Acute seizures in acute ischemic stroke: does thrombolysis have a role to play?

Seizures appear at stroke presentation, during the acute phase or as a late complication of stroke. Thrombolysis has not been investigated as a risk factor despite its potential neurotoxic effect. We try to identify risk factors for seizures during the acute phase of ischemic stroke in a cohort including thrombolysed patients. We undertook a case-control study at a single stroke center using data from Acute Stroke Registry and Analyse of Lausanne (ASTRAL). Patients with seizure occurring during the first 7days following stroke were retrospectively identified. Bi-variable and multivariable statistical analyses were applied to compare cases and randomly selected controls. We identified 28 patients experiencing from seizures in 2,327 acute ischemic strokes (1.2%). All seizures occurred during the first 72h. Cortical involvement, thrombolysis with rt-PA, arterial recanalization, and higher initial NIHSS were statistically associated with seizures in univariated analysis. Backward linear regression identified cortical involvement (OR 7.53, 95% CI 1.6-35.2, p<0.01) and thrombolysis (OR 4.6, 95% CI 1.6-13.4, p=0.01) as being independently associated with seizure occurrence. Overall, 3-month outcome measured by the modified Rankin scale (mRS) was comparable in both groups. In the subgroup of thrombolysed patients, outcome was significantly worse at 3months in the seizure group with 9/12 (75%) patients with mRS ≥3, compared to 6/18 (33.3%) in the seizure-free group (p=0.03). Acute seizures in acute ischemic stroke were relatively infrequent. Cortical involvement and thrombolysis with rt-PA are the principal risk factors. Seizures have a potential negative influence on clinical outcome in thrombolysed patient

Treatment deviating from guidelines does not influence status epilepticus prognosis

Status epilepticus (SE) prognosis is related to nonmodifiable factors (age, etiology), but the exact role of drug treatment is unclear. This study was undertaken to address the prognostic role of treatment adherence to guidelines (TAG). We prospectively studied over 26months a cohort of adults with incident SE (excluding postanoxic). TAG was assessed in terms of drug doses (±30% of recommendations) and medication sequence; its prognostic impact on mortality and return to baseline conditions was adjusted for etiology, SE severity [Status Epilepticus Severity Score (STESS)], and comorbidities. Of 225 patients, 26 (12%) died and 82 (36%) were discharged with a new handicap; TAG was observed in 142 (63%). On univariate analysis, age, etiology, SE severity, and comorbidities were significantly related to outcome, while TAG was associated with neither outcome nor likelihood of SE control. Logistic regression for mortality identified etiology [odds ratio (OR) 18.8, 95% confidence interval (CI) 4.3-82.8] and SE severity (STESS ≥3; OR 1.7, 95% CI 1.2-2.4) as independent predictors, and for lack of return to baseline, again etiology (OR 7.4, 95% CI 3.9-14.0) and STESS ≥3 (OR 1.7, 95% CI 1.4-2.2). Similar results were found for the subgroup of 116 patients with generalized-convulsive SE. Receiver operator characteristic (ROC) analyses confirmed that TAG did not improve outcome prediction. This study of a large SE cohort suggests that treatment adherence to recommendations using current medications seems to play a negligible prognostic role (classIII), confirming the importance of the biological background. Awaiting further treatment trials, it appears mandatory to apply resources towards identification of new therapeutic approache

Growth Route Toward III-V Multispectral Solar Cells on Silicon

To date, high efficiency multijunction solar cells have been developed on Ge or GaAs substrates for space applications, and terrestrial applications are hampered by high fabrication costs. In order to reduce this cost, we propose a breakthrough technique of III-V compound heteroepitaxy on Si substrates without generation of defects critical to PV applications. With this technique we expect to achieve perfect integration of heterogeneous Ga1-xInxAs micro-crystals on Si substrates. In this paper, we show that this is the case for x=0. GaAs crystals were grown by Epitaxial Lateral Overgrowth on Si (100) wafers covered with a thin SiO2 nanostructured layer. The cristallographic structure of these crystals is analysed by MEB and TEM imaging. Micro-Raman and Micro-Photomuminescence spectra of GaAs crystals grown with different conditions are compared with those of a reference GaAs wafer in order to have more insight on eventual local strains and their cristallinity. This work aims at developping building blocks to further develop a GaAs/Si tandem demonstrator with a potential conversion efficiency of 29.6% under AM1.5G spectrum without concentration, as inferred from our realistic modeling. This paper shows that Epitaxial Lateral Overgrowth has a very interesting potential to develop multijunction solar cells on silicon approaching the today 30.3% world record of a GaInP/GaAs tandem cell under the same illumination conditions, but on a costlier substrate than silicon.Comment: Preprint of the 28th EUPVSEC proceedings, September 2013, Paris, France. (5 pages

