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118 results on '"Caroline Martel"'

1. Experimental Evidence of Primary Permeability at Very Low Gas Content in Crystal‐Rich Silicic Magma

Author: Anna Theurel, Marielle Collombet, Alain Burgisser, Caroline Martel, Laurent Arbaret, and Rémi Champallier
Subjects: experimental volcanology, bubble coalescence, gas permeability, magmatic outgassing, percolation, Geophysics. Cosmic physics, QC801-809
Abstract: Abstract Eruptive dynamics is influenced by gas escape from the ascending magma. Gas pathways form in the magma via bubble coalescence, leading to gas channeling. Magmatic crystals play a key role in gas channel formation. This work constrains experimentally decompression‐induced coalescence in high‐crystallinity silicic magmas without external deformation, focusing on low gas content and bimodal crystal size (microlites and phenocrysts). All percolating samples have permeabilities of 10−14 m2 at bulk porosities of 7–10 vol% and bulk crystallinities up to 75 vol%. Our results demonstrate the possibility of coalescence‐related outgassing at high pressure (120–350 MPa) and without external strain, which corresponds to magma stagnating deep in a volcanic conduit. Channeling at such low gas content implies that bimodal crystallinity favors effusive over explosive volcanic behavior. It may also be the missing physical mechanism explaining gas transfer across magmatic systems despite high melt viscosity and low or absent magma extrusion.
Published: 2024
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2. A novel peanut allergy immunotherapy: Plant-based enveloped Ara h 2 Bioparticles activate dendritic cells and polarize T cell responses to Th1

Author: Charlotte Castenmiller, MSc, Noémi Anna Nagy, MD, Pascal Zion Kroon, MSc, Lydia Auger, Réjean Desgagnés, MSc, Caroline Martel, MSc, Lucie Mirande, MSc, Bertrand Morel, PhD, Joannie Roberge, MSc, Virginie Stordeur, MSc, Guy Tropper, MD, FRCSC, Louis Philipe Vézina, PhD, Ronald van Ree, PhD, Véronique Gomord, PhD, and Esther Christina de Jong, PhD
Subjects: Peanut allergy, Allergen immunotherapy, Dendritic cell, T cell, Microparticle, Immunologic diseases. Allergy, RC581-607
Abstract: Introduction: As the only market-authorized allergen immunotherapy (AIT) for peanut allergy is accompanied by a high risk of side effects and mainly induces robust desensitization without sustained efficacy, novel treatment options are required. Peanut-specific plant-derived eBioparticles (eBPs) surface expressing Ara h 2 at high density have been shown to be very hypoallergenic. Here, we assessed the dendritic cell (DC)-activating and T cell polarization capacity of these peanut-specific eBPs. Methods: Route and kinetics of eBP uptake were studied by (imaging) flow cytometry using monocyte-derived DCs incubated with fluorescently-labelled Ara h 2 eBPs or natural Ara h 2 (nAra h 2) in the presence or absence of inhibitors that block pathways involved in macropinocytosis, phagocytosis, and/or receptor-mediated uptake. DC activation was monitored by flow cytometry (maturation marker expression) and ELISA (cytokine production). T cell polarization was assessed by co-culturing DCs exposed to Ara h 2 eBPs or nAra h 2 with naïve CD4+ T cells, followed by flow cytometry assessment of intracellular IFNγ+ (Th1) and IL-13+ (Th2), and CD25+CD127-Foxp3+ regulatory T cells (Tregs). The suppressive activity of Tregs was tested using a suppressor assay. Results: Ara h 2 eBPs were taken up by DCs through actin-dependent pathways. They activated DCs demonstrated by an induced expression of CD83 and CD86, and production of TNFα, IL-6, and IL-10. eBP-treated DCs polarized naïve CD4+ T cells towards Th1 cells, while reducing Th2 cell development. Furthermore, eBP-treated DCs induced reduced the frequency of Foxp3+ Tregs but did not significantly affect T cell IL-10 production or T cells with suppressive capacity. In contrast, DC activation and Th1 cell polarization were not observed for nAra h 2. Conclusion: Ara h 2 eBPs activate DCs that subsequently promote Th1 cell polarization and reduce Th2 cell polarization. These characteristics mark Ara h 2 eBPs as a promising novel candidate for peanut AIT.
Published: 2023
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3. Lithium in felsic magmas: a volcanological perspective

Author: Maylis Dupont de Dinechin, Hélène Balcone-Boissard, Caroline Martel, and Monika Rusiecka
Subjects: lithium, degassing, geospeedometer, diffusion, plagioclase, brines, Science
Abstract: Volcanic eruptions are unpredictable phenomena that pose a challenge to crisis management, owing to the fact that contrasted eruptive styles (explosive versus effusive) exhibited at the surface depend on unobservable deep processes occurring in the reservoir and the volcanic conduit. Constricting the behaviour of magma during ascent, and the degassing in particular, allows for a clearer understanding of the relationships between petrological and volcano monitoring signals, and hence a better description of the volcanic hazard. To this aim, lithium (Li) has been used to track magmatic and post-eruptive processes, as a geospeedometer for processes operating on short time scales due to its high mobility in silicate melts and crystals. Yet, the accurate use of Li to assess syn- and post-eruptive processes still lack complete dataset. We propose a review of our current knowledge on Li behavior, with an emphasis on felsic (andesitic to rhyolitic) magmas whose explosive behavior during volcanic eruptions is still poorly understood. We present current knowledge regarding the Li concentration and isotopic compositions, intracrystalline diffusion, and crystal-melt-fluid partition coefficients discovered in felsic magmas and primary crystals. We describe difficulties in interpreting Li data to investigate the differentiation, degassing, ascent rate, volatile fluxing, and cooling of magmas. Finally, we suggest future directions for expanding our understanding of Li behavior.
Published: 2023
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4. Syn-Eruptive Conditions of the AD 1530 Sub-Plinian Eruption of La Soufrière of Guadeloupe (Lesser Antilles)

Author: Caroline Martel, Michel Pichavant, Hélène Balcone-Boissard, and Georges Boudon
Subjects: microlite, ascent rate, outgassing, rhyolitic melt, sub-plinian, Science
Abstract: A prerequisite in refining volcanic hazard at explosive volcanoes is a better quantification of the timescales of the syn-eruptive processes, such as magma degassing and crystallization prior to eruption. To this aim, new data on the matrices (microlites, residual glasses, and bubbles) of pumice, scoria, and dense clasts erupted during the AD 1530 andesitic eruption of La Soufrière of Guadeloupe are combined with published data from phase-equilibrium and kinetic experiments, in order to estimate pressures of microlite crystallization and magma ascent rates. From the timescale data, we infer that the AD 1530 eruption started with phreatomagmatic explosions tapping magmas that ascended during about 1 month (decompression rate of ∼50 Pa/s) from the coldest parts of the reservoir (∼825°C and a 74 wt% SiO2 melt). These magmas continuously crystallized microlites (∼25 vol% plagioclase, orthopyroxene, clinopyroxene, magnetite, quartz, and apatite), but did not outgas likely due to sealed conduit margins. The flank collapse (preexisting “cold” edifice) that followed the phreatomagmatic phase triggered a sub-Plinian eruption that progressively tapped the hotter main reservoir (∼875°C and 71 wt% SiO2 interstitial melt), emitting banded and homogeneous pumice. The banded pumice did not significantly outgas and mostly lack decompression-induced microlites, suggesting short ascent durations of the order of 0.5–1 day (decompression rates of 1,400–4,000 Pa/s). The following Strombolian phase emitted dark scoria that did not significantly outgas and only crystallized rare microlites, suggesting ascent duration of the order of 2 days (decompression rates of ∼550 Pa/s). The terminal lava dome growth involved fully outgassed magmas ascended during more than 1 month, giving time for microlite crystallization (∼40 vol% plagioclase, orthopyroxene, clinopyroxene, magnetite, and cristobalite). The detection of any shallow new magmatic intrusion is crucial, since it can trigger a sequence of conduit processes leading to an eruption marked by a succession of different and disastrous eruptive styles, following a scenario similar to the AD 1530 eruption. Overall, we provide a combined approach of petrological, geochemical, and experimental data that may be used to infer ascent conditions and rates at other volcanic systems.
Published: 2021
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5. A System Dynamics Approach to Understanding the deep Magma Plumbing System Beneath Dominica (Lesser Antilles)

Author: Clara Solaro, Hélène Balcone-Boissard, Daniel Joseph Morgan, Georges Boudon, Caroline Martel, and Léa Ostorero
Subjects: orthopyroxenes, Fe-Mg interdiffusion, timescale, plumbing system, crystal system analysis, Dominica (Lesser Antilles), Science
Abstract: To understand the dynamics of magmatic systems, one must first seek to characterize the time-dependent behavior of magma storage and ascent. Herein, we do this through a combination of the Crystal System Approach and careful study of Fe-Mg interdiffusion in orthopyroxene. This allows us to trace the pre-eruptive dynamics of magma plumbing systems, both in space and time. We apply this novel approach on two large silicic eruptions (about 3–5 km3 DRE/eruption) that occurred in the central part of Dominica Island (Lesser Antilles Arc): the eruptions of Layou (∼51 ka) from Morne Diablotins, and Roseau (∼33 ka) from Morne Trois Pitons-Micotrin. For the Roseau eruption, two magmatic environments (MEs) are identified on the basis of orthopyroxene composition, with a dominant reverse-zoning pattern from 50 to 54 to 54–59 mol% enstatite (En), indicating interaction with hotter magma. For the Layou eruption, three MEs are observed as represented by three populations of pyroxenes: En47-51, En51-53 and En53-58. The normal-zoning pathway from En51-53 to En47-51 is significantly registered by crystals, interpreted as convective mixing in a zoned reservoir. The reverse-zoning pathway from En47-51 to En51-53 and also En53-58 is also significantly present, supporting the mixing within the zoned reservoir but also suggesting mixing with a hotter magma, possibly stored in another part of a sub-volcanic mush. The crystal and glass compositions (melt inclusion and matrix glass) from both studied eruptions suggest heating and mixing between different magma pockets located within the mush that were the dominant process for mobilizing eruptible magma. In parallel, we constrain the associated pre-eruptive timescales by modeling the diffusive relaxation of Fe-Mg chemical gradients that originated within the zonation of the same orthopyroxene crystals. Diffusion modeling was considered along the b-axis of 66 zoned orthopyroxene crystals for these two eruptions, at a magmatic temperature of 850 ± 25°C. In light of these results, we propose that the Layou and the Roseau magma reservoirs were rejuvenated and heated by ∼25–50°C about 10 years prior to eruption by the injection of an underplating, hotter magma, creating the observed dominant reverse-zoning patterns of the erupted orthopyroxenes. We thus have evidence that silicic mush can be re-mobilized over timescales of decades prior to eruption, as previously suggested for Santorini and Taupo volcanoes.
Published: 2020
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6. Theoretical Models of Decompression-Induced Plagioclase Nucleation and Growth in Hydrated Silica-Rich Melts

