Management of mechanical ventilation in acute severe asthma: practical aspects

Background: Acute severe asthma induces marked alterations in respiratory mechanics, characterized by acritical limitation of expiratory flow and aheterogeneous and reversible increase in airway resistance, resulting in premature airway closure, lung, and chest wall dynamic hyperinflation and high intrinsic PEEP. Discussion: These abnormalities increase the work of breathing and can lead to respiratory muscle fatigue and life-threatening respiratory failure, in which case mechanical ventilation is life-saving. When instituting mechanical ventilation in this setting, amajor concern is the risk of worsening lung hyperinflation (thereby provoking barotrauma) and inducing or aggravating hemodynamic instability. Guidelines for mechanical ventilation in acute severe asthma are not supported by strong clinical evidence. Controlled hypoventilation with permissive hypercapnia may reduce morbidity and mortality compared to conventional normocapnic ventilation. Profound pathological alterations in respiratory mechanics occur during acute severe asthma, which clinicians should keep in mind when caring for ventilated asthmatics. Conclusion: We focus on the practical management of controlled hypoventilation. Particular attention must be paid to ventilator settings, monitoring of lung hyperinflation, the role of extrinsic PEEP, and administering inhaled bronchodilators. We also underline the importance of deep sedation with respiratory drive-suppressing opioids to maintain patient-ventilator synchrony while avoiding as much as can be muscle paralysis and the ensuing risk of myopathy. Finally, the role of noninvasive positive pressure ventilation for the treatment of respiratory failure during severe asthma is discusse

Dexterous Grasping Tasks Generated With an Add-on End Effector of a Haptic Feedback System

The simulation of grasping operations in virtual reality (VR) is required for many applications, especially in the domain of industrial product design, but it is very difficult to achieve without any haptic feedback. Force feedback on the fingers can be provided by a hand exoskeleton, but such a device is very complex, invasive, and costly. In this paper, we present a new device, called HaptiHand, which provides position and force input as well as haptic output for four fingers in a noninvasive way, and is mounted on a standard force-feedback arm. The device incorporates four independent modules, one for each finger, inside an ergonomic shape, allowing the user to generate a wide range of virtual hand configurations to grasp naturally an object. It is also possible to reconfigure the virtual finger positions when holding an object. The paper explains how the device is used to control a virtual hand in order to perform dexterous grasping operations. The structure of the HaptiHand is described through the major technical solutions required and tests of key functions serve as validation process for some key requirements. Also, an effective grasping task illustrates some capabilities of the HaptiHand

Nonselective versus Selective Inhibition of Inducible Nitric Oxide Synthase in Experimental Endotoxic Shock

The effects of two nitric oxide synthase (NOS) inhibitors with different isoform selectivity were compared in a murine model of endotoxemia. Mice challenged with 70 mg/kg intraperitoneal (ip) lipopolysaccharide (LPS) were treated 6 h after LPS with either NG-γ-L-arginine methyl ester (LNAME, nonselective NOS inhibitor, 10-60 mg/kg), L-canavanine (selective inhibitor of inducible NOS, 50-300 mg/kg), or saline (0.2 mL) given ip. In a subset of mice, plasma concentrations of nitrate (NO breakdown product), lipase (pancreas injury), lactate dehydrogenase, and transaminases (liver injury) were measured 16 h after LPS. Although both inhibitors reduced plasma nitrate, they produced contrasting effects on survival and organ injury. L-NAME enhanced liver damage and tended to accelerate the time of death, while L-canavanine significantly reduced mortality and had no deleterious effects in terms of organ damage. These results indicate that nonselective NOS inhibitors are detrimental in endotoxic shock and support the potential usefulness of selective inducible NOS inhibitors in this settin

An add-on device to perform dexterous grasping tasks with a haptic feedback system

Achieving grasping tasks in real time with haptic feedback may require the control of a large number of degrees of freedom (DOFs) to model hand and finger movements. This is mandatory to grasp objects with dexterity. Here, a new device called HaptiHand is proposed that can be added to a haptic feedback arm and provide the user with enough DOFs so that he/she can intuitively and dexterously grasp an object, modify the virtual hand configuration and number of fingers with respect to the object while manipulating the object. Furthermore, this device is non-invasive and enables the user to apply forces on the fingers of the virtual hand. The HaptiHand lies inside the user’s hand so that the user can apply and release pressure on it in a natural manner that is transferred to the virtual hand using metaphors. The focus is placed on the description of the technology and structure of the HaptiHand to justify the choices and explain the behavior of the HaptiHand during object grasping and releasing tasks. This is combined with a short description of the models used.iLab Inria-Haptio

Disséminations expérimentales d’OGM en France et en Suisse : évolution du débat public Introduction

Bien que variable dans le temps et dans l’espace, le débat entourant la question des organismes génétiquement modifiés (OGM) est, depuis plusieurs années, très animé dans l’espace public européen. Si diverses études ont tenté d’analyser les différentes formes prises par le débat sur cette question en Europe et aux Etats-Unis sous forme d’études isolées et d’analyses comparées, la situation en Suisse n’a mobilisé que peu d’attention. Dans les deux premières parties de cet article, nous nous pr..

