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1.
Biofouling ; 39(7): 719-729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37698054

RESUMO

The present study aimed to: (1) evaluate the influence of the steroid hormones (SH) on biofilm development; (2) investigate the formation of persister cells (PC) in biofilms; and (3) investigate the influence of SH on PC formation. Biofilms were derived from vulvovaginal candidiasis (VVC) samples and evaluated by three models: microcosm biofilms grown in Vaginal Fluid Simulator Medium (MiB-VFSM); monospecies biofilms grown in VFSM (MoB-VFSM) and RPMI media (MoB-RPMI). SH altered cell counting and biomass of biofilms grown in VSFM; MoB-RPMI were negatively affected by SH. SH stimulated the formation of PC in MiB-VFSM but not MoB-VFSM; MoB-RPMI showed a lower number of PC in the presence of SH. The results showed that SH altered the dynamics of biofilm formation and development, depending on the study model. The data suggest the influence of hormones on the physiology of Candida biofilms and reinforce the importance of PC in the pathogenesis of VVC.

3.
Microbiology (Reading) ; 167(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33427606

RESUMO

Chlamydoconidium-producing Trichophyton tonsurans strains isolated in Northeastern Brazil have morphological features different from the classic description of this dermatophyte species. This study investigated the phylogenetic relationship of chlamydoconidium-producing T. tonsurans strains isolated in Northeastern Brazil. Also, the effect of terbinafine and farnesol on mature biofilms of T. tonsurans strains was evaluated. The mass spectra of T. tonsurans strains were investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The ITS and LSU loci regions of rDNA and the partial ß-tubulin gene were sequenced and the phylogenetic tree was analysed. The effects of terbinafine and farnesol on mature T. tonsurans biofilms were evaluated through the analysis of metabolic activity, quantification of biomass and observation by scanning electron microscopy. MALDI-TOF MS spectra of the chlamydoconidium-producing T. tonsurans strains differed from the spectrum of the control strain (ATCC 28942), presenting an intense ion peak at m/z 4155 Da. Phylogenetic tree analysis showed that the chlamydoconidium-producing strains isolated in Northeastern Brazil are allocated to a single cluster, differing from strains isolated from other countries. As for mature T. tonsurans biofilms, farnesol reduced biomass and metabolic activity by 64.4 and 65.9 %, respectively, while terbinafine reduced the biomass by 66.5 % and the metabolic activity by 69 %. Atypical morphological characteristics presented by chlamydoconidium-producing T. tonsurans strains result from phenotypic plasticity, possibly for adaptation to environmental stressors. Also, farnesol had inhibitory activity against T. tonsurans biofilms, demonstrating this substance can be explored for development of promising anti-biofilm drugs against dermatophytes.


Assuntos
Antifúngicos/farmacologia , Arthrodermataceae/classificação , Biofilmes/efeitos dos fármacos , Filogenia , Arthrodermataceae/citologia , Arthrodermataceae/efeitos dos fármacos , Arthrodermataceae/fisiologia , Biofilmes/crescimento & desenvolvimento , Brasil , DNA Fúngico/genética , DNA Ribossômico/genética , Farneseno Álcool/farmacologia , Proteínas Fúngicas/genética , Humanos , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Esporos Fúngicos/classificação , Esporos Fúngicos/citologia , Terbinafina/farmacologia , Tubulina (Proteína)/genética
4.
PLoS Negl Trop Dis ; 14(3): e0008151, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32226021

RESUMO

Sporothrix chilensis is a mild-pathogenical specie of Sporothrix pallida complex, until now, known as restrict to Chile. Herein, we describe the first clinical isolates identified as S. chilensis in Brazil, preserved in the URM Culture Collection, by polyphasic taxonomy, and their respective antifungal profile of this emergent fungus.


Assuntos
Sporothrix/classificação , Sporothrix/isolamento & purificação , Esporotricose/microbiologia , Antifúngicos/farmacologia , Brasil , Humanos , Testes de Sensibilidade Microbiana , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Sporothrix/genética , Sporothrix/fisiologia , Tubulina (Proteína)/genética
5.
Rev Inst Med Trop Sao Paulo ; 60: e75, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30462798

RESUMO

Coccidioidomycosis is a fungal infection caused by Coccidioides immitis or Coccidioides posadasii. These fungi are known to thrive in desert climate. Fungi produce infectious arthroconidia in soil, they are aerosolized in the air and when inhaled by humans, usually cause infections such as pneumonia. The first cases of coccidioidomycosis in Brazil were reported in 1978. Since then, there have been other reports mainly from desert regions of Northeastern Brazil. The present report describes three cases of coccidioidomycosis on male farmers from Serra Talhada county, Pernambuco State, who developed pneumonia and were subsequently diagnosed with pulmonary coccidioidomycosis. These three farmers were successfully treated with oral fluconazole. They reported having hunted armadillos in a rural and arid area of Pernambuco State. Armadillos are known to be carriers of Coccidioides. This is the first report of infection caused by Coccidioides in Pernambuco State, Brazil.


