82 research outputs found
A transcribed enhancer dictates mesendoderm specification in pluripotency.
Enhancers and long noncoding RNAs (lncRNAs) are key determinants of lineage specification during development. Here, we evaluate remodeling of the enhancer landscape and modulation of the lncRNA transcriptome during mesendoderm specification. We sort mesendodermal progenitors from differentiating embryonic stem cells (ESCs) according to Eomes expression, and find that enhancer usage is coordinated with mesendoderm-specific expression of key lineage-determining transcription factors. Many of these enhancers are associated with the expression of lncRNAs. Examination of ESC-specific enhancers interacting in three-dimensional space with mesendoderm-specifying transcription factor loci identifies MesEndoderm Transcriptional Enhancer Organizing Region (Meteor). Genetic and epigenetic manipulation of the Meteor enhancer reveal its indispensable role during mesendoderm specification and subsequent cardiogenic differentiation via transcription-independent and -dependent mechanisms. Interestingly, Meteor-deleted ESCs are epigenetically redirected towards neuroectodermal lineages. Loci, topologically associating a transcribed enhancer and its cognate protein coding gene, appear to represent therefore a class of genomic elements controlling developmental competence in pluripotency
Long-term biochemical results after high-dose-rate intensity modulated brachytherapy with external beam radiotherapy for high risk prostate cancer
Abstract Background Biochemical control from series in which radical prostatectomy is performed for patients with unfavorable prostate cancer and/or low dose external beam radiation therapy are given remains suboptimal. The treatment regimen of HDR brachytherapy and external beam radiotherapy is a safe and very effective treatment for patients with high risk localized prostate cancer with excellent biochemical control and low toxicity.</p
A Tabletop X-Ray Tomography Instrument for Nanometer-Scale Imaging: Integration of a Scanning Electron Microscope with a Transition-Edge Sensor Spectrometer
X-ray nanotomography is a powerful tool for the characterization of nanoscale
materials and structures, but is difficult to implement due to competing
requirements on X-ray flux and spot size. Due to this constraint,
state-of-the-art nanotomography is predominantly performed at large synchrotron
facilities. Compact X-ray nanotomography tools operated in standard analysis
laboratories exist, but are limited by X-ray optics and destructive sample
preparation techniques. We present a laboratory-scale nanotomography instrument
that achieves nanoscale spatial resolution while changing the limitations of
conventional tomography tools. The instrument combines the electron beam of a
scanning electron microscope (SEM) with the precise, broadband X-ray detection
of a superconducting transition-edge sensor (TES) microcalorimeter. The
electron beam generates a highly focused X-ray spot in a metal target, while
the TES spectrometer isolates target photons with high signal-to-noise. This
combination of a focused X-ray spot, energy-resolved X-ray detection, and
unique system geometry enable nanoscale, element-specific X-ray imaging in a
compact footprint. The proof-of-concept for this approach to X-ray
nanotomography is demonstrated by imaging 160 nm features in three dimensions
in a Cu-SiO2 integrated circuit, and a path towards finer resolution and
enhanced imaging capabilities is discussed.Comment: The following article has been submitted to Physical Review Applie
Harmful Elements in Estuarine and Coastal Systems
Estuaries and coastal zones are dynamic transitional systems which provide many economic and ecological benefits to humans, but also are an ideal habitat for other organisms as well. These areas are becoming contaminated by various anthropogenic activities due to a quick economic growth and urbanization. This chapter explores the sources, chemical speciation, sediment accumulation and removal mechanisms of the harmful elements in estuarine and coastal seawaters. It also describes the effects of toxic elements on aquatic flora and fauna. Finally, the toxic element pollution of the Venice Lagoon, a transitional water body located in the northeastern part of Italy, is discussed as a case study, by presenting the procedures adopted to measure the extent of the pollution, the impacts on organisms and the restoration activities
Vie quotidienne et pouvoir dans trois quartiers de Pékin : une microsociologie politique comparée des modes de gouvernement urbain au début du 21 e siècle
