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1.
Artigo em Inglês | MEDLINE | ID: mdl-31932372

RESUMO

Five Candida krusei isolates (susceptible and resistant) recovered from the urine of a kidney transplant patient treated with voriconazole (VRC) 200 mg twice daily for 20 days were studied. Eight unrelated clinical isolates of C. krusei were exposed in vitro to VRC 0.001 µg/ml for 30 days. Development of VRC transient resistance occurred in vivo, and induction of permanent resistance occurred in vitro Mostly, ABC1 and ERG11 genes were overexpressed, and a homozygous T418C mutation in the ERG11 gene was found.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Antifúngicos/farmacologia , Farmacorresistência Fúngica/genética , Micoses/tratamento farmacológico , Pichia/efeitos dos fármacos , Voriconazol/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Sistema Enzimático do Citocromo P-450/genética , Feminino , Humanos , Transplante de Rim/efeitos adversos , Testes de Sensibilidade Microbiana , Micoses/microbiologia , Pichia/genética , Pichia/isolamento & purificação , Adulto Jovem
2.
Artigo em Inglês | MEDLINE | ID: mdl-30348666

RESUMO

Candida glabrata is an emerging fungal pathogen. Its increased prevalence is associated with its ability to rapidly develop antifungal drug resistance, particularly to azoles. In order to unravel new molecular mechanisms behind azole resistance, a transcriptomics analysis of the evolution of a C. glabrata clinical isolate (isolate 044) from azole susceptibility to posaconazole resistance (21st day), clotrimazole resistance (31st day), and fluconazole and voriconazole resistance (45th day), induced by longstanding incubation with fluconazole, was carried out. All the evolved strains were found to accumulate lower concentrations of azole drugs than the parental strain, while the ergosterol concentration remained mostly constant. However, only the population displaying resistance to all azoles was found to have a gain-of-function mutation in the C. glabrataPDR1 gene, leading to the upregulation of genes encoding multidrug resistance transporters. Intermediate strains, exhibiting posaconazole/clotrimazole resistance and increased fluconazole/voriconazole MIC levels, were found to display alternative ways to resist azole drugs. Particularly, posaconazole/clotrimazole resistance after 31 days was correlated with increased expression of adhesin genes. This finding led us to identify the Epa3 adhesin as a new determinant of azole resistance. Besides being required for biofilm formation, Epa3 expression was found to decrease the intracellular accumulation of azole antifungal drugs. Altogether, this work provides a glimpse of the transcriptomics evolution of a C. glabrata population toward multiazole resistance, highlighting the multifactorial nature of the acquisition of azole resistance and pointing out a new player in azole resistance.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Farmacorresistência Fúngica/genética , Candida glabrata/isolamento & purificação , Clotrimazol/farmacologia , Ergosterol/metabolismo , Fluconazol/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana Transportadoras/genética , Testes de Sensibilidade Microbiana , Fatores de Transcrição/genética , Transcriptoma/genética , Triazóis/farmacologia , Voriconazol/farmacologia
3.
Mycoses ; 62(12): 1194-1201, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31556177

RESUMO

BACKGROUND: Biofilm formation represents a major microbial virulence attribute especially at epithelial surfaces such as the skin. Malassezia biofilm formation at the skin surface has not yet been addressed. OBJECTIVE: The present study aimed to evaluate Malassezia colonisation pattern on a reconstructed human epidermis (RhE) by imaging techniques. METHODS: Malassezia clinical isolates were previously isolated from volunteers with pityriasis versicolor and seborrhoeic dermatitis. Yeast of two strains of M furfur and M sympodialis were inoculated onto the SkinEthic™ RHE. The tissues were processed for light microscopy, wide-field fluorescence microscopy and scanning electron microscopy. RESULTS: Colonisation of the RhE surface with aggregates of Malassezia yeast entrapped in a multilayer sheet with variable amount of extracellular matrix was unveiled by imaging techniques following 24, 48, 72 and 96 hours of incubation. Whenever yeast were suspended in RPMI medium supplemented with lipids, the biofilm substantially increased with a dense extracellular matrix in which the yeast cells were embedded. Slight differences were found in the biofilm architectural structure between the two tested species with an apparently higher entrapment and viscosity in M furfur biofilm. CONCLUSION: Skin isolates of M furfur and M sympodialis were capable of forming biofilm in vitro at the epidermal surface simulating in vivo conditions. Following 24 hours of incubation, without added lipids, rudimental matrix was barely visible, conversely to the reported at plastic surfaces. The amount of biofilm apparently increased progressively from 48 to 96 hours. A structural heterogeneity of biofilm between species was found.


