Genes for blood pressure: an opportunity to understand hypertension

Hypertension (HTN) is quantitatively the major cardiovascular risk factor and responsible for ∼50% of cardiovascular morbidity and mortality. Blood pressure (BP) is also a classical complex genetic trait with heritability estimates of 30-50%. Although much is known about BP regulation, the intrinsic origin of essential HTN remains obscure although many environmental factors are known. Analyses of rare monogenic syndromes of HTN have focused attention on pathways that involve renal sodium handling, and steroid hormone metabolism including the mineralocorticoid receptor activity. The genetic basis of common essential HTN on the other hand is only just becoming accessible through high-throughput approaches. Unbiased genome-wide analyses of BP genomics have identified 43 genetic variants associated with systolic, diastolic BP, and HTN. It is highly likely based on current findings that there are hundreds of such loci with small effects on BP, opening a perspective on the genetic architecture of BP that was unknown before. It is our hope that the knowledge of these and further loci will lead to improved understanding of BP pathophysiology and to the identification of new targets for drug therap

Passive remote sensing of columnar water vapour content above land surfaces. Part I: Theoretical algorithm development - Part II: Comparison of OVID measurements with radiosonde and DIAL measurements

Various efforts are currently being made to develop remote sensing techniques for high accuracy determination of atmospheric columnar water vapour content above land surfaces. Most of those algorithms are based on radiative transfer calcu lations, however, which have to be verified by spectral airborne or satellite measurements. Initial verification of a new algorithm with the aid of airborne spectral data using the spectrometer OVID (Optical Visible and near Infrared Detector), an airborne water vapour DIAL (Differential Absorption Lidar), an airc;raft humicap sensor and radiosonde data is performed dUIing a flight experiment over Southern Germany. This water vapour algorithm is also dedicated to the MERIS (MEdium Resolution Imaging Spectrometer) in strument on board ESA's satellite ENVISAT which will be launched 1999. Spatial water vapour gradients of &120 = 0.1 g/cm2 over a distance of 100 km were resolved by applying the OVID measurements. The error estimation of the absolute value of the retrieved water vapour contents poses· some problems due to insufficient additional temporal and spatial radiosonde data. However, the principal feasibility has been prove

Model catalysts synthesized by the di-block copolymer inverse micelle method: insights on nanoparticle formation and network stability within the environmental TEM

MICROSCOPIE+MEME+FCA:EEH:LBU:TEPInternational audienceThe di-block copolymer inverse micelle method, where an amphiphilic di-block copolymer dissolved in toluene creates a system of inverse micelles, is a rather simple method to obtain well controlled supported metallic nanoparticles once the micelle core is charged with metallic salts. Supported metallic catalysts can be obtained in this way on both flat (model catalysts) and powder (realistic catalysts) supports [1]. Our main interest deals with applications of bimetallic catalyst systems that we investigate from extended catalytic surfaces [2] to realistic catalysts [3]; the idea being to isolate and understand the role of important physico-chemical parameters on the catalytic behaviour of these systems in the shape of model catalytic surfaces and try to extrapolate them to realistic catalysts. This is very important for the controlled design of catalysts with specific properties. In this way we can, not only spend less active material (often rare and expensive), but also avoid unnecessary poisoning while keeping high activity (stability) and finely tune the selectivity to avoid deleterious unwanted products; these are important points to be able to achieve environmentally friendly and sustainable catalytic processes. Self-organized nanoparticles on flat surfaces is an intermediate configuration between extended catalytic surfaces and realistic catalysts and a necessary step to better extrapolate results between model and realistic systems. We have thus extended the di-block copolymer method to the synthesis of bimetallic catalysts [4]. In our presentation we will deal with a PdAu system, obtained from a PS-b-P2VP copolymer micellar solution that we transfer by spin-coating to a surface of a SiNx eletron-transparent films on dedicated microchips than are heated in Wildfire sample holder (DENS Solutions) within an objective lens aberration-corrected environmental TEM (Titan ETEM G2 80-300 kV from ThermoFisher Scientific) so that we can study in situ the behaviour of such a system in variable temperature and gas pressure. We observed the formation of the individual particles from the seeds within the core of the micelles in the presence of oxygen in variable temperature; sintering of the seeds within the micelle cores starts at 350°C and is completed at 500°C, temperatures that correspond, respectively, to the onset of the copolymer decomposition and to its quasi-completed decomposition [5]. We also observed that the network of nanoparticles is stable under oxygen up to 900°C and that, above this temperature, the network is modified only by the decomposition of the nanoparticles (when we approach their melting point).The authors acknowledge the French Microscopy and Atom probe network (METSA) and the Consortium Lyon – St-Etienne de Microscopie (CLYM) for supporting this work.References:[1] B. Roldan Cuenya, Accounts of Chemical Research 46 (2013) 1682.[2] MC Saint-Lager et al., ACS Catalysis 9 (2019) 4448.[2] B. Pongthawornsakun et al., Applied Catalysis A: General 549 (2018) 1.[4] E. Ehret et al., Nanoscale 7 (2015) 13239.[5] T. Orhan Lekesiz et al., Journal of Analytical and Applied Pyrolysis 106 (2014) 81

