Auteurs, date et publication :
Auteurs V. E. Mayer , J. Lauth , J. Orivel
Publication : Insectes Sociaux
Date : 2025
Volume : 64
Issue : 3
Pages : 365-371
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Abstract Measuring leaf gas exchange from canopy leaves is fundamental for our understanding of photosynthesis and for a realistic representation of carbon uptake in vegetation models. Since canopy leaves are often difficult to reach, especially in tropical forests with emergent trees up to 60 m at remote places, canopy access techniques such as canopy cranes or towers have facilitated photosynthetic measurements. These structures are expensive and therefore not very common. As an alternative, branches are often cut to enable leaf gas exchange measurements. The effect of branch excision on leaf gas exchange rates should be minimized and quantified to evaluate possible bias. We compared light-saturated leaf net photosynthetic rates measured on excised and intact branches. We selected branches positioned at three canopy positions, estimated relative to the top of the canopy: upper sunlit foliage, middle canopy foliage, and lower canopy foliage. We studied the variation of the effects of branch excision and transport among branches at these different heights in the canopy. After excision and transport, light-saturated leaf net photosynthetic rates were close to zero for most leaves due to stomatal closure. However, when the branch had acclimated to its new environmental conditions?which took on average 20 min?light-saturated leaf net photosynthetic rates did not significantly differ between the excised and intact branches. We therefore conclude that branch excision does not affect the measurement of light-saturated leaf net photosynthesis, provided that the branch is recut under water and is allowed sufficient time to acclimate to its new environmental conditions.
Auteurs, date et publication :
Auteurs Lore T. Verryckt , Leandro Van Langenhove , Philippe Ciais , Elodie A. Courtois , Sara Vicca , Josep Peñuelas , Clément Stahl , Sabrina Coste , David S. Ellsworth , Juan M. Posada , Michael Obersteiner , Jérôme Chave , Ivan A. Janssens
Publication : Biotropica
Date : 2025
Volume : 52
Issue : 4
Pages : 608-615
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
In the initial, online publication, the authors' given names were captured as family names and vice versa. The names are correctly shown here. The original article has been corrected.
Auteurs, date et publication :
Auteurs Paloma Compes , Emeline Tabouret , Amandine Etcheverry , Carole Colin , Romain Appay , Nicolas Cordier , Jean Mosser , Olivier Chinot , Hervé Delingette , Nadine Girard , Henry Dufour , Philippe Metellus , Dominique Figarella-Branger
Publication : Journal of Neuro-Oncology
Date : 2019
Volume : 142
Issue : 3
Pages : 521-521
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Thomas Bourguignon , Thomas Drouet , Jan Šobotník , Robert Hanus , Yves Roisin
Publication : PloS one
Date : 2025
Volume : 10
Issue : 11
Pages : e0143776
Catégorie(s)
#CNRS #FORET NouraguesRésumé
BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is highly metastatic. Cabozantinib, an anti-angiogenic tyrosine kinase inhibitor that targets c-MET, provided interesting results in metastatic ccRCC treatment.
OBJECTIVE: To understand better the role of c-MET in ccRCC, we assessed its status in a population of patients with metastatic ccRCC.
PATIENTS AND METHODS: For this purpose, tumor samples were analyzed for c-MET expression by immunohistochemistry (IHC), for c-MET copy number alterations by fluorescence in situ hybridization (FISH), and for c-MET mutations by next generation sequencing (NGS) in a retrospective cohort of 90 primary ccRCC of patients with metastases treated by first-line sunitinib. The expression of c-MET was correlated with pathological, immunohistochemical (VEGFA, CAIX, PD-L1), clinical, and molecular criteria (VHL status) by univariate and multivariate analyses and to clinical outcome using Kaplan-Meier curves compared by log-rank test.
RESULTS: Of ccRCC, 31.1% had low c-MET expression (absent to weak intensity by IHC) versus 68.9% with high expression (moderate to strong intensity). High expression of c-MET was associated with a gain in FISH analysis (p=0.0284) without amplification. No mutations were detected in NGS. Moreover, high c-MET expression was associated with lymph node metastases (p=0.004), sarcomatoid component (p=0.029), VEGFA (p=0.037), and PD-L1 (p=0.001) overexpression, the only factor that remained independently associated (p<0.001) after logistic regression. No difference was observed in clinical outcomes.
CONCLUSION: This study is the first to analyse c-MET status in metastatic ccRCC. The high expression of c-MET in the majority of ccRCC and its independent association with PD-L1 expression, may suggest a potential benefit from combining c-MET inhibitors and targeted immunotherapy.