Assuntos
Biofilmes , Epiderme/microbiologia , Processamento de Imagem Assistida por Computador , Malassezia/isolamento & purificação , Pele Artificial/microbiologia , Dermatite Seborreica/microbiologia , Humanos , Malassezia/ultraestrutura , Microscopia Eletrônica de Varredura , Tinha Versicolor/microbiologia
4.
Antimicrob Agents Chemother ; 60(6): 3824-6, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27021318

RESUMO

A flow cytometry test was developed to identify carbapenemase production by Enterobacteriaceae and to discriminate between the different types of carbapenemases (classes A, B, and D). It is based on the detection of meropenem activity against bacteria, coupled with different carbapenemase inhibitors, which is assessed by flow cytometry. It represents a convenient, fast, and reliable approach (100% sensitivity and 100% specificity) for the detection and characterization of different carbapenemases.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/classificação , Enterobacteriaceae/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo/métodos , Tienamicinas/farmacologia , beta-Lactamases/classificação , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ácidos Borônicos/farmacologia , Cloxacilina/farmacologia , Ácido Edético/farmacologia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Enterobacteriaceae/crescimento & desenvolvimento , Infecções por Enterobacteriaceae/microbiologia , Expressão Gênica , Humanos , Meropeném , Penicilinas/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
5.
Yeast ; 33(10): 523-533, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27279567

RESUMO

Debaryomyces hansenii is a halotolerant yeast with a high biotechnological potential, particularly in the food industry. However, research in this yeast is limited by its molecular peculiarities. In this review we summarize the state of the art of research in this microorganisms, describing both pros and cons. We discuss (i) its halotolerance, (ii) the molecular factors involved in saline and osmotic stress, (iii) its high gene density and ambiguous CUG decoding, and (iv) its biotechnological and medical interests. We trust that all the bottlenecks in its study will soon be overcome and D. hansenii will become a fundamental organism for food biotechnological processes. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Biotecnologia , Debaryomyces/fisiologia , Tecnologia de Alimentos/tendências , Biotecnologia/tendências , Cátions/metabolismo , Debaryomyces/genética , Genoma Fúngico/genética , Halogênios/metabolismo , Pressão Osmótica/fisiologia
6.
Antimicrob Agents Chemother ; 59(10): 6629-33, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26248365

RESUMO

Candida parapsilosis is the second most prevalent fungal agent causing bloodstream infections. Nevertheless, there is little information about the molecular mechanisms underlying azole resistance in this species. Mutations (G1747A, A2619C, and A3191C) in the MRR1 transcription factor gene were identified in fluconazole- and voriconazole-resistant strains. Independent expression of MRR1 genes harboring these mutations showed that G1747A (G583R) and A2619C (K873N) are gain-of-function mutations responsible for azole resistance, the first described in C. parapsilosis.


