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1.
PLoS Genet ; 16(8): e1009005, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32841236

RESUMO

Azole drugs are the most frequently used antifungal agents. The pathogenic yeast Candida glabrata acquires resistance to azole drugs via single amino acid substitution mutations eliciting a gain-of-function (GOF) hyperactive phenotype in the Pdr1 transcription factor. These GOF mutants constitutively drive high transcription of target genes such as the ATP-binding cassette transporter-encoding CDR1 locus. Previous characterization of Pdr1 has demonstrated that this factor is negatively controlled by the action of a central regulatory domain (CRD) of ~700 amino acids, in which GOF mutations are often found. Our earlier experiments demonstrated that a Pdr1 derivative in which the CRD was deleted gave rise to a transcriptional regulator that could not be maintained as the sole copy of PDR1 in the cell owing to its toxically high activity. Using a set of GOF PDR1 alleles from azole-resistant clinical isolates, we have analyzed the mechanisms acting to repress Pdr1 transcriptional activity. Our data support the view that Pdr1-dependent transactivation is mediated by a complex network of transcriptional coactivators interacting with the extreme C-terminal part of Pdr1. These coactivators include but are not limited to the Mediator component Med15A. Activity of this C-terminal domain is controlled by the CRD and requires multiple regions across the C-terminus for normal function. We also provide genetic evidence for an element within the transactivation domain that mediates the interaction of Pdr1 with coactivators on one hand while restricting Pdr1 activity on the other hand. These data indicate that GOF mutations in PDR1 block nonidentical negative inputs that would otherwise restrain Pdr1 transcriptional activation. The strong C-terminal transactivation domain of Pdr1 uses multiple different protein regions to recruit coactivators.


Assuntos
Candida glabrata/efeitos dos fármacos , Candidíase/tratamento farmacológico , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Antifúngicos/efeitos adversos , Antifúngicos/farmacologia , Azóis/efeitos adversos , Azóis/farmacologia , Candida glabrata/genética , Candida glabrata/patogenicidade , Candidíase/genética , Candidíase/microbiologia , Proteínas de Ligação a DNA , Farmacorresistência Fúngica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Ativação Transcricional/efeitos dos fármacos
2.
PLoS Pathog ; 16(8): e1008695, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32750090

RESUMO

The NLRP3 inflammasome has emerged as a central immune regulator that senses virulence factors expressed by microbial pathogens for triggering inflammation. Inflammation can be harmful and therefore this response must be tightly controlled. The mechanisms by which immune cells, such as macrophages, discriminate benign from pathogenic microbes to control the NLRP3 inflammasome remain poorly defined. Here we used live cell imaging coupled with a compendium of diverse clinical isolates to define how macrophages respond and activate NLRP3 when faced with the human yeast commensal and pathogen Candida albicans. We show that metabolic competition by C. albicans, rather than virulence traits such as hyphal formation, activates NLRP3 in macrophages. Inflammasome activation is triggered by glucose starvation in macrophages, which occurs when fungal load increases sufficiently to outcompete macrophages for glucose. Consistently, reducing Candida's ability to compete for glucose and increasing glucose availability for macrophages tames inflammatory responses. We define the mechanistic requirements for glucose starvation-dependent inflammasome activation by Candida and show that it leads to inflammatory cytokine production, but it does not trigger pyroptotic macrophage death. Pyroptosis occurs only with some Candida isolates and only under specific experimental conditions, whereas inflammasome activation by glucose starvation is broadly relevant. In conclusion, macrophages use their metabolic status, specifically glucose metabolism, to sense fungal metabolic activity and activate NLRP3 when microbial load increases. Therefore, a major consequence of Candida-induced glucose starvation in macrophages is activation of inflammatory responses, with implications for understanding how metabolism modulates inflammation in fungal infections.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Glucose/deficiência , Interações Hospedeiro-Patógeno/imunologia , Inflamação/imunologia , Macrófagos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/fisiologia , Animais , Células 3T3 BALB , Candida albicans/metabolismo , Candidíase/metabolismo , Candidíase/microbiologia , Caspase 1/fisiologia , Caspases Iniciadoras/fisiologia , Feminino , Hifas , Inflamação/metabolismo , Inflamação/microbiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas de Ligação a Fosfato/fisiologia , Piroptose
3.
PLoS Pathog ; 16(8): e1008414, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32776983

