62 results on '"J. Guyon"'
Search Results
2. Japanese Hops (Humulus japonicus) Control and Management Strategies in Large River Floodplains
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Robert J. Cosgriff and Lyle J. Guyon
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geography ,geography.geographical_feature_category ,biology ,Floodplain ,Botany ,Forestry ,Plant Science ,biology.organism_classification ,Humulus japonicus - Abstract
Japanese hops (Humulus japonicus) is an invasive vine that establishes in open areas in riverine habitats and suppresses tree regeneration and native vegetation. This study evaluated the use of herbicides and tree plantings to control and manage Japanese hops on five Mississippi River islands over a four-year period. Herbicide treatments included a preemergent (sulfometuron methyl), a postemergent (glyphosate), and a combination of both. Tree plantings used containerized and bareroot American sycamore (Platanus occidentalis) and eastern cottonwood (Populus deltoides) trees. Japanese hops biomass was significantly lower in all herbicide treatments in 2012 and 2015, but the preemergent treatment was less effective than other treatments in 2012 and 2014. After two years, average survivorship of containerized trees was 20%–42%, whereas bareroot seedlings had near 100% mortality. Results indicate that postemergent treatments are effective for short-term control, but large floods reestablish Japanese hops in treated areas. Reforestation, if combined with herbicide treatments and active management, may be a promising approach in large river floodplains that experience frequent flooding, but low tree survivorship presents challenges to reforestation.
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- 2021
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3. Spatially explicit modelling of floodplain forest succession: interactions among flood inundation, forest successional processes, and other disturbances in the Upper Mississippi River floodplain, USA
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Nathan R. De Jager, Jason J. Rohweder, Timothy J. Fox, Molly Van Appledorn, Benjamin J. Vandermyde, Lyle J. Guyon, Robert J. Cosgriff, and Andrew R. Meier
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0106 biological sciences ,Hydrology ,geography ,geography.geographical_feature_category ,Floodplain ,Flood myth ,Forest dynamics ,010604 marine biology & hydrobiology ,Ecological Modeling ,Context (language use) ,Ecological succession ,010603 evolutionary biology ,01 natural sciences ,Disturbance (ecology) ,Abundance (ecology) ,Environmental science ,Riparian zone - Abstract
Simulation models are often used to identify hydrologic regimes suitable for different riparian or floodplain tree species. However, most existing models pay little attention to forest successional processes or other disturbances that may interact with the hydrologic regime of river systems to alter forest dynamics in space and time. In this study, we introduce a flood disturbance module to the LANDIS-II forest succession modelling framework to enable investigations into how inundation interacts with other disturbances and successional processes to alter floodplain forest cover and community dynamics. We illustrate the functionality of the model using a case study with multiple scenarios in the Upper Mississippi River floodplain, USA. We found that model predictions of total forest cover and the abundance of specific forest community types were generally related to uncertainty in the susceptibility of different species and age classes to inundation. By simulation year 100, increases or decreases in total forest cover and forest type distributions were roughly proportional to the initial differences in the susceptibility of species and age classes to inundation. The largest decrease in total forest cover was associated with a scenario that included disturbance by the emerald ash borer (Agrilus planipennis) and when using susceptibility parameters corresponding to the weakest flood tolerance. In contrast, changes in the composition of aboveground biomass were not sensitive to differences in susceptibility, and generally showed shifts toward later successional species with higher shade tolerance and longer lifespans for all scenarios. Our findings suggest that flood inundation interacts with other disturbances (e.g., insect outbreaks) and forest successional processes to alter forest abundance, distribution, and species composition in this system. Our modelling framework should allow for future studies that examine such interactions in other systems, and in the context of alternative hydrologic scenarios and other disturbance regimes.
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- 2019
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4. Characterization of a nanopipe dislocation in GaN by means of HR-EBSD and field dislocation mechanics analysis
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C. Ernould, V. Taupin, B. Beausir, J.J. Fundenberger, N. Maloufi, J. Guyon, and E. Bouzy
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science ,Condensed Matter Physics - Published
- 2022
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5. Influence of Ir Additions and Icosahedral Short Range Order (ISRO) on Nucleation and Growth Kinetics in Au-20.5Wt Pct Cu-4.5Wt PctAg Alloy
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J. Guyon, Michel Rappaz, Julien Zollinger, Bernard Rouat, S. Pillai, Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), Centre National de la Recherche Scientifique (CNRS)-Université de Lorraine (UL)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Ecole Polytechnique Fédérale de Lausanne (EPFL), and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies
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Materials science ,Morphology (linguistics) ,dendrites ,Icosahedral symmetry ,Spinodal decomposition ,Alloy ,0211 other engineering and technologies ,Nucleation ,02 engineering and technology ,crystal-enhanced nucleation ,system ,engineering.material ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,quasi-crystal ,Phase (matter) ,0103 physical sciences ,phase ,021102 mining & metallurgy ,010302 applied physics ,Metallurgy ,Metals and Alloys ,Quasicrystal ,morphologies ,Condensed Matter Physics ,al ,Crystallography ,Mechanics of Materials ,[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] ,engineering ,cr ,Electron backscatter diffraction - Abstract
Based on detailed EBSD analyses, Kurtuldu et al. (Acta Mater. 70:240–248, 2014) have explained the grain refinement of Au-12.5 wt pctCu-12.5 wt pctAg (yellow gold) by the addition of minute amounts of Ir in terms of “icosahedral quasicrystal (iQC)-mediated nucleation”, i.e., Ir induced the formation of Icosahedral short range order (ISRO) of atoms in the liquid, leading to the formation of iQC on which the fcc-phase forms. In the present contribution, we show that: (i) this mechanism is also responsible of the grain refinement in Au-20.5 wt pctCu-4.5 wt pctAg (pink gold) with Ir addition; (ii) ISRO also influences the morphology and growth kinetics of the fcc phase: at solidification rate of a few mm/s, $$\langle 100\rangle $$ dendrites are replaced by a cellular-type morphology growing along $$\langle 111\rangle $$ when 100 wt ppm of Ir is added to the melt; (iii) iQC-mediated nucleation is accompanied by a spinodal decomposition of the liquid, which is revealed at high cooling rate by the formation of Cu-rich particles or dendrites, some of them being also twinned, in parallel to iQC-mediated grain refinement and twin formation.
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- 2019
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6. Ecological characteristics of floodplain forest reference sites in the Upper Mississippi River System
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Lyle J. Guyon and Loretta L. Battaglia
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0106 biological sciences ,geography.geographical_feature_category ,biology ,Floodplain ,Ecology ,010604 marine biology & hydrobiology ,Biodiversity ,Species diversity ,Forestry ,Understory ,Management, Monitoring, Policy and Law ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Silver maple ,Forest restoration ,Geography ,Species richness ,Restoration ecology ,Nature and Landscape Conservation - Abstract
Historical and present day disturbances have contributed to long-term changes in the extent, composition, and structure of Upper Mississippi River System (UMRS) floodplain forests. Loss of forest habitat, low tree species diversity, a lack of successful regeneration in many areas, and continued declines in forest health over time are serious threats to this ecosystem. Floodplain forest restoration has therefore gained importance as a management goal throughout the UMRS. A key component of the restoration process is assessing the ecological characteristics of remnant, high quality reference sites to identify appropriate targets for forest restoration efforts. In this study, fourteen reference sites were located and established along a ∼1140 km longitudinal stretch of the Upper Mississippi River, lower Illinois River, lower Big Muddy River, and lower Cache River watershed. Biological and abiotic data were sampled from 1000 m2 permanent plots located at each study site. Overstory floodplain forest communities were generally dominated by silver maple (Acer saccharinum) and a variable combination of green ash (Fraxinus pennsylvanica), American elm (Ulmus americana), cottonwood (Populus deltoides), pin oak (Quercus palustris), and hackberry (Celtis occidentalis). Common understory trees capable of overstory recruitment included silver maple, green ash, American elm, and hackberry. Overstory species richness and diversity were generally high, but species richness and diversity in the understory layer were much lower, a trend that was most pronounced in the northernmost sites. In addition, the scarcity of mast producing and/or shade intolerant species in the understory was evident throughout the study, even at sites where they were present in the overstory. Herbaceous communities were notably variable between study sites. Despite the latitudinal gradient, ordination of the floodplain forest communities revealed substantial compositional overlap between sites. However, patterns in the ordination were significantly correlated with local variability in canopy cover, elevation, soil texture, and several hydrologic parameters. Species richness and diversity generally increased from north to south. Results suggest that regional differences and local characteristics such as microtopographic features should be considered when selecting target restoration conditions and evaluating the suitability of individual species for specific restoration projects.
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- 2018
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7. RECOVERIES OF HIGH SEAS TAGS AND TAG RELEASES FROM HIGH SEAS RESEARCH VESSEL SURVEYS IN 2017
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S Sato, E Akinicheva, A Bugaev, L Campbell, J Guyon, J Holmes, C H Jeon, J K Kim, C Neville, D Oxman, T Tojima, S Urawa, V Volobuev, A C Seitz, M Koval, and Koval, Maksim V.
