Solar maculopathy secondary to sunlight exposure reflected from the screen of mobile devices: two case reports

Background Solar maculopathy is a well described clinical entity that usually occurs in patients that have gazed directly the sun. In this report we describe the first two cases of solar maculopathy in individuals exposed to sunlight reflected from the screen of mobile devices in the absence of direct sun gaze. Cases description Case 1. A 30-year-old Caucasic man presented with bilateral metamorphopsia, central scotoma and decreased visual acuity two days after being reading for four hours with his tablet computer in a terrace of a ski center. Case 2. A 20-year-old Caucasic woman was examined for bilateral decrease of visual acuity and central scotoma after being at the beach the day before and reading with her mobile phone for 3 hours. Both patients denied gazing directly to sunlight at any moment. In each case, exploration revealed fundus and OCT images compatible with the typical features of solar maculopathy. After 2 years of follow-up, in absence of any specific treatment, Case 1 had a complete resolution of the fundus alterations, while Case 2 still presented defects of the outer retinal layers. In both cases, an exposure to sunlight reflected from the screen of their mobile devices was documented in environments where solar radiation is thought to be augmented. Conclusion Sunlight reflection from a display screen needs to be considered as a possible risk factor for increased solar radiation and a subsequent risk of solar maculopathy

The mechanisms of potassium loss in acute myocardial ischemia: New insights from computational simulations

Acute myocardial ischemia induces hyperkalemia (accumulation of extracellular potassium), a major perpetrator of lethal reentrant ventricular arrhythmias. Despite considerable experimental efforts to explain this pathology in the last decades, the intimate mechanisms behind hyperkalemia remain partially unknown. In order to investigate these mechanisms, we developed a novel computational model of acute myocardial ischemia which couples a) an electrophysiologically detailed human cardiomyocyte model that incorporates modifications to account for ischemia-induced changes in transmembrane currents, with b) a model of cardiac tissue and extracellular K+ transport. The resulting model is able to reproduce and explain the triphasic time course of extracellular K+ concentration within the ischemic zone, with values of [K+]o close to 14 mmol/L in the central ischemic zone after 30 min. In addition, the formation of a [K+]o border zone of approximately 1.2 cm 15 min after the onset of ischemia is predicted by the model. Our results indicate that the primary rising phase of [K+]o is mainly due to the imbalance between K+ efflux, that increases slightly, and K+ influx, that follows a reduction of the NaK pump activity by more than 50%. The onset of the plateau phase is caused by the appearance of electrical alternans (a novel mechanism identified by the model), which cause an abrupt reduction in the K+ efflux. After the plateau, the secondary rising phase of [K+]o is caused by a subsequent imbalance between the K+ influx, which continues to decrease slowly, and the K+ efflux, which remains almost constant. Further, the study shows that the modulation of these mechanisms by the electrotonic coupling is the main responsible for the formation of the ischemic border zone in tissue, with K+ transport playing only a minor role. Finally, the results of the model indicate that the injury current established between the healthy and the altered tissue is not sufficient to depolarize non-ischemic cells within the healthy tissue

The mechanisms of potassium loss in acute myocardial ischemia: New insights from computational simulations

: Acute myocardial ischemia induces hyperkalemia (accumulation of extracellular potassium), a major perpetrator of lethal reentrant ventricular arrhythmias. Despite considerable experimental efforts to explain this pathology in the last decades, the intimate mechanisms behind hyperkalemia remain partially unknown. In order to investigate these mechanisms, we developed a novel computational model of acute myocardial ischemia which couples a) an electrophysiologically detailed human cardiomyocyte model that incorporates modifications to account for ischemia-induced changes in transmembrane currents, with b) a model of cardiac tissue and extracellular K + transport. The resulting model is able to reproduce and explain the triphasic time course of extracellular K + concentration within the ischemic zone, with values of [K+]o close to 14 mmol/L in the central ischemic zone after 30 min. In addition, the formation of a [K+]o border zone of approximately 1.2 cm 15 min after the onset of ischemia is predicted by the model. Our results indicate that the primary rising phase of [K+]o is mainly due to the imbalance between K + efflux, that increases slightly, and K + influx, that follows a reduction of the NaK pump activity by more than 50%. The onset of the plateau phase is caused by the appearance of electrical alternans (a novel mechanism identified by the model), which cause an abrupt reduction in the K + efflux. After the plateau, the secondary rising phase of [K+]o is caused by a subsequent imbalance between the K + influx, which continues to decrease slowly, and the K + efflux, which remains almost constant. Further, the study shows that the modulation of these mechanisms by the electrotonic coupling is the main responsible for the formation of the ischemic border zone in tissue, with K + transport playing only a minor role. Finally, the results of the model indicate that the injury current established between the healthy and the altered tissue is not sufficient to depolarize non-ischemic cells within the healthy tissue