RESUMO

The host innate immune system has developed elegant processes for the detection and clearance of invasive fungal pathogens. These strategies may also aid in the spread of pathogens in vivo, although technical limitations have previously hindered our ability to view the host innate immune and endothelial cells to probe their roles in spreading disease. Here, we have leveraged zebrafish larvae as a model to view the interactions of these host processes with the fungal pathogen Candida albicans in vivo. We examined three potential host-mediated mechanisms of fungal spread: movement inside phagocytes in a "Trojan Horse" mechanism, inflammation-assisted spread, and endothelial barrier passage. Utilizing both chemical and genetic tools, we systematically tested the loss of neutrophils and macrophages and the loss of blood flow on yeast cell spread. Both neutrophils and macrophages respond to yeast-locked and wild type C. albicans in our model and time-lapse imaging revealed that macrophages can support yeast spread in a "Trojan Horse" mechanism. Surprisingly, loss of immune cells or inflammation does not alter dissemination dynamics. On the other hand, when blood flow is blocked, yeast can cross into blood vessels but they are limited in how far they travel. Blockade of both phagocytes and circulation reduces rates of dissemination and significantly limits the distance of fungal spread from the infection site. Together, this data suggests a redundant two-step process whereby (1) yeast cross the endothelium inside phagocytes or via direct uptake, and then (2) they utilize blood flow or phagocytes to travel to distant sites.


Assuntos
Candida albicans/imunologia , Candidíase/imunologia , Células Endoteliais/imunologia , Interações Hospedeiro-Patógeno/imunologia , Neutrófilos/imunologia , Fagócitos/imunologia , Peixe-Zebra/microbiologia , Animais , Candidíase/microbiologia , Larva , Macrófagos/imunologia , Macrófagos/microbiologia , Neutrófilos/microbiologia , Fagócitos/microbiologia
4.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 40(7): 1049-1055, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32701244

RESUMO

OBJECTIVE: To investigate the characteristics of growth and metabolism and the in vivo toxicity of Candida auris under different conditions. METHODS: We observed the growth of Candida auris and Candida albicans under routine culture conditions and in different pH and salt concentrations, and compared their activities of sugar fermentation using microbiochemical reaction tubes. Four-week-old nude mice were randomized into Candida auris infection group (n=5), Candida albicans infection group (n=5) and control group (n=5) for intragastric administration of 0.3 mL suspension the two Candida species (5×109 cfu/mL) or 0.3 mL normal saline. Samples of the liver, kidney, intestine, feces and blood were taken for analysis of the in vivo distribution and toxicity of Candida albicans by fungal culture and histopathological examination. RESULTS: Candida auris exhibited logarithmic growth at 8-24 h after inoculation and showed stable growth after 24 h. Candida auris showed optimal growth within the pH value range of 5-7 with a growth pattern identical to that of Candida albicans. Candida auris grew better than Candida albicans in media containing 5% and 10% NaCl, and could ferment glucose, sucrose, trehalose and sorbitol. Candida auris could be isolated from the feces, blood, liver and kidney of infected nude mice, and the liver had the highest fungal load (5.7 log10 cfu/g). Candida auris could cause pathological changes in the liver and intestine of the mice, but with a lesser severity as compared with Candida albicans. CONCLUSIONS: Candida auris exhibits optimal growth in mildly acidic or neutral conditions with a high salt tolerance, and can potentially penetrate the intestinal barrier into blood and lead to tissue injuries in hosts with immunosuppression.


