Página 9 dos resultados de 2289 itens digitais encontrados em 0.008 segundos

Photodynamic Therapy Can Be Effective as a Treatment for Herpes Simplex Labialis

MAROTTI, Juliana; ARANHA, Ana Cecilia Correa; EDUARDO, Carlos De Paula; RIBEIRO, Martha Simoes
Fonte: MARY ANN LIEBERT INC Publicador: MARY ANN LIEBERT INC
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.58736%
Background Data and Objective: Herpes is a common infectious disease that is caused by human herpesviruses. Several treatments have been proposed, but none of them prevent reactivation of the virus. This article describes the use of photodynamic therapy (PDT) as a treatment for herpes lesions, and reports on four cases. Materials and Methods: PDT was used as an adjuvant therapy for the treatment of herpes labialis in four patients. A special type of 0.01% (m/V) of methylene blue solution was applied to the vesicular stage of herpesviral disease and the lesions were irradiated with laser energy (wavelength 660 nm, energy density 120 J/cm(2), output power of 40 mW, 2 min per point, 4.8 J of energy/point, at four points). After 24 h the patients returned and phototherapy was repeated with the same equipment, this time with 3.8 J/cm(2) and 15 mW, for a total dose of 0.6 J. The same procedure was repeated 72 h and 1 wk later. Results: Treatment with low-level laser therapy can be considered as an option in the treatment of herpes labialis, and decreases the frequency of vesicle recurrence and provides comfort for patients. No significant acute side effects were noted and the lesions healed rapidly. Conclusion: Treatment of herpes labialis with PDT was effective...

Photosensitizer-Loaded Magnetic Nanoemulsion for Use in Synergic Photodynamic and Magnetohyperthermia Therapies of Neoplastic Cells

PRIMO, Fernando L.; RODRIGUES, Marcilene M. A.; SIMIONI, Andreza Ribeiro; LACAVA, Zulmira G. M.; MORAIS, Paulo C.; TEDESCO, Antonio C.
Fonte: AMER SCIENTIFIC PUBLISHERS Publicador: AMER SCIENTIFIC PUBLISHERS
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.72437%
In this study a magnetic nanoemulsion (MNE) was developed from a mixture of two components, namely biodegradable surfactants and biocompatible citrate-coated cobalt ferrite-based magnetic fluid, for entrapment of Zn(II)-Phthalocyanine (ZnPc), the latter a classical photosensitizer (PS) species used in photodynamic therapy (PDT) procedures. The sample`s stability was evaluated as a function of time using photocorrelation spectroscopy (PCS) for determination of the average hydrodynamic diameter, diameter dispersion and zeta potential. The ZnPc-loaded magneto nanoemulstion (ZnPc/MNE) formulation was evaluated in vitro assays to access the phototoxicity and the effect of application of AC magnetic fields (magnetohyperthermia damage) after incubation with J774-A1 macrophages cells. Darkness toxicity, phototoxicity and AC magnetic field exposures revealed an enhancement response for combined photodynamic and magnetohyperthermia (MHT) processes, indicating the presence of the synergic effect.; MCT/CNPq; FAPESP[06/50562-1]; FAPESP[04/00860-0]

Photodynamic therapy in periocular basal cell carcinoma: Case report

Carneiro, Rachel Camargo; Santiago de Macedo, Erick Marcet; de Lima, Patricia Picciarelli; Matayoshi, Suzana
Fonte: SOC BRASILEIRA OFTALMOLOGIA; RIO DE JANEIRO Publicador: SOC BRASILEIRA OFTALMOLOGIA; RIO DE JANEIRO
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
57.766187%
The authors report the use of photodynamic therapy with methyl aminolevulinate (Metvix (R)) in a patient with nodular and infiltrative basal cell carcinoma in the right lower eyelid. Side effects on the eye were evaluated weekly. After 12 weeks of treatment, to confirm cure the patient was submitted to a 2-mm punch biopsy, the anatomopathological findings of which were negative for neoplasia. Photodynamic therapy with methyl aminolevulinate was shown to be an attractive alternative to surgical excision(-)the current gold standard treatment worldwide.

