RESUMEN

Microorganisms can induce diseases with significant clinical implications for human health. Multidrug-resistant microorganisms have been on the rise worldwide over the past few decades, and no new antibiotics have been introduced to the market in a considerable amount of time. Such situation highlights the urgency of discovering new antimicrobial drugs to address this pressing issue. Therefore, the objective of this study was to identify bioactive compounds against 15 species of bacteria and 5 species of fungi of clinical relevance through in vitro screening of 58 synthetic compounds from four chemical classes of our internal library of synthetic compounds. Our findings highlight arylpiperazines 18, 20, 26, 27, and 29, and the aminothiazole 50, as potent broad-spectrum antimicrobials (MICs = 12.5 - 15.6 mg.mL-1) against clinically relevant bacteria and fungi. Additionally, these compounds displayed low cytotoxicity against various host cells and a favorable in vitro pharmacokinetic profile for oral administration. Indeed, all six showed adequate lipophilicity, high gastrointestinal permeability, metabolic stability in human and mouse liver microsomes, and satisfactory aqueous solubility. Thus, they emerge as promising starting points for hit-to-lead studies towards new antibacterial and antifungal agents, especially against Staphylococcus epidermidis, Staphylococcus aureus, Lactobacillus paracasei and Candida orthopsilosis.

RESUMEN

Introduction: Despite the rising concern with fungal resistance, a myriad of molecules has yet to be explored. Geraniol, linalool, and citronellal are monoterpenes with the same molecular formula (C10H18O), however, neither the effect of these compounds on inflammatory axis induced by Candida spp. nor the antibiofilm Structure-Activity Relationship (SAR) have been well-investigated. Herein we analyzed geraniol, linalool and citronellal antifungal activity, cytotoxicity, and distinctive antibiofilm SAR, also the influence of geraniol on Candida spp induced dysregulated inflammatory axis, and in vivo toxicity. Methods: Minimal inhibitory (MIC) and fungicidal (MFC) concentrations against Candida spp were defined, followed by antibiofilm activity (CFU-colony forming unit/mL/g of dry weight). Cytotoxic activity was assessed using human monocytes (THP-1) and oral squamous cell (TR146). Geraniol was selected for further analysis based on antifungal, antibiofilm and cytotoxic results. Geraniol was tested using a dual-chamber co-culture model with TR146 cells infected with C. albicans, and THP-1 cells, used to mimic oral epithelium upon fungal infection. Expression of Candida enzymes (phospholipase-PLB and aspartyl proteases-SAP) and host inflammatory cytokines (interleukins: IL-1ß, IL-6, IL-17, IL-18, IL-10, and Tumor necrosis factor-TNF) were analyzed. Lastly, geraniol in vivo toxicity was assessed using Galleria mellonella. Results: MIC values obtained were 1.25-5 mM/mL for geraniol, 25-100 mM/mL for linalool, and 100-200 mM/mL for citronellal. Geraniol 5 and 50 mM/mL reduced yeast viability during biofilm analysis, only 500 mM/mL of linalool was effective against a 72 h biofilm and no biofilm activity was seen for citronellal. LD50 for TR146 and THP-1 were, respectively: geraniol 5.883 and 8.027 mM/mL; linalool 1.432 and 1.709 mM/mL; and citronellal 0.3006 and 0.1825 mM/mL. Geraniol was able to downregulate expression of fungal enzymes and host pro-inflammatory cytokines IL-1ß, IL-6, and IL-18. Finally, safety in vivo parameters were observed up to 20 mM/Kg. Discussion: Despite chemical similarities, geraniol presented better antifungal, antibiofilm activity, and lower cytotoxicity when compared to the other monoterpenes. It also showed low in vivo toxicity and capacity to downregulate the expression of fungal enzymes and host pro-inflammatory cytokines. Thus, it can be highlighted as a viable option for oral candidiasis treatment.

RESUMEN

Chalcone (E)-1,3-diphenyl-prop-2-en-1-one and a series of 14 methoxylated derivatives have been synthesized via Claisen-Schmidt aldol condensation and characterized by FTIR, CG/MS/DIC, 1D (1H and 13C), 2D (COSY, HSQC, and HMBC) NMR, and EMAR techniques. All molecules were tested at 1 mM concentration for antifungal (Sclerotium sp., Macrophomina phaesolina and Colletotrichum gloeosporioides), antibacterial (Acidovorax citrulli two strains), and antiprotozoal (Phytomonas serpens) activities. Unmodified chalcone (CH0) and derivatives CH1, CH2, CH8 stood out in terms of antifungal activity. CH0 presented IC50 values of 47.3 µM (9.8 µg/mL) for the fungus C. gloeosporioides. In addition, fluorescence microscopy indicated that CH0 promoted loss of hyphal cell membrane integrity. The CH1 and CH2 derivatives promoted the inhibition of Sclerotium sp. with IC50 of 127.5 µM (32.9 µg/mL) and 110.4 µM (29.6 µg/mL), respectively. All molecules showed high activity against the phytoparasite P. serpens with IC50 values of 0.98, 2.40, 10.25, and 3.11 µM for the derivatives CH2, CH3, CH5 and CH14 respectively. The results demonstrated that derivatives methoxylated in both rings (CH2) as well as derivatives with a furan ring associated with the methoxy group in ring A, as well as unmodified chalcone can be promising agricultural fungicides for controlling the fungi studied.

