Anomalous diffusion of phospholipids and cholesterols in a lipid bilayer and its origins

Combining extensive molecular dynamics simulations of lipid bilayer systems of varying chemical composition with single-trajectory analyses we systematically elucidate the stochastic nature of the lipid motion. We observe subdiffusion over more than four orders of magnitude in time, clearly stretching into the sub-microsecond domain. The lipid motion delicately depends on the lipid chemistry, the lipid phase, and especially on the presence of cholesterol. We demonstrate that fractional Langevin equation motion universally describes the lipid motion in all phases including the gel phase, and in the presence of cholesterol. The results underline the relevance of anomalous diffusion in lipid bilayers and the strong effects of the membrane composition.Comment: 5 pages, 5 figures. Supplementary Material included in source files. Accepted to Phys Rev Let

Unexpected interfarm transmission dynamics during a highly pathogenic avian influenza epidemic

Next-generation sequencing technology is now being increasingly applied to study the within- and between-host population dynamics of viruses. However, information on avian influenza virus evolution and transmission during a naturally occurring epidemic is still limited. Here, we use deep-sequencing data obtained from clinical samples collected from five industrial holdings and a backyard farm infected during the 2013 highly pathogenic avian influenza (HPAI) H7N7 epidemic in Italy to unravel (i) the epidemic virus population diversity, (ii) the evolution of virus pathogenicity, and (iii) the pathways of viral transmission between different holdings and sheds. We show a high level of genetic diversity of the HPAI H7N7 viruses within a single farm as a consequence of separate bottlenecks and founder effects. In particular, we identified the cocirculation in the index case of two viral strains showing a different insertion at the hemagglutinin cleavage site, as well as nine nucleotide differences at the consensus level and 92 minority variants. To assess interfarm transmission, we combined epidemiological and genetic data and identified the index case as the major source of the virus, suggesting the spread of different viral haplotypes from the index farm to the other industrial holdings, probably at different time points. Our results revealed interfarm transmission dynamics that the epidemiological data alone could not unravel and demonstrated that delay in the disease detection and stamping out was the major cause of the emergence and the spread of the HPAI strain

Long-chain GM1 gangliosides alter transmembrane domain registration through interdigitation

Extracellular and cytosolic leaflets in cellular membranes are distinctly different in lipid composition, yet they contribute together to signaling across the membranes. Here we consider a mechanism based on long-chain gangliosides for coupling the extracellular and cytosolic membrane leaflets together. Based on atomistic molecular dynamics simulations, we find that long-chain GM1 in the extracellular leaflet exhibits a strong tendency to protrude into the opposing bilayer leaflet. This interdigitation modulates the order in the cytosolic monolayer and thereby strengthens the interaction and coupling across a membrane. Coarse-grained simulations probing longer time scales in large membrane systems indicate that GM1 in the extracellular leaflet modulates the phase behavior in the cytosolic monolayer. While short-chain GM1 maintains phase-symmetric bilayers with a strong membrane registration effect, the situation is altered with long-chain GM1. Here, the significant interdigitation induced by long-chain GM1 modulates the behavior in the cytosolic GM1-free leaflet, weakening and slowing down the membrane registration process. The observed physical interaction mechanism provides a possible means to mediate or foster transmembrane communication associated with signal transduction. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe

Los valles tectónicos recientes de Rubielos de la Cerida (Teruel)

[Resumen] La actividad tectónica cuaternaria y reciente ha dado lugar en este área a un conjunto de depresiones alargadas de orientación submeridiana, enmarcadas por fallas, que constituyen valles tectónicos[Abstract] Quaternary and recent tectonic activity led to a series of elongated depressions in the studied area of roughly N-S orientation, framed by faults, and developping as tectonic valleys

