The twin-screw extrusion technology, an original solution for the extraction of proteins from sunflower and alfalfa

Twin-screw extrusion has been used for the protein extraction from sunflower and alfalfa. Thermo-mechanical fractionation and aqueous extraction are conducted simultaneously to collect separately a liquid extract and a solid raffinate. From sunflower whole plant, squeezing in the reversed screws is favored by the fibers abundance in the stalk, and it enables L/S separation. Protein yield is 44%, in the best conditions, and lipids are partly co-extracted. Water-soluble proteins are in an aqueous extract and in two O/W emulsions due to their surface-active properties. Hence, the oil is co-extracted in the form of emulsions stabilized by proteins at interface. Proteins can be collected in the aqueous extract by isoelectric precipitation. Emulsions are usable for oil production. Their demulsification with ethanol produces a precipitate rich in proteins with low denaturation level. From alfalfa whole plant, the highest protein yield in the aqueous extract (called green juice) is 25% when water is added in the extruder. Water-soluble and water-insoluble green juice proteins can be fractionated thanks to L/L extraction in sunflower oil and ammonium sulfate precipitation. Some other molecules are co-extracted (polysaccharides, phenolic compounds). They can be purified with ultrafiltration or chromatography

CD9 Tetraspanin: A New Pathway for the Regulation of Inflammation?

CD9 belongs to the tetraspanin superfamily. Depending on the cell type and associated molecules, CD9 has a wide variety of biological activities such as cell adhesion, motility, metastasis, growth, signal transduction, differentiation, and sperm–egg fusion. This review focuses on CD9 expression by hematopoietic cells and its role in modulating cellular processes involved in the regulation of inflammation. CD9 is functionally very important in many diseases and is involved either in the regulation or in the mediation of the disease. The role of CD9 in various diseases, such as viral and bacterial infections, cancer and chronic lung allograft dysfunction, is discussed. This review focuses also on its interest as a biomarker in diseases. Indeed CD9 is primarily known as a specific exosome marker however, its expression is now recognized as an anti-inflammatory marker of monocytes and macrophages. It was also described as a marker of murine IL-10-competent Breg cells and IL-10-secreting CD9+ B cells were associated with better allograft outcome in lung transplant patients, and identified as a new predictive biomarker of long-term survival. In the field of cancer, CD9 was both identified as a favorable prognostic marker or as a predictor of metastatic potential depending on cancer types. Finally, this review discusses strategies to target CD9 as a therapeutic tool. Because CD9 can have opposite effects depending on the situation, the environment and the pathology, modulating CD9 expression or blocking its effects seem to be a new promising therapeutic strategy

Étude de la bioraffinerie des plantes vertes (Application au fractionnement des protéines de luzerne par extrusion bi-vis et chromatographie hydrophobe)

La luzerne est une plante fourragère, de la famille des Fabacées, largement cultivée en France du fait de sa richesse en protéines. Industriellement, cette plante est pressée, puis séchée sur tambour rotatif. L étape de pressage conduit à l obtention de grandes quantités de jus, lui aussi riche en protéines. L objectif de cette thèse a été de développer un procédé de bioraffinerie de la luzerne, applicable aux autres plantes fourragères, permettant la valorisation des toutes les fractions de la plante. La première étape consiste en un fractionnement thermo-mécanique de la luzerne entière par extrusion bi-vis. Deux fractions sont obtenues : un résidu fibreux solide en partie déshydraté, pouvant être utilisé dans la filière agro-matériaux, et un filtrat vert, riche en protéines. L extrusion bi-vis est une alternative intéressante aux procédés classiques de déshydratation, car l étude de l optimisation des paramètres d extrusion a permis de montrer qu il est possible de récupérer la grande majorité des protéines de la plante dans le filtrat. Ce filtrat subit par la suite une séparation liquide/solide par centrifugation, permettant la récupération d un culot vert, dont on peut extraire la chlorophylle. Le jus clarifié est ultrafiltré, puis traité par chromatographie hydrophobe, avec l huile de tournesol comme solvant extracteur, de manière à séparer différentes protéines. L étude plus fondamentale de la fixation des protéines sur résine a permis de modéliser le fractionnement des protéines par interactions hydrophobes.Alfalfa is a common Legume, cultivated as a forage crop, thanks to its high protein content. In the green crop industry, alfalfa is pressed and dried on a rotative cylinder. The pressing step leads to the production of large amounts of green juice, rich in proteins. The aim of this work was to develop a biorefinery process for alfalfa, which could be adapted to other green crops, allowing the valorization of each fraction. The first step is the whole plant thermo-mechanical fractionation in the twin-screw extruder. Two fractions are obtained: a solid fibrous residue, partly dehydrated which could be valorized as an agro-material, and a green filtrate, rich in proteins. Twin-screw extrusion is an interesting alternative to usual industrial dehydration processes. Indeed, the study of the extruder parameters optimization showed that most of the alfalfa proteins can be recovered in the filtrate. This green extract is then centrifuged, in order to separate the solid particles. Chlorophyll can be extracted from the centrifugation pellet. The clarified juice is treated by ultrafiltration, and lastly fractionated thanks to hydrophobic chromatography, with sunflower oil as the solvent, in order to separate the proteins. The more fundamental study of proteins fixation on resins allowed us to modelize proteins fractionation using hydrophobic interactions.TOULOUSE-INP (315552154) / SudocSudocFranceF

Inferring site function and technological organization from combined spatial, technological and microwear-analyses at the Mesolithic wetland site of Kerkhove-Stuw, northwestern Belgium (preliminary results)