Cette thèse propose une réflexion sur l'exercice du pouvoir à partir d'enquêtes effectuées dans trois quartiers contrastés de Pékin (2007-2009). Cette approche « par le bas » s'intéresse à la vie quotidienne en croisant microsociologie urbaine et politique comparée. Le quartier, site de pouvoir, est traversé par différentes formes d'hétéro-contrôle (politiques publiques), de contrôle social (normes) et d'autocontrôle. L'espace d'un quartier se construit sur la base d'interactions et de mises en scène des habitants, producteurs d'arts de faire et de conventions, mais aussi des travailleurs, notamment les agents du comité de résidents. Cette instance, qui ne relève pas officiellement de l'administration, est au cœur de la réforme de l'action publique de construction des communautés de quartier (shequ). Maillon essentiel du contact entre les habitants et la chaîne de l'administration, elle constitue un type particulier de street-level bureaucracy. La domination s'établit à un double niveau, à partir des ambitions étatiques de construction d'une métropole internationale abritant des citadins « modernes et civilisés », mais aussi à partir des désirs de la population (confort, ordre, stabilité). Cet agencement d'intérêts différents a convergé vers le nouveau modèle de résidence (xiaoqu), qui génère une matrice d'assujettissement (logique de marché), mais aussi de subjectivation, les pratiques des individus (routines et contestation) étant productrices de nouveaux cadres. Le quartier devient alors le lieu où les individus construisent leur propre domination, un lieu où s'observe la formation locale de l'État, un lieu de plus en plus connecté à l'image sociale de la « vie bonne ».This thesis offers a study of power exercise in three different types of neighbourhoods in Beijing, China, where the author carried out fieldwork from 2007 until 2009. This approach « from below » aims at understanding daily life by crisscrossing urban microsociology and comparative politics. The urban neighbourhood, as a site of power, undergoes different forms of hetero-control, social control and self-control. The neighourhood space is produced by the interactions and theatrical dispositions of the inhabitants, but also by the local workers, among whom the people who work in residents' committees. This organization located at the root-level, though not officially part of the urban administration, is involved in the reform of local public action known as « neighbourhood communities » building (shequ jianshe). An essential link between the inhabitants and the upper-level administration, the committee can be seen as a new generation of street-level bureaucracy. The process of domination is initiated both by the state's strategies aiming at shaping modern civilized citizens living in an international metropolis, and by the inhabitants' yearning for comfort, order, stability. The converging of these different interests leads to the new residential model (xiaoqu), which creates mechanisms of submission (to the logic of the market) as well as subjection (the individuals being able to invent new frames with their daily practices). The eneighbourhood has thus become the core of the state's local formation, a place where each individual is more and more responsible of his own domination, a place more and more conform to the social image of the « good life »
Place des apports oraux en acides gras oméga-3 dans la mucoviscidose [Relevance of omega-3 fatty acid oral supplementation in cystic fibrosis]
Chronic inflammation and fatty acid deficiency, in particular in docosahexaenoic acid (DHA, C22:6-n3), occurring in cystic fibrosis patients, are two convincing arguments urging the use of polyunsaturated fatty acids (PUFA) omega-3 in this population. PUFA omega-3 oral dietary intake position in the cystic fibrosis treatment is however not clear despite many years of clinical research. This review article sets out the reasons that conduct nutritionists to try this approach and reviews the results published until nowadays
Detection et prise en charge precoce de la primo-infection a Pseudomonas aeruginosa chez les patients avec mucoviscidose. [Detection and management of early Pseudomonas aeruginosa infection in patients with cystic fibrosis]
Initial Pseudomonas aeruginosa infection in patients with cystic fibrosis is a key step in pulmonary evolution of the disease. This first infection is most of the time early in life and gives some practical problems to the clinicians. It is important to look for colonisation with Pseudomonas aeruginosa as often as possible, at least every 3 month, by sputum culture when the child is able to or with induced sputum by hypertonic saline nebulisation. Treatment with inhalation of an antibiotic, preferably tobramycin for a 28 days course. Efficacy of the treatment as to be assessed by new culture
"Naked Sugars of the Second Generation" : Asymmetric Synthesis of Long-Chain Polypropionates and Analogues Starting with Acetone.
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