RESUMO
BACKGROUND AND OBJECTIVE: Vibrational spectroscopic methods associated with multivariate statistical techniques have been succeeded in discriminating skin lesions from normal tissues. However, there is no study exploring the potential of these techniques to assess the alterations promoted by photodynamic effect in tissue. The present study aims to demonstrate the ability of Fourier Transform Infrared (FTIR) spectroscopy on Attenuated total reflection (ATR) sampling mode associated with principal component-linear discriminant analysis (PC-LDA) to evaluate the biochemical changes caused by photodynamic therapy (PDT) in skin neoplastic tissue. MATERIALS AND METHODS: Cutaneous neoplastic lesions, precursors of squamous cell carcinoma (SCC), were chemically induced in Swiss mice and submitted to a single session of 5-aminolevulinic acid (ALA)-mediated PDT. Tissue sections with 5 µm thickness were obtained from formalin-fixed paraffin-embedded (FFPE) and processed prior to the histopathological analysis and spectroscopic measurements. Spectra were collected in mid-infrared region using a FTIR spectrometer on ATR sampling mode. Principal Component-Linear Discriminant Analysis (PC-LDA) was applied on preprocessed second derivatives spectra. Biochemical changes were assessed using PCA-loadings and accuracy of classification was obtained from PC-LDA . RESULTS: Sub-bands of Amide I (1,624 and 1,650 cm(-1) ) and Amide II (1,517 cm(-1) ) indicated a protein overexpression in non-treated and post-PDT neoplastic tissue compared with healthy skin, as well as a decrease in collagen fibers (1,204, 1,236, 1,282, and 1,338 cm(-1) ) and glycogen (1,028, 1,082, and 1,151 cm(-1) ) content. Photosensitized neoplastic tissue revealed shifted peak position and decreased ß-sheet secondary structure of proteins (1,624 cm(-1) ) amount in comparison to non-treated neoplastic lesions. PC-LDA score plots discriminated non-treated neoplastic skin spectra from post-PDT cutaneous lesions with accuracy of 92.8%, whereas non-treated neoplastic skin was discriminated from healthy tissue with 93.5% accuracy and post-PDT cutaneous lesions was discriminated from healthy tissue with 89.7% accuracy. CONCLUSION: PC-LDA was able to discriminate ATR-FTIR spectra of non-treated and post-PDT neoplastic lesions, as well as from healthy skin. Thus, the method can be used for early diagnosis of premalignant skin lesions, as well as to evaluate the response to photodynamic treatment. Lasers Surg. Med. 48:538-545, 2016. © 2016 Wiley Periodicals, Inc.
Assuntos
Ácido Aminolevulínico/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Neoplasias Cutâneas/tratamento farmacológico , Pele/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Ácido Aminolevulínico/uso terapêutico , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Análise Discriminante , Feminino , Camundongos , Fármacos Fotossensibilizantes/uso terapêutico , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Análise de Componente Principal , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologiaRESUMO
Background: Rice is globally one of the most important food crops, and NaCl stress is a key factor reducing rice yield. Amelioration of NaCl stress was assessed by determining the growth of rice seedlings treated with culture supernatants containing 5-aminolevulinic acid (ALA) secreted by strains of Rhodopseudomonas palustris (TN114 and PP803) and compared to the effects of synthetic ALA (positive control) and no ALA content (negative control). Results: The relative root growth of rice seedlings was determined under NaCl stress (50 mM NaCl), after 21 d of pretreatment. Pretreatments with 1 μM commercial ALA and 10X diluted culture supernatant of strain TN114 (2.57 μM ALA) gave significantly better growth than 10X diluted PP803 supernatant (2.11 μM ALA). Rice growth measured by dry weight under NaCl stress ordered the pretreatments as: commercial ALA N TN114 N PP803 N negative control. NaCl stress strongly decreased total chlorophyll of the plants that correlated with non-photochemical quenching of fluorescence (NPQ). The salt stress also strongly increased hydrogen peroxide (H2O2) concentration in NaCl-stressed plants. The pretreatments were ordered by reduction in H2O2 content under NaCl stress as: commercial ALA N TN114 N PP803 N negative control. The ALA pretreatments incurred remarkable increases of total chlorophyll and antioxidative activities of catalase (CAT), ascorbate peroxide (APx), glutathione reductase (GR) and superoxide dismutase (SOD); under NaCl stress commercial ALA and TN114 had generally stronger effects than PP803. Conclusions: The strain TN114 has potential as a plant growth stimulating bacterium that might enhance rice growth in saline paddy fields at a lower cost than commercial ALA.
Assuntos
Rodopseudomonas , Oryza/crescimento & desenvolvimento , Oryza/enzimologia , Ácido Aminolevulínico/metabolismo , Antioxidantes , Fotossíntese , Estresse Fisiológico , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Clorofila/análise , Produtos Agrícolas , Plântula , Transporte de Elétrons , Salinidade , Ascorbato Peroxidases/metabolismo , Fluorescência , Glutationa Redutase/metabolismoRESUMO
Introducción: La terapia fotodinámica (TFD) con ácido 5-aminolevulínico (ALA) y metil aminolevulinato (MAL) ha mostrado utilidad en el manejo del acné inflamatorio. Métodos: Dos grupos de cuatro pacientes cada uno, portadores de acné inflamatorio leve o moderado. Se realizaron dos sesiones de TFD separadas por dos semanas: un grupo fue tratado con MAL y luz roja y el otro, con ALA y luz azul. Se midió la severidad del acné con escala de 6 puntos y se consideró éxito clínico los grados 0 y 1. Resultados: En ambos grupos se observó éxito clínico a las 12 semanas post tratamiento, quedando con pigmentación residual, escasos comedones y menos de 10 pápulas. Se observaron efectos adversos tolerables, siendo los más importantes el eritema y la descamación. Conclusión: La TFD con ALA y MAL es una buena alternativa terapéutica para aquellos pacientes con acné inflamatorio leve y moderado que no responden o tienen contraindicación a los tratamientos convencionales.
Introduction: Photodynamic therapy with methyl aminolevulinate (MAL) and 5-aminolevulinic acid (ALA) has shown to be useful in the management of inflammatory acne. Methods: Two groups of 4 patients each with mild to moderate inflammatory acne. Two PDT sessions were performed within a 2 week interval; one group was treated with MAL and red light, and the other with ALA and blue light. Acne severity was measured with a 6-point scale and clinical success was considered between grades 0 and 1. Results: In both groups, clinical success was observed at 12 weeks post treatment, leaving residual pigmentation, scarce comedones and less than 10 papules. Tolerable side effects were observed, being the most important erythema and desquamation. Conclusion: PDT with ALA and MAL is a good therapeutic option for patients with mild to moderate inflammatory acne who do not respond or have contraindications to conventional treatments.