Comparison of Photodynamic Therapy versus conventional antifungal therapy for the treatment of denture stomatitis: a randomized clinical trial

Mima, E. G.; Vergani, C. E.; Machado, A. L.; Massucato, E. M. S.; Colombo, A. L.; Bagnato, Vanderlei Salvador; Pavarina, A. C.
Fonte: WILEY-BLACKWELL; HOBOKEN Publicador: WILEY-BLACKWELL; HOBOKEN
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.766187%
Clin Microbiol Infect 2012; 18: E380E388 Abstract In this randomized clinical trial, the clinical and mycological efficacy of Photodynamic Therapy (PDT) was compared with that of topical antifungal therapy for the treatment of denture stomatitis (DS) and the prevalence of Candida species was identified. Patients were randomly assigned to one of two groups (n = 20 each); in the nystatin (NYT) group patients received topical treatment with nystatin (100 000 IU) four times daily for 15 days and in the PDT group the denture and palate of patients were sprayed with 500 mg/L of Photogem (R), and after 30 min of incubation, were illuminated by light emitting-diode light at 455 nm (37.5 and 122 J/cm2, respectively) three times a week for 15 days. Mycological cultures taken from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15) and at the follow-up time intervals (days 30, 60 and 90). Colonies were quantified (CFU/mL) and identified by biochemical tests. Data were analysed by Fishers exact test, analysis of variance and Tukey tests and ? test (a = 0.05). Both treatments significantly reduced the CFU/mL at the end of the treatments and on day 30 of the follow-up period (p <0.05). The NYT and PDT groups showed clinical success rates of 53% and 45%...

Photodynamic therapy for the treatment of induced mammary tumor in rats

Ferreira, Isabelle; Ferreira, Juliana; Vollet Filho, José Dirceu; Moriyama, Lilian Tan; Bagnato, Vanderlei Salvador; Salvadori, Daisy Maria Favero; Rocha, Noeme S.
Fonte: Springer; London Publicador: Springer; London
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.54077%
The objective of this work was to evaluate photodynamic therapy (PDT) by using a hematoporphyrin derivative as a photosensitizer and light-emitting diodes (LEDs) as light source in induced mammary tumors of Sprague–Dawley (SD) rats. Twenty SD rats with mammary tumors induced by DMBAwere used. Animals were divided into four groups: control (G1), PDT only (G2), surgical removal of tumor (G3), and submitted to PDT immediately after surgical removal of tumor (G4). Tumors were measured over 6 weeks. Lesions and surgical were LEDs lighted up (200 J/cm2 dose). The light distribution in vivo study used two additional animals without mammary tumors. In the control group, the average growth of tumor diameter was approximately 0.40 cm/week. While for PDT group, a growth of less than 0.15 cm/week was observed, suggesting significant delay in tumor growth. Therefore, only partial irradiation of the tumors occurred with a reduction in development, but without elimination. Animals in G4 had no tumor recurrence during the 12 weeks, after chemical induction, when compared with G3 animals that showed 60 % recurrence rate after 12 weeks of chemical induction. PDT used in the experimental model of mammary tumor as a single therapy was effective in reducing tumor development...

Avaliação da resposta fotodinâmica em fígado normal de ratos utilizando fonte de luz pulsada no regime de femtossegundos; Evaluation of photodynamic response in normal rat liver using a femtosecond regime pulsed irradiation

Grecco, Clovis
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/02/2009 PT
Relevância na Pesquisa
57.72437%
A terapia fotodinâmica (TFD) é uma promissora técnica para o tratamento de câncer e de outras patologias. O tratamento baseia-se na ação de uma fonte de luz com o agente fotossensibilizador (FS) e o oxigênio molecular presente nas células, gerando espécies reativas de oxigênio que causam a morte celular. Uma das limitações atuais da técnica é a penetração da luz no tecido biológico. Entre os fotossensibilizadores mais empregados, estão os derivados de hematoporfirina, que são excitados da região do vermelho do espectro eletromagnético. Fotossensibilizadores vêm sendo desenvolvidos para iluminação com comprimentos de onda maiores, com o potencial de aumentar a profundidade de penetração e em conseqüência, o volume tecidual tratado. Outra opção para aumentar o volume tecidual de resposta utilizando derivados de hematoporfirina é a utilização de fontes de luz pulsada que, em comparação com a contínua, vem apresentado resultados significativos no estudo da TFD. Neste estudo, foi realizada a fotodegradação in vitro do fotossensibilizador comercial Photogem® (Moscou, Rússia) com tempos variando entre 0 e 40 minutos. Como fonte de luz contínua foi utilizado um laser de diodo (Eagle Heron Quantum Tech...

