26 results on '"Frédéric Jacq"'
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2. The Aculeata of French Polynesia. III. Sphecidae, with the record of three new species for the Society Islands (Hymenoptera)
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Frédéric Jacq, Sylvain Charlat, Thibault Ramage, Génétique et évolution des interactions hôtes-parasites, Département génétique, interactions et évolution des génomes [LBBE] (GINSENG), Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)-Laboratoire de Biométrie et Biologie Evolutive - UMR 5558 (LBBE), and Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-VetAgro Sup - Institut national d'enseignement supérieur et de recherche en alimentation, santé animale, sciences agronomiques et de l'environnement (VAS)-Centre National de la Recherche Scientifique (CNRS)
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Sphecidae ,Sceliphron caementarium ,Ecology ,Fauna ,French Polynesia ,Sceliphron ,Chalybion ,identification key ,New Caledonia ,Wallis and Futuna ,Identification key ,Biology ,[SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy ,biology.organism_classification ,Taxonomy (biology) ,Sceliphron laetum - Abstract
The sphecid fauna of French Polynesia, limited until now to Sceliphron caementarium (Drury), is increased by three species recently introduced in the Society Islands : Sceliphron laetum (Smith), S. curvatum (Smith) and Chalybion bengalense (Dahlbom). The presence of S. curvatum in French Polynesia considerably broadens the known distribution of this species which is native to Asia and introduced into Europe and both North and South America. Chalybion bengalense is also reported from New Caledonia for the first time, as well as Sceliphron laetum from Wallis and Futuna. The distribution, biology and potential impact of each species on the arachnofauna are discussed. An identification key to the Sphecidae of French Polynesia is provided., Les Aculéates de Polynésie française. III. Les Sphecidae, avec le premier signalement de trois espèces pour les îles de la Société (Hymenoptera). La faune des Sphecidae de Polynésie française, limitée jusqu’à présent à Sceliphron caementarium (Drury), est ici augmentée de trois espèces récemment introduites dans les îles de la Société : Sceliphron laetum (Smith), S. curvatum (Smith) et Chalybion bengalense (Dahlbom). La présence de S. curvatum en Polynésie française agrandit considérablement la répartition connue de cette espèce originaire d’Asie et introduite en Europe comme aux Amériques. Chalybion bengalense est également cité de Nouvelle-Calédonie pour la première fois, de même que Sceliphron laetum de Wallis-et-Futuna. La distribution, la biologie, ainsi que l’impact potentiel de chaque espèce sur l’arachnofaune sont précisés. Une clé d’identification est proposée, permettant de distinguer l’ensemble des espèces présentes sur le territoire., Ramage Thibault, Charlat Sylvain, Jacq Frédéric. The Aculeata of French Polynesia. III. Sphecidae, with the record of three new species for the Society Islands (Hymenoptera). In: Bulletin de la Société entomologique de France, volume 120 (2),2015. pp. 157-163.
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- 2015
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3. Neuroevolution Application to Collaborative and Heuristics-Based Connected and Autonomous Vehicle Cohort Simulation at Uncontrolled Intersection
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Frederic Jacquelin, Jungyun Bae, Bo Chen, and Darrell Robinette
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optimal control ,intelligent systems ,artificial intelligence ,Neuroevolution ,uncontrolled intersection ,minimum energy control ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Artificial intelligence is gaining tremendous attractiveness and showing great success in solving various problems, such as simplifying optimal control derivation. This work focuses on the application of Neuroevolution to the control of Connected and Autonomous Vehicle (CAV) cohorts operating at uncontrolled intersections. The proposed method implementation’s simplicity, thanks to the inclusion of heuristics and effective real-time performance are demonstrated. The resulting architecture achieves nearly ideal operating conditions in keeping the average speeds close to the speed limit. It achieves twice as high mean speed throughput as a controlled intersection, hence enabling lower travel time and mitigating energy inefficiencies from stop-and-go vehicle dynamics. Low deviation from the road speed limit is hence continuously sustained for cohorts of at most 50 m long. This limitation can be mitigated with additional lanes that the cohorts can split into. The concept also allows the testing and implementation of fast-turning lanes by simply replicating and reconnecting the control architecture at each new road crossing, enabling high scalability for complex road network analysis. The controller is also successfully validated within a high-fidelity vehicle dynamic environment, showing its potential for driverless vehicle control in addition to offering a new traffic control simulation model for future autonomous operation studies.
