Synergistic photocatalysis of a hydrochar/CeO2 composite for dye degradation under visible light.

The synthesis and characterization of a hydrochar/CeO2 composite along with its evaluation in methylene blue degradation under visible light are presented. The methodology consisted of a single-pass hydrothermal method, having as synthesis conditions 9 h of reaction time, 210 °C, autogenous pressure, and a biomass/CeO2 ratio of 100:1. The composite characterization revealed good dispersion of CeO2 in the carbonaceous matrix and significant synergy in the composite activation using visible irradiation. The photodegradation experiments showed an efficiency of 98% for white LED light, 91% for UV light, 96% for solar irradiation, and 85% for blue LED light using as conditions pH 7.0, 50 mg of composite, 50 mL of solution, 10 mg/L of dye initial concentration, and 120 min of contact time. Meanwhile, the reusability experiments evidenced a reuse capacity of up to five times with a constant photodegradation efficiency (99%); moreover, it was determined that the presence of electrolytes at pH below 7.0 during degradation negatively affected methylene blue degradation. Finally, the results of this work demonstrate that the hydrochar/CeO2 composite can be synthesized by a green method and used for the efficient treatment of water contaminated with methylene blue.

Delphinidins from Maqui Berry (Aristotelia chilensis) ameliorate the subcellular organelle damage induced by blue light exposure in murine photoreceptor-derived cells.

BACKGROUND: Blue light exposure is known to induce reactive oxygen species (ROS) production and increased endoplasmic reticulum stress, leading to apoptosis of photoreceptors. Maqui berry (Aristotelia chilensis) is a fruit enriched in anthocyanins, known for beneficial biological activities such as antioxidation. In this study, we investigated the effects of Maqui berry extract (MBE) and its constituents on the subcellular damage induced by blue light irradiation in mouse retina-derived 661W cells. METHODS: We evaluated the effects of MBE and its main delphinidins, delphinidin 3-O-sambubioside-5-O-glucoside (D3S5G) and delphinidin 3,5-O-diglucoside (D3G5G), on blue light-induced damage on retinal cell line 661W cells. We investigated cell death, the production of ROS, and changes in organelle morphology using fluorescence microscopy. The signaling pathway linked to stress response was evaluated by immunoblotting in the whole cell lysates or nuclear fractions. We also examined the effects of MBE and delphinidins against rotenone-induced mitochondrial dysfunction. RESULTS: Blue light-induced cell death, increased intracellular ROS generation and mitochondrial fragmentation, decreased ATP-production coupled respiration, caused lysosomal membrane permeabilization, and increased ATF4 protein level. Treatment with MBE and its main constituents, delphinidin 3-O-sambubioside-5-O-glucoside and delphinidin 3,5-O-diglucoside, prevented these defects. Furthermore, MBE and delphinidins also protected 661W cells from rotenone-induced cell death. CONCLUSIONS: Maqui berry may be a useful protective agent for photoreceptors against the oxidative damage induced by exposure to blue light.

Efeito crônico do LED de alta potência na retina de rato wistar / Chronic effect of high-power LED on Wistar rat retina

