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Item Estresse oxidativo em células SH-SY5Y diante da exposição ao peróxido de hidrogênio(CDRR Editors) Zabeu, Antonieta Marques Caldeira; Rossato, Rafaella Carvalho; Pacheco-Soares, Cristina; Silva, Newton Soares daO estresse oxidativo é consequência da formação excessiva de espécies reativas de oxigênio geradas normalmente pelo metabolismo celular. Essa produção excessiva ocasiona a perda de capacidade de defesa e de reparo, levando a danos nas biomoléculas (DNA, lipídios, proteínas) celulares. Quando estes danos não são reparados, acabam comprometendo o funcionamento da célula, levando-a a morte por apoptose ou necrose. O estresse oxidativo está associado à morte de células neurais como sendo uma das principais causas de doenças neurodegenerativas, incluindo doença de Alzheimer e doença de Parkinson. O objetivo deste estudo é verificar a ação do peróxido de hidrogênio sendo um modelo de estresse oxidativo em células de neuroblastoma humano. Busca-se analisar a partir de qual concentração ocorre um estresse significante nas células e, em conjunto, verificar esse limiar de concentração em diferentes tempos de ação nas células. Os experimentos realizados compreenderam as análises de atividade mitocondrial obtido por meio do teste de corante tetrazólio (MTT), teste de viabilidade celular utilizando o ensaio de azul de tripano, obtendo-se assim dados quantitativos e qualitativos. Foi possível observar que, a partir da concentração de 0,2 mM durante um intervalo de tempo de 2 horas houve uma diminuição significativa no número de células viáveis em relação ao grupo controle. E, acima dessa concentração, em relação ao tempo, ocorreram mais danos celulares.Item Photobiomodulation assay of muscle cells C2C12 after irradiation with LED device(CDRR Editors) Lima, Elessandro Váguino de; Pacheco-Soares, Cristina; Silva, Newton Soares daIntroduction:One of the ways that have been observed to reduce musculoskeletal fatigue is the use of protocols for the application of light sources (photobiomodulation) such as low-intensity laser and LED (Light Emitting Diode). Work involving photobiomodulation has shown promising results in strength performance or reduction of muscle fatigue. At the cellular level,photobiomodulation can modulate fibroblasts proliferation, the fixation and synthesis of collagen and procollagen, promote angiogenesis and improving energy metabolism in mitochondria. Compared with laser devices, LED has several advantages, such as beingsmaller, lighter, lower cost, and easier for operation. Objective:The present work objective is to verify if irradiation with LED device (650 nm and 860 nm) in muscle cells C2C12 modify the viability, morphology and cytoskeleton components. Methodology:C2C12 cells line (ATCC CRL -1772) were cultured in 25 cm2bottles at 37ºC under 5% CO2in DMEM. The cells wereirradiated with the light-emitting diodes (LED) device, Sportllux Ultra that consists of 84 LEDs, each individual LED has 8 mW of power, emitting in 660±20 nm (42 LEDs) and 850±20 nm (42 LEDs), and covering anarea (A) of 120 cm2. The power density of delivered light was 5,6 mW/cm2, and the exposure time was 10 minutes, totalizing the fluence of 3,4 J/cm2. Viability assay was performed where the cells were incubated with 100 μL of Crystal Violet (CV) solution and mitochondrial activity assay was evaluated by the colorimetric MTT assay. Nucleus (DAPI) and Cytoskeleton (Rhodamine Phalloidin) fluorescence assay was performed to study the cytoskeleton based on the change in the actin filaments. Results:Our results demonstrate that the synergism of LED irradiation (660nm and 850nm) induced the proliferation of C2C12 cells. The light-emitting diode (LED) device, Sportllux Ultra has a significant effect on C2C12 cell culture. Mitochondrial activity and cell viability showed a significative increase in their activities after irradiation. The microscopy fluorescence observations showed an alignment of cytoskeletal components of C2C12 cells after irradiation.Conclusion:The application of irradiation with the Sportlux Ultra LED device stimulated an increase of energy by mitochondrial activity assay, number of cells by cell viability assay and alignment of cytoskeleton components by fluorescence assay in C2C12line cells. Our results suggest that organizated cytoskeletal actin filaments normally contribute to cell survival and