Resultados de Busca

Agora exibindo 1 - 3 de 3
  • 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, Juliana
    Photodynamic 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
    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, Juliana
    The 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
    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, Milton
    In 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.