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Item Modulation of heat shock protein expression and cytokine levels in MCF‐7 cells through photodynamic therapy(Springer-Verlag London Ltd.) Santos, Mariela Inês Batista dos; Godoi, Bruno Henrique; Silva, Newton Soares da; Oliveira, Luciane Dias de; Ramos, Lucas de Paula; Cintra, Ricardo Cesar; Pacheco‐Soares, CristinaIn this study, we assess the impact of photodynamic therapy (PDT) using aluminum phthalocyanine tetrasulfonate (AlPcS4) on the viability and cellular stress responses of MCF-7 breast cancer cells. Specifically, we investigate changes in cell viability, cytokine production, and the expression of stress-related genes. Experimental groups included control cells, those treated with AlPcS4 only, light-emitting diode (LED) only, and combined PDT. To evaluate these effects on cell viability, cytokine production, and the expression of stress-related genes, techniques such as 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, enzyme-linked immunosorbent assays (ELISA), and real-time quantitative PCR (RT‒qPCR) were employed. Our findings reveal how PDT with AlPcS4 modulates mitochondrial activity and cytokine responses, shedding light on the cellular pathways essential for cell survival and stress adaptation. This work enhances our understanding of PDT's therapeutic potential and mechanisms in treating breast cancer.Item Biomodulatory effect of low intensity laser (830 nm.) in neural model 9L/lacZ(CDRR Editor) Zabeu, Antonieta Marques Caldeira; Carvalho, Isabel Chaves Silva; Soares, Cristina Pacheco; Silva, Newton Soares daCurrently, research is advancing with low-intensity laser (LIL) in cells of the central nervous system, with the aim of evaluating the benefits of this therapy in neurological disorders such as Alzheimer's, stroke, ischemia, epilepsy, among others. The aim of this study was to verify the biomodulatory and biostimulatory effects of LIL in neural cell culture. Diode laser at wavelength λ = 830 nm, power 40 mW, in continuous mode, was applied on the 9L/lacZ cell line with energy densities of 0.5 to 3 J/cm . The analysis was performed 24 hours after irradiation, the results of cell viability showed a difference between the control and irradiated groups. As for the occurrence of apoptosis, no significant manifestation was observed between the control group compared to the irradiated group (P = 0.9956); there was a significant difference between apoptosis and death by necrosis between the control and treated groups (P<0.001). In the comet assay no statistically significant differences were observed. Regarding the objective of evaluating whether LIL promotes early activation of apoptosis or proliferation of 9L/lacZ cells at different energy densities of the infrared diode laser, we observed an increase in the number of neural cells, highlighting the action of biomodulation. Furthermore, LIL did not promote the activation of programmed cell death - apoptosis and did not show any indication of DNA damage by the comet assay. The results of this study are indicative that the laser in the near infrared has a positive interaction with neuronal cells.Item Tribocorrosion Susceptibility and Cell Viability Study of 316L Stainless Steel and Ti6Al4V Titanium Alloy with and without DLC Coatings(MDPI) Sene, Ana Claudia; Silva, Michely Glenda Pereira da; Macário, Paulo Fabrício; Vieira, Angela Aparecida; Leite, Priscila Maria Sarmeiro Correa Marciano; Silva, Newton Soares da; Marques, Francisco Das Chagas; Vieira, LúciaStainless steel (SS316L) and titanium alloy (Ti6Al4V) exhibit suitable properties for biomed- ical applications; however, the tribocorrosion of these materials, which is associated with metallosis, is still a significant concern. This work investigates the effectiveness of DLC smoothing coatings applied to the metals to reduce tribocorrosion and improve cell viability. The study was motivated by many reports of metallosis caused by metal debris in the soft tissues of the body. DLC coatings were produced using the plasma-enhanced chemical vapor deposition (PECVD) technique. The cytotoxicity, genotoxicity, and cell viability of metallic samples with and without DLC coatings were analyzed, considering the chemical composition of the coating and metallic components. The results show that the DLC coatings presented suitable interaction properties and no cytotoxicity or genotoxicity when exposed to the cellular environment, compared with the control group (p < 0.0001). They also demonstrated cell viability, low friction representing a reduction of 80%, and hardness 23–26 GPa, making them ideal for use on fixed implants. It is necessary to control the thickness and roughness of the coating to avoid pinholes and increase the corrosion protection of implants. These DLC coatings with low friction coefficients could facilitate the fixation of implantable pins and screws, including Kirschner wires.Item In vitro evaluation of red and near infrared LED photobiomodulation on L929 fibroblasts metabolic activity and morphology(Springer) Segismondi, Larissa Cavallieri; Soares, Luís Eduardo Silva; Pacheco-Soares, CristinaPurpose Fibroblasts, the main cells of connective tissue, are highly susceptible to oxidative stress caused by reactive oxygen species (ROS). Photobiomodulation (PBM) has emerged as a promising therapy capable of modulating biological tissues, enhancing cellular metabolic activity, and promoting the proliferation and survival of fibroblasts. In this study, we aimed to investigate the potential in vitro photoprotective effect of cellular photomodulation using 660 and 850 nm LEDs in L929 fibroblast cells treated with hydrogen peroxide as a model of oxidative stress. Methods Changes in cell viability were observed using the Alamar Blue colorimetric assay, and cell morphology was assessed by inverted microscopy. Mitochondria and nuclei were also labeled in living cells using fluorescence with TMRM and Hoechst, in addition to ROS detection with CellRox Green. Results Our results indicate that pretreatment with LED exerts a cytoprotective effect against oxidative stress, promoting an increase in mitochondrial activity, mitochondrial membrane potential, and a reduction in intracellular reactive oxygen species (ROS) generation while inducing improvements in the morphological characteristics of cells. Conclusion The findings from the present study indicate that Photobiomodulation (PBM) with LED contributes to maintaining cellular homeostasis and can help prevent and mitigate damage resulting from oxidative stress in fibroblasts.Item In vitro evaluation of red and near infrared LED photobiomodulation on L929 fibroblasts metabolic activity and morphology(Springer) Segismondi, Larissa Cavallieri; Soares, Luís Eduardo Silva; Soares, Cristina PachecoPurpose Fibroblasts, the main cells of connective tissue, are highly susceptible to oxidative stress caused by reactive oxygen species (ROS). Photobiomodulation (PBM) has emerged as a promising therapy capable of modulating biological tissues, enhancing cellular metabolic activity, and promoting the proliferation and survival of fibroblasts. In this study, we aimed to investigate the potential in vitro photoprotective effect of cellular photomodulation using 660 and 850 nm LEDs in L929 fibroblast cells treated with hydrogen peroxide as a model of oxidative stress. Methods Changes in cell viability were observed using the Alamar Blue colorimetric assay, and cell morphology was assessed by inverted microscopy. Mitochondria and nuclei were also labeled in living cells using fluorescence with TMRM and Hoechst, in addition to ROS detection with CellRox Green. Results Our results indicate that pretreatment with LED exerts a cytoprotective effect against oxidative stress, promoting an increase in mitochondrial activity, mitochondrial membrane potential, and a reduction in intracellular reactive oxygen spe- cies (ROS) generation while inducing improvements in the morphological characteristics of cells. Conclusion The findings from the present study indicate that Photobiomodulation (PBM) with LED contributes to maintain- ing cellular homeostasis and can help prevent and mitigate damage resulting from oxidative stress in fibroblasts.