Expresión de ICAM-1 en el Endotelio de Arterias Humanas Mediante Inmunohistoquímica

Moore-Carrasco, R (reprint author), Univ Talca, Fac Ciencias Salud, Dept Bioquim Clin & Inmunohematol, Programa Invest Factores Riesgo Enfermedades Card, POB 747, Talca, Chile.Cardiovascular diseases (CVD) are the leading cause of death in the world. Among them the ischemic type are of great importance. where the development of atherosclerotic plaques is the central pathophysiological process. The study of atherosclerosis is critical to understand how this disease process begins and factors influencing its development. Various laboratory methods, including immunohistochemistry, allow the recognition of cells and molecules involved in the atheromatous process that are interacting according to the progression of the lesion. A marker of endothelial dysfunction is the increased expression of intercellular adhesion molecule ICAM-1. In this paper, an immunohistochemistry method was standardized for the adhesion molecule ICAM-1, and its expression was studied in healthy human arteries with atheromatous plaque. In samples of human arteries with atherosclerotic disease, the expression of ICAM-1 was observed lobe increased, but was hardly recognizable. This mainly because the tissue used as a control for standardization was a tonsil with an inflammatory process and hyperplasia, which significantly increases the expression of ICAM-1. The implementation of the immunohistochemistry method for ICAM-1 in human arteries will reveal endothelial dysfunction states that will enable a future design and implementation of methods of diagnosis in atherosclerotic processes in the early stages

Appointing Women to Boards: Is There a Cultural Bias?

Companies that are serious about corporate governance and business ethics are turning their attention to gender diversity at the most senior levels of business (Institute of Business Ethics, Business Ethics Briefing 21:1, 2011). Board gender diversity has been the subject of several studies carried out by international organizations such as Catalyst (Increasing gender diversity on boards: Current index of formal approaches, 2012), the World Economic Forum (Hausmann et al., The global gender gap report, 2010), and the European Board Diversity Analysis (Is it getting easier to find women on European boards? 2010). They all lead to reports confirming the overall relatively low proportion of women on boards and the slow pace at which more women are being appointed. Furthermore, the proportion of women on corporate boards varies much across countries. Based on institutional theory, this study hypothesizes and tests whether this variation can be attributed to differences in cultural settings across countries. Our analysis of the representation of women on boards for 32 countries during 2010 reveals that two cultural characteristics are indeed associated with the observed differences. We use the cultural dimensions proposed by Hofstede (Culture’s consequences: International differences in work-related values, 1980) to measure this construct. Results show that countries which have the greatest tolerance for inequalities in the distribution of power and those that tend to value the role of men generally exhibit lower representations of women on boards

Building galaxies by accretion and in-situ star formation

We examine galaxy formation in a cosmological AMR simulation, which includes two high resolution boxes, one centered on a 3 \times 10^14 M\odot cluster, and one centered on a void. We examine the evolution of 611 massive (M\ast > 10^10M\odot) galaxies. We find that the fraction of the final stellar mass which is accreted from other galaxies is between 15 and 40% and increases with stellar mass. The accreted fraction does not depend strongly on environment at a given stellar mass, but the galaxies in groups and cluster environments are older and underwent mergers earlier than galaxies in lower density environments. On average, the accreted stars are ~2.5 Gyrs older, and ~0.15 dex more metal poor than the stars formed in-situ. Accreted stellar material typically lies on the outskirts of galaxies; the average half-light radius of the accreted stars is 2.6 times larger than that of the in-situ stars. This leads to radial gradients in age and metallicity for massive galaxies, in qualitative agreement with observations. Massive galaxies grow by mergers at a rate of approximately 2.6% per Gyr. These mergers have a median (mass-weighted) mass ratio less than 0.26 \pm 0.21, with an absolute lower limit of 0.20, for galaxies with M\ast ~ 10^12 M\odot. This suggests that major mergers do not dominate in the accretion history of massive galaxies. All of these results agree qualitatively with results from SPH simulations by Oser et al. (2010, 2012).Comment: 18 pages, 12 figures, submitted to MNRA