Assuntos
Candida , Candidíase , Animais , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Meios de Cultura , Camundongos , Camundongos Nus , Distribuição Aleatória
5.
J Laryngol Otol ; 134(7): 592-596, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32713390

RESUMO

BACKGROUND: Fungal otitis externa is prevalent in tropical and sub-tropical climates; however, over the past two decades, there has been a reported increase in the prevalence of otomycosis in paediatric patients from more temperate climates. This study aimed to review the children diagnosed with otomycosis at the University Hospital Limerick with reference to frequency, causative organism, predisposing factors and management. METHODS: A retrospective review was conducted of paediatric patients from 2001 to 2015. Patients with positive fungal ear swabs and a diagnosis of otomycosis were identified. RESULTS: Ninety-three patients were positive for candida (mean age, 5.8 years), 10 patients were positive for aspergillus (mean age, 9.1 years) and 1 patient had mixed fungal infection containing both fungi. There was a positive correlation between a diagnosis of otomycosis and prior treatment with topical fluoroquinolones (r = 0.8; p < 0.01). CONCLUSION: The incidence of otomycosis has been increasing since 2001, which correlates with an increase in the use of topical fluoroquinolones. Previous studies identify aspergillus as the commonest causative fungi; however, this study found that candida was the commonest isolated fungi in the paediatric population.


Assuntos
Otomicose/epidemiologia , Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Aspergilose/epidemiologia , Aspergilose/microbiologia , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Candidíase/microbiologia , Criança , Pré-Escolar , Coinfecção/diagnóstico , Coinfecção/tratamento farmacológico , Coinfecção/epidemiologia , Coinfecção/microbiologia , Feminino , Humanos , Incidência , Irlanda/epidemiologia , Masculino , Otomicose/diagnóstico , Otomicose/tratamento farmacológico , Otomicose/microbiologia , Estudos Retrospectivos
6.
PLoS One ; 15(7): e0235746, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32678853

RESUMO

Azole resistant fungal infections remain a health problem for the immune compromised. Current therapies are limited due to rises in new resistance mechanisms. Therefore, it is important to identify new drug targets for drug discovery and novel therapeutics. Arv1 (are1 are2 required for viability 1) function is highly conserved between multiple pathogenic fungal species. Candida albicans (C. albicans) cells lacking CaArv1 are azole hypersusceptible and lack virulence. Saccharomyces cerevisiae (S. cerevisiae) Scarv1 cells are also azole hypersusceptible, a phenotype reversed by expression of CaArv1, indicating conservation in the molecular mechanism for azole susceptibility. To define the relationship between Arv1 function and azole susceptibility, we undertook a structure/function analysis of ScArv1. We identified several conserved amino acids within the ScArv1 homology domain (ScAhd) required for maintaining normal azole susceptibility. Erg11 lanosterol 14-α-demethylase is the rate-limiting enzyme in sterol biosynthesis and is the direct target of azole antifungals, so we used our ScArv1 mutants in order to explore the relationship between ScArv1 and ScErg11. Specific ScArv1 mutants ectopically expressed from a low copy plasmid were unable to restore normal azole susceptibility to Scarv1 cells and had reduced Erg11 protein levels. Erg11 protein stability depended on its ability to form a heterodimeric complex with Arv1. Complex formation was required for maintaining normal azole susceptibility. Scarv1 cells expressing orthologous CaArv1 mutants also had reduced CaErg11 levels, were unable to form a CaArv1-CaErg11 complex, and were azole hypersusceptible. Scarv1 cells expressing CaArv1 mutants unable to interact with CaErg11 could not sustain proper levels of the azole resistant CaErg11Y132F F145L protein. Caarv1/Caarv1 cells expressing CaArv1 mutants unable to interact with CaErg11 were found to lack virulence using a disseminated candidiasis mouse model. Expressing CaErg11Y132F F145L did not reverse the lack of virulence. We hypothesize that the role of Arv1 in Erg11-dependent azole resistance is to stabilize Erg11 protein level. Arv1 inhibition may represent an avenue for treating azole resistance.


Assuntos
Candida albicans/patogenicidade , Candidíase/microbiologia , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Esterol 14-Desmetilase/metabolismo , Virulência , Sequência de Aminoácidos , Animais , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candidíase/tratamento farmacológico , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Homologia de Sequência , Esterol 14-Desmetilase/genética
7.
J Mycol Med ; 30(3): 101011, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32693980