Static and dynamic 3D culture of neural precursor cells on macroporous cryogel microcarriers

Neural precursor cells have been much studied to further our understanding of the far-reaching and controversial question of adult neurogenesis. Currently, differentiation of primary neural precursor cells from the mouse dentate gyrus via 2-dimentional in vitro culture yields low numbers of neurons, a major hindrance to the field of study. 3-dimentional “neurosphere” culture allows better 3D cell-cell contact, but control over cell differentiation is poor because nutrition and oxygen restrictions at the core of the sphere causes spontaneous differentiation, predominantly to glial cells, not neurons. Our group has developed macroporous scaffolds, which overcome the above-mentioned problems, allowing long-term culture of neural stem cells, which can be differentiated into a much higher yield of neurons. Herein we describe a method for culturing neural precursor cells on RGD peptide functionalized-heparin containing cryogel scaffolds, either in standard non-adherent well-plates (static culture) or in spinner flasks (dynamic culture). This method includes: • The synthesis and characterization of heparin based microcarriers. • A “static” 3D culture method for that does not require spinner flask equipment. • “Dynamic” culture in which cell loaded microcarriers are transferred to a spinner flask. © 2020 The Author

Development of Social Vocalizations in Mice

Adult mice are highly vocal animals, with both males and females vocalizing in same sex and cross sex social encounters. Mouse pups are also highly vocal, producing isolation vocalizations when they are cold or removed from the nest. This study examined patterns in the development of pup isolation vocalizations, and compared these to adult vocalizations. In three litters of CBA/CaJ mice, we recorded isolation vocalizations at ages postnatal day 5 (p5), p7, p9, p11, and p13. Adult vocalizations were obtained in a variety of social situations. Altogether, 28,384 discrete vocal signals were recorded using high-frequency-sensitive equipment and analyzed for syllable type, spectral and temporal features, and the temporal sequencing within bouts. We found that pups produced all but one of the 11 syllable types recorded from adults. The proportions of syllable types changed developmentally, but even the youngest pups produced complex syllables with frequency-time variations. When all syllable types were pooled together for analysis, changes in the peak frequency or the duration of syllables were small, although significant, from p5 through p13. However, individual syllable types showed different, large patterns of change over development, requiring analysis of each syllable type separately. Most adult syllables were substantially lower in frequency and shorter in duration. As pups aged, the complexity of vocal bouts increased, with a greater tendency to switch between syllable types. Vocal bouts from older animals, p13 and adult, had significantly more sequential structure than those from younger mice. Overall, these results demonstrate substantial changes in social vocalizations with age. Future studies are required to identify whether these changes result from developmental processes affecting the vocal tract or control of vocalization, or from vocal learning. To provide a tool for further research, we developed a MATLAB program that generates bouts of vocalizations that correspond to mice of different ages

Mixing of mineral dust with urban pollution aerosol over Dakar (Senegal): Impact on dust physico-chemical and radiative properties.

In the framework of the Saharan Mineral Dust Experiment (SAMUM) in 2008, the mixing of the urban pollution plume of Dakar (Senegal) with mineral dust was studied in detail using the German research aircraft Falcon which was equipped with a nadir-looking high spectral resolution lidar (HSRL) and extensive aerosol in situ instrumentation. The mineral dust layer as well as the urban pollution plume were probed remotely by the HSRL and in situ. Back trajectory analyses were used to attribute aerosol samples to source regions.We found that the emission from the region of Dakar increased the aerosol optical depth (532 nm) from approximately 0.30 over sea and over land east of Dakar to 0.35 in the city outflow. In the urban area, local black carbon (BC) emissions, or soot respectively, contributed more than 75% to aerosol absorption at 530 nm. In the dust layer, the single-scattering albedo at 530 nm was 0.96 â�� 0.99, whereas we found a value of 0.908 �± 0.018 for the aerosol dominated by urban pollution. After 6h of transport over the North Atlantic, the externally mixed mode of secondary aerosol particles had almost completely vanished, whereas the BC agglomerates (soot) were still externally mixed with mineral dust particles