Double fossilization in eukaryotic microorganisms from Lower Cretaceous amber

<p>Abstract</p> <p>Background</p> <p>Microfossils are not only useful for elucidating biological macro- and microevolution but also the biogeochemical history of our planet. Pyritization is the most important and extensive mode of preservation of animals and especially of plants. Entrapping in amber, a fossilized resin, is considered an alternative mode of biological preservation. For the first time, the internal organization of 114-million-year-old microfossils entrapped in Lower Cretaceous amber is described and analyzed, using adapted scanning electron microscopy in backscattered electron mode in association with energy dispersive X-ray spectroscopy microanalysis. Double fossilization of several protists included in diverse taxonomical groups and some vegetal debris is described and analyzed.</p> <p>Results</p> <p>In protists without an exoskeleton or shell (ciliates, naked amoebae, flagellates), determinate structures, including the nuclei, surface envelopes (cortex or cytoplasmic membrane) and hyaloplasm are the main sites of pyritization. In protists with a biomineralized skeleton (diatoms), silicon was replaced by pyrite. Permineralization was the main mode of pyritization. Framboidal, subhedral and microcrystalline are the predominant pyrite textures detected in the cells. Abundant pyritized vegetal debris have also been found inside the amber nuggets and the surrounding sediments. This vegetal debris usually contained numerous pyrite framboids and very densely packed polycrystalline pyrite formations infilled with different elements of the secondary xylem.</p> <p>Conclusion</p> <p>Embedding in amber and pyritization are not always alternative modes of biological preservation during geological times, but double fossilization is possible under certain environmental conditions. Pyritization in protists shows a quite different pattern with regard to plants, due to the different composition and cellular architecture in these microorganisms and organisms. Anaerobic sulphate-reducing bacteria could play a crucial role in this microbial fossilization.</p

Robustness of imageless electrocardiographic imaging against uncertainty in atrial morphology and location

[EN] Introduction: Electrocardiographic Imaging is a non-invasive technique that requires cardiac Imaging for the reconstruction of cardiac electrical activity. In this study, we explored imageless ECGI by quantifying the errors of using heart meshes with either an inaccurate location inside the thorax or an inaccurate geometry. Methods: Multiple-lead body surface recordings of 25 atrial fibrillation (AF) patients were recorded. Cardiac atrial meshes were obtained by segmentation of medical images obtained for each patient. ECGI was computed with each patient's segmented atrial mesh and compared with the ECGI obtained under errors in the atrial mesh used for ECGI estimation. We modeled both the uncertainty in the location of the atria inside the thorax by artificially translating the atria inside the thorax and the geometry of the atrial mesh by using an atrial mesh in a reference database. ECGI signals obtained with the actual meshes and the translated or estimated meshes were compared in terms of their correlation coefficients, relative difference measurement star, and errors in the dominant frequency (DF) estimation in epicardial nodes.Results: CC between ECGI signals obtained after translating the actual atrial meshes from the original position by 1 cm was above 0.97. CC between ECGIs obtained with patient specific atrial geometry and estimated atrial geometries was 0.93 +/- 0.11. Mean errors in DF estimation using an estimated atrial mesh were 7.6 +/- 5.9%.Conclusion: Imageless ECGI can provide a robust estimation of cardiac electrophysiological parameters such as activation rates even during complex arrhythmias. Furthermore, it can allow more widespread use of ECGI in clinical practice.This work was supported by: Instituto de Salud Carlos III, and Ministerio de Ciencia e Innovacion (supported by FEDER Fondo Europeo de Desarrollo Regional DIDIMO PLEC2021-007614, ESSENCE PID2020-119364RB-I00, and RYC2018-024346-I) , EIT Health (Activity code SAVE-COR 220385, EIT Health is supported by EIT, a body of the Eu-ropean Union) and Generalitat Valenciana Conselleria d'Educacio, Investigacio, Cultura i Esport (ACIF/2020/265) . The authors want to thank the organizers of the 2022 meeting of the International Society for Computerized Electrocardiology for their invitation to the meeting.Molero-Alabau, R.; González-Ascaso, A.; Climent, AM.; Guillem Sánchez, MS. (2023). Robustness of imageless electrocardiographic imaging against uncertainty in atrial morphology and location. Journal of Electrocardiology. 77:58-61. https://doi.org/10.1016/j.jelectrocard.2022.12.00758617

