French Armed Forces Biomedical Research Institute IRBA

Marseille, France

French Armed Forces Biomedical Research Institute IRBA

Marseille, France
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Chennaoui M.,French Armed Forces Biomedical Research Institute IRBA | Chennaoui M.,University of Paris Pantheon Sorbonne | Arnal P.J.,French Armed Forces Biomedical Research Institute IRBA | Arnal P.J.,University of Paris Pantheon Sorbonne | And 8 more authors.
Frontiers in Neuroscience | Year: 2017

The purinergic type P1 (adenosine A1 and A2A) receptors and the type P2 (X7) receptor have been suggested to mediate physiological effects of adenosine and adenosine triphosphate on sleep. We aimed to determine gene expression of A1R (receptor), A2AR, and P2RX7 in leukocytes of healthy subjects during total sleep deprivation followed by sleep recovery. Expression of the pro-inflammatory cytokines IL-1β and TNF-α were also determined as they have been characterized as sleep regulatory substances, via P2RX7 activation. Blood sampling was performed on 14 young men (aged 31.9 ± 3.9) at baseline (B), after 24 h of sleep deprivation (24 h-SD), and after one night of sleep recovery (R). We compared gene expression levels after six nights of habitual (22.30-07.00) or extended (21.00-07.00) bedtimes. Using quantitative real-time PCR, the amount of mRNA for A1R, A2AR, P2RX7, TNF-α, and IL-1β was analyzed. After 24 h-SD compared to B, whatever prior sleep condition, a significant increase of A2AR expression was observed that returned to basal level after sleep recovery [day main effect, F(2, 26) = 10.8, p < 0.001]. In both sleep condition, a day main effect on P2RX7 mRNA was observed [F(2, 26) = 6.7, p = 0.005] with significant increases after R compared with 24 h-SD. TNF-α and IL-1β expressions were not significantly altered. Before 24 h-SD (baseline), the A2AR expression was negatively correlated with the latency of stage 3 sleep during the previous night, while that of the A1R positively. This was not observed after sleep recovery following 24 h-SD. This is the first study showing increased A2AR and not A1 gene expression after 24 h-SD in leukocytes of healthy subjects, and this even if bedtime was initially increased by 1.5 h per night for six nights. In conclusion, prolonged wakefulness induced an up-regulation of the A2A receptor gene expression in leukocytes from healthy subjects. Significant correlations between baseline expression of A1 and A2A receptors in peripheral cells and stage 3 sleep suggested their involvement in mediating the effects of adenosine on sleep. © 2017 Chennaoui, Arnal, Drogou, Leger, Sauvet and Gomez-Merino.


Tuiskunen A.,Karolinska Institutet | Tuiskunen A.,Swedish Institute for Communicable Disease Control | Tuiskunen A.,French Armed Forces Biomedical Research Institute IRBA | Monteil V.,French Armed Forces Biomedical Research Institute IRBA | And 10 more authors.
Archives of Virology | Year: 2011

Dengue viruses (DENV) cause 50-100 million cases of acute febrile disease every year, including 500,000 reported cases of dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Viral factors have been proposed to influence the severity of the disease, but markers of virulence have never been identified on DENV. Three DENV serotype-1 isolates from the 2007 epidemic in Cambodia that are derived from patients experiencing the various clinical forms of dengue were characterized both phenotypically and genetically. Phenotypic characteristics in vitro, based on replication kinetics in different cell lines and apoptosis response, grouped isolates from DF and DHF patients together, whereas the virus isolate from a DSS patient showed unique features: a lower level of replication in mammalian cells and extensive apoptosis in mosquito cells. Genomic comparison of viruses revealed six unique amino acid residues in the membrane, envelope, and in non-structural genes in the virus isolated from the DSS patient. © 2011 Springer-Verlag.