RESUMEN

BACKGROUND: Invasive fungal diseases (IFD) are high morbidity and mortality infections in children with cancer suffering episodes of high-risk febrile neutropenia (HRFN). IFD epidemiology has changed in the last two decades, with an increasing incidence in recent years due to the growing number of immunocompromised children at risk for IFD. The aim of this study was to evaluate the incidence of IFD in children with cancer in the period 2016-2020 compared to 2004-2006 in six hospitals in Chile. METHODS: Prospective, multicentre study, carried out between 2016 and 2020 in six hospitals in Chile. The defined cohort corresponds to a dynamic group of HRFN episodes in patients <18 years old with cancer, who at the fourth day of evolution still presented fever and neutropenia (persistent HRFN). Each episode was followed until resolution of FN. The incidence of IFD was calculated between 2016 and 2020 and compared with data obtained in the period 2004-2006. The incidence rate was estimated. RESULTS: A total of 777 episodes of HRFN were analysed; 257 (33.1%) were considered as persistent-HRFN occurring in 174 patients. The median age was 7 years (IQR: 3-12 years) and 52.3% (N = 91) were male. Fifty-three episodes of IFD were detected: 21 proven, 14 probable and 18 possible. Possible IFD were excluded, leaving 239 episodes of persistent-HRFN with an IFD incidence of 14.6% (95% CI 10.5-19.9) and an incidence rate of 13.6 IFD cases per 1000 days of neutropenia (95% CI 9.5-20.0). Compared to 2004-2006 cohort (incidence: 8.5% (95% CI 5.2-13.5)), a significant increase in incidence of 6.1% (95% CI 0.2-12.1, p = .047) was detected in cohorts between 2016 and 2020. CONCLUSION: We observed a significant increase in IFD in 2016-2020, compared to 2004-2006 period.

Asunto(s)

Infecciones Fúngicas Invasoras , Neoplasias , Humanos , Chile/epidemiología , Masculino , Estudios Prospectivos , Niño , Femenino , Preescolar , Infecciones Fúngicas Invasoras/epidemiología , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Neoplasias/epidemiología , Neoplasias/complicaciones , Incidencia , Huésped Inmunocomprometido , Adolescente , Lactante , Antineoplásicos/uso terapéutico

RESUMEN

BACKGROUND: The aim of this study was to summarize existing data and perform technological prospecting on the effect of incorporating antifungal agents into denture base materials in inhibiting Candida spp., as well as to explore the antimicrobial properties of these materials. METHODS: A comprehensive electronic search was carried out in six major bibliographic databases (PubMed, Scopus, Embase, Cochrane Library, Web of Science and Lilacs) until February 2024. In addition, international patent databases were also examined. The search process, study and patent selection, data extraction and risk of bias assessment were carried out independently by researchers. The collected data underwent qualitative analysis. RESULTS: A total of 10 718 articles were identified in the searched databases, of which 40 documents were included for qualitative data analysis (articles: 31; patents: 9). The majority of the studies focused on investigating tissue conditioners (n = 14) and acrylic resins (n = 14). The primary antifungal agents studied were nystatin (n = 15) and fluconazole (n = 13). The most commonly utilized microbiological evaluation methodology was the agar diffusion test (n = 16), followed by the microdilution (n = 7) and biofilm formation assays (n = 7). All of the studies investigated the inhibitory effect of these materials against Candida species. CONCLUSION: The incorporation of antifungal agents into denture base materials has been extensively studied and has shown a significant inhibitory response against Candida spp. across various methodological assays.

RESUMEN

The emergence of fungal pathogens and changes in the epidemiological landscape are prevalent issues in clinical mycology. Reports of resistance to antifungals have been reported. This review aims to evaluate molecular and nonmolecular mechanisms related to antifungal resistance. Mutations in the ERG genes and overexpression of the efflux pump (MDR1, CDR1 and CDR2 genes) were the most reported molecular mechanisms of resistance in clinical isolates, mainly related to Azoles. For echinocandins, a molecular mechanism described was mutation in the FSK genes. Furthermore, nonmolecular virulence factors contributed to therapeutic failure, such as biofilm formation and selective pressure due to previous exposure to antifungals. Thus, there are many public health challenges in treating fungal infections.

