Physico-chemical properties and toxicological effects on plant and algal models of carbon nanosheets from a nettle fibre clone.

peer reviewedCarbon nanosheets are two-dimensional nanostructured materials that have applications as energy storage devices, electrochemical sensors, sample supports, filtration membranes, thanks to their high porosity and surface area. Here, for the first time, carbon nanosheets have been prepared from the stems and leaves of a nettle fibre clone, by using a cheap and straight-forward procedure that can be easily scaled up. The nanomaterial shows interesting physical parameters, namely interconnectivity of pores, graphitization, surface area and pore width. These characteristics are similar to those described for the nanomaterials obtained from other fibre crops. However, the advantage of nettle over other plants is its fast growth and easy propagation of homogeneous material using stem cuttings. This last aspect guarantees homogeneity of the starting raw material, a feature that is sought-after to get a nanomaterial with homogeneous and reproducible properties. To evaluate the potential toxic effects if released in the environment, an assessment of the impact on plant reproduction performance and microalgal growth has been carried out by using tobacco pollen cells and the green microalga Pseudokirchneriella subcapitata. No inhibitory effects on pollen germination are recorded, while algal growth inhibition is observed at higher concentrations of leaf carbon nanosheets with lower graphitization degree

Increased KL-6 levels in moderate to severe COVID-19 infection.

peer reviewed[en] BACKGROUND: The global coronavirus disease 2019 (COVID-19) has presented significant challenges and created concerns worldwide. Besides, patients who have experienced a SARS-CoV-2 infection could present post-viral complications that can ultimately lead to pulmonary fibrosis. Serum levels of Krebs von den Lungen 6 (KL-6), high molecular weight human MUC1 mucin, are increased in the most patients with various interstitial lung damage. Since its production is raised during epithelial damages, KL-6 could be a helpful non-invasive marker to monitor COVID-19 infection and predict post-infection sequelae. METHODS: We retrospectively evaluated KL-6 levels of 222 COVID-19 infected patients and 70 healthy control. Serum KL-6, fibrinogen, lactate dehydrogenase (LDH), platelet-lymphocytes ratio (PLR) levels and other biological parameters were analyzed. This retrospective study also characterized the relationships between serum KL-6 levels and pulmonary function variables. RESULTS: Our results showed that serum KL-6 levels in COVID-19 patients were increased compared to healthy subjects (470 U/ml vs 254 U/ml, P 453.5 U/ml was associated with COVID-19 (AUC = 0.8415, P < 0.0001). KL-6 level was positively correlated with other indicators of disease severity such as fibrinogen level (r = 0.1475, P = 0.0287), LDH level (r = 0,31, P = 0,004) and PLR level (r = 0.23, P = 0.0005). However, KL-6 levels were not correlated with pulmonary function tests (r = 0.04, P = 0.69). CONCLUSIONS: KL-6 expression was correlated with several disease severity indicators. However, the association between mortality and long-term follow-up outcomes needs further investigation. More extensive trials are required to prove that KL-6 could be a marker of disease severity in COVID-19 infection

Impact d'une contamination au méthylmercure par voie alimentaire sur l'expression génétique, la bioénergétique, et la reproduction chez le poisson zèbre Danio rerio