RESUMO

INTRODUCTION: Otomycosis, a superficial fungal infection of the external auditory canal (EAC), is a disease with exceptionally high prevalence. AIM: The aim of this study was to determine the prevalence of otomycosis, the distribution of causative species and to evaluate epidemiological characteristics of these infections. METHODOLOGY: The patients' data were collected from record book and database of mycological examinations conducted at Public Health Institute Nis, Serbia. In the period from 2014 to 2018 samples of 1287 patients with symptoms and signs of EAC infection were investigated. Standard mycological methods were used for isolation and determination of fungi. RESULTS: High prevalence of otomycosis was determined in examined patients (22.7%). However, the prevalence rates did not differ significantly in the studied period (p=0.931). The majority of patients were diagnosed with only unilateral EAC infection (82.9%). Considering all patients with otomycosis, mold infections caused by the genus Aspergillus (143/48.9%) were more frequent than Candida spp. ear infections (133/45.6%), with Aspergillus niger and Candida аlbicans being predominant causative agents. Mixed Aspergillus and Candida otomycosis was established in 16 (5.5%) patients. Otomycosis was more common in male subjects (26.8%, p=0.003) who also suffered from Aspergillus otomycosis more frequently (17.5%, p<0.001). The prevalence of these infections increases with age (p=0.005), while they do not show seasonal pattern (p>0.05). CONCLUSION: Noted high prevalence of otomycosis, with both yeasts and non-dermatophyte molds acting as infectious agents which require different treatment, implies the necessity for further epidemiological monitoring of this form of superficial mycoses.


Assuntos
Otomicose/epidemiologia , Otomicose/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/classificação , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Aspergilose/epidemiologia , Aspergilose/microbiologia , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/isolamento & purificação , Candida/classificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Candida albicans/efeitos dos fármacos , Candida albicans/isolamento & purificação , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Candidíase/microbiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Técnicas de Tipagem Micológica , Otomicose/tratamento farmacológico , Prevalência , Sérvia/epidemiologia , Adulto Jovem
8.
BMC Infect Dis ; 20(1): 438, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32571233

RESUMO

BACKGROUND: Candida sp. osteoarticular infection is rare and most often due to hematogenous seeding during an episode of candidemia in immunocompromised patients. However, the diagnosis can be delayed in patients with subtle symptoms and signs of joint infection without a concurrent episode of candidemia. CASE PRESENTATION: A 75-year-old woman presented with a three-year history of pain and swelling of the left knee. Candida pelliculosa was detected from the intraoperative tissue when the patient had undergone left total knee arthroplasty 32 months ago, but no antifungal treatment was performed. One year after the total knee arthroplasty, C. pelliculosa was repeatedly isolated from the left knee synovial fluid and antifungal treatment comprising amphotericin B deoxycholate and fluconazole was administered. However, joint infection had extended to the adjacent bone and led to progressive joint destruction. The patient underwent surgery for prosthesis removal and received prolonged antifungal treatment with micafungin and fluconazole. CONCLUSIONS: This case shows that C. pelliculosa, an extremely rare non-Candida albicans sp., can cause fungal arthritis and lead to irreversible joint destruction owing to delayed diagnosis and treatment.


Assuntos
Artrite Infecciosa/tratamento farmacológico , Artrite Infecciosa/microbiologia , Candida/patogenicidade , Candidíase/microbiologia , Idoso , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Candida/isolamento & purificação , Candidemia/tratamento farmacológico , Candidemia/etiologia , Candidíase/tratamento farmacológico , Ácido Desoxicólico/uso terapêutico , Remoção de Dispositivo , Combinação de Medicamentos , Feminino , Fluconazol/uso terapêutico , Humanos , Cuidados Intraoperatórios , Prótese Articular , Joelho/microbiologia , Joelho/cirurgia , Micafungina/uso terapêutico , Osteomielite/tratamento farmacológico , Osteomielite/microbiologia
9.
Int J Nanomedicine ; 15: 3681-3693, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547022

