Antifungal Activity of Nontoxic Nanocomposite Based on Silver and Reduced Graphene Oxide against Dermatophytes and Candida spp.

Dermatomycoses are typical hair, skin, or nail infections caused mainly by dermatophytes and nondermatophytes: Trichophyton, Microsporum, Epidermophyton, and Candida. In addition to the esthetical impact, pain, and nail deformity, these mycoses can be a source of severe disease. The high cost of treatment, toxicity, and the emergence of resistant infectious agents justifies research into new drugs. This work evaluates the fungicidal activity of nanocomposites (NCs) based on reduced graphene oxide (rGO) loaded with silver (Ag) nanoparticles (rGO/Ag) against clinical isolates of dermatophytes and Candida species. This is an unprecedented study in which, for the first time, hybrid nanocompounds based on Ag/rGO were tested against Epidermophytom, Microsporum, and Trichophyton species (dermatophytes agents). In this paper, we synthesize rGO using different concentrations of Ag by hydrolysis of metal salt AgNO3 and follow the growth of nanocrystals on sheets of rGO provided by the NaBH4. The NCs were analyzed by X-ray diffraction analysis, and the NC morphology, silver distribution on the rGO surface, and crystalline information were investigated by transmission electron microscopy. Antifungal susceptibility assay was performed by the microdilution method based on modified Clinical and Laboratory Standards Institute (CLSI) protocol. Time-kill kinetics was conducted to monitor the effect of the composite to inhibit fungal cells or promote structural changes, avoiding germination. The toxicological evaluation of the NCs was born in an in vivo model based on Galleria mellonella (G. mellonella). Minimum inhibitory concentration (MIC) values of the rGO/Ag NCs ranged from 1.9 to 125 µg/mL. The best inhibitory activity was obtained for rGO/Ag12%, mainly against Candida spp. and Epidermophyton floccosum. In the presence of sorbitol, MIC values of rGO/Ag NCs were higher (ranging from 15.6 to 250 µg/mL), indicating the action mechanism on the cell wall. Both yeast and dermatophytes clinical isolates were inhibited at a minimum of 6 and 24 h, respectively, but after 2 and 12 h, they had initial antifungal interference. All hybrid formulations of rGO/Ag NCs were not toxic for G. mellonella. This study provides insights into an alternative therapeutic strategy for controlling dermatomycoses.

Combinatorial effect of fluconazole, itraconazole, and terbinafine with different culture extracts of Candida parapsilosis and Trichophyton spp. against Trichophyton rubrum.

Onychomycosis is a nail infection caused by dermatophytes, non-dermatophyte fungi, and yeasts, especially Candida species. The present study evaluated the combinatorial effect of different cultured extracts of Candida parapsilosis and Trichophyton mentagrophytes and Trichophyton rubrum with fluconazole, itraconazole, and terbinafine against clinical isolates of Trichophyton rubrum. In addition, investigation of the action of the extracts on the wall or membrane was performed. Pure and mixed cultures of Candida parapsilosis and dermatophytes were filtered through a 0.2-µm membrane and submitted to liquid-liquid extraction using ethyl acetate. After a checkerboard, trial with drugs was performed to evaluate the synergistic interaction with the extract. The results obtained for the minimum inhibitory concentration (MIC) of extracts against the T. rubrum strain in isolation were 500-8000 µg/mL. The MIC range for fluconazole, itraconazole, and terbinafine were 2-32 µg/mL, 0.25-0.5 µg/mL, 0.03-64 µg/mL, respectively. However, when the extract was combined with drugs, the MIC values decreased: extracts 1.9-1000 µg/mL, fluconazole 0.25-4, itraconazole 0.03-0.06 µg/mL, and terbinafine 0.001-0.02 µg/mL. The MIC values of the extracts in the Roswell Park Memorial Institute 1640 medium (RPMI) supplemented with sorbitol did not change, suggesting any action on the cell wall. However, in the presence of RPMI supplemented with ergosterol, MIC values of the extracts increased by up to 2×, indicating action on the fungal cell membrane. A synergistic action was observed between products and drugs, detecting a decrease in MIC values. There is potential and a new therapeutic perspective for fungal control.

Sporothrix pathogenic clade: Molecular analysis of animal and human clinical isolates.

Sporotrichosis is a subcutaneous mycosis that affects animals and humans. Varying in severity, occurrences range from local lesions to systemic involvement. It is caused by thermodimorphic and saprobic fungi from the Sporothrix pathogenic clade. This study aimed to identify the species and the sexual idiomorph distribution patterns responsible for diagnosed cases of sporotrichosis in São José do Rio Preto, Brazil. We included 188 isolates of Sporothrix sp. from feline lesions and 27 of human origin, which underwent molecular identification and genotyping for mating-type MAT1-1 and MAT1-2. The results showed that Sporothrix brasiliensis is the prevalent species in feline sporotrichosis outbreaks with the overwhelming presence of a single mating-type, MAT1-2 (P <.0001), suggesting a prevalently clonal form of spread. Morphological analyses did not discriminate among cryptic species in the genus Sporothrix, and molecular identification was essential for the correct identification of the species responsible for the observed cases of sporotrichosis. Distribution analyses of MAT1-2 isolates support the hypothesis of unidirectional migration from the current epidemics in São Paulo and Rio de Janeiro to the municipality of São José do Rio Preto.