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[Box: see text].

Asunto(s)

Antifúngicos , Farmacorresistencia Fúngica , Hongos , Micosis , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Farmacorresistencia Fúngica/genética , Humanos , Micosis/microbiología , Micosis/tratamiento farmacológico , Micosis/epidemiología , Hongos/efectos de los fármacos , Hongos/genética , Hongos/patogenicidad , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Mutación , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Azoles/farmacología , Azoles/uso terapéutico , Pruebas de Sensibilidad Microbiana , Factores de Virulencia/genética , Equinocandinas/farmacología , Equinocandinas/uso terapéutico

RESUMEN

Antimicrobial peptides (AMPs) are important mediator molecules of the innate defense mechanisms in a wide range of living organisms, including bacteria, mammals, and plants. Among them, peptide protease inhibitors (PPIs) from plants play a central role in their defense mechanisms by directly attacking pathogens or by modulating the plant's defense response. The growing prevalence of microbial resistance to currently available antibiotics has intensified the interest concerning these molecules as novel antimicrobial agents. In this scenario, PPIs isolated from a variety of plants have shown potential in inhibiting the growth of pathogenic bacteria, protozoans, and fungal strains, either by interfering with essential biochemical or physiological processes or by altering the permeability of biological membranes of invading organisms. Moreover, these molecules are active inhibitors of a range of proteases, including aspartic, serine, and cysteine types, with some showing particular efficacy as trypsin and chymotrypsin inhibitors. In this review, we provide a comprehensive analysis of the potential of plant-derived PPIs as novel antimicrobial molecules, highlighting their broad-spectrum antimicrobial efficacy, specificity, and minimal toxicity. These natural compounds exhibit diverse mechanisms of action and often multifunctionality, positioning them as promising molecular scaffolds for developing new therapeutic antibacterial agents.

RESUMEN

Fungal infections represent a serious health problem worldwide. The study evaluated the antifungal activity of 4-chlorobenzyl p-coumarate, an unprecedented semi-synthetic molecule. Docking molecular and assay experiments were conducted to determine the Minimum Inhibitory Concentration (MIC) and Minimum Fungicidal Concentration (MFC), mode of action, effect on growth, fungal death kinetics, drug association, effects on biofilm, micromorphology, and against human keratinocytes. The investigation included 16 strains of Candida spp, including C. albicans, C. krusei, C. glabrata, C. tropicalis, C. dubliniensis, C. lusitaniae, C. utilis, C. rugosa, C. guilhermondi, and C. parapsilosis. Docking analysis predicted affinity between the molecule and all tested targets. MIC and MFC values ranged from 3.9 µg/mL (13.54 µM) to 62.5 µg/mL (217.01 µM), indicating a probable effect on the plasma membrane. The molecule inhibited growth from the first hour of testing. Association with nystatin proved to be indifferent. All concentrations of the molecule reduced fungal biofilm. The compound altered fungal micromorphology. The tested compound exhibited an IC50 of 7.90±0.40 µg/mL (27.45±1.42 µM) for keratinocytes. 4-chlorobenzyl p-coumarate showed strong fungicidal effects, likely through its action on the plasma membrane and alteration of fungal micromorphology, and mildly cytotoxic to human keratinocytes.

Asunto(s)

Antifúngicos , Biopelículas , Candida , Pruebas de Sensibilidad Microbiana , Antifúngicos/farmacología , Antifúngicos/química , Antifúngicos/síntesis química , Humanos , Biopelículas/efectos de los fármacos , Candida/efectos de los fármacos , Relación Estructura-Actividad , Simulación del Acoplamiento Molecular , Queratinocitos/efectos de los fármacos , Estructura Molecular , Relación Dosis-Respuesta a Droga , Ácidos Cumáricos/farmacología , Ácidos Cumáricos/química , Ácidos Cumáricos/síntesis química , Supervivencia Celular/efectos de los fármacos

RESUMEN

Among microorganisms found in food, fungi stand out because they are adaptable and competitive in a large range of water activities, temperatures, pHs, humidities and substrate types. Besides sporulating, some species are toxigenic and produce toxic metabolites, mycotoxins, under adverse biotic and abiotic variables. Microorganisms are inactivated along the food chain, but mycotoxins have stable structures and remain in ready-to-eat food. The most prevalent mycotoxins in food, which are aflatoxins, fumonisins, ochratoxin A, patulin, tenuazonic acid, trichothecenes and zearalenone, have maximum tolerable limits (MTLs) defined as ppb and ppt by official organizations. The chronic and acute toxicities of mycotoxins and their stability are different in a chemical family. This critical review aims to discuss promising scientific research that successfully mitigated levels of mycotoxins and focus the results of our research group on this issue. It highlights the application of natural antifungal compounds, combinations of management, processing parameters and emergent technologies, and their role in reducing the levels and bioaccessibility. Despite good crop management and processing practices, total decontamination is almost impossible. Experimental evidence has shown that exposure to mycotoxins may be mitigated. However, multidisciplinary efforts need to be made to improve the applicability of successful techniques in the food supply chain to avoid mycotoxins' impact on global food insecurity.

RESUMEN

INTRODUCTION: A specialized service for antifungal blood level determination is not available in Colombia. This service is essential for the proper follow-up of antifungal therapies. OBJECTIVE: To standardize and validate a simple, sensitive, and specific protocol based on high-performance liquid chromatography with a diode array detector for voriconazole blood level quantification. MATERIALS AND METHODS: We used an Agilent HPLC™ series-1200 equipment with a UVdiode array detector with an analytical column Eclipse XDB-C18 and pre-column Eclipse- XDB-C18 (Agilent). We used voriconazole as the primary control and posaconazole as an internal control. We performed the validation following the Food and Drug Administration (FDA) recommendations. RESULTS: The best chromatographic conditions were: Column temperature of 25°C, UV variable wavelength detection at 256 nm for voriconazole and 261 nm for posaconazole (internal standard); 50 µl of injection volume, 0,8 ml/min volume flow, 10 minutes of run time, and mobile phase of acetonitrile:water (60:40). Finally, retention times were 3.13 for voriconazole and 5.16 minutes for posaconazole. Quantification range varied from 0.125 µg/ml to 16 µg/ml. CONCLUSION: The selectivity and chromatographic purity of the obtained signal, the detection limits, and the standardized quantification make this method an excellent tool for the therapeutic monitoring of patients treated with voriconazole.

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Introducción. Hasta la fecha, Colombia no cuenta con un servicio especializado de medición de niveles séricos de antifúngicos, procedimiento esencial para el adecuado seguimiento del tratamiento de infecciones fúngicas invasoras. Objetivo. Estandarizar y validar un protocolo ­simple, sensible y específico­ basado en la aplicación de cromatografía líquida de alta eficiencia acoplada con un detector de arreglo de diodos para la cuantificación de los niveles séricos de voriconazol. Materiales y métodos. Se usó un equipo HPLC-Agilent™, serie-1200, con un detector UVDAD, una columna analítica Eclipse-XDB-C18 y una pre-columna Eclipse-XDB-C18, ambas de la marca Agilent. Como control primario se utilizó voriconazol y como control interno, posaconazol. La validación se hizo cumpliendo todos los criterios de aceptación recomendados por la Food and Drug Administration (FDA). Resultados. Las mejores condiciones cromatográficas se obtuvieron con los siguientes parámetros: temperatura de la columna de 25 °C, detección UV-VWD de 261 nm, volumen de inyección de 50 µl, flujo de 0,8 ml/minuto y un tiempo de corrido de 10 minutos. La fase móvil usada fue acetonitrilo:agua (60:40) y los tiempos finales de retención fueron de 3,13 para voriconazol y de 5,16 minutos para posaconazol. El rango de cuantificación fue desde 0,125 µg/ml hasta 16 µg/ml. Conclusiones. La selectividad y la pureza de la señal cromatográfica, así como los límites de detección y cuantificación estandarizados hacen de esta metodología una excelente herramienta para el seguimiento terapéutico de pacientes tratados con voriconazol o en profilaxis con este fármaco.

Asunto(s)

Antifúngicos , Triazoles , Voriconazol , Voriconazol/sangre , Cromatografía Líquida de Alta Presión/métodos , Antifúngicos/sangre , Humanos , Triazoles/sangre , Triazoles/análisis , Reproducibilidad de los Resultados , Monitoreo de Drogas/métodos , Monitoreo de Drogas/instrumentación , Monitoreo de Drogas/normas , Límite de Detección

RESUMEN

Oral infections occur due to contact between biofilm rich in Candida albicans formed on the inner surface of complete dentures and the mucosa. This study investigated historical advances in the prevention and treatment of oral mucosal infection and identified gaps in the literature. Bibliographic research was conducted, looking at PubMed, Embase, Web of Science, and Scopus, where 935 articles were found. After removing duplicates and excluding articles by reading the title and abstract, 131 articles were selected for full reading and 104 articles were included. Another 38 articles were added from the gray literature. This review followed the PRISMA-ScR guidelines. The historical period described ranges from 1969 to 2023, in which, during the 21st century, in vitro and in vivo studies became more common and, from 2010 to 2023, the number of randomized controlled trials increased. Among the various approaches tested are the incorporation of antimicrobial products into prosthetic materials, the improvement of oral and denture hygiene protocols, the development of synthetic and natural products for the chemical control of microorganisms, and intervention with local or systemic antimicrobial agents. Studies report good results with brushing combined with sodium hypochlorite, and new disinfectant solutions and products incorporated into prosthetic materials are promising.

RESUMEN

OBJECTIVES: This systematic review and meta-analysis aimed to evaluate the clinical and mycological effectiveness of mucoadhesives as vehicles for drugs or natural products in the treatment of oral candidiasis. MATERIALS AND METHODS: The search for articles was carried out in the Medline/PubMed, SCOPUS, EMBASE, Web of Science, Cochrane Library, and SciELO databases before August 2023. We selected the studies, extracted the data, evaluated the study quality, graded the evidence, performed the risk of bias, and carried out meta-analysis. RESULTS: A total of 389 potentially relevant articles were identified, and 11 studies (1869 participants) met the inclusion criteria of the systematic review. The overall risk of bias was considered low. The most common presentation of mucoadhesives was tablets, with miconazole being the most frequently drug used in the delivery system. Mucoadhesives demonstrated comparable efficacy with topical or systemic antifungal agents, with no significant differences between treatments in terms of clinical (RR = 0.907; 95CI = 0.3-1.297; p = 0.591; I2 = 64.648) or mycological (RR = 0.95; 95CI = 0.667-1.360; p = 0.789; I2 = 73.271) efficacy. CONCLUSIONS: Mucoadhesives may be a suitable alternative to conventional treatments, with the advantage of reducing the frequency of application by up to 5 times and the daily dosage by up to 20 times.

Asunto(s)

Antifúngicos , Candidiasis Bucal , Sistemas de Liberación de Medicamentos , Candidiasis Bucal/tratamiento farmacológico , Humanos , Antifúngicos/administración & dosificación , Antifúngicos/uso terapéutico , Miconazol/administración & dosificación , Miconazol/uso terapéutico , Adhesivos , Comprimidos , Mucosa Bucal/microbiología

RESUMEN

Chromoblastomycosis is a fungal chronic disease, which affects humans, especially in cutaneous and subcutaneous tissues. There is no standard treatment for Chromoblastomycosis, and it is a therapeutic challenge, due natural resistance of their causative agents, inadequate response of patients and common cases of relapse. Protocols for determination of antifungal drugs susceptibility are not standardized for chromoblastomycosis agents and endpoint definition is usually based on visual inspection, which depends on the analyst, making it sometimes inaccurate. We presented a colorimetric and quantitative methodology based on resazurin reduction to resofurin to determine the metabolic status of viable cells of Fonsecaea sp. Performing antifungal susceptibility assay by a modified EUCAST protocol allied to resazurin, we validated the method to identify the minimum inhibitory concentrations of itraconazole, fluconazole, amphotericin B, and terbinafine for eight Fonsecaea clinical isolates. According to our data, resazurin is a good indicator of metabolic status of viable cells, including those exposed to antifungal drugs. This work aimed to test resazurin as an indicator of the metabolic activity of Fonsecaea species in susceptibility assays to antifungal drugs. Species of this genus are the main causative agents of Chromoblastomycosis, which affects humans.

Asunto(s)

Antifúngicos , Cromoblastomicosis , Fonsecaea , Pruebas de Sensibilidad Microbiana , Oxazinas , Xantenos , Xantenos/metabolismo , Oxazinas/metabolismo , Antifúngicos/farmacología , Humanos , Fonsecaea/efectos de los fármacos , Fonsecaea/genética , Fonsecaea/metabolismo , Cromoblastomicosis/microbiología , Cromoblastomicosis/tratamiento farmacológico , Colorimetría/métodos

RESUMEN

Antimicrobial peptides (AMP) represent an alternative in the treatment of fungal infections associated with countless deaths. Here, we report a new AMP, named KWI-19, which was designed based on a peptide encrypted in the sequence of an Inga laurina Kunitz-type inhibitor (ILTI). KWI-19 inhibited the growth of Candida species and acted as a fungicidal agent from 2.5 to 20 µmol L-1, also showing synergistic activity with amphotericin B. Kinetic assays showed that KWI-19 killed Candida tropicalis cells within 60 min. We also report the membrane-associated mechanisms of action of KWI-19 and its interaction with ergosterol. KWI-19 was also characterized as a potent antibiofilm peptide, with activity against C. tropicalis. Finally, non-toxicity was reported against Galleria mellonella larvae, thus strengthening the interest in all the bioactivities mentioned above. This study extends our knowledge on how AMPs can be engineered from peptides encrypted in larger proteins and their potential as candicidal agents.

Asunto(s)

Antifúngicos , Candida , Animales , Antifúngicos/farmacología , Anfotericina B/farmacología , Péptidos/farmacología , Candida tropicalis , Inhibidores de Proteasas , Péptido Hidrolasas

RESUMEN

Sporothrix brasiliensis is an emerging zoonotic fungal pathogen that can be difficult to treat. Antifungal susceptibility testing was performed on the mold phase of a convenience sample of 61 Sporothrix spp. isolates from human and cat sporotrichosis cases in Brazil using the Clinical and Laboratory Standards Institute standard M38. A bimodal distribution of azole susceptibility was observed with 50% (28/56) of S. brasiliensis isolates showing elevated itraconazole minimum inhibitory concentrations ≥16 µg/mL. Phylogenetic analysis found the in vitro resistant isolates were not clonal and were distributed across three different S. brasiliensis clades. Single nucleotide polymorphism (SNP) analysis was performed to identify potential mechanisms of in vitro resistance. Two of the 28 resistant isolates (MIC ≥16 mg/L) had a polymorphism in the cytochrome P450 gene, cyp51, corresponding to the well-known G448S substitution inducing azole resistance in Aspergillus fumigatus. SNPs corresponding to other known mechanisms of azole resistance were not identified in the remaining 26 in vitro resistant isolates.

Asunto(s)

Sporothrix , Esporotricosis , Humanos , Antifúngicos/farmacología , Azoles/farmacología , Brasil , Filogenia , Itraconazol/farmacología , Esporotricosis/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Farmacorresistencia Fúngica/genética

RESUMEN

Objetivo: Analisar a expressão fenotípica de fatores de virulência em biofilmes de Candida albicans frente a extratos glicólicos de plantas. Material e Métodos: Os biofilmes de Candida albicans (ATCC 18804) obtidos a partir de incubação de 48 horas foram expostos por 5 minutos e 24 horas a diferentes concentrações de extratos glicólicos de Hamamelis virginiana e Persea americana, Cynara scolymus L e Stryphnodendron barbatiman M, a fim de verificar a ação antifúngica da proteinase, fosfolipase e hemolisina. Resultados: Todos os extratos foram eficazes na redução do biofilme. Em contato por 5 minutos. os extratos reduziram 50% do biofilme. Após 24 horas. o extrato de Persea americana apresentou o biofilme em 90%, seguido de Cynara scolymus, que o interrompeu em 85%. Houve mudança na intensidade da proteinase após 5 minutos e 24 horas, com uma atividade enzimática média de 0,69 em comparação com o controle de 0,49. Cynara scolymus foi o extrato com maior concentração média de 100 mg/ml; a intensidade da fosfolipase foi alterada com Stryphnodendron barbatiman sendo mais efetivo em 24 horas em relação ao controle (p< 0,0001). A secreção de hemolisina foi modificada por Hamamelis virginiana (12,5 mg/ml) após 5 minutos de exposição e em 24 horas. todos os extratos foram capazes de causar alterações na secreção. Conclusão: Os extratos testados apresentam potencial antifúngico em biofilmes de Candida albicans, implicando em redução significativa dos fatores de virulência. Assim, estes podem ser indicados como uma ferramenta terapêutica alternativa para reduzir a morbidade dessas infecções, já que em ambos os tempos de exposição investigados, eles foram capazes de reduzir a secreção enzimática do fungo (AU)

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Objective: Analyze the phenotypic expression of virulence factors in Candida albicans biofilms against plant glycolicextracts. Material and Methods: The biofilms of Candida albicans (ATCC 18804) obtained from incubation for 48 hours were exposed for 5 minutes and 24 hours to different concentrations of glycolic extracts of Hamamelis virginiana and Persea americana, Cynara scolymus L and Stryphnodendron barbatiman M, in order to verify the antifungal activity of the proteinase, phospholipase and hemolysin. Results: All extracts were effective in reducing biofilm. In contact for 5 minutes. the extracts reduced 50% of the biofilm. After 24 hours, the Persea americanaextract showed the biofilm at 90%, followed by Cynara scolymus, which interrupted it at 85%, There was a change in proteinase intensity after 5 minutes and 24 hours. with an average enzymatic activity of 0.69 compared to the control of 0.49. Cynara scolymus was the extract with the highest mean concentration of 100 mg/ml; the phospholipase intensity was changed with Stryphnodendron barbatiman being more effective in 24 hours compared to the control (p< 0.0001). The hemolysin secretion was modified by Hamamelis virginiana (12.5 mg/ml) after 5 minutes of exposure, and in 24 hours. all extracts were capable to cause changes in secretion. Conclusion: The tested extracts have antifungal potential in Candida albicans biofilms, implying a significant reduction in virulence factors. Thus, these can be indicated as an alternative therapeutic tool to reduce the morbidity of these infections, as in both investigated exposure times. they were able to reduce theenzymatic secretion of the fungus (AU)

