265 research outputs found

    Directive 2010/63/UE : the explicit and the implicit

    Get PDF
    On september 2010, a new European Directive for the protection of vertebrate animals used for experimental purposes was signed. It replaces the previous 1986 Directive and represents a significative change in increasing substantially the protection of experimental animals. The changes concern mainly the domain of application, the structure and the management of the animal facilities either breeding colonies or research laboratories. The whole staff should acquire qualifications more finely tuned to their duties. The authorization of projects based on their ethical value is now under control of an administrative process. These modifications impact on ways of functioning in all the establishments with for objective a better consideration of 3R (Reduction, Refinement Replacement) to the advantage of animals. However, their implementation is not always easy to do ; it is essential to find the good compromises to increase the standards of animal protection while protecting the possibility of pursuing a high quality expĂ©rimental research in EuropeLa Directive europĂ©enne (2010/63/UE) relative à la protection des animaux utilisés à des fins scientifiques, a Ă©tĂ© signĂ©e le 22 septembre 2010 et remplace la directive de 1986. Ce texte modifie largement le prĂ©cĂ©dent et a pour objectif de protĂ©ger davantage les animaux utilisĂ©s en recherche. Les modifications portent sur le champ d’application, les structures et le fonctionnement des Ă©tablissements dans lesquels se trouvent les animaux, les personnels qui devront avoir des compĂ©tences plus ciblĂ©es vers leurs missions et l’évaluation Ă©thique des projets, encadrĂ©e par un processus d’autorisation. Ces modifications impactent les modes de fonctionnement dans tous les Ă©tablissements avec pour objectif une meilleure prise en compte des 3R (Reduction, Refinement Replacement) au bĂ©nĂ©fice des animaux. Toutefois, leur mise en oeuvre n’est pas toujours aisĂ©e; il est essentiel de trouver les bons compromis pour augmenter les standards de protection des animaux tout en prĂ©servant la possibilitĂ© de poursuivre en Europe une recherche expĂ©rimentale de qualit

    Modifications of urodynamic parameters in the scrapie ewes

    Get PDF
    Des explorations urodynamiques ont Ă©tĂ© effectuĂ©es chez 8 brebis nor males et chez 8 brebis atteintes de tremblante. Les brebis malades prĂ©sentent un taux Ă©levĂ© de contractions vĂ©sicales en phase de remplissage (contrac tions non inhibĂ©es du dĂ©trusor) et une instabilitĂ© urĂ©trale. Les autres para mĂštres de l'Ă©tude urodynamique ne sont pas modifiĂ©s de façon significative. Ces troubles du fonctionnement de l’appareil vĂ©sico-sphinctĂ©rien sont comparĂ©s Ă  des troubles observĂ©s chez l’homme au cours de certaines affec tions du systĂšme nerveux central.Ewes (8 normal and 8 with scrapie) were submitted to an urodynamic study. Diseased ewes showed frequently contractions of the bladder known as uninhibited contractions of detrusor. They exhibited also an instability of urethra. The other values of cystomanometric analysis were not signifi cantly affected. Theses modifications of the bladder and urethra are compa red to some diseases observed in people suffering of central nervous system alterations

    Therapeutic efficacy of microtube-embedded chondroitinase ABC in a canine clinical model of spinal cord injury

