Anoctamin 6 is localized in the primary cilium of renal tubular cells and is involved in apoptosis-dependent cyst lumen formation

International audiencePrimary cilia are antenna-like structures projected from the apical surface of various mammalian cells including renal tubular cells. Functional or structural defects of the cilium lead to systemic disorders comprising polycystic kidneys as a key feature. Here we show that anoctamin 6 (ANO6), a member of the anoctamin chloride channel family, is localized in the primary cilium of renal epithelial cells in vitro and in vivo. ANO6 was not essential for cilia formation and had no effect on in vitro cyst expansion. However, knockdown of ANO6 impaired cyst lumen formation of MDCK cells in three-dimensional culture. In the absence of ANO6, apoptosis was reduced and epithelial cells were incompletely removed from the center of cell aggregates, which form in the early phase of cystogenesis. In line with these data, we show that ANO6 is highly expressed in apoptotic cyst epithelial cells of human polycystic kidneys. These data identify ANO6 as a cilium-associated protein and suggest its functional relevance in cyst formation

Seismic behavior of composite concrete floor without earthquake design provisions Part 1 : experimental program

International audienceIn some existing nuclear facilities in France, composite concrete floors were designed to support only gravity loads. Therefore those slabs were constructed without earthquake design provisions. In order to assess the structural dynamic behaviour and seismic margins of such slabs with regards to the resistance calculated with construction codes used in France for existing buildings, CEA and IRSN launched in 2008 a research program which is divided in two parts (1) an experimental program performed on two full scale identical models one subjected to a mono-axial in-plane static cyclic loading up to failure tested at GINGER CEBTP and one subjected to a series of bi-axial horizontal seismic excitation at CEA/Saclay on AZALEE shaking table, (2) a numerical analysis program of the tests results using the finite element code CAST3M developed at CEA/Saclay.This paper is dedicated to the presentation of the two experimental campaignsPresentation of the models (geometry, reinforcement detailing, construction, material properties),Instrumentation of the two models, Experimental campaign protocol,Main tests results. Numerical analyses performed after the experimental campaigns are presented in a second paper in this conference

Acute renal failure with lambda light chain-derived crystals in a patient with IgD myeloma

International audienceKidney involvement with immunoglobulin crystals usually relates to a light chain of the kappa type, in MGUS or smoldering myeloma, frequently causing Fanconi's syndrome with progressive renal insufficiency. We report on a case with severe myeloma featuring lambda light chain-derived crystals and acute kidney injury. Histology showed acute tubular necrosis and tubule obstruction with crystals, which were also abundant inside tubule epithelial cells, macrophages and bone marrow plasma cells. The light chain variable domain had a normal overall primary structure but included 11 somatic mutations, 3 of which likely increased the surface hydrophobicity, as observed in previously reported kappa-type crystals

Southern ocean carbon and heat impact on climate

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea–ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate. This article is part of a discussion meeting issue ‘Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities’

Southern Ocean carbon and heat impact on climate

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal time scales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate (SO-CHIC) programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean, and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation, and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate