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Background: The epidemiology of meningococcal meningitis in the African meningitis belt is characterised by seasonality, localised epidemics and epidemic waves. To facilitate research and surveillance, we aimed to develop a definition for localised epidemics to be used in real-time surveillance based on weekly case reports at the health centre level.Methods: We used national routine surveillance data on suspected meningitis from January 2004 to December 2008 in six health districts in western and central Burkina Faso. We evaluated eight thresholds composed of weekly incidence rates at health centre level for their performance in predicting annual incidences of 0.4%and 0.8% in health centre areas. The eventually chosen definition was used to describe the spatiotemporal epidemiology and size of localised meningitis epidemics during the included district years.Results: Among eight weekly thresholds evaluated, a weekly incidence rate of 75 cases per 100,000 inhabitants during at least two consecutive weeks with at least 5 cases per week had 100% sensitivity and 98% specificity for predicting an annual incidence of at least 0.8% in health centres. Using this definition, localised epidemics were identified in all but one years during 2004-2008, concerned less than 10% of the districts' population and often were geographically dispersed. Where sufficient laboratory data were available, localised epidemics were exclusively due to meningococci.Conclusions: This definition of localised epidemics a the health centre level will be useful for risk factor and modelling studies to understand the meningitis belt phenomenon and help documenting vaccine impact against epidemic meningitis where no widespread laboratory surveillance exists for quantifying disease reduction after vaccination. © 2012 Tall et al; licensee BioMed Central Ltd. info:eu-repo/semantics/published SCOPUS: ar.j

International audience

International audience

A new Bg/II satellite DNA has been isolated, cloned and sequenced from the coffee root-knot nematode, Meloidogyne exigua (Nematoda: Tylenchida). It is represented as tandemly repeated sequences with a monomeric unit of 277 bp. The monomers are present at approximately 17 900 copies per haploid genome, and represent about 9.7% of the total genomic DNA. Twenty randomly chosen monomers have been sequenced. The deduced unambiguous consensus sequence is 277 bp long, and displays an A + T content of 54.2%. The monomers are very homogenous in sequence, showing on average 2.4% divergence from their consensus. Therefore, it is hypothesized that this repeated family may have recently appeared in the genome of the nematode, through some extensive amplification burst. Using a cloned monomer as a probe, dot-blot experiments demonstrated the species-specific distribution of the Bg/II satellite DNA. Moreover, squash-blot assays allowed us to detect single M. exigua individuals, at any developmental stage, and even within root tissues, without the need for preliminary DNA purification. From these results, it is concluded that the procedure described, using the satellite DNA as a sensitive species-specific probe, should constitute an improved and accurate diagnosis method for the detection and identification of the nematode, which would contribute to the implementation of targeted pest management strategies in all coffee growing countries of South and Central America.

International audience; Cannabis exposure during the perinatal period results in varied and significant consequences in affected offspring. The prevalence of detrimental outcomes of perinatal cannabis exposure is likely to increase in tandem with the broadening of legalization and acceptance of the drug. As such, it is crucial to highlight the immediate and protracted consequences of cannabis exposure on pre-and post-natal development. Here, we identify lasting changes in neurons' learning flexibility (synaptic plasticity) and epigenetic misregulation in animal models of perinatal cannabinoid exposure (using synthetic cannabinoids or active components of the cannabis plant) in addition to significant alterations in social behavior and executive functions. These findings are supported by epidemiological data indicating similar behavioral outcomes throughout life in human offspring exposed to cannabis during pregnancy. Further, we indicate important lingering questions regarding accurate modeling of perinatal cannabis exposure as well as the need for sex-and agedependent outcome measures in future studies.

1. In areas of intensive animal production heavy metals such as zinc (Zn), which is present at high concentrations in poultry excreta in relation to plant requirements, may be at the origin of soil phytotoxicity This study was conducted in order to determine the effect of decreasing dietary Zn content on growth, plasma, tibia and whole body Zn concentrations, immune function, enzyme activity, Zn body retention and Zn concentration in excreta in broilers. 2. Two experiments were carried out using 160 and 80 1-day-old chicks. Broilers received diets with increased Zn contents of 20 to 190 mg/kg. In experiment 1, two sources of zinc methionine were compared to zinc sulphate. 3. A dietary Zn concentration of 45 mg/kg was sufficient to obtain normal broiler performance at 21 d of age. 4. Tibia and plasma Zn concentrations increased linearly with Zn dietary content and reached a plateau at 75 mg/kg, whereas the whole body Zn was saturated when the dietary Zn content was 90 mg/kg. 5. Antibody titres in response to SRBC injection and plasma alkaline phosphatase activity were not affected by dietary zinc concentration. 6. When the dietary Zn content was decreased from 190 to 65 mg/kg, body Zn retention was increased from 8% to 20% and Zn concentration in broiler manure was reduced by 75%. 7. Zn sources had no effect on the parameters measured in this study. 8. A nutritional approach, that is by lowering dietary Zn supplementation may reduce the risks of phytotoxicity in the soil resulting from excessive Zn concentration in manure.

International audience; Human mitoNEET (mNT) is the first identified Fe−S protein of the mammalian outer mitochondrial membrane. Recently, we demonstrated the involvement of mNT in a specific cytosolic pathway dedicated to the reactivation of oxidatively damaged cytosolic aconitase by cluster transfer. In vitro studies using apo-ferredoxin (FDX) reveal that mNT uses an Fe-based redox switch mechanism to regulate the transfer of its cluster. Using the "gold standard" cluster recipient protein, FDX, we show that this transfer is direct and that only one of the two mNT clusters is transferred when the second one is decomposed. Combining complementary biophysical and biochemical approaches, we show that pH affects both the sensitivity of the cluster to O 2 and dimer stability. Around physiological cytosolic pH, the ability of mNT to transfer its cluster is tightly regulated by the pH. Finally, mNT is extremely resistant to H 2 O 2 compared to ISCU and SufB, two other Fe−S cluster transfer proteins, which is consistent with its involvement in a repair pathway of stress-damaged Fe−S proteins. Taken together, our results suggest that the ability of mNT to transfer its cluster to recipient proteins is not only controlled by the redox state of its cluster but also tightly modulated by the pH of the cytosol. We propose that when pathophysiological conditions such as cancer and neurodegenerative diseases dysregulate cellular pH homeostasis, this pH-dependent regulation of mNT is lost, as is the regulation of cellular pathways under the control of mNT. I ron−sulfur (Fe−S) clusters are evolutionarily ancient and highly conserved prosthetic cofactors. Composed of only iron and sulfur, they are involved in many essential biological processes. 1,2 MitoNEET (mNT), also known as CISD1, is the first identified Fe−S protein of the mammalian outer mitochondrial membrane (OMM). 3,4 This is a small homodimeric protein (13 kDa for each monomer) anchored to the OMM by its 32-amino acid N-terminus with the major part of the protein, including the C-terminal Fe−S binding domain, located in the cytosol. 4 Each monomer accommodates one [2Fe-2S] cluster coordinated by three cysteines (C72, C74, and C83) and one histidine (H87) in a CDGSH domain 5−8 as other members of the NEET protein family, 9 which also includes Miner1 (or CISD2) and Miner2 (or CISD3) in mammals. 10 Although the biological activity of mNT is still debated, 11 studies have shown that it is involved in the regulation of iron/reactive oxygen species homeo-stasis, 12−14 in the regulation of lipid and glucose metabolism , 13,15 and in cell proliferation in breast cancer. 16 In vitro studies revealed that holo-mNT (the form of the protein with the cluster) is able to transfer its Fe−S cluster to very diverse apoprotein (an Fe−S protein, which has lost its cluster) recipients assembling either a [2Fe-2S] cluster as ferredoxin from various organisms, 17,18 human anamorsin 19 and CISD2, 20 or a [4Fe-4S] cluster as mammalian iron regulatory protein-1 (IRP-1)/cytosolic aconitase (c-aconi-tase). 14 On the basis of in cellulo experiments, we showed that mNT is able to repair the oxidatively damaged Fe−S cluster of human IRP-1/c-aconitase by transferring its cluster to the damaged protein. 14 Recently, we started to investigate in depth the in vitro cluster transfer reaction, focusing on the transfer from holo-mNT to [2Fe-2S] recipient protein. We unambiguously demonstrated that oxidized mNT ([2Fe-2S] 2+) triggers cluster transfer, whereas reduction of its cluster abrogates this transfer. Moreover, while O 2 significantly affects the lability of the oxidized mNT cluster, it does not interfere with the cluster

