University of Paris

About: University of Paris is a education organization based out in Paris, France. It is known for research contribution in the topics: Population & Transplantation. The organization has 102426 authors who have published 174180 publications receiving 5041753 citations. The organization is also known as: Sorbonne.

The vascular smooth muscle cell in arterial pathology: a cell that can take on multiple roles.

Abstract: Vascular smooth muscle cells (VSMCs) are the stromal cells of the vascular wall, continually exposed to mechanical signals and biochemical components generated in the blood compartment. They are involved in all the physiological functions and the pathological changes taking place in the vascular wall. Owing to their contractile tonus, VSMCs of resistance vessels participate in the regulation of blood pressure and also in hypertension. VSMCs of conduit arteries respond to hypertension-induced increases in wall stress by an increase in cell protein synthesis (hypertrophy) and extracellular matrix secretion. These responses are mediated by complex signalling pathways, mainly involving RhoA and extracellular signal-regulated kinase1/2. Serum response factor and miRNA expression represent main mechanisms controlling the pattern of gene expression. Ageing also induces VSMC phenotypic modulation that could have influence on cell senescence and loss of plasticity and reprogramming. In the early stages of human atheroma, VSMCs support the lipid overload. Endocytosis/phagocytosis of modified low-density lipoproteins, free cholesterol, microvesicles, and apoptotic cells by VSMCs plays a major role in the progression of atheroma. Migration and proliferation of VSMCs in the intima also participate in plaque progression. The medial VSMC is the organizer of the inwardly directed angiogenic response arising from the adventitia by overexpressing vascular endothelial growth factor in response to lipid-stimulated peroxisome proliferator-activated receptor-γ, and probably also the organizer of the adventitial immune response by secreting chemokines. VSMCs are also involved in the response to proteolytic injury via their ability to activate blood-borne proteases, to secrete antiproteases, and to clear protease/antiprotease complexes.

El Niño–Southern Oscillation complexity

Abstract: El Nino events are characterized by surface warming of the tropical Pacific Ocean and weakening of equatorial trade winds that occur every few years Such conditions are accompanied by changes in atmospheric and oceanic circulation, affecting global climate, marine and terrestrial ecosystems, fisheries and human activities The alternation of warm El Nino and cold La Nina conditions, referred to as the El Nino–Southern Oscillation (ENSO), represents the strongest year-to-year fluctuation of the global climate system Here we provide a synopsis of our current understanding of the spatio-temporal complexity of this important climate mode and its influence on the Earth system

Revised Stellar Properties of Kepler Targets for the Quarter 1-16 Transit Detection Run

Abstract: We present revised properties for 196,468 stars observed by the NASA Kepler mission and used in the analysis of Quarter 1-16 (Q1-Q16) data to detect and characterize transiting planets. The catalog is based on a compilation of literature values for atmospheric properties (temperature, surface gravity, and metallicity) derived from different observational techniques (photometry, spectroscopy, asteroseismology, and exoplanet transits), which were then homogeneously fitted to a grid of Dartmouth stellar isochrones. We use broadband photometry and asteroseismology to characterize 11,532 Kepler targets which were previously unclassified in the Kepler Input Catalog (KIC). We report the detection of oscillations in 2762 of these targets, classifying them as giant stars and increasing the number of known oscillating giant stars observed by Kepler by ~20% to a total of ~15,500 stars. Typical uncertainties in derived radii and masses are ~40% and ~20%, respectively, for stars with photometric constraints only, and 5%-15% and ~10% for stars based on spectroscopy and/or asteroseismology, although these uncertainties vary strongly with spectral type and luminosity class. A comparison with the Q1-Q12 catalog shows a systematic decrease in radii of M dwarfs, while radii for K dwarfs decrease or increase depending on the Q1-Q12 provenance (KIC or Yonsei-Yale isochrones). Radii of F-G dwarfs are on average unchanged, with the exception of newly identified giants. The Q1-Q16 star properties catalog is a first step toward an improved characterization of all Kepler targets to support planet-occurrence studies.

EPISEPSIS: a reappraisal of the epidemiology and outcome of severe sepsis in French intensive care units.

Abstract: Objective Ten years ago 8.4% of patients in French intensive care units (ICUs) were found to have severe sepsis or shock and 56% died in the hospital. As novel therapies for severe sepsis are emerging, updated epidemiological information is required. Design and setting An inception cohort study conducted in 206 ICUs of randomly selected hospitals over a 2-week period in 2001, including all patients meeting criteria for clinically or microbiologically documented severe sepsis (with > or =1 organ dysfunction). Measurements and results Among 3738 admissions, 546 (14.6%) patients experienced severe sepsis or shock, of which 30% were ICU-acquired. The median age of patients was 65 years, and 54.1% had at least one chronic organ system dysfunction. The median (range) Simplified Acute Physiology Score (SAPS II) and Sequential Organ Failure Assessment (SOFA) at onset of severe sepsis were 48 (2-129) and 9 (1-24), respectively. Mortality was 35% at 30 days; at 2 months the mortality rate was 41.9%, and 11.4% of patients remained hospitalized. The median (range) hospital stay was 25 (0-112) days in survivors and 7 (0-90) days in non-survivors. Chronic liver and heart failure, acute renal failure and shock, SAPS II at onset of severe sepsis and 24-h total SOFA scores were the independent risk factors most strongly associated with death. Conclusions Although the attack rate of severe sepsis in French ICUs appears to have increased over the past decade, its associated mortality has decreased, suggesting improved management of patients. Severe sepsis incurs considerable resources use, and implementation of effective management strategies and continued research efforts are needed.