Lapole T.,Jean Monnet University | Temesi J.,Jean Monnet University | Temesi J.,University of Calgary | Arnal P.J.,Jean Monnet University | And 6 more authors.
Experimental Brain Research | Year: 2015

Soleus (SOL) corticospinal excitability has been reported to increase during Achilles tendon vibration. The aim of the present study was to further investigate SOL corticospinal excitability and elucidate the changes to intracortical mechanisms during Achilles tendon vibration. Motor-evoked potentials (MEPs) were elicited in the SOL by transcranial magnetic stimulation (TMS) of the corresponding motor cortical area of the leg with and without 50-Hz Achilles tendon vibration. SOL input–output curves were determined. Paired-pulse protocols were also performed to investigate short-interval intracortical inhibition (SICI) and intracortical facilitation (ICF) by conditioning test TMS pulses with sub-threshold TMS pulses at inter-stimulus intervals of 3 and 13 ms, respectively. During Achilles tendon vibration, motor threshold was lower than in the control condition (43 ± 13 vs. 49 ± 11 % of maximal stimulator output; p = 0.008). Input–output curves were also influenced by vibration, i.e. there was increased maximal MEP amplitude (0.694 ± 0.347 vs. 0.268 ± 0.167 mV; p < 0.001), decreased TMS intensity to elicit a MEP of half the maximal MEP amplitude (100 ± 13 vs. 109 ± 9 % motor threshold; p = 0.009) and a strong tendency for decreased slope constant (0.076 ± 0.04 vs. 0.117 ± 0.04; p = 0.068). Vibration reduced ICF (98 ± 61 vs. 170 ± 105 % of test MEP amplitude; p = 0.05), but had no effect on SICI (53 ± 26 vs. 48 ± 22 % of test MEP amplitude; p = 0.68). The present results further document the increased vibration-induced corticospinal excitability in the soleus muscle and suggest that this increase is not mediated by changes in SICI or ICF. © 2015, Springer-Verlag Berlin Heidelberg.


Bougard C.,French Armed Forces Biomedical Research Institute IRBA | Bougard C.,University of Paris Descartes | Bougard C.,Institute Of Recherche Biomedicale Des Armees Irba | Davenne D.,French Institute of Health and Medical Research | And 5 more authors.
Sleep Medicine Reviews | Year: 2016

In recent years, the role of "sleepiness at the wheel" in the occurrence of accidents has been increasingly highlighted with several national and international public health campaigns based on consensual research publications. However, one aspect of this phenomenon is rarely taken into account, i.e., the risk of sleep-induced accidents while riding powered two-wheelers (PTWs). PTWs are indeed involved in a high percentage of fatal accidents mostly with young male riders. The effects of sleepiness may be different in drivers and riders, partly because riders may be stimulated more by the road environment. But riders (differently from drivers) have also to maintain continuously a balance between their own stability and the need of following the road, even when they are directly exposed to adverse climatic conditions. We, therefore, gathered the limited scientific literature on this topic and tried to analyze how riders may be affected differently by sleepiness. Finally we provide some suggestions as to how this question may be better approached in the future. © 2015 Elsevier Ltd.


Prat N.J.,French Armed Forces Biomedical Research Institute IRBA | Prat N.J.,U.S. Army | Montgomery R.,U.S. Army | Cap A.P.,U.S. Army | And 4 more authors.
Shock | Year: 2015

Blast is one of the major causes of injury and death in recent armed conflicts. With increased use of improvised explosive devices in Iraq and Afghanistan, more than 71% of combat casualties are caused by explosions. Blast injuries can range from primary (caused by shock wave) to quaternary injuries (e.g., burns), and such injuries can result in an acute coagulopathy denoted by a hypocoagulable state. It is not clear if this coagulopathy observed in victims of explosion is caused by local or general effect of the primary blast injury itself. In this study, 13 pigs were subjected to severe isolated open-field blast injury and we measured indices of coagulation impairment during the first hour after injury: ROTEM, prothrombin time, activated partial thromboplastin time, coagulation factors, thrombin generation potential, platelet count, platelet activation, platelet function, and procoagulant microparticle formation. After 1 h, the mortality was 33%. No coagulation dysfunction was observed in the survivors in this period. This study presented a highly reproducible and consistent isolated blast injury in large mammals with comprehensive coagulation testing. The data suggest that isolated primary blast injury is not responsible for acute coagulopathy of trauma in victims of explosion but seems to lead to an early hypercoagulable state. Copyright © 2015 by the Shock Society.


