Filtration and deliquoring of actinides oxalates : modelling and optimization

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Filtration et drainage d'oxalates d'actinides : modélisation et optimisation

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Influence of particle properties and working pressures on cake dewatering

International audienc

New filterability and compressibility test cell design for nuclear product

International audienc

Influence of particle properties on cake resistance and compressibility : a modelling study

International audienc

Cryo-EM study of an archaeal 30S initiation complex gives insights into evolution of translation initiation

International audienceArchaeal translation initiation occurs within a macromolecular complex containing the small ribosomal subunit (30S) bound to mRNA, initiation factors aIF1, aIF1A and the ternary complex aIF2:GDPNP:Met-tRNAiMet. Here, we determine the cryo-EM structure of a 30S:mRNA:aIF1A:aIF2:GTP:Met-tRNAiMet complex from Pyrococcus abyssi at 3.2 Å resolution. It highlights archaeal features in ribosomal proteins and rRNA modifications. We find an aS21 protein, at the location of eS21 in eukaryotic ribosomes. Moreover, we identify an N-terminal extension of archaeal eL41 contacting the P site. We characterize 34 N4-acetylcytidines distributed throughout 16S rRNA, likely contributing to hyperthermostability. Without aIF1, the 30S head is stabilized and initiator tRNA is tightly bound to the P site. A network of interactions involving tRNA, mRNA, rRNA modified nucleotides and C-terminal tails of uS9, uS13 and uS19 is observed. Universal features and domain-specific idiosyncrasies of translation initiation are discussed in light of ribosomal structures from representatives of each domain of life

Filtration Process Optimization: Rheological Behavior of a Filter Cake at Different Moisture Contents

International audienceTransferring a wet cake from a filter to a dryer or furnace could severely lower the productivity of a whole process when the wet cake exhibits high viscosity and a sticky paste behavior. Depending on their moisture content, three distinct regions of rheological behavior were identified. Among them, only the granular solid type had sufficient flowability during the transfer operation. It was possible to discriminate the flow behavior more quantitatively by determining two transition values of moisture content. Rheological measurements were carried out at a constant shear rate representative of that encountered in the mechanical transfer system used at plant scale. The use of vane geometry for the rheometer was necessary to ensure an accurate repeatability of the viscosity measurements

Bevacizumab/docetaxel association is more efficient than docetaxel alone in reducing breast and prostate cancer cell growth: a new paradigm for understanding the therapeutic effect of combined treatment.

Bevacizumab (Bvz), a Vascular Endothelial Growth Factor (VEGF)-targeted humanised monoclonal antibody, provides clinical benefit in combination with docetaxel (DXL), a microtubule-stabilising agent, in the treatment of metastatic breast and prostate cancers. Since VEGF and their receptors are expressed by tumour cells, we hypothesised that Bvz, in addition to its impact on neo-vascularisation, could have an impact on tumour cells and enhance the DXL activity. Hence, we studied the effect of DXL and Bvz on metastatic breast (MDA MB-231) and prostate (PC3) cancer cells lines. Bvz alone did not decrease cell proliferation but in combination with DXL, Bvz enhanced the anti-proliferative activity of DXL. Other anti-angiogenic factors Sunitinib, Sorafenib and Gefitinib enhanced the anti-proliferative effect of DXL. qPCR experiments showed that DXL significantly increased the VEGF and VEGF receptor 2 (VEGF-R2) mRNA levels. Activation of VEGF and VEGF-R2 promoters demonstrated that enhanced mRNA levels are partly due to transcriptional activation. ELISA assays showed that DXL induced accumulation of cytoplasmic VEGF but decreased extracellular levels by 39% (MDA) and 48% (PC3). Cell surface localisation of VEGF-R2 was increased by DXL alone, but decreased after combined treatment of DXL plus Bvz. Abnormal expression of VEGF-R2 was also shown on breast and prostate tumour samples reinforcing the results obtained on cellular models. In conclusion, DXL and Bvz in combination decreased extracellular VEGF and VEGF-R2 levels at the plasma membrane thereby blocking an important growth/survival loop. Thus, the combined therapeutic impact of Bvz and DXL observed in clinical trials is associated with enhanced anti-proliferative activity and inhibition of the vascular network