Porfirinas tetracatiônicas alquiladas: sistemas porfirínicos fotossensibilizadores para uso em terapia fotodinâmica do câncer de pele; Tetracationic alkylated porphyrin: Photosensitizers for use in photodynamic therapy of skin cancers

Pavani, Christiane
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/05/2009 PT
Relevância na Pesquisa
57.585654%
Uma série de porfirinas meso-substituídas tetracatiônicas foi sintetizada e caracterizada, com o objetivo de estudar o papel da anfifilicidade e a presença de zinco em propriedades que podem influenciar na eficácia dos mesmos como FSs na terapia fotodinâmica. Observamos que as propriedades fotofísicas dos compostos são semelhantes (máximos de absorção na mesma região, red. quantico fl0,02; rend. quantico ox. singlete ~0.8). O aumento na lipofilicidade e a presença de zinco no centro do anel porfirínico aumentam a incorporação dos FSs em vesículas e células, uma vez que a presença de zinco possibilita a coordenação pelos grupos fosfato dos fosfolipídeos (os resultados os estudos das monocamadas de Langmuir e dos filmes de Langmuir-Blodgett corroboram com esta afirmação). A incorporação em mitocôndrias é também dependente da lipofilicidade do FS e é influenciada pelo potencial eletroquímico de membrana. A presença do zinco mostrou diminuir a incorporação em mitocôndrias isoladas e em mitocôndrias nas células HeLa, devido às características particulares da membrana mitocondrial interna. A fototoxicidade aumenta proporcionalmente ao aumento da eficiência da incorporação em membranas, que é atribuída às interações favoráveis entre os FSs e as membranas...

Inativação dos micro-organismos causadores da onicomicose por terapia fotodinâmica - estudo in vitro e clínico; Photodynamic inactivation of micro-organisms causing onychomycosis - clinical and in vitro study

Silva, Ana Paula da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 20/02/2013 PT
Relevância na Pesquisa
57.585654%
A onicomicose é a mais frequente das doenças ungueais, pode ser causada por dermatófitos, leveduras e fungos não-dermatófitos. A infecção caracteriza-se por unhas quebradiças, espessadas e despigmentadas ou com excesso de pigmentação. O tratamento convencional consiste na administração sistêmica de antifúngicos e antibióticos por longos períodos, podendo ser o responsável pelo aumento de linhagens microbianas resistentes às drogas disponíveis. Esse fator associado a alta incidência deste tipo de infecção na população tornam importante o desenvolvimento de novas tecnologias e opções terapêuticas. Esta dissertação está composta por duas partes: pesquisa básica (estudos in vitro) e aplicada (estudo clínico), além do desenvolvimento de equipamento para o tratamento da onicomicose por Terapia Fotodinâmica (TFD). A TFD consiste no emprego do fotossensibilizador (FS) ativado por luz em comprimento de onda adequado que, na presença de oxigênio, produz espécies reativas de oxigênio tóxicas que inativam as células alvo (fungos e bactérias). Nos ensaios in vitro, utilizamos um dos principais fungos causadores da onicomicose, o Trychophyton mentagrophytes e dois fotossensibilizadores diferentes: Solução de curcuminóides (PDTPharma Ltda....

Treatment of Experimental Periodontal Disease by Photodynamic Therapy in Rats With Diabetes

Almeida, Juliano Milanezi; Theodoro, Letícia Helena; Bosco, Alvaro Francisco; Nagata, Maria José Hitomi; Bonfante, Samara; Garcia, Valdir Gouveia
Fonte: Amer Acad Periodontology Publicador: Amer Acad Periodontology
Tipo: Artigo de Revista Científica Formato: 2156-2165
ENG
Relevância na Pesquisa
57.585654%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Background: The aim of this study was to evaluate histologically and histometrically the influence of photodynamic therapy (PDT) as an adjuvant treatment on induced periodontitis in rats with diabetes.Methods: Two hundred forty rats were divided evenly into two groups: non-diabetic (ND; n = 120) and alloxan diabetic (D; n = 120). Periodontal disease was induced in both groups at the first mandibular molar. After 7 days, the ligature was removed, and all animals underwent scaling and root planing (SRP) and were divided according to the following treatments: irrigation with saline solution (SRP); irrigation with a phenothiazinium dye (100 mu g/ml) (TBO); laser irradiation (660 nm, 24 J) (LLLT); and PDT (TBO and laser irradiation). Ten animals in each experimental group and treatment subgroup were euthanized at 7, 15, and 30 days. The histometric values were analyzed statistically (P<0.05).Results: In the ND group, the animals treated by PDT showed less bone loss (0.33 +/- 0.05 mm(2), 0.35 +/- 0.06 mm(2), and 0.27 +/- 0.07 mm(2) at 7, 15, and 30 days, respectively; P<0.05) at all experimental periods than the SRP group (1.11 +/- 0.11 mm(2)...