    Get PDF
    Many hundreds of thousands of people around the world are living with the long-term consequences of spinal cord injury and they need effective new therapies. Laboratory research in experimental animals has identified a large number of potentially translatable interventions but transition to the clinic is not straightforward. Further evidence of efficacy in more clinically-relevant lesions is required to gain sufficient confidence to commence human clinical trials. Of the many therapeutic candidates currently available, intraspinally applied chondroitinase ABC has particularly well documented efficacy in experimental animals. In this study we measured the effects of this intervention in a double-blinded randomized controlled trial in a cohort of dogs with naturally-occurring severe chronic spinal cord injuries that model the condition in humans. First, we collected baseline data on a series of outcomes: forelimb-hindlimb coordination (the prespecified primary outcome measure), skin sensitivity along the back, somatosensory evoked and transcranial magnetic motor evoked potentials and cystometry in 60 dogs with thoracolumbar lesions. Dogs were then randomized 1:1 to receive intraspinal injections of heat-stabilized, lipid microtube-embedded chondroitinase ABC or sham injections consisting of needle puncture of the skin. Outcome data were measured at 1, 3 and 6 months after intervention; skin sensitivity was also measured 24 h after injection (or sham). Forelimb-hindlimb coordination was affected by neither time nor chondroitinase treatment alone but there was a significant interaction between these variables such that coordination between forelimb and hindlimb stepping improved during the 6-month follow-up period in the chondroitinase-treated animals by a mean of 23%, but did not change in controls. Three dogs (10%) in the chondroitinase group also recovered the ability to ambulate without assistance. Sensitivity of the dorsal skin increased at 24 h after intervention in both groups but subsequently decreased to normal levels. Cystometry identified a non-significant improvement of bladder compliance at 1 month in the chondroitinase-injected dogs but this did not persist. There were no overall differences between groups in detection of sensory evoked potentials. Our results strongly support a beneficial effect of intraspinal injection of chondroitinase ABC on spinal cord function in this highly clinically-relevant model of chronic severe spinal cord injury. There was no evidence of long-term adverse effects associated with this intervention. We therefore conclude that this study provides strong evidence in support of initiation of clinical trials of chondroitinase ABC in humans with chronic spinal cord injury

    Tensorpac: An open-source Python toolbox for tensor-based phase-amplitude coupling measurement in electrophysiological brain signals

    Get PDF
    Despite being the focus of a thriving field of research, the biological mechanisms that underlie information integration in the brain are not yet fully understood. A theory that has gained a lot of traction in recent years suggests that multi-scale integration is regulated by a hierarchy of mutually interacting neural oscillations. In particular, there is accumulating evidence that phase-amplitude coupling (PAC), a specific form of cross-frequency interaction, plays a key role in numerous cognitive processes. Current research in the field is not only hampered by the absence of a gold standard for PAC analysis, but also by the computational costs of running exhaustive computations on large and high-dimensional electrophysiological brain signals. In addition, various signal properties and analyses parameters can lead to spurious PAC. Here, we present Tensorpac, an open-source Python toolbox dedicated to PAC analysis of neurophysiological data. The advantages of Tensorpac include (1) higher computational efficiency thanks to software design that combines tensor computations and parallel computing, (2) the implementation of all most widely used PAC methods in one package, (3) the statistical analysis of PAC measures, and (4) extended PAC visualization capabilities. Tensorpac is distributed under a BSD-3-Clause license and can be launched on any operating system (Linux, OSX and Windows). It can be installed directly via pip or downloaded from Github (https://github.com/EtienneCmb/tensorpac). By making Tensorpac available, we aim to enhance the reproducibility and quality of PAC research, and provide open tools that will accelerate future method development in neuroscience

    A feasibility study of a complete low-cost consumer-grade brain-computer interface system