RENOVANDO EL MALETÍN DE FOL. Metodologías activas como herramientas innovadoras para el aprendizaje significativo del módulo de FOL

El sistema educativo debe ir de la mano de la continua transformación en la que vive inmersa la sociedad actual. Para ello es necesario contar con un profesorado comprometido con el aprendizaje, que otorgue gran importancia, tanto al diseño y organización de las actividades a desarrollar en el proceso de enseñanza-aprendizaje, como a la necesidad de fomentar en ese proceso la innovación e investigación educativa. Así, con el objetivo de lograr un aprendizaje significativo, las metodologías activas son las herramientas que se utilizan para convertir al alumnado en parte activa y protagonista, incrementado su motivación y logrando la adquisición de las competencias que necesita para su inserción y convivencia en el mundo laboral y social a lo largo de toda la vida.<br /

Himantormia lugubris, an Antarctic endemic on the edge of the lichen symbiosis

Himantormia lugubris is an Antarctic endemic with a distribution restricted to the northwest tip of Antarctic Peninsula, adjacent islands and South Georgia Island. In this region H. lugubris is an important component of the epilithic lichen community. The species has a fruticose thallus with usually simple and flattened branches whose grey surface is often disrupted exposing the black and dominant chondroid axis. Because the photobiont cells are mainly restricted to the patchy grey areas, positive carbon balance seems to be rather difficult for this species. Therefore, the aim of this paper is to elucidate which functional strategy, possibly linked with thallus anatomy, is used by H. lugubris that enables it to be a successful species in the maritime Antarctic. To achieve this goal, we constructed a picture of the lichen’s physiological, anatomical and morphological characteristics by using a broad range of technologies, such as chlorophyll fluorescence, CO exchange and electron microscopy. We found that H. lugubris has a very low net photosynthesis, apparently restricted to the grey areas, but high respiratory rates. Therefore, positive net photosynthesis is only possible at low temperatures. Chlorophyll content is also low but is present in both gray and black areas. Our conclusion is that the only possibility for this species to achieve a positive carbon balance is to be active for long periods under optimal conditions, that means, wet, cold and with enough light, a common combination in this region of Antarctica. Given these constrains, we suggest that H. lugubris is likely to be especially sensitive species to predicted climate warming in the maritime Antarctic.Field work as well as most of the lab experiments were supported by the grant CTM2015-64728-C2-1-R (MINECO/FEDER, UE). Electron microscopy work wassupported by the grant CTM2015-64728-C2-2-R (MINECO/FEDER, UE)

Cost-effectiveness of dexamethasone compared with aflibercept in naïve diabetic macular edema

