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Fungicidal effect of photodynamic therapy against fluconazole-resistant Candida albicans and Candida glabrata

DOVIGO, Livia Nordi; PAVARINA, Ana Claudia; MIMA, Ewerton Garcia de Oliveira; GIAMPAOLO, Eunice Teresinha; VERGANI, Carlos Eduardo; BAGNATO, Vanderlei Salvador
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
66.87%
P>Although photodynamic therapy (PDT) has shown great promise for the inactivation of Candida species, its effectiveness against azole-resistant pathogens remains poorly documented. This in vitro study describes the association of Photogem (R) (Photogem, Moscow, Russia) with LED (light emitting diode) light for the photoinactivation of fluconazole-resistant (FR) and American Type Culture Collection (ATCC) strains of Candida albicans and Candida glabrata. Suspensions of each Candida strain were treated with five Photogem (R) concentrations and exposed to four LED light fluences (14, 24, 34 or 50 min of illumination). After incubation (48 h at 37 degrees C), colonies were counted (CFU ml-1). Single-species biofilms were generated on cellulose membrane filters, treated with 25.0 mg l-1 of Photogem (R) and illuminated at 37.5 J cm-2. The biofilms were then disrupted and the viable yeast cells present were determined. Planktonic suspensions of FR strains were effectively killed after PDT. It was observed that the fungicidal effect of PDT was strain-dependent. Significant decreases in biofilm viability were observed for three strains of C. albicans and for two strains of C. glabrata. The results of this investigation demonstrated that although PDT was effective against Candida species...

Silver colloidal nanoparticles: antifungal effect against adhered cells and biofilms of Candida albicans and Candida glabrata

Monteiro, D. R.; Gorup, L. F.; Silva, S.; Negri, M.; de Camargo, E. R.; Oliveira, R.; Barbosa, D. B.; Henriques, M.
Fonte: Taylor & Francis Ltd Publicador: Taylor & Francis Ltd
Tipo: Artigo de Revista Científica Formato: 711-719
Português
Relevância na Pesquisa
66.92%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applied to adhered cells (2 h) or biofilms (48 h) and after 24 h of contact their effect was assessed by enumeration of colony forming units (CFUs) and quantification of total biomass (by crystal violet staining). The MIC results showed that SN were fungicidal against all strains tested at very low concentrations (0.4-3.3 mu g ml(-1)). Furthermore, SN were more effective in reducing biofilm biomass when applied to adhered cells (2 h) than to pre-formed biofilms (48 h), with the exception of C. glabrata ATCC, which in both cases showed a reduction similar to 90%. Regarding cell viability, SN were highly effective on adhered C. glabrata and respective biofilms. on C. albicans the effect was not so evident but there was also a reduction in the number of viable biofilm cells. In summary...

Fungicidal effect of photodynamic therapy against fluconazole-resistant Candida albicans and Candida glabrata

Dovigo, Livia Nordi; Pavarina, Ana Claudia; de Oliveira Mima, Ewerton Garcia; Giampaolo, Eunice Teresinha; Vergani, Carlos Eduardo; Bagnato, Vanderlei Salvador
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 123-130
Português
Relevância na Pesquisa
66.87%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 05/03226-3; Processo FAPESP: 05/02193-4; Although photodynamic therapy (PDT) has shown great promise for the inactivation of Candida species, its effectiveness against azole-resistant pathogens remains poorly documented. This in vitro study describes the association of Photogem (R) (Photogem, Moscow, Russia) with LED (light emitting diode) light for the photoinactivation of fluconazole-resistant (FR) and American Type Culture Collection (ATCC) strains of Candida albicans and Candida glabrata. Suspensions of each Candida strain were treated with five Photogem (R) concentrations and exposed to four LED light fluences (14, 24, 34 or 50 min of illumination). After incubation (48 h at 37 degrees C), colonies were counted (CFU ml-1). Single-species biofilms were generated on cellulose membrane filters, treated with 25.0 mg l-1 of Photogem (R) and illuminated at 37.5 J cm-2. The biofilms were then disrupted and the viable yeast cells present were determined. Planktonic suspensions of FR strains were effectively killed after PDT. It was observed that the fungicidal effect of PDT was strain-dependent. Significant decreases in biofilm viability were observed for three strains of C. albicans and for two strains of C. glabrata. The results of this investigation demonstrated that although PDT was effective against Candida species...

The effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic

Silva, Sónia; Pires, Priscila; Monteiro, Douglas R.; Negri, Melyssa; Gorup, Luiz F.; Camargo, Emerson R.; Barbosa, Débora B.; Oliveira, Rosário; Williams, David W.; Henriques, Mariana; Azeredo, Joana
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 178-184
Português
Relevância na Pesquisa
66.98%
The aim of this study was to compare biofi lm formation by Candida glabrata and Candida albicans on acrylic, either individually or when combined (single and dual species) and then examine the antimicrobial effects of silver nanoparticles and nystatin on these biofi lms. Candidal adhesion and biofi lm assays were performed on acrylic surface in the presence of artifi cial saliva (AS) for 2 h and 48 h, respectively. Candida glabrata and C. albicans adherence was determined by the number of colony forming units (CFUs) recovered from the biofi lms on CHROMagar ® Candida . In addition, crystal violet (CV) staining was used as an indicator of biofi lm biomass and to quantify biofi lm formation ability. Pre-formed biofi lms were treated either with silver nanoparticles or nystatin and the effect of these agents on the biofi lms was evaluated after 24 h. Results showed that both species adhered to and formed biofi lms on acrylic surfaces. A signifi cantly ( P < 0.05) higher number of CFUs was evident in C. glabrata biofi lms compared with those formed by C. albicans . Comparing single and dual species biofi lms, equivalent CFU numbers were evident for the individual species. Both silver nanoparticles and nystatin reduced biofi lm biomass and the CFUs of single and dual species biofi lms ( P < 0.05). Silver nanoparticles had a signifi cantly ( P < 0.05) greater effect on reducing C. glabrata biofi lm biomass compared with C. albicans . Similarly...

In vitro adhesion of Candida glabrata to denture base acrylic resin modified by glow-discharge plasma treatment

Zamperini, Camila Andrade; de Lima Carneiro, Haline; Rangel, Elidiane Cipriano; Cruz, Nilson Cristino; Vergani, Carlos Eduardo; Machado, Ana Lucia
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 134-144
Português
Relevância na Pesquisa
66.87%
This study evaluated the potential of plasma treatments to modify the surface chemistry and hydrophobicity of a denture base acrylic resin to reduce the Candida glabrata adhesion. Specimens (n=54) with smooth surfaces were made and divided into three groups (n=18): control - non-treated; experimental groups - submitted to plasma treatment (Ar/50W; AAt/130W). The effects of these treatments on chemical composition and surface topography of the acrylic resin were evaluated. Surface free energy measurements (SFE) were performed after the treatments and after 48h of immersion in water. For each group, half (n=9) of the specimens were preconditionated with saliva before the adhesion assay. The number of adhered C. glabrata was evaluated by cell counting after crystal violet staining. The Ar/50W and AAt/130W treatments altered the chemistry composition, hydrophobicity and topography of acrylic surface. The Ar/50W group showed significantly lower C. glabrata adherence than the control group, in the absence of saliva. After preconditioning with saliva, C. glabrata adherence in experimental and control groups did not differ significantly. There were significant changes in the SFE after immersion in water. The results demonstrated that Ar/50W treated surfaces have potential for reducing C. glabrata adhesion to denture base resins and deserve further investigation...

Microespectroscopia infravermelha por transformada de fourier: identificação e discriminação de cepas clínicas de Candida albicans e Candida glabrata

Cardoso, Michelle
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 76 f. : il.
Português
Relevância na Pesquisa
67.03%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Biopatologia Bucal - ICT; A técnica da espectroscopia infravermelha por transformada de Fourier (FT-IR) vem sendo largamente empregada como uma abordagem rápida e simples para a identificação de microrganismos, incluindo a do gênero Candida. A proposta deste estudo foi avaliar o emprego da microespectroscopia FT-IR na identificação e discriminação de 5 cepas clínicas de Candida albicans e 3 de Candida glabrata, as quais foram identificadas previamente por meio de métodos convencionais, e mais duas cepas ATCC de cada espécie. As amostras foram analisadas em triplicata, a partir de culturas independentes, por meio de filmes finos obtidos da suspensão em solução salina estéril a 0,85% da biomassa da colônia que ficou incubada por 24 horas em placas com ágar Saboraud Dextrose. Dez espectros com 32 varreduras foram obtidos na forma de ponto em 10 regiões selecionadas aleatoriamente nas amostras. A média foi obtida dos dez espectros de cada amostra para a análise estatística multivariada, dada pela análise de cluster. Além disso os espectros foram transformados em primeira derivada e três janelas espectrais foram determinadas (900-1250 cm-1...

In vitro evaluation of adherence of Candida albicans, Candida glabrata, and Streptococcus mutans to an acrylic resin modified by experimental coatings

Izumida, Fernanda Emiko; Moffa, Eduardo Buozi; Vergani, Carlos Eduardo; Machado, Ana Lucia; Jorge, Janaina Habib; Giampaolo, Eunice Teresinha
Fonte: Taylor & Francis Ltd Publicador: Taylor & Francis Ltd
Tipo: Artigo de Revista Científica Formato: 525-533
Português
Relevância na Pesquisa
66.87%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 10/00545-9; Processo FAPESP: 12/01528-6; This study evaluated the effect of experimental coatings, containing zwitterion or hydrophilic monomers, on the adherence of Candida albicans, Candida glabrata, and Streptococcus mutans to an acrylic resin. Acrylic samples (smooth or rough surfaces) were left untreated (control) or coated with one of the following experimental coatings: 3-hydroxypropylmethacrylate (HP) or sulfobetaine methacrylate (S), at concentrations of 25, 30, or 35%. Half of the specimens were coated with saliva. The adhesion test was performed by incubating specimens in C. albicans, C. glabrata, and S. mutans suspensions at 37 degrees C for 90 min. The number of adhered microorganisms was determined by metabolic activity (XTT) and by cell viability (CFU). All coated specimens exhibited lower absorbance and CFU values compared to control specimens. Saliva and roughness did not promote microorganism adherence. An XPS analysis confirmed the modification in the chemical composition of the coatings in the experimental samples. These experimental coatings significantly reduced the adherence of C. albicans, C. glabrata and S. mutans to acrylic resin.

Catabolismo da trealose extracelular e caracterização bioquímica da trealase ácida de Candida glabrata

Zilli, Denise Motta Wanderley
Fonte: Florianópolis, SC Publicador: Florianópolis, SC
Tipo: Dissertação de Mestrado Formato: 94 f.| il., grafs., tabs.
Português
Relevância na Pesquisa
66.91%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas. Programa de Pós-Graduação em Biotecnologia; A levedura Candida glabrata tem sido apontada como importante patógeno emergente, sendo a segunda espécie mais comumente envolvida na etiologia das candidíases, infectando principalmente indivíduos imunodeficientes e imunocomprometidos. Devido à resistencia natural aos antifúngicos azólicos e à alta taxa de mortalidade associada a C. glabrata, os testes rápidos para sua identificação constituem importante ferramenta para a escolha terapêutica. Este microrganismo se destaca da maioria das leveduras por ser capaz de apenas consumir dois açúcares: a glicose e o dissacarídeo trealose (Gli 1-1 Gli). De fato, os testes rápidos de identificação têm como princípio justamente a habilidade desta levedura em hidrolisar as moléculas de trealose em duas de glicose. Dada a importância da metabolização da trealose para C. glabrata, no presente trabalho foi realizada uma caracterização bioquímica do catabolismo de trealose por esta levedura. Nossos resultados mostram que C. glabrata consome e fermenta eficientemente a trealose presente no meio de cultura, com parâmetros cinéticos e produtividades de biomassa e etanol semelhantes aos observados durante a fermentação da glicose. De fato...

