Le Studium Loire Valley Institute for Advanced Studies

Saint-Mathurin-sur-Loire, France

Le Studium Loire Valley Institute for Advanced Studies

Saint-Mathurin-sur-Loire, France
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Boulay R.,Le Studium Loire Valley Institute for Advanced Studies | Boulay R.,University of Tours | Aron S.,Le Studium Loire Valley Institute for Advanced Studies | Aron S.,Free University of Colombia | And 10 more authors.
Annual Review of Entomology | Year: 2017

Unlike most desert-dwelling animals, Cataglyphis ants do not attempt to escape the heat; rather, they apply their impressive heat tolerance to avoid competitors and predators. This thermally defined niche has promoted a range of adaptations both at the individual and colony levels. We have also recently discovered that within the genus Cataglyphis there are incredibly diverse social systems, modes of reproduction, and dispersal, prompting the tantalizing question of whether social diversity may also be a consequence of the harsh environment within which we find these charismatic ants. Here we review recent advances regarding the physiological, behavioral, life-history, colony, and ecological characteristics of Cataglyphis and consider perspectives on future research that will build our understanding of organic adaptive responses to desertification. © 2017 by Annual Reviews. All rights reserved.


Gomes I.,Mount Sinai School of Medicine | Ayoub M.A.,CNRS Physiology of Reproduction and Behaviors | Ayoub M.A.,LE STUDIUM Loire Valley Institute for Advanced Studies | Fujita W.,Mount Sinai School of Medicine | And 7 more authors.
Annual Review of Pharmacology and Toxicology | Year: 2016

G protein-coupled receptors (GPCRs) compose one of the largest families of membrane proteins involved in intracellular signaling. They are involved in numerous physiological and pathological processes and are prime candidates for drug development. Over the past decade, an increasing number of studies have reported heteromerization between GPCRs. Many investigations in heterologous systems have provided important indications of potential novel pharmacology; however, the physiological relevance of these findings has yet to be established with endogenous receptors in native tissues. In this review, we focus on family A GPCRs and describe the techniques and criteria to assess their heteromerization. We conclude that advances in approaches to study receptor complex functionality in heterologous systems, coupled with techniques that enable specific examination of native receptor heteromers in vivo, are likely to establish GPCR heteromers as novel therapeutic targets. Copyright © 2016 by Annual Reviews. All rights reserved.


Berchel M.,French National Center for Scientific Research | Akhter S.,CNRS Center for Molecular Biophysics | Akhter S.,Le Studium Loire Valley Institute for Advanced Studies | Berthe W.,French National Center for Scientific Research | And 5 more authors.
Journal of Materials Chemistry B | Year: 2017

Cationic lipid/co-lipid combinations have been extensively explored in gene delivery as alternatives to viral vectors. To be established as a gold standard of chemical vectors, considerable improvement in their transfection efficiency is however required. Herein, we report a simple procedure to synthesize new cationic lipids and co-lipids for the DNA transfection of dendritic cells (DCs). Seven α-amino-lipophosphonates featuring two aza-heterocycles with protonable sites (imidazole or pyridine) were synthesized and used as co-lipids in liposomes with cationic lipids. For each liposome, the cationic lipid is either an imidazolium lipophosphoramidate (lipid 2) or an α-amino-lipophosphonate containing a basic tertiary aliphatic amine in the polar head group (lipid 3b). The cationic lipids either with new co-lipids or DOPE formed positively charged nano-sized stable liposomes that effectively interact with plasmid DNA (pDNA) to produce lipoplexes. Membrane fusion studies showed that α-amino-phosphonates featuring an imidazole moiety in the polar head group exhibited higher fusion at pH 5.5 than pH 7.4. This study suggests that the best formulations for the transfection of DCs (based on the % transfected cells and the intensity of EGFP-based fluorescence) are lipid 2 associated with either 3a, 3d or DOPE and cationic lipid 3b formulated with 3a or DOPE as a helper lipid. Furthermore, lipid 3a could be used as an alternative to DOPE as a helper lipid. Overall, these results indicate that novel imidazole containing α-amino-phosphonates can serve as effective transfection agents for DC-based vaccines. © 2017 The Royal Society of Chemistry.