Author: Edith Mollard, Caroline Martel, Emmanuel Le Trong, and Grégory Rogerie
Subjects: plagioclase, undercooling, nucleation and growth, diffusion, modeling, Science
Abstract: Magma ascending from the storage region toward the surface may crystallize small and rapidly-grown crystals, designated as microlites. Upon decompression, the rapid changes of the microlite textures, such as number density and crystal size, directly impact the rheology of the magma in the volcanic conduit, and eventually control the effusive vs. explosive style of the subaerial eruption. This is of prime importance for volcanic risk assessment involving highly viscous silica-rich magmas that are prone to fragmentation. To this aim, we present a theoretical modeling of plagioclase nucleation and growth in rhyolitic-like melts, based on previous decompression experiments. Thus, the modeling is valid for plagioclase crystallization in rhyolitic melts decompressed at 875°C from 200 MPa to final pressures of 50, 75, or 100 MPa, which represents effective undercooling (ΔTeff) of 110, 80 and 55°C, respectively. Our results of nucleation-rate calculation using the Classical Nucleation Theory (CNT; case of homogeneous nucleation) and values of crystal-melt interfacial energy (σ) either from literature or empirically calculated, strongly disagree with previously-determined experimental nucleation rates. By inverting the CNT calculation using the experimentally-determined nucleation rates, we propose plagioclase-liquid interfacial energies from 0.041 to 0.059 J.m−2 with ΔTeff increasing from 55 to 110°C, which is about 2–3 times lower than σ determined empirically and macroscopically. We modeled plagioclase growth rates by atom diffusion in melt (following Fick's second law adapted to multicomponent systems), considering a crystal-melt interface advancing over time (as crystal grows) and a chemically-closed finite reservoir (no component supply). The component limiting plagioclase growth has been determined to be CaO, for which we calculated diffusion coefficients from 10−14 to 10−15 m2/s (conditions of a silicic melt, 875°C, and H2O saturation pressures from 50 to 100 MPa). The overall good agreement between the model and the experimental growth laws validates diffusion as the main process controlling isothermal decompression-induced plagioclase growth under moderate ΔTeff < 110°C. Combining both calculations, crystal number density and size, may be relevant to predict plagioclase microlite textures in ascending rhyolitic magmas, which may now be incorporated in conduit flow models to assess the magma rheological behavior that controls eruption dynamics.
Published: 2020
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7. Hepatocyte SHP-1 is a Critical Modulator of Inflammation During Endotoxemia

Author: Anupam Adhikari, Caroline Martel, André Marette, and Martin Olivier
Subjects: Medicine, Science
Abstract: Abstract Liver hepatocytes (Hep) are known to be central players during the inflammatory response to systemic infection. Interestingly, the protein tyrosine phosphatases (PTP) SHP-1, has been recognized as a major regulator of inflammation; however their implication in the control of Hep-mediated inflammatory response is still unknown. To study its implication in the regulation of the Hep-mediated inflammatory response during endotoxemia, Cre-Lox mice with a Hep-specific Ptpn6 deletion (Ptpn6 H-KO ) were injected with LPS. In contrast to the wild-type mice (Ptpn6 f/f ) that started to die by 24 hrs post-inoculation, the Ptpn6 H-KO mice exhibited mortality by 6 hrs. In parallel, higher amounts of metabolic markers, pro-inflammatory mediators and circulating cytokines were detected in Ptpn6 H-KO mice. Primary Hep obtained from Ptpn6 H-KO , also showed increased secretion of pro-inflammatory cytokines and nitric oxide (NO) comparatively to its wild type (Ptpn6 f/f ) counterpart. Pharmacological approaches to block TNF-α and NO production protected both the Ptpn6 f/f and the Ptpn6 H-KO mice against deadly LPS-mediated endotoxemia. Collectively, these results establish hepatocyte SHP-1 is a critical player regulating systemic inflammation. Our findings further suggest that SHP-1 activation could represent a new therapeutic avenue to better control inflammatory-related pathologies.
Published: 2017
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8. Cysteine Peptidase B Regulates Leishmania mexicana Virulence through the Modulation of GP63 Expression.

Author: Pierre-André Casgrain, Caroline Martel, W Robert McMaster, Jeremy C Mottram, Martin Olivier, and Albert Descoteaux
Subjects: Immunologic diseases. Allergy, RC581-607, Biology (General), QH301-705.5
Abstract: Cysteine peptidases play a central role in the biology of Leishmania. In this work, we sought to further elucidate the mechanism(s) by which the cysteine peptidase CPB contributes to L. mexicana virulence and whether CPB participates in the formation of large communal parasitophorous vacuoles induced by these parasites. We initially examined the impact of L. mexicana infection on the trafficking of VAMP3 and VAMP8, two endocytic SNARE proteins associated with phagolysosome biogenesis and function. Using a CPB-deficient mutant, we found that both VAMP3 and VAMP8 were down-modulated in a CPB-dependent manner. We also discovered that expression of the virulence-associated GPI-anchored metalloprotease GP63 was inhibited in the absence of CPB. Expression of GP63 in the CPB-deficient mutant was sufficient to down-modulate VAMP3 and VAMP8. Similarly, episomal expression of GP63 enabled the CPB-deficient mutant to establish infection in macrophages, induce the formation of large communal parasitophorous vacuoles, and cause lesions in mice. These findings implicate CPB in the regulation of GP63 expression and provide evidence that both GP63 and CPB are key virulence factors in L. mexicana.
Published: 2016
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9. Impact of Leishmania mexicana infection on dendritic cell signaling and functions.

Author: Irazú Contreras, José A Estrada, Hannah Guak, Caroline Martel, Alborz Borjian, Benjamin Ralph, Marina T Shio, Sylvie Fournier, Connie M Krawczyk, and Martin Olivier
Subjects: Arctic medicine. Tropical medicine, RC955-962, Public aspects of medicine, RA1-1270
Abstract: Leishmania parasites have the ability to modify macrophage signaling pathways in order to survive and multiply within its mammalian host. They are also known to invade other cells including neutrophils, fibroblasts and dendritic cells (DCs). DCs have an important role in immunity as the link between innate and adaptive immunity, necessary for the development of an effective response; however, the impact of Leishmania mexicana infection on DCs has been poorly studied. Herein, we report that Leishmania infection rapidly induced DC protein tyrosine phosphatases activity, leading to MAP kinases inactivation. In line with this, L. mexicana was found to decrease the nuclear translocation of transcription factors such as AP-1 and NF-κB. Concomitantly, L. mexicana-infected DCs showed reduced expression of several surface antigen-presenting and co-stimulatory molecules upon LPS stimulation. Leishmania-induced interference on DC maturation was further reflected by their reduced capacity to present OVA antigen to OVA-specific T cells, as shown by abrogation of IL-2 production by the T cells. Collectively, our data revealed that DC infection by L. mexicana appears to affect the cellular and immunological mechanisms necessary for the development of an effective and protective immune response, therefore favouring the survival and propagation of the parasite within its host.
Published: 2014
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10. Absence of metalloprotease GP63 alters the protein content of Leishmania exosomes.

Author: Kasra Hassani, Marina Tiemi Shio, Caroline Martel, Denis Faubert, and Martin Olivier
Subjects: Medicine, Science
Abstract: Protozoan parasites of Leishmania genus are able to successfully infect their host macrophage due to multiple virulence strategies that result in its deactivation. Recent studies suggest Leishmania GP63 to be a critical virulence factor in modulation of many macrophage molecules, including protein tyrosine phosphatases (PTPs) and transcription factors (TFs). Additionally, we and others recently reported that Leishmania-released exosomes can participate in pathogenesis. Exosomes are 40-100 nm vesicles that are freed by many eukaryotic cells. To better understand the GP63-dependent immune modulation of the macrophage by Leishmania parasites and their exosomes, we compared the immunomodulatory properties of Leishmania major (WT) and L. major gp63-/- (KO) as well as their exosomes in vitro and in vivo. Importantly, we observed that Leishmania exosomes can modulate macrophage PTPs and TFs in a GP63-dependent manner. In addition, our qRT-PCR analyses showed that WT parasites were able to downregulate multiple genes involved in the immune response, especially cytokines and pattern recognition receptors. KO parasites showed a strongly reduced modulatory capacity compared to WT parasites. Furthermore, comparison of WT versus KO exosomes also showed divergences in alteration of gene expression, especially of chemokine receptors. In parallel, studying the in vivo inflammatory recruitment using a murine air pouch model, we found that exosomes have stronger proinflammatory properties than parasites and preferentially induce the recruitment of neutrophils. Finally, comparative proteomics of WT and KO exosomes surprisingly revealed major differences in their protein content, suggesting a role for GP63 in Leishmania exosomal protein sorting. Collectively our data clearly establish the crucial role of GP63 in dampening the innate inflammatory response during early Leishmania infection, and also provides new insights in regard to the role and biology of exosomes in Leishmania host-parasite interactions.
Published: 2014
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11. Synthetic Plasmodium-like hemozoin activates the immune response: a morphology - function study.

Author: Maritza Jaramillo, Marie-Josée Bellemare, Caroline Martel, Marina Tiemi Shio, Ana Paulina Contreras, Marianne Godbout, Michel Roger, Eric Gaudreault, Jean Gosselin, D Scott Bohle, and Martin Olivier
Subjects: Medicine, Science
Abstract: Increasing evidence points to an important role for hemozoin (HZ), the malaria pigment, in the immunopathology related to this infection. However, there is no consensus as to whether HZ exerts its immunostimulatory activity in absence of other parasite or host components. Contamination of native HZ preparations and the lack of a unified protocol to produce crystals that mimic those of Plasmodium HZ (PHZ) are major technical limitants when performing functional studies with HZ. In fact, the most commonly used methods generate a heterogeneous nanocrystalline material. Thus, it is likely that such aggregates do not resemble to PHZ and differ in their inflammatory properties. To address this issue, the present study was designed to establish whether synthetic HZ (sHZ) crystals produced by different methods vary in their morphology and in their ability to activate immune responses. We report a new method of HZ synthesis (the precise aqueous acid-catalyzed method) that yields homogeneous sHZ crystals (Plasmodium-like HZ) which are very similar to PHZ in their size and physicochemical properties. Importantly, these crystals are devoid of protein and DNA contamination. Of interest, structure-function studies revealed that the size and shape of the synthetic crystals influences their ability to activate inflammatory responses (e.g. nitric oxide, chemokine and cytokine mRNA) in vitro and in vivo. In summary, our data confirm that sHZ possesses immunostimulatory properties and underline the importance of verifying by electron microscopy both the morphology and homogeneity of the synthetic crystals to ensure that they closely resemble those of the parasite. Periodic quality control experiments and unification of the method of HZ synthesis are key steps to unravel the role of HZ in malaria immunopathology.
Published: 2009
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12. Correction: Synthetic -Like Hemozoin Activates the Immune Response: A Morphology - Function Study.