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- 2018
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8. I. Présentation des sites
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M. Vidal, I. Barthélémy, J.-P. Cazes, Cl. Raynaud, P. Dupouey, S. Duchesne, F.-X. Ricaut, P. Murail, J. Guyon, Ch. Duhamel, M. Bessou, and A. Martin
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Les sites etudies appartiennent a deux regions du sud de la France : Midi-Pyrenees, avec cinq sites issus de trois departements, la Haute-Garonne (a Saint-Bertrand-de-Comminges et Venerque), le Gers (a L’Isle-Jourdain et Ordan-Larroque), et le Tarn (a Vindrac-Alayrac), mais aussi Languedoc-Roussillon, avec deux sites issus du departement de l’Herault (a Lunel-Viel) (fig. 1). La ville de Saint-Bertrand-de-Comminges est situee a pres de 110 km au sud-ouest de Toulouse, dans le piemont pyreneen....
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- 2016
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9. A simple technique using wooden stakes to estimate vertical patterns of interstitial oxygenation in the beds of rivers
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Andrew J. Boulton, Sébastien Lefebvre, J. Guyon, Pierre Marmonier, and Yannick R. Delettre
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Hydrology ,Ecology ,Sediment ,Hypoxia (environmental) ,Aquatic Science ,Silt ,Siltation ,Clogging ,chemistry.chemical_compound ,Nitrate ,chemistry ,Environmental science ,Subsurface flow ,Hydrobiology - Abstract
Silt and fine sediments from anthropogenic activities frequently clog river bed sediments, impairing vertical exchanges between stream and subsurface water. River managers need a simple technique to detect the extent of interstitial clogging and monitor the effectiveness of measures to reduce siltation. We evaluated the use of 30-cm long pine-wood stakes, inserted for 3-6 weeks in the sediments of four French rivers varying in interstitial clogging, to determine the association between changes in the colour of the wood and the adjacent interstitial conditions. There was a general association between depth to interstitial hypoxia and location of the colour change of the wooden stakes from brown to pale grey or black after 3-4 weeks. This change in colour also broadly matched interstitial contents of fine sediment, ammonium, and nitrate although the method could not reliably detect microscale zones of anoxia or short-term changes in dissolved oxygen. Thus, its effectiveness lies in its use as a cheap, simple, and broad-scale indicator for collecting long-term integrated data of interstitial oxygenation in stream sediments with minimal disruption of the gravel bed, and appears an ideal tool for river managers and salmonid fish biologists.
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- 2004
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10. From Lugdunum to Convenae: recent work on Saint-Bertrand-de-Comminges (Haute-Garonne)
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J.-L. Paillet, P. Aupert, F. Tassaux, C. Dieulafait, C. Petit, J.-M. Pailler, J. Guyon, M. Janon, J. Gallagher, D. Schaad, J.-L. Schenk, R. Sablayrolles, and G. Fabre
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Archeology ,Visual Arts and Performing Arts ,Work (electrical) ,media_common.quotation_subject ,SAINT ,Art ,Classics ,Humanities ,media_common - Published
- 1991
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11. Sonographic differentiation of enlarged hepatic arteries from dilated intrahepatic bile ducts
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J Guyon, FC Laing, RB Jeffrey, and VW Wing
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Male ,medicine.medical_specialty ,Cirrhosis ,medicine.diagnostic_test ,business.industry ,Intrahepatic bile ducts ,Computed tomography ,General Medicine ,Intrahepatic duct ,medicine.disease ,Diagnosis, Differential ,Bile Ducts, Intrahepatic ,Hepatic Artery ,Dilated intrahepatic bile ducts ,medicine ,Humans ,Portal hypertension ,Female ,Radiology, Nuclear Medicine and imaging ,Radiology ,Increased blood flow ,Tomography, X-Ray Computed ,business ,Dilatation, Pathologic ,Ultrasonography - Abstract
Identifying parallel tubular structures within the liver by sonography has been regarded as a sensitive and specific sign of intrahepatic duct dilatation. Eight cases are reported in which parallel tubes within the liver were shown not to represent dilated ducts on computed tomography, but rather enlarged hepatic arteries due to increased blood flow. All eight patients had a history of alcoholism and/or cirrhosis and had at least one ancillary sign of portal hypertension. The sonographic findings in these eight patients were compared with similar findings in 12 other patients who were subsequently found to have true intrahepatic bile duct dilatation. Sonographic features that were helpful in distinguishing these two groups are described.
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- 1985
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12. Generateur d'impulsions nanoseconde et circuit de mise en forme a transistors avalanche
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J. Guyon, A. Sarazin, and J.J. Samueli
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Physics ,business.industry ,Pulse generator ,Transistor ,General Medicine ,Nanosecond ,law.invention ,Amplitude ,law ,Avalanche transistor ,Rise time ,Optoelectronics ,business ,Pulse-width modulation ,Electronic circuit - Abstract
A pulse generator which operates at high continuous repetition rates and produces rectangular or exponential pulses is described. The circuit is all solid-state and uses avalanche transistor. At 5 Mc/s the pulse width is adjustable from 2 to 10 nanoseconds with a 0.5 nanoseconds rise time and 8 volt amplitude on 50 ohms. At 25 Mc/s exponential pulses are produced with 1 nanoseconds rise and 15 nanoseconds fall times.
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- 1964
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13. Light transit-time compensator for large scintillators
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J. Pigneret, M. Gouanere, and J. Guyon
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Physics ,Physics::Instrumentation and Detectors ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,General Medicine ,Scintillator ,Collimated light ,Pulse (physics) ,Crystal ,Full width at half maximum ,Optics ,Scintillation counter ,Optoelectronics ,Particle ,business ,Electronic circuit - Abstract
An electronic system has been constructed to minimize the timing incertitude due to the transit time of the light emitted in large plastic scintillators (7 dm 3 ). The system needs no adjustment and gives at its output a timing pulse which shifts by no more than ±120 ps for different points of interaction of the incident particle in the scintillator crystal. The time resolution obtained with 400 keV collimated rays is 1.1 ns (fwhm).
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- 1969
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14. Hands on stamps. France--Issue of 1979
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F J, Guyon
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Paris ,Humans ,History, 19th Century ,France ,Anatomy ,History, 20th Century ,Wrist ,Philately - Published
- 1982
15. CT demonstration of optic canal fractures
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Stuart R. Seiff, Michael Brant-Zawadzki, and Jeffrey J. Guyon
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Adult ,Male ,medicine.medical_specialty ,Optic canal ,Skull Fractures ,business.industry ,Sphenoid bone ,Vision Disorders ,General Medicine ,Skull ,medicine.anatomical_structure ,Concomitant ,Optic Nerve Injuries ,Sphenoid Bone ,medicine ,Optic nerve ,Foramen ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,Tomography ,business ,Tomography, X-Ray Computed ,Guarded prognosis - Abstract
Traumatic blindness is a well recognized entity with a guarded prognosis. Previous studies have variously reported the incidence of concomitant optic canal fractures and response to surgical therapy. With the advent of CT scanning, a new technique for study of these severely injured patients has become available. Over a period of 20 months, optic foramen fractures were demonstrated in 10 such patients using finely collimated, high-resolution CT scans. Fractures were easily classified by location, relation to the optic nerve assessed, and associated facial injuries imaged. The technique is easy, rapid, and superior to polytomography in this setting. Possible implications for therapy are discussed.