    Get PDF
    Brain-computer interfaces (BCIs) are technologies that provide the user with an alternative way of communication. A BCI measures brain activity (e.g. EEG) and converts it into output commands. Motor imagery (MI), the mental simulation of movements, can be used as a BCI paradigm, where the movement intention of the user can be translated into a real movement, helping patients in motor recovery rehabilitation. One of the main limitations for the broad use of such devices is the high cost associated with the high-quality equipment used for capturing the biomedical signals. Different low-cost consumer-grade alternatives have emerged with the objective of bringing these systems closer to the final users. The quality of the signals obtained with such equipments has already been evaluated and found to be competitive with those obtained with well-known clinical-grade devices. However, how these consumer-grade technologies can be integrated and used for practical MI-BCIs has not yet been explored. In this work, we provide a detailed description of the advantages and disadvantages of using OpenBCI boards, low-cost sensors and open-source software for constructing an entirely consumer-grade MI-BCI system. An analysis of the quality of the signals acquired and the MI detection ability is performed. Even though communication between the computer and the OpenBCI board is not always stable and the signal quality is sometimes affected by ambient noise, we find that by means of a filter-bank based method, similar classification performances can be achieved with an MI-BCI built under low-cost consumer-grade devices as compared to when clinical-grade systems are used. By means of this work we share with the BCI community our experience on working with emerging low-cost technologies, providing evidence that an entirely low-cost MI-BCI can be built. We believe that if communication stability and artifact rejection are improved, these technologies will become a valuable alternative to clinical-grade devices.Fil: Peterson, Victoria. Universidad Nacional de Entre RĂ­os; ArgentinaFil: GalvĂĄn, Catalina MarĂ­a. Universidad Nacional del Litoral; ArgentinaFil: HernĂĄndez, Hugo. Universidad Nacional de Entre RĂ­os; ArgentinaFil: Spies, Ruben Daniel. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Santa Fe. Instituto de MatemĂĄtica Aplicada del Litoral. Universidad Nacional del Litoral. Instituto de MatemĂĄtica Aplicada del Litoral; Argentin

    Predicting mental imagery based BCI performance from personality, cognitive profile and neurophysiological patterns

    Get PDF
    Mental-Imagery based Brain-Computer Interfaces (MI-BCIs) allow their users to send commands to a computer using their brain-activity alone (typically measured by ElectroEncephaloGraphy— EEG), which is processed while they perform specific mental tasks. While very promising, MI-BCIs remain barely used outside laboratories because of the difficulty encountered by users to control them. Indeed, although some users obtain good control performances after training, a substantial proportion remains unable to reliably control an MI-BCI. This huge variability in user-performance led the community to look for predictors of MI-BCI control ability. However, these predictors were only explored for motor-imagery based BCIs, and mostly for a single training session per subject. In this study, 18 participants were instructed to learn to control an EEG-based MI-BCI by performing 3 MI-tasks, 2 of which were non-motor tasks, across 6 training sessions, on 6 different days. Relationships between the participants’ BCI control performances and their personality, cognitive profile and neurophysiological markers were explored. While no relevant relationships with neurophysiological markers were found, strong correlations between MI-BCI performances and mental-rotation scores (reflecting spatial abilities) were revealed. Also, a predictive model of MI-BCI performance based on psychometric questionnaire scores was proposed. A leave-one-subject-out cross validation process revealed the stability and reliability of this model: it enabled to predict participants’ performance with a mean error of less than 3 points. This study determined how users’ profiles impact their MI-BCI control ability and thus clears the way for designing novel MI-BCI training protocols, adapted to the profile of each user

    Application de la mĂ©thode des transformateurs saturĂ©s Ă  la mesure et rĂ©gulation du champ magnĂ©tique d'un spectromĂštre ÎČ Ă  double focalisation π √2 avec noyau de fer

    No full text
    On dĂ©crit un nouveau magnĂ©tomĂštre pour mesurer les champs magnĂ©tiques constants ou lentement variables dans l'intervalle de variation entre 10 -4 et 3 x 102 Oe. La prĂ©cision relative est supĂ©rieure Ă  2,5 X 10-5 entre 7 et 300 Oe. Le champ magnĂ©tique d'un spectromĂštre ÎČ Ă  double focalisation π √2 du type Siegbahn-Svartholm est stabilisĂ© par un servomĂ©canisme. On utilise comme signal d'erreur la diffĂ©rence entre une tension proportionnelle au champ d'induction magnĂ©tique et une tension de rĂ©fĂ©rence

    Calibration and Validation of Accelerometry using cut-points to Assess Physical Activity in Paediatric Clinical Groups: A Systematic Review