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- 2023
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4. Pandanus papateaensis (Pandanaceae): une nouvelle espèce menacée de l’atoll soulevé de Makatea (Tuamotu, Polynésie française)
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Jean François Butaud, Martin W. Callmander, and Frédéric Jacq
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0106 biological sciences ,Pandanus tectorius ,Liliopsida ,Endangered species ,Atoll ,Plant Science ,010603 evolutionary biology ,01 natural sciences ,IUCN Red List ,Pandanales ,Plantae ,Pandanaceae ,Ecology, Evolution, Behavior and Systematics ,Taxonomy ,geography ,geography.geographical_feature_category ,biology ,Ecology ,Biodiversity ,biology.organism_classification ,Tracheophyta ,Archipelago ,Threatened species ,Taxonomy (biology) ,010606 plant biology & botany - Abstract
Butaud, J.F., F. Jacq & M.W. Callmander (2019). Pandanus papateaensis (Pandanaceae): a new threatened species from the uplifted atoll Makatea (Tuamotu, French Polynesia). Candollea 74: 137–144. In French, English and French abstracts. DOI: http://dx.doi.org/10.15553/c2019v742a3The new species Pandanus papateaensis Butaud, F. Jacq & Callm. (Pandanaceae) is described from the uplifted atoll of Makatea located in the Tuamotu Archipelago of French Polynesia. The new species can be distinguished from other Polynesian species by its completely fused drupes with usually two seminal chambers and by its reddish-brown to dark-purple pileus, which totals more than one third of the total length of the drupe. Pandanus papateaensis is known from a few subpopulations located on the edge of the central plateau and it occurs in sympatry with Pandanus tectorius Parkinson. The species is known by less than 80 individuals and its sustainability is threatened by a phosphate mining project, which could have a significant impact on two of the three subpopulations. Based on the latter evidence, the new species is assigned a preliminary “Endangered” [EN] status following IUCN Red list Categories and Criteria. A regulatory protection status is thus recommended for this new species, as well as for the exceptional natural vegetation formations of this atoll, which is threatened by 50 years of intense phosphate mining without any current restoration programs to compensate for the damage caused.
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- 2019
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5. Prognostic utility of N-terminal pro B-type natriuretic peptide ratio in mixed aortic valve disease
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Erwan Salaun, Marie-Annick Clavel, Lionel Tastet, Jérémy Bernard, Guillaume Jean, David Bienjonetti-Boudreau, and Frédéric Jacques
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Objective We aimed to assess the incremental prognostic value of N-terminal-pro-B-type natriuretic peptide (Nt-proBNP) for risk stratification in mixed aortic valve disease (MAVD) patients.Methods We included 556 (73±12 years, 37% women) consecutive patients with at least a moderate aortic stenosis (AS) or aortic regurgitation (AR) lesion with a concomitant AS or AR of any severity in whom Nt-proBNP was measured and expressed as its ratio (measured Nt-proBNP divided by the upper limit of normal Nt-proBNP for age and sex). The primary endpoint was all-cause mortality.Results Baseline median Nt-proBNP ratio was 3.8 (IQR: 1.5–11.3), and the median follow-up was 5.6 years (4.8–6.1). Early aortic valve replacement (AVR) was performed within 3 months in 423 (76%) patients, while 133 (24%) remained initially under medical treatment. In comprehensive multivariable analyses, Nt-proBNP ratio was significantly associated with excess mortality (continuous variable: HR (95% CI): 1.24 (1.04 to 1.47), p=0.02; Nt-proBNP ratio ≥3: 2.41 (1.33 to 4.39), p=0.004). The independent prognostic value was also observed in patients with severe or non-severe AS/AR, and those treated by early-AVR (all p0.42, all p≤0.008). After early-AVR, Nt-proBNP ratio ≥3 was associated with higher 30-day mortality (9 (4%) vs 1 (0.5%), p=0.02).Conclusions In this series of MAVD patients, Nt-proBNP ratio was a powerful predictor of early and long-term mortality, even in patients with both non-severe AS/AR. Moreover, early-AVR may be an option for patients with Nt-proBNP ratio ≥3. Further randomised studies are needed to validate this last point.
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- 2023
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6. Real Time Predictive and Adaptive Hybrid Powertrain Control Development via Neuroevolution
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Frederic Jacquelin, Jungyun Bae, Bo Chen, Darrell Robinette, Pruthwiraj Santhosh, Troy Kraemer, and Bonnie Henderson
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minimum energy control ,optimal control ,intelligent systems ,artificial intelligence ,hybrid powertrain ,Neuroevolution ,Mechanical engineering and machinery ,TJ1-1570 ,Machine design and drawing ,TJ227-240 ,Motor vehicles. Aeronautics. Astronautics ,TL1-4050 - Abstract
The real-time application of powertrain-based predictive energy management (PrEM) brings the prospect of additional energy savings for hybrid powertrains. Torque split optimal control methodologies have been a focus in the automotive industry and academia for many years. Their real-time application in modern vehicles is, however, still lagging behind. While conventional exact and non-exact optimal control techniques such as Dynamic Programming and Model Predictive Control have been demonstrated, they suffer from the curse of dimensionality and quickly display limitations with high system complexity and highly stochastic environment operation. This paper demonstrates that Neuroevolution associated drive cycle classification algorithms can infer optimal control strategies for any system complexity and environment, hence streamlining and speeding up the control development process. Neuroevolution also circumvents the integration of low fidelity online plant models, further avoiding prohibitive embedded computing requirements and fidelity loss. This brings the prospect of optimal control to complex multi-physics system applications. The methodology presented here covers the development of the drive cycles used to train and validate the neurocontrollers and classifiers, as well as the application of the Neuroevolution process.
