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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.


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.


Abdulrahman A.O.,King Saud University | Ismael M.A.,King Saud University | Al-Hosaini K.,King Saud University | Rame C.,French National Center for Scientific Research | And 12 more authors.
Frontiers in Endocrinology | Year: 2016

Previous studies on the Arabian camel (Camelus dromedarius) showed beneficial effects of its milk reported in diverse models of human diseases, including a substantial hypoglycemic activity. However, the cellular and molecular mechanisms involved in such effects remain completely unknown. In this study, we hypothesized that camel milk may act at the level of human insulin receptor (hIR) and its related intracellular signaling pathways. Therefore, we examined the effect of camel milk on the activation of hIR transiently expressed in human embryonic kidney 293 (HEK293) cells using bioluminescence resonance energy transfer (BRET) technology. BRET was used to assess, in live cells and real-time, the physical interaction between hIR and insulin receptor signaling proteins (IRS1) and the growth factor receptor-bound protein 2 (Grb2). Our data showed that camel milk did not promote any increase in the BRET signal between hIR and IRS1 or Grb2 in the absence of insulin stimulation. However, it significantly potentiated the maximal insulin-promoted BRET signal between hIR and Grb2 but not IRS1. Interestingly, camel milk appears to differentially impact the downstream signaling since it significantly activated ERK1/2 and potentiated the insulin-induced ERK1/2 but not Akt activation. These observations are to some extent consistent with the BRET data since ERK1/2 and Akt activation are known to reflect the engagement of Grb2 and IRS1 pathways, respectively. The preliminary fractionation of camel milk suggests the peptide/protein nature of the active component in camel milk. Together, our study demonstrates for the first time an allosteric effect of camel milk on insulin receptor conformation and activation with differential effects on its intracellular signaling. These findings should help to shed more light on the hypoglycemic activity of camel milk with potential therapeutic applications. © 2016 Abdulrahman, Ismael, Al-Hosaini, Rame, Al-Senaidy, Dupont and Ayoub.


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.


Ahmad M.Z.,Najran University | Abdel-Wahab B.A.,Assiut University | Abdel-Wahab B.A.,Najran University | Alam A.,Himachal Pradesh University | And 7 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2016

Nano-sized inorganic materials as inorganic nanoparticles (iNPs) are widely used for diagnostics, drug delivery and theranostics purposes at preclinical and clinical for various biomedical applications intended for human health care. Per se, iNPs offer distinctive features compared to their organic counterparts while developing imaging agents, nano-drug carriers and theranostics in many aspects. Yet, transition from laboratory to clinic for iNPs restricted or slow by the concern of toxicities around them in vivo and in vitro applications. Researchers have shown that iNPs are potentially useful from a biomedical perspective but can also give rise to unexpected and hazardous toxicities to human health in short and/or in long term exposure. iNPs can potentially cause hostile effect on cells, genetic materials, tissues, organs and proteins due to their compositions, high energy state and other unique physiochemical properties at nano-scale. The Pharmacokinetic/pharmacodynamics and interaction of iNPs with biological system are largely dependent on the physicochemical properties of iNPs, for instance size, shape, electric charge, chemical composition, surface structure, solubility and aggregation behaviour. Herein we discussed in detail about the toxicity issues (in-vitro and in-vivo) associated with the exposure of iNPs in biomedical applications. Copyright © 2016 American Scientific Publishers.


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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