22 research outputs found
Syndromic surveillance and heat wave morbidity: a pilot study based on emergency departments in France
<p>Abstract</p> <p>Background</p> <p>The health impacts of heat waves are serious and have prompted the development of heat wave response plans. Even when they are efficient, these plans are developed to limit the health effects of heat waves. This study was designed to determine relevant indicators related to health effects of heat waves and to evaluate the ability of a syndromic surveillance system to monitor variations in the activity of emergency departments over time. The study uses data collected during the summer 2006 when a new heat wave occurred in France.</p> <p>Methods</p> <p>Data recorded from 49 emergency departments since July 2004, were transmitted daily via the Internet to the French Institute for Public Health Surveillance. Items collected on patients included diagnosis (ICD10 codes), outcome, and age. Statistical t-tests were used to compare, for several health conditions, the daily averages of patients within different age groups and periods (whether 'on alert' or 'off alert').</p> <p>Results</p> <p>A limited number of adverse health conditions occurred more frequently during hot period: dehydration, hyperthermia, malaise, hyponatremia, renal colic, and renal failure. Over all health conditions, the total number of patients per day remained equal between the 'on alert' and 'off alert' periods (4,557.7/day vs. 4,511.2/day), but the number of elderly patients increased significantly during the 'on alert' period relative to the 'off alert' period (476.7/day vs. 446.2/day p < 0.05).</p> <p>Conclusion</p> <p>Our results show the interest to monitor specific indicators during hot periods and to focus surveillance efforts on the elderly. Syndromic surveillance allowed the collection of data in real time and the subsequent optimization of the response by public health agencies. This method of surveillance should therefore be considered as an essential part of efforts to prevent the health effects of heat waves.</p
Comparative Dynamics of Retrograde Actin Flow and Focal Adhesions: Formation of Nascent Adhesions Triggers Transition from Fast to Slow Flow
Dynamic actin network at the leading edge of the cell is linked to the extracellular matrix through focal adhesions (FAs), and at the same time it undergoes retrograde flow with different dynamics in two distinct zones: the lamellipodium (peripheral zone of fast flow), and the lamellum (zone of slow flow located between the lamellipodium and the cell body). Cell migration involves expansion of both the lamellipodium and the lamellum, as well as formation of new FAs, but it is largely unknown how the position of the boundary between the two flow zones is defined, and how FAs and actin flow mutually influence each other. We investigated dynamic relationship between focal adhesions and the boundary between the two flow zones in spreading cells. Nascent FAs first appeared in the lamellipodium. Within seconds after the formation of new FAs, the rate of actin flow decreased locally, and the lamellipodium/lamellum boundary advanced towards the new FAs. Blocking fast actin flow with cytochalasin D resulted in rapid dissolution of nascent FAs. In the absence of FAs (spreading on poly-L-lysine-coated surfaces) retrograde flow was uniform and the velocity transition was not observed. We conclude that formation of FAs depends on actin dynamics, and in its turn, affects the dynamics of actin flow by triggering transition from fast to slow flow. Extension of the cell edge thus proceeds through a cycle of lamellipodium protrusion, formation of new FAs, advance of the lamellum, and protrusion of the lamellipodium from the new base
Rac3 induces a molecular pathway triggering breast cancer cell aggressiveness: differences in MDA-MB-231 and MCF-7 breast cancer cell lines
Développement de nouvelles structures de μDELs UV à effet de champ