Auteurs, date et publication :
Auteurs Solène-Florence Kammerer-Jacquet , Sarah Medane , Karim Bensalah , Jean-Christophe Bernhard , Mokrane Yacoub , Frantz Dupuis , Alain Ravaud , Grégory Verhoest , Romain Mathieu , Benoit Peyronnet , Angélique Brunot , Brigitte Laguerre , Alexandra Lespagnol , Jean Mosser , Frédéric Dugay , Marc-Antoine Belaud-Rotureau , Nathalie Rioux-Leclercq
Publication : Targeted Oncology
Date : 2017
Volume : 12
Issue : 4
Pages : 487-494
Catégorie(s)
#CNRS #EcoGenO #Université de RennesAuteurs, date et publication :
Auteurs Andrea Bertolo , Marco A. Rodríguez , Gérard Lacroix
Publication : Ecosphere
Date : 2025
Volume : 6
Issue : 11
Pages : art219
Catégorie(s)
#CNRS #ENS #PLANAQUARésumé
The rhizosphere microbiome has been shown to contribute to nutrient acquisition, protection against biotic and abiotic stresses and, ultimately, to changes in the development and physiology of plants. Here, using a controlled natural selection approach, we followed the microbial dynamics in the soil of Arabidopsis thaliana plants infected with the foliar pathogen Pseudomonas syringae DC3000 (Pst).
Auteurs, date et publication :
Auteurs Tetiana Kalachova , Barbora Jindřichová , Lenka Burketová , Cécile Monard , Manuel Blouin , Samuel Jacquiod , Eric Ruelland , Ruben Puga-Freitas
Publication : Plant and Soil
Date : 2022
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Despite considerable efforts devoted to investigate the community assembly processes driving plant invasions, few general conclusions have been drawn so far. Three main processes, generally acting as successive filters, are thought to be of prime importance. The invader has to disperse (1st filter) into a suitable environment (2nd filter) and succeed in establishing in recipient communities through competitive interactions (3rd filter) using two strategies: competition avoidance by the use of different resources (resource opportunity), or competitive exclusion of native species. Surprisingly, despite the general consensus on the importance of investigating these three processes and their interplay, they are usually studied independently. Here we aim to analyse these three filters together, by including them all: abiotic environment, dispersal and biotic interactions, into models of invasive species distributions. We first propose a suite of indices (based on species functional dissimilarities) supposed to reflect the two competitive strategies (resource opportunity and competition exclusion). Then, we use a set of generalised linear models to explain the distribution of seven herbaceous invaders in natural communities (using a large vegetation database for the French Alps containing 5,000 community-plots). Finally, we measure the relative importance of competitive interaction indices, identify the type of coexistence mechanism involved and how this varies along environmental gradients. Adding competition indices significantly improved model’s performance, but neither resource opportunity nor competitive exclusion were common strategies among the seven species. Overall, we show that combining environmental, dispersal and biotic information to model invasions has excellent potential for improving our understanding of invader success.
Auteurs, date et publication :
Auteurs Laure Gallien , Florent Mazel , Sébastien Lavergne , Julien Renaud , Rolland Douzet , Wilfried Thuiller
Publication : Biological Invasions
Date : 2015
Volume : 17
Issue : 5
Pages : 1407-1423
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs N. Legay , C. Baxendale , K. Grigulis , U. Krainer , E. Kastl , M. Schloter , R. D. Bardgett , C. Arnoldi , M. Bahn , M. Dumont , F. Poly , T. Pommier , J. C. Clément , S. Lavorel
Publication : Annals of Botany
Date : 2014
Volume : 114
Issue : 5
Pages : 1011-1021
Catégorie(s)
#CNRS #Lautaret #UGARésumé
Background: The advent of molecular techniques in microbial ecology has aroused interest in gaining an understanding about the spatial distribution of regional pools of soil microbes and the main drivers responsible of these spatial patterns. Here, we assessed the distribution of crenarcheal, bacterial and fungal communities in an alpine landscape displaying high turnover in plant species over short distances. Our aim is to determine the relative contribution of plant species composition, environmental conditions, and geographic isolation on microbial community distribution.
Methodology/Principal Findings: Eleven types of habitats that best represent the landscape heterogeneity were investigated. Crenarchaeal, bacterial and fungal communities were described by means of Single Strand Conformation Polymorphism. Relationships between microbial beta diversity patterns were examined by using Bray-Curtis dissimilarities and Principal Coordinate Analyses. Distance-based redundancy analyses and variation partitioning were used to estimate the relative contributions of different drivers on microbial beta diversity. Microbial communities tended to be habitatspecific and did not display significant spatial autocorrelation. Microbial beta diversity correlated with soil pH. Fungal betadiversity was mainly related to soil organic matter. Though the effect of plant species composition was significant for all microbial groups, it was much stronger for Fungi. In contrast, geographic distances did not have any effect on microbial beta diversity.
Conclusions/Significance: Microbial communities exhibit non-random spatial patterns of diversity in alpine landscapes. Crenarcheal, bacterial and fungal community turnover is high and associated with plant species composition through different set of soil variables, but is not caused by geographical isolation.
Auteurs, date et publication :
Auteurs Lucie Zinger , David P. H. Lejon , Florence Baptist , Abderrahim Bouasria , Serge Aubert , Roberto A. Geremia , Philippe Choler , Jack Anthony Gilbert
Publication : Plos One
Date : 2011
Volume : 6
Issue : 5
Pages : e19950