CAMILA RAMOS SILVA
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Artigo IPEN-doc 29934 Noninvasive red Laser intervention before radiotherapy of triple-negative breast cancer in a murine model2023 - SILVA, CAMILA R.; PEREIRA, SAULO T.; SILVA, DANIELA F.T.; PRETTO, LUCAS R. de; FREITAS, ANDERSON Z.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.; RIBEIRO, MARTHA S.In proton beam treatments, the superposition of several weighted Bragg curves with different incident energies is required to homogeneously irradiate a large tumor volume, creating a spread-out Bragg peak (SOBP). This paper confirms on the suitability of two different methods to create SOBPs – Bortfeld/Jette's and MCMC (Monte Carlo calculations and Matrix Computations), using Monte Carlo simulations performed with TOPAS and MCNP6.1. To generate the SOBPs, algorithms were developed for implementation of the two methods, which enabled to find the weights for thirty variations of SOBPs, categorized according to their width and maximum depths. The MCMC method used weight optimization in designing SOBPs to avoid negative values. In contrast, the Bortfeld/Jette's method yielded the SOBPs according to the variation of a power-law parameter ( ) introduced by the range-energy relationship. Optimal values of , from MCNP and TOPAS, were selected in order to retrieve SOBPs with the best smoothness and then related to those obtained from the literature. In comparing both methods and codes, dose homogeneity parameters ( ) were used to examine the SOBP flatness and gamma analyses were employed to assess the dose deposition along its full extension. The results showed that the SOBPs designed using the MCMC method had better values and computational performance for both codes when compared to the Bortfeld/Jette's method. The gamma analyses highlighted significant differences between the entrance doses comparing the two different methods, for SOBPs with intermediate and high depths and small width. This evaluation was not possible with the values alone, which stresses the relevance of a broad analysis to avoid unintended doses in healthy tissues.Artigo IPEN-doc 29884 New insights in phenothiazinium-mediated photodynamic inactivation of candida auris2023 - SILVA, ABDENEGO R.; CABRAL, FERNANDA V.; SILVA, CAMILA R.; SILVA, DANIELA F.T.; FREITAS, ANDERSON Z.; FONTES, ADRIANA; RIBEIRO, MARTHA S.n recent years, Candida auris has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against C. auris. To evaluate the photoinactivation of yeasts, we quantified colony-forming units and monitored ROS production. To gain some insights into the differences between MB and DMMB, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm). After, we verified the effectiveness of DMMB against biofilms by measuring metabolic activity and biomass, and the structures were analyzed through scanning electron microscopy and optical coherence tomography. We also evaluated the cytotoxicity in mammalian cells. DMMB-PDI successfully eradicated C. auris yeasts at 3 μM regardless of the light dose. In contrast, MB (100 μM) killed cells only when exposed to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to inhibit biofilm formation and destroy mature biofilms, with no observed toxicity in fibroblasts. We conclude that DMMB-PDI holds great potential to combat the global threat posed by C. auris. © 2023 by the authors.Artigo IPEN-doc 29066 Responses of melanoma cells to photobiomodulation depend on cell pigmentation and light parameters2022 - CONTATORI, CAROLINA G. de S.; SILVA, CAMILA R.; PEREIRA, SAULO de T.; RODRIGUES, MARIA F.S.D.; LUNA, ARTHUR C. de L.; MARQUES, MARCIA M.; RIBEIRO, MARTHA S.Melanoma is a highly aggressive skin cancer that requires new approaches for its management. Low-level laser therapy, currently named photobiomodulation therapy (PBM), has been used to improve different conditions but its effects and safe use on melanoma remain unexplored. Herein, we investigated the PBM impact on melanoma cells differing by pigmentation using near-infrared (NIR) and red lasers in vitro. In