Introdução: O aumento da potência dos fotopolimerizadores à base de diodos emissores de luz (LED) contribuiu para a redução do tempo de fotopolimerização dos procedimentos restauradores e ortodônticos. Entretanto, é desconhecido o efeito do LED sobre a retina de quem faz o uso crônico desse equipamento sem usar filtros de proteção. Objetivo: Avaliar os possíveis efeitos do uso crônico de um aparelho fotopolimerizador LED de alta potência nas retinas de ratos Wistar. Material e métodos: Neste estudo experimental in vivo, seis ratos machos saudáveis foram utilizados. Os olhos esquerdos dos animais foram expostos à luz do fotopolimerizador à base de LED (Valo Ortho - Ultradent), a uma potência de 3.200mW/cm2 , por 144 segundos, à distância de 30cm, três vezes ao dia, durante 7 dias. Os olhos direitos foram cobertos com um tampão plástico removível preto, opaco, compondo a amostra controle. No oitavo dia, os animais foram anestesiados, submetidos à eutanásia, seus olhos foram dissecados e processados histologicamente. As lâminas foram digitalizadas utilizando-se uma câmera acoplada a um microscópico óptico e as suas imagens foram analisadas por histomorfometria bi e tridimensional. Resultados: Não foram encontradas diferenças intergrupos estatisticamente significativas para o volume total da retina (p=0,655) nem para o volume das camadas retinianas ganglionar (p=0,375), plexiforme interna (p=0,327), nuclear interna (p=0,693), plexiforme externa (p=0,177), nuclear externa (p=0,355) e o prolongamento de cones e bastonetes (p=0,871), quando avaliadas individualmente. As análises histomorfométricas bidimensionais apresentaram redução estatisticamente significativas (p<0,05) para as áreas celulares, com redução de 25,32% para a camada nuclear interna, 17,59% para a camada nuclear externa e 16,76% para a camada ganglionar. Apesar da densidade numérica das camadas nucleares interna e externa terem reduzido, e da camada ganglionar terem aumentado, as mesmas não apresentaram diferença estatisticamente significativas. Conclusão: A exposição crônica do LED de alta potência (3.200mW/cm2 ) induziu atrofia celular nas camadas nuclear interna, nuclear externa e ganglionar (AU).

Introduction: The increase in the power of light-emitting diode (LED) light cure has contributed to reduce the curing time of restorative and orthodontic procedures. However, the effect of the LED on the retina of those who make the chronic use of light units without using protection filters is unknown. Objective: To evaluate the possible effects of the chronic use of a high-power LED light curing device on the retinas of Wistar rats. Material and methods: In this experimental study in vivo, six healthy male rats were used and their ocular structures being the objects of study. The left eyes of the animals were exposed to high potency LED light, 3.200mW/cm2 (Valo Ortho - Ultradent), for 144 seconds at a distance of 30cm, three times a day, for 7 days. The right eyes were covered with removable plastic opaque tampon, composing the control sample. On the eighth day, the animals were anesthetized, euthanized, the eyes dissected and histologically processed. The slides were scanned using a camera coupled to an optical microscope and their images analyzed by two and three dimensional histomorphometry. Results: No statistically significant intergroup differences were found for total retinal volume (p = 0.655) or for the volume of the retinal layers ganglionic (p = 0.375), internal plexiform (p = 0.327), internal nuclear (p = 0.693), external plexiform (p = 0,177), external nuclear (p = 0.355) and the extension of cones and rods (p = 0.871), when evaluated individually. The histomorphometric analyzes presented statistically significant reduction for the cellular areas, with a reduction of 25,32% for the internal nuclear layer, 17,59% for external nuclear layer and 16,76% for ganglionic layer. Although the numerical density of the internal and external nuclear layers decreased, and the ganglion layer increased, they showed no statistically significant difference. Conclusion: Chronic exposure of the high-power LED (3.200mW/cm2 ) induced cellular atrophy in the internal nuclear layer, external nuclear layer and ganglionic layer (AU).

Caracterización del Insomnio en Lactantes a través de Actigrafía / Characterization of Insomnia In Infants through Actigraphy

Resumen. El Insomnio infantil definido como la dificultad mantenida, a pesar de la oportunidad y en función etaria, para iniciar o mantener el sueño o su calidad que provoca alteraciones funcionales en el niño y/o familia. Puede repercutir significativamente en la conducta, aprendizaje y metabolismo del niño y en su familia afectando su calidad de vida. La actigrafía nos permite a través de un dispositivo identificar periodos de vigilia y sueño. El objetivo de este trabajo es caracterizar a través de la actigrafía el patrón sueño-vigilia y evaluar la exposición a luz azul en niños menores de 2 años que consultan por insomnio. Se realizó un estudio observacional, descriptivo, transversal de lactantes derivados por insomnio al Centro de Sueño de Red de Salud UC Christus, durante: Marzo 2017-2018, con actigrafía. Fueron 20 actigrafías de 7 días. Edades entre 5 y 22 meses con diagnóstico de insomnio que no respondió al manejo inicial. 8 hombres, 12 mujeres. Horarios promedios: Acostarse: 20:31 hrs. Levantarse: 7:43 hrs. Horarios variables para acostarse: 15/20. 10/20 siestas después de las 16 hrs. Todos presentaron tiempo total de sueño disminuido, con aumentos del tiempo despierto una vez iniciado el sueño. Latencias del sueño aumentadas: 6/20. Eficiencia del sueño disminuidas en 4/20. Despertares nocturnos: promedio: 10.58. Expuestos a luz azul: 14/20. Horas exposición media: 2,4 hr/evento. Concluimos de este estudio que las principales dificultades fueron los despertares nocturnos con largos tiempo de vigilia, con disminución del tiempo total de sueño para la edad, y la actigrafía fue una herramienta de apoyo para objetivar conductas que dificultan la adquisición de un buen patrón de sueño.Palabras Clave: Insomnio infantil, sueño en lactantes, actigrafía, luz azul, despertares.