that induced major cell changes in the cytoskeleton that result in cell shape change. These results suggest that the Sport Lux Ultra LEDdevice can help in the repair of tissue injuries and to collaborate to increase of performance in athletes in a faster wayItem Specific nanomarkers fluorescence: in vitro analysis for EGFR overexpressed cells in triple-negative breast cancer and malignant glioblastoma(Elsevier) Vieira, Paula Fonseca Antunes; Jesus, Viviane Paula dos Santos; Cândido, Marcela Aparecida; Pacheco-Soares, Cristina; Castilho, Maiara Lima; Raniero, Leandro JoséBackground: Epidermal Growth Factor Receptor (EGFR receptor) is encoded by the EGFR gene. EGFR receptor signaling pathways are activated by EGF protein, regulating cell actions. Overexpression of EGFR receptor may be linked to malignancies with a poor prognosis. As a result, EGFR receptor is being studied for a variety of tumor diagnostics, spurring the development of innovative approaches to increase quality and efficiency. Nanomaterials can recognize cancer cells by specifically targeting of molecular pathways, underscoring the importance of nanomedicine. In this study, we synthesized EGFR-specific nanomarkers by functionalizing EGF protein and Chlorin e6 in gold nanoparticles. These nanoparticles use active targeting to deliver EGF protein to EGFR receptor, and Chlorin e6 serves as a fluorescent marker molecule Methods: Nanomarkers were examined in vitro in MDA-MB-468 and M059J cell lines. Confocal microscopy and flow cytometry were used to examine the distribution, uptake, internalization, and fluorescence intensity of nanomarkers in vitro Results: The results show that both lines examined accumulate nanomarkers. However, MDA-MB-468 had the highest intensity due to its EGFR receptor overexpression properties Conclusion: The findings point to ideal properties for detecting EGFR receptor overexpressed cells.Item Photodynamic effect of protoporphyrin IX in gliosarcoma 9l/lacZ cell line(Elsevier B.V.) Fontana, Letícia Corrêa; Pinto, Juliana Guerra; Vitorio, Gabrielle dos Santos; Ferreira, Isabelle; Pacheco-Soares, Cristina; Mamone, Leandro; Ferreira‐Strixino, JulianaPhotodynamic Therapy (PDT) is an oncologic treatment, producing reactive oxygen species (ROS) to induce the death of cancer cells. This study aimed to evaluate the action of PDT on gliosarcoma cells, using protoporphyrin IX as PS by incubation with the precursor aminolevulinic acid (ALA). An LED device was used with a light dose of 10 J/cm². The success of the therapy proved to be dependent on the concentration of ALA, and an incubation time of 4 h required for an effective response. Cell death was prevalent due to necrosis when assessed 18 h post-PDT. ALA proved to be an option to PDT in cells of the 9 L/lacZ, with the protocol tested.Item Evaluation of the effect of hydrocortisone in 2D and 3D HEp-2 cell culture(CDRR Editors) Fonseca, Marcelo de Oliveira; Godoi, Bruno Henrique; Silva, Newton Soares da; Pacheco-Soares, CristinaIntroduction: Cancer is one of the diseases with the highest incidence globally and that associated with the patient'semotional state, can act positively or negatively in the treatment. Cortisol is a principal primary stress hormone in the human body. The corticoids can increase cell proliferation and reactive oxygen species that contribute to DNA damage. Prolonged exposure to stress can contribute to tissues becoming insensitive to cortisol, the primary human stress hormone. Objective: This study explores cortisol's influence on tumor cell development, particularly in human cells of carcinoma of the human laryngeal (HEp-2). Methodology: HEp-2 cells were exposed toincreasing cortisol (hydrocortisone) concentrations for 24 or 48 hours, and cytotoxicity (MTT assay) proliferation assay (crystal violet assay), and immunolabeled 3D culture for fibronectin and FAK were analyzed. Results: The group treated with hydrocortisone showed a significant increase in mitochondrial activity, as for the evaluation by the violet crystal, the treated group showed similar behavior to the control. The 3D culture showed dispersed cells within 24hours with reduced FAK labeling; however, no changes were observed within 48 hours. Conclusion: Although some cases favored corticosteroid use in cancer patients, a more detailed analysisis necessary before prescribing them.Item Comparison of the Photodynamic Effect of Two