Self-processing in coma, unresponsive wakefulness syndrome and minimally conscious state

IntroductionBehavioral and cerebral dissociation has been now clearly established in some patients with acquired disorders of consciousness (DoC). Altogether, these studies mainly focused on the preservation of high-level cognitive markers in prolonged DoC, but did not specifically investigate lower but key-cognitive functions to consciousness emergence, such as the ability to take a first-person perspective, notably at the acute stage of coma. We made the hypothesis that the preservation of self-recognition (i) is independent of the behavioral impairment of consciousness, and (ii) can reflect the ability to recover consciousness.MethodsHence, using bedside Electroencephalography (EEG) recordings, we acquired, in a large cohort of 129 severely brain damaged patients, the brain response to the passive listening of the subject’s own name (SON) and unfamiliar other first names (OFN). One hundred and twelve of them (mean age ± SD = 46 ± 18.3 years, sex ratio M/F: 71/41) could be analyzed for the detection of an individual and significant discriminative P3 event-related brain response to the SON as compared to OFN (‘SON effect’, primary endpoint assessed by temporal clustering permutation tests).ResultsPatients were either coma (n = 38), unresponsive wakefulness syndrome (UWS, n = 30) or minimally conscious state (MCS, n = 44), according to the revised version of the Coma Recovery Scale (CRS-R). Overall, 33 DoC patients (29%) evoked a ‘SON effect’. This electrophysiological index was similar between coma (29%), MCS (23%) and UWS (34%) patients (p = 0.61). MCS patients at the time of enrolment were more likely to emerged from MCS (EMCS) at 6 months than coma and UWS patients (p = 0.013 for comparison between groups). Among the 72 survivors’ patients with event-related responses recorded within 3 months after brain injury, 75% of the 16 patients with a SON effect were EMCS at 6 months, while 59% of the 56 patients without a SON effect evolved to this favorable behavioral outcome.DiscussionAbout 30% of severely brain-damaged patients suffering from DoC are capable to process salient self-referential auditory stimuli, even in case of absence of behavioral detection of self-conscious processing. We suggest that self-recognition covert brain ability could be an index of consciousness recovery, and thus could help to predict good outcome

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome associated with COVID-19: An Emulated Target Trial Analysis.

RATIONALE: Whether COVID patients may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. OBJECTIVES: To estimate the effect of ECMO on 90-Day mortality vs IMV only Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO vs. no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 <80 or PaCO2 ≥60 mmHg). We controlled for confounding using a multivariable Cox model based on predefined variables. MAIN RESULTS: 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability at Day-7 from the onset of eligibility criteria (87% vs 83%, risk difference: 4%, 95% CI 0;9%) which decreased during follow-up (survival at Day-90: 63% vs 65%, risk difference: -2%, 95% CI -10;5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand, and when initiated within the first 4 days of MV and in profoundly hypoxemic patients. CONCLUSIONS: In an emulated trial based on a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and in regions with ECMO capacities specifically organized to handle high demand. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/)

A one year survey of seagrass primary productivity using the diving-PAM technique

Marine magnoliophytes are major primary producers in coastal benthic habitats worldwide. They play a crucial role in the global carbon cycle (one of the more efficient blue carbon wells). Hence, it is necessary to characterise the eco-systemic services seagrass meadows provide. Posidonia oceanica (L.) Delile, the main Mediterranean seagrass species, has high foliar and belowground biomass production. Several methods have been used so far to measure its primary production (e.g., using incubation bells, optodes, biomass and elementary content measurements). A less used method relies on chlorophyll fluorescence measurements through the Pulse Amplitude Modulated (PAM) fluorometry method (Diving - PAM). In the framework of the STARECAPMED project, this study aimed to determine weekly to bimonthly over a one-year period the photosynthetic responses (Yield, relative Electron Transfer Rate, Rapid Light Curve) of P. oceanica. The survey was performed at 10m depth in a pristine meadow (Calvi, Corsica, France). To obtain reliable and comparable data, the protocol was standardized: measurements were performed on the convex middle part of the third leaf, at zenith, during shiny and calm weather days. Results showed that the plant displayed a well-marked seasonality. The mean ETR (μmol e- m-2 s-1 ) of the plant ranged from 2.17 in winter to 21.9 in summer and was linearly correlated throughout the year with the in situ irradiance (PAR irradiance taken perpendicularly to the surface, in the average leaf orientation). The ETR plateaus of the RLCs, ranging from 10.9 to 35.0, and their corresponding maximum PAR intensities evolved similarly. These results demonstrated both the adaptation and the seasonal plasticity of the meadow’s photosynthetic system. Overall the non-destructive PAM technique is a powerful and cost-effective tool to assess the primary productivity of seagrass meadows where other techniques (e.g. optodes) cannot be used and when direct sampling (e.g. biomass measurements) is not allowed