Les effets de la contamination au méthylmercure chez le poisson zèbre Danio rerio ont été interrogés au sein de deux tissus, le muscle squelettique et le système nerveux central, dont le choix fut motivé par leur fort potentiel bioaccumulateur de cet organométallique. Après contamination par voie trophique, à un niveau d’exposition représentatif de ce qui peut advenir dans certains écosystèmes aquatiques, nos observations expérimentales indiquent que ce métal perturbe fortement le métabolisme mitochondrial dans les muscles, mais épargne celui du cerveau ; en outre, l’analyse de l’expression génique suggère une perturbation de l’homéostasie du calcium dans ces deux tissus. Dans le système nerveux central, parmi les synapses glutamatergique et GABAnergique, seule la voie métabolique du GABA semble montrer une adaptation face au MeHg. Concernant le muscle squelettique, l’analyse SAGE a permis d’appréhender les impacts du MeHg à l’échelle cellulaire, révélant également une perturbation de la synthèse protéique, l’induction d’un stress au niveau du reticulum endoplasmique ainsi que l’induction de plusieurs gènes impliqués dans les processus de détoxication et les voies de réponse générale au stress. Notre étude a également mis en évidence la surexpression du gène de la vitellogénine dans le muscle chez des poissons mâles désignant ainsi ce métal comme un perturbateur endocrinien. Enfin, nous avons également révélé une perturbation importante de l’éclosion des œufs associée à un transfert maternel de ce toxique.The effects of methylmercury contamination on the zebrafish, Danio rerio, were assessed in two tissues, the skeletal muscle and the central nervous system, whose choice was motivated by their high potential to bioaccumulate this organometallic. After contamination by dietary, at a representative exposure level of which may arise in some aquatic ecosystems, our experimental observations indicate that metal strongly disrupts the mitochondrial metabolism in the muscles, but savings that the brain; in addition, the gene expression analysis suggests a disruption of the calcium homeostasis in these two tissues. In the central nervous system among glutamatergique and GABAnergique synapses, only the metabolic pathway of the GABA seems to show an adaptation to the MeHg. Concerning the skeletal muscle scanning SAGE analysis helped to understand the impacts of the MeHg at the cellular scale. It is also revealing a disruption of the protein synthesis, the induction of a stress at the endoplasmic reticulum level as well as the induction of several genes involved in detoxification process and general stress response. Our study has also highlighted the induction of the vitellogenin gene in the muscle of male fish designating this metal as an endocrine disruptor. Finally, we have also revealed a significant disruption of hatching eggs associated with maternal transfer of this toxic

Impact d'une contamination au méthylmercure par voie alimentaire sur l'expression génétique, la bioénergétique, et la reproduction chez le poisson zèbre Danio rerio

Les effets de la contamination au méthylmercure chez le poisson zèbre Danio rerio ont été interrogés au sein de deux tissus, le muscle squelettique et le système nerveux central, dont le choix fut motivé par leur fort potentiel bioaccumulateur de cet organométallique. Après contamination par voie trophique, à un niveau d’exposition représentatif de ce qui peut advenir dans certains écosystèmes aquatiques, nos observations expérimentales indiquent que ce métal perturbe fortement le métabolisme mitochondrial dans les muscles, mais épargne celui du cerveau ; en outre, l’analyse de l’expression génique suggère une perturbation de l’homéostasie du calcium dans ces deux tissus. Dans le système nerveux central, parmi les synapses glutamatergique et GABAnergique, seule la voie métabolique du GABA semble montrer une adaptation face au MeHg. Concernant le muscle squelettique, l’analyse SAGE a permis d’appréhender les impacts du MeHg à l’échelle cellulaire, révélant également une perturbation de la synthèse protéique, l’induction d’un stress au niveau du reticulum endoplasmique ainsi que l’induction de plusieurs gènes impliqués dans les processus de détoxication et les voies de réponse générale au stress. Notre étude a également mis en évidence la surexpression du gène de la vitellogénine dans le muscle chez des poissons mâles désignant ainsi ce métal comme un perturbateur endocrinien. Enfin, nous avons également révélé une perturbation importante de l’éclosion des œufs associée à un transfert maternel de ce toxique.The effects of methylmercury contamination on the zebrafish, Danio rerio, were assessed in two tissues, the skeletal muscle and the central nervous system, whose choice was motivated by their high potential to bioaccumulate this organometallic. After contamination by dietary, at a representative exposure level of which may arise in some aquatic ecosystems, our experimental observations indicate that metal strongly disrupts the mitochondrial metabolism in the muscles, but savings that the brain; in addition, the gene expression analysis suggests a disruption of the calcium homeostasis in these two tissues. In the central nervous system among glutamatergique and GABAnergique synapses, only the metabolic pathway of the GABA seems to show an adaptation to the MeHg. Concerning the skeletal muscle scanning SAGE analysis helped to understand the impacts of the MeHg at the cellular scale. It is also revealing a disruption of the protein synthesis, the induction of a stress at the endoplasmic reticulum level as well as the induction of several genes involved in detoxification process and general stress response. Our study has also highlighted the induction of the vitellogenin gene in the muscle of male fish designating this metal as an endocrine disruptor. Finally, we have also revealed a significant disruption of hatching eggs associated with maternal transfer of this toxic

The Onera elsA CFD software: input from research and feedback from industry

International audienceThe Onera elsA CFD software is both a software package capitalizing the innovative results of research over time and a multi-purpose tool for applied CFD and multi-physics. The research input from Onera and other laboratories and the feedback from aeronautical industry users allow enhancement of its capabilities and continuous improvement. The paper presents recent accomplishments of varying complexity from research and industry for a wide range of aerospace applications: aircraft, helicopters, turbomachinery..

