Early repolarization electrocardiography pattern with unexplained syncope during training in a young black African non-elite athlete: An accidental finding?

Until recently it was generally thought that early repolarization is benign. But a recent article in the NEJM (Haissaguerre et al.) suggests that some persons with early repolarization may be at risk of life-threatening ventricular tachyarrhythmia. Unexplained syncope or sudden death occurs mostly during sleep. However, some cases of cardiac arrest during exertion have been reported. We report the case of a 39 year-old black African male with early repolarization pattern on electrocardiogram who regularly experienced dizziness (and one episode of transient loss of consciousness) exclusively while exercising. Detailed examination was normal. Under quinidine therapy, he experienced no further episodes. Increasingly reported cases of cardiac arrest in Africans, and significant prevalence of early repolarization in this population, have to be taken into account since the Haissaguerre et al. report. Further evidence of the lethal consequences of this syndrome are needed, bearing in mind that diagnostic tools for life-threatening arrhythmias are often scarce in sub-Saharan Africa

Paradoxical embolism following thromboaspiration of an arteriovenous fistula thrombosis: a case report

<p>Abstract</p> <p>Introduction</p> <p>Paradoxical embolism is an increasingly reported cause of arterial embolism. Several embolic sources have been described, but thrombosis of an arteriovenous fistula as a paradoxical emboligenic source has not, to the best of our knowledge, been reported.</p> <p>Case presentation</p> <p>A 50-year-old Caucasian woman received a renal graft for primary hyperoxaluria. After transplantation, she was maintained on daily hemodialysis. Thrombosis of her arteriovenous fistula occurred two weeks post-transplantation and was treated by thromboaspiration, which was partially successful. During a hemodialysis session immediately following thromboaspiration, she developed a coma with tetraplegia requiring intensive cardiorespiratory resuscitation. Brain magnetic resonance imaging revealed various hyperdense areas in the vertebrobasilar territory resulting from bilateral occlusion of posterior cerebral arteries. Transesophageal echocardiographic examination showed a patent foramen ovale, while pulse echography of the arteriovenous fistula revealed the persistence of extensive clots that were probably the embolic source. A paradoxical embolus through a patent foramen ovale was suggested because of the proximity of the neurological event to the thrombectomy procedure.</p> <p>Conclusions</p> <p>The risk of paradoxical embolism in a hemodialyzed patient with a patent foramen ovale deserves consideration and requires careful evaluation in situations of arteriovenous fistula thrombosis.</p

Modélisation de la chaîne d'acquisition d'une machine à mesurer tridimensionnelle

International audienceIssus de l'approche systémique, le concept de Groupe Fonctionnels permet de modéliser les problèmes présents dans l'industrie mécanique. Après l'avoir utilisé en cotation fonctionnelle et pour décrire le processus d'industrialisation, nous proposons de l'utiliser pour mettre en évidence les différents flux présents dans une machine à mesurer tridimensionnelle. Par une modélisation basée sur le concept de Groupe Fonctionnel, nous proposons la procédure de mise en route d'une machine à mesurer tridimensionnelle. L'application de cette procédure d'initialisation permet de maîtriser le pilotage de ce procédé de mesure. Nous mettons en évidence les actions élémentaires qui sont nécessaires à une utilisation optimale de la machine à mesurer tridimensionnelle. Mots clés: Machine à mesurer tridimensionnelle, approche systémique, acquisition des données. Abstract Born of the systemic approach, the functional group concept allows to model the current mechanical industry problems. After using it for functional measurement and to describe the industrialisation process, we suggest using it on order to display the different flows that exist in a Coordinate Measurement Machine (CMM). By a modeling based on the functional group concept, we propose to establish the CMM logout. The implementation of this initialisation procedure gives us a full control on the measurement drive. This, we show the essential operations needed to a well use of the CMM

Synthesis of nanocrystalline NiAl by mechanically activated self-propagating high-temperature synthesis and mechanically activated annealing process

The mechanically activated self-propagating high-temperature synthesis (MASHS) technique and the mechanically activated annealing process (M2AP) were used to produce NiAl intermetallic compound. Rietveld analysis of X-ray diffraction data was used to characterize the mechanically activated powders, MASHS and M2AP end-products. Two-phase (B2+L12) nickel aluminide intermetallic compounds were synthesized by the mechanically activated volume combustion synthesis (MASHS). A single phase B2 NiAl was formed when mechanically activated annealing process (M2AP) was performed. Starting from a mixture of elemental pure powders, both M2AP and MASHS milling processes lead to nanostructured powders. Structural analysis deduced from the Rietveld refinement of X-ray diffraction patterns of NiAl compounds synthesized by SHS after a milling of 6 h show the formation of β-NiAl phase with a cell parameter a = (0.2885 ± 1.2618 × 10−4) nm. The average crystallite size is D = (44.6421 ± 2.4263) nm and the microstrains values are close to those of metallic alloys τ = (0.2142 ± 1.6186 × 10−2)%. Finally, scanning electron microscopy (SEM) was carried out to characterize the microstructure of end-products

Fish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we can learn from stable isotope analysis

International audienceFish food-web structure of a southern Mediterranean lagoon (El Mellah Lagoon, Algeria): what we can learn from stable isotope analysi