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Item Efeito dos compostos de organoselênio (PhSe)2, (MeOPhSe)2, (p-Cl-PhSe)2 em biofilmes dupla-espécie de Candida albicans e Candida krusei(2024-07-31) Costa, Maricília Silva; Canevari, Renata de Azevedo; Silva, Carlos Alberto; Calvi, Gabriela de Souza; São José dos CamposO gênero Candida é o mais comumente isolado em culturas de pacientes acometidos com infecções causadas por fungos. A espécie Candida albicans é, entre o gênero, a mais comum, e a espécie Candida krusei, é considerada emergente. Ambas as espécies já demonstram resistência aos fármacos convencionais, como o fluconazol e as equinocandinas. Além disso, ambas são plenamente capazes de formar biofilmes. Biofilmes são estruturas complexas capazes de abrigar mais de uma espécie de microrganismo, alcançando características ainda mais resistentes. Os compostos de organoselênio, principalmente o disseleneto de difenila e derivados, são estruturas químicas simples que apresentam atividade antifúngica, tornando-os promissores para a inibição de biofilmes dupla-espécie. O objetivo da pesquisa foi analisar o efeito dos compostos (PhSe)2, (MeOPhSe)2, (p-Cl-PhSe)2 nas fases de adesão de ambas as espécies em conjunto, e no biofilme misto, nas fases de formação e biofilme maduro. Para a formação dos biofilmes, foram utilizados dois meios, o RPMI-1640 e o Sabouraud dextrose. Para avaliar a viabilidade dos biofilmes, foi mensurada a atividade metabólica, e a diferenciação das espécies por CHROMagar Candida® foi realizada. Os resultados demonstram que os compostos possuem capacidade de inibir os biofilmes dupla-espécie, especialmente nas fases de adesão e formação. O composto (MeOPhSe)2 demonstrou capacidade de inibir a formação dos biofilmes dupla-espécie, obtendo resultados de até 95%, sendo mais significativo que (PhSe)2 e (p-Cl-PhSe)2 que inibiram a formação em 56% e 27% respectivamente. Sendo assim, conclui-se que os compostos de organoselênio são terapias promissoras para o combate destes biofilmes.Item Inhibition of Development and Metabolism of Dual-Species Biofilms of Candida albicans and Candida krusei (Pichia kudriavzevii) by Organoselenium Compounds(MDPI) Calvi, Gabriela de Souza; Cartaxo, Giulia Nicolle Jácome; Carretoni, Qiuxin Lin; Silva, André Luiz Missio da; Moraes, Denilson Nogueira de; Pradella, José Geraldo da Cruz; Costa, Maricilia SilvaAlthough Candida albicans is the most frequently identified Candida species in clinical settings, a significant number of infections related to the non-albicans Candida (NAC) species, Candida krusei, has been reported. Both species are able to produce biofilms and have been an important resistance-related factor to antimicrobial resistance. In addition, the microbial relationship is common in the human body, contributing to the formation of polymicrobial biofilms. Considering the great number of reports showing the increase in cases of resistance to the available antifungal drugs, the development of new and effective antifungal agents is critical. The inhibitory effect of Organose- lenium Compounds (OCs) on the development of Candida albicans and Candida krusei was recently demonstrated, supporting the potential of these compounds as efficient antifungal drugs. In addition, OCs were able to reduce the viability and the development of biofilms, a very important step in colo- nization and infection caused by fungi. Thus, the objective of this study was to investigate the effect of the Organoselenium Compounds (p-MeOPhSe)2, (PhSe)2, and (p-Cl-PhSe)2 on the development of dual-species biofilms of Candida albicans and Candida krusei produced using either RPMI-1640 or Sabouraud Dextrose Broth (SDB) media. The development of dual-species biofilms was evaluated by the determination of both metabolic activity, using a metabolic assay based on the reduction of XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide sodium salt) assay and identification of either Candida albicans and Candida krusei on CHROMagar Candida medium. Biofilm formation using RPMI-1640 was inhibited in 90, 55, and 20% by 30 μM (p-MeOPhSe)2, (PhSe)2, and (p-Cl-PhSe)2, respectively. However, biofilms produced using SDB presented an inhibition of 62, 30 and 15% in the presence of 30 μM (p-MeOPhSe)2, (PhSe)2, and (p-Cl-PhSe)2, respectively. The metabolic activity of 24 h biofilms was inhibited by 35, 30 and 20% by 30 μM (p-MeOPhSe)2, (PhSe)2, and (p-Cl-PhSe)2, respectively, with RPMI-1640; however, 24 h biofilms formed using SDB were not modified by the OCs. In addition, a great reduction in the number of CFUs of Candida albicans (93%) in biofilms produced using RPMI-1640 in the presence of 30 μM (p-MeOPhSe)2 was observed. However, biofilms formed using SDB and treated with 30 μM (p-MeOPhSe)2 presented a reduction of 97 and 69% in the number of CFUs of Candida albicans and Candida krusei, respectively. These results demonstrated that Organoselenium Compounds, mainly (p-MeOPhSe)2, are able to decrease the metabolic activity of dual-species biofilms by reducing both Candida albicans and Candida krusei cell number during biofilm formation using either RPMI-1640 or SDB. Taken together, these results demonstrated the potential of the OCs to inhibit the development of dual-species biofilms of Candida albicans and Candida krusei.Item Anti‐inflammatory effect of photobiomodulation in the brain following local peripheral carrageenan‐induced inflammation(Springer) Silva, Carlos Alberto; Calvi, Gabriela de Souza; Feliciano, Regiane dos Santos; Silva Junior, José Antônio; Costa, Maricilia SilvaPurpose Photobiomodulation (PBM) has been suggested as a potential anti-inflammatory therapy, presenting excellent outcomes for several disorders. Reduction in COX-2 mRNA expression in subplantar and brain tissues by PBM was dem- onstrated, using the classic model of oedema formation and hyperalgesia induced by Carrageenan (Carr). This work inves- tigated the effect of PBM on mRNA expression of key inflammation-related genes (IL-1β, mPGES-1, mPGES-2 and EP) in subplantar and brain tissues obtained from rats receiving Carr. Methods The animals were treated with Carr, treated with PBM after 1 h and sacrificed after 1, 3 and 6 h. The light source used was a diode laser, with output power of 30 mW and a wavelength of 660 nm. The laser beam illuminated an area of 0.785 cm2, resulting in an energy dosage of 7.5 J/cm2, applied for 196 s. IL-1β, mPGES-1, mPGES-2 and EP mRNAs were determined by RT-PCR. Results It was observed a reduction in IL-1β expression as in subplantar tissue as in brain parenchyma in animals treated with PBM. In addition, the expression of both mPGES-1 and mPGES-2 mRNA was decreased after PBM. Conclusion These results suggested that PBM could reduce the production of IL-1β and subsequently decreasing the effects of PGE2. Therefore, the possible mechanism by which PBM alleviates hyperalgesia could involve its ability to decrease the expression of inflammatory markers in the CNS, reducing the production of PGE2 in the spinal cord.Item Antimicrobial Photodynamic Therapy with Polystyrene Nanoparticles, Encapsulated Porphyrin-Derivative and Iodine Generation against Candida AlbicansCalvi, Gabriela de Souza; Braga, Marilia Toledo; Cartaxo, Giulia Nicolle Jácome; Liška, Vojtěch; Mosinger, Jiří; Costa, Maricília Silva; Paris