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  1. Início
  2. Pesquisar por Assunto

Navegando por Assunto "Photodynamic therapy"

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    Action of Photodynamic Therapy at Low Fluence in 9 L/lacZ Cells after Interaction with Chlorins
    (MDPI) Vitorio, Gabrielle dos Santos; Godoi, Bruno Henrique; Pinto, Juliana Guerra; Ferreira, Isabelle; Pacheco Soares, Cristina; Ferreira-Strixino, Juliana
    Gliosarcoma (GS) is a primary malignant neoplasm of the central nervous system, treated with an unfavorable prognosis with surgery, radiotherapy, and chemotherapy. The treatment for GS consists of surgical resection, almost always accompanied by radiotherapy and/or chemotherapy, given the invasive behavior of the tumor. Photodynamic Therapy (PDT) is studied as an alternative method that combines light, a photosensitizer (PS), and molecular oxygen. This study aimed to compare the effects of PDT using the photosensitizers Fotoenticine (FTC) and Photodithazine (PDZ) at low concentrations and fluences. For this study, 9 L/lacZ cells, concentrations of 1.55 µg mL−1 , 12.5 µg mL−1 , and 50 µg mL−1 of chlorins and fluences of 1, 5, and 10 J/cm2 were used. A test was also carried out with Trypan Blue in L929 cells at the mentioned concentrations at 5 J/cm2 . Both chlorins were internalized in the cytoplasm, with a significant reduction in viability (>95%) in almost all groups and altered cell adhesion and morphology after PDT. HSP70 expression decreased in both PS, while HSP27 increased only in PDT with FTC, and although there was a change in cell adhesion in the 9 L/LacZ lineage it was not observed in the L929 fibroblast lineage. Both chlorins were effective, highlighting the concentration of 50 µg mL−1 at the fluence of 5 J/cm2 ; according to the present study, the PDZ showed better results.
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    Analysis of the effects of Photodynamic therapy with Photodithazine on the treatment of 9l/lacZ cells, in vitro study
    (Elsevier) Vitorio, Gabrielle dos Santos; Almeida, Rainara Moreno Sanches de; Pinto, Juliana Guerra; Fontana, Letícia Corrêa; Ferreira-Strixino, Juliana
    Gliosarcoma is an aggressive brain tumor. Photodynamic Therapy (PDT) is a treatment that can be used for various cancers of the CNS. The aim of this study was to analyze the effects of PDT with Photodithazine (PDZ) in the treatment of gliosarcoma, using 9 L/lacZ cells and serial concentrations of 200 μg/mL to 3.1 μg/mL of PDZ. The samples were divided into two groups: dark and light (10 J/cm2). The PDZ was internalized along all the cytoplasmic extension. Viability tests demonstrated a reduction in viable cells after PDT. The production of ROS was concentration-dependent and PDZ was found in mitochondria and lysosomes, presenting a discrete connection with α-tubulin. However, this structure is likely damaged, evidenced by changes in the morphological analysis. Thus, according to the parameters of this study, PDZ proved to be an interesting PS in PDT for the treatment of gliosarcoma, with the inherent limitations of an in vitro study.
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    Antimicrobial Effect of the Amniotic Membrane Isolated and Associated with Photodynamic Therapy
    (MDPI) Santos, Amanda Cerquearo Rodrigues dos; Teodoro, Guilherme Rodrigues; Ferreira-Strixino, Juliana; Sant’Anna, Luciana Barros
    Microbial control through alternative therapies, such as the amniotic membrane (AM) and antimicrobial photodynamic therapy (aPDT), has been gaining prominence with the advancement of bacterial resistance to conventional treatments. This study aimed to evaluate the antimicrobial effect of AM isolated and associated with aPDT using the PHTALOX® as a photosensitizer (PS) against Staphylococcus aureus and Pseudomonas aeruginosa biofilms. The groups studied were: C+; L; AM; AM+L; AM+PHTX; and AM+aPDT. The irradiation parameters were 660 nm, 50 J.cm−2, and 30 mW.cm−2. Two independent microbiological experiments were carried out in triplicate, and the results were analyzed by CFU/mL counting and a metabolic activity test, both statistically analyzed (p < 0.05). The integrity of the AM was verified after the treatments by a scanning electron microscope (SEM). The groups AM, AM+PHTX, and, mainly, AM+aPDT showed a statistical difference When compared to C+ regarding the decrease in CFU/mL and metabolic activity. SEM analysis showed significant morphological alterations in the AM+PHTX and AM+aPDT groups. The treatments with AM isolated or associated with PHTALOX® were adequate. The association had potentiated the biofilm effect, and the morphological differences presented by AM after treatment did not hinder its antimicrobial effect, encouraging its use in biofilm formation locals.