This study aimed to identify the species and the sexual idiomorph distribution patterns responsible for diagnosed cases of sporotrichosis in São José do Rio Preto, Brazil. We included 188 isolates of Sporothrix sp. from feline lesions and 27 of human origin.

Clinical and epidemiological aspects of feline sporotrichosis caused by Sporothrix brasiliensis and in vitro antifungal susceptibility.

Sporotrichosis is a subcutaneous mycosis resulting from the traumatic implantation of pathogenic Sporothrix species. In Brazil, zoonotic transmission plays an important role in the epidemiology of the disease, involving especially cats. The objective of this study was to isolate Sporothrix spp. from cats with signs of sporotrichosis, determining the causative species, clinical and epidemiological aspects, and the in vitro susceptibility profile of the isolates against antifungal drugs. From September 2017 to February 2019, 245 samples of lesions were collected from symptomatic cats in São José do Rio Preto, Brazil. Identification of the isolates was performed by morphophysiological parameters and species-specific polymerase chain reaction. The susceptibility profile of the isolates was determined for five drugs (amphotericin B, itraconazole, ketoconazole, potassium iodide and terbinafine), using the broth microdilution method. Clinical and epidemiological aspects were analyzed based on data contained on investigation forms filled by the veterinarians at moment of collection. Sporothrix spp. were isolated in 189 (77.2%) of the samples. Phenotypic and molecular analyses revealed S. brasiliensis as the only causative agent. In vitro susceptibility testing showed lower MIC values for terbinafine (MIC = 0.03-2 µg/ml), ketoconazole (MIC = 0.03-2 µg/ml), and itraconazole (MIC = 0.03-4 µg/ml). Most of the animals were male (73.5%), adults (96.3%), stray (53.5%), and uncastrated (69.8%). Our results show the expansion of the S. brasiliensis epidemic to an area nearly 840 km apart from the epicenter of the long-lasting outbreak of cat-transmitted sporotrichosis in Rio de Janeiro.

Epidemiological profile of patients with congenital and gestational syphilis in a city in the State of São Paulo, Brazil / Perfil epidemiológico de pacientes com sífilis congênita e gestacional em um município do Estado de São Paulo, Brasil

Abstract Objectives: to assess the epidemiological profile of congenital and syphilis during pregnancy in residents of São José do Rio Preto in São Paulo State. Methods: ecological study of the epidemiological profile of patients with congenital and gestational syphilis, based on the Sistema de Informação de Agravos de Notificação (Information System for Notifiable Diseases) from 2007 to 2016. Results: there were 396 cases of syphilis reported in pregnant women and 290 of congenital syphilis. In 2016, the rate of detecting syphilis in pregnant women was 13.2 cases/1,000 live births, while congenital syphilis the incidence rate was 6.5 cases/1,000 live births. For gestational syphilis, 54% of the diagnosis was performed in 2nd or 3rd trimester and 85% were reported at the primary care. Adequate treatment for pregnant women occurred in 96% of the notifications with 52% of partners treated. In congenital syphilis, 82% of the mothers underwent prenatal care. However, 94% of the pregnant women were treated inadequately while 82% of the partners did not receive any treatment. Conclusions: there has been an increase in the number of cases of gestational syphilis in pregnant women and a decrease in the cases of congenital syphilis from 2014. These results showed that the goal of 0.5 case/1,000 live births proposed by World Health Organization is still far from being achieved in this city.

Resumo Objetivos: conhecer o perfil epidemiológico da sífilis congênita e em gestantes nos residentes de São José do Rio Preto/SP. Métodos: estudo ecológico do perfil epidemiológico dos pacientes com sífilis congênita e gestacional, a partir de dados coletados no Sistema de Informação de Agravos de Notificação entre 2007 e 2016. Resultados: foram notificados 396 casos de sífilis em gestantes e 290 de sífilis congênita. Em 2016, a taxa de detecção da sífilis em gestantes foi 13,2 casos/1.000 nascidos vivos, enquanto a sífilis congênita, a taxa de incidência foi 6,5 casos/1.000 nascidos vivos. Para sífilis gestacional, 54% do diagnóstico foram realizados no 2° ou 3° trimestre e 85% notificadas na atenção primária. O tratamento adequado das gestantes ocorreu em 97% das notificações, com 52% dos parceiros tratados. Na sífilis congênita, 82% das mães realizaram o pré-natal, entretanto, 94% das gestantes foram tratadas inadequadamente e 82% dos parceiros não realizaram o tratamento. Conclusões: foi observado o aumento no número de casos de sífilis em gestantes e uma queda dos casos de sífilis congênita a partir de 2014. Com esses resultados, é notório que a meta de 0,5 caso/1.000 nascidos vivos proposta pela Organização Mundial da Saúde ainda está distante de ser alcançada no município.