Asunto(s)

Candida albicans , Extractos Vegetales , Factores de Virulencia , Infecciones , Antifúngicos

RESUMEN

Introduction. A specialized service for antifungal blood level determination is not available in Colombia. This service is essential for the proper follow-up of antifungal therapies. Objective. To standardize and validate a simple, sensitive, and specific protocol based on high-performance liquid chromatography with a diode array detector for voriconazole blood level quantification. Materials and methods. We used an Agilent HPLC™ series-1200 equipment with a UV- diode array detector with an analytical column Eclipse XDB-C18 and pre-column Eclipse-XDB-C18 (Agilent). We used voriconazole as the primary control and posaconazole as an internal control. We performed the validation following the Food and Drug Administration (FDA) recommendations. Results. The best chromatographic conditions were: Column temperature of 25°C, UV variable wavelength detection at 256 nm for voriconazole and 261 nm for posaconazole (internal standard); 50 µl of injection volume, 0,8 ml/min volume flow, 10 minutes of run time, and mobile phase of acetonitrile:water (60:40). Finally, retention times were 3.13 for voriconazole and 5.16 minutes for posaconazole. Quantification range varied from 0.125 µg/ml to 16 µg/ml. Conclusion. The selectivity and chromatographic purity of the obtained signal, the detection limits, and the standardized quantification make this method an excellent tool for the therapeutic monitoring of patients treated with voriconazole.

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Introducción. Hasta la fecha, Colombia no cuenta con un servicio especializado de medición de niveles séricos de antifúngicos, procedimiento esencial para el adecuado seguimiento del tratamiento de infecciones fúngicas invasoras. Objetivo. Estandarizar y validar un protocolo ­simple, sensible y específico­ basado en la aplicación de cromatografía líquida de alta eficiencia acoplada con un detector de arreglo de diodos para la cuantificación de los niveles séricos de voriconazol. Materiales y métodos. Se usó un equipo HPLC-Agilent™, serie-1200, con un detector UVDAD, una columna analítica Eclipse-XDB-C18 y una pre-columna Eclipse-XDB-C18, ambas de la marca Agilent. Como control primario se utilizó voriconazol y como control interno, posaconazol. La validación se hizo cumpliendo todos los criterios de aceptación recomendados por la Food and Drug Administration (FDA). Resultados. Las mejores condiciones cromatográficas se obtuvieron con los siguientes parámetros: temperatura de la columna de 25 °C, detección UV-VWD de 261 nm, volumen de inyección de 50 µl, flujo de 0,8 ml/minuto y un tiempo de corrido de 10 minutos. La fase móvil usada fue acetonitrilo:agua (60:40) y los tiempos finales de retención fueron de 3,13 para voriconazol y de 5,16 minutos para posaconazol. El rango de cuantificación fue desde 0,125 µg/ml hasta 16 µg/ml. Conclusiones. La selectividad y la pureza de la señal cromatográfica, así como los límites de detección y cuantificación estandarizados hacen de esta metodología una excelente herramienta para el seguimiento terapéutico de pacientes tratados con voriconazol o en profilaxis con este fármaco.

Asunto(s)

Humanos , Cromatografía Líquida de Alta Presión , Voriconazol , Antifúngicos , Monitoreo de Drogas

RESUMEN

ABSTRACT Objective This study aimed to verify oral candidiasis, identify the causative species, and investigate the antifungal susceptibility of yeasts isolated from liver transplant patients. Methods A descriptive analysis of 97 patients who underwent liver transplantation was conducted at a hospital. Two clinical examinations (Collections A and B) of the oral cavity were performed. Oral material was collected from all patients, inoculated in Sabouraud Dextrose Agar, and incubated at 35℃ for 48 hours. Samples were identified by molecular sequencing of the internal trascribed space region of rDNA. Results An antifungal susceptibility test with fluconazole, amphotericin B, and micafungin was performed using the Clinical and Laboratory Standards Institute yeast broth microdilution method. Among the patients, 15 presented with oral candidiasis: eight in Collection A and seven in Collection B. The primary type of candidiasis was atrophic, followed by pseudomembranous candidiasis. The most prevalent species was Candida albicans (nine), followed by Candida glabrata (three), Candida tropicalis (two), and Candida dubliniensis (one). Regarding susceptibility to fluconazole, of the 15 samples, 11 were susceptible, three were susceptible in a dose-dependent manner, and one was resistant. Conclusion The most commonly identified type of candidiasis was atrophic, with C. albicans and C. glabrata being the most prevalent causative species. One fluconazole-resistant isolate each of C. tropicalis and C. albicans were identified.

