glabrata, C. krusei, and C. tropicalis isolates. The action mechanism of nanoparticles was investigated through efflux pumps and scanning electron microscopy studies. The lipid core nanocapsules and nanostructured lipid carriers were prepared by interfacial deposition of preformed polymer and high-pressure homogenization methods, respectively. Both nanostructures presented sizes below 250 nm, SPAN < 1.6, negative zeta potential, pH slightly acid, high drug content and controlled drug release. The nanostructured lipid carriers were unable to reverse the fungal resistance. Lipid core nanoparticles displayed advantages such as a reduction in the effective dose of fluconazole and resistance reversion in all isolates tested - with multiple mechanisms of resistance. The main role of the supramolecular structure and the composition of the nanoparticles on antifungal mechanisms of action were discussed. The results achieved through this study have an impact on clinical therapy, with a potential application in the treatment of fungal infections caused by resistant isolates of Candida spp.
Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Preparaciones de Acción Retardada/química , Farmacorresistencia Fúngica/efectos de los fármacos , Fluconazol/farmacología , Proteínas Fúngicas/antagonistas & inhibidores , Nanopartículas/química , Transportadoras de Casetes de Unión a ATP/antagonistas & inhibidores , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Candida/genética , Candida/crecimiento & desarrollo , Candida/metabolismo , Candida albicans/efectos de los fármacos , Candida albicans/genética , Candida albicans/crecimiento & desarrollo , Candida albicans/metabolismo , Candida glabrata/efectos de los fármacos , Candida glabrata/genética , Candida glabrata/crecimiento & desarrollo , Candida glabrata/metabolismo , Candida tropicalis/efectos de los fármacos , Candida tropicalis/genética , Candida tropicalis/crecimiento & desarrollo , Candida tropicalis/metabolismo , Caprilatos/química , Composición de Medicamentos/métodos , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Genes MDR/efectos de los fármacos , Hexosas/química , Concentración de Iones de Hidrógeno , Pruebas de Sensibilidad Microbiana , Nanopartículas/ultraestructura , Palmitatos/química , Tamaño de la Partícula , Triglicéridos/química , Verapamilo/farmacologíaRESUMEN
BACKGROUND: Photosensitizers in nanocarriers have been investigated for antimicrobial Photodynamic Therapy (aPDT). However, most studies are focused against microorganisms in planktonic or monospecies biofilm. Thus, this in vitro study evaluated the effect of aPDT using Chloroaluminium phthalocyanine (ClAlPc) in cationic nanoemulsion (NE) against Candida albicans, Candida glabrata and Streptococcus mutans grown as multispecies biofilm. METHODS: Standard suspensions of each microorganism were added into wells of a microtiter plate for biofilm growth for 48 h in a candle jar. The biofilms were incubated with ClAlPc in cationic NE at 31.8 µM for 30 min and illuminated with red light fluence of 39.3 J/cm2 (P+L+ group). Additional samples were treated only with photosensitizer (P+L-) or red light (P-L+) or neither (P-L-, control group). aPDT efficacy was assessed by colony quantification, biofilm's metabolic activity, total biomass, and confocal microscopy. Data were analyzed by ANOVA/Welch and post-hoc Tukey/Games-Howell tests (α = 0.05). RESULTS: aPDT (P+L+) reduced the colony count in 1.30 to 2.24 lg10 and the metabolic activity in 53.7% compared with the control group (P-L-). The total biomass showed no statistical difference among the groups. The confocal microscopy analyzes showed uptake of the PS in the biofilm, and dead cells were observed in the biofilm treated with aPDT. CONCLUSION: aPDT mediated by ClAlPc in cationic NE promoted photoinactivation of the multispecies biofilm, which was confirmed by colony quantification, metabolic activity, and confocal microscopy. However, the total biomass of the biofilm was not affected by the treatment.