vivo, we evaluated the effects of the red laser on melanoma-bearing mice. Amelanotic (SK-MEL-37) and melanotic (B16F10) cells were exposed in vitro to a NIR (780 nm, 40 mW) or a red laser (660 nm, 40 mW) in 3 different light doses: 30, 90, and 150 J/cm2 and responses were assessed regarding mitochondrial activity, invasiveness, migration, and VEGF production. In vivo, melanoma-bearing mice received the red laser delivering 150 J/cm2 directly to the tumor on 3 consecutive days. Mice were monitored for 15 days regarding tumor progression and mouse survival. We noticed that amelanotic cells were unresponsive to NIR light. In contrast, NIR irradiation at 30 J/cm2 promoted an increase in the invasiveness of pigmented cells, even though all light doses have inhibited cell migration. Regarding the red laser on pigmented cells, the highest light dose (150 J/cm2) decreased the VEGF production and migration. In vivo, melanoma-bearing mice treated with red laser showed smaller tumor volume and longer survival than controls. We conclude that PBM appears to be safe for amelanotic non-pigmented melanoma but triggers different responses in melanotic pigmented cells depending on light parameters. Additionally, a high dose of red laser impairs the invasive behavior of melanoma cells, probably due to the decrease in VEGF synthesis, which may have contributed to tumor arrest and increased mouse survival. These findings suggest that red laser therapy could be a new ally in the supportive care of melanoma patients.Artigo IPEN-doc 28357 Photobiomodulation therapy combined with radiotherapy in the treatment of triple-negative breast cancer-bearing mice2021 - SILVA, CAMILA R.; SALVEGO, CAMILA de A.; ROSTELATO, MARIA E.; ZEITUNI, CARLOS A.; RIBEIRO, MARTHA S.This work investigated the effect of photobiomodulation therapy (PBM) combined with radiotherapy (RT) on triple-negative breast cancer (TNBC)-bearing mice. Female BALB/c mice received 4 T1 cells into a mammary fat pad. Local RT was performed with a total dose of 60 Gy divided into 4 consecutive sessions of 15 Gy. For PBM, a red laser was used in three different protocols: i-) single exposure delivering 150 J.cm−2 (24 h after the last RT session), and ii-) radiant exposure of 150 J.cm−2 or iii-) fractionated radiant exposure of 37.5 J.cm−2 (after each RT session). Tumor volume, complete blood cell count, clinical condition, metastasis, and survival of animals were monitored during 3 weeks post-RT. Our results demonstrated that regardless of the protocol, PBM arrested the tumor growth, improved the clinical condition, and prevented hemolytic anemia. Besides, although PBM groups have exhibited a high neutrophil:lymphocyte ratio (NLR), they decreased the number of lung metastases and enhanced mouse survival. Worthy of note, PBM should be used along with the RT sessions in higher radiant exposures, since PBM at 150 J.cm−2 per session significantly extended the survival rate. Together, these data suggest PBM could be a potential ally to RT to fight TNBC.Artigo IPEN-doc 27834 Safety and clinical impact of a single red light irradiation on breast tumor-bearing mice2021 - PEREIRA, SAULO T.; SILVA, CAMILA R.; NUNEZ, SILVIA C.; RIBEIRO, MARTHA S.Low-level light therapy has been used in health care as a therapeutic strategy for different diseases. However, its effects on cancer are controversial. This work evaluated the effects of three energies on breast cancer-bearing mice after a single red light-emitting diode (LED) irradiation. 