Comparison of Photodynamic Therapy versus conventional antifungal therapy for the treatment of denture stomatitis: a randomized clinical trial

Mima, E. G.; Vergani, Carlos Eduardo; Machado, A. L.; Massucato, Elaine Maria Sgavioli; Colombo, A. L.; Bagnato, V. S.; Pavarina, A. C.
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: E380-E388
ENG
Relevância na Pesquisa
57.766187%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Processo FAPESP: 05/02193-4; Processo FAPESP: 05/03226-3; Processo FAPESP: 10/01212-3; Clin Microbiol Infect 2012; 18: E380E388 Abstract In this randomized clinical trial, the clinical and mycological efficacy of Photodynamic Therapy (PDT) was compared with that of topical antifungal therapy for the treatment of denture stomatitis (DS) and the prevalence of Candida species was identified. Patients were randomly assigned to one of two groups (n = 20 each); in the nystatin (NYT) group patients received topical treatment with nystatin (100 000 IU) four times daily for 15 days and in the PDT group the denture and palate of patients were sprayed with 500 mg/L of Photogem (R), and after 30 min of incubation, were illuminated by light emitting-diode light at 455 nm (37.5 and 122 J/cm2, respectively) three times a week for 15 days. Mycological cultures taken from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15) and at the follow-up time intervals (days 30, 60 and 90). Colonies were quantified (CFU/mL) and identified by biochemical tests. Data were analysed by Fishers exact test, analysis of variance and Tukey tests and ? test (a = 0.05). Both treatments significantly reduced the CFU/mL at the end of the treatments and on day 30 of the follow-up period (p <0.05). The NYT and PDT groups showed clinical success rates of 53% and 45%...

Photodynamic and Antibiotic Therapy Impair the Pathogenesis of Enterococcus faecium in a Whole Animal Insect Model

Chibebe Junior, José; Fuchs, Beth B.; Sabino, Caetano P.; Junqueira, Juliana Campos; Jorge, Antonio O. C.; Ribeiro, Martha S.; Gilmore, Michael S.; Rice, Louis B.; Tegos, George P.; Hamblin, Michael R.; Mylonakis, Eleftherios
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.81278%
Enterococcus faecium has emerged as one of the most important pathogens in healthcare-associated infections worldwide due to its intrinsic and acquired resistance to many antibiotics, including vancomycin. Antimicrobial photodynamic therapy (aPDT) is an alternative therapeutic platform that is currently under investigation for the control and treatment of infections. PDT is based on the use of photoactive dye molecules, widely known as photosensitizer (PS). PS, upon irradiation with visible light, produces reactive oxygen species that can destroy lipids and proteins causing cell death. We employed Galleria mellonella (the greater wax moth) caterpillar fatally infected with E. faecium to develop an invertebrate host model system that can be used to study the antimicrobial PDT (alone or combined with antibiotics). In the establishment of infection by E. faecium in G. mellonella, we found that the G. mellonella death rate was dependent on the number of bacterial cells injected into the insect hemocoel and all E. faecium strains tested were capable of infecting and killing G. mellonella. Antibiotic treatment with ampicillin, gentamicin or the combination of ampicillin and gentamicin prolonged caterpillar survival infected by E. faecium (P = 0.0003...