Measurement of the W boson mass

We present a measurement of the W boson mass in W -> ev decays using 1 fb^-1 of data collected with the D0 detector during Run II of the Fermilab Tevatron collider. With a sample of 499830 W -> ev candidate events, we measure M_W = 80.401 +- 0.043 GeV. This is the most precise measurement from a single experiment.Comment: As published in PR

Measurement of the t-channel single top quark production cross section

The D0 collaboration reports direct evidence for electroweak production of single top quarks through the t-channel exchange of a virtual W boson. This is the first analysis to isolate an individual single top quark production channel. We select events containing an isolated electron or muon, missing transverse energy, and two, three or four jets from 2.3 fb^-1 of ppbar collisions at the Fermilab Tevatron Collider. One or two of the jets are identified as containing a b hadron. We combine three multivariate techniques optimized for the t-channel process to measure the t- and s-channel cross sections simultaneously. We measure cross sections of 3.14 +0.94 -0.80 pb for the t-channel and 1.05 +-0.81 pb for the s-channel. The measured t-channel result is found to have a significance of 4.8 standard deviations and is consistent with the standard model prediction.Comment: 7 pages, 6 figure

Search for the standard model Higgs boson in tau final states

We present a search for the standard model Higgs boson using hadronically decaying tau leptons, in 1 inverse femtobarn of data collected with the D0 detector at the Fermilab Tevatron ppbar collider. We select two final states: tau plus missing transverse energy and b jets, and tau+ tau- plus jets. These final states are sensitive to a combination of associated W/Z boson plus Higgs boson, vector boson fusion and gluon-gluon fusion production processes. The observed ratio of the combined limit on the Higgs production cross section at the 95% C.L. to the standard model expectation is 29 for a Higgs boson mass of 115 GeV.Comment: publication versio

Search for resonant diphoton production with the D0 detector

We present a search for a narrow resonance in the inclusive diphoton final state using 2.7 fb-1 of data collected with the D0 detector at the Fermilab Tevatron ppbar Collider. We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.Comment: 7 pages, 3 figures

Search for charged massive long-lived particles with the D0 detector

We search for charged massive long-lived particles using 1.1 fb$^{-1}$ of data collected by the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider. Time-of-flight information is used to search for pair produced long-lived tau sleptons, gaugino-like charginos, and higgsino-like charginos. We find no evidence of a signal and set 95% C.L. cross section upper limits for staus, which vary from 0.31pb to 0.04pb for stau masses between 60 GeV and 300 GeV. We also set lower mass limits of 206 GeV (171 GeV) for pair produced charged gauginos (higgsinos).Comment: To be submitted to Phys. Rev. Letters, V2: updated the figures and references, V3: final version submitted to PRL and changes in title and abstracts from "stable" to "long-lived

Exogenous spatial precuing reliably modulates object processing but not object substitution masking

Object substitution masking (OSM) is used in behavioral and imaging studies to investigate processes associated with the formation of a conscious percept. Reportedly, OSM occurs only when visual attention is diffusely spread over a search display or focused away from the target location. Indeed, the presumed role of spatial attention is central to theoretical accounts of OSM and of visual processing more generally (Di Lollo, Enns, & Rensink, Journal of Experimental Psychology: General 129:481–507, 2000). We report a series of five experiments in which valid spatial precuing is shown to enhance the ability of participants to accurately report a target but, in most cases, without affecting OSM. In only one experiment (Experiment 5) was a significant effect of precuing observed on masking. This is in contrast to the reliable effect shown across all five experiments in which precuing improved overall performance. The results are convergent with recent findings from Argyropoulos, Gellatly, and Pilling (Journal of Experimental Psychology: Human Perception and Performance 39:646–661, 2013), which show that OSM is independent of the number of distractor items in a display. Our results demonstrate that OSM can operate independently of focal attention. Previous claims of the strong interrelationship between OSM and spatial attention are likely to have arisen from ceiling or floor artifacts that restricted measurable performance

Estandarización de un modelo de trombosis arterial en ratas inducida por cloruro férrico