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- 2022
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7. Connected and Autonomous Vehicle Cohort Speed Control Optimization via Neuroevolution
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Frederic Jacquelin, Jungyun Bae, Bo Chen, Darrell Robinette, Pruthwiraj Santhosh, Joshua Orlando, and Daniel Knopp
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Minimum energy control ,optimal control ,intelligent systems ,artificial intelligence ,mobile robots ,systems engineering ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Predictive Energy Management (PrEM) research is at the forefront of modern transportation’s energy consumption reduction efforts. The development of PrEM optimization algorithms has been tailored to selfish vehicle operation and implemented in the form of vehicle dynamics and/or adaptive powertrain control functions. With the progress in vehicle automation, this paper focuses on extending PrEM into the realm of a System of Systems (SoS). The proposed approach uses the shared information among Connected and Automated Vehicles (CAV) and the infrastructure to synthesize a reduced energy speed trajectory at the cohort level within urban environments. Neuroevolution is employed to incorporate a generalized optimum controller, robust to the emergent behaviors typical of multi-agents SoS. The authors demonstrated the use of heuristics and systems engineering processes in abstracting and integrating the resulting neural network within the control architecture, which enables novel added-value features such as green wave pass/fail classification and e-Horizon velocity prediction. The resulting controller is faster than real-time and was validated with a multi-agent simulation environment and on a real-world closed-loop track at the American Center for Mobility (ACM). The GM Bolt and Volt CAV mixed cohort testing at ACM demonstrated energy reductions from 7% to 22% depending on scenarios.
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- 2022
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8. PiT2 deficiency prevents increase of bone marrow adipose tissue during skeletal maturation but not in OVX-induced osteoporosis
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Giulia Frangi, Marie Guicheteau, Frederic Jacquot, Grzegorz Pyka, Greet Kerckhofs, Magalie Feyeux, Joëlle Veziers, Pierre Guihard, Boris Halgand, Sophie Sourice, Jérôme Guicheux, Xavier Prieur, Laurent Beck, and Sarah Beck-Cormier
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PiT2/Slc20a2 ,adipocytes ,bone ,post-menopausal osteoporotic mouse model ,marrow ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
The common cellular origin between bone marrow adipocytes (BMAds) and osteoblasts contributes to the intimate link between bone marrow adipose tissue (BMAT) and skeletal health. An imbalance between the differentiation ability of BMSCs towards one of the two lineages occurs in conditions like aging or osteoporosis, where bone mass is decreased. Recently, we showed that the sodium-phosphate co-transporter PiT2/SLC20A2 is an important determinant for bone mineralization, strength and quality. Since bone mass is reduced in homozygous mutant mice, we investigated in this study whether the BMAT was also affected in PiT2-/- mice by assessing the effect of the absence of PiT2 on BMAT volume between 3 and 16 weeks, as well as in an ovariectomy-induced bone loss model. Here we show that the absence of PiT2 in juveniles leads to an increase in the BMAT that does not originate from an increased adipogenic differentiation of bone marrow stromal cells. We show that although PiT2-/- mice have higher BMAT volume than control PiT2+/+ mice at 3 weeks of age, BMAT volume do not increase from 3 to 16 weeks of age, leading to a lower BMAT volume in 16-week-old PiT2-/- compared to PiT2+/+ mice. In contrast, the absence of PiT2 does not prevent the increase in BMAT volume in a model of ovariectomy-induced bone loss. Our data identify SLC20a2/PiT2 as a novel gene essential for the maintenance of the BMAd pool in adult mice, involving mechanisms of action that remain to be elucidated, but which appear to be independent of the balance between osteoblastic and adipogenic differentiation of BMSCs.
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- 2022
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9. Dynamique d’un arbre introduit à Mayotte, Litsea glutinosa (Lauraceae) : une espèce envahissante ?