Chlorins, Photodithazine and Fotoenticine, in Gliosarcoma Cells(MDPI) Fontana, Letícia Corrêa; Pinto, Juliana Guerra; Magalhães, Jéssica Aparecida; Tada, Dayane Batista; Almeida, Rainara Moreno Sanches de; Pacheco-Soares, Cristina; Ferreira-Strixino, JulianaThe treatment and prognosis of cancers of the nervous system remain unfavorable to the patient, which makes it necessary to study alternative therapies as primary or adjuvant treatments to existing methods. Photodynamic Therapy (PDT) is a method that consists of combining a photosensitizer (PS), a light source at the appropriate wavelength, and molecular oxygen, forming reactive oxygen species (ROS), leading to death in the target cell. The objective of this work was to compare the effects of PDT with two chlorins, Photodithazine (PDZ) and Fotoenticine (FTC), in 9L/lacZ gliosarcoma cell lines. Both chlorins, together with an LED device at 660 nm with a fluence of 10 J/cm2 , were included in the study. It was observed that the response to therapy depends on the concentration and type of PS used. In addition, PDZ showed a higher quantum yield of singlet oxygen generation than FTC.Item Ação de extrato de folhas de Acmella oleracea (L.) R. K. Jansen em co-cultivo de Staphylococcus aureus e L929 (fibroblastos) simulando processo de celulite infecciosa(CDRR Editors) Silva, Laís Eduarda; Silva, Carlos Augusto Priante da; Pacheco-Soares, Cristina; Silva, Newton Soares daIntrodução: A bactéria Staphylococcus aureus é o agente etiológico de maior incidência nas infecções de pele, dentre elas a celulite infecciosa. Seu tratamento é contido por antibióticos, porém o uso de plantas medicinais vem sendo utilizadas para tratamento. Acmella oleracea é uma planta da família Asteraceae conhecida como jambu. Objetivos: Avaliar a ação do extrato das folhas de Acmella oleracea em co-cultivo da linhagem celular L929 e bactérias Staphylococcus aureus simulando o processo de celulite infecciosa. Metodologia: Foi realizado primeiramente o teste MTT e Cristal Violeta na linhagem celular L929 incubadas com o extrato do jambu, nas concentrações 500 µg/mL, 1000 µg/mL e 2000 µg/mL. Foi realizado ensaios com Staphylococcus aureus incubado no período de 24 horas com o extrato do jambu nas mesmas concentrações. Resultados: Na avaliação das células L929 no teste MTT houve uma significância na concentração de 1000 µg/mL apresentando uma baixa atividade metabólica em relação as outras concentrações. No teste cristal violeta ocorreu um maior estímulo nas demais concentrações quando comparado ao controle. Na viabilidade da bactéria observou-se uma queda significativa da viabilidade quando comparado ao controle. A concentração de 500 ug/mL foi que apresentou um menor índice de UFC. Ao realizar o teste do co-cultivo L929 - S. aureus após a incubação de 24 horas com diferentes concentrações do extrato, foi possível avaliar que a ação do extrato apresentou uma redução significativa na viabilidade bacteriana e não interferência à viabilidade das células L929. Conclusão: Com estes resultados demonstramos que o extrato de Acmella oleracea apresentou uma atividade antimicrobiana sem interferir na linhagem de fibroblastos L929, sendo assim podendo ser utilizada contra a celulite infecciosa.Item Photodynamic therapy using silicon phthalocyanine conjugated with bovine serum albumin as a drug delivery system(IOP science) Silva, Emanoel Pedro de Oliveira; Ribeiro, Natalia Mazini; Cardoso, Maria Angélica Gargione; Pacheco-Soares, Cristina; Beltrame Junior, MiltonIn the present study, we describe a new silicon phthalocyanine conjugated to bovine serum albumin (PcSiN3M-BSA) and its photodynamic activity in murine macrophages cells (J774.A1). The nonconjugated precursor, bis(trimethylaminoethanoxy)–phthalocyaninato silicon (IV) (PcSiN3M), was also studied. Compounds PcSiN3M and PcSiN3M-BSA showed no cytotoxicity in the dark, but exhibited high photodynamic activities following exposure to 5 μM photosensitizers and 45 J cm−2 irradiation. These conditions were sufficient to decrease the cell viability to 40% and 5% in cells treated with PcSiN3M and PcSiN3M-BSA, respectively. These results demonstrated an increase of 87% in the photodynamic activity of PcSiN3M when conjugated with BSA. The results shown in this work suggest that PcSiN3M-BSA had higher uptake by J774.A1 cells, which contributed to its higher photoactivity compared with the unconjugated form, PcSiN3N.