De la gestion à la négociation des risques : apports des procédures participatives d’évaluation des choix technologiques

1. Introduction Cet article traite de la manière dont l’approche classique en termes d’évaluation et de gestion des risques se trouve aujourd’hui mise en question, tant par l’émergence de nouveaux dangers qu’elle ne permet plus de contenir, que par le fait que ces dangers doivent être négociés dans le cadre d’une communauté d’acteurs sans cesse plus diversifiée. Nous décrirons tout d’abord le contexte dans lequel se manifeste désormais la question des risques technologiques. Nous partirons de..

Deficiency of the LIM-Only Protein FHL2 Reduces Intestinal Tumorigenesis in Apc Mutant Mice

BACKGROUND: The four and a half LIM-only protein 2 (FHL2) is capable of shuttling between focal adhesion and nucleus where it signals through direct interaction with a number of proteins including beta-catenin. Although FHL2 activation has been found in various human cancers, evidence of its functional contribution to carcinogenesis has been lacking. METHODOLOGY/PRINCIPAL FINDINGS: Here we have investigated the role of FHL2 in intestinal tumorigenesis in which activation of the Wnt pathway by mutations in the adenomatous polyposis coli gene (Apc) or in beta-catenin constitutes the primary transforming event. In this murine model, introduction of a biallelic deletion of FHL2 into mutant Apc(Delta14/+) mice substantially reduces the number of intestinal adenomas but not tumor growth, suggesting a role of FHL2 in the initial steps of tumorigenesis. In the lesions, Wnt signalling is not affected by FHL2 deficiency, remaining constitutively active. Nevertheless, loss of FHL2 activity is associated with increased epithelial cell migration in intestinal epithelium, which might allow to eliminate more efficiently deleterious cells and reduce the risk of tumorigenesis. This finding may provide a mechanistic basis for tumor suppression by FHL2 deficiency. In human colorectal carcinoma but not in low-grade dysplasia, we detected up-regulation and enhanced nuclear localization of FHL2, indicating the activation of FHL2 during the development of malignancy. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate that FHL2 represents a critical factor in intestinal tumorigenesis

Introduction à l'hygiène du travail : un support de formation

[Table des matières] A. Cadre et contexte général : Place et démarche de santé au travail ; Place de l'hygiène du travail dans la santé au travail ; Approche pluridisciplinaire et équipe de santé au travail ; Interface avec d'autres acteurs ; Gestion du risque ; Concept général ; Les outils du management ; La notion de risque acceptable. - B. Hygiène et sécurité du travail : Définition et historique de l'hygiène du travail ; Défis et perspectives ; Ethique professionnelle ; Démarche de l'hygiène du travail ; Méthode d'analyse des risques. - C. Identification des dangers : Méthodes ; Etiquetage des produits chimiques. - D. Evaluation des risques : Généralités ; Stratégie ; Normes ; Risques chimiques ; Toxicologie ; Gaz, vapeurs ; Aérosols ; Amiante ; Surveillance biologique ; Laboratoires ; Risques physiques ; Le Bruit ; Les vibrations ; Les radiations ionisantes ; Rayonnement optique et lasers ; Radiofréquence et rayonnements de basse fréquence ; Le stress thermique ; Environnements hypo- et hyperbares ; les risques biologiques ; Facteurs généraux liés à l'ambiance ; Aspects ergonomiques ; Généralités ; Charge physique ; Organisation du travail ; Instruments de mesure. - E. Maîtrise du risque : Organisation de la prévention ; Un nouveau concept de gestion du risque ; Prévention technique ; A la source - substitution ; A l'interface - ventilation ; Sur la cible. Equipements de protection individuelle ; Au niveau du travailleur - Prévention médicale ; Information et formation des travailleurs

Design of Portable and Accessible Platform in Charge of Wheelchair Feedback Immersion

Rewarded at Laval Virtual 2014, the AccesSim project aims to develop a wheelchair simulator based on Virtual Reality (VR) and a dynamic force­‐feedback platform, which allows to experience and to evaluate the accessibility in complex urban or property environment. In order to address this issue, the dynamic force-­feedback platform should provide haptic and vestibular feedback to various user profiles: from town‐planners to wheelchair users. The platform needs to be modular and adjustable to each of these profiles. This article focuses on the dynamic force­‐feedback platform and specifically on the force­‐feedback systems used.Ile‐De­‐France region, EDF R&D (project leader), LISV (UVSQ), LAMPA (Arts & Métiers ParisTech), CEREMH, CEA-­LIST