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Frédéric Jacq, Annette Hladik, and Ronald Bellefontaine
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Ecology, Evolution, Behavior and Systematics - Abstract
Dynamics of the introduced tree Litsea glutinosa (Lauraceae) in Mayotte Island : Is it an invasive species ? — Litsea glutinosa (Lour.) C. B. Rob, the Indian laurel, is a dioecious tree from Australasia which has been introduced on Mayotte and has proliferated during the era of sugar cane plantations (1841-1880). Efficiently dispersed by the Brown Lemur (Eulemur fulvus) and by numerous birds, this Lauraceae species now spreads into the humid area and it is present in the last remaining «natural» fragmented forests of the island. This tree, ranging from 10 to 15 meters in height, is mostly found on the wetter (rainfall > 1 500 mm/ year) northern part of the island. This study analyses the population dynamics of Listea glutinosa between 1996 and 2002 in the remains of the mesophilous and ombrophilous forests, as well as the importance of vegetative reproduction in certain populations. L. glutinosa proliferates in protected forests, particularly in semi-dry forests where it can take advantage of the more open forest structure. Because of its light-demanding temperament, L. glutinosa needs an opening in the forest canopy to settle down and grow. The tree’s invading nature, however, is due partially to its capability to reproduce vegetatively ; over half of the stems are produced by vegetative reproduction, mostly root-suckering. This species could lead to a specific loss of biodiversity in «natural» areas, but is not considered as a pest by local inhabitants, because of its frequent utilization, especially as fodder., Litsea glutinosa (Lour.) C. B. Rob., l’avocat marron, est un arbre dioïque d’Australasie qui a été introduit à Mayotte et multiplié à l’époque de la canne à sucre (1841-1880). Disséminée efficacement par les lémuriens (Eulemur fulvus) et par de nombreux oiseaux, cette Lauraceae s’est étendue sur toute la zone humide et est présente dans les dernières forêts «naturelles » fragmentées de l’île. Cet arbre de 10 à 15 mètres de hauteur se concentre actuellement dans les deux-tiers nord plus arrosés (pluviosité > 1 500 mm/ an) de Mayotte. Ce travail analyse la dynamique entre 1996 et 2002 des populations de Litsea glutinosa établies dans les reliquats de forêt mésophile et ombrophile et la part de la multiplication végétative dans certaines populations. L. glutinosa prolifère dans les réserves forestières et particulièrement en forêt semi-sèche en fonction de la structure forestière plus ou moins ouverte. Par son tempérament héliophile, cette espèce nécessite une perturbation pour croître et se fixer en forêt. Sa persistance et son caractère envahissant sont dus en partie à sa possibilité de multiplication végétative à l’origine de plus de la moitié des fûts, principalement par drageonnage. Cette espèce constitue un risque d’appauvrissement spécifique dans les zones «naturelles» sans pour autant être considérée par les mahorais comme une peste en raison de sa fréquente utilisation en particulier comme plante fourragère., Jacq Frédéric,Hladik Annette,Bellefontaine Ronald. Dynamique d’un arbre introduit à Mayotte, Litsea glutinosa (Lauraceae) : une espèce envahissante ?. In: Revue d'Écologie (La Terre et La Vie), tome 60, n°1, 2005. pp. 21-32.
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- 2005
10. Systemic viral spreading and defective host responses are associated with fatal Lassa fever in macaques
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Nicolas Baillet, Stéphanie Reynard, Emeline Perthame, Jimmy Hortion, Alexandra Journeaux, Mathieu Mateo, Xavier Carnec, Justine Schaeffer, Caroline Picard, Laura Barrot, Stéphane Barron, Audrey Vallve, Aurélie Duthey, Frédéric Jacquot, Cathy Boehringer, Grégory Jouvion, Natalia Pietrosemoli, Rachel Legendre, Marie-Agnès Dillies, Richard Allan, Catherine Legras-Lachuer, Caroline Carbonnelle, Hervé Raoul, and Sylvain Baize
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Biology (General) ,QH301-705.5 - Abstract
Baillet et al. use the cynomolgus monkey model to model Lassa virus and associated Lassa fever (LF). They provide a full characterisation of LF pathogenesis with the aim of assisting the development of early diagnostic tools.
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- 2021
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11. Enhanced impact-resistance of aeronautical quasi-isotropic composite plates through diffused water molecules in epoxy
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Furqan Ahmad, Fethi Abbassi, Mazhar Ul-Islam, Frédéric Jacquemin, and Jung-Wuk Hong
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Medicine ,Science - Abstract
Abstract In order to elucidate the hygroscopic effects on impact-resistance of carbon fiber/epoxy quasi-isotropic composite plates, low-velocity impact tests are conducted on dry and hygroscopically conditioned plates, respectively, under identical configurations. For the impact tests, plates were immersed in the hot water at 80 °C to absorb a different amount of moisture content (MC). Experimental results reveal that the presence of the MC plays a pivotal role by improving the impact-resistance of composite plates. Plates with higher percentage of MC could behave elastically to a larger strain, yielding larger deflection under impact loading. From SEM fractographies, it is observed that small disbanding grows at the interface of epoxy and carbon fiber due to absorbed MC. After absorbing MC, most of impact energy is dissipated in hygroscopic conditioned composite plates through elastic deformation and overall less damage is induced in wet composite plates compare to the dry plate. We can postulate that the presence of MC increases the elastic limit as well as ductility of the epoxy by promoting chain segmental mobility of the polymer molecules, which eventually leads to the enhancement of the impact-resistance of wet quasi-isotropic composite plates in comparison with the dry plate.
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- 2021
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12. Transitioning to Del Nido cardioplegia for all-comers: the next switching gear?
