: Seizure onset zone imaging

International audienceStereo-electroencephalography is used to localize the seizure onset zone and connected neuronal networks in surgical candidates suffering from intractable focal epilepsy. The concept of an epileptogenicity index has been proposed recently to represent the likelihood of various regions being part of the seizure onset zone. It quantifies low-voltage fast activity, the electrophysiological signature of seizure onset usually assessed visually by neurologists. Here, we revisit epileptogenicity in light of neuroimaging tools such as those provided in statistical parametric mapping software. Our goal is to propose a robust approach, allowing easy exploration of patients' brains in time and space. The procedure is based upon statistical parametric mapping, which is an established framework for comparing multi-dimensional image data that allows one to correct for inherent multiple comparisons. Statistics can also be performed at the group level, between seizures in the same patient or between patients suffering from the same type of epilepsy using normalization of brains to a common anatomic atlas. Results are obtained from three case studies (insular reflex epilepsy, cryptogenic frontal epilepsy and lesional occipital epilepsy) where tailored resection was performed, and from a group of 10 patients suffering from mesial temporal lobe epilepsy. They illustrate the basics of the technique and demonstrate its very good reproducibility and specificity. Most importantly, the proposed approach to the quantification of the seizure onset zone allows one to summarize complex signals in terms of a time-series of statistical parametric maps that can support clinical decisions. Quantitative neuroimaging of stereo-electroencephalographic features of seizures might thus help to provide better pre-surgical assessment of patients undergoing resective surgery

An optimized D-dimer cut-off value to predict pulmonary thromboembolism in COVID-19 patients

Pulmonary thromboembolism (PTE) is a common complication in coronavirus disease 2019 (COVID-19) patients. Elevated D-dimer levels are observed even in the absence of PTE, reducing its discriminative ability as a screening test. It is unknown whether conventional D-dimer cut-off values, as used in the YEARS algorithm, apply to COVID-19 patients. This study aimed to determine the optimal D-dimer cut-off value to predict PTE in COVID-19 patients. All confirmed COVID-19 patients with a computed tomography pulmonary angiography (CTPA) performed ≤5 days after admission due to suspicion of PTE between March 2020 and February 2021, at Medisch Spectrum Twente, The Netherlands, were retrospectively analyzed. The association between PTE and D-dimer levels prior to CTPA, and other potential predictors, was analyzed using logistic regression analyses. The optimal cut-off value was identified using receiver operating characteristic (ROC) curve analyses. In 142 patients, PTE prevalence was 20.4%. The optimal cut-off value was 750 ng/mL (sensitivity 100%; specificity 19.5%; negative predictive value 100%; positive predictive value 24.2%). In total, 15 of 113 (13%) patients without PTE had a D-dimer level ≥500 and &lt;750 ng/mL. In our population of patients hospitalized with COVID-19, a D-dimer level &lt;750 ng/mL safely excluded PTE. Compared to the YEARS 500 ng/mL cut-off value, 13% fewer patients are in need of a CTPA, with similar sensitivity. Future research is required for external validation.</p

IntrAnat Electrodes: A Free Database and Visualization Software for Intracranial Electroencephalographic Data Processed for Case and Group Studies

In some cases of pharmaco-resistant and focal epilepsies, intracranial recordings performed epidurally (electrocorticography, ECoG) and/or in depth (stereoelectroencephalography, SEEG) can be required to locate the seizure onset zone and the eloquent cortex before surgical resection. In SEEG, each electrode contact records brain’s electrical activity in a spherical volume of 3 mm diameter approximately. The spatial coverage is around 1% of the brain and differs between patients because the implantation of electrodes is tailored for each case. Group studies thus need a large number of patients to reach a large spatial sampling, which can be achieved more easily using a multicentric approach such as implemented in our F-TRACT project (f-tract.eu). To facilitate group studies, we developed a software—IntrAnat Electrodes—that allows to perform virtual electrode implantation in patients’ neuroanatomy and to overlay results of epileptic and functional mapping, as well as resection masks from the surgery. IntrAnat Electrodes is based on a patient database providing multiple search criteria to highlight various group features. For each patient, the anatomical processing is based on a series of software publicly available. Imaging modalities (Positron Emission Tomography (PET), anatomical MRI pre-implantation, post-implantation and post-resection, functional MRI, diffusion MRI, Computed Tomography (CT) with electrodes) are coregistered. The 3D T1 pre-implantation MRI gray/white matter is segmented and spatially normalized to obtain a series of cortical parcels using different neuroanatomical atlases. On post-implantation images, the user can position 3D models of electrodes defined by their geometry. Each electrode contact is then labeled according to its position in the anatomical atlases, to the class of tissue (gray or white matter, cerebro-spinal fluid) and to its presence inside or outside the resection mask. Users can add more functionally informed labels on contact, such as clinical responses after electrical stimulation, cortico-cortical evoked potentials, gamma band activity during cognitive tasks or epileptogenicity. IntrAnat Electrodes software thus provides a means to visualize multimodal data. The contact labels allow to search for patients in the database according to multiple criteria representing almost all available data, which is to our knowledge unique in current SEEG software. IntrAnat Electrodes will be available in the forthcoming release of BrainVisa software and tutorials can be found on the F-TRACT webpage

Benefits and harm of systemic steroids for short- and long-term use in rhinitis and rhinosinusitis : an EAACI position paper

Correction: Volume: 10 Issue: 1 Article Number: 38 DOI: 10.1186/s13601-020-00343-w Published: SEP 28 2020Because of the inflammatory mechanisms of most chronic upper airway diseases such as rhinitis and chronic rhinosinusitis, systemic steroids have been used for their treatment for decades. However, it has been very well documented that-potentially severe-side-effects can occur with the accumulation of systemic steroid courses over the years. A consensus document summarizing the benefits of systemic steroids for each upper airway disease type, as well as highlighting the potential harms of this treatment is currently lacking. Therefore, a panel of international experts in the field of Rhinology reviewed the available literature with the aim of providing recommendations for the use of systemic steroids in treating upper airway disease.Peer reviewe