4T1 cells were inoculated into the mammary fat pad of female BALB/c mice. When tumor volume reached 100 mm3, animals were irradiated by a LED irradiator (660 ± 11 nm) with energies of 1.2, 3.6, and 6.0 J. Control without irradiation and healthy animals were also evaluated. Mice were monitored regarding tumor volume and total blood count. After euthanasia, their organs were examined. We observed that a single irradiation does not increase tumor volume. All irradiated groups exhibited better clinical conditions than control, which presented a significant decrease in platelet and red blood cell levels compared with healthy mice. The energy of 3.6 J arrested neutrophil-lymphocyte rate besides promoting longer survival and a lower number of metastatic nodules in the lungs. These findings suggest that a single red LED irradiation causes no impact on the course of the disease. Besides, the intermediary dose-effect should be further investigated since it seems to promote better outcomes on breast cancer-bearing mice.Artigo IPEN-doc 27369 Development of a shielding device for radiotherapy of breast cancer-bearing mice2020 - SILVA, C.R.; PEREIRA, S.T.; NAPOLITANO, C.M.; SOMESSARI, E.S.R.; RIBEIRO, M.S.Breast cancer is the fifth most common cause of death worldwide. Currently, one of the standard treatments for breast cancer is radiation therapy (RT). On the other hand, mouse models have been used in pre-clinical studies for breast cancer RT, requiring dedicated shielding to exposure the breast region. In this work, we considered the values of the lead attenuation coefficient and the material tenth reducing layer for 60Co gamma radiation and developed a lead shielding device for breast cancer-bearing mice to be exposed to localized breast RT. Five-kg of lead were heated to of 340ºC and inserted into an aluminum mold previously adjusted to the dimensions of the device. After solidification, the device was shaped into a cylinder with dimension of 14 x 15 x 7 cm (height x width x thickness, respectively). A round cut-out for breast exposure of 1 cm in diameter was made at 5 cm from the basis of the device. For shielding device validation, we performed calibrations to establish a dose of 10 Gy to the target volume. Fifteen CaSO4:Dy thermoluminescent dosimeters were distributed inside the conical tube to mimic the mouse position inside the shielding. The shielding device was placed at a fixed distance of 10 cm from the target for optimal exposure time. After irradiation, the dosimeters were read using a thermoluminescent reader. According to our results, we were able to develop a body-shielding device that assured the required dose for RT of breast cancer in mice.Artigo IPEN-doc 26934 Efeito da terapia fotodinâmica no tratamento de leishmaniose cutânea em um modelo murino2016 - CABRAL, FERNANDA V.; SILVA, CAMILA R.; SAUTER, ISMAEL P.; SABINO, CAETANO P.; YOSHIMURA, TANIA M.; CORTEZ, MAURO; RIBEIRO, MARTHA S.Leishmanioses são doenças parasitárias desenvolvidas por protozoários do gênero Leishmania. A forma cutânea abrange lesões destrutivas e ulceradas com diversas limitações no tratamento. Terapias alternativas são fundamentais devido à grande relevância da doença e elevada incidência. Nesse contexto, a terapia fotodinâmica (PDT) tem sido introduzida devido ao baixo custo, baixa toxicidade, praticidade e sem relatos de resistência na literatura. Neste trabalho, dezesseis camundongos BALB/c foram infectados com 1.106 parasitos de Leishmania(L) amazonensisno membro posterior esquerdo e acompanhados por 4 semanas até o surgimento da lesão. Após esse período, os animais foram submetidos à PDT usando um diodo emissor de luz (λ=660 ±22 nm) e azul de metileno (100 μM), com fluências de 50, 100 e 150J/cm² e acompanhados durante 3 semanas. Animais controle não receberam tratamento. O tamanho da lesão e escala de dor foram mensurados utilizando um paquímetro e filamentos von Frey, respectivamente. A quantificação da carga parasitária foi realizada através do método de diluição limitante. Os resultados demonstraram que, nas semanas 2 e 3 após tratamento, ocorreu diminuição da lesão e alívio de dor nos animais que receberam 150J/cm², sugerindo que a PDT promoveu melhora clínica através da modulação do processo inflamatório.Artigo IPEN-doc 25800 Natural anthraquinones as novel photosentizers for antiparasitic photodynamic inactivation2019 - DIMMER, JESICA; CABRAL, FERNANDA V.; SABINO, CAETANO P.; SILVA, CAMILA R.; NUNEZ-MONTOYA, SUSANA C.; CABRERA, JOSE L.; RIBEIRO, MARTHA S.Background: Cutaneous leishmaniasis (CL) is a vector-borne disease caused by obligate protist parasites from the genus Leishmania. The potential toxicity as