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Mohamed Marzouk, Valerie Lafreniere-Bessi, Stephanie Dionne, Serge Simard, Christian Pigeon, François Dagenais, Niv Ad, and Frederic Jacques
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Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background Exclusive use of Del Nido cardioplegia administration in all adult patients undergoing cardiac surgery has been studied for operative, postoperative and myocardial protection outcomes. Methods From November 2016 to October 2017, Del Nido cardioplegia was used in 131 consecutive patients (DN group). Using a propensity score, DN group was compared to 251 patients having received intermittent cold blood cardioplegia (CB group). Results Preoperative characteristics were similar in DN and CB groups. Operative outcomes were statistically different (p
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- 2020
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13. Investigation of the antioxidant capacity of caramels: Combination of laboratory assays and C. elegans model
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Cédric Moretton, Cécile Gouttefangeas, Constance Dubois, Frédéric Jacques Tessier, Chantal Fradin, Emmanuelle Prost-Camus, Michel Prost, Marc Haumont, and Henri Nigay
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Caramel ,Antioxidant ,TEAC ,KRL ,C. elegans ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Caramel is one of the most current additive/ingredient obtained by controlled heat treatment of carbohydrates.A combination of in vitro and in vivo methods showed that aromatic caramels and caramel colours are antioxidant. The highest value is obtained for Class III caramel colours for in vitro TEAC and KRL tests (401 µmol Trolox equivalent/g and 5 366 mg gallic acid equivalent/100 g, respectively). In in vivo test, caramels also increase the resistance of C. elegans to oxidant attack, with until 40% live worms after 18 h of treatment in the presence of caramels against no live worms after 12 h of treatment without.In conclusion, this study explore benefit effect of caramels and showed an antioxidant activity linked to their color intensity. The molecules involved remain to be explored.
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- 2021
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14. Ebola viral dynamics in nonhuman primates provides insights into virus immuno-pathogenesis and antiviral strategies
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Vincent Madelain, Sylvain Baize, Frédéric Jacquot, Stéphanie Reynard, Alexandra Fizet, Stephane Barron, Caroline Solas, Bruno Lacarelle, Caroline Carbonnelle, France Mentré, Hervé Raoul, Xavier de Lamballerie, and Jérémie Guedj
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Science - Abstract
Optimization of antiviral therapy can be crucial in the management of Ebola virus outbreaks. Here, Madelain et al. use an integrative mathematical model to correlate the dose and the time of treatment initiation with survival rate, enhanced immune response and viral clearance.
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- 2018
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15. Post-exposure treatment of non-human primates lethally infected with Ebola virus with EBOTAb, a purified ovine IgG product
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Stuart D. Dowall, Frédéric Jacquot, John Landon, Emma Rayner, Graham Hall, Caroline Carbonnelle, Hervé Raoul, Delphine Pannetier, Ian Cameron, Ruth Coxon, Ibrahim Al Abdulla, Roger Hewson, and Miles W. Carroll
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Medicine ,Science - Abstract
Abstract Despite sporadic outbreaks of Ebola virus (EBOV) over the last 4 decades and the recent public health emergency in West Africa, there are still no approved vaccines or therapeutics for the treatment of acute EBOV disease (EVD). In response to the 2014 outbreak, an ovine immunoglobulin therapy was developed, termed EBOTAb. After promising results in the guinea pig model of EBOV infection, EBOTAb was tested in the cynomolgus macaque non-human primate model of lethal EBOV infection. To ensure stringent therapeutic testing conditions to replicate likely clinical usage, EBOTAb was first delivered 1, 2 or 3 days post-challenge with a lethal dose of EBOV. Results showed a protective effect of EBOTAb given post-exposurally, with survival rates decreasing with increasing time after challenge. Viremia results demonstrated that EBOTAb resulted in a decreased circulation of EBOV in the bloodstream. Additionally, assay of liver enzymes and histology analysis of local tissues identified differences between EBOTAb-treated and untreated groups. The results presented demonstrate that EBOTAb conferred protection against EBOV when given post-exposure and should be explored and developed further as a potential intervention strategy for future outbreaks, which are likely to occur.
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- 2017
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16. Post esophagectomy diaphragmatic hernia: a case report of a rare cause of acute respiratory distress
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Valérie Lamontagne, Valérie Lafrenière-Bessi, Arthur Vieira, Éric Charbonneau, Paula A. Ugalde, and Frédéric Jacques
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Diaphragmatic hernia ,Respiratory distress ,Post-esophagectomy ,Cardiac surgery ,Surgery ,RD1-811 ,Anesthesiology ,RD78.3-87.3 - Abstract
Abstract Background Diaphragmatic hernia is frequent among the elderly and is usually associated with mild chronic digestive and respiratory symptoms. Case presentation An elderly post-esophagectomy male patient, in the early postoperative period of cardiac surgery, presented with acute respiratory distress. An emergent surgery was performed to reduce a giant diaphragmatic herniation. Conclusions An acute transhiatal herniation can cause serious respiratory impairment; surgical repair should be considered in select patients of cardiac surgery.
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- 2018
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17. Early diaphragmatic plication after cardiac surgery: a case report in an obese patient
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Valérie Lafrenière-Bessi, Frédéric Jacques, Richard Baillot, Jean Bussières, Paola A. Ugalde, and Stephan Langevin
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Diaphragmatic plication ,Ventilation weaning ,Cardiothoracic surgery ,Surgery ,RD1-811 ,Anesthesiology ,RD78.3-87.3 - Abstract
Abstract Background Diaphragmatic plication to help ventilation weaning of an adult obese patient after cardiac surgery is very uncommon. Diaphragm paralysis is usually treated with conservative measures and ventilator support, after which surgical management is considered after months of medical monitoring. Case presentation We report the case of a morbidly obese patient to whom ventilation weaning was unsuccessful following coronary artery bypass graft operation with mitral valve replacement. A de novo right hemidiaphragm elevation was seen on the chest X-ray. Diaphragmatic plication was performed promptly to treat severe respiratory insufficiency and generated favorable outcomes. Conclusions Early diaphragmatic plication could be considered in the postoperative period of cardiothoracic surgery to facilitate management and ventilation weaning in the context of de novo diaphragm paralysis.