The extensive Mesolithic site of Kerkhove-Stuw was located on the top of a natural levee,adjacent to a palaeochannel of the river Scheldt. Subsequently (from the boreal onwards),the landscape was covered by approximately 4,5m to 9m of peat and alluvial clay. The infillof the palaeochannel deposits were studied by means of a high-resolution multi-proxy analysis(i.e. pollen, microcharcoal, loss on ignition, magnetic susceptibility, granulometry, molluscfauna ...etc.) to reconstruct the varying ecological settings of the prehistoric occupation.The excavations yielded thirteen spatially distinct concentrations of lithic artefacts thatcould be dated to the Early, the Middle and the Late Mesolithic, based on typology. Thiswas partly confirmed by 14C-dates on single entity charred hazelnut shells. Additionally,the site had great potential for a comprehensive technological analysis thanks to the overalllow-density of the lithic concentrations and the diversity of macroscopically discernable rawmaterial categories.Besides lithics, a considerable amount of unburnt and burnt bone fragments, and palaeob-otanical remains were documented. The preservation of a faunal assemblage (dominated byroe deer and wild boar, but also comprised of fur animals and fish remains) is exceptionalfor the Early and Middle Mesolithic in the region and will allow us, for the first time, to gaina better understanding of Mesolithic subsistence practices.Finally, to determine the inter- and intrasite functional properties and aspects of the tech-nological organization of the thirteen lithic concentrations, the spatial distribution of thedifferent types of material remains are studied, combined with a technological and microwearanalysis of the lithic artefacts. For example, the location of ten possible surface hearths couldbe derived from heavily burnt lithic artefacts and burnt organic remains. So far, preliminary results from the technological analysis indicate the presence of several expedient technolo-gies, more elaborate opposed striking platform knapping sequences and a possible diachronicevolution in preferential raw material use. Both spatial analyses and lithic technology arereinforced by an extensive microwear analysis that can specify the objectives of the knappingsequences and mostly the spatial organization of the different activities (butchery, hide andplant scraping, osseous tools manufacturing...) for each occupation phase.In the future, the results from Kerkhove will have to be compared with those previouslyobtained with the same protocol from other (dryland) sites in northwestern Belgium

CD9+ Regulatory B Cells Induce T Cell Apoptosis via IL-10 and Are Reduced in Severe Asthmatic Patients

CD9 was recently identified as a marker of murine IL-10-competent regulatory B cells. Functional impairments or defects in CD9+ IL-10-secreting regulatory B cells are associated with enhanced asthma-like inflammation and airway hyperresponsiveness. In mouse models, all asthma-related features can be abrogated by CD9+ B cell adoptive transfer. We aimed herein to decipher the profiles, features, and molecular mechanisms of the regulatory properties of CD9+ B cells in human and mouse. The profile of CD9+ B cells was analyzed using blood from severe asthmatic patients and normal and asthmatic mice by flow cytometry. The regulatory effects of mouse CD9+ B cells on effector T cell death, cell cycle arrest, apoptosis, and mitochondrial depolarization were determined using yellow dye, propidium iodide, Annexin V, and JC-1 staining. MAPK phosphorylation was analyzed by western blotting. Patients with severe asthma and asthmatic mice both harbored less CD19+CD9+ B cells, although these cells displayed no defect in their capacity to induce T cell apoptosis. Molecular mechanisms of regulation of CD9+ B cells characterized in mouse showed that they induced effector T cell cycle arrest in sub G0/G1, leading to apoptosis in an IL-10-dependent manner. This process occurred through MAPK phosphorylation and activation of both the intrinsic and extrinsic pathways. This study characterizes the molecular mechanisms underlying the regulation of CD9+ B cells to induce effector T cell apoptosis in mice and humans via IL-10 secretion. Defects in CD9+ B cells in blood from patients with severe asthma reveal new insights into the lack of regulation of inflammation in these patients

Performance of a large scale prototype of the ATLAS accordion electromagnetic calorimeter

A 2 m long prototype of a lead-liquid argon electromagnetic calorimeter with accordion-shaped electrodes, conceived as a sector of the barrel calorimeter of the future ATLAS experiment at the LHC, has been tested with electron and pion beams in the energy range 10 to 287 GeV. A sampling term of 10%/root E(GeV) was obtained for electrons in the rapidity range 0 < eta < 1, while the constant term measured over an area of about 1 m(2) is 0.69%. With a cell size of 2.7 cm the position resolution is. about 4 mm/root E(GeV)

Performance of an endcap prototype of the ATLAS accordion electromagnetic calorimeter

The design and construction of a lead-liquid argon endcap calorimeter prototype using an accordion geometry and conceived as a sector of the inner wheel of the endcap calorimeter of the future ATLAS experiment at the LHC is described. The performance obtained using electron beam data is presented. The main results are an energy resolution with a sampling term below $11\%/\sqrt{E(\rm GeV)}$ and a small local constant term, a good linearity of the response with the incident energy and a global constant term of 0.8\% over an extended area in the rapidity range of $2.2 < \eta <2.9$. These properties make the design suitable for the ATLAS electromagnetic endcap calorimeter

Test beam results of a stereo preshower integrated in the liquid argon accordion calorimeter

This paper describes the construction of an integrated preshower within the RD3 liquid argon accordion calorimeter. It has a stereo view which enables the measurement of two transverse coordinates. The prototype was tested at CERN with electrons, photons and muons to validate its capability to work at LHC ( Energy resolution, impact point resolution, angular resolution, $\pi^o$/$\gamma$ rejection )