Prat C.M.,French Armed Forces Biomedical Research Institute IRBA | Flusin O.,French Armed Forces Biomedical Research Institute IRBA | Panella A.,Centers for Disease Control and Prevention | Tenebray B.,French Armed Forces Biomedical Research Institute IRBA | And 2 more authors.
Emerging Infectious Diseases | Year: 2014

Chikungunya virus (CHIKV) is present or emerging in dengue virus–endemic areas. Infections caused by these viruses share some common signs/symptoms, but prognosis, patient care, and persistent symptoms differ. Thus, accurate diagnostic methods are essential for differentiating the infections. We evaluated 4 CHIKV serologic diagnostic tests, 2 of which showed poor sensitivity and specificity. © 2014, Centers for Disease Control and Prevention (CDC). All rights reserved.


Huguet L.,Compiègne University of Technology | Huguet L.,University Paris - Sud | Lourdeaux D.,Compiègne University of Technology | Sabouret N.,University Paris - Sud | Ferrer M.-H.,French Armed Forces Biomedical Research Institute IRBA
Studies in Health Technology and Informatics | Year: 2016

The VICTEAMS project aims at designing a virtual environment for training medical team leaders to non-technical skills. The virtual environment is populated with autonomous virtual agents who are able to make mistakes (in action or communication) in order to train rescue team leaders and to make them adaptive with all kinds of situations or teams. © 2016 The authors and IOS Press. All rights reserved.


Bougard C.,French Armed Forces Biomedical Research Institute IRBA | Bougard C.,University of Paris Descartes | Moussay S.,French Institute of Health and Medical Research | Moussay S.,University of Caen Lower Normandy | And 3 more authors.
Biological Rhythm Research | Year: 2016

The extent to which the diurnal fluctuations of different cognitive processes could be affected by sleep loss may be explored to predict performance decrements observed in the real world. Twenty healthy male subjects voluntarily took part in 8 test sessions at 06:00, 10:00, 14:00, and 18:00 h, following either a night with or without sleep in random order. Measurements included oral temperature, simple reaction time, sign cancelation, Go/NoGo, and the Purdue pegboard test. The results indicate that simple reaction time and motor coordination had morning–afternoon variations closely following the rhythms of temperature and vigilance. Inhibitory attention (Go/NoGo) presented no morning–afternoon variations. Sleep deprivation may affect the profiles of cognitive performance depending on the processes solicited. Sustained and inhibitory attention are particularly affected in the morning (after 24 and 28 waking hours), while a complex task (visuo-motor coordination) would be affected after 32 waking hours only. © 2016 Taylor & Francis


Chennaoui M.,French Armed Forces Biomedical Research Institute IRBA | Chennaoui M.,University of Paris Descartes | Drogou C.,French Armed Forces Biomedical Research Institute IRBA | Drogou C.,University of Paris Descartes | And 6 more authors.
European Cytokine Network | Year: 2014

Acute sleep deprivation in humans has been found to increase inflammatory markers and signaling pathways in the periphery through a possible Toll-like receptor 4 (TLR-4). In addition, short duration sleep has been associated with low circulating total Insulin-like Growth Factor-I (IGF-I) concentrations. We aimed to determine whether a total sleep deprivation (TSD) protocol with recovery altered whole-blood gene expression of the proinflammatory cytokines TNF-α and IL-6, as well as TLR-4 expression, and to examine the relationship with circulating concentrations of the IGF-I system. Twelve healthy men participated in a five-day TSD (two control nights followed by one night of sleep deprivation and one night of recovery). Blood was sampled at 0800, before and after sleep deprivation (D2 and D4), and after recovery (D5). It is shown that 25h of sleep deprivation (D4) induced significant increases in mRNA levels of TNF-α and its soluble receptor R1 (P<0.01 respectively), as well as TLR-4 (P<0.05), while IL-6 mRNA levels remained unchanged. Circulating concentrations of free IGF-I were decreased at D4 (P<0.001). One night of recovery was sufficient to restore basal expression levels for TNF-α, sTNF-R1, TLR-4 and circulating IGF-I. Changes in TLR-4 mRNA levels during the protocol correlated positively with those of TNF-α and sTNF-R1 (r = 0.393 and r = 0.490 respectively), and negatively with circulating free IGF-I (r =-0.494). In conclusion, 25h of sleep deprivation in healthy subjects is sufficient to induce transient and reversible genomic expression of the pro-inflammatory cytokine TNF-α and its R1 receptor, and its mediator TLR-4, with a possible link to IGF-I axis inhibition. © 2014 John Libbey Eurotext. All right reserved.

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