Abstract Background To assess the cost-effectiveness of the delayed-release device of dexamethasone compared with aflibercept in the treatment of patients with naïve diabetic macular edema (DME) from a societal perspective in the healthcare sector Zaragoza III in Spain. Methods A Markov model with five states defined by visual acuity (VA) in the better-seeing eye (Snellen scale) and an additional death state were constructed. Two cohorts of patients were distributed along the VA states and treated during a year with either dexamethasone or aflibercept. One-year follow-up on each group was performed. Medical costs related to the DME treatment and follow-up, medical costs related to the DME comorbidities, and non-medical-related costs were taken into account. Costs (2020 €), health outcomes (Quality-Adjusted Life Years-QALYs), both discounted at a 3.5% annual rate, and incremental cost-effectiveness ratios (ICER: €/QALY) were determined for a lifetime horizon in the base case analysis. Results Patients treated with dexamethasone were €77,349 more costly and provided 2.667 additional QALYs (€29,002/QALY) than those treated with aflibercept. The variable efficiency per patient was calculated dividing the improvement in quality of life (on the VFQ-25 scale) by the cost of the treatment. With the obtained results it can be concluded that the efficiency of treating the patients with dexamethasone is significantly superior than the efficiency of treating them with aflibercept. Conclusions The cost per QALY gained with the delayed-release device of dexamethasone compared with the one obtained by aflibercept in the naïve DME population is just below the €30,000 threshold, below which, new drugs are sometimes regarded as cost-effective strategies in Spain. In this model, the key variables with greater impact on the cost-effectiveness results were the selected time horizon, the chosen extrapolation method and the number of aflibercept and dexamethasone injections

Subclinical myocardial dysfunction is revealed by speckle tracking echocardiography in patients with Cornelia de Lange syndrome

Echocardiography; Lange syndrome; Myocardial dysfunctionEcocardiografia; Síndrome de Lange; Disfunció miocàrdicaEcocardiografía; Síndrome de Lange; Disfunción miocárdicaThis study assesses a possible cardiac dysfunction in individuals with Cornelia de Lange syndrome (CdLS) without diagnosed congenital heart disease (CHD) and its association with other factors. Twenty patients and 20 controls were included in the study divided into three age-dependent groups (A:  20 yrs), and were evaluated using conventional echocardiography, tissue doppler imaging (TDI), two-dimensional speckle tracking and genetic and biochemical analyses. The left ventricular global longitudinal strain (GLS) was altered (< 15.9%) in 55% of patients, being pathological in the older group (A: 19.7 ± 6.6; B: -17.2 ± 4.7; C: -13.6 ± 2.9). The speckle tracking technique revealed a downward trend in the values of strain, strain rate and velocity, especially in the oldest group. Likewise, the ejection fraction (LVEF) and shortening fraction (LVFS) values, although preserved, also showed a decreased with age (p < 0.05). The analytical markers of cardiovascular risk and cardiac function showed no alterations. The molecular analyses revealed 16 individuals carrying pathogenic variants in NIPBL, two with variants in SMC1A, one with a variant in RAD21 and one with a HDAC8 variant. This is the first systematic approach that demonstrates that individuals with CdLS may present early cardiomyopathy, which can be detected by speckle tracking technique even before the appearance of clinical symptoms and the alteration of other echocardiographic or analytical parameters. For all these reasons, cardiological followup is suggested even in the absence of CHD, especially from adolescence onwards.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature

Long-Term Follow-Up of Macular Perfusion Evaluated by Optical Coherence Tomography Angiography after Rhegmatogenous Retinal Detachment Surgery

Background: The goal of this study was to investigate macular microvascular changes using optical coherence tomography angiography (OCTA) at one year after successful rhegmatogenous retinal detachment (RRD) surgery. Methods: We performed a cross-section study including RRD treated by pars plana vitrectomy (PPV) with or without scleral buckling and SF6 tamponade. After 12 months, DRI-Triton SS-OCTA was performed. Superficial and deep retinal capillary plexuses (SCP and DCP), choriocapillaris (CC) vessel density (VD), and foveal avascular zone (FAZ) morphology were analyzed. Results were compared with the unaffected contralateral eye. Results: Sixty eyes were included. We observed an increase in VD in the central area of both the SCP and DCP in macula-off eyes treated with PPV + SB and in the SCP of macula-off eyes treated with PPV. Macula-off eyes had a diminished VD for both plexuses in the superior quadrant and in the SCP inferior quadrant in those treated with PPV + SB. The CC flow was diminished in the temporal quadrant of macular-off eyes treated with PPV + SB. Healthy eyes presented higher diameter values than macula-off eyes treated with PPV + SB. FAZ horizontal and vertical diameters were smaller in patients with macula-off RRD vs. macula-on RRD and control groups. Conclusion: Macular vascularity remains almost unchanged one year after successful RRD surgery, irrespective of the surgical technique or prior macular status