The roughness noise, radiated from the contact area of two sliding and rough solids under light load, is a complex phenomenon dependent on several parameters whose surface roughness, sliding speed, normal load and rubbed materials. Roughness noise differs from the other types of friction noise by a wide band spectrum, low noise levels, light contact pressure and therefore a weak dynamic coupling between sliding solids. Experimental and numerical approaches have been developed to study this type of noise. The experimental approach allowed to establish the variation laws of sound and vibration levels versus surface roughness and sliding speed. The numerical analysis is concerned with the local dynamic multicontact interfaces study. It provides access to parameters inaccessible to measurement (local forces, duration of inter-asperities shocks, frequency shocks) and allows a comparison with the sound and vibration measurements. Both experimental and numerical results show that roughness noise is simultaneously an increasing function of surface roughness and sliding speed. Three fundamental steps are involved in roughness noise phenomenon: tribology (vibrations are generated by the variations of the contact loads in the interface following the inter-asperities shocks), dynamics (propagation of the vibrations in the solids in contact) and acoustics (roughness noise is radiated by the solid surfaces). Therefore, the fundamental mechanism of roughness noise is the presence of shocks occurring between antagonist asperities of sliding surfaces. These shocks are characterized by their frequency, their duration and their percussion. The frequency decreases as the roughness or the sliding speed increases. The percussion is an increasing function of roughness and sliding speed and the shock duration is independent of the surface roughness and the sliding speed.; Le bruit de rugosité, rayonné lors du frottement entre surfaces rugueuses sous faible chargement, est un phénomène complexe dépendant de plusieurs paramètres dont la rugosité de surface, la vitesse de glissement, le chargement normal appliqué et les matériaux frottés. Il se distingue des autres types du bruit de frottement par un spectre fréquentiel large bande, un niveau sonore faible, une faible pression de contact et par conséquent un couplage dynamique faible entre les solides en contact. Pour étudier ce type du bruit, deux approches ont été développées: expérimentale et numérique. L'approche expérimentale a permis de proposer des lois de variation des niveaux sonores et vibratoires en fonction des paramètres tribologiques (principalement la rugosité) et cinématique (principalement la vitesse de glissement). L'approche numérique est consacrée à l'étude de la dynamique locale des interfaces multicontact. Elle a permis ainsi d'accéder aux paramètres inaccessibles à la mesure (forces locales, durée de chocs inter-aspérités, fréquence de chocs) et d'établir une comparaison avec les mesures sonores et vibratoires. Les résultats aussi bien expérimentaux que numériques montrent que le bruit de rugosité est une fonction croissante de la rugosité de surface et de la vitesse de glissement. La phénoménologie du bruit de rugosité fait appel à trois disciplines différentes: la tribologie (génération des vibrations à l'interface multicontact dues aux variations des efforts de contact suite aux chocs inter-aspérités), la dynamique (propagation de ces vibrations dans les solides en contact) et l'acoustique (une partie de ces vibrations est dissipée sous forme de bruit de rugosité). Le mécanisme fondamental du bruit de rugosité est ainsi la mise en vibration des solides en contact générée par les chocs inter-aspérités. Ces chocs sont caractérisés par leur fréquence, leur percussion et leur durée. La fréquence diminue quand la rugosité ou la vitesse de glissement augmente, la percussion augmente avec ces deux paramètres et la durée de choc est indépendante de la rugosité de surface et la vitesse de glissement.

Background & Aims To determine the characteristics of hepatitis C (HCV)-infected patients in 2010 and compare this survey with those reported in 1995 and 2001. Patients and methods Observational multicentre study conducted in 2010 in French internal medicine, infectious diseases and hepatology departments. Results A total of 1621 HCV infected patients (mean age 50.1 ± 10.7 years; sex ratio M/F 1.8; genotype 1: 55.7%) were included. Of these, 910 (56.1%) were HIV–HCV co-infected, 463 (40.4%) were asymptomatic and 184 (16.1%) had cirrhosis at inclusion in this study. Positive viraemia was found in 1,025 patients (65.5%) at inclusion in this study. A complete pretreatment evaluation including investigation for HCV RNA, genotype determination and liver fibrosis was performed in 96.5, 80.5 and 68.7% of the 1,621 patients respectively. Previous and ongoing HCV treatments were noted in 49.6% and 20.1% of patients respectively. A sustained virological response (SVR) was observed in 271/801 (38.3%) patients, i.e. 44.1% and 30.7% in co-infected and mono-infected patients respectively. Cirrhosis was more frequent in the 2010 than in the 2001 and 1995 surveys (16.1% vs. 10.4% and 7.4% respectively; P < 0.0001). A complete pretreatment evaluation was performed in 57.9% and 50.9% of patients in 2010 and 2001 (P < 0.0001). Liver fibrosis evaluation was more frequent in 2010 than in the 2001 and 1995 surveys (68.7% vs. 62.7% and 28.7%, respectively, P < 0.0001). Conclusion The care of HCV-infected patients has changed significantly in ‘real life’ through an improvement of pretreatment evaluation before the antiviral introduction and the increased use of antivirals. New HCV therapy combinations including protease inhibitors are warranted to increase the SVR rate.