Assuntos
Coccidioidomicose/diagnóstico , Pneumopatias Fúngicas/diagnóstico , Adulto , Idoso , Animais , Antifúngicos/uso terapêutico , Tatus/microbiologia , Coccidioidomicose/tratamento farmacológico , Coccidioidomicose/transmissão , Fluconazol/uso terapêutico , Humanos , Pneumopatias Fúngicas/tratamento farmacológico , Pneumopatias Fúngicas/transmissão , Masculino
6.
Biofouling ; 33(8): 640-650, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28871863

RESUMO

This study evaluated the effect of the protease inhibitor ritonavir (RIT) on Trichosporon asahii and Trichosporon inkin. Susceptibility to RIT was assessed by the broth microdilution assay and the effect of RIT on protease activity was evaluated using azoalbumin as substrate. RIT was tested for its anti-biofilm properties and RIT-treated biofilms were assessed regarding protease activity, ultrastructure and matrix composition. In addition, antifungal susceptibility, surface hydrophobicity and biofilm formation were evaluated after pre-incubation of planktonic cells with RIT for 15 days. RIT (200 µg ml-1) inhibited Trichosporon growth. RIT (100 µg ml-1) also reduced protease activity of planktonic and biofilm cells, decreased cell adhesion and biofilm formation, and altered the structure of the biofilm and the protein composition of the biofilm matrix. Pre-incubation with RIT (100 µg ml-1) increased the susceptibility to amphotericin B, and reduced surface hydrophobicity and cell adhesion. These results highlight the importance of proteases as promising therapeutic targets and reinforce the antifungal potential of protease inhibitors.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Inibidores da Protease de HIV/farmacologia , Plâncton/efeitos dos fármacos , Ritonavir/farmacologia , Trichosporon/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Interações Medicamentosas , Testes de Sensibilidade Microbiana , Peptídeo Hidrolases/metabolismo , Plâncton/crescimento & desenvolvimento , Plâncton/metabolismo , Trichosporon/crescimento & desenvolvimento , Trichosporon/metabolismo
7.
Braz. j. infect. dis ; 19(6): 660-663, Nov.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769617

RESUMO

ABSTRACT Infections caused by emerging Cryptococcus non-neoformans species are being reported with increasingly frequency. Here, we present a case of fungaemia byCryptococcus laurentii in a woman receiving aggressive immunosuppressive therapy for cervical neoplasia. Three venous blood samples were aseptically collected on consecutive days and C. laurentiiwas isolated and identified through phenotypic and molecular methods. After central venous catheter removal and appropriate antifungal therapy, the patient showed significant improvement and blood culture became negative. Thus, patients following immunosuppressive therapies and using invasive medical devices are at risk of C. laurentii blood infections.


Assuntos
Adulto , Feminino , Humanos , Displasia do Colo do Útero/complicações , Criptococose/microbiologia , Fungemia/microbiologia , Hospedeiro Imunocomprometido/imunologia , Neoplasias do Colo do Útero/complicações , Displasia do Colo do Útero/microbiologia , Criptococose/diagnóstico , Criptococose/imunologia , Cryptococcus/genética , Cryptococcus/isolamento & purificação , Fungemia/diagnóstico , Fungemia/imunologia , Neoplasias do Colo do Útero/microbiologia
8.
Braz J Infect Dis ; 19(6): 660-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26361842

RESUMO

Infections caused by emerging Cryptococcus non-neoformans species are being reported with increasingly frequency. Here, we present a case of fungaemia by Cryptococcus laurentii in a woman receiving aggressive immunosuppressive therapy for cervical neoplasia. Three venous blood samples were aseptically collected on consecutive days and C. laurentii was isolated and identified through phenotypic and molecular methods. After central venous catheter removal and appropriate antifungal therapy, the patient showed significant improvement and blood culture became negative. Thus, patients following immunosuppressive therapies and using invasive medical devices are at risk of C. laurentii blood infections.