Clonagem, expressão heteróloga e obtenção de mutantes da trealase ácida de Candida glabrata

Lopes, Rafael Garcia
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Dissertação de Mestrado Formato: ix, 78 f.| il., grafs., tabs.
Português
Relevância na Pesquisa
66.95%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Programa de Pós-Graduação em Biotecnologia, Florianópolis, 2010; Candida glabrata é considerado um importante patógeno fúngico emergente devido principalmente ao incremento de pacientes imunossuprimidos, e ao uso indiscriminado de compostos azólicos, resultando em altas taxas de mortalidade pela resistência inata desta levedura aos antifúngicos normalmente utilizados. Estratégias que objetivam a pronta identificação deste patógeno são extremamente importantes já que permitem a pronta implementação de um tratamento medicamentoso apropriado. A utilização de trealose por C. glabrata é apontada como importante metodologia diagnóstica na pratica laboratorial, já que é característica marcante desta levedura a utilização de apenas glicose e trealose como fontes de carbono. Resultados prévios indicavam que esta levedura cresce em trealose graças à secreção no meio de cultura de uma trealase ácida que prontamente hidrolisa o dissacarídeo, permitindo a rápida fermentação da glicose liberada. No genoma de C. glabrata encontramos a ORF CAGL0K05137g, similar ao gene (ATH1) que codifica para a trealase ácida de S. cerevisiae. No intuito de verificar a identidade do gene postulado no genoma de C. glabrata como sendo da trealase ácida...

Metabolismo de trealose e caracterização de trealases citoplasmáticas em Candida glabrata

Barros, Ludmila Mascarenhas
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Dissertação de Mestrado Formato: 65 p.| il., grafs.
Português
Relevância na Pesquisa
66.94%
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Bioquímica, Florianópolis, 2011; Candida glabrata é uma levedura encontrada normalmente no trato digestivo humano e mucosas humanas, mas em pacientes imunocomprometidos pode causar infecções sistêmicas de alta morbidade e mortalidade. Esta levedura perdeu vários genes envolvidos no metabolismo de açúcares, sendo capaz de assimilar somente glicose e trealose, uma característica importante no diagnóstico laboratorial deste patógeno emergente. Nosso trabalho se propôs a analisar o metabolismo da trealose, e as enzimas intracelulares (trealase neutra e trealase ácida) envolvidas na degradação deste açúcar. Nossos resultados indicam que embora C. glabrata metabolize a trealose de forma semelhante a outras leveduras (a trealose acumulada na fase estacionária do crescimento é prontamente degradada após suprir as células com glicose), a atividade da trealase neutra nestas células aparentemente não seria responsável pela degradação da trealose uma vez que sua atividade não aumentava no período de maior hidrólise deste açúcar. Nossos resultados também mostram que a alta atividade da trealase ácida presente nas células de C. glabrata...

Silver colloidal nanoparticles : antifungal effect against Candida albicans and Candida glabrata adhered cells and biofilms

Monteiro, D. R.; Gorup, L. F.; Silva, Sónia Carina; Negri, M.; Camargo, E. R.; Oliveira, Rosário; Barbosa, D. B.; Henriques, Mariana
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Artigo de Revista Científica
Publicado em 04/08/2011 Português
Relevância na Pesquisa
66.92%
The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applied to adhered cells (2 h) or biofilms (48 h) and after 24 h of contact their effect was assessed by enumeration of colony forming units (CFUs) and quantification of total biomass (by crystal violet staining). The MIC results showed that SN were fungicidal against all strains tested at very low concentrations (0.4-3.3 μg ml(-1)). Furthermore, SN were more effective in reducing biofilm biomass when applied to adhered cells (2 h) than to pre-formed biofilms (48 h), with the exception of C. glabrata ATCC, which in both cases showed a reduction ∼90%. Regarding cell viability, SN were highly effective on adhered C. glabrata and respective biofilms. On C. albicans the effect was not so evident but there was also a reduction in the number of viable biofilm cells. In summary...

Candida glabrata and Candida albicans co-infection of an in vitro oral epithelium