Abstract. Child insomnia is defined as sustained difficulty, despite the opportunity and according to age group, to initiate or maintain sleep, or a sleep quality causing that causes alterations in the child or family. It can significantly impact behavior, learning and metabolism of the child and his or her family, affecting their quality of life. The actigraphy through a device allows us to identify periods of wakefulness and sleep. The purpose of this work is to characterize sleep-wake patterns through actigraphy and to determine exposure to blue light in children younger than 2 years old, consulting for insomnia. An observational, descriptive, cross-sectional study of infants consulting for insomnia at the Sleep Center of UC Christus health network, in the period from March 2017 to 2018, with actigraphy. Twenty week long actigraphies were performed. The ages of the patients varied between 5 and 22 months, all had a diagnosis of insomnia that did not respond to initial management. Eight patients were male and 12 female. Hourly averages: bedtime: 8:31 PM. Waking up: 7:43 AM. Time variable for bedtime: 15/20. 10/20 NAPs after 16 hrs. All showed decreased sleep, with increases of total awake time once sleep began. Increased sleep latency: 6/20. Sleep efficiency decreased in 4/20. Nighttime Awakenings: average: 10.58. Exposed to blue light: 14/20. Average exposure in hours: 2.4 hr/event. We conclude from this study that the main difficulties were the nighttime awakenings with long time vigil, with decrease of the total sleep time for the age, and the actigraphy was a support tool to record behaviors that hinder a normal sleep pattern acquisition.Key words: Child insomnia, sleep in infants, actigraphy, blue light, awakenings

Efeitos da luz visível emitida por um aparelho fotopolimerizador sobre a pele do lábio, a córnea, a íris e a retina de coelhos da raça Nova Zelândia em vários tempos de exposição / Effects of visible light resin-curing over New Zealand rabbit's lip skin cornea, iris and retina following several times of exposure

O objetivo desta pesquisa "in vivo", foi estudar as possíveis alterações histopatológicas causadas, pela luz emitida por um aparelho fotopolimerizador, que apresenta um comprimento de onda oscilando entre 400 nm a 520 nm e uma intensidade de luz de 420 mW/cm2 a 600 mW/cm2. Foram utilizados 21 coelhos da raça Nova Zelândia, adultos que recebiam a exposição da luz azul encostado a pele do lábio ou a uma distância de 10 cm do olho. Os tempos de exposição variaram de doses unitária de 10 segundos até 30 minutos intercalados por dia durante 6 meses. Após os tempos estabelecidos para cada grupo, os animais eram anestesiados e sacrificados e tinham os segmentos da pele expostos e seus olhos submetidos à tramitação laboratorial de rotina para análise histológica. Os resultados obtidos através de comparações com os que não foram expostos à luz, mostraram que as estruturas analisadas, não sofreram alterações histológicas nestes períodos de exposição à luz

The aim of this "in vivo" research, was to study the possible histopathological changes caused by a light resin-curing with 420 to 600 mw/cm2 and 400 nm to 520 nm wave length. There were used 21 adult New Zealand rabbits, which were exposed to a blue light, either touching the lip skin or 10 cm far away from their eyes. The expouse time ranged from 10 sec. unitary dose till 30 minutes a day during 6 months. Once complete the exposition periods, the animals were anesthethyzed and sacrified, and had their exposed skin areas and eyes, submitted to histopathological routine analysis. The control group were not exposed to light. Based in our results, it was concluded that the analysed structures did not show any histopathological changes after the light exposure periods