Assuntos
Fluconazol/farmacologia , Proteínas Fúngicas/genética , Fatores de Transcrição/genética , Voriconazol/farmacologia , Candida/efeitos dos fármacos , Candida/genética , Farmacorresistência Fúngica , Proteínas Fúngicas/fisiologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Dados de Sequência Molecular , Mutação/genética , Fatores de Transcrição/fisiologia
7.
Antimicrob Agents Chemother ; 59(7): 4289-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25845879

RESUMO

Candida albicans is the most prevalent cause of fungemia worldwide. Its ability to develop resistance in patients receiving azole antifungal therapy is well documented. In a murine model of systemic infection, we show that ibuprofen potentiates fluconazole antifungal activity against a fluconazole-resistant strain, drastically reducing the fungal burden and morbidity. The therapeutic combination of fluconazole with ibuprofen may constitute a new approach for the management of antifungal therapeutics to reverse the resistance conferred by efflux pump overexpression.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Fluconazol/uso terapêutico , Ibuprofeno/uso terapêutico , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candidíase/microbiologia , Farmacorresistência Fúngica/genética , Sinergismo Farmacológico , Feminino , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana
8.
J Antimicrob Chemother ; 70(4): 1083-93, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25558078

RESUMO

OBJECTIVES: The objective of this study was to clarify the antifungal properties of cerium, a lanthanide member, against Candida species. A comprehensive study with planktonic and sessile cells was performed. The ability of cerium nitrate (CN) to impair in vitro and in vivo biofilm formation was evaluated and its potential use in biofilm treatment was also evaluated. METHODS: Forty-eight clinical isolates of different Candida species and the type strain ATCC 90028 were tested according to the protocol M27-A3. The MICs and minimum lethal concentrations were determined. A time-kill assay was performed and a cytometric kinetic study was performed using live/dead markers. Biofilm inhibition and biofilm susceptibility in the presence of cerium was evaluated by quantification of the biofilm metabolic activity and total biomass with XTT and crystal violet assays, respectively. CN in vivo efficacy as a coating for medical indwelling devices was evaluated for the first time for Candida parapsilosis, using a mouse subcutaneous foreign body model using polyurethane catheter segments. Scanning electron microscopy was used to assess biofilm architecture after CN treatment. RESULTS: The MICs for planktonic cells correlated with severe cellular metabolic activity impairment and membrane damage after 3 h of incubation. Moreover, CN efficiently prevented biofilm formation both in vitro and in vivo in segments of polyurethane catheters. At higher concentrations, it was also able to disorganize and almost eradicate preformed biofilms. CONCLUSIONS: Our results strongly suggest that CN application in the clinical setting might be effective in preventing the formation of biofilm-associated infections, namely through catheter coating and ultimately as an antimicrobial lock therapy.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Candida/fisiologia , Cério/farmacologia , Animais , Candida/isolamento & purificação , Candidíase/microbiologia , Catéteres/microbiologia , Feminino , Corpos Estranhos/microbiologia , Violeta Genciana/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Coloração e Rotulagem , Sais de Tetrazólio/metabolismo
9.
Antimicrob Agents Chemother ; 58(8): 4604-11, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24867987

RESUMO

Candida krusei is an important agent of opportunistic infections that often displays resistance to several antifungals. We describe here the in vivo acquisition of resistance to voriconazole (VRC) by C. krusei isolates recovered from a leukemia patient during a long period of VRC therapy. In order to mimic the in vivo development of VRC resistance, a susceptible C. krusei isolate was exposed daily to 1 µg/ml of VRC in vitro. Interestingly, after 5 days of exposure to VRC, a MIC of 4 µg/ml was achieved; this value remained constant after 25 additional days of treatment with VRC and also after 30 consecutive days of incubation in VRC-free medium. Our objective was to determine the associated molecular resistance mechanisms, such as expression of efflux pump genes and ERG11 gene mutations, among the resistant strains. Synergistic effects between the efflux blocker tacrolimus (FK506) and VRC were found in all of the resistant strains. Moreover, ABC1 gene expression increased over time in both the in vivo- and in vitro-induced resistant strains, in contrast to the ABC2 and ERG11 genes, whose expression was invariably lower and constant. ERG11 gene sequencing showed two different types of mutations, i.e., heterozygosity at T1389T/C, corresponding to synonymous mutations, in C. krusei strains and a missense mutation at position T418C, resulting in a change from Tyr to His, among resistant C. krusei clinical isolates. This study highlights the relevance of ATP-dependent efflux pump (namely, Abc1p) activity in VRC resistance and describes new mutations in the ERG11 gene among resistant C. krusei clinical isolates.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Candida/efeitos dos fármacos , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Esterol 14-Desmetilase/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adulto , Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Candida/genética , Candida/metabolismo , Candidíase/complicações , Candidíase/tratamento farmacológico , Candidíase/microbiologia , Candidíase/patologia , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Proteínas Fúngicas/metabolismo , Expressão Gênica , Humanos , Masculino , Mutação , Infecções Oportunistas/complicações , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/microbiologia , Infecções Oportunistas/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/microbiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Esterol 14-Desmetilase/metabolismo , Tacrolimo/farmacologia , Voriconazol/farmacologia
10.
BMC Microbiol ; 14: 155, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24920078

