Catechol-derivatized poly(vinyl alcohol) as a coating molecule for magnetic nanoclusters

Surface functionalization of superparamagnetic iron oxide nanoparticles (SPIONs) remains indispensable in promoting colloidal stability and biocompatibility. We propose a well-defined and characterized synthesis of a new catechol-functionalized RAFT (reversible addition–fragmentation chain transfer) poly(vinyl alcohol) polymer, which can be anchored onto hydrophobic SPIONs via a one-pot emulsion ligand exchange process. Both single and clustered nanoparticles are obtained and can be separated from each other. As clustered SPIONs are receiving increasing attention, this new macroligand might be of considerable interest for both basic and applied sciences

Supplementary Notes - Defect engineering of silicon with ion pulses from laser acceleration

14 pages. -- Supplementary Note 1. Time lapse movie showing evaporation of the aluminum foil mask during 100 shots. -- Supplementary Note 2. Photoluminescence (PL) and Secondary Ion Mass Spectrometry (SIMS) data correlation to PL data. -- Supplementary Note 3. Details on energy deposition and heat calculations. -- Supplementary Note 4. Details on Nuclear Reaction Analysis (NRA). -- Supplementary Note 5. Details on channeling Rutherford Backscattering (ch-RBS). -- Supplementary Note 6. Supplemental material on Density Functional Theory (DFT) calculations of G and W-centers in silicon.Peer reviewe

Defect engineering of silicon with ion pulses from laser acceleration

Defect engineering is foundational to classical electronic device development and for emerging quantum devices. Here, we report on defect engineering of silicon with ion pulses from a laser accelerator in the laser intensity range of 1019 W cm−2 and ion flux levels of up to 1022 ions cm−2 s−1, about five orders of magnitude higher than conventional ion implanters. Low energy ions from plasma expansion of the laser-foil target are implanted near the surface and then diffuse into silicon samples locally pre-heated by high energy ions from the same laser-ion pulse. Silicon crystals exfoliate in the areas of highest energy deposition. Color centers, predominantly W and G-centers, form directly in response to ion pulses without a subsequent annealing step. We find that the linewidth of G-centers increases with high ion flux faster than the linewidth of W-centers, consistent with density functional theory calculations of their electronic structure. Intense ion pulses from a laser-accelerator drive materials far from equilibrium and enable direct local defect engineering and high flux doping of semiconductors.This work was supported by the Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy, under Contract No. DE-AC02-05CH11231. Experiments at the BELLA Center were enabled through facilities developed by HEP and LaserNetUS. TS and JGL gratefully acknowledge support by the coordinated research project “F11020” of the International Atomic Energy Agency (IAEA). LZT and JS were supported by the Molecular Foundry, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231Peer reviewe

Defect engineering of silicon with ion pulses from laser acceleration

Defect engineering and doping of semiconductors by ion irradiation are essential in large-scale integration of electronic devices. Here, intense ion pulses from a laser-accelerator, with flux levels up to 1022 ions cm-2 s-1, are used to induce and optimize silicon color centers and photon emitters in the telecom band

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey

International audienceBackground Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France. Methods In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC). Results All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications. Conclusion This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field

Impact of COVID‐19 on thrombus composition and response to thrombolysis: Insights from a monocentric cohort population of COVID‐19 patients with acute ischemic stroke

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Intravenous thrombolysis and thrombectomy decisions in acute ischemic stroke: An interrater and intrarater agreement study