The deep-UV, a strong germicide, is used in particular in water purification centers employing mercury lamps. Nonetheless, the use of mercury is increasingly controversial and may be banned in the next years. Therefore, new deep-UV emitters are being considered, such as deep-UV LEDs (Light Emitting Diodes). In order to create a LED emitting at a wavelength close to 265nm, where the germicide effect is optimal, a ternary material is used : the AlxGa1-xN, with a high aluminium concentration. However, this material is not mastered yet, and p-doping it is very complicated.To avoid this doping issue, an innovative UV-LED structure has been imagined : the field effect LED, using a gate to ease the insertion of holes in the active area. In this thesis work, this component is analysed and developed. Simulations highlighted the relevance of such a LED compared to a standard DEL, with a surprising evolution of the WPE (Wall Plug Efficiency).Simulations testing the robustness of the experimental device brought to light the fact that such a technology requires the mesa’s side surface not to be damaged by the laser engraving. Hence, a survey studying multiple characterisation tools such as MET, atom probe, Auger spectroscopy or even cathodoluminescence has been realised. An electrical test was developed in order to identify the nature of the etching defects, and limit them.This work identified low damaging etching process, and field effect LED were developed. Electro-optical characterisations of these components were made, in order to enlighten the impact of the gate on the electroluminescence.L’UV profond a un pouvoir germicide, utilisé notamment dans des centres de purification de l’eau via l’emploi de lampes à mercure. L’utilisation du mercure est cependant de plus en plus controversée et en voie d’être complètement interdite. De nouveaux systèmes de désinfection sont à l’étude tels que les DELs-UV (diode électroluminescente émettant dans l’ultraviolet). Pour créer une DEL émettant à une longueur d’onde proche de 265 nm, où le pouvoir germicide est optimal, il faut utiliser un matériau ternaire l’AlxGa1−xN avec une forte concentration d’aluminium. Ce matériau est aujourd’hui peu maitrisé, et particulièrement compliqué à doper de type p.Afin de contourner ce problème de dopage, une structure novatrice de DEL-UV, utilisant une grille pour faciliter l’insertion des trous dans la zone active, a été imaginée : la DEL à effet de champ. Dans ce travail de thèse nous analysons et réalisons ce composant. Des simulations ont permis de mettre en évidence l’intérêt d’une telle DEL vis à vis d’une DEL standard, avec entre autre une évolution surprenante du rendement WPE (Wall Plug Efficiency). Suite à des simulations testant la robustesse du dispositif, il est apparu qu’une telle technologie nécessite que la gravure de la mesa n’endommage pas la surface latérale de cette dernière. C’est pourquoi une étude croisant différents outils de caractérisation tels que le TEM, la sonde tomographique atomique, la spectroscopie Auger, ou encore la cathodoluminescence a été réalisée. Un test électrique a été mis au point afin d’identifier la nature des défauts de gravure et de les limiter.Ce travail a permis d’identifier un procédé de gravure peu endommageant et des DELs à effet de champ ont été réalisées. Des caractérisations électro-optiques de ces composants ont été menées afin de mettre en évidence l’impact de la grille sur l’électroluminescence
New field effect UV μLEDs development
L’UV profond a un pouvoir germicide, utilisé notamment dans des centres de purification de l’eau via l’emploi de lampes à mercure. L’utilisation du mercure est cependant de plus en plus controversée et en voie d’être complètement interdite. De nouveaux systèmes de désinfection sont à l’étude tels que les DELs-UV (diode électroluminescente émettant dans l’ultraviolet). Pour créer une DEL émettant à une longueur d’onde proche de 265 nm, où le pouvoir germicide est optimal, il faut utiliser un matériau ternaire l’AlxGa1−xN avec une forte concentration d’aluminium. Ce matériau est aujourd’hui peu maitrisé, et particulièrement compliqué à doper de type p.Afin de contourner ce problème de dopage, une structure novatrice de DEL-UV, utilisant une grille pour faciliter l’insertion des trous dans la zone active, a été imaginée : la DEL à effet de champ. Dans ce travail de thèse nous analysons et réalisons ce composant. Des simulations ont permis de mettre en évidence l’intérêt d’une telle DEL vis à vis d’une DEL standard, avec entre autre une évolution surprenante du rendement WPE (Wall Plug Efficiency). Suite à des simulations testant la robustesse du dispositif, il est apparu qu’une telle technologie nécessite que la gravure de la mesa n’endommage pas la surface latérale de cette dernière. C’est pourquoi une étude croisant différents outils de caractérisation tels que le TEM, la sonde tomographique atomique, la spectroscopie Auger, ou encore la cathodoluminescence a été réalisée. Un test électrique a été mis au point afin d’identifier la nature des défauts de gravure et de les limiter.Ce travail a permis d’identifier un procédé de gravure peu endommageant et des DELs à effet de champ ont été réalisées. Des caractérisations électro-optiques de ces composants ont été menées afin de mettre en