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    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 Campos
    Photodynamic 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.
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    Antimicrobial Photodynamic Therapy Mediated by Fotenticine and Methylene Blue on Planktonic Growth, Biofilms, and Burn Infections of Acinetobacter baumannii
    (MDPI) Figueiredo-Godoi, Lívia Mara Alves; Garcia, Maíra Terra; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Faustino, Eliseu Gabriel; Pedroso, Lara Luise Castro; Junqueira, Juliana Campos
    Antimicrobial photodynamic therapy (aPDT) is considered a promising alternative strategy to control Acinetobacter baumannii infections. In this study, we evaluated the action of aPDT mediated by a new photosensitizer derivative from chlorin e-6 (Fotoenticine—FTC) on A. baumannii, comparing its effects with methylene blue (MB). For this, aPDT was applied on A. baumannii in planktonic growth, biofilms, and burn infections in Galleria mellonella. The absorption of FTC and MB by bacterial cells was also evaluated using microscopic and spectrophotometric analysis. The results of planktonic cultures showed that aPDT reduced the number of viable cells compared to the non-treated group for the reference and multidrug-resistant A. baumannii strains. These reductions varied from 1.4 to 2 log10 CFU for FTC and from 2 log10 CFU to total inhibition for MB. In biofilms, aPDT with MB reduced 3.9 log10 CFU of A. baumannii, whereas FTC had no effect on the cell counts. In G. mellonella, only MB-mediated aPDT had antimicrobial activity on burn injuries, increasing the larvae survival by 35%. Both photosensitizers were internalized by bacterial cells, but MB showed a higher absorption compared to FTC. In conclusion, MB had greater efficacy than FTC as a photosensitizer in aPDT against A. baumannii.
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    Biochemical changes in Leishmania braziliensis after photodynamic therapy with methylene blue assessed by the Fourier transform infrared spectroscopy
    (Springer Nature Link) Sakane, Kumiko Koibuchi; Bhattacharjee, Tanmoy; Fagundes, Jaciara; Marcolino, Luciana Maria Cortez; Ferreira, Isabelle; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana
    Photodynamic therapy (PDT) with photosensitizer methylene blue was applied to Leishmania braziliensis, and Fourier transform infrared (FTIR) spectroscopy was used to study biochemical changes in the parasite after PDT in comparison to untreated (C), only irradiation (I), and only photosensitizer (PS). Spectral analysis suggests increase in lipids, proteins, and protein secondary structures in PDT compared with C and decrease in nucleic acids and carbohydrates. Interestingly, these trends are different from PDT of Leishmania major species, wherein lipids decrease; there are minimal changes in secondary structures and increase in nucleic acids and carbohydrates. The study thus suggests possibility of different biomolecular players/pathways in PDT-induced death of L. braziliensis and L. major.
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    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.