Author: Maritza Jaramillo, Marie-Josée Bellemare, Caroline Martel, Marina Tiemi Shio, Ana Paulina Contreras, Marianne Godbout, Michel Roger, Eric Gaudreault, Jean Gosselin, D. Scott Bohle, and Martin Olivier
Subjects: Medicine, Science
Published: 2009
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13. Fel d 1 surface expression on plant-made eBioparticles combines potent immune activation and hypoallergenicity

Author: Stefanie Busold, Lorenz Aglas, Charlotte Menage, Lydia Auger, Réjean Desgagnés, Loïc Faye, Anne‐Catherine Fitchette, Esther C. de Jong, Caroline Martel, Maria Stigler, Virginie Catala‐Stordeur, Guy Tropper, Louis‐Philippe Vézina, Véronique Gomord, Teunis B. H. Geijtenbeek, Ronald van Ree, Experimental Immunology, Graduate School, AII - Infectious diseases, AII - Inflammatory diseases, Infectious diseases, AII - Cancer immunology, Ear, Nose and Throat, APH - Global Health, APH - Personalized Medicine, and Molecular cell biology and Immunology
Subjects: Immunology, Humans, Immunology and Allergy, Allergens, Immunoglobulin E
Published: 2022

14. Connectivity of the corticostriatal and thalamostriatal systems in normal and parkinsonian states: An update

Author: Anne-Caroline Martel and Adriana Galvan
Subjects: Cerebral Cortex, Neurons, Neurology, Thalamus, Neural Pathways, Humans, Parkinson Disease, Corpus Striatum
Abstract: The striatum receives abundant glutamatergic afferents from the cortex and thalamus. These inputs play a major role in the functions of the striatal neurons in normal conditions, and are significantly altered in pathological states, such as Parkinson's disease. This review summarizes the current knowledge of the connectivity of the corticostriatal and thalamostriatal pathways, with emphasis on the most recent advances in the field. We also discuss novel findings regarding structural changes in cortico- and thalamostriatal connections that occur in these connections as a consequence of striatal loss of dopamine in parkinsonism.
Published: 2022

15. Moving Image

Author: CAROLINE MARTEL
Published: 2022
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16. Nucleation delay in water-saturated rhyolite during decompression in shallow volcanic systems and its implications for ascent dynamics

Author: Monika K. Rusiecka and Caroline Martel
Subjects: Geochemistry and Petrology
Published: 2022
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17. Temporal processing in the striatum: Interplay between midbrain dopamine neurons and striatal cholinergic interneurons

Author: Paul Apicella, Anne-Caroline Martel, Institut de Neurosciences de la Timone (INT), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and apicella, paul
Subjects: Cholinergic Agents, non-human primate, Striatum, Biology, neuronal recording, Midbrain, [SCCO]Cognitive science, 03 medical and health sciences, 0302 clinical medicine, Interneurons, Mesencephalon, Dopamine, Basal ganglia, medicine, Animals, Premovement neuronal activity, ComputingMilieux_MISCELLANEOUS, interval timing, 030304 developmental biology, 0303 health sciences, Dopaminergic Neurons, [SCCO.NEUR]Cognitive science/Neuroscience, General Neuroscience, [SCCO.NEUR] Cognitive science/Neuroscience, rodent, [SCCO] Cognitive science, Cholinergic Neurons, Corpus Striatum, Electrophysiology, nervous system, Time Perception, basal ganglia, Synaptic plasticity, Cholinergic, Neuroscience, 030217 neurology & neurosurgery, medicine.drug
Abstract: There has been considerable progress in recent years toward understanding the neuronal mechanisms mediating time perception. Notably, the striatum and its dopamine (DA) input from the ventral midbrain are considered to be central for timing on the scale of hundreds of milliseconds and seconds. The cholinergic interneurons (ChIs) of the striatum provide an extensive local innervation, which closely interacts with striatal DA afferents. Both neuronal systems have been shown to influence synaptic plasticity to shape the transfer of information through the striatum. Given their cooperative role in regulating striatal output pathways, DA and cholinergic inputs may have distinct but complementary roles in timing processes. Electrophysiological recordings from behaving animals have provided evidence that responses of midbrain DA neurons and striatal tonically active neurons (TANs), presumed ChIs, to motivationally relevant events are sensitive to the predicted time of these events; namely, changes in neuronal activity are reduced or absent at times when events are more expected, indicating that temporal aspects of prediction play an important role in the responsiveness of these two neuronal systems. Recently, new findings have further suggested that DA neurons and cholinergic TANs are both involved in the ability to keep track of the elapsed time. These two systems appear to work in parallel in initiating the timing process at the beginning of an interval to be timed. It therefore appears that DA and ChI signaling could participate in striatal processing that is crucial for the control of timing behavior.
Published: 2020
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18. Spectacles du monde

Author: Caroline Martel
Published: 2022
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19. Spectacles of the World

Author: Caroline Martel
Published: 2022
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20. Nucleation delay of feldspar in water saturated rhyolite during decompression in shallow volcanic systems

Author: Monika Rusiecka and Caroline Martel
Published: 2022
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21. Corrigendum to: 'Connectivity of the Corticostriatal and Thalamostriatal Systems in Normal and Parkinsonian States: An Update' Neurobiology of Disease 174: 105878

Author: Anne-Caroline Martel and Adriana Galvan
Subjects: Neurology
Published: 2023
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22. Experimental Constraints on the Crystallization of Silica Phases in Silicic Magmas

Author: Rémi Champallier, Karine Devineau, J M Castro, Caroline Martel, Alexandra R. L. Kushnir, Guillaume Wille, V. O. Davydova, Michel Pichavant, I Di Carlo, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Johannes Gutenberg - Universität Mainz (JGU), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Lomonosov Moscow State University (MSU), Ecole et Observatoire des Sciences de la Terre (EOST), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), CNRS-INSU_TelluS program, ANR-11-EQPX-0036,PLANEX,Planète Expérimentation: simulation et analyse in-situ en conditions extrêmes(2011), and ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
Subjects: 010504 meteorology & atmospheric sciences, silica polymorph, crystallization, Silicic, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 010502 geochemistry & geophysics, 01 natural sciences, law.invention, metastability, Geophysics, Chemical engineering, eruptive dynamics, Geochemistry and Petrology, law, [SDU]Sciences of the Universe [physics], [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Crystallization, Geology, silicic magma, 0105 earth and related environmental sciences
Abstract: Low-pressure silica polymorphs, e.g. quartz (Qtz), tridymite (Trd), and cristobalite (Crs), are common in silicic magmas, but the conditions of their formation are still unclear. The stability fields of these polymorphs have been determined in the SiO2, SiO2–H2O, and haplogranite systems, but these simple systems are not directly applicable to silica polymorph crystallization in natural silicic magmas. The present study compiles an experimental database of new and previously-published data documenting the crystallization of silica phases in natural silicic magmas and simple synthetic systems. Silica polymorphs are identified using Raman spectroscopy and their pressure-temperature domains of occurrence and chemical compositions are determined at pressures between 0·1 and 200 MPa, temperatures between 685 to 1200° C, and under H2O-saturated and H2O-undersaturated conditions. Qtz is the stable silica polymorph at pressures higher than 25–30 MPa, temperatures between ∼700 and 950° C, and occurs for a narrow range of melt SiO2 contents (∼79–81 wt %). Constraints on Qtz stability derived from simple systems are mutually compatible with, and thus applicable to natural compositions. This is consistent with Qtz compositions being close to ‘pure’ SiO2, both in experiments and nature. In volcanic systems, Qtz crystallization may occur in magmatic reservoirs and deep volcanic conduits. Trd did not crystallize in the experiments conducted as part of this study despite several experiments having been performed in the Trd stability field. This is consistent with results from the literature which show that Trd crystallization is kinetically inhibited in particular relative to Crs. Natural Trd have compositions deviating substantially from ‘pure’ SiO2, so that stability limits determined in simple systems should not be applied directly to natural cases. Crs was encountered at pressures below 20–30 MPa (or H2O contents < ∼1·5 wt %), from sub-solidus (∼800° C) to near-liquidus (up to 1040° C), and coexisting with melts having a large range of SiO2 contents (70–81 wt %). The Crs stability field is much larger in natural magmas compared to pure SiO2 systems. Crs is a metastable phase stabilized by components (Al, Na, K; about 3 wt %) present in the silicic melt. In volcanic systems, Crs crystallization may thus be restricted to subsurface manifestations such as lava domes.
Published: 2021
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23. Sulphur behaviour and oxygen fugacity variation in Mt. Etna system revealed by melt inclusions

Author: Caroline Martel, Yves Moussallam, Giada Iacono-Marziano, Antonio Paonita, Nial Peters, Emanuela Gennaro, and Michel Pichavant
Subjects: Mineral redox buffer, Chemistry, Mineralogy, chemistry.chemical_element, Variation (astronomy), Sulfur, Melt inclusions
Published: 2021
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24. Impact of T161, Y318 and S363 alanine mutations on regulation of the human delta-opioid receptor (hDOPr) induced by peptidic and alkaloid agonists

Author: Quentin Dupas, Nicolas Elie, Stéphane Allouche, Elise Camacho, Géza Tóth, Christophe Rochais, Caroline Martel, Marie Nowoczyn, Nicolas Marie, Signalisation, électrophysiologie et imagerie des lésions d’ischémie-reperfusion myocardique (SEILIRM), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU), Neuropsychopharmacologie des addictions. Vulnérabilité et variabilité expérimentale et clinique (NAVVEC - UM 81 (UMR 8206/ U705)), Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris Descartes - Paris 5 (UPD5)-Institut des sciences du Médicament -Toxicologie - Chimie - Environnement (IFR71), Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Paris Descartes - Paris 5 (UPD5)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Paris Descartes - Paris 5 (UPD5)-Université Paris Diderot - Paris 7 (UPD7), Interactions Cellules Organismes Environnement (ICORE), CHU Caen, Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Normandie Université (NU)-Tumorothèque de Caen Basse-Normandie (TCBN)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Centre d'Etudes et de Recherche sur le Médicament de Normandie (CERMN), and Biological Research Centre [Szeged] (BRC)
Subjects: 0301 basic medicine, Opioid receptor regulation, Enkephalin, media_common.quotation_subject, Desensitization, Biased agonism, δ-opioid receptor, 03 medical and health sciences, Cellular and Molecular Neuroscience, 0302 clinical medicine, Alkaloids, Receptors, Opioid, delta, medicine, Arrestin, Functional selectivity, Humans, Phosphorylation, Receptor, Internalization, media_common, Pharmacology, Alanine, Chemistry, Wild type, Cell biology, Analgesics, Opioid, 030104 developmental biology, HEK293 Cells, Etorphine, Mutation, [SDV.SP.PHARMA]Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology, 030217 neurology & neurosurgery, medicine.drug, Protein Binding
Abstract: International audience; Previously, we showed a differential regulation of the human delta-opioid receptor (hDOPr) by etorphine and [D-Pen2, D-Pen5] enkephalin (DPDPE). To understand the molecular basis of such differences, we introduced 3 alanine mutations at the residues T161. Y318 and S363. Both wild type (WT) and hDOPr mutants were expressed in HEK cells containing endogenous arrestins or CFP-tagged arrestin 3, then desensitization, internalization, recycling and phosphorylation were studied. In a context of endogenous arrestin expression, a major difference in DOPr desensitization was observed between agonists that was modified with the T161A mutation upon etorphine and with the S363A substitution upon DPDPE exposure. While both agonists induced a major receptor internalization, T161A and S363A impaired DOPr sequestration only for etorphine. However, similar level of S363 phosphorylation was measured between agonists. When CFP-tagged arrestin 3 was over-expressed, a similar profile of desensitization was measured for both agonists. In this context, all the 3 alanine mutations decreased etorphine-induced receptor desensitization. Using FRET, we showed similar interactions between WT hDOPr and arrestin 3 under DPDPE and etorphine stimulation which were delayed by both the Y318A and the S363A substitutions for etorphine. Finally, hDOPr recycling was qualitatively evaluated by microscopy and showed neither arrestin 3/hDOPr colocalization nor major impact of alanine mutations except for the S363A which impaired internalization and recycling for etorphine. The T161, Y318 and S363 residues of hDOPr could underlie the differential regulation promoted by DPDPE and etorphine
Published: 2020
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25. Estimation of vector competence of Moroccan Sand fly Populations Using a Proteomic Approach