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- 1984
16. The concentration of Onchocerca volvulus microfilariae in skin snips taken over twenty-four hours
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P. D. Scheffel, B. O. L. Duke, J. Guyon, and P. J. Moore
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biology ,Carrier state ,030231 tropical medicine ,Skin snips ,Temperature ,Physiology ,Insect Bites and Stings ,biology.organism_classification ,Onchocerciasis ,Onchocerca volvulus ,Circadian Rhythm ,03 medical and health sciences ,0302 clinical medicine ,Infectious Diseases ,030225 pediatrics ,Nematode larvae ,Immunology ,Helminths ,Humans ,Parasitology ,Circadian rhythm ,Onchocerca ,Skin Diseases, Parasitic ,Saturation (chemistry) - Published
- 1967
17. [Anesthesia in surgery of chronic otitis]
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J, Thuries, J, Guyon, P, Brossard, and J L, Gouzi
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Otitis Media ,Humans ,Anesthesia - Published
- 1965
18. [Pancreas histology in a tolbutamide-treated diabetic]
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J, VERNE, J, GUYON, and KERNEIS
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Tolbutamide ,Diabetes Mellitus ,Humans ,Hypoglycemic Agents ,Pancreas - Published
- 1957
19. [Bronchoscopy under anesthesia in a state of wakefulness]
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J, Thuries, J, Guyon, and M, Poncet
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Bronchoscopy ,Anesthesia ,Dextromoramide - Published
- 1965
20. 1st results of the treatment of leprosy with rifampicin in New Caledonia
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G, Chanalet, J, Guyon, J, Beaute, F, Parc, and F, Boutier
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Adult ,Male ,Leprosy ,Humans ,Female ,Middle Aged ,Rifampin ,Pacific Islands ,Prognosis - Published
- 1972
21. The instrument suite of the European Spallation Source
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S. Stepanyan, F. Masi, Gergely Nagy, Henrich Frielinghaus, R. Kiehn, Richard Hall-Wilton, Stewart F. Parker, Judith E. Houston, C. Bovo, Uwe Filges, Joshaniel F. K. Cooper, Jochen Stahn, I. Herranz, R. Vivanco, Zahir Salhi, S. Klimko, A. Gussen, M. Huerta, Isabel Llamas-Jansa, S. Rodrigues, X. Fabrèges, Thomas Arnold, Esko Oksanen, Melissa Sharp, F. Porcher, F.Y. Moreira, Wiebke Lohstroh, N. Webb, F. Piscitelli, Paul Gregory Freeman, Roberto Senesi, S. Petersson Årsköld, Winfried Petry, Niels Bech Christensen, L. Di Fresco, Martin Müller, Henrik Carlsen, M. Magán, Jürg Schefer, K. Lieutenant, G. Laszlo, Kim Lefmann, Paul F. Henry, C. Scatigno, A. De Bonis, Artur Glavic, Jürgen Neuhaus, Robin Woracek, A. Goukassov, M. Rouijaa, Burkhard Schillinger, Přemysl Beran, H. Kämmerling, Richard K. Heenan, P. Lukáš, H. Wacklin-Knecht, A. Schwaab, Mads F. Bertelsen, Rasmus Toft-Petersen, Linda Udby, Marco Zanatta, Giuseppe Gorini, Ibon Bustinduy, Bjørn C. Hauback, O.G. del Moral, R.E. Lechner, M. Lerche, Th. Kittelmann, Ken Haste Andersen, M. A. Olsen, Henrik M. Rønnow, J.W. Taylor, J. Guyon Le Bouffy, Pascale P. Deen, Aureliano Tartaglione, J. Jestin, Sean Langridge, Ph. Schmakat, D.J. Siemers, D. Martín-Rodríguez, M. Morgano, B. Annighöfer, C.I. Lopez, Oliver Kirstein, Mikhail Feygenson, M. Zanetti, S. Pullen, F. Sordo, S. Bellissima, Andrew Jackson, Francesco Sacchetti, J. Elmer, D. Mannix, P. Tozzi, Th. Robillard, A. Poqué, J. Fenske, Jemel P. Aguilar, M. Seifert, G. Fabrèges, E. Abad, J. Šaroun, A. Wischnewski, Félix J. Villacorta, Monika Hartl, Giuseppe Aprigliano, S. Schütz, Michael Schulz, Ch. Niedermayer, Elbio Calzada, Heloisa N. Bordallo, A. Heynen, Anna Fedrigo, M. Olsson, Sebastian Jaksch, Markus Strobl, Tadeusz Kozielewski, José Luis Martínez, Grzegorz Nowak, Mogens Christensen, Felix Fernandez-Alonso, S. Kennedy, A. Hiess, M.E. Hagen, A. Schreyer, Alessandro Paciaroni, Caterina Petrillo, M. Arai, P. Galsworthy, Jörg Voigt, Andrea Orecchini, G. Scionti, M. Mosconi, Ch. Alba-Simionesco, I. Stefanescu, Ralf Engels, S. Longeville, J. Nightingale, S. Desert, Márton Markó, H. Schneider, Kalliopi Kanaki, Stuart Ansell, Th. Brückel, M. A. H. Chowdhury, Daniele Colognesi, G. Bakedano, Ch. Klauser, D. Turner, M. Koenen, D. Raspino, K. Iversen, Sonja Holm-Dahlin, Dorothea Pfeiffer, P. Luna, Ferenc Mezei, L. del Rosso, Anette Vickery, Carla Andreani, Earl Babcock, Werner Schweika, J. O. Birk, Anton Khaplanov, U. Bengaard Hansen, Th. Dupont, William Halcrow, P. Harbott, Nikolaos Tsapatsaris, P. Lavie, Eberhard Lehmann, L. Whitelegg, Romuald Hanslik, A. Orszulik, S. Butterweck, R. Kolevatov, Ph. Bourges, Dimitri N. Argyriou, L. Loaiza, Nicolo Violini, LLB - Nouvelles frontières dans les matériaux quantiques (NFMQ), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut Laue-Langevin (ILL), ESS, Lund, Swedish Research Council, Centre National de la Recherche Scientifique (France), Science and Technology Facilities Council (UK), European Commission, ILL, Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Andersen, K, Argyriou, D, Jackson, A, Houston, J, Henry, P, Deen, P, Toft-Petersen, R, Beran, P, Strobl, M, Arnold, T, Wacklin-Knecht, H, Tsapatsaris, N, Oksanen, E, Woracek, R, Schweika, W, Mannix, D, Hiess, A, Kennedy, S, Kirstein, O, Petersson Arskold, S, Taylor, J, Hagen, M, Laszlo, G, Kanaki, K, Piscitelli, F, Khaplanov, A, Stefanescu, I, Kittelmann, T, Pfeiffer, D, Hall-Wilton, R, Lopez, C, Aprigliano, G, Whitelegg, L, Moreira, F, Olsson, M, Bordallo, H, Martin-Rodriguez, D, Schneider, H, Sharp, M, Hartl, M, Nagy, G, Ansell, S, Pullen, S, Vickery, A, Fedrigo, A, Mezei, F, Arai, M, Heenan, R, Halcrow, W, Turner, D, Raspino, D, Orszulik, A, Cooper, J, Webb, N, Galsworthy, P, Nightingale, J, Langridge, S, Elmer, J, Frielinghaus, H, Hanslik, R, Gussen, A, Jaksch, S, Engels, R, Kozielewski, T, Butterweck, S, Feygenson, M, Harbott, P, Poque, A, Schwaab, A, Lieutenant, K, Violini, N, Voigt, J, Bruckel, T, Koenen, M, Kammerling, H, Babcock, E, Salhi, Z, Wischnewski, A, Heynen, A, Desert, S, Jestin, J, Porcher, F, Fabreges, X, Fabreges, G, Annighofer, B, Klimko, S, Dupont, T, Robillard, T, Goukassov, A, Longeville, S, Alba-Simionesco, C, Bourges, P, Guyon Le Bouffy, J, Lavie, P, Rodrigues, S, Calzada, E, Lerche, M, Schillinger, B, Schmakat, P, Schulz, M, Seifert, M, Lohstroh, W, Petry, W, Neuhaus, J, Loaiza, L, Tartaglione, A, Glavic, A, Schutz, S, Stahn, J, Lehmann, E, Morgano, M, Schefer, J, Filges, U, Klauser, C, Niedermayer, C, Fenske, J, Nowak, G, Rouijaa, M, Siemers, D, Kiehn, R, Muller, M, Carlsen, H, Udby, L, Lefmann, K, Birk, J, Holm-Dahlin, S, Bertelsen, M, Hansen, U, Olsen, M, Christensen, M, Iversen, K, Christensen, N, Ronnow, H, Freeman, P, Hauback, B, Kolevatov, R, Llamas-Jansa, I, Orecchini, A, Sacchetti, F, Petrillo, C, Paciaroni, A, Tozzi, P, Zanatta, M, Luna, P, Herranz, I, del Moral, O, Huerta, M, Magan, M, Mosconi, M, Abad, E, Aguilar, J, Stepanyan, S, Bakedano, G, Vivanco, R, Bustinduy, I, Sordo, F, Martinez, J, Lechner, R, Villacorta, F, Saroun, J, Lukas, P, Marko, M, Zanetti, M, Bellissima, S, del Rosso, L, Masi, F, Bovo, C, Chowdhury, M, De Bonis, A, Di Fresco, L, Scatigno, C, Parker, S, Fernandez-Alonso, F, Colognesi, D, Senesi, R, Andreani, C, Gorini, G, Scionti, G, and Schreyer, A
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powder diffractometer ,materials science ,guide ,Accelerator-based neutron facilitie ,Slow neutron scattering ,02 engineering and technology ,spin dynamics ,7. Clean energy ,01 natural sciences ,neutron-scattering ,test beamline ,[SPI]Engineering Sciences [physics] ,Conceptual design ,Spallation ,Pulsed neutron instrumentation ,Instrumentation ,ComputingMilieux_MISCELLANEOUS ,lattice ,Physics ,Accelerator-based neutron facilities ,ESS instrument suite ,[PHYS]Physics [physics] ,Settore FIS/03 ,Suite ,021001 nanoscience & nanotechnology ,ddc ,accelerator-based neutron facilities ,slow neutron scattering ,0210 nano-technology ,Nuclear and High Energy Physics ,ess instrument suite ,F300 ,time-of-flight ,antiferromagnetic order ,0103 physical sciences ,Neutron ,ddc:530 ,Aerospace engineering ,[PHYS.COND]Physics [physics]/Condensed Matter [cond-mat] ,010306 general physics ,Spectrometer ,business.industry ,pulsed neutron instrumentation ,Neutron radiation ,Beamline ,Neutron source ,spectrometer ,business - Abstract
The MIRACLES team., An overview is provided of the 15 neutron beam instruments making up the initial instrument suite of the European Spallation Source (ESS), and being made available to the neutron user community. The ESS neutron source consists of a high-power accelerator and target station, providing a unique long-pulse time structure of slow neutrons. The design considerations behind the time structure, moderator geometry and instrument layout are presented. The 15-instrument suite consists of two small-angle instruments, two reflectometers, an imaging beamline, two single-crystal diffractometers; one for macromolecular crystallography and one for magnetism, two powder diffractometers, and an engineering diffractometer, as well as an array of five inelastic instruments comprising two chopper spectrometers, an inverse-geometry single-crystal excitations spectrometer, an instrument for vibrational spectroscopy and a high-resolution backscattering spectrometer. The conceptual design, performance and scientific drivers of each of these instruments are described. All of the instruments are designed to provide breakthrough new scientific capability, not currently available at existing facilities, building on the inherent strengths of the ESS long-pulse neutron source of high flux, flexible resolution and large bandwidth. Each of them is predicted to provide world-leading performance at an accelerator power of 2 MW. This technical capability translates into a very broad range of scientific capabilities. The composition of the instrument suite has been chosen to maximise the breadth and depth of the scientific impact of the early years of the ESS, and provide a solid base for completion and further expansion of the facility., Some of the work described here is part of projects that have received funding from the European Union’s Horizon 2020 research programme: SINE 2020 under grant agreement number 654000, BrightnESS under grant agreement number 676548, and SoNDe under grant agreement number 654124. Financial support for the fast-shutter upgrade for FREIA from Swedish Research Council VR, grant no 2018-05013, is acknowledged. The VESPA team gratefully acknowledges the Science & Technology Facilities Council (STFC) and the CNR , within the CNR-STFC Agreement (2014–2020) No. 3420.