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    Effect of serial photodynamic therapy with curcumin on Leishmania braziliensis and Leishmania amazonensis promastigotes
    (CDRR Editors) Maciel, Lucas Tobias Rodrigues; Marcolino, Luciana Maria Cortez; Maciel, Fernanda Bueno Sant’Anna Pereira; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana
    Photodynamic Therapy (PDT) consists of using a light source and a photosensitive drug at an appropriate wavelength and molecular oxygen to trigger cell death through the production of reactive oxygen species. Because it is a localised therapy, PDT is shown to be ideal for skin diseases. American cutaneous Leishmaniasis (ACL) is a highly prevalent protozoan disease worldwide that presents different clinical evolutions and may result in ulcerations and disfiguring lesions on the skin and cartilage. This study was aimed at evaluating the effect in vitro of PDT applied serially using curcumin as a photosensitiser. For this, a concentration of 125 µg.mL-1 of curcumin was used on Leishmania braziliensis and Leishmania amazonensis strains, with a light fluence of 10 J.cm-2 and irradiance of 110 mW.cm-2. The tests done were viability analysis by trypan blue exclusion test, analysis of photosensitizer (PS) internalization by confocal microscopy and morphological alterations by May-Grunwald/Giemsa staining. We observed that there was internalisation of the PS before the first and second application of PDT, with L. braziliensis and L. amazonensis strains mortality of 92% and 82% respectively, after the second application, and induction of alterations in the structural conformation, such as cell size and non-evidence of nucleus and flagellum, demonstrating that PDT was effective. We conclude that serial PDT was effective in inducing the mortality of promastigotes forms of L. braziliensis and L. amazonensis in vitro, thus highlighting its potential for the treatment of leishmaniasis.
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    Effects of antimicrobial photodynamic therapy with photodithazine® on methicillin-resistant Staphylococcus aureus (MRSA): Studies in biofilms and experimental model with Galleria mellonella
    (Elsevier) Souza, Beatriz Müller Nunes; Miñán, Alejandro Guillermo; Brambilla, Isabelle Ribeiro; Pinto, Juliana Guerra; Garcia, Maíra Terra; Junqueira, Juliana Campos; Ferreira-Strixino, Juliana
    Staphylococcus aureus infections are a severe health problem due to the high mortality rate. Conventional treatment of these infections is via the administration of antibiotics. However, its indiscriminate use can select resistant microorganisms. Thus, it is necessary to develop alternatives for antibiotic therapy. Antimicrobial Photodynamic Therapy (aPDT), a therapeutic method that associates a photosensitizer (PS), a light source with adequate wavelength to the PS, interacts with molecular oxygen generating reactive oxygen species responsible for cell inactivation, is a viable alternative. This work aimed to analyze, in vitro and in vivo, the action of aPDT with PS Photodithazine® (PDZ) on the methicillin-resistant S. aureus (MRSA) strain. In the in vitro method, the S. aureus biofilm was incubated with PDZ at 50 and 75 μg.mL−1 for 15 min, adopting the light dose of 25, 50, and 100 J/cm2. In addition, PS interaction, formation of reactive oxygen species (ROS), bacterial metabolism, adhesion, bacterial viability, and biofilm structure were evaluated by scanning electron microscopy. Subsequently, the strain was inoculated into models of Galleria mellonella, and the survival curve, health scale, blood cell analysis, and CFU/mL of S. aureus in the hemolymph were analyzed after aPDT. In the in vitro results, bacterial reduction was observed in the different PDZ concentrations, highlighting the parameters of 75 μg.mL−1 of PDZ and 100 J/cm2. As for in vivo results, aPDT increased survival and stimulated the immune system of G. mellonella infected by S. aureus. aPDT proved effective in both models, demonstrating its potential as an alternative therapy in treating MRSA bacterial infections.
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    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 Ferreira
    Cutaneous 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.