RESUMEN

Introducción: La Dichrostachys cinerea L. (marabú) es una planta que crece en Cuba, de la que se estudian propiedades medicinales. La resistencia de levaduras del género Candida a los antifúngicos sintéticos disponibles en la actualidad es cada vez mayor, por lo que se buscan nuevos compuestos de origen vegetal que puedan ser eficaces en el tratamiento de infecciones causadas por este germen. Objetivo: Evaluar la actividad antifúngica in vitro de Dichrostachys cinerea L. contra una cepa de Candida albicans. Métodos: Se realizó un estudio observacional analítico transversal in vitro para evaluar la actividad antifúngica de extractos fluidos de hojas y de tallos de D. cinerea L mediante el método de macrodilución en caldo y como sustancia de referencia el alcohol. Resultados: A través del proceso se mostró la actividad antifúngica del extracto fluido de tallos de D. cinerea L. al 50 % hasta la dilución 1/32, determinada como la concentración mínima inhibitoria; el extracto fluido de hojas al 30 % no logró inhibir el crecimiento de la cepa de Candida albicans ATCC 10231. Conclusiones: La actividad antifúngica del extracto fluido al 50 % de las hojas de Dichrostachys cinerea L. fue efectiva, no así el preparado farmacéutico al 30 %. Se determinó la concentración mínima inhibitoria del extracto fluido de hojas al 50 % y se demostró que ésta superó a la del alcohol al 50 % en tres diluciones contra la Candida albicans.

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Introduction: Dichrostachys cinerea L. (marabou) is a plant that grows in Cuba, medicinal properties of this plant are being studied. The resistance of yeasts of the Candida genus to current available synthetic antifungals is increasingly greater. This is why, new compounds of plant origin are being searched for the effective treatment of infections caused by this germ. Objective: To evaluate the in vitro antifungal activity of Dichrostachys cinerea L against a strain of Candida albicans. Methods: An in vitro a cross-sectional analytic observational study was carried out to evaluate the antifungal activity of fluid extracts of D. cinerea L leaves and stems using the broth macro-dilution method and alcohol as the reference substance. Results: Through the process was shown the antifungal activity of the fluid extract of Dichrostachys cinerea L. stems at 50% up to the 1/32 dilution; it was determined as the minimum inhibitory concentration. The leaves fluid extract at 30% failed to inhibit the growth of the Candida albicans ATCC 10231 strain. Conclusions: The antifungal activity of the fluid extract at 50% of the leaves was effective, but not the pharmaceutical preparation at 30%. The minimum inhibitory concentration of the fluid extract of leaves at 50% was determined and it was shown that it exceeded that of alcohol at 50% in three dilutions against Candida albicans.

RESUMEN

BACKGROUND: This research evaluated the anti-Candida albicans effect of Mexican propolis from Chihuahua. Chemical composition of the ethanolic extract of propolis was determined by GC-MS, HPLC-DAD, and HPLC-MS. The presence of anthraquinone, aromatic acid, fatty acids, flavonoids, and carbohydrates was revealed. RESULTS: The anti-Candida activity of propolis was determined. The inhibitions halos were between 10.0 to 11.8 mm; 25% minimum inhibitory concentration (0.5 mg/ml) was fungistatic, and 50% minimum inhibitory concentration (1.0 mg/ml) was fungicidal. The effect of propolis on the capability of C. albicans to change its morphology was evaluated. 25% minimum inhibitory concentration inhibited to 50% of germ tube formation. Staining with calcofluor-white and propidium iodide was performed, showing that the propolis affected the integrity of the cell membrane. INT1 gene expression was evaluated by qRT-PCR. Propolis significantly inhibited the expression of the INT1 gene encodes an adhesin (Int1p). Chihuahua propolis extract inhibited the proliferation of Candida albicans, the development of the germ tube, and the synthesis of adhesin INT1. CONCLUSIONS: Given the properties demonstrated for Chihuahua propolis, we propose that it is a candidate to be considered as an ideal antifungal agent to help treat this infection since it would not have the toxic effects of conventional antifungals.

Asunto(s)

Candida albicans , Própolis , Própolis/farmacología , Própolis/química , Factores de Virulencia , México , Antifúngicos/farmacología , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Proliferación Celular