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Obesity increases DNA damage in the breast epithelium
No full textInternational audienceObesity is a modifiable risk factor for breast cancer. Yet, how obesity contributes to cancer initiation is not fully understood. The goal of this study was to determine if the body mass index (BMI) and metabolic hallmarks of obesity are related to DNA damage in normal breast tissue. In a mouse model of diet-induced obesity, weight gain was associated with elevated levels of DNA double-strand breaks in the mammary gland. We also found a positive correlation between BMI and DNA breaks in the breast epithelium of premenopausal women (but not postmenopausal women). High BMI was associated with elevated systemic and tissue-level oxidative DNA damage across the lifespan, and we propose that the breast epithelium undergoing menstruous proliferation waves is particularly prone to the generation of DNA breaks from oxidative lesions. Ancestry was an important modulator of the obesity-DNA break connection. Compared to non-Hispanic Whites, women identifying as African Americans had higher levels of DNA breaks, as well as elevated leptin and IGF-1. In 3D cultures of breast acini, both leptin and IGF-1 caused an accumulation of DNA damage. The results highlight a connection between premalignant genomic alterations in the breast epithelium and metabolic health modulated by obesity and ancestry. They call for attention on biological determinants of breast cancer risk disparities
Litter in French urban areas — Part 2: transport dynamic and fluxes in stormwater
No full textInternational audienceUrban areas constitute a major hotspot of litter, including plastic litter, that stormwater can wash off towards waterways. However, few studies quantified and characterized litter densities in urban areas and fluxes transported by stormwater networks. Moreover, little information is available on litter transport dynamics in stormwater, and on the factors driving this transport. This study aims at characterizing and quantifying litter amounts transported by stormwater of two nested French urban catchments (total surface area of 105 ha). Litter densities relative to land uses and rain events were investigated in the same catchments as in a compagnon paper (Ledieu et al., 2024). The present study explores the impact of rain events on the transport of urban litter in stormwater. Litter collection and characterization combined with a capture/recapture experiment using tagged litter placed in stormwater inlets show total litter fluxes of 29 kg/year, in which 14 kg/year are plastics, exported at the stormwater outlet. These fluxes confirm that stormwater runoff is a considerable pathway from urban surfaces to waterways, especially regarding small plastic litter (< 2.5 cm). Item transport dynamic is however not linear and only 0.3% of the urban litter appear remobilized. Litter transport dynamics depends on several factors (urban litter densities, hydrometeorological parameters, item composition and morphologies, and stormwater management systems) that should be considered in global models
HILBERT 17TH PROPERTY AND CENTRAL ORDERINGS
No full textInternational audienceThis paper is dedicated to the study of the converse implication in Hilbert 17th problem for a general commutative ring. In this direction, we introduce the notions of central and precentral orderings which generalize the notion of central points of irreducible real algebraic varieties. We study these two families of orderings which both live in the real spectrum of the ring and allow to state new Positivstellensätze and to obtain an equivalence in Hilbert 17th problem
Interfacial Tensions and Critical Surface Tensions of Stainless Steels in a Dense CO2 Atmosphere
No full textInternational audienceInterfacial properties of stainless steel/CO₂ systems are critical to several emerging applications, including geological carbon sequestration, enhanced oil recovery, and the development of supercritical CO₂ processes. However, these interfaces have been rarely investigated, particularly under high-pressure and high-temperature conditions. This study aims to determine the critical surface tension (γC) and interfacial tension (γSF) at the stainless steel/CO₂ interface. Hence, γC and γSF were determined using Zisman plots and Good's theory, respectively, with the latter requiring the calculation of a molecular interaction parameter. Measurements were carried out on two stainless steels (316 and 316L) in a dense CO₂ atmosphere. The experimental conditions covered pressures from 0.1 MPa to 15.1 MPa and temperatures of 313 K and 333 K, representative of the aforementioned applications. Both γC and γSF decreased with increasing pressure, while the influence of temperature exhibited more complex trends. This study highlights a correlation between interfacial properties and the thermodynamic state of CO₂, as described by the Widom line, which marks the transition between gas-like and liquid-like regimes in supercritical fluids. Finally, the results show similar values for 316 and 316L, in good agreement with a previous study conducted on 303 stainless steel, supporting the hypothesis that average values can be extended to austenitic stainless steels in general