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- 2018
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18. Wolff-Parkinson-White as a bystander in a patient with aborted sudden cardiac death
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Jamal Laaouaj, MD, Frédéric Jacques, MD, Gilles O’Hara, MD, Jean Champagne, MD, Jean-François Sarrazin, MD, FHRS, Isabelle Nault, MD, and François Philippon, MD, FHRS
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Sudden cardiac death ,WPW syndrome ,Anomalous origin of coronary arteries ,Clinical electrophysiology ,Investigation of sudden cardiac death ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Published
- 2016
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19. Antiviral efficacy of favipiravir against Ebola virus: A translational study in cynomolgus macaques.
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Jérémie Guedj, Géraldine Piorkowski, Frédéric Jacquot, Vincent Madelain, Thi Huyen Tram Nguyen, Anne Rodallec, Stephan Gunther, Caroline Carbonnelle, France Mentré, Hervé Raoul, and Xavier de Lamballerie
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Medicine - Abstract
BackgroundDespite repeated outbreaks, in particular the devastating 2014-2016 epidemic, there is no effective treatment validated for patients with Ebola virus disease (EVD). Among the drug candidates is the broad-spectrum polymerase inhibitor favipiravir, which showed a good tolerance profile in patients with EVD (JIKI trial) but did not demonstrate a strong antiviral efficacy. In order to gain new insights into the antiviral efficacy of favipiravir and improve preparedness and public health management of future outbreaks, we assess the efficacy achieved by ascending doses of favipiravir in Ebola-virus-infected nonhuman primates (NHPs).Methods and findingsA total of 26 animals (Macaca fascicularis) were challenged intramuscularly at day 0 with 1,000 focus-forming units of Ebola virus Gabon 2001 strain and followed for 21 days (study termination). This included 13 animals left untreated and 13 treated with doses of 100, 150, and 180 mg/kg (N = 3, 5, and 5, respectively) favipiravir administered intravenously twice a day for 14 days, starting 2 days before infection. All animals left untreated or treated with 100 mg/kg died within 10 days post-infection, while animals receiving 150 and 180 mg/kg had extended survival (P < 0.001 and 0.001, respectively, compared to untreated animals), leading to a survival rate of 40% (2/5) and 60% (3/5), respectively, at day 21. Favipiravir inhibited viral replication (molecular and infectious viral loads) in a drug-concentration-dependent manner (P values < 0.001), and genomic deep sequencing analyses showed an increase in virus mutagenesis over time. These results allowed us to identify that plasma trough favipiravir concentrations greater than 70-80 μg/ml were associated with reduced viral loads, lower virus infectivity, and extended survival. These levels are higher than those found in the JIKI trial, where patients had median trough drug concentrations equal to 46 and 26 μg/ml at day 2 and day 4 post-treatment, respectively, and suggest that the dosing regimen in the JIKI trial was suboptimal. The environment of a biosafety level 4 laboratory introduces a number of limitations, in particular the difficulty of conducting blind studies and performing detailed pharmacological assessments. Further, the extrapolation of the results to patients with EVD is limited by the fact that the model is fully lethal and that treatment initiation in patients with EVD is most often initiated several days after infection, when symptoms and high levels of viral replication are already present.ConclusionsOur results suggest that favipiravir may be an effective antiviral drug against Ebola virus that relies on RNA chain termination and possibly error catastrophe. These results, together with previous data collected on tolerance and pharmacokinetics in both NHPs and humans, support a potential role for high doses of favipiravir for future human interventions.
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- 2018
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20. Naître du monde et naître au monde. Merleau-Ponty / Patočka
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Frédéric Jacquet
- Subjects
Merleau-Ponty ,Patočka ,phenomenology ,ontology ,birth ,Philosophy (General) ,B1-5802 - Abstract
The phenomenon of birth is here to be presented as a crucial one, discreet though, into Merleau-Ponty and Patočka’s philosophy. So it deserves a confrontation of their respective thoughts. Both of them have radicalised Husserl’s phenomenology into a philosophy of birth. This phenomenological achievement includes an ontology of birth, which feeds an anthropology in a brand new way, presented in the following pages.
- Published
- 2013
21. Favipiravir pharmacokinetics in Ebola-Infected patients of the JIKI trial reveals concentrations lower than targeted.