    Get PDF
    Regular physical activity is associated with physiological and psychosocial benefits in both healthy and clinical populations. However, little is known about tailoring the analysis of physical activity using accelerometers to the specific characteristics of chronic conditions. Whilst accelerometry is broadly used to assess physical activity, recommendations on calibration in paediatric clinical groups are warranted. The aim of this systematic review was to provide a critical overview of protocols used to calibrate accelerometry in children and adolescents with clinical conditions, as well as to develop recommendations for calibration and validation of accelerometry in such populations. The search was performed between March to July 2017 using text words and subject headings in six databases. Studies had to develop moderate-to-vigorous intensity physical activity (MVPA) cut-points for paediatric clinical populations to be included. Risk of bias was assessed using a specific checklist. A total of 540,630 titles were identified, with 323 full-text articles assessed. Five studies involving 347 participants aged 9 to 15 years were included. Twenty-four MVPA cut-points were reported across seven clinical conditions, 16 of which were developed for different models of ActiGraph, seven for Actical and one for Tritrac-R3D. Statistical approaches included mixed regression, machine learning and receiver operating characteristic analyses. Disease-specific MVPA cut-points ranged from 152 to 735 counts·15 s−1, with lower cut-points found for inherited muscle disease and higher cut-points associated with intellectual disabilities. The lower MVPA cut-points for diseases characterised by both ambulatory and metabolic impairments likely reflect the higher energetic demands associated with those conditions

    Good scientific practice in MEEG Research: Progress and Perspectives

    Get PDF
    Good Scientific Practice (GSP) refers to both explicit and implicit rules, recommendations, and guidelines that help scientists to produce work that is of the highest quality at any given time, and to efficiently share that work with the community for further scrutiny or utilization.For experimental research using magneto- and electroencephalography (MEEG), GSP includes specific standards and guidelines for technical competence, which are periodically updated and adapted to new findings. However, GSP also needs to be periodically revisited in a broader light. At the LiveMEEG 2020 conference, a reflection on GSP was fostered that included explicitly documented guidelines and technical advances, but also emphasized intangible GSP: a general awareness of personal, organizational, and societal realities and how they can influence MEEG research.This article provides an extensive report on most of the LiveMEEG contributions and new literature, with the additional aim to synthesize ongoing cultural changes in GSP. It first covers GSP with respect to cognitive biases and logical fallacies, pre-registration as a tool to avoid those and other early pitfalls, and a number of resources to enable collaborative and reproducible research as a general approach to minimize misconceptions. Second, it covers GSP with respect to data acquisition, analysis, reporting, and sharing, including new tools and frameworks to support collaborative work. Finally, GSP is considered in light of ethical implications of MEEG research and the resulting responsibility that scientists have to engage with societal challenges.Considering among other things the benefits of peer review and open access at all stages, the need to coordinate larger international projects, the complexity of MEEG subject matter, and today's prioritization of fairness, privacy, and the environment, we find that current GSP tends to favor collective and cooperative work, for both scientific and for societal reasons

    Spatiotemporal dynamics in human visual cortex rapidly encode the emotional content of faces

    Get PDF
    Recognizing emotion in faces is important in human interaction and survival, yet existing studies do not paint a consistent picture of the neural representation supporting this task. To address this, we collected magnetoencephalography (MEG) data while participants passively viewed happy, angry and neutral faces. Using time-resolved decoding of sensor-level data, we show that responses to angry faces can be discriminated from happy and neutral faces as early as 90 ms after stimulus onset and only 10 ms later than faces can be discriminated from scrambled stimuli, even in the absence of differences in evoked responses. Time-resolved relevance patterns in source space track expression-related information from the visual cortex (100 ms) to higher-level temporal and frontal areas (200-500 ms). Together, our results point to a system optimised for rapid processing of emotional faces and preferentially tuned to threat, consistent with the important evolutionary role that such a system must have played in the development of human social interactions
    • 

    corecore