Silva, Sónia Carina; Henriques, Mariana; Hayes, A.; Oliveira, Rosário; Azeredo, Joana; Williams, D. W.
Fonte: Wiley; Blackwell Publishing Inc. Publicador: Wiley; Blackwell Publishing Inc.
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
67.04%
Candida albicans is regarded as the leading of candidosis. However, Candida glabrata has emerged as an important pathogen of oral mucosa, occurring both singly or in mixed species infections, often with C. albicans. Compared with C. albicans, little is known about the role of C. glabrata in oral infection. The aim of this study was to examine single and mixed species infection of oral epithelium involving C. glabrata and establish its ability to invade and damage tissue. Methods: A reconstituted human oral epithelium (RHOE) was infected only with C. glabrata, or simultaneously with C. glabrata and C. albicans. The ability of both species to invade the tissue was examined using species specific peptide nucleic acid (PNA) probe hybridization and confocal laser scanning microscopy. Epithelial damage was assessed by measuring lactate dehydrogenase (LDH) activity. Results: Candida glabrata strains were able to colonize the RHOE, in a strain dependent manner. Candida glabrata single infection after 12h, generally revealed no invasion of the RHOE, which contrasted with extensive tissue invasion demonstrated by C. albicans. Mixed infection showed that C. albicans enhanced the invasiveness of C. glabrata, and led to increased LDH release by the RHOE...

The role of antifungals agents on Candida glabrata biofilms matrix composition

Silva, Sónia Carina; Lourenço, T.; Negri, M.; Henriques, Mariana; Azeredo, Joana; Oliveira, Rosário
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2010 Português
Relevância na Pesquisa
66.98%
Candida glabrata was considered, for years, a relatively non-pathogenic saprophyte of the normal flora of healthy individuals and as no causative agent of serious infection in humans. However, its high mortality rate and its quick spread confirm the opposite. In fact, due to the widespread and increased use of immunosuppressive therapy together with broad-spectrum antifungal treatments, the frequency of mucosal and systemic infections caused by C. glabrata has increased significantly. Furthermore, biofilms are described as surface associated communities of microorganisms within an extracellular matrix, generally composed of carbohydrate and proteins. Biofilm formation is an important virulence factor for a number of Candida species, as it confers significant resistance to antifungal therapy by limiting the penetration of substances through the matrix and protecting cells from host immune responses. Moreover, little is known about the role of antifungals on C. glabrata biofilms. Thus, the aim of this work was to study the role of fluconazole, itraconazole and amphotericin B on 24 h pre-formed C. glabrata biofilms and specially on their matrix composition. A total of 3 C. glabrata strains isolated from oral, urinary and vaginal tract were used...

Effect of azoles in Candida glabrata biofilms and its relation with ERG genes expression

Rodrigues, Célia; Silva, Sónia Carina; Azeredo, Joana; Gonçalves, Bruna; Henriques, Mariana
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /06/2013 Português
Relevância na Pesquisa
67%
The occurrence of fungal infections has been significantly increasing, thus contributing to higher morbidity and mortality. The use of broad-spectrum antibiotics, catheters, immunosuppression diseases, chemo and radiotherapy are predisposing factors for invasive fungal infection development. Candida albicans is the predominant species in both health and disease conditions, yet, in the last two decades the number of infections due to non-Candida albicans Candida species has increased significantly. Once believed as non-pathogenic, Candida glabrata rapidly was perceived to be responsible for many human diseases. Despite lacking a number of virulence factors allied to the majority of Candida pathogenicity, C. glabrata possesses high ability to colonize medical devices and human epithelium, resulting generally in biofilms formation ability. Its intrinsically low susceptibility to azoles, such as triazoles (e.g. fluconazole (Flu), voriconazole (Vcz)) and its biofilms tolerance is another problem. The aim of this study was to evaluate the effects of Flu (largely used) and Vcz (hospitalenvironment exclusive) in the control of C. glabrata biofilms and its relation with the expression of genes encoding for Ergosterol: ERG3, ERG6 and ERG11. Three isolates of C. glabrata (vaginal...

Candida albicans promotes invasion and colonisation of Candida glabrata in a reconstituted human vaginal epithelium