Photodynamic Therapy for Pododermatitis in Penguins

Sellera, Fabio Parra; Sabino, Caetano Padial; Ribeiro, Martha Simoes; Fernandes, Lorie Tukamoto; Pogliani, Fabio Celidonio; Teixeira, Carlos Roberto; Pereira Dutra, Gustavo Henrique; Nascimento, Cristiane Lassalvia
Fonte: Wiley-Blackwell Publicador: Wiley-Blackwell
Tipo: Artigo de Revista Científica Formato: 353-356
ENG
Relevância na Pesquisa
57.585654%
Pododermatitis is currently one of most frequent and important clinical complications in seabirds kept in captivity or in rehabilitation centers. In this study, five Magellanic penguins with previous pododermatitis lesions on their footpad were treated with photodynamic therapy (PDT). All PDT treated lesions successfully regressed and no recurrence was observed during the 6-month follow-up period. PDT seems to be an inexpensive and effective alternative treatment for pododermatitis in Magellanic penguins encouraging further research on this topic. (C) 2014 Wiley Periodicals, Inc.

Preparação e avaliação de nanoesferas de PLGA (50:50) contendo porfirinas anfifílicas para uso em terapia fotodinâmica; Preparation and evaluation of PLGA (50:50) nanoespheres containing amphiphilic porphyrins to be used in photodynamic therapy

Juliana Machado da Silveira Alves
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/06/2010 PT
Relevância na Pesquisa
57.72437%
As porfirinas 5,10,15,20(3-hidroxifenil)porfirina (m-THPP), 5-hexil-10,20-bis(3hidrofenil)porfirina (hex-m-bisHPP) e 5-hexil-10,15,20-tris(3-hidroxifenil)porfirina (hex-m-triHPP), têm o mesmo rendimento quântico de oxigênio singleto e foram encapsuladas em nanopartículas (NPs) poli(láctico-co-glicólico) (PLGA) 50:50, preparadas através do método de emulsão e evaporação. As NPs obtidas têm diâmetros médios na faixa de submicrometros (<240 nm) e pequena dispersividade. O potencial zeta medido mostrou uma pequena variação (de -21.6 mV a -19.3 mV). A porcentagem de encapsulação das porfirinas obtidas foram: 93 ± 2; 97 ± 2 and 69 ± 1 para m-THPP, hex-m-bisHPP e hex-m-triHPP respectivamente. A eficácia fotodinâmica e a internalização das porfirinas foi investigada a 37oC utilizando células humanas cancerígenas de próstata (LNCaP). Após 2 horas de incubação com as NPs contendo a porfirina as porcentagens de internalização celular foram iguais para todas as porfirinas. As três porfirinas causam morte celular e dão a mesma viabilidade quando se varia o tempo de incubação (30-120 min), concentração da porfirina (2,5 a 7,5 mmol L) e dose de luz incidente (33 a 99 J cm). Análise das células por microscopia confocal mostrou que as porfirinas encapsuladas nas NPs foram localizadas no citoplasma...

Evaluation of the photodynamic activity of Xanthene Dyes on Artemia salina described by chemometric approaches

Pellosi,Diogo S.; Batistela,Vagner R.; Souza,Vagner R. de; Scarminio,Ieda S.; Caetano,Wilker; Hioka,Noboru
Fonte: Academia Brasileira de Ciências Publicador: Academia Brasileira de Ciências
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2013 EN
Relevância na Pesquisa
57.72437%
The development of drugs for photodynamic therapy (PDT) is an important area of research due to their growing use in medical applications. Therefore, it is important to develop new bioassay methods for PDT photosensitizers that are inexpensive, easy to handle and highly sensitive to environmental conditions. Xanthene dyes (fluorescein, rose bengal B, erythrosine B and eosin Y) with LED light sources were investigated using Artemia salina as a bioindicator of photodynamic activity. In this study, three factors were investigated: (i) photosensitizers concentration, (ii) the LED irradiation time and (iii) the waiting time between the addition of the photosensitizers and the beginning of the irradiation. To analyze the photo-killing of A. salina, it was employed a 23 full factorial design. The death of A. salina was related to dye structure and the interaction between the irradiation time and the photosensitizers concentration. About 60% of crustaceans death was obtained using rose bengal B, which presentes the highest quantum yield of singlet oxygen due to the number of iodide substituents in the xanthenes ring. The proposed bioassay using A. salina, xanthene dyes and LED irradiation was found suitable for quantitative PDT drug evaluation.