RESUMO

Background: Fungal infections are becoming more prevalent and threatening because of the continuous emergence of azole-resistant fungal infections. The present study was aimed to assess the activity of free Methylglyoxal (MG) or MG-conjugated chitosan nanoparticles (MGCN) against fluconazole-resistant Candida albicans. Materials and Methods: A novel formulation of MGCN was prepared and characterized to determine their size, shape and polydispersity index. Moreover, the efficacy of fluconazole or MG or MGCN was determined against intracellular C. albicans in macrophages and the systematic candidiasis in a murine model. The safety of MG or MGCN was tested in mice by analyzing the levels of hepatic and renal toxicity parameters. Results: Candida albicans did not respond to fluconazole, even at the highest dose of 20 mg/kg, whereas MG and MGCN effectively eliminated C. albicans from the macrophages and infected mice. Mice in the group treated with MGCN at a dose of 10 mg/kg exhibited a 90% survival rate and showed the lowest fungal load in the kidney, whereas the mice treated with free MG at the same dose exhibited 50% survival rate. Moreover, the administration of MG or MGCN did not induce any liver and kidney toxicity in the treated mice. Conclusion: The findings of the present work suggest that MGCN may be proved a promising therapeutic formulation to treat azole-resistant C. albicans infections.


Assuntos
Candidíase/tratamento farmacológico , Quitosana/química , Farmacorresistência Fúngica , Fluconazol/uso terapêutico , Nanopartículas/química , Aldeído Pirúvico/uso terapêutico , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Modelos Animais de Doenças , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Fluconazol/farmacologia , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Tamanho da Partícula , Aldeído Pirúvico/farmacologia
10.
BMC Infect Dis ; 20(1): 419, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546213

RESUMO

BACKGROUND: Four new variants of Chlamydia trachomatis (nvCTs), detected in several countries, cause false-negative or equivocal results using the Aptima Combo 2 assay (AC2; Hologic). We evaluated the clinical sensitivity and specificity, as well as the analytical inclusivity and exclusivity of the updated AC2 for the detection of CT and Neisseria gonorrhoeae (NG) on the automated Panther system (Hologic). METHODS: We examined 1004 clinical AC2 samples and 225 analytical samples spiked with phenotypically and/or genetically diverse NG and CT strains, and other potentially cross-reacting microbial species. The clinical AC2 samples included CT wild type (WT)-positive (n = 488), all four described AC2 diagnostic-escape nvCTs (n = 170), NG-positive (n = 214), and CT/NG-negative (n = 202) specimens. RESULTS: All nvCT-positive samples (100%) and 486 (99.6%) of the CT WT-positive samples were positive in the updated AC2. All NG-positive, CT/NG-negative, Trichomonas vaginalis (TV)-positive, bacterial vaginosis-positive, and Candida-positive AC2 specimens gave correct results. The clinical sensitivity and specificity of the updated AC2 for CT detection was 99.7 and 100%, respectively, and for NG detection was 100% for both. Examining spiked samples, the analytical inclusivity and exclusivity were 100%, i.e., in clinically relevant concentrations of spiked microbe. CONCLUSIONS: The updated AC2, including two CT targets and one NG target, showed a high sensitivity, specificity, inclusivity and exclusivity for the detection of CT WT, nvCTs, and NG. The updated AC2 on the fully automated Panther system offers a simple, rapid, high-throughput, sensitive, and specific diagnosis of CT and NG, which can easily be combined with detection of Mycoplasma genitalium and TV.


Assuntos
Infecções por Chlamydia/diagnóstico , Chlamydia trachomatis/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência de RNA/métodos , Candida/genética , Candidíase/diagnóstico , Candidíase/microbiologia , Infecções por Chlamydia/microbiologia , Reações Cruzadas , Feminino , Gonorreia/diagnóstico , Gonorreia/microbiologia , Humanos , Neisseria gonorrhoeae/genética , RNA Bacteriano/genética , RNA Ribossômico 23S/genética , Sensibilidade e Especificidade , Tricomoníase/diagnóstico , Tricomoníase/parasitologia , Trichomonas vaginalis/genética
12.
J Mycol Med ; 30(3): 100968, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32386800