Trivedi E.R.,University of Michigan | Eliseeva S.V.,CNRS Center for Molecular Biophysics | Eliseeva S.V.,Le STUDIUM Loire Valley Institute for Advanced Studies | Jankolovits J.,University of Michigan | And 3 more authors.
Journal of the American Chemical Society | Year: 2014

Near-infrared (NIR) luminescent lanthanide complexes hold great promise for practical applications, as their optical properties have several complementary advantages over organic fluorophores and semiconductor nanoparticles. The fundamental challenge for lanthanide luminescence is their sensitization through suitable chromophores. The use of the metallacrown (MC) motif is an innovative strategy to arrange several organic sensitizers at a well-controlled distance from a lanthanide cation. Herein we report a series of lanthanide "encapsulated sandwich" MC complexes of the form Ln 3+[12-MCZn(II),quinHA-4]2[24-MC Zn(II),quinHA-8] (Ln3+[Zn(II)MCquinHA]) in which the MC framework is formed by the self-assembly of Zn2+ ions and tetradentate chromophoric ligands based on quinaldichydroxamic acid (quinHA). A first-generation of luminescent MCs was presented previously but was limited due to excitation wavelengths in the UV. We report here that through the design of the chromophore of the MC assembly, we have significantly shifted the absorption wavelength toward lower energy (450 nm). In addition to this near-visible inter- and/or intraligand charge transfer absorption, Ln 3+[Zn(II)MCquinHA] exhibits remarkably high quantum yields, long luminescence lifetimes (CD3OD; Yb3+, QLnL = 2.88(2)%, τobs = 150.7(2) μs; Nd3+, QLnL = 1.35(1)%, τobs = 4.11(3) μs; Er3+, QLnL = 3.60(6)·10-2%, τobs = 11.40(3) μs), and excellent photostability. Quantum yields of Nd3+ and Er3+ MCs in the solid state and in deuterated solvents, upon excitation at low energy, are the highest values among NIR-emitting lanthanide complexes containing C-H bonds. The versatility of the MC strategy allows modifications in the excitation wavelength and absorptivity through the appropriate design of the ligand sensitizer, providing a highly efficient platform with tunable properties. © 2014 American Chemical Society.


Rahman M.,Jamia Hamdard University | Rahman M.,Sam Higginbottom Institute of Agriculture, Technology and Sciences | Akhter S.,LE STUDIUM Loire Valley Institute for Advanced Studies | Akhter S.,CNRS Center for Molecular Biophysics | And 5 more authors.
Nanomedicine | Year: 2015

As an inorganic nanomaterial, graphene nanocomposites have gained much attention in cancer nanotechnology compared with the other inorganic nanomaterial in recent times. Although a relatively new drug carrier, it has been extensively explored as a potential chemotherapeutic carrier and theranostic because of its numerous physicochemical properties, including, capability of multiple pay load, functionalization for drug targeting and photothermal effect. Despite potential benefit, its translation from bench to bed-side in cancer therapy is challenged due to its toxicity concern. Here, we discussed the present progress and future possibilities of graphene nanocomposites as a cancer theranostic. Moreover, the paper also exemplifies the effects of graphene/graphene oxide on tissues and organ functions in order to understand the extent and mechanism of toxicity. © 2015 Future Medicine Ltd.


Goles E.,Adolfo Ibáñez University | Goles E.,Le Studium Loire Valley Institute for Advanced Studies | Montealegre P.,INSA Val de Loire
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2016

Consider the robust prediction problem for some automaton as the one consisting in determine, given an initial configuration, if there exists a nonzero probability that some selected site change states, when the network is updated picking one site at a time uniformly at random. We show that the robust prediction is in NC for the two-dimensional, von Neumann neighborhood, strict majority automaton. © Springer International Publishing Switzerland 2016.


PubMed | CNRS Systematics, Biodiversity and Evolution Institute, Paris-Sorbonne University, Institut Universitaire de France, Tel Aviv University and 3 more.
Type: | Journal: Annual review of entomology | Year: 2016

Unlike most desert-dwelling animals, Cataglyphis ants do not attempt to escape the heat; rather, they apply their impressive heat tolerance to avoid competitors and predators. This thermally defined niche has promoted a range of adaptations both at the individual and colony levels. We have also recently discovered that within the genus Cataglyphis there are incredibly diverse social systems, modes of reproduction, and dispersal, prompting the tantalizing question of whether social diversity may also be a consequence of the harsh environment within which we find these charismatic ants. Here we review recent advances regarding the physiological, behavioral, life-history, colony, and ecological characteristics of Cataglyphis and consider perspectives on future research that will build our understanding of organic adaptive responses to desertification. Expected final online publication date for the Annual Review of Entomology Volume 62 is January 07, 2017. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.