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22. Prime decorazioni nelle catacombe romane. Prove di laboratorio, invenzioni e remakes
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BISCONTI, FABRIZIO, V. Fiocchi Nicolai, J. Guyon, and Bisconti, Fabrizio
- Abstract
Prendendo le mosse dai nuclei più antichi delle catacombe romane, si percorre il primo segmento della storia della pittura cimiteriale cristiana romana, alla luce delle più recenti e accreditate acquisizioni cronologiche relative alla genesi e ai primi sviluppi delle necropoli ipogee tardoantiche di diritto privato e comunitario. L'analisi entra nel merito della naturale evoluzione dell'arte vesuviana e, in particolare, prende le mosse dal II "stile" pompeiano per arrivare alla produzione artistica tardoantica, così come è espressa nelle pareti delle domus romane ed ostiensi. Si passa, poi, ad osservare il multiforme repertorio cosmico e dionisiaco, che compare negli spazi disegnati dalle tipiche linee rosso-verdi, per evidenziarne gli elementi che perdureranno anche nella pittura cimiteriale più matura. Lo studio si conclude con il censimento delle personificazioni, che denunciano un'evoluzione semantica cristiana (orante, pastore, filosofo, pescatore) e con le prime incerte, eppure eloquenti, scene di ispirazione biblica, che mostrano una tensione significativa di tipo esplicitamente soterico (Giona, Mosè Lazzaro, Samaritana, Abramo, Daniele) o di ascendenza e riconnotazione realistica e/o funeraria (fossori, banchetti).
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- 2006
23. Estimation of Dislocation Densities With Nondestructive Scanning Electron Microscope Techniques: Application to Gallium Nitride.
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Mandal A, Beausir B, Guyon J, Taupin V, and Guitton A
- Abstract
Characterizing threading dislocations (TDs) in gallium nitride (GaN) semiconductors is crucial for ensuring the reliability of semiconductor devices. The current research addresses this issue by combining two techniques using a scanning electron microscope, namely electron channeling contrast imaging (ECCI) and high-resolution electron backscattered diffraction (HR-EBSD). It is a comparative study of these techniques to underscore how they perform in the evaluation of TD densities in GaN epitaxial layers. Experiments reveal that the dislocation line vectors mostly deviate from the growth direction of the film, i.e., ∦ [0001], followed by edge-type dislocations (dislocation lines || [0001]) with insignificant screw character. Furthermore, TDs from the dislocation clusters are characterized as edge- and (edge + mixed)-type TDs. By combining ECCI counting of dislocations and HR-EBSD description of geometrically necessary dislocation density type, it is possible to measure the total TD density and provide the proportion of pure (edge and screw) and mixed TDs. It has also been observed from the analyses of residual elastic strain fields and lattice rotations that it is not possible to identify individual dislocations for the spatial resolution of 50 nm in HR-EBSD. Nevertheless, ECCI and HR-EBSD can be complementarily used to count and characterize the TDs., Competing Interests: Conflict of Interest: The authors declare that they have no competing interest., (© The Author(s) 2025. Published by Oxford University Press on behalf of the Microscopy Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)
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- 2025
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24. Psychoactive cocktail consumption on Reunion Island: A case report.
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Guyon J, Maillot A, Bastard S, Weisse F, Daveluy A, and Mété D
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Reunion Island is a French department located in the southwestern Indian Ocean, with distinct trends in drug use, drug diversion and intoxication compared with metropolitan France (e.g. the misuse of drugs - clonazepam and trihexyphenidyl - combined with cannabis or cocaine, which is not observed in metropolitan France). The authors report a case of atypical intoxication in a 16-year-old female who consumed cannabis in conjunction with an unusual powdered mixture containing psychotropic substances. The intoxication led to confusion, hallucinations, sinus tachycardia and hospitalization. A comprehensive high-resolution mass spectrometry and liquid-chromatography mass spectrometry analysis of her plasma, her urine and a powder found in her possession revealed the presence of the same 5 medicines: citalopram/escitalopram, paroxetine, sertraline, venlafaxine and trihexyphenidyl. This case underscores the intricate interactions between psychoactive substances that are never prescribed together in clinical settings, along with the issue of diverted prescription drugs like trihexyphenidyl. It also emphasizes the potential circulation and use of crushed mixtures of medication for recreational purpose. Fortunately, powder analysis provided crucial insight to understand the intoxication., (© The Author(s) 2025. Published by Oxford University Press. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site–for further information please contact journals.permissions@oup.com.)
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- 2025
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25. Exploiting metabolic vulnerability in glioblastoma using a brain-penetrant drug with a safe profile.
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Burban A, Tessier C, Larroquette M, Guyon J, Lubiato C, Pinglaut M, Toujas M, Galvis J, Dartigues B, Georget E, Luchman HA, Weiss S, Cappellen D, Nicot N, Klink B, Nikolski M, Brisson L, Mathivet T, Bikfalvi A, Daubon T, and Sharanek A
- Abstract
Glioblastoma is one of the most treatment-resistant and lethal cancers, with a subset of self-renewing brain tumour stem cells (BTSCs), driving therapy resistance and relapse. Here, we report that mubritinib effectively impairs BTSC stemness and growth. Mechanistically, bioenergetic assays and rescue experiments showed that mubritinib targets complex I of the electron transport chain, thereby impairing BTSC self-renewal and proliferation. Gene expression profiling and Western blot analysis revealed that mubritinib disrupts the AMPK/p27
Kip1 pathway, leading to cell-cycle impairment. By employing in vivo pharmacokinetic assays, we established that mubritinib crosses the blood-brain barrier. Using preclinical patient-derived and syngeneic models, we demonstrated that mubritinib delays glioblastoma progression and extends animal survival. Moreover, combining mubritinib with radiotherapy or chemotherapy offers survival advantage to animals. Notably, we showed that mubritinib alleviates hypoxia, thereby enhancing ROS generation, DNA damage, and apoptosis in tumours when combined with radiotherapy. Encouragingly, toxicological and behavioural studies revealed that mubritinib is well tolerated and spares normal cells. Our findings underscore the promising therapeutic potential of mubritinib, warranting its further exploration in clinic for glioblastoma therapy., Competing Interests: Disclosure and competing interests statement. The authors declare no competing interests., (© 2025. The Author(s).)- Published
- 2025
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26. Using DIMet for Differential Analysis of Labeled Metabolomics Data: A Step-by-step Guide Showcasing the Glioblastoma Metabolism.
