Universidad del Desarrollo

About: Universidad del Desarrollo is a education organization based out in Santiago, Chile. It is known for research contribution in the topics: Population & Entrepreneurship. The organization has 2695 authors who have published 3578 publications receiving 52302 citations.

Can chest high-resolution computed tomography findings diagnose pulmonary alveolar microlithiasis?

Abstract: Objetivo:Analisar, retrospectivamente, as tomografias computadorizadas de alta resolucao (TCAR) de pacientes com microlitiase alveolar pulmonar, a fim de avaliar a frequencia dos padroes tomograficos e sua distribuicao no parenquima pulmonar.Materiais e Metodos:O estudo incluiu 13 pacientes (9 femininos e 4 masculinos) com idades variando de 9 a 59 anos (media de 34,5 anos). Os exames foram avaliados por dois observadores, de modo independente, e os casos discordantes, resolvidos por consenso. O criterio de inclusao foi a presenca de anormalidades na TCAR tipicas de microlitiase alveolar pulmonar, o que prescinde a necessidade de exame histopatologico. Entretanto, em 6 casos foram realizadas biopsias pulmonares.Resultados:Os achados tomograficos predominantes foram opacidades em vidro fosco e pequenos nodulos parenquimatosos, presentes em 100% dos casos, seguidos de pequenos nodulos subpleurais (92,3%), cistos subpleurais (84,6%), calcificacoes lineares subpleurais (69,2%), padrao de pavimentacao em mosaico (69,2%), fissura nodular (53,8%), calcificacao ao longo dos septos interlobulares (46,2%) e consolidacoes densas (46,2%).Conclusao:Quanto a distribuicao dos achados, houve acometimento preferencial dos tercos inferiores. Nao foi observado predominio de distribuicao dos sentidos axial e anteroposterior

A New State‐of‐the‐Art Platform for Probabilistic and Deterministic Seismic Hazard Assessment

Abstract: A new computational platform for seismic hazard assessment is presented. The platform, named SeismicHazard, allows characterizing the intensity, uncertainty, and likelihood of ground motions from subduction‐zone (shallow interface and intraslab) and crustal‐zone earthquakes, considering site‐specific as well as regional‐based assessments. The platform is developed as an object‐oriented MATLAB graphical user interface, and it features several state‐of‐the‐art capabilities for probabilistic and deterministic (scenario‐based) seismic hazard assessment. The platform integrates the latest developments in performance‐based earthquake engineering for seismic hazard assessment, including seismic zonation models, ground‐motion models (GMMs), ground‐motion correlation structures, and the estimation of design spectra (uniform hazard spectra, classical conditional mean spectrum (CMS) for a unique tectonic setting). In addition to these standard capabilities, the platform supports advanced features, not commonly found in existing seismic hazard codes, such as (a) computation of source parameters from earthquake catalogs, (b) vector‐probabilistic seismic hazard assessment, (c) hazard evaluation based on conditional GMMs and user‐defined GMMs, (d) uncertainty treatment in the median ground motions through continuous GMM distributions, (e) regional shaking fields, and (f) estimation of CMS considering multiple GMMs and multiple tectonic settings. The results from the platform have been validated against accepted and well‐documented benchmark solutions.

'Surfeiting, The Appetite May Sicken': Entrepreneurship and the Happiness of Nations

Abstract: We know that entrepreneurs - at least those driven by opportunities - can contribute to economic growth, productivity improvements and competitiveness in national economies.. But do they contribute to happiness on the country level? In other words, does the happiness of nations depend on its entrepreneurs? And what about happy nations - are they better places for entrepreneurs to start-up new businesses? In this paper we survey the literature on entrepreneurship and happiness, and use various data sources, including from the Global Entrepreneurship Monitor, to find tentative evidence of an inverse U-shape relationship between (opportunity) entrepreneurship and national happiness. We find little evidence that a nation's happiness drives early-stage entrepreneurial activity but we do find evidence that opportunity-motivated entrepreneurs in happier nations may be less concerned with high firm growth. Thus we conclude that opportunity-motivated entrepreneurship may contribute to a nation's happiness, but only up to a point. Not everybody should become entrepreneurs, and the happiness of a nation cannot be indefinitely increased by boosting the numbers of opportunity entrepreneurs.

IL17/IL17RA as a Novel Signaling Axis Driving Mesenchymal Stem Cell Therapeutic Function in Experimental Autoimmune Encephalomyelitis

Abstract: The therapeutic effect of mesenchymal stem cells (MSCs) in multiple sclerosis (MS) and the experimental autoimmune encephalomyelitis (EAE) model has been well described. This effect is, in part, mediated through the inhibition of IL17-producing cells and the generation of regulatory T cells. While proinflammatory cytokines such as IFNγ, TNFα, and IL1β have been shown to enhance MSCs immunosuppressive function, the role of IL17 remains poorly elucidated. The aim of this study was, therefore, to investigate the role of the IL17/IL17R pathway on MSCs immunoregulatory effects focusing on Th17 cell generation in vitro and on Th17-mediated EAE pathogenesis in vivo. In vitro, we showed that the immunosuppressive effect of MSCs on Th17 cell proliferation and differentiation is partially dependent on IL17RA expression. This was associated with a reduced expression level of MSCs immunosuppressive mediators such as VCAM1, ICAM1, and PD-L1 in IL17RA-/- MSCs as compared to wild-type (WT) MSCs. In the EAE model, we demonstrated that while WT MSCs significantly reduced the clinical scores of the disease, IL17RA-/- MSCs injected mice exhibited a clinical worsening of the disease. The disability of IL17RA-/- MSCs to reduce the progression of the disease paralleled the inability of these cells to reduce the frequency of Th17 cells in the draining lymph node of the mice as compared to WT MSCs. Moreover, we showed that the therapeutic effect of MSCs was correlated with the generation of classical Treg bearing the CD4+CD25+Foxp3+ signature in an IL17RA-dependent manner. Our findings reveal a novel role of IL17RA on MSCs immunosuppressive and therapeutic potential in EAE and suggest that the modulation of IL17RA in MSCs could represent a novel method to enhance their therapeutic effect in MS.