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El estilo de vida de las sociedades actuales involucra el empleo intenso de pantallas a LED. La radiación luminosa que emana de estos dispositivos posee alto contenido espectral en una región identificada como fototóxica (aproximadamente 380- 500 nm). La exposición a este tipo de radiación es en parte responsable del “estrés ocular digital” y de la alteración de los ritmos circadianos. Frente a esta situación se han sugerido un conjunto de medidas preventivas y paliativas, entre ellas el empleo de anteojos con capacidad para filtrar luz fototóxica. El presente trabajo compila, en lengua española, información relevante sobre la problemática y, mediante el uso de distancias Euclídeas, como criterio para diferenciar espectros, presenta y discute la performance de distintas lentes disponibles en el mercado con el objetivo de brindar información orientativa sobre su potencial efectividad. Se analizaron lentes transparentes y pigmentadas específicas (publicitadas como protectoras de exceso de luz azul) y pigmentadas no específicas (bajo costo). Nuestros resultados muestran que las lentes transparentes específicas ensayadas no presentan un grado de atenuación significativo en la región fototóxica. Por su parte, las lentes pigmentadas específicas poseen, en general, una muy buena atenuación mientras que las no específicas poseen una moderada capacidad de atenuación., The lifestyle of today's societies involves the intensive use of LED screens. The light radiation emanating from these devices has a high spectral content in a region identified as phototoxic (approximately 380- 500 nm). Exposure to this type of radiation is in part responsible for “digital eye strain” and the alteration of circadian rhythms. Faced with this situation, a set of preventive and palliative measures have been suggested, among them, the use of glasses with the ability to filter phototoxic light. The present work compiles, in Spanish language, relevant information on the problematic involved and, by employing Euclidean distances as criterion to differentiate spectra, presents and discusses the performance of different lenses available in the market in order to provide information as guidance on their potential effectiveness. Specific pigmented and transparent lenses (advertised as protective against excess of blue light) and non-specific pigmented (low cost) lenses were analyzed. Our results show that the specific transparent lenses tested do not present a significant degree of attenuation in the phototoxic region. On the other hand, the specific pigmented lenses generally have a very good attenuation while the non-specific ones have a moderate attenuation capacity., Centro de Investigaciones Ópticas

Background Small-diameter, myelinated axons are selectively susceptible to dysfunction in several inflammatory PNS and CNS diseases, resulting in pain and degeneration, but the mechanism is not known. Methods We used in vivo confocal microscopy to compare the effects of inflammation in experimental autoimmune neuritis (EAN), a model of Guillain-Barré syndrome (GBS), on mitochondrial function and transport in large- and small-diameter axons. We have compared mitochondrial function and transport in vivo in (i) healthy axons, (ii) axons affected by experimental autoimmune neuritis, and (iii) axons in which mitochondria were focally damaged by laser induced photo-toxicity. Results Mitochondria affected by inflammation or laser damage became depolarized, fragmented, and immobile. Importantly, the loss of functional mitochondria was accompanied by an increase in the number of mitochondria transported towards, and into, the damaged area, perhaps compensating for loss of ATP and allowing buffering of the likely excessive Ca2+ concentration. In large-diameter axons, healthy mitochondria were found to move into the damaged area bypassing the dysfunctional mitochondria, re-populating the damaged segment of the axon. However, in small-diameter axons, the depolarized mitochondria appeared to “plug” the axon, obstructing, sometimes completely, the incoming (mainly anterograde) transport of mitochondria. Over time (~ 2 h), the transported, functional mitochondria accumulated at the obstruction, and the distal part of the small-diameter axons became depleted of functional mitochondria. Conclusions The data show that neuroinflammation, in common with photo-toxic damage, induces depolarization and fragmentation of axonal mitochondria, which remain immobile at the site of damage. The damaged, immobile mitochondria can “plug” myelinated, small-diameter axons so that successful mitochondrial transport is prevented, depleting the distal axon of functioning mitochondria. Our observations may explain the selective vulnerability of small-diameter axons to dysfunction and degeneration in a number of neurodegenerative and neuroinflammatory disorders. Electronic supplementary material The online version of this article (10.1186/s12974-018-1094-8) contains supplementary material, which is available to authorized users.