RESUMO

BACKGROUND: The purpose of this study was to unveil whether azole antifungals used in agriculture, similar to the clinical azoles used in humans, can evoke resistance among relevant human pathogens like Aspergillus fumigatus, an ubiquitous agent in nature. Additionally, cross-resistance with clinical azoles was investigated. Antifungal susceptibility testing of environmental and clinical isolates of A. fumigatus was performed according to the CLSI M38-A2 protocol. In vitro induction assays were conducted involving daily incubation of susceptible A. fumigatus isolates, at 35°C and 180 rpm, in fresh GYEP broth medium supplemented with Prochloraz (PCZ), a potent agricultural antifungal, for a period of 30 days. Minimal inhibitory concentrations (MIC) of PCZ and clinical azoles were monitored every ten days. In order to assess the stability of the developed MIC, the strains were afterwards sub-cultured for an additional 30 days in the absence of antifungal. Along the in vitro induction process, microscopic and macroscopic cultural observations were registered. RESULTS: MIC of PCZ increased 256 times after the initial exposure; cross-resistance to all tested clinical azoles was observed. The new MIC value of agricultural and of clinical azoles maintained stable in the absence of the selective PCZ pressure. PCZ exposure was also associated to morphological colony changes: macroscopically the colonies became mostly white, losing the typical pigmentation; microscopic examination revealed the absence of conidiation. CONCLUSIONS: PCZ exposure induced Aspergillus fumigatus morphological changes and an evident increase of MIC value to PCZ as well as the development of cross-resistance with posaconazole, itraconazole and voriconazole.


Assuntos
Aspergillus fumigatus/efeitos dos fármacos , Azóis/farmacologia , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Imidazóis/farmacologia , Aspergilose/microbiologia , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/isolamento & purificação , Meios de Cultura/química , Microbiologia Ambiental , Humanos , Testes de Sensibilidade Microbiana , Mutação , Inoculações Seriadas , Temperatura
11.
FEMS Yeast Res ; 14(7): 1119-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25132632

RESUMO

Acquisition of azole resistance by clinically relevant yeasts in nature may result in a significant, yet undetermined, impact in human health. The main goal of this study was to assess the development of cross-resistance between agricultural and clinical azoles by Candida spp. An in vitro induction assay was performed, for a period of 90 days, with prochloraz (PCZ) - an agricultural antifungal. Afterward, the induced molecular resistance mechanisms were unveiled. MIC value of PCZ increased significantly in all Candida spp. isolates. However, only C. glabrata developed cross-resistance to fluconazole and posaconazole. The increased MIC values were stable. Candida glabrata azole resistance acquisition triggered by PCZ exposure involved the upregulation of the ATP binding cassette multidrug transporter genes and the transcription factor, PDR1. Single mutation previously implicated in azole resistance was found in PDR1 while ERG11 showed several synonymous single nucleotide polymorphisms. These results might explain why C. glabrata is so commonly less susceptible to clinical azoles, suggesting that its exposure to agricultural azole antifungals may be associated to the emergence of cross-resistance. Such studies forward potential explanations for the worldwide increasing clinical prevalence of C. glabrata and the associated worse prognosis of an infection by this species.