This work deals with optical electronic travel aids for visually impaired people. Initially, two devices allowing the detection of an unrestricted path were developed at the Aime Cotton Laboratory: the "Tom Pouce" and the "Télétact". The "Tom Pouce" is simple to use but presents limitations for detecting narrow passages at distances over three meters as well as avoiding fine posts. The "Télétact" allows users to manage every situation but the number of users is restricted due to the cognitive effort required.The main purpose of this thesis is to improve the sensors as well as the way the spatial information is transmitted to the user to allow the safe detection of all passages with reduced cognitive effort.First, the hypothesis is that the ideal protection zone could be a cylindrical shape. The approached realization of the cylindrical shape with infrared sensors is theoretically analyzed and experimentally tested. Two devices,"Tom Pouce II" and "Minitact”, using this concept were proposed to visually impaired people already using the “Tom Pouce I”. They greatly appreciated the improvement.Second, the laser telemetric laser sensors of the «Télétact» were modified to improve their performance and to reduce the sensitivity of mechanical constraints during daily use. The association of infrared sensors and laser telemetric sensors allowed the management of all kinds of passages, including chicanes, with a tactile interface having only three levels of alert corresponding to three zones of protection (less than 2 meters deep and 10 cm wide, between 2 and 6 meters deep and about 50 cm wide, and more than 6m deep and 1m wide). The cognitive effort is greatly reduced compared to the initial "Télétact" , which used 32 different sounds.Third, tools to objectively analyze the performance of the implemented devices in controlled environments were developed to finely adjust the shape of the protection zones.The last point dealt with the possibilities of identification of obstacles, imagery is explored but it is proved to be premature. Nowadays only tricks of the trade are effectively working.; Ce travail traite des aides optroniques aux déplacements des non-voyants. Préalablement à ce travail, deux « détecteurs de passage » ont été développés au Laboratoire Aimé Cotton le « Tom Pouce » et le « Télétact ». Le « Tom Pouce » est simple d’utilisation mais présente des limitations pour détecter les passages étroits à des distances supérieures à trois mètres ainsi que pour éviter les poteaux fins. Le « Télétact » permet de gérer l’ensemble des situations mais le nombre d’utilisateurs est limité par l’effort cognitif important que demande son utilisation ainsi que sa fragilité.Le but principal de cette thèse est d’améliorer les capteurs ainsi que leur façon de représenter l’espace afin d’avoir un dispositif facile d’utilisation détectant tous les passages.Dans un premier temps, l’hypothèse que la forme de la zone de protection idéale devrait être d’aspect cylindrique est émise. La réalisation approchée de cette forme à partir de capteurs infrarouges est analysée théoriquement et validée expérimentalement. Deux dispositifs le « Tom Pouce II » et le « Minitact » utilisant ce concept ont été proposés à des non-voyants et ont reçu un accueil favorable. Dans un second temps, les capteurs laser télémétriques du « Télétact » ont été revus afin d’améliorer leurs performances permettant entre autres une moindre sensibilité aux contraintes mécaniques. Une nouvelle forme d’association des capteurs infrarouges et laser permet de gérer l’ensemble des configurations de passages, y compris en chicane, avec une interface tactile ayant seulement trois niveaux d’alerte correspondant à trois zones de protection (moins de 2 mètres de profondeur sur 10 cm de large, entre 2 et 6 mètres sur plus de 50 cm de large, plus de 6m de profondeur et 1m de large ) avec un effort cognitif très réduit par rapport au « Télétact » initial utilisant 32 sons différents. Des outils pour pouvoir analyser objectivement les performances des dispositifs dans des environnements contrôlés ont été mis au point afin de pouvoir ajuster finement les formes des zones de protection. Un dernier point concerne les possibilités d’identification des obstacles, l’imagerie est explorée mais s’avère immature, actuellement seules les « astuces d’utilisation » des capteurs sont opérationnelles.