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Galvis J, Guyon J, Daubon T, and Nikolski M
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Stable-isotope resolved metabolomics (SIRM) is a powerful approach for characterizing metabolic states in cells and organisms. By incorporating isotopes, such as
13 C, into substrates, researchers can trace reaction rates across specific metabolic pathways. Integrating metabolomics data with gene expression profiles further enriches the analysis, as we demonstrated in our prior study on glioblastoma metabolic symbiosis. However, the bioinformatics tools for analyzing tracer metabolomics data have been limited. In this protocol, we encourage the researchers to use SIRM and transcriptomics data and to perform the downstream analysis using our software tool DIMet. Indeed, DIMet is the first comprehensive tool designed for the differential analysis of tracer metabolomics data, alongside its integration with transcriptomics data. DIMet facilitates the analysis of stable-isotope labeling and metabolic abundances, offering a streamlined approach to infer metabolic changes without requiring complex flux analysis. Its pathway-based "metabologram" visualizations effectively integrate metabolomics and transcriptomics data, offering a versatile platform capable of analyzing corrected tracer datasets across diverse systems, organisms, and isotopes. We provide detailed steps for sample preparation and data analysis using DIMet through its intuitive, web-based Galaxy interface. To showcase DIMet's capabilities, we analyzed LDHA/B knockout glioblastoma cell lines compared to controls. Accessible to all researchers through Galaxy, DIMet is free, user-friendly, and open source, making it a valuable resource for advancing metabolic research. Key features • Glioblastoma tumor spheroids in vitro replicate tumors' three-dimensional structure and natural nutrient, metabolite, and gas gradients, providing a more realistic model of tumor biology. • Joint analysis of tracer metabolomics and transcriptomics datasets provides deeper insights into the metabolic states of cells. • DIMet is a web-based tool for differential analysis and seamless integration of metabolomics and transcriptomics data, making it accessible and user-friendly. • DIMet enables researchers to infer metabolic changes, offering intuitive and visually appealing "metabologram" outputs, surpassing conventional visual representations commonly used in the field., Competing Interests: Competing interestsThere are no conflicts of interest or competing interests., (©Copyright : © 2025 The Authors; This is an open access article under the CC BY-NC license.)- Published
- 2025
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27. Letter to the Editor: The Cannabinoid Consumed Is Not Necessarily the One Expected: Recent Experience with Hexahydrocannabinol.
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Guyon J, Paradis C, Titier K, Braganca C, Peyre A, Nardon A, Daveluy A, Molimard M, Labadie M, and Castaing N
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- Humans, Dronabinol, Cannabinoids
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- 2024
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28. Generation of glioblastoma in mice engrafted with human cytomegalovirus-infected astrocytes.
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Guyon J, Haidar Ahmad S, El Baba R, Le Quang M, Bikfalvi A, Daubon T, and Herbein G
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- Animals, Humans, Mice, Brain Neoplasms virology, Brain Neoplasms pathology, Cytomegalovirus Infections virology, Cell Line, Tumor, Xenograft Model Antitumor Assays, Glioblastoma virology, Glioblastoma pathology, Glioblastoma genetics, Cytomegalovirus genetics, Astrocytes metabolism, Astrocytes virology
- Abstract
Mounting evidence is identifying human cytomegalovirus (HCMV) as a potential oncogenic virus. HCMV has been detected in glioblastoma multiforme (GB). Herewith, we present the first experimental evidence for the generation of CMV-Elicited Glioblastoma Cells (CEGBCs) possessing glioblastoma-like traits that lead to the formation of glioblastoma in orthotopically xenografted mice. In addition to the already reported oncogenic HCMV-DB strain, we isolated three HCMV clinical strains from GB tissues that transformed HAs toward CEGBCs and generated spheroids from CEGBCs that resulted in the appearance of glioblastoma-like tumors in xenografted mice. These tumors were nestin-positive mostly in the invasive part surrounded by GFAP-positive reactive astrocytes. The glioblastoma immunohistochemistry phenotype was confirmed by EGFR and cMet gene amplification in the tumor parallel to the detection of HCMV IE and UL69 genes and proteins. Our results fit with an HCMV-induced glioblastoma model of oncogenesis in vivo which will open the door to new therapeutic approaches and assess the anti-HCMV treatment as well as immunotherapy in fighting GB which is characterized by poor prognosis., (© 2024. The Author(s).)
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- 2024
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29. DIMet: an open-source tool for differential analysis of targeted isotope-labeled metabolomics data.
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Galvis J, Guyon J, Dartigues B, Hecht H, Grüning B, Specque F, Soueidan H, Karkar S, Daubon T, and Nikolski M
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- Humans, Glioblastoma metabolism, Cell Line, Tumor, Metabolomics methods, Software, Isotope Labeling methods
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Motivation: Many diseases, such as cancer, are characterized by an alteration of cellular metabolism allowing cells to adapt to changes in the microenvironment. Stable isotope-resolved metabolomics (SIRM) and downstream data analyses are widely used techniques for unraveling cells' metabolic activity to understand the altered functioning of metabolic pathways in the diseased state. While a number of bioinformatic solutions exist for the differential analysis of SIRM data, there is currently no available resource providing a comprehensive toolbox., Results: In this work, we present DIMet, a one-stop comprehensive tool for differential analysis of targeted tracer data. DIMet accepts metabolite total abundances, isotopologue contributions, and isotopic mean enrichment, and supports differential comparison (pairwise and multi-group), time-series analyses, and labeling profile comparison. Moreover, it integrates transcriptomics and targeted metabolomics data through network-based metabolograms. We illustrate the use of DIMet in real SIRM datasets obtained from Glioblastoma P3 cell-line samples. DIMet is open-source, and is readily available for routine downstream analysis of isotope-labeled targeted metabolomics data, as it can be used both in the command line interface or as a complete toolkit in the public Galaxy Europe and Workfow4Metabolomics web platforms., Availability and Implementation: DIMet is freely available at https://github.com/cbib/DIMet, and through https://usegalaxy.eu and https://workflow4metabolomics.usegalaxy.fr. All the datasets are available at Zenodo https://zenodo.org/records/10925786., (© The Author(s) 2024. Published by Oxford University Press.)
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- 2024
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30. SUMOylation controls Hu antigen R posttranscriptional activity in liver cancer.
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Lachiondo-Ortega S, Rejano-Gordillo CM, Simon J, Lopitz-Otsoa F, C Delgado T, Mazan-Mamczarz K, Goikoetxea-Usandizaga N, Zapata-Pavas LE, García-Del Río A, Guerra P, Peña-Sanfélix P, Hermán-Sánchez N, Al-Abdulla R, Fernandez-Rodríguez C, Azkargorta M, Velázquez-Cruz A, Guyon J, Martín C, Zalamea JD, Egia-Mendikute L, Sanz-Parra A, Serrano-Maciá M, González-Recio I, Gonzalez-Lopez M, Martínez-Cruz LA, Pontisso P, Aransay AM, Barrio R, Sutherland JD, Abrescia NGA, Elortza F, Lujambio A, Banales JM, Luque RM, Gahete MD, Palazón A, Avila MA, G Marin JJ, De S, Daubon T, Díaz-Quintana A, Díaz-Moreno I, Gorospe M, Rodríguez MS, and Martínez-Chantar ML
- Subjects
- Animals, Humans, Mice, Disease Models, Animal, ELAV-Like Protein 1 metabolism, RNA metabolism, Sumoylation, Carcinoma, Hepatocellular metabolism, Liver Neoplasms pathology
- Abstract
The posttranslational modification of proteins critically influences many biological processes and is a key mechanism that regulates the function of the RNA-binding protein Hu antigen R (HuR), a hub in liver cancer. Here, we show that HuR is SUMOylated in the tumor sections of patients with hepatocellular carcinoma in contrast to the surrounding tissue, as well as in human cell line and mouse models of the disease. SUMOylation of HuR promotes major cancer hallmarks, namely proliferation and invasion, whereas the absence of HuR SUMOylation results in a senescent phenotype with dysfunctional mitochondria and endoplasmic reticulum. Mechanistically, SUMOylation induces a structural rearrangement of the RNA recognition motifs that modulates HuR binding affinity to its target RNAs, further modifying the transcriptomic profile toward hepatic tumor progression. Overall, SUMOylation constitutes a mechanism of HuR regulation that could be potentially exploited as a therapeutic strategy for liver cancer., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
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- 2024
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31. New insights into the role of thrombospondin-1 in glioblastoma development.