Assuntos
Antifúngicos/farmacologia , Candida glabrata/efeitos dos fármacos , Farmacorresistência Fúngica , Fungicidas Industriais/farmacologia , Imidazóis/farmacologia , Triazóis/farmacologia , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
J Fungi (Basel) ; 10(5)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38786691

RESUMO

Candida auris, a multidrug-resistant yeast, poses significant challenges in healthcare settings worldwide. Understanding its environmental reservoirs is crucial for effective control strategies. This systematic review aimed to review the literature regarding the natural and environmental reservoirs of C. auris. Following the PRISMA guidelines, published studies until October 2023 were searched in three databases: PubMed, Web of Science, and Scopus. Information regarding the origin, sampling procedure, methods for laboratory identification, and antifungal susceptibility was collected and analyzed. Thirty-three studies published between 2016 and 2023 in 15 countries were included and analyzed. C. auris was detected in various environments, including wastewater treatment plants, hospital patient care surfaces, and natural environments such as salt marshes, sand, seawater, estuaries, apples, and dogs. Detection methods varied, with molecular techniques often used alongside culture. Susceptibility profiles revealed resistance patterns. Phylogenetic studies highlight the potential of environmental strains to influence clinical infections. Despite methodological heterogeneity, this review provides valuable information for future research and highlights the need for standardized sampling and detection protocols to mitigate C. auris transmission.

13.
Biomolecules ; 14(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38927134

RESUMO

A notable shift in understanding the human microbiome's influence on cardiovascular disease (CVD) is underway, although the causal association remains elusive. A systematic review and meta-analysis were conducted to synthesise current knowledge on microbial taxonomy and metabolite variations between healthy controls (HCs) and those with CVD. An extensive search encompassing three databases identified 67 relevant studies (2012-2023) covering CVD pathologies from 4707 reports. Metagenomic and metabolomic data, both qualitative and quantitative, were obtained. Analysis revealed substantial variability in microbial alpha and beta diversities. Moreover, specific changes in bacterial populations were shown, including increased Streptococcus and Proteobacteria and decreased Faecalibacterium in patients with CVD compared with HC. Additionally, elevated trimethylamine N-oxide levels were reported in CVD cases. Biochemical parameter analysis indicated increased fasting glucose and triglycerides and decreased total cholesterol and low- and high-density lipoprotein cholesterol levels in diseased individuals. This study revealed a significant relationship between certain bacterial species and CVD. Additionally, it has become clear that there are substantial inconsistencies in the methodologies employed and the reporting standards adhered to in various studies. Undoubtedly, standardising research methodologies and developing extensive guidelines for microbiome studies are crucial for advancing the field.


Assuntos
Doenças Cardiovasculares , Microbioma Gastrointestinal , Humanos , Doenças Cardiovasculares/microbiologia , Doenças Cardiovasculares/metabolismo , Bactérias/metabolismo , Bactérias/classificação , Bactérias/genética , Metilaminas/metabolismo , Metilaminas/sangue
14.
Cytometry A ; 83(3): 324-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23359335

RESUMO

The conventional methods used to evaluate chitin content in fungi, such as biochemical assessment of glucosamine release after acid hydrolysis or epifluorescence microscopy, are low throughput, laborious, time-consuming, and cannot evaluate a large number of cells. We developed a flow cytometric assay, efficient, and fast, based on Calcofluor White staining to measure chitin content in yeast cells. A staining index was defined, its value was directly related to chitin amount and taking into consideration the different levels of autofluorecence. Twenty-two Candida spp. and four Cryptococcus neoformans clinical isolates with distinct susceptibility profiles to caspofungin were evaluated. Candida albicans clinical isolate SC5314, and isogenic strains with deletions in chitin synthase 3 (chs3Δ/chs3Δ) and genes encoding predicted GlycosylPhosphatidylInositol (GPI)-anchored proteins (pga31Δ/Δ and pga62Δ/Δ), were used as controls. As expected, the wild-type strain displayed a significant higher chitin content (P < 0.001) than chs3Δ/chs3Δ and pga31Δ/Δ especially in the presence of caspofungin. Ca. parapsilosis, Ca. tropicalis, and Ca. albicans showed higher cell wall chitin content. Although no relationship between chitin content and antifungal drug susceptibility phenotype was found, an association was established between the paradoxical growth effect in the presence of high caspofungin concentrations and the chitin content. This novel flow cytometry protocol revealed to be a simple and reliable assay to estimate cell wall chitin content of fungi.