évidence l’impact de la grille sur l’électroluminescence.The deep-UV, a strong germicide, is used in particular in water purification centers employing mercury lamps. Nonetheless, the use of mercury is increasingly controversial and may be banned in the next years. Therefore, new deep-UV emitters are being considered, such as deep-UV LEDs (Light Emitting Diodes). In order to create a LED emitting at a wavelength close to 265nm, where the germicide effect is optimal, a ternary material is used : the AlxGa1-xN, with a high aluminium concentration. However, this material is not mastered yet, and p-doping it is very complicated.To avoid this doping issue, an innovative UV-LED structure has been imagined : the field effect LED, using a gate to ease the insertion of holes in the active area. In this thesis work, this component is analysed and developed. Simulations highlighted the relevance of such a LED compared to a standard DEL, with a surprising evolution of the WPE (Wall Plug Efficiency).Simulations testing the robustness of the experimental device brought to light the fact that such a technology requires the mesa’s side surface not to be damaged by the laser engraving. Hence, a survey studying multiple characterisation tools such as MET, atom probe, Auger spectroscopy or even cathodoluminescence has been realised. An electrical test was developed in order to identify the nature of the etching defects, and limit them.This work identified low damaging etching process, and field effect LED were developed. Electro-optical characterisations of these components were made, in order to enlighten the impact of the gate on the electroluminescence
Prise en charge de l'accident vasculaire cérébral au service d'accueil des urgences du centre hospitalier de Mulhouse (améliorations et perspectives, à propos d'une étude rétrospective de deux séries de cas.)
STRASBOURG-Medecine (674822101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Unité d'hospitalisation de courte durée du centre hospitalier de Mulhouse (analyse - état des lieux et conformité aux recommandations de la SFMU. Perspectives d'avenir.)
STRASBOURG-Medecine (674822101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Les douleurs abdominales aux urgences (à propos de la prise en charge de deux cas d'adénomatose hépatique)
STRASBOURG-Medecine (674822101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF
Transient Activations of Rac1 at the Lamellipodium Tip Trigger Membrane Protrusion
International audienceThe spatiotemporal coordination of actin regulators in the lamellipodium determines the dynamics and architecture of branched F-actin networks during cell migration. The WAVE regulatory complex (WRC), an effector of Rac1 during cell protrusion, is concentrated at the lamellipodium tip. Thus, activated Rac1 should operate at this location to activate WRC and trigger membrane protrusion. Yet correlation of Rho GTPase activation with cycles of membrane protrusion previously revealed complex spatiotemporal patterns of Rac1 and RhoA activation in the lamellipodium. Combining single protein tracking (SPT) and super-resolution imaging with loss- or gain-of-function mutants of Rho GTPases, we show that Rac1 immobilizations at the lamellipodium tip correlate with its activation, in contrast to RhoA. Using Rac1 effector loop mutants and wild-type versus mutant variants of WRC, we show that selective immobilizations of activated Rac1 at the lamellipodium tip depend on effector binding, including WRC. In contrast, wild-type Rac1 only displays slower diffusion at the lamellipodium tip, suggesting transient activations. Local optogenetic activation of Rac1, triggered by membrane recruitment of Tiam1, shows that Rac1 activation must occur close to the lamellipodium tip and not behind the lamellipodium to trigger efficient membrane protrusion. However, coupling tracking with optogenetic activation of Rac1 demonstrates that diffusive properties of wild-type Rac1 are unchanged despite enhanced lamellipodium protrusion. Taken together, our results support a model whereby transient activations of Rac1 occurring close to the lamellipodium tip trigger WRC binding. This short-lived activation ensures a local and rapid control of Rac1 actions on its effectors to trigger actin-based protrusion
Effects of inhibition of NADPH oxidase by apocynin, xanthine oxidase by allopurinol and mitochondrial complex I by rotenone on actinomycin D-induced apoptosis in pancreatic (CFPAC-1) and tracheal (CFT-2) cystic fibrosis cells (n = 5).
<p>Data are expressed in percentage of inhibition of actinomycin D-induced apoptosis.</p><p>*<i>p</i><0.05.</p