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Bikfalvi A, Guyon J, and Daubon T
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- Humans, Tumor Microenvironment, Glioblastoma genetics, Glioblastoma drug therapy, Glioblastoma pathology, Brain Neoplasms genetics, Brain Neoplasms pathology
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Glioblastoma (GB), the most malignant subtype of diffuse glioma, is highly aggressive, invasive and vascularized. Its median survival is still short even with maximum standard care. There is a need to identify potential new molecules and mechanisms, that are involved in the interactions of GB cells with the tumor microenvironment (TME), for therapeutic intervention. Thrombospondin-1 (TSP1) is a multi-faceted matricellular protein which plays a significant role in development, physiology and pathology including cancer. Recent studies have pinpoint an important role of TSP1 in GB development which will be summarized and discussed herein. We will discuss studies, mainly from preclinical research, which should lead to a deeper understanding of TSP1's role in GB development. We will also discuss some issues with regard to the use of this knowledge for the clinic., Competing Interests: Declaration of Competing Interest There is no conflict of interest to declare., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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32. Histological analysis of invasive glioblastoma organoids embedded in a 3D collagen matrix.
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Guyon J and Daubon T
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- Humans, Organoids, Collagen, Histological Techniques, Paraffin, Glioblastoma
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Organoids are unique tools to mimic how tumors evolve in a 3D environment. Here, we present a protocol to embed spheroids invading a 3D matrix into a paraffin mold. We describe steps for preparing spheroids, collagen and agarose inclusion, and paraffinization. We then detail procedures for sectioning, staining, and visualization. This protocol allows histological identification of markers expressed in cells escaping the tumor. For complete details on the use and execution of this protocol, please refer to Guyon et al. (2022).
1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2023
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33. GAP43-dependent mitochondria transfer from astrocytes enhances glioblastoma tumorigenicity.
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Watson DC, Bayik D, Storevik S, Moreino SS, Sprowls SA, Han J, Augustsson MT, Lauko A, Sravya P, Røsland GV, Troike K, Tronstad KJ, Wang S, Sarnow K, Kay K, Lunavat TR, Silver DJ, Dayal S, Joseph JV, Mulkearns-Hubert E, Ystaas LAR, Deshpande G, Guyon J, Zhou Y, Magaut CR, Seder J, Neises L, Williford SE, Meiser J, Scott AJ, Sajjakulnukit P, Mears JA, Bjerkvig R, Chakraborty A, Daubon T, Cheng F, Lyssiotis CA, Wahl DR, Hjelmeland AB, Hossain JA, Miletic H, and Lathia JD
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- Humans, Astrocytes metabolism, Astrocytes pathology, GAP-43 Protein metabolism, GAP-43 Protein therapeutic use, Axons metabolism, Axons pathology, Cell Line, Tumor, Nerve Regeneration, Mitochondria metabolism, Mitochondria pathology, Glioblastoma
- Abstract
The transfer of intact mitochondria between heterogeneous cell types has been confirmed in various settings, including cancer. However, the functional implications of mitochondria transfer on tumor biology are poorly understood. Here we show that mitochondria transfer is a prevalent phenomenon in glioblastoma (GBM), the most frequent and malignant primary brain tumor. We identified horizontal mitochondria transfer from astrocytes as a mechanism that enhances tumorigenesis in GBM. This transfer is dependent on network-forming intercellular connections between GBM cells and astrocytes, which are facilitated by growth-associated protein 43 (GAP43), a protein involved in neuron axon regeneration and astrocyte reactivity. The acquisition of astrocyte mitochondria drives an increase in mitochondrial respiration and upregulation of metabolic pathways linked to proliferation and tumorigenicity. Functionally, uptake of astrocyte mitochondria promotes cell cycle progression to proliferative G2/M phases and enhances self-renewal and tumorigenicity of GBM. Collectively, our findings reveal a host-tumor interaction that drives proliferation and self-renewal of cancer cells, providing opportunities for therapeutic development., (© 2023. The Author(s).)
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- 2023
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34. Lactate dehydrogenases promote glioblastoma growth and invasion via a metabolic symbiosis.
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Guyon J, Fernandez-Moncada I, Larrieu CM, Bouchez CL, Pagano Zottola AC, Galvis J, Chouleur T, Burban A, Joseph K, Ravi VM, Espedal H, Røsland GV, Daher B, Barre A, Dartigues B, Karkar S, Rudewicz J, Romero-Garmendia I, Klink B, Grützmann K, Derieppe MA, Molinié T, Obad N, Léon C, Seano G, Miletic H, Heiland DH, Marsicano G, Nikolski M, Bjerkvig R, Bikfalvi A, and Daubon T
- Subjects
- Animals, Mice, Lactic Acid, Metabolomics, Lactate Dehydrogenases, Glioblastoma enzymology, Glioblastoma pathology, Brain Neoplasms enzymology, Brain Neoplasms pathology
- Abstract
Lactate is a central metabolite in brain physiology but also contributes to tumor development. Glioblastoma (GB) is the most common and malignant primary brain tumor in adults, recognized by angiogenic and invasive growth, in addition to its altered metabolism. We show herein that lactate fuels GB anaplerosis by replenishing the tricarboxylic acid (TCA) cycle in absence of glucose. Lactate dehydrogenases (LDHA and LDHB), which we found spatially expressed in GB tissues, catalyze the interconversion of pyruvate and lactate. However, ablation of both LDH isoforms, but not only one, led to a reduction in tumor growth and an increase in mouse survival. Comparative transcriptomics and metabolomics revealed metabolic rewiring involving high oxidative phosphorylation (OXPHOS) in the LDHA/B KO group which sensitized tumors to cranial irradiation, thus improving mouse survival. When mice were treated with the antiepileptic drug stiripentol, which targets LDH activity, tumor growth decreased. Our findings unveil the complex metabolic network in which both LDHA and LDHB are integrated and show that the combined inhibition of LDHA and LDHB strongly sensitizes GB to therapy., (© 2022 The Authors. Published under the terms of the CC BY 4.0 license.)
- Published
- 2022
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35. Glioblastoma cell motility depends on enhanced oxidative stress coupled with mobilization of a sulfurtransferase.
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Saurty-Seerunghen MS, Daubon T, Bellenger L, Delaunay V, Castro G, Guyon J, Rezk A, Fabrega S, Idbaih A, Almairac F, Burel-Vandenbos F, Turchi L, Duplus E, Virolle T, Peyrin JM, Antoniewski C, Chneiweiss H, El-Habr EA, and Junier MP
- Subjects
- Mice, Animals, Cysteine metabolism, Sulfurtransferases genetics, Sulfurtransferases metabolism, Oxidative Stress, Cell Movement genetics, Glioblastoma genetics
- Abstract
Cell motility is critical for tumor malignancy. Metabolism being an obligatory step in shaping cell behavior, we looked for metabolic weaknesses shared by motile cells across the diverse genetic contexts of patients' glioblastoma. Computational analyses of single-cell transcriptomes from thirty patients' tumors isolated cells with high motile potential and highlighted their metabolic specificities. These cells were characterized by enhanced mitochondrial load and oxidative stress coupled with mobilization of the cysteine metabolism enzyme 3-Mercaptopyruvate sulfurtransferase (MPST). Functional assays with patients' tumor-derived cells and -tissue organoids, and genetic and pharmacological manipulations confirmed that the cells depend on enhanced ROS production and MPST activity for their motility. MPST action involved protection of protein cysteine residues from damaging hyperoxidation. Its knockdown translated in reduced tumor burden, and a robust increase in mice survival. Starting from cell-by-cell analyses of the patients' tumors, our work unravels metabolic dependencies of cell malignancy maintained across heterogeneous genomic landscapes., (© 2022. The Author(s).)
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- 2022
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36. Secondary Hardening of a High-N Ni-Free Stainless Steel.
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Siredey-Schwaller N, Charbonnier P, Zhang Y, Guyon J, Perroud O, and Laheurte P
- Abstract
High-N Ni-free stainless steels are used for their excellent mechanical properties combined with their high corrosion resistance, especially for biomedical applications. Even though it is well-known that secondary hardening during annealing after cold working has been observed in many materials, this phenomenon was not reported for these materials, one of the best known being Biodur108©, although numerous efforts have been made to increase its hardness. In this work, thermomechanical treatments at low temperature of cold-deformed Biodur108© were conducted to increase the hardness. Hardness as high as 830 Hv was obtained. For this material, the annealing of a deformed sample at intermediate temperature leads to a secondary hardening phenomenon. The mechanisms responsible for this secondary hardening were analyzed. It was found that for deformed samples, annealing at 575 °C leads to the formation of small Cr
2 N precipitates along grain boundaries and sub-grain boundaries, and simultaneously with a new body-centered cubic (BCC) phase that possesses a super structure. The newly formed phases have sub-micrometric grain sizes.- Published
- 2022
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37. A UPLC-MS/MS Method for Plasma Biological Monitoring of Nirmatrelvir and Ritonavir in the Context of SARS-CoV-2 Infection and Application to a Case.