Evaluation of fouling resistances during the ultrafiltration of whey model solutions

[EN] In the last decades, the ultrafiltration of whey has grown in importance as a "green" technique. However, since fouling is an important drawback, researchers focused on its prediction by mathematical models. In this work, three ultrafiltration membranes of different molecular weight cut-offs and materials were used to ultrafilter whey model solutions of different protein concentrations. As a novelty, a resistance-in-series model that accounts for the time evolution of the fouling resistances was considered. The results demonstrated that the higher the protein and salt concentrations in the feed solutions were, the greater the fouling degree was. The resistance-in-series model was accurately fitted to the experimental data for each membrane and feed solution used. The results showed that the resistance due to adsorption dominated the first minutes of operation, while the membrane characteristics (surface roughness and hydrophilicity/hydrophobicity) played an important role in the growth of the cake layer. (C) 2017 Elsevier Ltd. All rights reserved.The authors of this work wish to gratefully acknowledge the financial support provided by the Spanish Ministry of Science and Innovation through its project CTM2010-20186.Corbatón Báguena, MJ.; Alvarez Blanco, S.; Vincent Vela, MC. (2018). Evaluation of fouling resistances during the ultrafiltration of whey model solutions. Journal of Cleaner Production. 172:358-367. https://doi.org/10.1016/j.jclepro.2017.10.149S35836717

Annealing post-drawn polycaprolactone (PCL) nanofibers optimizes crystallinity and molecular alignment and enhances mechanical properties and drug release profiles

Post-drawn PCL nanofibers can be molecularly tuned to have a variety of mechanical properties and drug release profiles depending on the temperature and time of annealing, which has implications for regenerative medicine and drug delivery applications. Post-drawing polycaprolactone (PCL) nanofibers has previously been demonstrated to drastically increase their mechanical properties. Here the effects of annealing on post-drawn PCL nanofibers are characterized. It is shown that room temperature storage and in vivo temperatures increase crystallinity significantly on the order of weeks, and that high temperature annealing near melt significantly increases crystallinity and molecular orientation on the order of minutes. The kinetics of crystallization were assessed using an anneal and quench approach. High temperature annealing also increased the ultimate tensile strength and toughness of the fibers and changed the release profile of a model drug absorbed in PCL nanofibers from first-order to zero-order kinetics

EEG recording latency in critically ill patients: Impact on outcome. An analysis of a randomized controlled trial (CERTA).

OBJECTIVE To assess, in adults with acute consciousness impairment, the impact of latency between hospital admission and EEG recording start, and their outcome. METHODS We reviewed data of the CERTA trial (NCT03129438) and explored correlations between EEG recording latency and mortality, Cerebral Performance Categories (CPC), and modified Rankin Scale (mRS) at 6 months, considering other variables, using uni- and multivariable analyses. RESULTS In univariable analysis of 364 adults, median latency between admission and EEG recordings was comparable between surviving (61.1 h; IQR: 24.3-137.7) and deceased patients (57.5 h; IQR: 22.3-141.1); p = 0.727. This did not change after adjusting for potential confounders, such as lower Glasgow Coma Score on enrolment (p < 0.001) and seizure or status epilepticus detection (p < 0.001). There was neither any correlation between EEG latency and mRS (rho 0.087, p 0.236), nor with CPC (rho = 0.027, p = 0.603). CONCLUSION This analysis shows no correlation between delays of EEG recordings and mortality or functional outcomes at 6 months in critically ill adults. SIGNIFICANCE These findings might suggest that in critically ill adults mortality correlates with underlying brain injury rather than EEG delay

Cambios ambientales del último milenio en sedimentos lacustres del Lago Thompson, Patagonia Chilena Norte