Assuntos
Criptococose/microbiologia , Fungemia/microbiologia , Hospedeiro Imunocomprometido/imunologia , Displasia do Colo do Útero/complicações , Neoplasias do Colo do Útero/complicações , Adulto , Criptococose/diagnóstico , Criptococose/imunologia , Cryptococcus/genética , Cryptococcus/isolamento & purificação , Feminino , Fungemia/diagnóstico , Fungemia/imunologia , Humanos , Neoplasias do Colo do Útero/microbiologia , Displasia do Colo do Útero/microbiologia
10.
Rev Soc Bras Med Trop ; 42(2): 188-91, 2009.
Artigo em Português | MEDLINE | ID: mdl-19448940

RESUMO

Yeast infections are common in immunocompromised patients, although emerging species have been changing the epidemiological profile. The ability to secrete proteinases has been associated with pathogenicity within the genus Candida. This study had the aims of diagnosing yeast infections in immunocompromised patients and evaluating the virulence of the etiological agents, based on a proteinase secretion assay using bovine serum albumin as a substrate. Out of a total of 104 patients studied, 19 presented episodes of yeast infection. The respiratory tract (63.2%), followed by the urinary tract (10.5%), were the most common sites of infection. Candida albicans, Candida parapsilosis, Candida tropicalis and emerging species such as Candida krusei and Candida guilliermondii were isolated. Five isolates of Candida parapsilosis and one of Candida albicans and Candida guilliermondii exhibited high enzymatic activity. We conclude that enzymatic characterization of Candida isolates may be a useful prognostic marker, especially among immunocompromised individuals, since yeast infections in such patients are generally serious.


Assuntos
Candida/enzimologia , Candidíase/enzimologia , Peptídeo Hidrolases/biossíntese , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Candida/classificação , Candida/patogenicidade , Candidíase/imunologia , Candidíase/microbiologia , Bovinos , Feminino , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Virulência , Adulto Jovem
11.
Rev. Soc. Bras. Med. Trop ; 42(2): 188-191, Mar.-Apr. 2009. tab
Artigo em Português | LILACS | ID: lil-512927

RESUMO

Infecções por leveduras são freqüentes em imunocomprometidos, contudo espécies emergentes têm alterado o perfil epidemiológico. A habilidade de secretar proteases tem sido associada à patogenicidade do gênero Candida. Esta pesquisa teve como objetivos diagnosticar leveduroses em pacientes imunocomprometidos e avaliar a virulência dos agentes etiológicos baseado em teste de secreção de protease utilizando soro de albumina bovina como substrato. Do total de 104 pacientes estudados, 19 apresentaram episódios de leveduroses. O trato respiratório (63,2 por cento), seguido pelo trato urinário (10,5 por cento) foram os locais mais comuns de infecção. Candida albicans, Candida parapsilosis, Candida tropicalis e espécies emergentes como Candida krusei e Candida guilliermondii foram isoladas. Cinco isolados de Candida parapsilosis e um de Candida albicans e Candida guilliermondii exibiram alta atividade enzimática. Concluímos que a caracterização enzimática de isolados de Candida pode ser um útil marcador prognóstico, especialmente em imunocomprometidos, uma vez que leveduroses nestes pacientes são geralmente graves.


Yeast infections are common in immunocompromised patients, although emerging species have been changing the epidemiological profile. The ability to secrete proteinases has been associated with pathogenicity within the genus Candida. This study had the aims of diagnosing yeast infections in immunocompromised patients and evaluating the virulence of the etiological agents, based on a proteinase secretion assay using bovine serum albumin as a substrate. Out of a total of 104 patients studied, 19 presented episodes of yeast infection. The respiratory tract (63.2 percent), followed by the urinary tract (10.5 percent), were the most common sites of infection. Candida albicans, Candida parapsilosis, Candida tropicalis and emerging species such as Candida krusei and Candida guilliermondii were isolated. Five isolates of Candida parapsilosis and one of Candida albicans and Candida guilliermondii exhibited high enzymatic activity. We conclude that enzymatic characterization of Candida isolates may be a useful prognostic marker, especially among immunocompromised individuals, since yeast infections in such patients are generally serious.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Bovinos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Candida/enzimologia , Candidíase/enzimologia , Peptídeo Hidrolases/biossíntese , Candida/classificação , Candida/patogenicidade , Candidíase/imunologia , Candidíase/microbiologia , Hospedeiro Imunocomprometido , Virulência , Adulto Jovem
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