Author: George Dong, Mohamed Hafidi, Ali Boumezzough, Mohamed Daoudi, S. Boussaa, Martin Olivier, and Caroline Martel
Subjects: business.industry, Computer science, Artificial intelligence, business, Machine learning, computer.software_genre, Competence (human resources), computer
Abstract: Background Phlebotomine vector born disease are distributed throughout the world, and different pathogens are associated with varying degrees of disease severity. In Morocco, sand fly populations are incriminated in the transmission of several pathogens, such Leishmania spp. and phlebovirus, in particular the most relevant sand fly species as the case of Phlebotomus papatasi. This species is the main vector of Leishmania major in Morocco, and incriminated in phlebovirus transmission. Not to pass over without investigating its possible role on the transmission of entomopathogenic parasite already reported in literature. Methodology and finding The present study focused on proteomic analysis in Phlebotomus papatasi from four localities in Morocco. Proteomic analysis in female P. papatasi was performed with Liquid chromatography-tandem mass spectrometry (LC-MS/MS). A total of 239 identified proteins for Leishmania spp., 26 identified proteins for phlebovirus and 1132 identified proteins for nematode were detected in the 20 pools of P. papatasi from investigated localities. The microscopic examination of 1752 sandflies collected showed, the infection of two specimens of female’s P. sergenti with Tetranematid Didilia spp. and potential Microfilariae in Imintanout locality (Z2).Conclusion This study presents the first report of nematodes in sand flies of Africa. Also, the first use of proteomic tools for estimation of vector competence of P. papatasi which could be a specific tool to a better understanding of the vectorial capacity of Moroccan sandflies population.
Published: 2020
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26. Targeted Transgene Expression in Cholinergic Interneurons in the Monkey Striatum Using Canine Adenovirus Serotype 2 Vectors

Author: Anne-Caroline Martel, Heba Elseedy, Marina Lavigne, Jennyfer Scapula, Antoine Ghestem, Eric J. Kremer, Monique Esclapez, and Paul Apicella
Subjects: viral vector transduction, nervous system, basal ganglia, nonhuman primate, microcircuit analysis, lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry, acetylcholine, lcsh:RC321-571
Abstract: The striatum, the main input structure of the basal ganglia, is critical for action selection and adaptive motor control. To understand the neuronal mechanisms underlying these functions, an analysis of microcircuits that compose the striatum is necessary. Among these, cholinergic interneurons (ChIs) provide intrinsic striatal innervation whose dysfunction is implicated in neuropsychiatric diseases, such as Parkinson’s disease and Tourette syndrome. The ability to experimentally manipulate the activity of ChIs is critical to gain insights into their contribution to the normal function of the striatum and the emergence of behavioral abnormalities in pathological states. In this study, we generated and tested CAV-pChAT-GFP, a replication-defective canine adenovirus type 2 (CAV-2) vector carrying the green fluorescent protein (GFP) sequence under the control of the human choline acetyltransferase (ChAT) promoter. We first tested the potential specificity of CAV-pChAT-GFP to label striatal ChIs in a rat before performing experiments on two macaque monkeys. In the vector-injected rat and monkey striatum, we found that GFP expression preferentially colocalized with ChAT-immunoreactivity throughout the striatum, including those from local circuit interneurons. CAV-2 vectors containing transgene driven by the ChAT promoter provide a powerful tool for investigating ChI contributions to circuit function and behavior in nonhuman primates.
Published: 2020
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27. Author response for 'Temporal processing in the striatum: interplay between midbrain dopamine neurons and striatal cholinergic interneurons'

Author: Anne-Caroline Martel and Paul Apicella
Subjects: Midbrain, Dopamine, medicine, Cholinergic, Striatum, Biology, Neuroscience, medicine.drug
Published: 2020
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28. Dominica: transcrustal magmatic system and eruptive halogen budgets

Author: Thiebaut d'Augustin, Hélène Balcone-Boissard, Georges Boudon, Caroline Martel, Etienne Deloule, and Pierre Bürckel
Abstract: Dominica island experienced the largest explosive eruptions (ignimbrites) of the Lesser Antilles arc. The recent revised chronostratigraphy of the Morne Trois Pitons – Micotrin eruptive activity evidenced a series of plinian eruptions that occurred between 18 ka and 9 ka BP. Here we focus on these recent eruptions in order to determine the magma storage conditions at depth and volatile degassing budget. Volatile concentrations (H2O, CO2) in melt inclusions indicate storage conditions of 200 MPa (~6-8 km deep) and 860-880°C in agreement with experimental constraints from phase-equilibrium data. The magmas were thus stored shallower than those involved during the ignimbritic eruptions (~16 km deep). Magma composition and halogen ratios suggest a common magma origin for all eruptions of Morne Trois Pitons Micotrin volcano in the last 60 kyrs. In addition, for the first time, a complete degassing budget including H2O, CO2, SO2, F, Cl, and Br has been established for all these explosive eruptions. The estimation of their eruptive fluxes towards the atmosphere supports the potential important role of halogen elements in the modification of atmosphere chemistry. Br degassing budget was the same order of magnitude as S whereas F and Cl budgets were 1 and 2 orders of magnitude higher than these two species.
Published: 2020
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29. The role of oxides in the shallow vesiculation of ascending magmas

Author: Caroline Martel, Mathieu Colombier, Alain Burgisser, Laurent Arbaret, Mélanie Forien, Institut des Sciences de la Terre (ISTerre), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Gustave Eiffel-Université Grenoble Alpes (UGA), Magma - UMR7327, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), The Arctic University of Norway (UiT), Ludwig-Maximilians-Universität München (LMU), ANR-10-LABX-0056,OSUG@2020,Innovative strategies for observing and modelling natural systems(2010), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and The Arctic University of Norway [Tromsø, Norway] (UiT)
Subjects: Lateral eruption, 010504 meteorology & atmospheric sciences, Nucleation, Trachyte, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Microlite, Vulcanian explosion, Geochemistry and Petrology, Pumice, Rhyolite, VDP::Matematikk og Naturvitenskap: 400::Geofag: 450, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Petrology, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, VDP::Mathematics and natural science: 400::Geosciences: 450, Number density, Lava dome, Fe-Ti oxides, Dome eruption, Geophysics, Volcano, 13. Climate action, engineering, Bubbles, Geology
Abstract: Accepted manuscript version, licensed CC BY-NC-ND 4.0. Despite their generally low volume fraction, Fesingle bondTi oxides have the potential to greatly influence the eruptive style because they lower the supersaturation pressure for heterogeneous bubble nucleation. Once nucleated, bubbles respond fast to pressure changes, fostering rapid expansion and explosive behavior. Yet, oxide microlite quantifications are often absent from data of explosive products. We used new, re-analyzed, and published data to build a compilation of oxide number densities (ONDs) and vesicle number densities (VNDs) of trachytic and calc-alkaline products. Four eruptive styles were selected: 1) Vulcanian explosions from Soufrière Hills volcano, Montserrat, Lascar volcano, Chile, and Kilian volcano, France, 2) blasts from Mt. Pelée volcano, Lesser Antilles, Mount St. Helens, USA, and Merapi volcano, Indonesia, 3) a sub-Plinian explosion from Merapi volcano, and 4) lava dome effusions with intermittent collapse from Soufrière Hills and Mt. Pelée volcanoes. Natural samples were separated into two groups according to the dominant texture of the products of each event: 1) vesicular pumice clasts from explosions with a strong vertical component and 2) dense clasts with diktytaxitic textures from dome collapse event and lateral blast. Group 1 samples are either distributed alongside the 1:1 trend between VND and OND that spans from 1015 to 1017 m−3, or have a constant VND of 1016–16.5 m−3 regardless of OND. A large proportion of oxides (55–100%) touch vesicles. A more variable proportion of vesicles (16–72%) are in contact with oxides because of syn-explosive growth and coalescence. Group 2 samples have ONDs in the same broad range as group 1 samples. We also used new and published data to build a compilation of ONDs and VNDs of five series of experimental decompression of rhyolitic and phonolitic melts. In samples with OND ≈ VND, most bubbles are in contact with more than one oxide and 64–88% of the oxides are in contact with bubbles. Such high levels of connectivity suggest that the role of oxides in controlling bubble nucleation has been underestimated. When VND ≥ OND, nucleation densities of experimental vesicles can be reproduced by heterogeneous nucleation models, which we used to calculate syn-explosive decompression rates from VNDs at Merapi, Soufrière Hills, and Kilian. These rates and textural evidence suggest that the decompression front accompanying these Vulcanian and sub-Plinian explosions is responsible for syn-explosive bubble nucleation. We calculated the average pre-explosive ascent rates necessary to yield the observed ONDs at Soufrière Hills and Merapi volcanoes. The resulting rates, 0.005–20 m/s, overlap considerably with the range of critical ascent rate inferred for the effusive–explosive transition, supporting the hypothesis that this transition is primarily controlled by oxide microlites in the conduit because oxides are a primer for explosive behavior when present in sufficiently high number densities. Focusing on the older eruption of Kilian, for which no observation is available, we infer that pre-explosive ascent rates of >7 × 10−3 m/s were necessary for explosive behavior to occur.
Published: 2020
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30. Theoretical Models of Decompression-Induced Plagioclase Nucleation and Growth in Hydrated Silica-Rich Melts

Author: Emmanuel Le Trong, Caroline Martel, Grégory Rogerie, Edith Mollard, Magma - UMR7327, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and ANR-05-CATT-0004,IONONAMI,IONONAMI : détection ionosphèrique et directe de tsunamis par radar OTH et par systèmes spatiaux(2005)
Subjects: Materials science, 010504 meteorology & atmospheric sciences, Diffusion, Nucleation, Thermodynamics, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Isothermal process, law.invention, Microlite, law, undercooling, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Plagioclase, Crystallization, lcsh:Science, Supercooling, 0105 earth and related environmental sciences, nucleation and growth, diffusion, modeling, engineering, General Earth and Planetary Sciences, lcsh:Q, Classical nucleation theory, plagioclase
Abstract: International audience; Magma ascending from the storage region toward the surface may crystallize small and rapidly-grown crystals, designated as microlites. Upon decompression, the rapid changes of the microlite textures, such as number density and crystal size, directly impact the rheology of the magma in the volcanic conduit, and eventually control the effusive vs. explosive style of the subaerial eruption. This is of prime importance for volcanic risk assessment involving highly viscous silica-rich magmas that are prone to fragmentation. To this aim, we present a theoretical modeling of plagioclase nucleation and growth in rhyolitic-like melts, based on previous decompression experiments. Thus, the modeling is valid for plagioclase crystallization in rhyolitic melts decompressed at 875 • C from 200 MPa to final pressures of 50, 75, or 100 MPa, which represents effective undercooling (T eff) of 110, 80 and 55 • C, respectively. Our results of nucleation-rate calculation using the Classical Nucleation Theory (CNT; case of homogeneous nucleation) and values of crystal-melt interfacial energy (σ) either from literature or empirically calculated, strongly disagree with previously-determined experimental nucleation rates. By inverting the CNT calculation using the experimentally-determined nucleation rates, we propose plagioclase-liquid interfacial energies from 0.041 to 0.059 J.m −2 with T eff increasing from 55 to 110 • C, which is about 2-3 times lower than σ determined empirically and macroscopically. We modeled plagioclase growth rates by atom diffusion in melt (following Fick's second law adapted to multicomponent systems), considering a crystal-melt interface advancing over time (as crystal grows) and a chemically-closed finite reservoir (no component supply). The component limiting plagioclase growth has been determined to be CaO, for which we calculated diffusion coefficients from 10 −14 to 10 −15 m 2 /s (conditions of a silicic melt, 875 • C, and H 2 O saturation pressures from 50 to 100 MPa). The overall good agreement between the model and the experimental growth laws validates diffusion as the main process controlling isothermal decompression-induced plagioclase growth under moderate T eff < 110 • C. Combining both calculations, crystal number density and size, may be relevant to predict plagioclase microlite textures in ascending rhyolitic magmas, which may now be incorporated in conduit flow models to assess the magma rheological behavior that controls eruption dynamics.
Published: 2020
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31. Surface Expression of Major Allergens on Plant-Made eBioparticle Combines Hypo-Allergenicity with Potent Immune Activation