Este estudio se enfoca en un análisis multiproxy de un testigo sedimentario del Lago Thompson (area 1 km2; 751 masl ; 45°38’S 72°47’W) obtenido en 2008 (LT08-E, 130 cm), con el objetivo de documentar la variabilidad climática durante el último milenio en la Patagonia Chilena Norte y su impacto sobre el ambiente. El modelo de datación se basó en cinco fechados de 14C. Los resultados de 210Pb y 137 Cs no permitieron estimar la tasa de sedimentación para la parte superficial del núcleo. El lago Thompson esta caracterizado por una pequeña cuenca de suaves pendientes y sus sedimentos están dominados por limo arcilloso y partículas amorfas (principalmente diatomeas). Esto último es sustentado por la relación atómica de carbono/nitrógeno (C/N) que indica el origen fitoplanctónico del sedimento (8-10). Los perfiles de rayos –X, susceptibilidad magnética y LOI 550ºC evidencian dos depósitos volcánicos en 1410-1440 y 1780-1790 AD. Los perfiles de C/N y sílice biogénica (SiB) sugieren una alta productividad durante un periodo equivalente a la Pequeña Edad del Hielo (1650-1850 AD), con una máxima intensidad durante ~1800 AD. Desde 1850 AD hasta la actualidad, los perfiles de LOI 550ºC y SiB evidencian una reciente eutrofización y aumento del nivel del lago (asociado con aumento de temperaturas y humedad). Además, los perfiles de SiB presentan una correlación inversa con las temperaturas reconstruidas por anillos de árboles en la Patagonia. El contenido de diatomeas es dominado por especies planctónicas (Aulacoseira sp. y Cyclotella sp.), mientras que taxa bentónicos no muestran una buena diversificación en comparación a otros lagos de la Patagonia. La abundancia de diatomeas muestra respuestas específicas a los depósitos volcánicos con una disminución de Aulacoseira sp.. La relación planctónica/bentónica permite identificar dos periodos de alto y bajo nivel del lago coincidiendo con fases húmedas y secas de la Pequeña Edad de Hielo (1200-1650 y 1650-1850 AD). La realización de análisis sedimentológicos, geoquímicos y de microfósiles permitiría una mejor caracterización de los modelos de depositación del sedimento (impregnación del núcleo sedimentario) y de la interacción entre depósitos volcánicos y diatomeas. Agradecimientos a Fondecyt Nº1070508, FNRS 1360 2007-2010 y ULg CFRA 1060 2009-2010

Exploring the extraction of the bioactive content from the two-phase olive mill waste and further purification by ultrafiltration

[EN] The two-phase olive mill waste is enormously produced in the Mediterranean area. This major waste is significantly rich in bioactive compounds that are highly valued by industry, such as phenolic and triterpenic compounds. Here, a thorough study of the most suitable solvent, extraction time and temperature for the largevolume, solid-liquid extraction of bioactive compounds has been made, in order to achieve maximum concentrations of the target compounds. Ultrasound effect has been considered. A deep characterization of the extracts by high-performance liquid chromatography coupled with electrospray-quadrupole-time of flight-mass spectrometry (LC-ESI-qToF-MS) has contributed to evaluate the effect of the operational parameters on the extraction performance. Forty-four compounds have been found and classified in their corresponding chemical families. At the optimum experimental conditions (EtOH 50% (v/v), 40 degrees C, ultrasound-assisted), more than 6.8 mg/g of bioactive content was recovered, and it was later purified by means of ultrafiltration. The membrane UP005 retained a significant percentage of the organic matter, whereas most of the bioactive compounds were recovered in the permeate. This contributed not only to revalorize this waste, but also to reduce its organic load and phytotoxicity, thus protecting the ecosystem of the final disposal zone of the residue.Funding Grant CTM2017-88645-R, funded by MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe. Additionally, the grant PRE2018-08524 was funded by MCIN/AEI/10.13039/501100011033 and by ESF Investing in your future. Funding for open access charge: CRUE-Universitat Politècnica de València.Sánchez-Arévalo, CM.; Iborra Clar, A.; Vincent Vela, MC.; Alvarez Blanco, S. (2022). Exploring the extraction of the bioactive content from the two-phase olive mill waste and further purification by ultrafiltration. LWT - Food Science and Technology. 165:1-12. https://doi.org/10.1016/j.lwt.2022.11374211216