Assessment of Leishmania major and Leishmania braziliensis promastigote viability after photodynamic treatment with aluminum phthalocyanine tetrasulfonate (AlPcS4)

JG,Pinto; CP,Soares; J,Mittmann
Fonte: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP Publicador: Centro de Estudos de Venenos e Animais Peçonhentos - CEVAP, Universidade Estadual Paulista - UNESP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
57.585654%
Cutaneous leishmaniasis is an infectious disease caused by protozoans of the genus Leishmania, which is transmitted through the bite of hematophagous insects of the genus Lutzomyia. This study aimed at testing in vitro the phototoxic effect of aluminum phthalocyanine tetrasulfonate (AlPcS4) on the viability of Leishmania major and Leishmania braziliensis. Stationary phase promastigote forms were treated with AlPcS4 at 1.0 µM and 10.0 µM and incubated for one hour. Then 659 nm laser was applied at 5 and 10 J/cm². Parasite viability was determined by differential count using the trypan blue dye exclusion method and by monitoring growth curves for nine days. Trypan blue exclusion assay showed a significant reduction of viable parasites compared to controls, L. major seemed more sensitive to the toxic effects of AlPcS4 in the dark. The most effective photodynamic therapy (PDT) was obtained with AlPcS4 at 10.0 µM and 10 J/cm² whereas L. braziliensis showed the highest mortality rate after treatment.

Photodynamic diagnosis model for depth evaluation of basal cell carcinomas

Salas García, Irene; Fanjul Vélez, Félix; Ortega Quijano, Noé; Arce Diego, José Luis
Fonte: The Optical Society (OSA) Publicador: The Optical Society (OSA)
Tipo: info:eu-repo/semantics/conferenceObject; publishedVersion
ENG
Relevância na Pesquisa
57.585654%
The present work is devoted to the development of a diagnostic model based on photodynamic therapy to obtain an estimation of a skin tumor depth from the measurement of the photosensitizer fluorescence emission.

Curcumin-mediated photodynamic inactivation of Candida albicans in a murine model of oral candidiasis

Dovigo, Livia Nordi; Carmello, Juliana Cabrini; Costa, Carlos Alberto de Souza; Vergani, Carlos Eduardo; Brunetti, Iguatemy Lourenco; Bagnato, Vanderlei Salvador; Pavarina, Ana Claudia
Fonte: Informa Healthcare; London Publicador: Informa Healthcare; London
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
57.585654%
In vitro investigations of curcumin-mediated photodynamic therapy (PDT) are encouraging, but there is a lack of reliable in vivo evidence of its efficacy. This study describes the photoinactivation of Candida albicans in a murine model of oral candidiasis, using curcumin as a photosensitizer. Forty immunosuppressed mice were orally inoculated with C. albicans and after five days, they received topical curcumin (20, 40 and 80 µ M) and illumination with LED light. The use of curcumin or light alone were also investigated. Positive control animals did not receive any treatment and negative control animals were not inoculated with C. albicans. The number of surviving yeast cells was determined and analyzed by ANOVA and Tukey's post-hoc test (α = 0.05). Histological evaluation of the presence of yeast and inflammatory reaction was also conducted. All exposures to curcumin with LED light caused a significant reduction in C. albicans viability after PDT, but the use of 80 mu M curcumin associated with light was able to induce the highest log 10 reduction in colony counts (4 logs). It was concluded that curcumin-mediated PDT proved to be effective for in vivo inactivation of C. albicans without harming the host tissue of mice.; FAPESP (08/03994-9...

Photodynamic Effects of Zinc(II) Phthalocyanine-Loaded Polymeric Micelles in Human Nasopharynx KB Carcinoma Cells

Garcia Vior, María Cecilia; Marino, Julieta; Roguin, Leonor Patricia; Sosnik, Alejandro Dario; Awruch, Josefina
Fonte: Wiley Publicador: Wiley
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
Relevância na Pesquisa
57.72437%
A major difficulty in photodynamic therapy is the poor solubility of the photosensitizer (PS) under physiological conditions which correlates with low bioavailability. PS aggregation leads to a decrease in the photodynamic efficiency and a more limited activity in vitro and in vivo. To improve the aqueous solubility and reduce the aggregation of 2,9(10),16(17),23(24)-tetrakis[(2-dimethylamino)ethylsulfanyl] phthal-ocyaninatozinc(II) (Pc9), the encapsulation into four poloxamine polymeric micelles (T304, T904, T1107 and T1307) displaying a broad spectrum of molecular weight and hydrophilic–lipophilic balance was investigated. The aqueous solubility of Pc9 was increased up to 30 times. Morphological evaluation showed the formation of Pc9-loaded spherical micelles in the nanosize range. UV/Vis and fluorescence studies indicated that Pc9 is less aggregated upon encapsulation in comparison with Pc9 in water–DMSO 2% and remained photostable. Pc9-loaded micelles generated singlet molecular oxygen in high yields. Photocytotoxicity assays using human nasopharynx KB carcinoma cells confirmed that the encapsulation of Pc9 in T1107 and T1307 increases its photocytotoxicity by 10 times in comparison with the free form in water–DMSO. In addition...