Author: Stefanie Busold, Lorenz Aglas, Charlotte Menage, Lydia Auger, Réjean Desgagnés, Loïc Faye, Anne-Catherine Fitchette, Esther de Jong, Caroline Martel, Maria Stigler, Virginie Stordeur, Guy Tropper, Serge Versteeg, Louis Vézina, Véronique Gomord, Teunis Geijtenbeek, and Ronald van Ree
Subjects: Immunology, Immunology and Allergy
Published: 2022
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32. Storage conditions of the mafic and silicic magmas at Cotopaxi, Ecuador

Author: Patricia Mothes, Indira Molina, Joan Andújar, Bruno Scaillet, Caroline Martel, Michel Pichavant, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), instituto Geofísico, Escuela Politécnica Nacional (EPN), and European Project: 282759,EC:FP7:ENV,FP7-ENV-2011,VUELCO(2011)
Subjects: Rhyolite, Experimental petrology, 010504 meteorology & atmospheric sciences, Cotopaxi, Lava, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Silicic, Pyroclastic rock, 010502 geochemistry & geophysics, 01 natural sciences, Eruptive dynamics, Geochemistry and Petrology, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, 0105 earth and related environmental sciences, Fractional crystallization (geology), biology, Andesites, Andesite, biology.organism_classification, Geophysics, [SDU]Sciences of the Universe [physics], 13. Climate action, Phenocryst, Scoria, Mafic, Geology
Abstract: International audience; The 2015 reactivation of the Cotopaxi volcano urges us to understand the complex eruptive dynamics of Cotopaxi for better management of a potential major crisis in the near future. Cotopaxi has commonly transitioned from andesitic eruptions of strombolian style (lava flows and scoria ballistics) or nuées ardentes (pyroclastic flows and ash falls) to highly explosive rhyolitic ignimbrites (pumiceous pyroclastic flows), which entail drastically different risks. To better interpret geophysical and geochemical signals, Cotopaxi magma storage conditions were determined via existing phase-equilibrium experiments that used starting materials chemically close to the Cotopaxi andesites and rhyolites. The results suggest that Cotopaxi's most mafic andesites (last erupted products) can be stored over a large range of depth from ~7 km to ≥16 km below the summit (pressure from ~200 to ≥400 MPa), 1000 °C, NNO +2, and contain 4.5–6.0±0.7 wt% H2O dissolved in the melt in equilibrium with ~30–40% phenocrysts of plagioclase, two pyroxenes, and Fe-Ti oxides. These mafic andesites sometimes evolve towards more silicic andesites by cooling to 950 °C. Rhyolitic magmas are stored at 200–300 MPa (i.e. ~7–11 km below the summit), 750 °C, NNO +2, and contain ~6–8 wt% H2O dissolved in a nearly aphyric melt (
Published: 2018
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33. Chronic Intake of Commercial Sweeteners Induces Changes in Feeding Behavior and Signaling Pathways Related to the Control of Appetite in BALB/c Mice

Author: José Antonio Estrada, Alberto A. Barrios-Correa, Rubén López-Santiago, Martin Olivier, Irazú Contreras, and Caroline Martel
Subjects: Male, STAT3 Transcription Factor, 0301 basic medicine, medicine.medical_specialty, Sucralose, Article Subject, media_common.quotation_subject, lcsh:Medicine, Biology, General Biochemistry, Genetics and Molecular Biology, Stat3 Signaling Pathway, BALB/c, Mice, 03 medical and health sciences, chemistry.chemical_compound, Weight loss, Internal medicine, medicine, Animals, 0501 psychology and cognitive sciences, 050102 behavioral science & comparative psychology, SOCS3, Protein kinase B, media_common, Mice, Inbred BALB C, General Immunology and Microbiology, lcsh:R, 05 social sciences, Brain, Appetite, Feeding Behavior, General Medicine, Janus Kinase 2, biology.organism_classification, 030104 developmental biology, Endocrinology, Gene Expression Regulation, chemistry, Suppressor of Cytokine Signaling 3 Protein, Sweetening Agents, Receptors, Leptin, Female, medicine.symptom, Proto-Oncogene Proteins c-akt, Weight gain, Research Article, Signal Transduction
Abstract: Nonnutritive sweetener use is a common practice worldwide. Although considered safe for human consumption, accumulating evidence suggests these compounds may affect metabolic homeostasis; however, there is no consensus on the role of frequent sweetener intake in appetite and weight loss. We sought to determine whether frequent intake of commercial sweeteners induces changes in the JAK2/STAT3 signaling pathway in the brain of mice, as it is involved in the regulation of appetite and body composition. We supplemented adult BALB/c mice with sucrose, steviol glycosides (SG), or sucralose, daily, for 6 weeks. After supplementation, we evaluated body composition and expression of total and phosphorylated JAK2, STAT3, and Akt, as well as SOCS3 and ObRb, in brain tissue. Our results show that frequent intake of commercial SG decreases energy intake, adiposity, and weight gain in male animals, while increasing the expression of pJAK2 and pSTAT3 in the brain, whereas sucralose increases weight gain and pJAK2 expression in females. Our results suggest that chronic intake of commercial sweeteners elicits changes in signaling pathways that have been related to the control of appetite and energy balance in vivo, which may have relevant consequences for the nutritional state and long term health of the organism.
Published: 2018
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34. Revised chronostratigraphy of recurrent ignimbritic eruptions in Dominica (Lesser Antilles arc): Implications on the behavior of the magma plumbing system

Author: Clara Solaro, Georges Boudon, Caroline Martel, Hélène Balcone-Boissard, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Pétrologie, géochimie, minéralogie magmatiques (PGM2), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), INSU-Aléas, Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC)
Subjects: 010504 meteorology & atmospheric sciences, Lithology, Outcrop, 14C dating, 010502 geochemistry & geophysics, 01 natural sciences, Paleontology, [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry, Geochemistry and Petrology, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Chronostratigraphy, Tephra, geochemistry, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Trace element, stratigraphy, lithology, Geophysics, Stratigraphy, Volcano, 13. Climate action, Magma, ignimbrites, Dominica, Geology
Abstract: International audience; Ignimbritic eruptions represent catastrophic events due to the magma volume involved and the related consequences on Earth's environment in relation with the released gases and the tephra dispersal. Dominica has been recognized as hosting one of the major ignimbritic eruptions of the last 200 ky in the Lesser Antilles arc, called the Roseau Tuff. But more recent works have evidenced several pumiceous events instead of a single large one. Here we propose a revised chronostratigraphy of the explosive activity that occurred in the last tens of thousands years based on three field trips, new 14C ages, detailed lithological and geochemical investigations, in particular a precise characterization of trace element glass chemistry. This eruptive history reconstruction is mainly based on outcrops along the coast and in the valley, since the luxury vegetation in the center of the island mostly precludes sections close to the central volcanic centers. We thus confirm that the Roseau event has been overestimated and that we may recognize five main ignimbritic events: Grande Savane, Layou (~ 51 ka), Grand Bay, Roseau (~ 33 ka), Grand Fond (~ 24 ka). We discuss the possible volcanic center at their origin, in addition to correlations with some Plinian events of lower magnitude that were identified in the Roseau valley and in the southern part of Dominica. This study may help to better constrain the eruptive history of the most active volcanic island of the Lesser Antilles arc, which has important implications on hazard mitigation.
Published: 2017
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35. Petrological and experimental constraints on magma storage for large pumiceous eruptions in Dominica island (Lesser Antilles)

Author: Michel Pichavant, Caroline Martel, Georges Boudon, Hélène Balcone-Boissard, Clara Solaro, Rémi Champallier, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), French INSU Action Incitative, European Project: 282759,EC:FP7:ENV,FP7-ENV-2011,VUELCO(2011), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Ignimbrite, Storage conditions, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Geochemistry, Silicic, Pyroclastic rock, 010502 geochemistry & geophysics, 01 natural sciences, Volcano, [SDU]Sciences of the Universe [physics], 13. Climate action, Geochemistry and Petrology, Pumice, Rhyolite, Phenocryst, Caldera, Dominica, Dacite, Phase equilibria, Martinique, Geology, 0105 earth and related environmental sciences
Abstract: International audience; The general question of the generation of large-volume silicic eruptions is here addressed through the experimental determination of the storage conditions of the primary magmas that generated ignimbritic eruptions at Dominica Island (Lesser Antilles) during the 24–51 ka period of time. The basal plinian fallouts and pumice pyroclastic flows from the large-volume (~ 5 km3 DRE) events of Layou, Roseau and Grand Fond were investigated, together with the smaller ignimbritic eruptions of Grand Bay and Grande Savane. All samples are dacitic (63–66 wt% SiO2) and contain ~ 30 vol% phenocrysts of plagioclase (~ 21 vol%), orthopyroxene (~ 5 vol%) and Fe-Ti oxides (
Published: 2019
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36. Exploitation of the Leishmania exosomal pathway by Leishmania RNA virus 1

Author: Aude Zimmermann, Visnu Chaparro, Caroline Martel, Alonso da Silva Lira Filho, Maritza Jaramillo, Vanessa D. Atayde, Martin Olivier, McGill University = Université McGill [Montréal, Canada], McGill University Health Center [Montreal] (MUHC), Institut Armand Frappier (INRS-IAF), Institut National de la Recherche Scientifique [Québec] (INRS)-Réseau International des Instituts Pasteur (RIIP), and This work is supported by grants from the Canadian Institute of Health Research to M.O. A.d.S.L.F. is a recipient of a Brazilian CNPq Science without Borders studentship award.
Subjects: Microbiology (medical), 0303 health sciences, biology, 030306 microbiology, Immunology, RNA, RNA virus, Cell Biology, Leishmania, biology.organism_classification, Applied Microbiology and Biotechnology, Microbiology, Exosome, Virology, Virus, Microvesicles, 03 medical and health sciences, RNA silencing, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Viral envelope, Genetics, 030304 developmental biology
Abstract: A Publisher Correction to this article was published on 26 February 2019; International audience; Leishmania are ancient eukaryotes that have retained the exosome pathway through evolution. Leishmania RNA virus 1 (LRV1)-infected Leishmania species are associated with a particularly aggressive mucocutaneous disease triggered in response to the double-stranded RNA (dsRNA) virus. However, it is unclear how LRV1 is exposed to the mammalian host cells. In higher eukaryotes, some viruses are known to utilize the host exosome pathway for their formation and cell-to-cell spread. As a result, exosomes derived from infected cells contain viral material or particles. Herein, we investigated whether LRV1 exploits the Leishmania exosome pathway to reach the extracellular environment. Biochemical and electron microscopy analyses of exosomes derived from LRV1-infected Leishmania revealed that most dsRNA LRV1 co-fractionated with exosomes, and that a portion of viral particles was surrounded by these vesicles. Transfer assays of LRV1-containing exosome preparations showed that a significant amount of parasites were rapidly and transiently infected by LRV1. Remarkably, these freshly infected parasites generated more severe lesions in mice than non-infected ones. Moreover, mice co-infected with parasites and LRV1-containing exosomes also developed a more severe disease. Overall, this work provides evidence that Leishmania exosomes function as viral envelopes, thereby facilitating LRV1 transmission and increasing infectivity in the mammalian host.
Published: 2019
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37. The intermediate step in fractionation trends of mildly alkaline volcanic suites: An experimental insight from the Pavin trachyandesite (Massif Central, France)