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    Gelatin nanoparticles via template polymerization for drug delivery system to photoprocess application in cells
    (Taylor & Francis) Trindade, Agnes Cecheto; Castro, Pedro Augusto Rodrigues Ribeiro de; Pinto, Bruna Cristina dos Santos; Ambrósio, Jéssica Aparecida Ribeiro; Oliveira Junior, Benedito Marcio de; Beltrame Junior, Milton; Gonçalves, Erika Peterson; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Simioni, Andreza Ribeiro
    Photodynamic therapy (PDT) is a clinical treatment based on the activation of light-absorbing photosensitizers (PS) to generate reactive oxygen species, which are toxic to the targeted disease cells. Because most PS are hydrophobic with poor water solubility, it is necessary to encapsulate and solubilize PS in aqueous condi- tions to improve the photodynamic action for this compound. In this work, gelatin-poly(acrylic acid) nanoparticles (PAA/gelatin nanoparticles) via template polymerization for incorporation alu- minum chloride phthalocyanine (ClAlPc) as a model drug for PDT application were developed. Biocompatible core-shell polymeric nanoparticles were fabricated via template polymerization using gelatin and acrylic acid as a reaction system. The nanoparticulate system was studied by scanning electron microscopy, steady- state, and their biological activity was evaluated using in vitro cancer cell lines by classical MTT assay. The obtained nanopar- ticles had a spherical shape and DLS particle size were deter- mined further and was found to be around 170nm. The phthalocyanine-loaded-nanoparticles maintained their photophysi- cal behaviour after encapsulation. It is found that ClAlPc can be released from the nanoparticles in a sustained manner with a small initial burst release. In vitro cytotoxicity revealed that ClAlPc- loaded nanoparticles had similar cytotoxicity to free ClAlPc with mouse melanoma cancer cell line (B16-F10). In vitro photoeffects assay indicated that the nanoparticle formulation was superior in anticancer effect to free ClAlPc on mouse melanoma cancer cell line B16-F10. The results indicate that ClAlPc encapsulated in gel- atin-poly(acrylic acid) nanoparticles are a successful delivery sys- tem for improving photodynamic activity in the target tissue.
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    Hydroxyapatite microspheres used as a drug delivery system for gliosarcoma strain 9l/Lacz treatment by photodynamic therapy protocols
    (Elsevier) Ambrósio, Jéssica Aparecida Ribeiro; Marmo, Vitor Luca Moura; Gonçalves, Érika Peterson; Pinto, Juliana Guerra; Ferreira-Strixino, Juliana; Raniero, Leandro José; Beltrame Junior, Milton; Simioni, Andreza Ribeiro
    Background: Hydroxyapatite (HAp) presents similarities with the human bone structure and presents properties such as biodegradability, biocompatibility, and osteoconductivity, which favors its use in prostheses implants and enables its use as a vehicle for the delivery of photosensitizers (PS) from systems of release (DDS) for photodynamic therapy applications Methods: In this work was to synthesized hydroxyapatite microspheres (meHAp), encapsulated with chloroaluminium phthalocyanine (ClAlPc), for DDS. meHAp was synthesized using vaterite as a template. The drug was encapsulated by mixing meHAp and a 50.0 mg.mL− 1 ClAlPc solution. Photochemical, photophysical, and photobiological studies characterized the system. Results: The images from the SEM analysis showed the spherical form of the particles. All spectroscopic results showed excellent photophysical parameters of the drug studied when served in the meHAp system. The incorporation efficiency was 57.8 %. The trypan blue exclusion test results showed a significant reduction (p < 0.05) in cell viability for the groups treated with PDT at all concentrations above 250 μg.mL− 1 . In 9 L/lacZ gliosarcoma cells, PDT mediated at concentrations from 250 to 62.5 µg.mL− 1 reduced cell viability by more than 98 %. In the cell internalization study, it was possible to observe the internalization of phthalocyanines at 37 ◦C, with the accumulation of PS in the cytoplasm and inside the nucleus in the two tested concentrations. Conclusions: From all the results presented throughout the article, the meHAp system shows promise for use as a modified release system (DSD) in photodynamic therapy.
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    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, Cristina
    In 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.