Alves, Carlos Tiago; Wei, Xiao-Qing; Silva, Sónia Carina; Azeredo, Joana; Henriques, Mariana; Williams, David
Fonte: W. B. Saunders Co., Ltd. Publicador: W. B. Saunders Co., Ltd.
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
66.95%
The principal aim of this study was to investigate the in vitro co-infection of a reconstituted human vaginal epithelium (RHVE) by Candida albicans and Candida glabrata. Methods The ability of both species to invade and colonise the RHVE was examined using species-specific peptide nucleic acid (PNA) probe hybridisation, confocal laser scanning microscopy (CLSM) and a novel qRT-PCR protocol for Candida quantification in the tissues. RHVE damage was evaluated by measuring lactate dehydrogenase (LDH) activity. Candida virulence gene expression (HWP1, ALS, EPA, PLB, PLD and SAP) was evaluated by quantitative RT-PCR. Results The results showed that whilst both species induced damage to the RHVE, this was notably less with C. glabrata. Interestingly, there was a significant increase in C. glabrata RHVE colonisation and invasiveness when it was added to the tissue with C. albicans. The extent of RHVE damage caused by the two species appeared to be primarily dependent on the process of invasion. Of the virulence genes assayed, HWP1, PLD1 and ALS3 were deemed to be most associated with pathogenicity in the model. Conclusions For the first time, we have demonstrated that the RHVE model coupled with specific tools of analysis, allows assessment of Candida colonisation and invasion in single and co-infection. Using this model we have demonstrated that C. albicans enhanced C. glabrata colonisation...

Susceptibility of Candida albicans and Candida glabrata biofilms to silver nanoparticles in intermediate and mature development phases

Monteiro, D. R.; Takamiya, A. S.; Feresin, L. P.; Gorup, L. F.; Camargo, E. R.; Delbem, A. C. B.; Henriques, Mariana; Barbosa, D. B.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2015 Português
Relevância na Pesquisa
66.87%
Purpose: Silver nanoparticles (SN) have been studied as antibiofilm agents, to prevent Candida-associated denture stomatitis. Consequently, the aim of this study was to investigate the influence of the intermediate and maturation stages of Candida albicans and Candida glabrata biofilms development in the susceptibility to SN. Methods: SN (5 nm) suspensions were synthesized via reduction of silver nitrate by a solution of sodium citrate. These suspensions were used to treat, during 5 h, Candida biofilms grown on acrylic surfaces for 24- (intermediate stage) and 48-h (maturation stage), and their efficacy was determined by total biomass (using crystal violet staining) and colony forming units (CFU) quantification. Results: SN promoted significant reductions (p < 0.05) in the total biomass and in the number of CFUs of Candida biofilms ranging from 23-51.5% and 0.96-1.44-log10, respectively. Moreover, there were no significant differences in the total biofilm biomass (p > 0.05), when the different stages of biofilm development (24 or 48 h) were exposed to SN. Comparing the number of CFUs between 24- and 48-h biofilms treated with SN, a significant difference (p < 0.05) was found only for the strain C. albicans 324LA/94. Conclusions: It was concluded that...

Candida glabrata biofilms response to amphotericin B

Rodrigues, Célia F.; Silva, Sónia Carina; Salgado, José Manuel; Abrunhosa, Luís; Venâncio, Armando; Azeredo, Joana; Henriques, Mariana
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em 10/06/2015 Português
Relevância na Pesquisa
66.97%
Background: Candida species are responsible for recurrent human infections, mostly in immunocompromised patients, due to their high vulnerability. Candida glabrata has been showing to have a major role in these infections being the second most prevalent species involved in human fungemia. Amphotericin B (AmB), a common antifungal drug, is a hospital-environment exclusive polyene, normally being efficient when used to fight candidiasis. Objectives: The main goal of this work was to infer about the influence of AmB in Candida glabrata biofilms formation and its effect on matrix composition and ERG genes expression. Methods: Candida glabrata biofilms were formed in the presence of AmB and analyzed by dry weight. Moreover, ERG genes expression was evaluated by qRT-PCR and matrix was analyzed in terms of composition in carbohydrates, proteins, beta-glucans and a new finding: ergosterol. Conclusions: In addition to an inefficient reduction of the C. glabrata biofilms, this work showed that ERG genes seem to be less involved than the matrix composition in C. glabrata biofilms response to AmB. Specifically, C. glabrata biofilms matrices respond with an increase of carbohydrates, particularly beta-1,3 glucans, and with a decrease of total proteins. The ergosterol values did not expressively changed in the presence of AmB. The present work support the theory of multifaceted mechanisms developed by C. glabrata biofilms as response to the presence of AmB.