Author: Caroline Martel, Jean-Louis Bourdier, Morgane Rondet, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), ANR-11-EQPX-0036,PLANEX,Planète Expérimentation: simulation et analyse in-situ en conditions extrêmes(2011), and ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010)
Subjects: Pavin, 010504 meteorology & atmospheric sciences, Geochemistry, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Impact crater, Pumice, experimental petrology, 0105 earth and related environmental sciences, Global and Planetary Change, geography, geography.geographical_feature_category, Fragmentation (computing), Massif, differentiation, trachyandesite, Volcano, [SDU]Sciences of the Universe [physics], Clastic rock, Magma, engineering, General Earth and Planetary Sciences, Geology, Biotite, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; We examined magma storage conditions and eruptive dynamics for the trachyandesite (~58 wt% SiO2, 9–10 wt% alkalis) of the Pavin monogenetic volcano, a maar-like explosive crater belonging to a small group of youngest volcanoes in the Massif Central. By confronting the natural samples to experimental products, we constrained pre-eruptive conditions around 950–975 °C, 150–200 MPa (~5.5–7.0 km in depth), NNO+1.5, and 4.5–5.5 wt% melt H2O. There is petrological evidence of magma crystallization in the conduit up to shallow levels (~50 MPa; 2 km in depth) before fragmentation into pumice clasts in the last kilometre of ascent. The experiments highlight the role of biotite and of crystallization pressure in defining separate compositional trends of residual liquids, i.e. alkaline (trachytes) versus sub-alkaline (dacite-rhyolite).
Published: 2019
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38. Melt inclusions track melt evolution and degassing of Etnean magmas in the last 15 ka

Author: Andrea Luca Rizzo, Giada Iacono-Marziano, Marcello Liotta, Antonio Paonita, Michel Pichavant, Silvio G. Rotolo, Emanuela Gennaro, Caroline Martel, Gennaro, Emanuela, Iacono-Marziano, Giada, Paonita, Antonio, Rotolo, Silvio G., Martel, Caroline, Rizzo, Andrea L., Pichavant, Michel, Liotta, Marcello, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Dipartimento DiSTeM, Università di Palermo, Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Palermo (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Instituto Nationale di Geofisica e Vulcanologia (INGV), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), Gennaro, E, Iacono-Marziano, G, Paonita, A, Rotolo, S, Martel, C, Rizzo, A, Pichavant, M, and Liotta, M
Subjects: 010504 meteorology & atmospheric sciences, Geochemistry, Volatile content, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, Mantle (geology), Mineral redox buffer, Degassing, Geochemistry and Petrology, Silicate melt inclusion, Plagioclase, 0105 earth and related environmental sciences, Melt inclusions, Fractional crystallization (geology), Olivine, Spinel, Melt differentiation, Geology, Etna Silicate melt inclusions Volatile contents Melt differentiation Degassing, 13. Climate action, [SDU]Sciences of the Universe [physics], engineering, Phenocryst, Etna
Abstract: We present major elements compositions and volatiles contents of olivine-hosted melt inclusions from Etna volcano (Italy), which extend the existing database with the aim of interpreting the chemical variability of Etnean magmas over the last 15 ka. Olivine phenocrysts were selected from the most primitive Fall Stratified (FS) eruptive products of picritic composition (Mg# = 67–70, Fo 89–91 ), the Mt. Spagnolo eccentric lavas (Mg# = 52–64, Fo 82–88 ) and among the more recent 2002–2013 eruptive products (Mg# = 33–53, Fo 68–83 ). Crystal fractionation and degassing processes were modeled at temperatures of 1050–1300 °C, pressures
Published: 2019
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39. Rheology of crystal-bearing natural magmas: Torsional deformation experiments at 800 °C and 100 MPa

Author: Caroline Martel, Shingo Takeuchi, Rémi Champallier, Alexandra R. L. Kushnir, Satoshi Okumura, Quentin Thibault, Department of Earth and Planetary Materials Science [Sendai], Tohoku University [Sendai], Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Geosphere Sciences, Civil Engineering Research Laboratory, Civil Engineering Research Laboratory, and This study was carried out during the visit of SO to the deformation laboratory of ISTO, University of Orleans, and supported by the Leading Young Researcher Overseas Visit Program of Tohoku University and Grants-in-aid for Scientific Research in Japan (No. 15H03714). Postgraduate Scholarship-Doctoral (CGS D3) provided by the Natural Sciences and Engineering Research Council of Canada (NSERC) (number CGSD3-444207-2013)
Subjects: 010504 meteorology & atmospheric sciences, Magma rheology, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Mineralogy, Deformation (meteorology), 010502 geochemistry & geophysics, 01 natural sciences, Viscosity, Crystallinity, Rheology, Geochemistry and Petrology, High PT deformation experiment, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Petrology, 0105 earth and related environmental sciences, geography, geography.geographical_feature_category, Apparent viscosity, Bubble- and crystal-bearing magma, Volcanic rock, Geophysics, Volcano, [SDU]Sciences of the Universe [physics], 13. Climate action, Magma, Geology
Abstract: International audience; Rheological behavior of crystal-bearing magma is a controlling factor of magma flow dynamics and hence the style of volcanic eruptions. In this study, we performed torsional deformation experiments to determine the viscosity of crystal-bearing rhyolitic and dacitic magmas. The experiments were conducted at a temperature of 800 °C and under confining and pore fluid pressures of 100 and 80 MPa, respectively, by using an internally heated gas-medium deformation apparatus. To simulate the rheology of natural magma, we deformed volcanic rocks with 16 and 45 vol% crystallinities and < 4 vol% gas bubbles. These rocks have different crystal and bubble shape and size, which appear to influence magma rheology. By using the mechanical data obtained, we calculated flow indices and viscosities for these magmas. For magma with 16 vol% crystallinity, the flow index showed good agreement with previous data obtained from experiments on synthetic magma analogues and model predictions. In contrast, the flow index was smaller than those obtained from previous experiments and model predictions at 45 vol% crystallinity, which may be explained by considering that natural magma contains crystals with different shapes and sizes. We also found that the apparent viscosity of the magma increased when sample-scale fractures were observed in run products. This means that the heterogeneity of natural magma causes locally stiff regions within the sample owing to crystal interaction.
Published: 2016
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40. Leishmania exosomes and other virulence factors: Impact on innate immune response and macrophage functions

Author: Kasra Hassani, Martin Olivier, Andrezza Raposo Borges, Alonso da Silva Lira Filho, Caroline Martel, Vanessa D. Atayde, and Anupam Adhikari
Subjects: 0301 basic medicine, Virulence Factors, Immunology, Virulence, Biology, Exosomes, Exosome, Phagolysosome, Host-Parasite Interactions, Microbiology, 03 medical and health sciences, Immune system, parasitic diseases, Animals, Humans, Macrophage, Leishmaniasis, Leishmania, Innate immune system, 030102 biochemistry & molecular biology, Macrophages, Metalloendopeptidases, biology.organism_classification, Immunity, Innate, Microvesicles, 030104 developmental biology
Abstract: Leishmania parasites are the causative agents of the leishmaniases, a collection of vector-borne diseases that range from simple cutaneous to fatal visceral forms. Employing potent immune modulation mechanisms, Leishmania is able to render the host macrophage inactive and persist inside its phagolysosome. In the last few years, the role of exosomes in Leishmania-host interactions has been increasingly investigated. For instance, it was reported that Leishmania exosome release is augmented following temperature shift, a condition mimicking parasite’s entry into its mammalian host. Leishmania exosomes were found to strongly affect macrophage cell signaling and functions, similarly to whole parasites. Importantly, these vesicles were shown to be pro-inflammatory, capable to recruit neutrophils at their inoculation site exacerbating the pathology. In this review, we provide the most recent insights on the role of exosomes and other virulence factors, especially the surface protease GP63, in Leishmania-host interactions, deepening our knowledge on leishmaniasis and paving the way for the development of new therapeutics.
Published: 2016
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41. Deep pre-eruptive storage of silicic magmas feeding Plinian and dome-forming eruptions of central and northern Dominica (Lesser Antilles) inferred from volatile contents of melt inclusions

Author: Caroline Martel, Richard A. Brooker, H. Balcone-Boissard, Etienne Deloule, Clara Solaro, Jon D Blundy, Vladimir Matjuschkin, Georges Boudon, Institut des Sciences de la Terre de Paris (iSTeP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), School of Earth Sciences [Bristol], University of Bristol [Bristol], Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut für Geowissenschaften, J.W. Goethe University Frankfurt, Goethe-Universität Frankfurt am Main, CNRS-INSU TelluS-ALEAS, European Project: 282759,EC:FP7:ENV,FP7-ENV-2011,VUELCO(2011), Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Volatiles, Dominica, Melt inclusion, 010504 meteorology & atmospheric sciences, Andesite, Geochemistry, Silicic, engineering.material, 010502 geochemistry & geophysics, Dacite, 01 natural sciences, Arc magma, Geophysics, 13. Climate action, Geochemistry and Petrology, [SDU]Sciences of the Universe [physics], Magma, engineering, Lesser Antilles arc, Plagioclase, Mafic, Inclusion (mineral), Geology, 0105 earth and related environmental sciences, Melt inclusions
Abstract: International audience; Volatiles contribute to magma ascent through the sub-volcanic plumbing system. Here, we investigate melt inclusion compositions in terms of major and trace elements, as well as volatiles (H2O, CO2, SO2, F, Cl, Br, S) for Quaternary Plinian and dome-forming dacite and andesite eruptions in the central and the northern part of Dominica (Lesser Antilles arc). Melt inclusions, hosted in orthopyroxene, clinopyroxene and plagioclase are consistently rhyolitic. Post-entrapment crystallisation effects are limited, and negligible in orthopyroxene-hosted inclusions. Melt inclusions are among the most water-rich yet recorded (≤ 8 wt% H2O). CO2 contents are generally low (< 650 ppm), although in general the highest pressure melt inclusion contain the highest CO2. Some low-pressure (< 3 kbars) inclusions have elevated CO2 (up to 1100–1150 ppm), suggestive of fluxing of shallow magmas with CO2-rich fluids. CO2-trace element systematics indicate that melts were volatile-saturated at the time of entrapment and can be used for volatile-saturation barometry. The calculated pressure range (0.8–7.5 kbars) indicates that magmas originate from a vertically-extensive (3–27 km depth) storage zone within the crust that may extend to the sub-Dominica Moho (28 km). The vertically-extensive crustal system is consistent with mush models for sub-volcanic arc crust wherein mantle-derived mafic magmas undergo differentiation over a range of crustal depths. The other volatile range of composition for melt inclusions from the central part is F (75–557 ppm), Cl (1525–3137 ppm), Br (6.1–15.4 ppm) and SO2 (< 140 ppm), and for the northern part it’s F (92–798 ppm), Cl (1506–4428 ppm), Br (not determined) and SO2 (< 569; one value at 1015 ppm). All MIs, regardless of provenance, describe the same Cl/F correlation (8.3 ± 2.7), indicating that the magma source at depth is similar. The high H2O content of Dominica magmas has implications for hazard assessment.
Published: 2018
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42. Seismic imaging and petrology explain highly explosive eruptions of Merapi Volcano, Indonesia