Assuntos
Candida/química , Parede Celular/química , Quitina/análise , Cryptococcus neoformans/química , Citometria de Fluxo/métodos , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/genética , Candida/ultraestrutura , Caspofungina , Quitina Sintase/genética , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/ultraestrutura , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Fluorescência , Proteínas Fúngicas/genética , Proteínas Ligadas por GPI/genética , Glicosilfosfatidilinositóis/análise , Lipopeptídeos , Deleção de Sequência , Coloração e Rotulagem
15.
J Fungi (Basel) ; 9(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36675901

RESUMO

Candida parapsilosis is the second most common Candida species isolated in Asia, Southern Europe, and Latin America and is often involved in invasive infections that seriously impact human health. This pathogen is part of the psilosis complex, which also includes Candida orthopsilosis and Candida metapsilosis. C. parapsilosis infections are particularly prevalent among neonates with low birth weights, individuals who are immunocompromised, and patients who require prolonged use of a central venous catheter or other indwelling devices, whose surfaces C. parapsilosis exhibits an enhanced capacity to adhere to and form biofilms. Despite this well-acknowledged prevalence, the biology of C. parapsilosis has not been as extensively explored as that of Candida albicans. In this paper, we describe the molecular mechanistic pathways of virulence in C. parapsilosis and show how they differ from those of C. albicans. We also describe the mode of action of antifungal drugs used for the treatment of Candida infections, namely, polyenes, echinocandins, and azoles, as well as the resistance mechanisms developed by C. parapsilosis to overcome them. Finally, we stress the importance of the ongoing search for species-specific features that may aid the development of effective control strategies and thus reduce the burden on patients and healthcare costs.

16.
Microorganisms ; 11(7)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37512921

RESUMO

Gestational diabetes, affecting about 10% of pregnancies, is characterized by impaired glucose regulation and can lead to complications for health of pregnant women and their offspring. The microbiota, the resident microbes within the body, have been linked to the development of several metabolic conditions. This systematic review with meta-analysis aims to summarize the evidence on the differences in microbiota composition in pregnant women with gestational diabetes and their offspring compared to healthy pregnancies. A thorough search was conducted in the PubMed, Scopus, and Web of Science databases, and data from 21 studies were analyzed utilizing 41 meta-analyses. In the gut microbiota, Bifidobacterium and Alistipes were found to be more abundant in healthy pregnancies, while Roseburia appears to be more abundant in gestational diabetes. The heterogeneity among study findings regarding the microbiota in the meconium is considerable. The placental microbiota exhibited almost no heterogeneity, with an increased abundance of Firmicutes in the gestational diabetes group and a higher abundance of Proteobacteria in the control. The role of the microbiota in gestational diabetes is reinforced by these findings, which additionally point to the potential of microbiome-targeted therapies. To completely comprehend the interactions between gestational diabetes and the microbiome, standardizing methodologies and further research is necessary.