Efeitos da terapia fotodinâmica e de uma única aplicação de laser de baixa potência em bactérias in vitro; Effects of photodynamic therapy and of a sole low-power laser irradiation on bacteria in vitro

Benvindo, Rogério Gubert; Braun, Graziela; Carvalho, Alberito Rodrigo de; Bertolini, Gladson Ricardo Flor
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2008 POR
Relevância na Pesquisa
57.58736%
O laser de baixa potência vem sendo usado para acelerar a cicatrização em úlceras de pressão devido a seus efeitos cicatrizante, antiinflamatório, antiedematoso e analgésico. No entanto, não há consenso quanto a seu efeito em úlceras infectadas. O objetivo deste estudo foi verificar o efeito bactericida da laserterapia e da terapia fotodinâmica (TFD) com laser de baixa potência, InGaP, 670 nm, em doses de 2, 4 e 6 J/cm², em bactérias gram-positivas e gram-negativas in vitro. Foram preparadas 32 placas de Petri com bactérias, 16 com Pseudomonas aeruginosa e 16 com Staphilococcus aureus. Aleatoriamente dividiu-se cada grupo em oito subgrupos (duas placas cada): três subgrupos tratados só com laserterapia, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; três subgrupos tratados com TFD, em doses de 2 J/cm², 4 J/cm² e 6 J/cm²; um tratado apenas com fotossensibilizante (azul de metileno a 0,1 µg/ml); e um subgrupo não tratado (controle). Os subgrupos laser e TFD foram irradiados uma única vez e incubados por 24 horas. Os outros dois subgrupos não receberam irradiação. As culturas foram analisadas visualmente para verificação ou não do halo de inibição. Em todos os subgrupos, de ambas as bactérias, não foi observado qualquer halo de inibição nem de crescimento. Conclui-se que a terapia a laser e a fotodinâmica de baixa potência (InGaP...

Synthesis and Photodynamic Activity of 5,10,15-Tris(p-chlorophenyl)-20-(2-hydroxy-3-methoxyphenyl)-21H,23H-porphyrin

Arredondo-Espinoza,Eder; López-Cortina,Susana; Balderas-Rentería,Isaías
Fonte: Sociedad Química de México A.C. Publicador: Sociedad Química de México A.C.
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
57.585654%
Photodynamic therapy (PDT) is an effective option for the treatment of solid neoplastic tumors, as well as non-malignant diseases such as dermatological, ophthalmological and benign pathologies. PDT destroys cancer cells by photochemical generation of reactive oxygen species upon absorption of visible light by a photosensitizing agent (PS). Here, we describe the synthesis and characterization of the unsymmetrical A3B porphyrin 5,10,15-Tris(p-chlorophenyl)-20-(2-hydroxy-3-methoxyphenyl)-21H,23H-porphyrin, which presents different groups at the meso positions, p-chloro-phenyl and 2-hydroxy-3-methoxyphenyl and is a novel target molecule in order to evaluate the synergistic effect of these hydrophobic and hydrophilic moieties distributed unsymmetrically on the porphyrin macrocycle. We demonstrated the in vitro cytotoxic effect of the synthesized porphyrin, by the WST-1 assay on a cultured human cervical adenocarcinoma cell line (HeLa ATCC: CCL-2), as well as the presence of apoptosis by T.U.N.E.L. assay. We compared the phototoxicity and intrinsic cytotoxicity of the PS and found a considerable difference in the IC50 between phototoxic activity (1.5 μM) and intrinsic cytotoxicity (7 μM). The results of the induction of apoptosis on HeLa cells treated with the unsymmetrical porphyrin at a final concentration of 80 µM showed 15% apoptotic cells...