Lost in transition – Learning analytics on the transfer from knowledge acquisition to knowledge application in complex problem solving

Since Complex Problem Solving (CPS) skills represent a key competence for educational success, they are of great relevance for learning analytics. More specifically, CPS serves as a pertinent showcase for addressing a crucial existing gap contemporary education is facing, the gap between students' ability to acquire and subsequently apply knowledge in uncertain situations, which are increasingly important in the 21st century. While the CPS process incorporates both the acquisition and application of knowledge, many earlier studies have focused on identifying the factors relevant for success in knowledge acquisition. Given the dearth of existing research on factors influencing a successful transition between both CPS phases, we investigated the rates of successful and unsuccessful knowledge transition over the course of nine CPS items in a sample of N = 1151 students in 9th grade. Results showed that many participants were unable to transition their knowledge from the acquisition to the application phase, which was presumably due to an inefficient mental model transfer. Furthermore, the likelihood of students being ‘lost in transition’ was higher in more complex items. Implications are discussed in light of learning analytics, and particularly with regard to the factors to be taken into account by future CPS training programs

Intrinsic Evaluation of neutron/gamma Discrimination in Plastic Scintillators

International audienceThis paper is devoted to characterizing plastic scintillators with neutron/gamma discrimination abilities and understanding experimentally the photophysical processes downstream. This experimental work is divided into two main studies, neutron sources irradiations and optical photoionization of a range of organic scintillators. Commercial liquid and plastic scintillators, respectively BC-501A from Saint-Gobain and EJ-200 from Eljen Technologies, are used as references in terms of respectively extremely high [C. Guerrero, et al., “Analysis of the BC-501A Neutron Detector Signals Using the True Pulse Shape,” Nucl. Instrum. Methods Phys. Res. A, Accel. Spectrom. Detect. Assoc. Equip., vol. 597, no. 23, pp. 212-218, 2008] and very poor neutron/gamma discrimination efficient scintillators. We have developed a plastic scintillator [P. Blanc et al., “Neutron/Gamma Pulse Shape Discrimination in Plastic Scintillators: Preparation and Characterization of Various Compositions,”Nucl. Instrum. Methods A, vol. 750, pp. 1-11, Jun. 2014] that shows good discrimination efficiency when compared to plastics that discriminate from literature. We have demonstrated that by exciting with a 70 femtoseconds pulsed laser with energies up to 50 µJ at 260 nm, it was possible to simulate nuclear interactions with matter. As a result of the photoionization, we observed a time-delayed light emission when a sufficient energy deposition was optically achieved on a discriminating plastic and none when the plastic showed no discrimination properties. This work is ongoing at CEA in collaboration with the nuclear measurement industry AREVA/Canberra and the Laboratoire de Chimie Physique from Orsay University

Dispositif Intégré pour l'Analyse par Décharges Électriques et la Miniaturisation de l’Émission photonique

International audienceAu travers de nombreuses collaborations qui perdurent avec le temps, l’ICP et le LPGP proposent dans ce projet émergent de combiner décharges plasma, microfluidique et analyse par spectrométrie de masse. Un dispositif microfluidique sera conçu avec une première partie constituée d’un diluteur de gaz rares. Dans un second module ces gaz seront vecteurisés pour être distribués dans une matrice de microcanaux contenant des solénoïdes. Ces derniers seront alimentés par du courant alternatif nécessaire à la création de microplasmas. Les émissions produites par ces plasmas seront étudiées comme sources de lumière et caractérisées optiquement avant d’envisager pour la suite de ce projet l’intégration de cavités générant de la lumière cohérente et monochromatique. Le deuxième volet de ce projet consistera à réaliser des études de réactivité dans ces microplasmas en y introduisant des molécules (formaldéhyde, ammoniac, eau) pouvant servir de précurseurs conduisant aux molécules plus complexes qui sont à l’origine des briques de la vie (acides aminés). L’analyse des étapes de cette réactivité sera réalisée en couplant la puce microfluidique à des spectromètres de masse FTICR (Fourier Transform Ion Cyclotron Resonance) compacts. Cet ensemble permettra des analyses de COV (composés organiques volatils) en temps réel. Ce projet PALM constituera le socle nécessaire à la demande de financement d’un projet de type ANR ou ERC d’ici trois ans. En effet, on sait que les plasmas sont capables d’augmenter drastiquement les rendements des réactions et l’activité catalytique, ce sont là d’autres perspectives possibles du projet DIADEME

