hotodynamic inactivation of Streptococcus pneumoniae with external illumination at 808 nm through the ex vivo porcine thoracic cag

Autor(es)

Diaz Tovar, Johan Sebastian ^[1] ; Kassab, Giulia ^[1] ; Buzza, Hilde Harb ^[1] ; Bagnato, Vanderlei Salvador ^{[2, 1]} ; Kurachi, Cristina ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, Phys & Mat Sci Dept, Sao Carlos, SP - Brazil

^[2] Texas A&M Univ, College Stn, TX 77843 - USA

• Tipo de documento: Artigo Científico
• Fonte: Journal of Biophotonics; v. 15, n. 2 DEC 2021.
• Citações Web of Science: 0

Resumo

Pneumonia is responsible for high mortality rates around the world, and its major treatment is based on antibiotic treatment. Antimicrobial resistance has been increasing in the last years, resulting in relevant public health concern. A promising alternative for pneumonia is antimicrobial photodynamic therapy. The purpose of this study was to investigate whether 808 nm wavelength is able to be transmitted through the biological tissues of the thoracic wall and be delivered in enough energy inside the cage to activate indocyanine green and promote photodynamic response. A light source panel was developed composed of 200 lasers centered at 808 nm with an irradiance of 77.8 +/- 10.0 mW/cm(2) and tested in an ex vivo thoracic cage model. Monte Carlo simulations were used to understand the photon migration through all the tissues at the thoracic wall. It was observed that tissues responsible for the major absorption of photons are the skin and subcutaneous fat. Experimental measurement of the irradiance was obtained after the light pass-through ex vivo pig thoracic cage, obtaining 3% to 5% of the emitted irradiance. Finally, it was observed that even with 3% of the initial irradiance, a 99.9% reduction of the Streptococcus pneumoniae was successfully achieved after 42.6 minutes of irradiation. (AU)

• Processo FAPESP: 13/07276-1 - CEPOF - Centro de Pesquisa em Óptica e Fotônica
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 16/14033-6 - Estudos básicos da combinação dos efeitos fototérmico e fotodinâmico na aplicação de uma nova modalidade para o tratamento do Câncer
• Beneficiário: Hilde Harb Buzzá
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/50857-8 - INCT 2014 - de Óptica Básica e Aplicada às Ciências da Vida
• Beneficiário: Vanderlei Salvador Bagnato
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 18/18188-0 - Inativação fotodinâmica da Pneumonia Bacteriana utilizando nebulização do fotossensibilizador e iluminação extracorpórea
• Beneficiário: Giulia Kassab
• Modalidade de apoio: Bolsas no Brasil - Doutorado