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Tour d'horizon du contentieux du travail appliqué à la plaisance maritime, DMF janvier 2023, pp. 11-26
No full textInternational audienceThis article provides an overview of the labour law issues raised by maritime leisure and professional yachting. Classic problems are crossed with new ones such as the articulation of the labour code and the transport code, troubles with maritime employers’ indentity or the evolution of labour relations confronted with the rise of digital platforms putting workers in contact. Topics related to maritime employment contracts are also addressed in a synthetic approach from the perspective of the conflict of laws and jurisdictions. The multifaceted nature of yachting allows to insist on methodological subtleties based on examples drawn from case law and which invite us to carefully consider maritime labour law as applied to this sector of activity
Colinet, S. Transition et accompagnement : quelles applications ? In : Boujut, E. Ridremont, D. Rollin, Z (dir). (2023). Transitions des adolescents et jeunes adultes porteurs d'une maladie chronique et invalidante, Bordeaux : Presses Universitaires de Bordeaux.
No full textInternational audienc
Removal of emerging pollutants with Cyclodextrins-clay composites
No full textIt is recognized that a large variety of the organic compounds contaminating the environment can form inclusion complexes with cyclodextrins resulting in enhanced solubility as mentioned in a recent review on cyclodextrins for environmental biotechnologies [1]. Micelle-clay composites have been used for environmental remediation and for the removal of organic pollutants from water [2-5]. In this research we explore the use of cyclodextrins, known to for inclusion complexes and layers onto negatively charged surfaces when combined with cationic surfactants [6-7], to form a composite with clays using similar protocol to the described for micelle-clay composite preparation by Gonzalez-Perez and Macia [8] for the removal of bacteria from water
Fluorinated vesicle-clay composites for PFAs removal from water
No full textThe use of modified clays for environmental remediation is heavily investigated. Different organic compounds containing fluorine are contaminating the environment and damage human health as well can form complexes with other compounds [1]. Modified clays can be efficient for the removal of ionic and non-ionic contaminants [2]. New bioinspired materials are being developed continuously in order to answer the environmental challenges that nature suffer as a consequence of human activities [3], while water utilities keep optimizing processes and cost and using new technology developed elsewhere [4]. Micelle-clay composites have been used for environmental remediation and for the removal of organic pollutants from water [2,5]. The removal of fluorinated compounds from water and soil is difficult. Fluorocarbons can form self-assembled structures and membranes that are at the same time hydrophobic and lipophobic [6,7]. In this research we investigate the use of hybrid catanionic fluoro-hydrocarbon surfactants, known to form membranous vesicular structures to combine with clays to prepare fluoro-vesicles-clay composites for the removal of fluoro-compounds from water
When Instructions Based on Constructive Controversy Boost Synergy in Online Groups
No full textInternational audienceIn response to the COVID-19 pandemic, an increasing number of people throughout the world participated in remote meetings in online groups using videoconferencing systems. The purpose of this study was to examine the effects on group synergy of a series of instructions based on constructive controversy delivered during online collaboration. After performing a decision-making task individually, 125 participants were randomly assigned to online groups to collaborate and reach a consensus using a videoconferencing system, either in “free discussion” or “instructed discussion” groups. Results revealed that groups with instructions outperformed their best members (strong synergy) at higher rates than groups without instructions. Moreover, participants reported higher epistemic conflict regulation when they received instructions than when they did not. These findings suggest that providing instructions based on constructive controversy during a collaborative task can boost synergy and epistemic conflict regulation in online groups
"Le Théâtre de la socialité : un laboratoire pour la création contemporaine ?"
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Etude des mécanismes moléculaires impliqués dans le dialogue entre les cellules B tumorales de Leucémie Lymphoïde Chronique et leur microenvironnement
No full textThe tumor microenvironment plays an important role in the pathophysiology of chronic lymphocytic leukemia (CLL) as it promotes the survival and proliferation of malignant B cells either through direct cell-cell interactions or indirectly through soluble factors. In this study, we focused our attention on β-catenin as an effector of the cross-talk between CLL cells and the microenvironment using a co-culture model of tumor cells with a human bone marrow stromal cell line, HS-5. β-catenin is a known regulator of cell adhesion but it also behaves as a transcriptional co-activator in several signal transduction cascades induced by different stimuli, including Wnt and the BCR. When CLL and HS-5 cells are co-cultured, a fraction of CLL cells adhere to HS-5 whereas another fraction remain in suspension. We observed that the amount and distribution of β-catenin varies in the adherent versus suspension cells, suggesting a different role of β-catenin in these two cell fractions. Indeed, we observed that in suspension cells, β-catenin is stabilized, interacts with the kinase BTK and, regulates Cyclin D1 gene transcription. However, in adherent cells β-catenin is mainly in the cytosol/membrane compartments. When β-catenin is overexpressed in CLL cells, their adhesion to stromal cells is exacerbated without consequences on cell migration. Thesedata indicate that β-catenin, in association with BTK, plays a role in regulating the dialogue between tumor cells and their microenvironment. In the second part of this project, we analyzed the effect of CLL cells on the phenotypic and functional reprogramming of HS-5 cells. Our results suggest that CLL cells promote tumor immune evasion by secreting immunomodulatory cytokines (IFNγ, TNFα) to direct HS-5 cells to a FRC-like lymph node cell lineage. A better