Author: Antoine Laurin, Ahmad Ali Fahmi, Saskia Erdmann, Phil R. Cummins, Caroline Martel, Andri Dian Nugraha, Sri Widiyantoro, Agus Budi-Santoso, Mohamad Ramdhan, Jean-Philippe Métaxian, Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Bandung Institute of Technology, University of Indonesia, Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Center for Volcanology and Geological Hazard Mitigation, data were acquired using instruments belonging to the French national pool of portable seismic stations RESIF-SISMOB (CNRS-INSU)., ANR-12-BS06-0012,DOMERAPI,Dynamique d'un volcan d'arc à dômes de lave, le Merapi (Indonésie) : du réservoir magmatique aux processus éruptifs(2012), Institut Teknologi Bandung (ITB), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC)
Subjects: Moho Depth, 010504 meteorology & atmospheric sciences, Geophysical imaging, Science, 010502 geochemistry & geophysics, 01 natural sciences, Arrival time, Article, Mantle (geology), Petrology, Sea level, 0105 earth and related environmental sciences, geography, Magma Reservoir, Multidisciplinary, geography.geographical_feature_category, Explosive eruption, Magma Plumbing System, Merapi, Hazard potential, Merapi Volcano, Volcano, [SDU]Sciences of the Universe [physics], 13. Climate action, Seismic tomography, Medicine, Geology
Abstract: Our seismic tomographic images characterize, for the first time, spatial and volumetric details of the subvertical magma plumbing system of Merapi Volcano. We present P- and S-wave arrival time data, which were collected in a dense seismic network, known as DOMERAPI, installed around the volcano for 18 months. The P- and S-wave arrival time data with similar path coverage reveal a high Vp/Vs structure extending from a depth of ≥20 km below mean sea level (MSL) up to the summit of the volcano. Combined with results of petrological studies, our seismic tomography data allow us to propose: (1) the existence of a shallow zone of intense fluid percolation, directly below the summit of the volcano; (2) a main, pre-eruptive magma reservoir at ≥ 10 to 20 km below MSL that is orders of magnitude larger than erupted magma volumes; (3) a deep magma reservoir at MOHO depth which supplies the main reservoir; and (4) an extensive, subvertical fluid-magma-transfer zone from the mantle to the surface. Such high-resolution spatial constraints on the volcano plumbing system as shown are an important advance in our ability to forecast and to mitigate the hazard potential of Merapi’s future eruptions.
Published: 2018
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43. Exploitation of the Leishmania exosomal pathway by Leishmania RNA virus 1

Author: Vanessa Diniz, Atayde, Alonso, da Silva Lira Filho, Visnu, Chaparro, Aude, Zimmermann, Caroline, Martel, Maritza, Jaramillo, and Martin, Olivier
Subjects: Leishmania, Mice, Mice, Inbred BALB C, Virulence, Leishmaniavirus, Animals, Humans, Female, Exosomes, Leishmaniasis
Abstract: Leishmania are ancient eukaryotes that have retained the exosome pathway through evolution. Leishmania RNA virus 1 (LRV1)-infected Leishmania species are associated with a particularly aggressive mucocutaneous disease triggered in response to the double-stranded RNA (dsRNA) virus. However, it is unclear how LRV1 is exposed to the mammalian host cells. In higher eukaryotes, some viruses are known to utilize the host exosome pathway for their formation and cell-to-cell spread. As a result, exosomes derived from infected cells contain viral material or particles. Herein, we investigated whether LRV1 exploits the Leishmania exosome pathway to reach the extracellular environment. Biochemical and electron microscopy analyses of exosomes derived from LRV1-infected Leishmania revealed that most dsRNA LRV1 co-fractionated with exosomes, and that a portion of viral particles was surrounded by these vesicles. Transfer assays of LRV1-containing exosome preparations showed that a significant amount of parasites were rapidly and transiently infected by LRV1. Remarkably, these freshly infected parasites generated more severe lesions in mice than non-infected ones. Moreover, mice co-infected with parasites and LRV1-containing exosomes also developed a more severe disease. Overall, this work provides evidence that Leishmania exosomes function as viral envelopes, thereby facilitating LRV1 transmission and increasing infectivity in the mammalian host.
Published: 2018

44. In situ confirmation of permeability development in shearing bubble-bearing melts and implications for volcanic outgassing

Author: Rémi Champallier, Caroline Martel, Alexandra R. L. Kushnir, Laurent Arbaret, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), ARLK was provided by a Postgraduate Scholarship-Doctoral (CGSD3-444207-2013) provided by the Natural Sciences and Engineering Research Council of Canada (NSERC), and ANR-12-BS06-0012,DOMERAPI,Dynamique d'un volcan d'arc à dômes de lave, le Merapi (Indonésie) : du réservoir magmatique aux processus éruptifs(2012)
Subjects: 010504 meteorology & atmospheric sciences, Bubble, 010502 geochemistry & geophysics, 01 natural sciences, Fracture propagation, Electrical conduit, Geochemistry and Petrology, Earth and Planetary Sciences (miscellaneous), Shear stress, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Echelon formation, Petrology, 0105 earth and related environmental sciences, Shearing (physics), geography, geography.geographical_feature_category, magma, torsion, Geophysics, experiments, Outgassing, Mode I fractures, Volcano, Space and Planetary Science, outgassing, Geology
Abstract: International audience; The ferocity of volcanic eruptions – their penchant for either effusive or explosive behaviour – is to a large extent a matter of the ease with which volatiles are able to escape the volcanic system. Of particular importance are the mechanisms by which permeable networks within magma are fabricated and how they permit gas escape, thereby diffusing possibly calamitous explosions. Here, we present a series of experiments that confirms sample-scale fracture propagation and permeability development during shearing viscous flow of initially impermeable, bubble-bearing (2×10−4 s−1). At moderate shear strain rates (2×10−4 s−13) via en échelon Mode I fractures produced by repeated fracture events. At high shear strain rates (γ˙>4.5×10−4 s−1), permeability develops shortly after the onset of inelastic deformation and is, again, established through a series of en échelon Mode I fractures. Critically, strain is not immediately localized on Mode I fractures, making them long-lived and efficient outgassing channels that are ideally oriented for directing volatiles from the central conduit upward and outward toward the conduit rim. Indeed, Mode I fracture arrays may prove necessary for dissipating gas overpressures in the central regions of the magma column, which are considered difficult to outgas. These experiments highlight mechanisms that are likely active along conduit margins and constrain previously postulated processes under truly applicable conditions.
Published: 2017
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45. Experimental Simulations of Magma Storage and Ascent

Author: Jon D Blundy, Bruno Scaillet, Caroline Martel, Michael Pichavant, Joan Andújar, Richard A. Brooker, Magma - UMR7327, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), School of Earth Sciences [Bristol], University of Bristol [Bristol], Joachim Gottsmann, Jürgen Neuberg, Bettina Scheu, European Project: 282759,EC:FP7:ENV,FP7-ENV-2011,VUELCO(2011), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)
Subjects: Vulcanian eruption, 010504 meteorology & atmospheric sciences, Pyroclastic rock, Replicate, 010502 geochemistry & geophysics, Key issues, 01 natural sciences, 13. Climate action, Magma, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, Petrology, Geology, 0105 earth and related environmental sciences, Melt inclusions
Abstract: International audience; One of the key issues in utilizing precursor signals of volcanic eruption is to reliably interpret geophysical and geochemical data in terms of magma movement towards the surface. An important first step is to identify where the magma is stored prior to ascent. This can be studied through phase-equilibrium experiments designed to replicate the phase assemblage and compositions of natural pyroclasts or by measuring volatiles in melt inclusions from previous eruptions. The second crucial step is to characterize the magmatic conditions and processes that will guide the eruption style. This may be addressed through controlled dynamic decompression or deformation experiments to examine the different rates that govern the kinetics of syn-eruptive degassing, crystallization, and strain. Comparing the compositional and textural characteristics of these experimental products with the natural samples can be used to retrieve magma ascent conditions. These experimental simulations allow interpretation of direct observations and in situ measurements of syn-eruptive processes leading to more accurate forecasting of future eruptive scenarios.
Published: 2017
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46. Structure of the plumbing system at Tungurahua volcano, Ecuador : insights from phase equilibrium experiments on july-august 2006 eruption products

Author: Michel Pichavant, Bruno Scaillet, Pablo Samaniego, Joan Andújar, Indira Molina, Caroline Martel, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Magma - UMR7327, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Instituto Geofísico, Escuela Politécnica Nacional, Escuela Politécnica Nacional (EPN), CNRS-INSU : ALEAS : The change in eruptive dynamics on arc volcanoes: the role of magma composition and structure of the plumbing system exemplified at Tungurahua volcano, Ecuador, ANR-11-EQPX-0036,PLANEX,Planète Expérimentation: simulation et analyse in-situ en conditions extrêmes(2011), ANR-10-LABX-0100,VOLTAIRE,Geofluids and Volatil elements – Earth, Atmosphere, Interfaces – Resources and Environment(2010), European Project: 282759,EC:FP7:ENV,FP7-ENV-2011,VUELCO(2011), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet [Saint-Étienne] (UJM)-Institut de Recherche pour le Développement et la société-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut national des sciences de l'Univers (INSU - CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement et la société-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Université Jean Monnet [Saint-Étienne] (UJM)
Subjects: 010504 meteorology & atmospheric sciences, Geochemistry, plumbing system, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, 010502 geochemistry & geophysics, 01 natural sciences, Geochemistry and Petrology, Mineral redox buffer, pre-eruptive conditions, experimental petrology, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, basaltic andesite, phase equilibrium, 0105 earth and related environmental sciences, magnesian, geography, geography.geographical_feature_category, Phase equilibrium, andesite, Andesite, Tungurahua, Overpressure, Geophysics, Volcano, 13. Climate action, Magma, Phenocryst, adakite, Mafic, Geology
Abstract: Understanding the plumbing system structure below volcanoes and the storage conditions (temperature, pressure, volatile content and oxygen fugacity) of erupted magmas is of paramount importance for eruption forecasting and understanding of the factors controlling eruptive dynamics. Phase equilibria experiments have been performed on a Tungurahua andesite (Ecuador) to shed light on the magmatic conditions that led to the July-August 2006 eruptions and the parameters that controlled the eruptive dynamics. Crystallization experiments were performed on a representative August 2006 mafic andesite product between 950 and 1025A degrees C, at 100, 200 and 400 MPa and NNO + 1 and NNO + 2 (where NNO is nickel-nickel oxide buffer), and water mole fractions in the fluid (XH2O) from 0 center dot 3 to 1 (water-saturation). Comparison of the natural phenocryst assemblage, proportions and phenocryst compositions with our experimental data indicates that the natural andesite experienced two levels of ponding prior to the eruption. During the first step, the magma was stored at 400 MPa (15-16 km), 1000A degrees C, and contained c. 6 wt % dissolved H2O. In the second step, the magma rose to a confining pressure of 200 MPa (8-10 km), where subsequent cooling (to 975A degrees C) and water-degassing of the magma led to the crystallization of reversely zoned rims on pre-existing phenocrysts. The combination of these processes induced oxidation of the system and overpressure of the reservoir, triggering the July 2006 eruption. The injection of a new, hot, volatile-rich andesitic magma from 15-16 km into the 200 MPa reservoir shortly before the eruption was responsible for the August 2006 explosive event. Our results highlight the complexity of the Tungurahua plumbing system in which different magmatic reservoirs can coexist and interact in time and are the main controlling factors of the eruptive dynamics.
Published: 2017
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47. Characteristic Textures of Recrystallized, Peritectic, and Primary Magmatic Olivine in Experimental Samples and Natural Volcanic Rocks