Quantification of 4-hydroxynonenal-protein (HNE-P) and 4-hydroxyhexenal-protein (HHE-P) thio-ether adducts by GC-MS/MS in pork and beef processed meat

International audienc

SEED: AN OPERATIONAL NUMERICAL TOOL FOR DOSIMETRIC RECONSTRUCTION IN CASE OF RADIOLOGICAL OVEREXPOSURE

International audienceIn the event of a radiological accident involving one or more victims and potential high doses, it is essential to know the dose distribution within the body, in order to sort the victims according to the severity of the irradiation, and then to take them to the most suitable medical structures. However, there are currently very a few techniques that can be rapidly deployed on field and capable of characterizing an irradiation.Therefore, a numerical simulation tool has been designed. Called SEED, this tool is integrated into a militarized and hardened device, which can dispense with any communication with a cluster of processors thanks to a powerful multi-core calculator. The user can navigate in three dimensions in the accident scene thanks to a graphical user interface including a “first person” camera. It allows a rapid modeling of this scene, and a visual exchange with the victims and witnesses of the event.In order to ensure the performance of the SEED tool, two dosimetric validations were performed. The first consisted in comparing the dose value provided by SEED to that given by a reference calculation code: MCNPX. The purpose of the second validation was to perform an experiment irradiating a physical dummy equipped with dosemeters and to reconstruct this irradiation using SEED. These two validation protocols have shown very satisfactory results. They confirm that this new tool is able to provide useful information to medical teams in charge of dosimetric triage in case of a major external exposure event

Data_Sheet_1_Self-processing in coma, unresponsive wakefulness syndrome and minimally conscious state.docx

IntroductionBehavioral and cerebral dissociation has been now clearly established in some patients with acquired disorders of consciousness (DoC). Altogether, these studies mainly focused on the preservation of high-level cognitive markers in prolonged DoC, but did not specifically investigate lower but key-cognitive functions to consciousness emergence, such as the ability to take a first-person perspective, notably at the acute stage of coma. We made the hypothesis that the preservation of self-recognition (i) is independent of the behavioral impairment of consciousness, and (ii) can reflect the ability to recover consciousness.MethodsHence, using bedside Electroencephalography (EEG) recordings, we acquired, in a large cohort of 129 severely brain damaged patients, the brain response to the passive listening of the subject’s own name (SON) and unfamiliar other first names (OFN). One hundred and twelve of them (mean age ± SD = 46 ± 18.3 years, sex ratio M/F: 71/41) could be analyzed for the detection of an individual and significant discriminative P3 event-related brain response to the SON as compared to OFN (‘SON effect’, primary endpoint assessed by temporal clustering permutation tests).ResultsPatients were either coma (n = 38), unresponsive wakefulness syndrome (UWS, n = 30) or minimally conscious state (MCS, n = 44), according to the revised version of the Coma Recovery Scale (CRS-R). Overall, 33 DoC patients (29%) evoked a ‘SON effect’. This electrophysiological index was similar between coma (29%), MCS (23%) and UWS (34%) patients (p = 0.61). MCS patients at the time of enrolment were more likely to emerged from MCS (EMCS) at 6 months than coma and UWS patients (p = 0.013 for comparison between groups). Among the 72 survivors’ patients with event-related responses recorded within 3 months after brain injury, 75% of the 16 patients with a SON effect were EMCS at 6 months, while 59% of the 56 patients without a SON effect evolved to this favorable behavioral outcome.DiscussionAbout 30% of severely brain-damaged patients suffering from DoC are capable to process salient self-referential auditory stimuli, even in case of absence of behavioral detection of self-conscious processing. We suggest that self-recognition covert brain ability could be an index of consciousness recovery, and thus could help to predict good outcome.</p

Does the Residues Chirality Modify the Conformation of a Cyclo-Dipeptide? Vibrational Spectroscopy of Protonated Cyclo-diphenylalanine in the Gas Phase

The structure of a protonated diketopiperazine dipeptide, cyclo-diphenylalanine, is studied by means of infrared multiple photon dissociation spectroscopy combined with quantum chemical calculations. Protonation exclusively occurs on the oxygen site and, in the most stable conformer, results to an intramolecular OH···π interaction, accompanied by a CH···π interaction. Higher-energy conformers with free OH and NH···π interactions are observed as well, due to kinetic trapping. Optimization of the intramolecular interactions involving the aromatic ring dictates the geometry of the benzyl substituents. Changing the chirality of one of the residues has consequences on the CH···π interaction, which is of C_αH···π nature for LD, while LL shows a C_βH···π interaction. Higher-energy conformers also display some differences in the nature of the intramolecular interactions