well as the increased resistance of standard treatments has encouraged the development of new therapeutical strategies. Photodynamic inactivation (PDI) combines the use of a photosensitizer and light to generate reactive oxygen species and kill cells, including microorganisms. Vegetal kingdom constitutes an important source of bioactive compounds that deserve to be investigated in the search of naturally occurring drugs with leishmanicidal activity. Purpose: The purpose of this study was to test the antiparasitic activity of PDI (ApPDI) of five natural anthraquinones (AQs) obtained from Heterophyllaea lycioides (Rusby) Sandwith (Rubiacae). To support our results, effect of AQ mediated-PDI on parasite´s morphology and AQ uptake were studied. Cytotoxicity on fibroblasts was also evaluated. Study design/Methods: Two monomers, soranjidiol (Sor) and 5-chlorosoranjidiol (5-ClSor) plus three bi-anthraquinones (bi-AQs), bisoranjidiol (Bisor), 7-chlorobisoranjidiol (7-ClBisor) and Lycionine (Lyc) were selected for this study. Recombinant L. amazonensis promastigote strain expressing luciferase was subjected to AQs and LED treatment. Following irradiation with variable light parameters, cell viability was quantified by bioluminescence. Alteration on parasite's morphology was analyzed by scanning electron microscopy (SEM). In addition, we verified the AQ uptake in Leishmania cells by fluorescence and their toxicity on fibroblasts by using MTT assay. Results: Bisor, Sor and 5-ClSor exhibited photodynamic effect on L. amazonensis. SEM showed that promastigotes treated with Bisor-mediated PDI exhibited a significant alteration in shape and size. Sor and 5-ClSor presented higher uptake levels than bi-AQs (Bisor, Lyc and 7-ClBisor). Finally, Sor and Bisor presented the lowest toxic activity against fibroblasts. Conclusion: Taking together, our results indicate that Sor presents the highest specificity towards Leishmania cells with no toxicity on fibroblasts.Artigo IPEN-doc 23565 Exploring the effects of low-level laser therapy on fibroblasts and tumor cells following gamma radiation exposure2016 - SILVA, CAMILA R.; CABRAL, FERNANDA V.; CAMARGO, CLAUDINEI F.M. de; NUNEZ, SILVIA C.; YOSHIMURA, TANIA M.; LUNA, ARTHUR C. de L.; MARIA, DURVANEI A.; RIBEIRO, MARTHA S.Ionizing radiation (IR) induces DNA damage and low-level laser therapy (LLLT) has been investigated to prevent or repair detrimental outcomes resulting from IR exposure. Few in vitro studies, however, explore the biological mechanisms underlying those LLLT benefits. Thus, in this work, fibroblasts and tumor cells are submitted to IR with doses of 2.5 Gy and 10 Gy. After twenty-four-h, the cells are exposed to LLLT with fluences of 30 J cm–2, 90 J cm–2, and 150 J cm–2. Cellular viability, cell cycle phases, cell proliferation index and senescence are evaluated on days 1 and 4 after LLLT irradiation. For fibroblasts, LLLT promotes – in a fluence-dependent manner – increments in cell viability and proliferation, while a reduction in the senescence was observed. Regarding tumor cells, no influences of LLLT on cell viability are noticed. Whereas LLLT enhances cell populations in S and G2/M cell cycle phases for both cellular lines, a decrease in proliferation and increase in senescence was verified only for tumor cells. Putting together, the results suggest that fibroblasts and tumor cells present different responses to LLLT following exposure to gamma-radiation, and these promising results should stimulate further investigations. Senescence of tumor cells and fibroblasts on the 4th day after ionizing radiation (IR) and low-level laser therapy (LLLT) exposures. The number of senescent cells increased significantly for tumor cells (a) while for fibroblasts no increment was observed (b). The blue collor indicates senescence activity.Artigo IPEN-doc 21672 Exploring light-based technology for wound healing and appliance distribution2015 - RIBEIRO, MARTHA S.; NUNEZ, SILVIA C.; SABINO, CAETANO P.; YOSHIMURA, TANIA M.; SILVA, CAMILA R.; NOGUEIRA, GESSE E.C.; SUZUKI, HIDEO; GARCEZ, AGUINALDO S.