17.
Cancers (Basel) ; 15(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36900215

RESUMO

Prostate cancer (PCa) is the most common malignant neoplasm with the highest worldwide incidence in men aged 50 years and older. Emerging evidence suggests that the microbial dysbiosis may promote chronic inflammation linked to the development of PCa. Therefore, this study aims to compare the microbiota composition and diversity in urine, glans swabs, and prostate biopsies between men with PCa and non-PCa men. Microbial communities profiling was assessed through 16S rRNA sequencing. The results indicated that α-diversity (number and abundance of genera) was lower in prostate and glans, and higher in urine from patients with PCa, compared to non-PCa patients. The different genera of the bacterial community found in urine was significantly different in PCa patients compared to non-PCa patients, but they did not differ in glans and prostate. Moreover, comparing the bacterial communities present in the three different samples, urine and glans show a similar genus composition. Linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed significantly higher levels of the genera Streptococcus, Prevotella, Peptoniphilus, Negativicoccus, Actinomyces, Propionimicrobium, and Facklamia in urine of PCa patients, whereas Methylobacterium/Methylorubrum, Faecalibacterium, and Blautia were more abundant in the non-PCa patients. In glans, the genus Stenotrophomonas was enriched in PCa subjects, while Peptococcus was more abundant in non-PCa subjects. In prostate, Alishewanella, Paracoccus, Klebsiella, and Rothia were the overrepresented genera in the PCa group, while Actinomyces, Parabacteroides, Muribaculaceae sp., and Prevotella were overrepresented in the non-PCa group. These findings provide a strong background for the development of potential biomarkers with clinical interest.

18.
Thyroid ; 33(8): 983-996, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37140469

RESUMO

Background: Low levels of triiodothyronine (T3) are common in patients with heart failure (HF). Our aim was to evaluate the effects of supplementation with low and replacement doses of T3 in an animal model of HF with preserved ejection fraction (HFpEF). Methods: We evaluated four groups: ZSF1 Lean (n = 8, Lean-Ctrl), ZSF1 Obese (rat model of metabolic-induced HFpEF, n = 13, HFpEF), ZSF1 Obese treated with a replacement dose of T3 (n = 8, HFpEF-T3high), and ZSF1 Obese treated with a low-dose of T3 (n = 8, HFpEF-T3low). T3 was administered in drinking water from weeks 13 to 24. The animals underwent anthropometric and metabolic assessments, echocardiography, and peak effort testing with maximum O2 consumption (VO2max) determination at 22 weeks, and a terminal hemodynamic evaluation at 24 weeks. Afterwhile myocardial samples were collected for single cardiomyocyte evaluation and molecular studies. Results: HFpEF animals showed lower serum and myocardial thyroid hormone levels than Lean-Ctrl. Treatment with T3 did not normalize serum T3 levels, but increased myocardial T3 levels to normal levels in the HFpEF-T3high group. Body weight was significantly decreased in both the T3-treated groups, comparing with HFpEF. An improvement in glucose metabolism was observed only in HFpEF-T3high. Both the treated groups had improved diastolic and systolic function in vivo, as well as improved Ca2+ transients and sarcomere shortening and relaxation in vitro. Comparing with HFpEF animals, HFpEF-T3high had increased heart rate and a higher rate of premature ventricular contractions. Animals treated with T3 had higher myocardial expression of calcium transporter ryanodine receptor 2 (RYR2) and α-myosin heavy chain (MHC), with a lower expression of ß-MHC. VO2max was not influenced by treatment with T3. Myocardial fibrosis was reduced in both the treated groups. Three animals died in the HFpEF-T3high group. Conclusions: Treatment with T3 was shown to improve metabolic profile, myocardial calcium handling, and cardiac function. While the low dose was well-tolerated and safe, the replacement dose was associated with increased heart rate, and increased risk of arrhythmias and sudden death. Modulation of thyroid hormones may be a potential therapeutic target in HFpEF; however, it is important to take into account the narrow therapeutic window of T3 in this condition.