Oxidative stress response to menadione and cumene hydroperoxide in the opportunistic fungal pathogen Candida glabrata

Cuéllar-Cruz,Mayra; Castaño,Irene; Arroyo-Helguera,Omar; De Las Peñas,Alejandro
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2009 Português
Relevância na Pesquisa
66.92%
Candida glabrata is an opportunistic fungal pathogen that can cause severe invasive infections and can evade phagocytic cell clearance. We are interested in understanding the virulence of this fungal pathogen, in particular its oxidative stress response. Here we investigated C. glabrata, Saccharomyces cerevisiae and Candida albicans responses to two different oxidants: menadione and cumene hydroperoxide (CHP). In log-phase, in the presence of menadione, C. glabrata requires Cta1p (catalase), while in a stationary phase (SP), Cta1p is dispensable. In addition, C. glabrata is less resistant to menadione than C. albicans in SP. The S. cerevisiae laboratory reference strain is less resistant to menadione than C. glabrata and C. albicans; however S. cerevisiaeclinical isolates (CIs) are more resistant than the lab reference strain. Furthermore, S. cerevisiae CIs showed an increased catalase activity. Interestingly, in SP C. glabrata and S. cerevisiae are more resistant to CHP than C. albicans and Cta1p plays no apparent role in detoxifying this oxidant.

Molecular epidemiology of Candida albicans and Candida glabrata strains isolated from intensive care unit patients in Poland

Paluchowska,Paulina; Tokarczyk,Marianna; Bogusz,Bozena; Skiba,Iwona; Budak,Alicja
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2014 Português
Relevância na Pesquisa
66.92%
Over the last decades, Candida spp have been responsible for an increasing number of infections, especially in patients requiring intensive care. Knowledge of local epidemiology and analysis of the spread of these pathogens is important in understanding and controlling their transmission. The aim of this study was to evaluate the genetic diversity of 31 Candida albicans and 17 Candida glabrata isolates recovered from intensive care unit patients from the tertiary hospital in Krakow between 2011-2012. The strains were typed by random amplified polymorphic DNA (RAPD) polymerase chain reaction using five primers (CD16AS, HP1247, ERIC-2, OPE-3 and OPE-18). The results of the present investigation revealed a high degree of genetic diversity among the isolates. No clonal relationship was found among the C. albicans strains, whereas two C. glabrata isolates were identical. The source of Candida infection appeared to be mostly endogenous; however, the presence of two clonal C. glabrata strains suggested the possibility of cross-transmission of these pathogens. Our study confirmed the high discriminatory power of the RAPD technique in the molecular typing of Candida clinical isolates. This method may be applied to the evaluation of transmission routes of pathogenic fungi on a local level.

Susceptibility of Candida albicans and Candida glabrata biofilms to silver nanoparticles in intermediate and mature development phases

Monteiro, Douglas Roberto; Takamiya, Aline Satie; Feresin, Leonardo Perina; Gorup, Luiz Fernando; Camargo, Emerson Rodrigues de; Botazzo Delbem, Alberto Carlos; Henriques, Mariana; Barbosa, Debora Barros
Fonte: Elsevier B.V. Publicador: Elsevier B.V.
Tipo: Artigo de Revista Científica Formato: 42-48
Português
Relevância na Pesquisa
66.86%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 2009/15146-5; Purpose: The aim of this study was to investigate the susceptibility of Candida albicans and Candida glabrata biofilm development, in their intermediate and maturation stages, to the influence of silver nanoparticles (SN). Methods: SN (5 nm) suspensions were synthesized via reduction of silver nitrate by a solution of sodium citrate. These suspensions were used to treat Candida biofilms for five hours, grown on acrylic surfaces for 24-h (intermediate stage) and 48-h (maturation stage), and their efficacy was determined by total biomass (using crystal violet staining) and colony forming units (CFUs) quantification. Results: SN promoted significant reductions (p < 0.05) in the total biomass and number of CPUs of Candida biofilms, ranging from 23% to 51.5% and 0.63 to 1.59-log(10), respectively. Moreover, there were no significant differences in the total biofilm biomass (p > 0.05), when the different stages of biofilm development (24 or 48 h) were exposed to SN. Comparing the number of CFUs between 24- and 48-h biofilms treated with SN, a significant difference (p < 0.05) was found only for the C. albicans 324LA/94 strain. Conclusions: In general...