4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
Item (MeOPhSe)2, a synthetic organic selenium compound, inhibits virulence factors of Candida krusei: Adherence to cervical epithelial cells and biofilm formation(Elsevier GmbH.) Siqueira, Victor Mendes de; Silva, Bruna Graziele Marques da; Passos, Juliene Cristina da Silva; Pinto, Ana Paula; Rocha, João Batista Teixeira da; Silva, Carlos Alberto; Costa, Maricília SilvaBackground: Systemic candidiasis is produced by Candida albicans or non-albicans Candida species, opportunistic fungi that produce both superficial and invasive infections. Despite the availability of a wide range of antifungal agents for the treatment of candidiasis, failure of therapy is observed frequently, which opens new avenues in the field of alternative therapeutic strategies. Methods: The effects of p,p′ -methoxyl-diphenyl diselenide [(MeOPhSe)2], a synthetic organic selenium (organochalcogen) compound, were investigated on virulence factors of C. krusei and compared with its antifungal effects on the virulence factors related to adhesion to cervical epithelial cell surfaces with C. albicans. Results: (MeOPhSe)2, a compound non-toxic in epithelial (HeLa) and fibroblastic (Vero) cells, inhibited the growth in a dose-dependent manner and changed the kinetics parameters of C. krusei and, most importantly, extending the duration of lag phase of growth, inhibiting biofilm formation, and changing the structure of biofilm. Also, (MeOPhSe)2 reduced C. albicans and C. krusei adherence to cervical epithelial cells, an important factor for the early stage of the Candida-host interaction. The reduction was 37.24 ± 2.7 % in C. krusei (p = 0.00153) and 32.84 ± 3.2 % in C. albicans (p = 0.0072) at 20 μM (MeOPhSe)2, and the effect is in a concentration-dependent manner. Surprisingly, the antifungal potential on adhesion was similar between both species, indicating the potential of (MeOPhSe)2 as a promising antifungal drug against different Candida infections. Conclusion: Overall, we demonstrated the potential of (MeOPhSe)2 as an effective antifungal drug against the virulence factors of Candida species.Item Diphenyl diselenide suppresses key virulence factors of Candida krusei, a neglected fungal pathogen(Taylor & Francis) Silva, Bruna Graziele Marques da; Pinto, Ana Paula; Passos, Juliene Cristina da Silva; Rocha, João Batista Teixeira da; Silva, Carlos Alberto; Costa, Maricilia SilvaCandida krusei is a candidiasis etiological agent of relevance in the clinical setting because of its intrinsic resistance to fluconazole. Also, it has opened up new paths in the area of alternative therapeutic techniques. This project demonstrated the effects of diphenyl diselenide (PhSe)2 and p-cloro diphenyl diselenide (pCl-PhSe)2, two organochalcogen compounds, on relevant virulence factors for the early stage of the C. krusei host interaction and infection process. Both com- pounds inhibited adherence of C. krusei to both polystyrene surfaces and cervical epithelial cells and biofilm formation; the structure of the biofilm was also changed in a dose-dependent man- ner. In addition, both compounds inhibited C. krusei growth, but (PhSe)2 significantly increased the time duration of the lag phase and delayed the start of the exponential phase in growth kinetics. (PhSe)2 has more potential antifungal activity than (pCl-PhSe)2 in inhibiting the adher- ence to epithelial cells, biofilm formation, and growth of C. krusei.Item (PhSe)2 and (pCl-PhSe)2 organochalcogen compounds inhibit Candida albicans adhesion to human endocervical (HeLa) cells and show anti- biofilm activities(Taylor & Francis) Silva, Bruna Marques da; Braga, Marília Toledo; Passos, Juliene Cristina da Silva; Carvalho, Moisés Lopes; Rosseti, Isabela Bueno; Amorim, Laís Mayara Machado de; Rocha, João Batista Teixeira da; Silva, Carlos Alberto; Costa, Maricilia SilvaAdhesion capacity on biological surfaces and biofilm formation is considered an important step in the infection process by Candida albicans. The ability of (PhSe)2 and (pCl-PhSe)2, two synthetic organic selenium (organochalcogen) compounds, to act on C. albicans virulence factors related to adhesion to human endocervical (HeLa) cell surfaces and their anti-biofilm activities was ana- lyzed. Both organochalcogen compounds inhibited C. albicans adhesion to HeLa cells, depend- ent on compound concentrations. (PhSe)2 (at 20 mM; p 1⁄4 0.0012) was significantly more effective than (pCl-PhSe)2 (at 20 mM; p 1⁄4 0.0183) compared with the control. (PhSe)2 inhibited biofilm for- mation and decreased biofilm viability in both early and mature biofilms more efficiently than (pCl-PhSe)2. Overall, the organochalcogen compounds, especially (PhSe)2, were demonstrated to be effective antifungal drugs against C. albicans virulence factors related to epithelial cell surface adhesion and the formation and viability of biofilms.Item The arrangement of dual-species biofilms of Candida albicans and Issatchenkia orientalis can be modified by the medium: effect of Voriconazole(Taylor & Francis) Passos, Juliene Cristina da Silva; Rodrigues, Ana Beatriz Furtado; Silva, Carlos Alberto; Costa, Maricilia SilvaBoth Candida albicans and Issatchenkia orientalis have been isolated from different types of infections over the years. They have the ability to form communities of microorganisms known as biofilms. It has been demonstrated that the medium employed in studies may affect the biofilm development. The aim of this study was to investigate the arrangement of dual-species biofilms of C. albicans and I. orientalis cultivated on either RPMI-1640 or Sabouraud Dextrose Broth (SDB), as well as the inhibitory effect of Voriconazole (VRC). For the experiments performed, ATCC strains were used, and yeast-mixed suspensions were inoculated in 96-well plates with either RPMI-1640 or SDB, in the presence or absence of VRC. The results were observed by counting the number of CFU obtained from scraping off the biofilms produced and plating the content on CHROMagar Candida medium. It was observed that for all conditions tested the medium chosen affected the arrangement of dual-species biofilms: when RPMI-1640 was used, there was a prevalence of C. albicans, while the opposite was noted when SDB was used. It could be suggested that the medium and environment could regulate interactions between both yeast species, including the response to different antifungal drugs.