79 p.Las enfermedades cardiovasculares (ECV) son la primera causa de morbilidad y mortalidad tanto en países industrializados, como en vías de desarrollo. Estas enfermedades tienen como etiología principal, la trombosis producida sobre la configuración preexistente de una placa ateromatosa, todo este proceso además potenciado por la presencia de factores de riesgo. Junto con promover la disminución de factores de riesgo cardiovascular (FRCV), es necesario avanzar en el conocimiento de la fisiopatología de la aterotrombosis, en búsqueda de nuevas estrategias de tratamiento. Actualmente son ampliamente utilizados los fármacos antitrombóticos en la práctica clínica, especialmente los antiagregantes plaquetarios. Sin embargo, se ha visto que éstos no erradican los eventos trombóticos, lo que ha promovido el desarrollo y evaluación de nuevas estrategias antitrombóticas, tanto farmacológicas como naturales. En este contexto es muy importante contar con un modelo animal de trombosis arterial, que nos permita estudiar la fisiopatología de la trombosis arterial y evaluar “in vivo” la efectividad de las nuevas terapias antitrombóticas y las estrategias de prevención como el ejercicio y/o dieta saludable. Esta memoria tuvo como objetivo estandarizar un modelo de trombosis arterial “in vivo” inducida por cloruro férrico (FeCl3). Para lo cuál se les disecó la arteria carótida común a un grupo de ratas Wistar y se les aplicó FeCl3 en la superficie adventicia de la arteria mediante un papel filtro impregnado en una solución al 25% de FeCl3 por 3 minutos. Luego de los cuales se procedió a tomar el tiempo de oclusión trombótica del flujo sanguíneo arterial. Se estandarizó que para un grupo de ratas Wistar sometidas a las mismas condiciones, una concentración de 25% de FeCl3, el mismo tamaño de papel filtro, los tiempos de oclusión trombótica tuvieron una baja dispersión, con tiempos de oclusión trombótica similares, con una media de 9 minutos con 39 segundos y una desviación estándar de alrededor de 57 seg. A partir de éstos resultados, es posible concluir que éste es un método totalmente reproducible y es la base para futuras investigaciones en las cuales se puedan investigar la implicancia sobre los tiempos de oclusión trombótica de diversos tratamientos ya sea farmacológicos o naturales y diferentes estrategias de prevención de eventos trombóticos. Palabras claves: Trombosis arterial, Enfermedades cardiovasculares, Modelo de trombosis, Experimentación animal./ ABSTRACT: Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality in both industrialized and in developing countries. These diseases have as their primary etiology, thrombosis produced on the existing configuration of an atheromatous plaque, this process also enhanced by the presence of risk factors. Along with promoting the reduction of cardiovascular risk factors (CVRF), it is necessary to advance the understanding of the pathophysiology of atherothrombosis, in search of new treatment strategies. Currently there are antithrombotic drugs widely used in clinical practice, especially antiplatelets. However, we have seen that they do not eradicate thrombotic events, which has promoted the development and evaluation of new antithrombotic strategies, both pharmacological and natural. In this context it is very important to have an animal model of arterial thrombosis, which allows us to study the pathophysiology of arterial thrombosis and evaluate "in vivo" the effectiveness of new antithrombotic therapies and prevention strategies such as exercise and diet healthy. This report aimed to standardize an arterial thrombosis model "in vivo" induced by ferric chloride (FeCl3). For which are common carotid artery dissected a group of Wistar rats and FeCl3 was applied to the adventitial surface of the artery with a filter paper soaked in a 25% solution of FeCl3 for 3 minutes. After which we proceeded to take the time to thrombotic occlusion of arterial blood flow. Which was standardized for a group of Wistar rats subjected to the same conditions, a concentration of 25% FeCl3, the same filter paper size, thrombotic occlusion times were low dispersion, with thrombotic occlusion times similar, with half of 9 minutes and 39 seconds with a standard deviation of about 57 sec. From these results, we can conclude that this is a completely reproducible method and is the basis for future research in which they can investigate the implications for thrombotic occlusion times of various pharmacological treatments either natural or different prevention strategies thrombotic events. Keywords: Arterial thrombosis, ca