- Author
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Thi Huyen Tram Nguyen, Jérémie Guedj, Xavier Anglaret, Cédric Laouénan, Vincent Madelain, Anne-Marie Taburet, Sylvain Baize, Daouda Sissoko, Boris Pastorino, Anne Rodallec, Géraldine Piorkowski, Sara Carazo, Mamoudou N Conde, Jean-Luc Gala, Joseph Akoi Bore, Caroline Carbonnelle, Frédéric Jacquot, Hervé Raoul, Denis Malvy, Xavier de Lamballerie, France Mentré, and JIKI study group
- Subjects
Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BACKGROUND:In 2014-2015, we assessed favipiravir tolerance and efficacy in patients with Ebola virus (EBOV) disease (EVD) in Guinea (JIKI trial). Because the drug had never been used before for this indication and that high concentrations of the drugs were needed to achieve antiviral efficacy against EBOV, a pharmacokinetic model had been used to propose relevant dosing regimen. Here we report the favipiravir plasma concentrations that were achieved in participants in the JIKI trial and put them in perspective with the model-based targeted concentrations. METHODS AND FINDINGS:Pre-dose drug concentrations were collected at Day-2 and Day-4 of treatment in 66 patients of the JIKI trial and compared to those predicted by the model taking into account patient's individual characteristics. At Day-2, the observed concentrations were slightly lower than the model predictions adjusted for patient's characteristics (median value of 46.1 versus 54.3 μg/mL for observed and predicted concentrations, respectively, p = 0.012). However, the concentrations dropped at Day-4, which was not anticipated by the model (median values of 25.9 and 64.4 μg/mL for observed and predicted concentrations, respectively, p
- Published
- 2017
- Full Text
- View/download PDF
22. The NS Segment of H1N1pdm09 Enhances H5N1 Pathogenicity in a Mouse Model of Influenza Virus Infections
- Author
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Olivier Ferraris, Jean-Sébastien Casalegno, Emilie Frobert, Maude Bouscambert Duchamp, Martine Valette, Frédéric Jacquot, Hervé Raoul, Bruno Lina, and Michèle Ottmann
- Subjects
virus ,influenza ,influenza A ,H5N1 ,H1N1pdm ,reassortment ,pathogenicity ,mouse model ,Microbiology ,QR1-502 - Abstract
In 2009, the co-circulation of H5N1 and H1N1pdm09 raised concerns that a reassortment event may lead to highly pathogenic influenza strains. H1N1pdm09 and H5N1 are able to infect the same target cells of the lower respiratory tract. To investigate the capacity of the emergence of reassortant viruses, we characterized viruses obtained from the co-infection of cells with H5N1 (A/Turkey/13/2006) and H1N1pdm09 (A/Lyon/969/2009 H1N1). In our analysis, all the screened reassortants possessed the PB2, HA, and NP segments from H5N1 and acquired one or two of the H1N1pdm09 segments. Moreover, the in vivo infections showed that the acquisition of the NS segment from H1N1pdm09 increased the virulence of H5N1 in mice. We conclude, therefore, that reassortment can occur between these two viruses, even if this process has never been detected in nature.
- Published
- 2018
- Full Text
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23. Anti-EBOV GP IgGs Lacking α1-3-Galactose and Neu5Gc Prolong Survival and Decrease Blood Viral Load in EBOV-Infected Guinea Pigs.
- Author
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Olivier Reynard, Frédéric Jacquot, Gwénaëlle Evanno, Hoa Le Mai, Apolline Salama, Bernard Martinet, Odile Duvaux, Jean-Marie Bach, Sophie Conchon, Jean-Paul Judor, Andrea Perota, Irina Lagutina, Roberto Duchi, Giovanna Lazzari, Ludmilla Le Berre, Hélène Perreault, Elsa Lheriteau, Hervé Raoul, Viktor Volchkov, Cesare Galli, and Jean-Paul Soulillou
- Subjects
Medicine ,Science - Abstract
Polyclonal xenogenic IgGs, although having been used in the prevention and cure of severe infectious diseases, are highly immunogenic, which may restrict their usage in new applications such as Ebola hemorrhagic fever. IgG glycans display powerful xenogeneic antigens in humans, for example α1-3 Galactose and the glycolyl form of neuraminic acid Neu5Gc, and IgGs deprived of these key sugar epitopes may represent an advantage for passive immunotherapy. In this paper, we explored whether low immunogenicity IgGs had a protective effect on a guinea pig model of Ebola virus (EBOV) infection. For this purpose, a double knock-out pig lacking α1-3 Galactose and Neu5Gc was immunized against virus-like particles displaying surface EBOV glycoprotein GP. Following purification from serum, hyper-immune polyclonal IgGs were obtained, exhibiting an anti-EBOV GP titer of 1:100,000 and a virus neutralizing titer of 1:100. Guinea pigs were injected intramuscularly with purified IgGs on day 0 and day 3 post-EBOV infection. Compared to control animals treated with IgGs from non-immunized double KO pigs, the anti-EBOV IgGs-treated animals exhibited a significantly prolonged survival and a decreased virus load in blood on day 3. The data obtained indicated that IgGs lacking α1-3 Galactose and Neu5Gc, two highly immunogenic epitopes in humans, have a protective effect upon EBOV infection.
- Published
- 2016
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24. Study of the role of cytosolic phospholipase A2 alpha in eicosanoid generation and thymocyte maturation in the thymus.