Author: Anita Cadoux, Saskia Erdmann, Bruno Scaillet, Caroline Martel, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)
Subjects: Basalt, geography, Recrystallization (geology), geography.geographical_feature_category, Olivine, 010504 meteorology & atmospheric sciences, Geochemistry, Mineralogy, engineering.material, 010502 geochemistry & geophysics, 01 natural sciences, law.invention, Volcanic rock, Geophysics, Geochemistry and Petrology, law, Ultramafic rock, [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, engineering, Phenocryst, Grain boundary, Crystallization, Geology, 0105 earth and related environmental sciences
Abstract: International audience; Olivine textures are potentially important recorders of olivine origin and crystallization conditions. Primary magmatic and xenocrystic origins are commonly considered for olivine from ultramafic to intermediate magmas, while secondary olivine origins (i.e. crystals formed by recrystallization or peritectic reaction) are rarely considered in the interpretation of magmatic phenocrysts. The main aim of our study was to determine textures that are characteristic for secondary magmatic olivine and non-characteristic, or at least rare, for primary magmatic olivine. To characterize the textures of the different olivine types, we review previous experimental work and present new textural data for olivine from four melanorite melting and eight basalt crystallization experiments. We (i) qualitatively characterize olivine textures using transmitted light and back-scattered electron microscopy; and (iii) semi-quantitatively characterize the 2D surface area of olivine branches and individual crystals, their 2D and calculated 3D shapes, and 2D grain boundary segment
Published: 2014
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48. Publisher Correction: Exploitation of the Leishmania exosomal pathway by Leishmania RNA virus 1

Author: Caroline Martel, Visnu Chaparro, Alonso da Silva Lira Filho, Vanessa D. Atayde, Aude Zimmermann, Maritza Jaramillo, Martin Olivier, McGill University = Université McGill [Montréal, Canada], McGill University Health Center [Montreal] (MUHC), Institut Armand Frappier (INRS-IAF), Institut National de la Recherche Scientifique [Québec] (INRS)-Réseau International des Instituts Pasteur (RIIP), and This work is supported by grants from the Canadian Institute of Health Research to M.O. A.d.S.L.F. is a recipient of a Brazilian CNPq Science without Borders studentship award.
Subjects: Microbiology (medical), viruses, health care facilities, manpower, and services, education, Immunology, RNA virus, Cell Biology, Biology, Leishmania, biology.organism_classification, Applied Microbiology and Biotechnology, Microbiology, Virology, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, parasitic diseases, Genetics, health care economics and organizations
Abstract: International audience; Erratum for : Exploitation of the Leishmania exosomal pathway by Leishmania RNA virus 1
Published: 2019
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49. Cysteine Peptidase B Regulates Leishmania mexicana Virulence through the Modulation of GP63 Expression

Author: W. Robert McMaster, Jeremy C. Mottram, Martin Olivier, Albert Descoteaux, Caroline Martel, Pierre-André Casgrain, Institut Armand Frappier (INRS-IAF), Institut National de la Recherche Scientifique [Québec] (INRS) - Réseau International des Instituts Pasteur - Institut Armand Frappier, Research Institute of the McGill University Health Centre, 1650 Cedar Avenue, Immunity and Infection Research Centre, Vancouver Coastal Health Research Institute, Centre for Immunology and Infection, University of York [York], This work was supported by Canadian Institutes of Health Research grants MOP-125990 to AD and MOP-12671 to MO and the MedicalResearch Council (MR/K019384) to JCM. The Centre for Host-Parasite Interactions is supported by the Fonds de Recherche du Québec - Nature etTechnologies (Regroupement Stratégique). The Wellcome Trust Centre for Molecular Parasitology issupported by core funding from the Wellcome Trust[104111]. The funders had no role in study design, Institut National de la Recherche Scientifique [Québec] (INRS)-Réseau International des Instituts Pasteur (RIIP), McGill University Health Center [Montreal] (MUHC), Vancouver Coastal Health Research Institute (VCH), and University of York [York, UK]
Subjects: 0301 basic medicine, Life Cycles, [SDV]Life Sciences [q-bio], Endocytic cycle, Mutant, Leishmania mexicana, Protozoan Proteins, Vacuole, Pathogenesis, Protozoology, Pathology and Laboratory Medicine, White Blood Cells, Mice, Animal Cells, Medicine and Health Sciences, Leishmania major, Biology (General), Protozoans, Leishmania, [SDV.MP.VIR] Life Sciences [q-bio]/Microbiology and Parasitology/Virology, Mice, Inbred BALB C, Leishmania Major, Microscopy, Confocal, biology, Virulence, Reverse Transcriptase Polymerase Chain Reaction, Metalloendopeptidases, Flow Cytometry, Cell biology, [SDV] Life Sciences [q-bio], surgical procedures, operative, [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology, Host-Pathogen Interactions, Protozoan Life Cycles, Cellular Types, Pathogens, [SDV.MP.PAR] Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Research Article, circulatory and respiratory physiology, Virulence Factors, QH301-705.5, Immune Cells, Immunology, Blotting, Western, Leishmaniasis, Cutaneous, Phagolysosome, Microbiology, Parasite Replication, 03 medical and health sciences, Virology, parasitic diseases, Genetics, Parasitic Diseases, Animals, [SDV.MP.PAR]Life Sciences [q-bio]/Microbiology and Parasitology/Parasitology, Cysteine, Molecular Biology, Blood Cells, 030102 biochemistry & molecular biology, Macrophages, Promastigotes, Organisms, Biology and Life Sciences, Cell Biology, RC581-607, biology.organism_classification, Parasitic Protozoans, Disease Models, Animal, 030104 developmental biology, Gene Expression Regulation, Parasitology, Immunologic diseases. Allergy, Developmental Biology, Peptide Hydrolases
Abstract: Cysteine peptidases play a central role in the biology of Leishmania. In this work, we sought to further elucidate the mechanism(s) by which the cysteine peptidase CPB contributes to L. mexicana virulence and whether CPB participates in the formation of large communal parasitophorous vacuoles induced by these parasites. We initially examined the impact of L. mexicana infection on the trafficking of VAMP3 and VAMP8, two endocytic SNARE proteins associated with phagolysosome biogenesis and function. Using a CPB-deficient mutant, we found that both VAMP3 and VAMP8 were down-modulated in a CPB-dependent manner. We also discovered that expression of the virulence-associated GPI-anchored metalloprotease GP63 was inhibited in the absence of CPB. Expression of GP63 in the CPB-deficient mutant was sufficient to down-modulate VAMP3 and VAMP8. Similarly, episomal expression of GP63 enabled the CPB-deficient mutant to establish infection in macrophages, induce the formation of large communal parasitophorous vacuoles, and cause lesions in mice. These findings implicate CPB in the regulation of GP63 expression and provide evidence that both GP63 and CPB are key virulence factors in L. mexicana., Author Summary The parasite Leishmania mexicana expresses several cysteine peptidases of the papain family that are involved in processes such as virulence and evasion of host immune responses. The cysteine peptidase CPB is required for survival within macrophages and for lesion formation in susceptible mice. Upon their internalization by macrophages, parasites of the L. mexicana complex induce the formation of large communal parasitophorous vacuoles in which they replicate, and expansion of those large vacuoles correlates with the ability of the parasites to survive inside macrophages. Here, we found that CPB contributes to L. mexicana virulence (macrophage survival, formation and expansion of communal parasitophorous vacuoles, lesion formation in mice) through the regulation of the virulence factor GP63, a Leishmania zinc-metalloprotease that acts by cleaving key host cell proteins. This work thus elucidates a novel Leishmania virulence regulatory mechanism whereby CPB controls the expression of GP63.
Published: 2016
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50. Constraints from Phase Equilibrium Experiments on Pre-eruptive Storage Conditions in Mixed Magma Systems: a Case Study on Crystal-rich Basaltic Andesites from Mount Merapi, Indonesia

Author: Rémi Champallier, Michel Pichavant, Jean-Christophe Komorowski, Noer Cholik, Jean-Louis Bourdier, Saskia Erdmann, Caroline Martel, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut de Physique du Globe de Paris (IPGP), Centre National de la Recherche Scientifique (CNRS)-Université de La Réunion (UR)-Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Institut national des sciences de l'Univers (INSU - CNRS), BPPTK (Balai Penyelidikan dan Pengembangan Tekonologi Kegunungapian), Merapi Volcano Observatory – BPPTK, Yogyakarta, Indonesia, ANR-12-BS06-0012,DOMERAPI,Dynamique d'un volcan d'arc à dômes de lave, le Merapi (Indonésie) : du réservoir magmatique aux processus éruptifs(2012), ANR-09-RISK-0002,CASAVA,Compréhension et Analyse des Scénarios, Aléas, et risques Volcaniques aux Antilles ? Implications pour l?aide à la décision, la gestion de crise, et le développement raisonné(2009), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Geochemistry, 010502 geochemistry & geophysics, 01 natural sciences, crystal-rich, magma mixing, law.invention, Geochemistry and Petrology, law, Phase (matter), [SDU.STU.VO]Sciences of the Universe [physics]/Earth Sciences/Volcanology, H2O, Crystallization, 0105 earth and related environmental sciences, Basalt, geography, geography.geographical_feature_category, biology, experiment, Andesites, Merapi, Groundwater recharge, biology.organism_classification, Geophysics, volatiles, Volcano, 13. Climate action, Magma, Igneous differentiation, CO2, Geology
Abstract: International audience; Mount Merapi is one of Indonesia’s and the world’s most hazardous volcanoes. Existing constraints on the location and the crystallization conditions of its pre-eruptive magma reservoir based on mineral and glass thermobarometry and geophysical surveys are inconclusive, yet of immediate importance for future hazard mitigation. Here, we use two series of phase equilibrium experiments to quantify the conditions of pre-eruptive magma storage and magma recharge in Merapi’s upper-crustal reservoir: (1) to characterize crystallization at total equilibrium conditions; (2) to characterize crystallization at local equilibrium conditions between crystal rims and host melt. We demonstrate that this experimental approach can constrain pre-eruptive crystallization conditions and their variation in crystal-rich, mixed magma systems, such as that of Merapi, for which standard crystallization experiments and mineral thermobarometry fail. In agreement with geophysical estimates, we infer that Mount Merapi’s pre-eruptive reservoir partially crystallizes at ≥100–200 ± 75 MPa and thus at relatively shallow depths of c. ≥4·5 to ∼9 km. Magmas are stored at ≥925–950 ± 25°C with a melt H2O content of ∼3–4 wt % and a vapour phase with an XH2O [H2O/(H2O + CO2)] of ∼0·5–0·6 ± 0·1. Pre-eruptive recharge magmas, in contrast, have a temperature >950 to
Published: 2016
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