Goles E.,Adolfo Ibáñez University | Goles E.,Le Studium Loire Valley Institute for Advanced Studies | Montealegre P.,CNRS Orleans Fundamental Informatics Laboratory | Vera J.,Adolfo Ibáñez University
Journal of Cellular Automata | Year: 2016

In this paper we introduce automata networks to model some features of the emergence of a vocabulary related with the naming game model.We study the dynamical behaviour (attractors and convergence) of extremal and majority local functions. © 2016 Old City Publishing, Inc.


Guiguet A.,CNRS Research Institute of Insect Biology | Guiguet A.,Ecole Normale Superieure de Lyon | Dubreuil G.,CNRS Research Institute of Insect Biology | Harris M.O.,North Dakota State University | And 6 more authors.
Journal of Insect Physiology | Year: 2016

Insects that reprogram host plants during colonization remind us that the insect side of plant-insect story is just as interesting as the plant side. Insect effectors secreted by the salivary glands play an important role in plant reprogramming. Recent discoveries point to large numbers of salivary effectors being produced by a single herbivore species. Since genetic and functional characterization of effectors is an arduous task, narrowing the field of candidates is useful. We present ideas about types and functions of effectors from research on blood-feeding parasites and their mammalian hosts. Because of their importance for human health, blood-feeding parasites have more tools from genomics and other - omics than plant-feeding parasites. Four themes have emerged: (1) mechanical damage resulting from attack by blood-feeding parasites triggers "early danger signals" in mammalian hosts, which are mediated by eATP, calcium, and hydrogen peroxide, (2) mammalian hosts need to modulate their immune responses to the three "early danger signals" and use apyrases, calreticulins, and peroxiredoxins, respectively, to achieve this, (3) blood-feeding parasites, like their mammalian hosts, rely on some of the same "early danger signals" and modulate their immune responses using the same proteins, and (4) blood-feeding parasites deploy apyrases, calreticulins, and peroxiredoxins in their saliva to manipulate the "danger signals" of their mammalian hosts. We review emerging evidence that plant-feeding insects also interfere with "early danger signals" of their hosts by deploying apyrases, calreticulins and peroxiredoxins in saliva. Given emerging links between these molecules, and plant growth and defense, we propose that these effectors interfere with phytohormone signaling, and therefore have a special importance for gall-inducing and leaf-mining insects, which manipulate host-plants to create better food and shelter. © 2015 Elsevier Ltd.


Goncalves C.,CNRS Center for Molecular Biophysics | Goncalves C.,University of Orléans | Akhter S.,CNRS Center for Molecular Biophysics | Akhter S.,University of Orléans | And 5 more authors.
Molecular Pharmaceutics | Year: 2016

Intracellular availability of nucleic acids from synthetic vectors is critical and directly influences the transfection efficiency (TE). Herein, we evaluated the TE of polymer- and lipid-based nanoplexes (polyplexes, lipoplexes and lipopolyplexes) of EGFP-encoding mRNA and pDNA. To determine the translation and transcription efficiency of each nucleic acid nanoplex, in vitro expression was measured in HEK293T7 cells that permit gene expression in the cytoplasmic region. Globally, mRNA transfection profile was well corroborative with cytoplasmic transfection of pT7-pDNA as well as with nuclear transfection of pCMV-DNA. Irrespective of the nucleic acid, high TE was observed with histidinylated l-polyethylenimine (His-lPEI) polyplexes and dioleyl succinyl paromomycin/O,O-dioleyl-N-histamine phosphoramidate (DOPS/MM27) lipoplexes. Moreover, His-lPEI polyplexes yielded higher in vitro expression of EGFP for pDNA than for mRNA. Furthermore, a significant enhancement in the TE in the presence of an excess of His-lPEI was observed indicating that this polymer promotes cytosolic delivery. Compared to other nanoplexes, His-lPEI polyplex showed high intracellular availability of DNA and mRNA along with low cytotoxicity, owing to its rapid (complete or partial) unpacking in the cytosol and/or endosomes. This study gives an insight that, whether with mRNA or pDNA, enhancing nanoplex unpacking in the endosomes and cytosol would improve the delivery of nucleic acid in the cytosol and particularly in the case of pDNA where a sufficient available amount of pDNA in the cytoplasm would definitely improve its transport toward the nucleus. © 2016 American Chemical Society.

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