RESUMO

OBJECTIVE: Candida parapsilosis species complex, an important set of non-albicans Candida species, is known to cause candidaemia particularly in neonates and infants. However, the incidence has increased in recent years, owing to higher numbers of at individuals at risk for these infections. Our objective was to evaluate the in vitro susceptibility of clinical isolates of C. parapsilosis complex isolates from Iran to seven antifungal drugs. MATERIAL AND METHODS: One hundred-one clinical isolates of C. parapsilosis species complex cultured from humans were included. Species identification had been previously confirmed by combined phenotypic characteristics, matrix-assisted laser desorption ionization-time of flight mass spectrometry-based assay and reconfirmed by DNA sequence analysis of the ITS rDNA region and D1/D2 gene. Minimum inhibitory concentrations (MICs) for amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, micafungin and anidulafungin were determined against well-characterized isolates by broth microdilution susceptibility testing according to the CLSI M27-A3 guideline. RESULTS: Species identifications were performed on 101 isolates, of which 88 (87.2%) C. parapsilosis sensu stricto and 13 (12.8%) C. orthopsilosis. Amphotericin B and posaconazole were the most active drugs with 100% of isolates being wild-type (WT). Voriconazole and micafungin, 99% of isolates were WT. The low activity was recorded for fluconazole and itraconazole with 93.1% and 89.1% of isolates being WT, respectively. At the species level, all Candida parapsilosis sensu stricto isolates were WT to amphotericin B and posaconazole and all Candida orthopsilosis isolates were WT to amphotericin B, voriconazole, posaconazole, anidulafungin and micafungin. In contrast, the highest rate of non-WT was observed in C. orthopsilosis to itraconazole (4 of 13, 30.8%). CONCLUSIONS: Although almost all of the tested drugs demonstrated potent activity against C. parapsilosis species complex, it seems that more especially C. orthopsilosis isolates had decreased susceptibility to itraconazole. Further studies are needed to determine how these findings may switch into in vivo efficacy.


Assuntos
Antifúngicos/farmacologia , Candida parapsilosis/efeitos dos fármacos , Candidíase/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Candida parapsilosis/crescimento & desenvolvimento , Candida parapsilosis/isolamento & purificação , Candidíase/tratamento farmacológico , Candidíase/epidemiologia , Criança , Pré-Escolar , Farmacorresistência Fúngica/efeitos dos fármacos , Feminino , Humanos , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Adulto Jovem
13.
AAPS PharmSciTech ; 21(5): 140, 2020 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-32419032

RESUMO

The present study is aimed at enhancing the skin penetration of ketoconazole by formulating it as transethosome. Ketoconazole-loaded transethosome formulations were prepared by conventional thin film evaporation and hydration method and were optimized using concentration of edge activator (span 80), ethanol and sonication time as factors and particle size, polydispersity index and entrapment efficiency as responses. The optimized formulation was further evaluated for in vitro diffusion, anti-fungal activity, ex vivo penetration and in vivo pharmacodynamic activity. The results of in vitro drug diffusion and ex vivo skin penetration studies demonstrated that the amount of drug diffused and penetrated through the skin was increased. Optimized transethosomes showed enhanced in vitro antifungal and in vivo pharmacodynamic activities against Candida albicans in Wistar albino rats when compared to conventional liposomes. Therefore, the developed ketoconazole encapsulated transethosome formulation is capable of enhancing the skin penetration of the drug by overcoming the stratum corneum barrier function and acting as an effective drug delivery system for ketoconazole through the skin for its anti-fungal activity.


Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/química , Administração Cutânea , Animais , Antifúngicos/farmacocinética , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Excipientes , Cetoconazol/administração & dosagem , Cetoconazol/química , Lipossomos , Tamanho da Partícula , Ratos , Ratos Wistar , Absorção Cutânea
15.
Can J Microbiol ; 66(6): 377-388, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32319304

RESUMO

Candida tropicalis is a prominent non-Candida albicans Candida species involved in cases of candidemia, mainly causing infections in patients in intensive care units and (or) those presenting neutropenia. In recent years, several studies have reported an increase in the recovery rates of azole-resistant C. tropicalis isolates. Understanding C. tropicalis resistance is of great importance, since resistant strains are implicated in persistent or recurrent and breakthrough infections. In this review, we address the main mechanisms underlying C. tropicalis resistance to the major antifungal classes used to treat candidiasis. The main genetic basis involved in C. tropicalis antifungal resistance is discussed. A better understanding of the epidemiology of resistant strains and the mechanisms involved in C. tropicalis resistance can help improve diagnosis and assessment of the antifungal susceptibility of this Candida species to improve clinical management.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida tropicalis/genética , Candidíase/microbiologia , Farmacorresistência Fúngica/genética , Candida tropicalis/efeitos dos fármacos , Candidíase/diagnóstico , Candidíase/tratamento farmacológico , Humanos
16.
PLoS One ; 15(4): e0229757, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310961