Assuntos
Insuficiência Cardíaca , Ratos , Animais , Insuficiência Cardíaca/tratamento farmacológico , Volume Sistólico , Tri-Iodotironina/farmacologia , Tri-Iodotironina/uso terapêutico , Cálcio/metabolismo , Modelos Animais de Doenças , Obesidade/complicações
19.
Clin Microbiol Infect ; 28(12): 1655.e5-1655.e8, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36028086

RESUMO

OBJECTIVES: Hereby, we describe the molecular mechanisms underlying the acquisition of azole resistance by a Candida parapsilosis isolate following fluconazole treatment due to candiduria. METHODS: A set of three consecutive C. parapsilosis isolates were recovered from the urine samples of a patient with candiduria. Whole-genome sequencing and antifungal susceptibility assays were performed. The expression of MRR1, MDR1, ERG11 and CDR1B (CPAR2_304370) was quantified by RT-qPCR. RESULTS: The initial isolate CPS-A was susceptible to all three azoles tested (fluconazole, voriconazole and posaconazole); isolate CPS-B, collected after the second cycle of treatment, exhibited a susceptible-dose-dependent phenotype to fluconazole and isolate CPS-C, recovered after the third cycle, exhibited a cross-resistance profile to fluconazole and voriconazole. Whole-genome sequencing revealed a putative resistance mechanism in isolate CPS-C, associated with a G1810A nucleotide substitution, leading to a G604R change in the Mrr1p transcription factor. Introducing this mutation into the susceptible CPS-A isolate (MRR1RI) resulted in resistance to fluconazole and voriconazole, as well as up-regulation of MRR1 and MDR1. Interestingly, the susceptible-dose-dependent phenotype exhibited by isolate CPS-B was associated with an increased copy number of the CDR1B gene. The expression of CDR1B was increased in both isolates CPS-B and CPS-C and in the MRR1RI strain, harbouring the gain-of-function mutation. CONCLUSIONS: Our results describe clinical azole cross-resistance acquisition in C. parapsilosis due to a G1810A (G604R) gain-of-function mutation, resulting in MRR1 hyperactivation and consequently, MDR1 efflux pump overexpression. We also associated amplification of the CDR1B gene with decreased fluconazole susceptibility and showed that it is a putative target of the MRR1 gain-of-function mutation.


Assuntos
Candida parapsilosis , Candidíase , Candida parapsilosis/genética , Azóis/farmacologia , Azóis/uso terapêutico , Fluconazol/farmacologia , Fluconazol/uso terapêutico , Voriconazol/farmacologia , Voriconazol/uso terapêutico , Farmacorresistência Fúngica/genética , Mutação com Ganho de Função , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candidíase/tratamento farmacológico , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Mutação
20.
Commun Biol ; 5(1): 1118, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36271293

RESUMO

The increasing prevalence of candidosis caused by Candida glabrata is related to its ability to acquire azole resistance. Although azole resistance mechanisms are well known, the mechanisms for azole import into fungal cells have remained obscure. In this work, we have characterized two hexose transporters in C. glabrata and further investigate their role as potential azole importers. Three azole susceptible C. glabrata clinical isolates were evolved towards azole resistance and the acquired resistance phenotype was found to be independent of CgPDR1 or CgERG11 mutations. Through whole-genome sequencing, CgHXT4/6/7 was found to be mutated in the three evolved strains, when compared to their susceptible parents. CgHxt4/6/7 and the 96% identical CgHxt6/7 were found to confer azole susceptibility and increase azole accumulation in C. glabrata cells, strikingly rescuing the susceptibility phenotype imposed by CgPDR1 deletion, while the identified loss-of-function mutation in CgHXT4/6/7, leads to increased azole resistance. In silico docking analysis shows that azoles display a strong predicted affinity for the glucose binding site of CgHxt4/6/7. Altogether, we hypothesize that hexose transporters, such as CgHxt4/6/7 and CgHxt6/7, may constitute a family of azole importers, involved in clinical drug resistance in fungal pathogens, and constituting promising targets for improved antifungal therapy.


Assuntos
Azóis , Candida glabrata , Candida glabrata/genética , Azóis/farmacologia , Azóis/uso terapêutico , Farmacorresistência Fúngica/genética , Antifúngicos/farmacologia , Glucose , Evolução Molecular , Hexoses
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