understanding of the mechanisms by which tumor cells increase their survival and escape immune surveillance could open new therapeutic avenues to block the harmful dialogue between leukemic cells and their microenvironment and restore effective immunity at sites of tumor proliferation.Le microenvironnement tumoral joue un rôle majeur dans la physiopathologie de la leucémie lymphoïde chronique (LLC) car il contribue à la survie et la prolifération des cellules B malignes par l’intermédiaire d’interactions directes intercellulaires ou indirectes via des facteurs solubles. Dans le cadre de l’étude du dialogue entre les cellules LLC et leur microenvironnement, nous avons porté notre attention sur la β-caténine pour sa capacité à réguler l’adhérence cellulaire mais également à induire une réponse transcriptionnelle de gènes pro-survie. La co-culture de cellules LLC (primaires ou lignées) avec des cellules stromales (la lignée HS-5) constitue un modèle de choix pour mimer les échanges avec le microenvironnement. Lors de leur co-culture, les cellules LLC se répartissent en deux fractions : une fraction adhérente et une fraction non adhérente aux cellules stromales. Dans les cellules LLC non-adhérentes, la β-caténine est fortement stabilisée, interagit avec la kinase BTK et régule la transcription du gène Cyclin D1. En revanche, cette stabilisation n’est pas observée dans les cellules adhérentes et la β-caténine est localisée à la membrane cellulaire. La surexpression dans les cellules LLC de la β-caténine augmente leur adhérence aux cellules stromales. Ces données indiquent que la β-caténine, en association avec BTK, joue un rôle de régulateur du dialogue entre les cellules tumorales et leur microenvironnement. Dans une deuxième partie, nous avons analysé l’impact des cellules LLC sur la reprogrammation phénotypique et fonctionnelle des cellules HS-5. Nos résultats montrent que les cellules LLC orientent les cellules HS-5 vers un profil de cellules ganglionnaires de type FRC via notamment la sécrétion de cytokines immunomodulatrices (IFNβγ, TNFα), favorisant ainsi l’échappement immunitaire de la tumeur. La description à l’échelle moléculaire du dialogue entre la cellule tumorale et son microenvironnement permettra de mieux comprendre la physiopathologie de la LLC mais également de mettre en évidence des cibles thérapeutiques alternatives aux stratégies actuelles afin de cibler et de bloquer le dialogue délétère que la tumeur établit avec son microenvironnement
Influence of temperature on regulation of key virulence and stress response genes in Listeria monocytogenes biofilms
No full textInternational audienceTemperature is a major determinant of Listeria (L.) monocytogenes adherence and biofilm formation on abiotic surfaces. However, its role on gene regulation of L. monocytogenes mature biofilms has not been investigated. In the present study, we aimed to evaluate the impact of temperature up-and down-shift on L. monocytogenes biofilms gene transcription. L. monocytogenes strain EGD-e biofilms were first developed on stainless steel surfaces in Brain Heart Infusion broth at 20 • C for 48 h. Then, nutrient broth was renewed, and mature biofilms were exposed to 10 • C, 20 • C or 37 • C for 24 h. Biofilm cells were harvested and RNA levels of plcA, prfA, hly, mpl, plcB, sigB, bapL, fbpA, fbpB, lmo2178, lmo0880, lmo0160, lmo1115, lmo 2089, lmo2576, lmo0159 and lmo0627 were evaluated by quantitative RT-PCR. The results revealed an over-expression of all genes tested in biofilm cells compared to planktonic cells. When biofilms were further allowed to proliferate at 20 • C for 24 h, the transcription levels of key virulence, stress response and putative binding proteins genes plcA, sigB, fbpA, fbpB, lmo1115, lmo0880 and lmo2089 decreased. A temperature-dependent transcription for sigB, plcA, hly, and lmo2089 genes was observed after biofilm proliferation at 10 • C or 37 • C. Our findings suggest that temperature differentially affects gene regulation of L. monocytogenes mature biofilms, thus modulating attributes such as virulence, stress response and pathogenesis
Utilization patterns, cardiovascular risk, and concomitant serotoninergic medications among triptan users between 2008 and 2018: A gender analysis in one Italian region, Tuscany
No full textInternational audienceOBJECTIVE: To describe the pattern of triptan use by gender in Tuscany, Italy, focusing on special user populations in which evidence on triptan safety is still not conclusive. BACKGROUND: Growing evidence supports the role of gender differences in migraine pathophysiology and treatment. However, gender impact on triptan real-word utilization has been poorly investigated. METHODS: A retrospective, descriptive, cohort study was performed using the population-based Administrative Healthcare Database of Tuscany region (Italy). Subjects registered in the database on the January 1 of each year between 2008 and 2018 were identified. New users (NU) of triptans (ATC:N02CC*) were patients with one or more triptan dispensation during the year of interest and none in the past. Age, cardiovascular comorbidities representing an absolute or a possible contraindication to triptan utilization, concomitant serotonergic medications, and pattern of triptan use during 1-year follow-up were described by gender. RESULTS: A total of 86,109 patients who received one or more triptan dispensing were identified. Of 64,672 NU (men = 17,039; women = 47,633), 10.2% (6823/64,672) were aged >65 years, who were mostly women (n = 4613). Among NU, men and women with absolute cardiovascular contraindications were 4.3% (740/17,039) and 2.1% (1022/47,633), respectively, while those concomitantly taking serotonergic medications were 17.2% (267/1549) and 21.9% (949/4330), respectively (949/4330). Regular users (two or more dispensing with ≥3 months between first and last observed dispensing) accounted for 26.4% of women (12,597/47,633) and 19.11% of men (3250/17,039); frequent users (≥15 dosage units/month during ≥3 consecutive months) were overall 0.1% (94/64,672) and 62.0% (58/94) of them concomitantly received serotonergic medications. CONCLUSION: Considering gender differences in triptan use highlighted here, large scale observational studies are warranted to better define what populations are safe to use triptans and whether it is appropriate to tighten or relax certain recommendations on triptan use. In the meantime, any suspected adverse drug reaction observed in the special user populations highlighted in this study should be promptly reported