RESUMO

INTRODUCTION: Even though use of antiretroviral therapy (HAART) decreases the incidence of opportunistic infections (OIs) they are continuing to be a major cause of morbidity and mortality. Studies concerning this problem are scarce in Eastern Africa. The aim of this study was to determine the incidence and predictors of OIs after initiation of HAART in Ethiopia. METHODS: A health facility based single centered cohort study using structured data extraction sheet was conducted. The study population was all HIV positive ART naive adolescents and adults who started HAART between January 2009 and May 2012. Simple random sampling technique was used to select 317 patients from the record. Multivariate binary logistic regression model was used to determine factors for the occurrence of OIs after initiation of HAART. RESULTS: The incidence of OIs after HAART was 7.5 cases/100person years. Tuberculosis, oral candidiasis, pneumonia and toxoplasmosis were the leading OIs after HAART. A bed ridden functional status at initiation of HAART, presence of OIs before HAART, non-adherence and low hemoglobin level were predictors for the occurrence of OIs after HAART. CONCLUSION: The incidence of OIs after HAART was higher than in previous studies. Patients with the identified risk factors need strict follow up to reduce the morbidity and mortality attributed to OIs. Earlier initiation of HAART before advanced immune suppression, better management of TB and extended baseline assessment could help to reduce opportunistic infections and mortality after the initiation of HAART in Ethiopian patients.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Candidíase/tratamento farmacológico , Infecções por HIV/tratamento farmacológico , Pneumonia/tratamento farmacológico , Tuberculose/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/complicações , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adolescente , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Candidíase/complicações , Candidíase/microbiologia , Candidíase/virologia , Estudos de Coortes , Etiópia/epidemiologia , Feminino , HIV/patogenicidade , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/complicações , Pneumonia/microbiologia , Pneumonia/virologia , Tuberculose/complicações , Tuberculose/microbiologia , Tuberculose/virologia , Adulto Jovem
17.
Nat Commun ; 11(1): 2031, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341348

RESUMO

Neutrophils employ several mechanisms to restrict fungi, including the action of enzymes such as myeloperoxidase (MPO) or NADPH oxidase, and the release of neutrophil extracellular traps (NETs). Moreover, they cooperate, forming "swarms" to attack fungi that are larger than individual neutrophils. Here, we designed an assay for studying how these mechanisms work together and contribute to neutrophil's ability to contain clusters of live Candida. We find that neutrophil swarming over Candida clusters delays germination through the action of MPO and NADPH oxidase, and restricts fungal growth through NET release within the swarm. In comparison with neutrophils from healthy subjects, those from patients with chronic granulomatous disease produce larger swarms against Candida, but their release of NETs is delayed, resulting in impaired control of fungal growth. We also show that granulocyte colony-stimulating factors (GCSF and GM-CSF) enhance swarming and neutrophil ability to restrict fungal growth, even during treatment with chemical inhibitors that disrupt neutrophil function.


Assuntos
Candida albicans/crescimento & desenvolvimento , Neutrófilos/citologia , Neutrófilos/microbiologia , Sistemas CRISPR-Cas , Candidíase/microbiologia , Linhagem Celular , Armadilhas Extracelulares/metabolismo , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Doença Granulomatosa Crônica/microbiologia , Humanos , Processamento de Imagem Assistida por Computador , Análise em Microsséries , NADPH Oxidases/metabolismo , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
PLoS Pathog ; 16(4): e1008408, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32251450