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    Molecular effects of photodynamic therapy with curcumin on Leishmania major promastigotes
    (Parasitology Research, Springer-Verlag GmbH Germany) Marcolino, Luciana Maria Cortez; Pinto, Juliana Guerra; Ferreira, Isabelle; Godoi, Bruno Henrique; Canevari, Renata de Azevedo; Ferreira-Strixino, Juliana
    Leishmaniasis is a neglected disease mainly affecting low-income populations. Conventional treatment involves several side effects, is expensive, and, in addition, protozoa can develop resistance. Photodynamic therapy (PDT) is a promising alternative in treating the disease. PDT involves applying light at a specific wavelength to activate a photosensitive compound (photosensitizer, PS), to produce reactive oxygen species (ROS). Curcumin and its photochemical characteristics make it a good candidate for photodynamic therapy. Studies evaluating gene expression can help to understand the molecular events involved in the cell death caused by PDT. In the present study, RNA was extracted from promastigotes from the control and treated groups after applying PDT. RT-qPCR was performed to verify the expression of the putative ATPase beta subunit (ATPS), ATP synthase subunit A (F0F1), argininosuccinate synthase 1 (ASS), ATP-binding cassette subfamily G member 2 (ABCG2), glycoprotein 63 (GP63), superoxide dismutase (FeSODA), and glucose-6-phosphate dehydrogenase (G6PDH) genes (QR). The results suggest that PDT altered the expression of genes that participate in oxidative stress and cell death pathways, such as ATPS, FeSODA, and G6PD. The ATP-F0F1, ASS, and GP63 genes did not have their expression altered. However, it is essential to highlight that other genes may be involved in the molecular mechanisms of oxidative stress and, consequently, in the death of parasites.
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    PCR analysis of the effect of photodynamic therapy on breast tumors
    (CDRR Editors) Ferreira, Isabelle; Silva, Glenda Nicioli da; Ferreira-Strixino, Juliana; Grecco, Clovis; Bagnato, Vanderlei Salvador; Salvadori, Daisy Maria Favero; Pinto, Juliana Guerra; Rocha, Noeme Sousa
    Photodynamic therapy (PDT) is a promising therapeutic modality for treating cancer, including breast tumors. The oxidative damage caused by PDT culminates in cell death, induction of immune response, and the resulting destruction of the tumor. This study aimed to evaluate the gene expression profiling of genes BCL-2, BAX, and HER-2 and their proteins after PDT, associating it with the necrosis caused by this therapy under different fluences. Twenty-eight female rats received a single dose of 7,12-dimethylbenz (a) anthracene (DMBA - 80mg/kg), by gavage, for breast tumor induction. After the tumors grew, the animals were divided into four groups: G1 - control group – untreated breast tumor – and G2, G3, and G4 groups treated with PDT using Photogem@ as photosensitizer and interstitial irradiation, with fluences of 50J/cm, 100J/cm, and 150J/cm, respectively. Samples of tumors were harvested for histological examination by RT-qPCR. The RT-qPCR showed that the gene expression profiling of BCL-2, BAX, and HER-2 was not altered after PDT. Hemorrhagic necrosis and qualitatively greater vascular and cellular damage were observed and correlated positively with the fluence. PDT does not seem to induce the modulation of genes related to apoptosis. The results indicate that the type of cell death stimulated by PDT in breast tumor is necrosis.
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    Photodynamic Activity of Photogem® in Leishmania Promastigotes and Infected Macrophage
    (Taylor & Francis) Pinto, Juliana Guerra; Marcolino, Luciana Maria Cortez; Ferreira-Strixino, Juliana
    Objectives: This study aimed to evaluate the effect of photodynamic therapy (PDT) with Photogem⃝R in promastigotes of Leishmania braziliensis and Leishmania major, and in infected macrophages. Materials & methods: The following parameters were analyzed: Photogem⃝R internalization, mitochondrial activ- ity, viability, tubulin marking and morphological alterations in promastigotes and viability in infected macrophages. Results: Photogem⃝R accumulated in the cytosol and adhered to the flagellum. Changes were observed in the mitochondrial activity in groups maintained in the dark, with no viability alteration. After PDT, viability decreased up to 80%, and morphology was affected. Conclusion: The results point out that PDT with Photogem⃝R can reduce parasite and macrophage viability. Lay abstract: Cutaneous Leishmaniasis is a disease that can cause deforming lesions, the treatment of which is highly toxic. It is considered a neglected disease and little progress has been made in the treatment of this disease. Photodynamic therapy can be an alternative treatment which is less costly, and involves local treatment of the lesion, thereby reducing side effects for the patient. The present study aims to test the photodynamic therapy with Photogem, a photo sensitive drug, and to verify if the parasites can be affected by this therapy, aiming to apply this therapy in lesions in patients in the near future.