Liver fibrosis evaluation in patients with psychiatric diseases
No full textInternational audienceIntroduction: Mental illnesses and psychiatric disorders are public health problems, with an increasing prevalence. Life expectancy of patients is compromised by comorbid somatic illnesses, including liver diseases. Screening for liver fibrosis in this population is challenging.Materials & Methods: We assessed liver fibrosis using liver stiffness (LS) measurement by FibroScan® in a large cohort of patients with severe psychiatric disorders receiving psychotropic medications for at least two years. Liver steatosis was evaluated using the Controlled Attenuation Parameter™ (CAP).Results: 355 patients were prospectively included. Advanced fibrosis (LS >8 kPa) prevalence was 6 %. In univariate analysis, advanced fibrosis was associated with high blood pressure (p < 0.001), high ferritin concentration (p = 0.028), and psychotropic drug exposure (p = 0.036). In multivariate analysis, high blood pressure only remained significant (p = 0.002). 34.9 % of patients had significant steatosis (CAP >275 dB/m). In univariate analysis, steatosis was associated with sleep apnea syndrome (p = 0.016), past alcohol dependence (p = 0.013), high body mass index (BMI), type 2 diabetes (p = 0.003), elevated triglycerides (p < 0.001), metabolic syndrome (p < 0.001), metabolic dysfunction-associated liver disease (p < 0.001), and high ferritin concentration (p = 0.008). In multivariable analysis, high BMI and elevated triglycerides remained significant.Conclusion: Psychiatric patients are at risk of liver fibrosis and steatosis. Systematic screening for liver diseases should be required. Further studies are needed to determine the best strategies for prevention and treatment
P-1032. Posaconazole for Prevention of COVID-19 Associated Pulmonary Aspergillosis in Mechanically Ventilated Patients: the POSACOVID Study
No full textIDWeek 2024International audienc
Des forêts classées aux paysages du patrimoine mondial. L’héritage forestier colonial dans la patrimonialisation contemporaine des paysages de savane en Afrique de l’Ouest
No full textInternational audienceThis article analyses how protected areas in West Africa originated and evolved, and more specifically those in savanna environments. It takes a cross-disciplinary approach combining scientific literature, historical sources, cartographic data and field surveys conducted between 2023 and 2024 in the Kédougou region of Senegal. The study highlights the colonial origins of early environmental protection policies which were centred on a utilitarian and naturalistic view of landscapes. The use of the landscape as a tool for heritage preservation in the context of the Bassari, Fula and Bedik cultural landscapes which are on the UNESCO World Heritage List is intended to break with a naturalistic view by integrating a social dimension into conservation approaches. However, this stated desire to recognise local practices is ambiguous. Heritage designation continues to be largely guided by international standards and a naturalistic approach often disconnected from local agricultural, forest farming or pastoral practices. The article examines the tensions between an institutional recognition of the role of societies in the creation of landscapes and an inherited view that limits recognition of this role when defining management and conservation policies.Cet article propose une analyse de la genèse et des évolutions des aires protégées en Afrique de l’Ouest, en particulier dans le contexte des savanes soudaniennes. Il s’appuie sur une approche croisée, combinant littérature scientifique, sources historiques, données cartographiques et enquêtes de terrain menées entre 2023 et 2024 dans la région de Kédougou, au Sénégal. L’étude met en évidence l’ancrage colonial des premières politiques de protection environnementale, centrées sur une vision utilitariste et naturaliste des paysages. Le recours au paysage comme outil de patrimonialisation, dans le cadre du Pays Bassari : paysages culturels Bassari, Peul et Bédik sur la liste du patrimoine mondial de l’Unesco, se veut en rupture avec une vision naturaliste, en intégrant aux logiques de conservation une dimension sociale. Cependant, cette volonté affichée de reconnaître les pratiques locales demeure ambiguë. La patrimonialisation reste largement guidée par des normes internationales et une logique naturaliste, souvent déconnectée des pratiques agro-sylvo-pastorales locales. L’article s’interroge ainsi sur les tensions entre la reconnaissance institutionnelle du rôle des sociétés dans la fabrique des paysages et le poids d’une vision héritée, qui limite leur prise en compte dans les politiques de gestion et de conservation