RESUMO

Candida bloodstream infection, i.e. candidemia, is the most frequently encountered life-threatening fungal infection worldwide, with mortality rates up to almost 50%. In the majority of candidemia cases, Candida albicans is responsible. Worryingly, a global increase in the number of patients who are susceptible to infection (e.g. immunocompromised patients), has led to a rise in the incidence of candidemia in the last few decades. Therefore, a better understanding of the anti-Candida host response is essential to overcome this poor prognosis and to lower disease incidence. Here, we integrated genome-wide association studies with bulk and single-cell transcriptomic analyses of immune cells stimulated with Candida albicans to further our understanding of the anti-Candida host response. We show that differential expression analysis upon Candida stimulation in single-cell expression data can reveal the important cell types involved in the host response against Candida. This confirmed the known major role of monocytes, but more interestingly, also uncovered an important role for NK cells. Moreover, combining the power of bulk RNA-seq with the high resolution of single-cell RNA-seq data led to the identification of 27 Candida-response QTLs and revealed the cell types potentially involved herein. Integration of these response QTLs with a GWAS on candidemia susceptibility uncovered a potential new role for LY86 in candidemia susceptibility. Finally, experimental follow-up confirmed that LY86 knockdown results in reduced monocyte migration towards the chemokine MCP-1, thereby implying that this reduced migration may underlie the increased susceptibility to candidemia. Altogether, our integrative systems genetics approach identifies previously unknown mechanisms underlying the immune response to Candida infection.


Assuntos
Antígenos de Superfície/genética , Antígenos de Superfície/imunologia , Candida albicans/fisiologia , Candidíase/genética , Candida albicans/imunologia , Candidemia/genética , Candidemia/imunologia , Candidemia/microbiologia , Candidíase/imunologia , Candidíase/microbiologia , Estudos de Coortes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Células Matadoras Naturais , Análise de Sequência de RNA , Análise de Célula Única
19.
Ecotoxicol Environ Saf ; 197: 110625, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32302863

RESUMO

Due to the potential of release and accumulation in the environment, nanoplastics have attracted an increasing attention. In this study, we investigated the effect of exposure to nanopolystyrene (30 nm) in nematode Caenorhabditis elegans after the fungal infection. After Candida albicans infection, exposure to nanopolystyrene (10 and 100 µg/L) for 24-h could cause the more severe toxicity on lifespan and locomotion behavior compared with fungal infection alone. The more severe activation of oxidative stress and suppression of SOD-3:GFP expression and mitochondrial unfolded protein response (mt UPR) were associated with this observed toxicity enhancement induced by nanopolystyrene exposure. Moreover, the more severe C. albicans colony formation and suppression of innate immune response as indicated by the alteration in expression of anti-microbial genes (abf-2, cnc-4, cnc-7, and fipr-22/23) further contributed to the formation of this toxicity enhancement induced by nanopolystyrene exposure. Our results demonstrated that short-term exposure to nanopolystyrene in the range of µg/L potentially enhances the adverse effects of fungal infection on organisms.


Assuntos
Caenorhabditis elegans , Candidíase/induzido quimicamente , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Poliestirenos/toxicidade , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/microbiologia , Proteínas de Caenorhabditis elegans/metabolismo , Candida albicans/crescimento & desenvolvimento , Candidíase/microbiologia , Estresse Oxidativo/efeitos dos fármacos
20.
PLoS One ; 15(3): e0226467, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32203515

RESUMO

The aim of this study was to compare the Candida bromcresol green (BCG) medium with the chromogenic (CHROM) Brilliance Candida agar and Sabouraud dextrose agar (SDA) media in regard to their capability of detecting Candida isolates from mono- or dual-species cultures. We prepared Candida isolates' suspensions to obtain mono-species (n = 18) or dual-species (n = 153) culture plates per each medium, and three readers independently observed 513 plates at 24-h, 48-h and 72-h incubation time. We scored reading results as correct, over or under detection compared to the expected species number(s). BCG showed significantly higher correct-detection and lower under-detection rates for all Candida species when observed by at least one reader. At 24-h reading, 12 mono-species cultures had correct (or over) detections in all media, whereas 106, 60 and 78 dual-species cultures had correct (or over) detections in BCG, CHROM or SDA, respectively. BCG provides the basis for an accurate laboratory diagnosis of Candida infections.


Assuntos
Ágar/química , Candida/isolamento & purificação , Candidíase/diagnóstico , Meios de Cultura/química , Indicadores e Reagentes/química , Candidíase/microbiologia , Humanos , Técnicas Microbiológicas/métodos
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