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    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.
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    Photodynamic therapy of cationic and anionic BSA-curcumin nanoparticles on amastigotes of Leishmania braziliensis and Leishmania major and Leishmania amazonensis
    (Photodiagnosis and Photodynamic Therapy, Elsevier) Marcolino, Luciana Maria Cortez; Ambrósio, Jéssica Aparecida Ribeiro; Pinto, Juliana Guerra; Ferreira, Isabelle; Simioni, Andreza Ribeiro; Ferreira-Strixino, Juliana
    Cutaneous leishmaniasis is a neglected disease prevalent in tropical countries, and conventional treatment can cause several serious side effects. Photodynamic therapy (PDT) can be considered a promising treatment alternative, as it is non-invasive therapy that has no side effects and uses accessible and low-cost substances, such as curcumin. This study evaluated the PDT response with cationic and anionic BSA nanoparticles encapsulated with curcumin in macrophages infected with L. braziliensis, L. major, and L. amazonensis. The nanoparticle system was characterized using a steady-state technique, scanning electron microscopy (SEM) study, and its biological activity was evaluated using macrophage cell lines infected with different Leishmania species. All spectroscopy measurements demonstrated that BSA curcumin (BSACur) has good photophysical properties, and confocal microscopy shows that macrophages and protozoa internalized the nanoparticles. The viability test demonstrated that at low concentrations, such as 0.1, 0.7, and 1.0 μmol. L 1, there was a decrease in cell viability after PDT application. Furthermore, a decrease in the number of parasites recovered was observed in the PDT groups. The results allowed us to conclude that curcumin loaded into BSA nanoparticles may have potential application in drug delivery systems for PDT protocols, demonstrating reduced cell viability at lower concentrations than free curcumin.
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    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.
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    Polyelectrolytic gelatin nanoparticles as a drug delivery system for the promastigote form of Leishmania amazonensis treatment
    (Taylor & Francis) Souza, Catarina de; Carvalho, Janicy Arantes; Abreu, Alexandro da Silva; Paiva, Lucas Prudente de; Ambrósio, Jéssica Aparecida Ribeiro; Beltrame Junior, Milton; Oliveira, Marco Antonio de; Mittmann, Josane; Simioni, Andreza Ribeiro
    In this study, phthalocianato[bis(dimethylaminoethanoxy)] silicon (NzPC) was loaded onto gelatin nanoparticles functionalized with polyelectrolytes (polystyrene sulfonate/polyallylamine hydrochlor- ide) by layer-by-layer (LbL) assembly for photodynamic therapy (PDT) application in promastigote form of Leishmania amazonensis treatment. The process yield, and encapsulation efficiency were 80.0% ± 1.8 and EE 1⁄4 87.0% ± 1.1, respectively. The polyelectro- lytic gelatin nanoparticles (PGN) had a mean diameter of 437.4±72.85nm, narrow distribution size with a polydispersity index of 0.086. The obvious switching of zeta potential indicates successful alternating deposition of the polyanion PSS and polyca- tion PAH directly on the gelatin nanoparticles. Photosensitizer photophysical properties were shown to be preserved after gel- atin nanoparticle encapsulation. The impact of the PDT in the via- bility and morphology of Leishmania amazonensis promastigote in culture medium was evaluated. The PGN-NzPc presented low tox- icity at the dark and the PDT was capable of decreasing the via- bility in more than 80% in 0.1mmol.L 1 concentration tested. The PDT also triggered significant morphological alterations in the Leishmania promastigotes. These results reinforce the idea that the use of PGN as photosensitizers carriers is useful for PDT of Leishmania promastigotes.
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