International audiencePurpose. - We aimed to assess agreement on intravenous tissue-plasminogen activator (IV tPA) and mechanical thrombectomy (MT) management decisions in acute ischemic stroke (AIS) patients. Secondary objectives were to assess agreement on Diffusion-Weighted-Imaging-Alberta-Stroke-Program-EArly-CT-Score (DWI-ASPECTS), and clinicians' willingness to recruit patients in a randomized controlled trial (RCT) comparing medical management with or without MT. Materials and Methods. - Studies assessing agreement of IV tPA and MT were systematically reviewed. An electronic portfolio of 41 AIS patients was sent to randomly selected providers at French stroke centers. Raters were asked 4 questions for each case: (1) What is the DWI-ASPECTS? (2) Would you perform IV tPA? (3) Would you perform MT? (4) Would you include the patient in a RCT comparing standard medical therapy with or without MT? Twenty responders were randomly selected to study intrarater agreement. Agreement was assessed using Fleiss' Kappa statistics. Results. - The review yielded two single center studies involving 2-5 raters, with various results. The electronic survey was answered by 86 physicians (60 vascular neurologists and 26 interventional neuroradiologists). The interrater agreement was moderate for IV tPA treatment decisions (kappa = 0.565 [0.420-0.680]), but only fair for MT (kappa = 0.383 [0.289-0.491]) and for combined treatment decisions (kappa = 0.399 [0.320-0.486]). The intrarater agreement was at least substantial for the majority of raters. The interrater agreement for DWI-ASPECTS was fair (kappa = 0.325 [0.276-0.387]). Physicians were willing to include a mean of 14 +/- 9 patients (33.1% +/- 21.7%) in a RCT. Conclusion. - Disagreements regarding the use of IVtPA or MT in the management of AIS patients remain frequent. Further trials are needed to resolve the numerous areas of uncertainty. (C) 2019 Elsevier Masson SAS. All rights reserved

Thrombectomy complications in large vessel occlusions: Incidence, predictors, and clinical impact in the ETIS registry

International audienceBACKGROUND AND PURPOSE: Procedural complications in thrombectomy for large vessel occlusions of the anterior circulation are not well described. We investigated the incidence, risk factors, and clinical implications of thrombectomy complications in daily clinical practice. METHODS: We used data from the ongoing prospective multicenter observational Endovascular Treatment in Ischemic Stroke Registry in France. The present study is a retrospective analysis of 4029 stroke patients with anterior large vessel occlusions treated with thrombectomy between January 2015 and May 2020 in 18 centers. We systematically collected procedural data, incidence of embolic complications, perforations and dissections, clinical outcome at 90 days, and hemorrhagic complications. RESULTS: Procedural complications occurred in 7.99% (95% CI, 7.17%–8.87%), and embolus to a new territory (ENT) was the most frequent (5.2%). Predictors of ENTs were terminal carotid/tandem occlusion (odds ratio [OR], 5 [95% CI, 2.03–12.31]; P<0.001) and an increased total number of passes (OR, 1.22 [95% CI, 1.05–1.41]; P=0.006). ENTs were associated to worse clinical outcomes (90-day modified Rankin Scale score, 0–2; adjusted OR, 0.4 [95% CI, 0.25–0.63]; P<0.001), increased mortality (adjusted OR, 1.74 [95% CI, 1.2–2.53]; P<0.001), and symptomatic intracerebral hemorrhage (adjusted OR, 1.87 [95% CI, 1.15–3.03]; P=0.011). Perforations occurred in 1.69% (95% CI, 1.31%–2.13%). Predictors of perforations were terminal carotid/tandem occlusions (39.7% versus 27.6%; P=0.028). 40.7% of patients died at 90 days, and the overall rate of poor outcome was 74.6% in case of perforation. Dissections occurred in 1.46% (95% CI, 1.11%–1.88%) and were more common in younger patients (median age, 64.2 versus 70.2 years; P=0.002). Dissections did not affect the clinical outcome at 90 days. Besides dissection, complications were independent of the thrombectomy technique. CONCLUSIONS: Thrombectomy complication rate is not negligible, and ENTs were the most frequent. ENTs and perforations were associated with disability and mortality, and terminal carotid/tandem occlusions were a risk factor

Successful thrombectomy is beneficial in patients with pre-stroke disability: Results from an international multicenter cohort study

International audienceAbstract Excessive alcohol consumption is the leading cause of liver diseases in Western countries, especially in France. Alcohol‐related liver disease (ARLD) is an extremely broad context and there remains much to accomplish in terms of identifying patients, improving prognosis and treatment, and standardising practices. The French Association for the Study of the Liver wished to organise guidelines together with the French Alcohol Society in order to summarise the best evidence available about several key clinical points in ARLD. These guidelines have been elaborated based on the level of evidence available in the literature and each recommendation has been analysed, discussed and voted by the panel of experts. They describe how patients with ARLD should be managed nowadays and discuss the main unsettled issues in the field