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Item Ação da terapia fotodinâmica com curcumina na interação de macrófagos e amastigotas de L. braziliensis e L. major(2021-09-21) Ferreira-Strixino, Juliana; Soares, Cristina Pacheco; Silva, Newton Soares da; Ribeiro, Martha Simões; Lindoso, José Angelo Lauletta; Pereira, André Henrique Correia; São José dos CamposA leishmaniose tegumentar (LT) é uma doença negligenciada que está entre as 10 doenças infecciosas mais importantes do mundo. O tratamento convencional é feito com antimoniais pentavalentes e anfotericina, medicamentos que apresentam diversos efeitos colaterais e contraindicações. A terapia fotodinâmica (TFD) com curcumina surge como alternativa no tratamento da LT, visto que se baseia em aplicação local, não invasiva e seletiva, enquanto utiliza um composto natural de baixo custo como fotossensibilizador. Esse trabalho teve por objetivo a avaliação, in vitro, da TFD aplicada sobre amastigotas de L. braziliensis e L. major em interação com macrófagos por meio de análise de viabilidade, morfologia, internalização do FS, atividade e potencial de membrana mitocondrial e recuperação de parasitos pósTFD. Foram utilizadas concentrações de curcumina em diluições seriadas, de 500 a 7,8 µg.mL-1, e irradiação com luz azul (450 nm), irradiância de 36 mW/cm² e fluência de 10 J/cm². Os resultados demonstram ampla inativação e baixa citotoxicidade da TFD com curcumina em macrófagos infectados e não infectados nas concentrações de 15,6 e 7,8 µg.mL-1. A internalização do FS demonstrou localização do composto em todo o citoplasma da célula, além de concentração no núcleo, e nos amastigotas intracelulares. A morfologia pós-tratamento se mostrou alterada, exibindo destruição celular nos grupos submetidos à TFD, enquanto os grupos não tratados permaneceram com a morfologia dos macrófagos preservada. Foi observada elevação do potencial de membrana mitocondrial e diminuição da atividade mitocondrial nos grupos que receberam a terapia. Além disso, a contagem de parasitos recuperados pós-TFD demonstrou que houve diminuição do número de parasitos viáveis, indicando que a terapia pôde inativar não só os macrófagos, mas também os amastigotas intracelulares para as duas espécies de Leishmania estudadas. Os testes realizados demonstraram potencial da TFD com curcumina nas concentrações de 15,6 e 7,8 µg.mL-1, promovendo a inativação de macrófagos infectados com Leishmania, bem como alterações celulares morfológicas e nopotencial de membrana e atividade mitocondrial.Item Evaluation of the Photodynamic Therapy with Curcumin on L. braziliensis and L. major Amastigotes(MDPI) Pereira, André Henrique Correia; Marcolino, Luciana Maria Cortez; Pinto, Juliana Guerra; Strixino, Juliana FerreiraCutaneous leishmaniasis (CL) is a neglected disease prevalent in tropical countries with the ability to cause skin lesions. Photodynamic therapy (PDT) represents a specific and topical option for the treatment of these lesions. This study evaluated the response of macrophages infected with L. braziliensis and L. major to PDT with curcumin. Curcumin concentrations were evaluated in serial dilutions from 500.0 to 7.8 μg/mL using LED (λ = 450 ± 5 nm), with a light dose of 10 J/cm2. The Trypan blue viability test, ultrastructural analysis by scanning electron microscopy (SEM), mitochondrial polarity by Rhodamine 123 (Rho 123), curcumin internalization by confocal microscopy, and counting of the recovered parasites after the PDT treatment were performed. The lowest concentrations of curcumin (15.6 and 7.8 μg/mL) presented photodynamic inactivation. Cell destruction and internalization of curcumin in both macrophages and intracellular parasites were observed in microscopy techniques. In addition, an increase in mitochondrial membrane polarity and a decrease in the number of parasites recovered was observed in the PDT groups. This study indicates that PDT with curcumin has the potential to inactivate infected macrophages and might act as a basis for future in vivo studies using the parameters herein discussed.Item Efficiency of Antimicrobial Photodynamic Therapy with Photodithazine® on MSSA and MRSA Strains(MDPI) Souza, Beatriz Müller Nunes; Pinto, Juliana Guerra; Pereira, André Henrique Correia; Miñán, Alejandro Guillermo; Strixino, Juliana FerreiraStaphylococccus aureus is a ubiquitous and opportunistic bacteria associated with high mortality rates. Antimicrobial photodynamic therapy (aPDT) is based on the application of a light source and a photosensitizer that can interact with molecular oxygen, forming Reactive Oxygen Species (ROS) that result in bacterial inactivation. This study aimed to analyze, in vitro, the action of aPDT with Photodithazine® (PDZ) in methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) strains. The strains were incubated with PDZ at 25, 50, 75, and 100 mg/L for 15 min and irradiated with fluences of 25, 50, and 100 J/cm2. The internalization of PDZ was evaluated by confocal microscopy, the bacterial growth by counting the number of colony-forming units, as well as the bacterial metabolic activity post-aPDT and the production of ROS. In both strains, the photosensitizer was internalized; the production of ROS increased when the aPDT was applied; there was a bacterial reduction compared to the control at all the evaluated fluences and concentrations; and, in most parameters, it was obtained complete inactivation with significant difference (p < 0.05). The implementation of aPDT with PDZ in clinical strains of S. aureus has resulted in its complete inactivation, including the MRSA strains.Item Antimicrobial effects of photodynamic therapy with Fotoenticine on Streptococcus mutans isolated from dental caries(Elsevier) Terra-Garcia, Maíra; Souza, Cheyenne Marçal de; Gonçalves, Nathalia Maria Ferreira; Pereira, André Henrique Correia; Barros, Patrícia Pimentel de; Borges, Alessandra Bühler; Miyakawa, Walter; Ferreira-Strixino, Juliana; Junqueira, Juliana CamposPhotodynamic therapy (PDT) is a promising strategy to control cariogenic pathogens, such as Streptococcus mutans. Seeking to reach the total bacterial elimination from dental surfaces, novel photosensitizers have been investigated, such as Fotoenticine (FTC) derived from chlorin e6. The objective of this study was to investigate the photodynamic effects of FTC against several clinical strains of S. mutans. Clinical isolates were obtained from patients with active carious lesions, identified by molecular analysis and subjected to PDT using laser irradiation (660 nm and 39.5 J/cm2) in planktonic and biofilm stages. We identified 11 S. mutans strains from cervical, occlusal and proximal caries. PDT mediated by FTC has totally eliminated the S. mutans cells in planktonic growth for all analyzed strains. In biofilms, PDT with FTC reached statistically significant reductions compared with the non-treated control group, at 5.4, 5.5 and 6.5 Log10 (CFU/mL), respectively, for the strains from proximal, occlusal and cervical caries. The scanning electron microscopy evaluations confirmed that PDT mediated by FTC was able to disaggregate and kill the S. mutans cells adhered to enamel surface, suggesting its potential to disinfect the dental tissues.