- Author
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Matthieu Rousseau, Gajendra S Naika, Jean Perron, Frederic Jacques, Michael H Gelb, and Eric Boilard
- Subjects
Medicine ,Science - Abstract
The thymus is a primary lymphoid organ, home of maturation and selection of thymocytes for generation of functional T-cells. Multiple factors are involved throughout the different stages of the maturation process to tightly regulate T-cell production. The metabolism of arachidonic acid by cyclooxygenases, lipoxygenases and specific isomerases generates eicosanoids, lipid mediators capable of triggering cellular responses. In this study, we determined the profile of expression of the eicosanoids present in the mouse thymus at different stages of thymocyte development. As the group IVA cytosolic phospholipase A2 (cPLA2α) catalyzes the hydrolysis of phospholipids, thereby generating arachidonic acid, we further verified its contribution by including cPLA2α deficient mice to our investigations. We found that a vast array of eicosanoids is expressed in the thymus, which expression is substantially modulated through thymocyte development. The cPLA2α was dispensable in the generation of most eicosanoids in the thymus and consistently, the ablation of the cPLA2α gene in mouse thymus and the culture of thymuses from human newborns in presence of the cPLA2α inhibitor pyrrophenone did not impact thymocyte maturation. This study provides information on the eicosanoid repertoire present during thymocyte development and suggests that thymocyte maturation can occur independently of cPLA2α.
- Published
- 2015
- Full Text
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25. Detection and quantification of microparticles from different cellular lineages using flow cytometry. Evaluation of the impact of secreted phospholipase A2 on microparticle assessment.
- Author
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Matthieu Rousseau, Clemence Belleannee, Anne-Claire Duchez, Nathalie Cloutier, Tania Levesque, Frederic Jacques, Jean Perron, Peter A Nigrovic, Melanie Dieude, Marie-Josee Hebert, Michael H Gelb, and Eric Boilard
- Subjects
Medicine ,Science - Abstract
Microparticles, also called microvesicles, are submicron extracellular vesicles produced by plasma membrane budding and shedding recognized as key actors in numerous physio(patho)logical processes. Since they can be released by virtually any cell lineages and are retrieved in biological fluids, microparticles appear as potent biomarkers. However, the small dimensions of microparticles and soluble factors present in body fluids can considerably impede their quantification. Here, flow cytometry with improved methodology for microparticle resolution was used to detect microparticles of human and mouse species generated from platelets, red blood cells, endothelial cells, apoptotic thymocytes and cells from the male reproductive tract. A family of soluble proteins, the secreted phospholipases A2 (sPLA2), comprises enzymes concomitantly expressed with microparticles in biological fluids and that catalyze the hydrolysis of membrane phospholipids. As sPLA2 can hydrolyze phosphatidylserine, a phospholipid frequently used to assess microparticles, and might even clear microparticles, we further considered the impact of relevant sPLA2 enzymes, sPLA2 group IIA, V and X, on microparticle quantification. We observed that if enriched in fluids, certain sPLA2 enzymes impair the quantification of microparticles depending on the species studied, the source of microparticles and the means of detection employed (surface phosphatidylserine or protein antigen detection). This study provides analytical considerations for appropriate interpretation of microparticle cytofluorometric measurements in biological samples containing sPLA2 enzymes.
- Published
- 2015
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26. Recombinant measles virus vaccine expressing the Nipah virus glycoprotein protects against lethal Nipah virus challenge.
- Author
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Misako Yoneda, Marie-Claude Georges-Courbot, Fusako Ikeda, Miho Ishii, Noriyo Nagata, Frederic Jacquot, Hervé Raoul, Hiroki Sato, and Chieko Kai
- Subjects
Medicine ,Science - Abstract
Nipah virus (NiV) is a member of the genus Henipavirus, which emerged in Malaysia in 1998. In pigs, infection resulted in a predominantly non-lethal respiratory disease; however, infection in humans resulted in over 100 deaths. Nipah virus has continued to re-emerge in Bangladesh and India, and person-to-person transmission appeared in the outbreak. Although a number of NiV vaccine studies have been reported, there are currently no vaccines or treatments licensed for human use. In this study, we have developed a recombinant measles virus (rMV) vaccine expressing NiV envelope glycoproteins (rMV-HL-G and rMV-Ed-G). Vaccinated hamsters were completely protected against NiV challenge, while the mortality of unvaccinated control hamsters was 90%. We trialed our vaccine in a non-human primate model, African green monkeys. Upon intraperitoneal infection with NiV, monkeys showed several clinical signs of disease including severe depression, reduced ability to move and decreased food ingestion and died at 7 days post infection (dpi). Intranasal and oral inoculation induced similar clinical illness in monkeys, evident around 9 dpi, and resulted in a moribund stage around 14 dpi. Two monkeys immunized subcutaneously with rMV-Ed-G showed no clinical illness prior to euthanasia after challenge with NiV. Viral RNA was not detected in any organ samples collected from vaccinated monkeys, and no pathological changes were found upon histopathological examination. From our findings, we propose that rMV-NiV-G is an appropriate NiV vaccine candidate for use in humans.
- Published
- 2013
- Full Text
- View/download PDF
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