First report outside Eastern Europe of West Nile virus lineage 2 related to the Volgograd 2007 strain, northeastern Italy, 2014

open11noWest Nile virus (WNV) is a Flavivirus transmitted to vertebrate hosts by mosquitoes, maintained in nature through an enzootic bird-mosquito cycle. In Europe the virus became of major public health and veterinary concern in the 1990s. In Italy, WNV re-emerged in 2008, ten years after the previous outbreak and is currently endemic in many areas of the country. In particular, the northeastern part of Italy experience continuous viral circulation, with human outbreaks caused by different genovariants of WNV lineage 1, Western-European and Mediterranean subcluster, and WNV lineage 2, Hungarian clade. Alongside the WNV National Surveillance Program that has been in place since 2002, regional surveillance plans were implemented after 2008 targeting mosquitoes, animals and humans.openRavagnan, Silvia; Montarsi, Fabrizio; Cazzin, Stefania; Porcellato, Elena; Russo, Francesca; Palei, Manlio; Monne, Isabella; Savini, Giovanni; Marangon, Stefano; Barzon, Luisa; Capelli, GioiaRavagnan, Silvia; Montarsi, Fabrizio; Cazzin, Stefania; Porcellato, Elena; Russo, Francesca; Palei, Manlio; Monne, Isabella; Savini, Giovanni; Marangon, Stefano; Barzon, Luisa; Capelli, Gioi

A new monoclonal antibody detects downregulation of protein tyrosine phosphatase receptor type γ in chronic myeloid leukemia patients

Background: Protein tyrosine phosphatase receptor gamma (PTPRG) is a ubiquitously expressed member of the protein tyrosine phosphatase family known to act as a tumor suppressor gene in many different neoplasms with mechanisms of inactivation including mutations and methylation of CpG islands in the promoter region. Although a critical role in human hematopoiesis and an oncosuppressor role in chronic myeloid leukemia (CML) have been reported, only one polyclonal antibody (named chPTPRG) has been described as capable of recognizing the native antigen of this phosphatase by flow cytometry. Protein biomarkers of CML have not yet found applications in the clinic, and in this study, we have analyzed a group of newly diagnosed CML patients before and after treatment. The aim of this work was to characterize and exploit a newly developed murine monoclonal antibody specific for the PTPRG extracellular domain (named TPγ B9-2) to better define PTPRG protein downregulation in CML patients. Methods: TPγ B9-2 specifically recognizes PTPRG (both human and murine) by flow cytometry, western blotting, immunoprecipitation, and immunohistochemistry. Results: Co-localization experiments performed with both anti-PTPRG antibodies identified the presence of isoforms and confirmed protein downregulation at diagnosis in the Philadelphia-positive myeloid lineage (including CD34+/CD38bright/dim cells). After effective tyrosine kinase inhibitor (TKI) treatment, its expression recovered in tandem with the return of Philadelphia-negative hematopoiesis. Of note, PTPRG mRNA levels remain unchanged in tyrosine kinase inhibitors (TKI) non-responder patients, confirming that downregulation selectively occurs in primary CML cells. Conclusions: The availability of this unique antibody permits its evaluation for clinical application including the support for diagnosis and follow-up of these disorders. Evaluation of PTPRG as a potential therapeutic target is also facilitated by the availability of a specific reagent capable to specifically detect its target in various experimental conditions

Morfología de vertientes y neotectónica en el Macizo de Javalambre (provincia de Teruel)

[Resumen] El modelado actual de las vertientes del macizo de Javalambre es consecuencia de tres tipos principales de procesos que actúan a partir de su elevación a comienzos del Plioceno -superior: (a) la dinámica periglaciar, (b) una etapa de activida~ tect6nica ocurrida hacia el Pleistoceno medio-superior, y (c) deslizamientos gravitacionales, translacionales y rotacionales producidos a favor de un sustrato plástico en las áreas de mayor incisión de la red -fluvial.Abstract] The present slope form in Javalambre area results from three principal types of processes which are active after its elevation in the early Upper Pliocene: (a) periglacial dynamics, (b) a tectonic phase in Middle-Upper Pleistocene, and (c) gravitational, translational and rotational landslides generated over plastic rocks in zones with a intensive fluvial incisio

General morphology, classification and biology of Cerambycidae

Single chapter permitted OA by publisher.falseUS