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Guyon J, Novion M, Fulda V, Ducint D, Molimard M, Couzi L, Kaminski H, Salvo F, and Bouchet S
- Subjects
- Biological Monitoring, Chromatography, High Pressure Liquid methods, Chromatography, Liquid, Humans, Immunosuppressive Agents, Reproducibility of Results, Ritonavir, SARS-CoV-2, Tacrolimus, Tandem Mass Spectrometry methods, COVID-19 Drug Treatment
- Abstract
Nirmatrelvir/ritonavir association has been authorized for conditional use in the treatment of COVID-19, especially in solid-organ transplant recipients who did not respond to vaccine and are still at high risk of severe disease. This combination remains at risk of drug interactions with immunosuppressants, so monitoring drug levels seems necessary. After a simple protein precipitation of plasma sample, analytes were analyzed using an ultrahigh performance liquid chromatography system coupled with tandem mass spectrometry in a positive ionization mode. Validation procedures were based on the guidelines on bioanalytical methods issued by the European Medicine Agency. The analysis time was 4 min per run. The calibration curves were linear over the range from 10 to 1000 ng/mL for ritonavir and 40 to 4000 ng/mL for nirmatrelvir, with coefficients of correlation above 0.99 for all analytes. Intra-/interday imprecisions were below 10%. The analytical method also meets criteria of matrix effect, carryover, dilution integrity, and stability. In the context of a SARS-CoV-2 infection in a renal transplant recipient, we present a case of tacrolimus overdose with serious adverse events despite discontinuation of nirmatrelvir and ritonavir. The patient had still effective concentrations of nirmatrelvir and tacrolimus 4 days after drug discontinuation. This method was successfully applied for therapeutic drug monitoring in clinical practice.
- Published
- 2022
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38. An Orthotopic Model of Glioblastoma Is Resistant to Radiodynamic Therapy with 5-AminoLevulinic Acid.
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Dupin C, Sutter J, Amintas S, Derieppe MA, Lalanne M, Coulibaly S, Guyon J, Daubon T, Boutin J, Blouin JM, Richard E, Moreau-Gaudry F, Bedel A, Vendrely V, and Dabernat S
- Abstract
Radiosensitization of glioblastoma is a major ambition to increase the survival of this incurable cancer. The 5-aminolevulinic acid (5-ALA) is metabolized by the heme biosynthesis pathway. 5-ALA overload leads to the accumulation of the intermediate fluorescent metabolite protoporphyrin IX (PpIX) with a radiosensitization potential, never tested in a relevant model of glioblastoma. We used a patient-derived tumor cell line grafted orthotopically to create a brain tumor model. We evaluated tumor growth and tumor burden after different regimens of encephalic multifractionated radiation therapy with or without 5-ALA. A fractionation scheme of 5 × 2 Gy three times a week resulted in intermediate survival [48-62 days] compared to 0 Gy (15-24 days), 3 × 2 Gy (41-47 days) and, 5 × 3 Gy (73-83 days). Survival was correlated to tumor growth. Tumor growth and survival were similar after 5 × 2 Gy irradiations, regardless of 5-ALA treatment (RT group (53-67 days), RT+5-ALA group (40-74 days), HR = 1.57, p = 0.24). Spheroid growth and survival were diminished by radiotherapy in vitro, unchanged by 5-ALA pre-treatment, confirming the in vivo results. The analysis of two additional stem-like patient-derived cell lines confirmed the absence of radiosensitization by 5-ALA. Our study shows for the first time that in a preclinical tumor model relevant to human glioblastoma, treated as in clinical routine, 5-ALA administration, although leading to important accumulation of PpIX, does not potentiate radiotherapy.
- Published
- 2022
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39. Refining the Role of Pyruvate Dehydrogenase Kinases in Glioblastoma Development.
- Author
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Larrieu CM, Storevik S, Guyon J, Pagano Zottola AC, Bouchez CL, Derieppe MA, Tan TZ, Miletic H, Lorens J, Tronstad KJ, Daubon T, and Røsland GV
- Abstract
Glioblastoma (GB) are the most frequent brain cancers. Aggressive growth and limited treatment options induce a median survival of 12-15 months. In addition to highly proliferative and invasive properties, GB cells show cancer-associated metabolic characteristics such as increased aerobic glycolysis. Pyruvate dehydrogenase (PDH) is a key enzyme complex at the crossroads between lactic fermentation and oxidative pathways, finely regulated by PDH kinases (PDHKs). PDHKs are often overexpressed in cancer cells to facilitate high glycolytic flux. We hypothesized that targeting PDHKs, by disturbing cancer metabolic homeostasis, would alter GB progression and render cells vulnerable to additional cancer treatment. Using patient databases, distinct expression patterns of PDHK1 and PDHK2 in GB tissues were obvious. To disturb protumoral glycolysis, we modulated PDH activity through the genetic or pharmacological inhibition of PDHK in patient-derived stem-like spheroids. Striking effects of PDHKs inhibition using dichloroacetate were observed in vitro on cell morphology and metabolism, resulting in increased intracellular ROS levels and decreased proliferation and invasion. In vivo findings confirmed a reduction in tumor size and better survival of mice implanted with PDHK1 and PDHK2 knockout cells. Adding a radiotherapeutic protocol further resulted in a reduction in tumor size and improved mouse survival in our model.
- Published
- 2022
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40. TGF-β promotes microtube formation in glioblastoma through thrombospondin 1.
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Joseph JV, Magaut CR, Storevik S, Geraldo LH, Mathivet T, Latif MA, Rudewicz J, Guyon J, Gambaretti M, Haukas F, Trones A, Rømo Ystaas LA, Hossain JA, Ninzima S, Cuvellier S, Zhou W, Tomar T, Klink B, Rane L, Irving BK, Marrison J, O'Toole P, Wurdak H, Wang J, Di Z, Birkeland E, Berven FS, Winkler F, Kruyt FAE, Bikfalvi A, Bjerkvig R, Daubon T, and Miletic H
- Subjects
- Humans, Thrombospondin 1 genetics, Thrombospondin 1 metabolism, Transforming Growth Factor beta genetics, Transforming Growth Factor beta metabolism, Glioblastoma pathology, Glioma, Oligodendroglioma
- Abstract
Background: Microtubes (MTs), cytoplasmic extensions of glioma cells, are important cell communication structures promoting invasion and treatment resistance through network formation. MTs are abundant in chemoresistant gliomas, in particular, glioblastomas (GBMs), while they are uncommon in chemosensitive IDH-mutant and 1p/19q co-deleted oligodendrogliomas. The aim of this study was to identify potential signaling pathways involved in MT formation., Methods: Bioinformatics analysis of TCGA was performed to analyze differences between GBM and oligodendroglioma. Patient-derived GBM stem cell lines were used to investigate MT formation under transforming growth factor-beta (TGF-β) stimulation and inhibition in vitro and in vivo in an orthotopic xenograft model. RNA sequencing and proteomics were performed to detect commonalities and differences between GBM cell lines stimulated with TGF-β., Results: Analysis of TCGA data showed that the TGF-β pathway is highly activated in GBMs compared to oligodendroglial tumors. We demonstrated that TGF-β1 stimulation of GBM cell lines promotes enhanced MT formation and communication via calcium signaling. Inhibition of the TGF-β pathway significantly reduced MT formation and its associated invasion in vitro and in vivo. Downstream of TGF-β, we identified thrombospondin 1 (TSP1) as a potential mediator of MT formation in GBM through SMAD activation. TSP1 was upregulated upon TGF-β stimulation and enhanced MT formation, which was inhibited by TSP1 shRNAs in vitro and in vivo., Conclusion: TGF-β and its downstream mediator TSP1 are important mediators of the MT network in GBM and blocking this pathway could potentially help to break the complex MT-driven invasion/resistance network., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Neuro-Oncology.)
- Published
- 2022
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41. [Recommendations For The Management Of Spontaneous Intracerebral Hemorrhage During Hospitalization].
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Pigretti SG, Mirofsky M, García DE, Issac C, Valdez P, Persi GG, Mamani CE, Guyon J, Álvarez H, Montes M, Daza Aramayo JM, Iturrieta P, Chaves H, Sarmiento V, Tumino L, Domeniconi G, Castagna R, Sabio R, Videtta W, Ciarrocchi N, Lerman D, Dossi DE, Balian NR, Rufino Saravia G, Alet MJ, Rodríguez Lucci F, Ciardi C, Pujol Lereis V, Claverie S, Casanova M, González L, Mónaco JM, Cárdenas RE, Cirio JJ, Arturi J, Requejo F, Plou PL, Orzuza G, Bonardo P, Díaz MF, Payaslian S, Andrade MG, Gomez Schneider MM, Romano M, Colla Machado P, Arroyo J, Arcondo MF, Svampa S, Armenteros C, Tejada Jacob V, and Zurrú MC
- Subjects
- Humans, Adult, Middle Aged, Cerebral Hemorrhage therapy, Blood Pressure physiology, Hospitalization, Fibrinolytic Agents therapeutic use, Stroke etiology
- Abstract
Stroke is the leading cause of neurological disability in people over 40 years of age and the fourth leading cause of death in Argentina. In the last ten years, the indexed publications related to the treatment of ischemic stroke were more numerous than those of hemorrhagic stroke. The objective of this material is to provide local and updated recommendations for the management of patients with spontaneous intracerebral hemorrhage during hospitalization. For the writing of this manuscript, diferent specialists were convened to form working groups. Ten central topics expressed as epidemiology, initial care, imaging, blood pressure treatment, reversal of antithrombotics, indication for surgery, seizure prophylaxis, prognosis, prevention of complications and resumption of antithrombotics were raised. For each topic, the most frequent questions of daily practice were raised through PICO questions. After a systematic review of the literature, recommendations were generated, evaluated using the GRADE system and agreed between authors and patients.