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Dissection de l'aorte : détection de l'artère d'Adamkiewicz en IRM 3 Tesla intégrée au bilan aortique

REIMS-BU Santé (514542104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Cartographies d épileptogénicité évaluées en SEEG : apport des oscillations hautes fréquences (60-100Hz) ictales dans la définition de la zone de début de crise

Les oscillations hautes fréquences (HFO) étudiées en stéréo-électroencéphalographie (SEEG) chez les patients présentant une épilepsie partielle pharmaco-résistante, semblent être le témoin de l épileptogénèse et reflètent assez fidèlement, par leur topographie, la seizure onset zone (SOZ). Récemment, notre équipe a fait état d une nouvelle méthode de cartographie de la SOZ basée sur l augmentation de puissance des HFO60-100 (HFO de fréquence comprise entre 60 et 100 Hz). Cette méthode, qui permet d établir une cartographie des réseaux neuronaux impliqués dans l initiation de la crise, a été appliquée à tous les patients implantés en SEEG entre 2009 et 2011 au CHU de Grenoble, qui avaient présenté au moins une crise épileptique spontanée. 21 patients ont ainsi été étudiés, de SOZ majoritairement néocorticale. La puissance ictale des HFO60-100 a été quantifiée pour chaque crise, puis des cartographies statistiques ont été utilisées pour représenter les régions corticales présentant une activation significative des HFO60-100 au début de la crise, comparativement aux HFO60-100 intercritiques. Pour tous les patients étudiés, une activation critique significative des HFO60-100 a été démontrée, quelle que soit la topographie de la SOZ, indépendamment de la présence d une lésion épileptogène. La topographie des HFO60-100 activées au début des crises semble corrélée à celle de la SOZ. Pour 11 des patients opérés, le pronostic chirurgical s avérait d autant plus favorable que la résection réalisée contenait les régions cérébrales présentant une activation significative des HFO60-100 ictales.High gamma oscillations (HFO, >60 Hz) at seizure onset are strongly associated to epileptogenesis, and their localising value for the seizure onset zone (SOZ) has been underlined using quantitative measures such as the epileptogenicity index. In particular, we recently reported a new method that produces images of epileptogenicity based on the detection of significant increase of HFO at seizure onset in stereotactic coordinates derived from patient s MRI (magnetic resonance imaging). Here, we applied the same analysis to 21 consecutive patients who underwent stereo-electroencephalography (SEEG) recordings between 2009 and 2011, and in whom at least one spontaneous seizure was recorded. Power of HFO ranging from 60 to 100Hz band (ictalHFO60-100) was quantified at onset for each seizure, and statistical parametric maps were used to represent the cortex areas displaying significant ictalHFO60-100 when compared to an interictal baseline. Analysis was performed at the patient level per seizure, with a group analysis for every patient. All patients presented a significant epileptogenicity map at seizure onset, whatever seizure onset location or histological lesion they had. IctalHFO60-100 map was highly reproducible over seizures per patient, and most significant ictalHFO60-100 had the same localisation as epileptogenic lesions. For 11 patients who underwent a 3DT1 MRI in the post-operative period, the removal of cortex areas displaying ictalHFO60-100 was associated to a better outcome. Epileptogenicity map is useful to evaluate the SOZ in the pre-surgical period. This new tool associated to SEEG might help to improve the surgical outcome of medically-intractable epilepsies.GRENOBLE1-BU Médecine pharm. (385162101) / SudocSudocFranceF

Cochaperone Interactions in Export of the Type III Needle Component PscF of Pseudomonas aeruginosa▿

Type III secretion (T3S) systems allow the export and translocation of bacterial effectors into the host cell cytoplasm. Secretion is accomplished by an 80-nm-long needle-like structure composed, in Pseudomonas aeruginosa, of the polymerized form of a 7-kDa protein, PscF. Two proteins, PscG and PscE, stabilize PscF within the bacterial cell before its export and polymerization. In this work we screened the 1,320-Å2 interface between the two chaperones, PscE and PscG, by site-directed mutagenesis and determined hot spot regions that are important for T3S function in vivo and complex formation in vitro. Three amino acids in PscE and five amino acids in PscG, found to be relevant for complex formation, map to the central part of the interacting surface. Stability assays on selected mutants performed both in vitro on purified PscE-PscG complexes and in vivo on P. aeruginosa revealed that PscE is a cochaperone that is essential for the stability of the main chaperone, PscG. Notably, when overexpressed from a bicistronic construct, PscG and PscF compensate for the absence of PscE in cytotoxic P. aeruginosa. These results show that all of the information needed for needle protein stabilization and folding, its presentation to the T3 secreton, and its export is present within the sequence of the PscG chaperone

Kinetics and diffusional limitations in nanostructured heterogeneous catalyst with controlled pore texture

Nanostructured carbon xerogels with controlled pore texture are used as catalyst support for the oxidation in aqueous phase of D-glucose into D-gluconic acid on Pd-Bi/C catalysts. X-ray photoelectron spectroscopy shows that metal active sites are not homogeneously dispersed in the spherical support particle but are concentrated in an external spherical layer. The influence of mass transfers on reaction kinetics is highlighted. Internal diffusional limitations are quantified using the Weisz modulus. It is shown that measuring the true kinetic reaction rate implies to choose the experimental conditions within a small range of values. (C) 2010 Elsevier B.V. All rights reserved