Impact d'une contamination au méthylmercure par voie alimentaire sur l'expression génétique, la bioénergétique, et la reproduction chez le poisson zèbre Danio rerio

Les effets de la contamination au méthylmercure chez le poisson zèbre Danio rerio ont été interrogés au sein de deux tissus, le muscle squelettique et le système nerveux central, dont le choix fut motivé par leur fort potentiel bioaccumulateur de cet organométallique. Après contamination par voie trophique, à un niveau d exposition représentatif de ce qui peut advenir dans certains écosystèmes aquatiques, nos observations expérimentales indiquent que ce métal perturbe fortement le métabolisme mitochondrial dans les muscles, mais épargne celui du cerveau; en outre, l analyse de l expression génique suggère une perturbation de l homéostasie du calcium dans ces deux tissus. Dans le système nerveux central, parmi les synapses glutamatergique et GABAnergique, seule la voie métabolique du GABA semble montrer une adaptation face au MeHg. Concernant le muscle squelettique, l analyse SAGE a permis d appréhender les impacts du MeHg à l échelle cellulaire, révélant également une perturbation de la synthèse protéique, l induction d un stress au niveau du reticulum endoplasmique ainsi que l induction de plusieurs gènes impliqués dans les processus de détoxication et les voies de réponse générale au stress. Notre étude a également mis en évidence la surexpression du gène de la vitellogénine dans le muscle chez des poissons mâles désignant ainsi ce métal comme un perturbateur endocrinien. Enfin, nous avons également révélé une perturbation importante de l éclosion des œufs associée à un transfert maternel de ce toxique.The effects of methylmercury contamination on the zebrafish, Danio rerio, were assessed in two tissues, the skeletal muscle and the central nervous system, whose choice was motivated by their high potential to bioaccumulate this organometallic. After contamination by dietary, at a representative exposure level of which may arise in some aquatic ecosystems, our experimental observations indicate that metal strongly disrupts the mitochondrial metabolism in the muscles, but savings that the brain; in addition, the gene expression analysis suggests a disruption of the calcium homeostasis in these two tissues. In the central nervous system among glutamatergique and GABAnergique synapses, only the metabolic pathway of the GABA seems to show an adaptation to the MeHg. Concerning the skeletal muscle scanning SAGE analysis helped to understand the impacts of the MeHg at the cellular scale. It is also revealing a disruption of the protein synthesis, the induction of a stress at the endoplasmic reticulum level as well as the induction of several genes involved in detoxification process and general stress response. Our study has also highlighted the induction of the vitellogenin gene in the muscle of male fish designating this metal as an endocrine disruptor. Finally, we have also revealed a significant disruption of hatching eggs associated with maternal transfer of this toxic.BORDEAUX1-Bib.electronique (335229901) / SudocSudocFranceF

Cadmium-induced genotoxicity in zebrafish at environmentally relevant dose

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Towards using a 2D magneto-optical trap to improve a mercury optical latice clock

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Towards using a 2D magneto-optical trap to improve a mercury optical latice clock

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The Food Matrix and the Gastrointestinal Fluids Alter the Features of Silver Nanoparticles.

Silver nanoparticles (AgNPs) are used in the agri-food sector, which can lead to their ingestion. Their interaction with food and their passage through the gastrointestinal tract can alter their properties and influence their fate upon ingestion. Therefore, this study aims at developing an in vitro method to follow the fate of AgNPs in the gastrointestinal tract. After incorporation of AgNPs into a standardized food matrix, a precolonic digestion is simulated and AgNPs are characterized by different techniques. The presence of food influences the AgNPs properties by forming a corona around nanoparticles. Even if the salivary step does not impact significantly the AgNPs, the pH decrease and the digestive enzymes induce the agglomeration of AgNPs during the gastric phase, while the addition of intestinal fluids disintegrates these clusters. AgNPs can thus reach the intestinal cells under nanometric form, although the presence of food and gastrointestinal fluids modifies their properties compared to pristine AgNPs. They can form a corona around the nanoparticles and act as colloidal stabilizer, which can impact the interaction of AgNPs with intestinal epithelium. This study demonstrates the importance of taking the fate of AgNPs in the gastrointestinal tract into account to perform an accurate risk assessment of nanomaterials