- Published
- 2022
42. Association Between Antiangiogenic Drugs Used for Cancer Treatment and Artery Dissections or Aneurysms.
- Author
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Guyon J, Gouverneur A, Maumus-Robert S, Bérard X, Pariente A, Bikfalvi A, and Noize P
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- Angiogenesis Inhibitors adverse effects, Arteries, Humans, Aortic Dissection, Neoplasms
- Published
- 2021
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43. The Normal and Brain Tumor Vasculature: Morphological and Functional Characteristics and Therapeutic Targeting.
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Guyon J, Chapouly C, Andrique L, Bikfalvi A, and Daubon T
- Abstract
Glioblastoma is among the most common tumor of the central nervous system in adults. Overall survival has not significantly improved over the last decade, even with optimizing standard therapeutic care including extent of resection and radio- and chemotherapy. In this article, we review features of the brain vasculature found in healthy cerebral tissue and in glioblastoma. Brain vessels are of various sizes and composed of several vascular cell types. Non-vascular cells such as astrocytes or microglia also interact with the vasculature and play important roles. We also discuss in vitro engineered artificial blood vessels which may represent useful models for better understanding the tumor-vessel interaction. Finally, we summarize results from clinical trials with anti-angiogenic therapy alone or in combination, and discuss the value of these approaches for targeting glioblastoma., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Guyon, Chapouly, Andrique, Bikfalvi and Daubon.)
- Published
- 2021
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44. Co-culture of Glioblastoma Stem-like Cells on Patterned Neurons to Study Migration and Cellular Interactions.
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Guyon J, Strale PO, Romero-Garmendia I, Bikfalvi A, Studer V, and Daubon T
- Subjects
- Animals, Cell Line, Tumor, Cell Tracking, Glioma pathology, Humans, Image Processing, Computer-Assisted, Laminin pharmacology, Neoplastic Stem Cells drug effects, Neurons drug effects, Rats, Spheroids, Cellular drug effects, Spheroids, Cellular pathology, Brain Neoplasms pathology, Cell Communication drug effects, Cell Movement drug effects, Coculture Techniques methods, Glioblastoma pathology, Neoplastic Stem Cells pathology, Neurons pathology
- Abstract
Glioblastomas (GBMs), grade IV malignant gliomas, are one of the deadliest types of human cancer because of their aggressive characteristics. Despite significant advances in the genetics of these tumors, how GBM cells invade the healthy brain parenchyma is not well understood. Notably, it has been shown that GBM cells invade the peritumoral space via different routes; the main interest of this paper is the route along white matter tracts (WMTs). The interactions of tumor cells with the peritumoral nervous cell components are not well characterized. Herein, a method has been described that evaluates the impact of neurons on GBM cell invasion. This paper presents an advanced co-culture in vitro assay that mimics WMT invasion by analyzing the migration of GBM stem-like cells on neurons. The behavior of GBM cells in the presence of neurons is monitored by using an automated tracking procedure with open-source and free-access software. This method is useful for many applications, in particular, for functional and mechanistic studies as well as for analyzing the effects of pharmacological agents that can block GBM cell migration on neurons.
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- 2021
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45. A 3D Spheroid Model for Glioblastoma.
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Guyon J, Andrique L, Pujol N, Røsland GV, Recher G, Bikfalvi A, and Daubon T
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- Humans, Brain Neoplasms pathology, Cell Culture Techniques methods, Glioblastoma pathology, Imaging, Three-Dimensional methods, Spheroids, Cellular pathology
- Abstract
Two-dimensional (2D) cell cultures do not mimic in vivo tumor growth satisfactorily. Therefore, three-dimensional (3D) culture spheroid models were developed. These models may be particularly important in the field of neuro-oncology. Indeed, brain tumors have the tendency to invade the healthy brain environment. We describe herein an ideal 3D glioblastoma spheroid-based assay that we developed to study tumor invasion. We provide all technical details and analytical tools to successfully perform this assay.
- Published
- 2020
- Full Text
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46. The invasive proteome of glioblastoma revealed by laser-capture microdissection.
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Daubon T, Guyon J, Raymond AA, Dartigues B, Rudewicz J, Ezzoukhry Z, Dupuy JW, Herbert JMJ, Saltel F, Bjerkvig R, Nikolski M, and Bikfalvi A
- Abstract
Background: Glioblastomas are heterogeneous tumors composed of a necrotic and tumor core and an invasive periphery., Methods: Here, we performed a proteomics analysis of laser-capture micro-dissected glioblastoma core and invasive areas of patient-derived xenografts., Results: Bioinformatics analysis identified enriched proteins in central and invasive tumor areas. Novel markers of invasion were identified, the genes proteolipid protein 1 (PLP1) and Dynamin-1 (DNM1), which were subsequently validated in tumors and by functional assays., Conclusions: In summary, our results identify new networks and molecules that may play an important role in glioblastoma development and may constitute potential novel therapeutic targets., (© The Author(s) 2019. Published by Oxford University Press, the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)
- Published
- 2019
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47. In Situ Macroscopic Tensile Testing in SEM and Electron Channeling Contrast Imaging: Pencil Glide Evidenced in a Bulk β-Ti21S Polycrystal.
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Ben Haj Slama M, Maloufi N, Guyon J, Bahi S, Weiss L, and Guitton A
- Abstract
In this paper, we report the successful combination of macroscopic uniaxial tensile testing of bulk specimen combined with In situ dislocation-scale observations of the evolution of deformation microstructures during loading at several stress states. The dislocation-scale observations were performed by Accurate Electron Channeling Contrast Imaging in order to follow the defects evolution and their interactions with grain boundaries for several regions of interest during macroscopic loading. With this novel in situ procedure, the slip systems governing the deformation in polycrystalline bulk β-Ti21S are tracked during the macroscopic uniaxial tensile test. For instance, curved slip lines that are associated with "pencil glide" phenomenon and tangled dislocation networks are evidenced.
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- 2019
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48. A Dislocation-Scale Characterization of the Evolution of Deformation Microstructures around Nanoindentation Imprints in a TiAl Alloy.
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Guitton A, Kriaa H, Bouzy E, Guyon J, and Maloufi N
- Abstract
In this work, plastic deformation was locally introduced at room temperature by nanoindentation on a γ-TiAl-based alloy. Comprehensive analyses of microstructures were performed before and after deformation. In particular, the Burgers vectors, the line directions, and the mechanical twinning systems were studied via accurate electron channeling contrast imaging. Accommodation of the deformation are reported and a scenario is proposed. All features help to explain the poor ductility of the TiAl-based alloys at room temperature.
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- 2018
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49. Advancing FIB assisted 3D EBSD using a static sample setup.
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Guyon J, Gey N, Goran D, Chalal S, and Pérez-Willard F
- Abstract
A new setup for automatic 3D EBSD data collection in static mode has been developed using a conventional FIB-SEM system. This setup requires no stage or sample movements between the FIB milling and EBSD mapping. Its capabilities were tested experimentally on a coherent twin boundary of an INCONEL sample. Our result demonstrates that this static setup holds many advantages in terms of data throughput and quality as compared with other ones requiring stage/sample movements. The most important advantages are the better slice alignment and an improved orientation precision in 3D space, both being prerequisite for a reliable grain boundary characterization., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
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50. Orientation mapping by transmission-SEM with an on-axis detector.
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Fundenberger JJ, Bouzy E, Goran D, Guyon J, Yuan H, and Morawiec A
- Abstract
Conventional orientation mapping in a scanning electron microscope (SEM) is a valuable technique for characterizing crystalline materials, but its application to ultrafine or nano-grain materials is limited by its spatial resolution. The resolution can be increased by collecting transmission diffraction patterns in SEM. In previous works, such patterns were collected using off-axis detectors in nearly vertical position. To avoid some drawbacks of such arrangement, a new configuration was devised in which the scintillator is located underneath the thin foil on the optical axis of the microscope, and the light is reflected towards the camera by a mirror. This simple configuration gives intense patterns even at very low probe currents, and can be potentially used for collecting maps of relatively high spatial resolution. Example maps reveal details with dimensions of about 5nm. Because of its resolution and geometric simplicity, the proposed configuration will open new opportunities in SEM-based characterization of nanocrystalline materials., (Copyright © 2015 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
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