Recent aqueous alteration associated to sedimentary volcanism on Mars
No full textInternational audienceSedimentary volcanism, whereby material is brought to the surface by fluid overpressure, has been proposed to explain some of the periglacial landforms, including pitted cones, in the Northern Plains of Mars. However, in the absence of convincing mineralogical evidence, the origin for these deposits has never been conclusively determined. Here we conduct a remote sensing-based mineralogical survey to identify hydrated minerals within the Thumbprint Terrains and neighbouring Vastitas Borealis Formation. We detect several occurrences of hydrated silica along with sulfate salts in candidate mud volcano-like morphologies which likely formed during the Early Amazonian period, supporting the sedimentary volcanism origin. Buoyancy-driven analytical modelling suggests the hydrated silica and sulfate salts are sourced from reservoirs at depths of several 10 s and 100 s of metres, respectively below the Thumbprint Terrains and Vastitas Borealis Formation. The exposed sulfates may have been derived from ancient buried evaporite deposits suggesting, at least locally, a salt-rich aqueous origin for the Vastitas Borealis Formation, and would be consistent with the presence of a past northern ocean on Mars.</div
Reimagining Urban River Bathing in Europe: A Multisectoral and Interdisciplinary Dive Into Lyon's Rivers (France)
No full textInternational audienceUrban river bathing is re‐emerging across Europe, driven by social demand and climate change impacts. The Urban Bathing Consortium, an interdisciplinary and intersectoral consortium initiated at the University of Lyon (France), is at the forefront of studying the challenges and opportunities of creating and managing healthy, safe, and accessible river bathing spaces. Through interdisciplinary collaboration among researchers and stakeholders, the consortium proposed an analytical framework, identifying seven critical dimensions for urban river bathing: the history and revival of city‐river relationships, legal and regulatory frameworks, bathing water quality, river drowning risks, river ecosystems, social perspectives, and urban planning. By examining these dimensions with state‐of‐the‐art approaches and drawing on Lyon's experiences, the study provides scientific insights and practical recommendations for future sustainable urban river bathing development. These include revitalizing historical city‐river connections, aligning local regulations with EU guidance, advancing holistic microbial water quality control, enhancing safety measures, incorporating ecological considerations, balancing competing river uses in urban planning, and addressing social needs for inclusive river governance
Synthetic Community Inoculation on Seeds Revealed its Transient Colonization Capacity but Legacy Effects on Plant Microbiota Assembly
No full textAbstract Seed microbiota have the potential to influence the overall plant microbiota assembly. However, to date, studies have mostly focused on early plant development stages. This study aimed to investigate the influence of seed microbiota on plant microbiota assembly throughout an entire life cycle. To achieve this, bacterial synthetic communities (SynComs) were reconstructed and inoculated on common bean seeds to eliminate the natural variability of seed microbiota and provide four different primary inocula for comparison. We then examined bacterial and fungal communities at different developmental stages (seedling, vegetative, flowering, pod-filling, and senescent stages) and in different plant compartments (rhizosphere, root, leaf, seed) of the common bean. SynComs inoculated on seeds significantly contributed to the seedling microbiota, with higher colonization success in the leaves compared to roots and rhizospheres. Strain identity and SynCom composition influenced the strain colonization capacity across the habitats. Also, bacterial SynCom colonization induced composition modification in the seedling root and leaf microbiota. After the seedling stage, SynComs members were not detected in plant compartments but promoted persistent changes in microbial community composition until the next generation of seeds. In conclusion, SynCom inoculated on seeds have a transient colonization that can influence the overall plant microbiota assembly through priority effects