HIV-1 infection of microglial cells in a reconstituted humanized mouse model and identification of compounds that selectively reverse HIV latency.

Most studies of HIV latency focus on the peripheral population of resting memory T cells, but the brain also contains a distinct reservoir of HIV-infected cells in microglia, perivascular macrophages, and astrocytes. Studying HIV in the brain has been challenging, since live cells are difficult to recover from autopsy samples and primate models of SIV infection utilize viruses that are more myeloid-tropic than HIV due to the expression of Vpx. Development of a realistic small animal model would greatly advance studies of this important reservoir and permit definitive studies of HIV latency. When radiation or busulfan-conditioned, immune-deficient NSG mice are transplanted with human hematopoietic stem cells, human cells from the bone marrow enter the brain and differentiate to express microglia-specific markers. After infection with replication competent HIV, virus was detected in these bone marrow-derived human microglia. Studies of HIV latency in this model would be greatly enhanced by the development of compounds that can selectively reverse HIV latency in microglial cells. Our studies have identified members of the CoREST repression complex as key regulators of HIV latency in microglia in both rat and human microglial cell lines. The monoamine oxidase (MAO) and potential CoREST inhibitor, phenelzine, which is brain penetrant, was able to stimulate HIV production in human microglial cell lines and human glial cells recovered from the brains of HIV-infected humanized mice. The humanized mice we have developed therefore show great promise as a model system for the development of strategies aimed at defining and reducing the CNS reservoir

Bolo de amiodarona como profilaxis de la FA postoperatoria en pacientes sometidos a recambio valvular

La fibrilación auricular es la arritmia con consecuencias clínicas significativas más común en el postoperatorio. Se estima que la incidencia de fibrilación auricular postoperatoria (FAP) en cirugía extratorácica es cercana al 10%, entre el 3% y el 30% en cirugía torácica no cardíaca y entre el 16% y el 46% en el de cirugía cardíaca. La FAP se asocia con una mayor tasa de morbimortalidad perioperatoria, aumentando la estancia y los costes hospitalarios. Las consecuencias clínicas de la FAP son importantes, pudiendo ocasionar deterioro hemodinámico grave, evento embólico cerebral, o evolución a otras arritmias ventriculares. Son diversos los métodos empleados, tanto farmacológicos como no farmacológicos, encaminados al mantenimiento del ritmo sinusal normal en el postoperatorio de cirugía cardíaca, siendo la prevención y el correcto tratamiento de la FAP un objetivo prioritario en el pacientes quirúrgico

Free hardware based system for air quality and CO2 monitoring

Due to the increase in air pollution, especially in Latin American countries of low and middle income, great environmental and health risks have been generated, highlighting that there is more pollution in closed environments. Given this problem, it has been proposed to develop a system based on free hardware for monitoring air quality and CO2, in order to reduce the levels of air pollution in a closed environment, improving the quality of life of people and contributing to the awareness of the damage caused to the environment by the hand of man himself. The system is based on V-Model, complemented with a ventilation prototype implemented with sensors and an application for its respective monitoring. The sample collected in the present investigation was non-probabilistic, derived from the reports of air indicators during 15 days with specific schedules of 9am, 1pm and 6pm. The results obtained indicated that the air quality decreased to 670 ppm, as well as the collection time decreased to 5 seconds and finally the presence of CO2 was reduced to 650 ppm after the implementation of the system, achieving to be within the standards recommended by the World Health Organization

Geophysical data integration for a joint interpretation in a shallow gypsiferous context

As every geophysical technique suffers from its own limitation, a proper survey has to combine different geophysical methods. The integration of different geophysical data in order to derive a joint geological interpretation is complicated beyond qualitative (subjective) correlations. We propose a new numerical method (less subjective) to integrate three separated datasets: seismics, electrics and well logging. The study area is the shallow subsurface of a planned singular facility in Villar de Cañas (Cuenca, Central Spain). Lithology down to 100 m deep consists of a transition from shale to massive gypsum. In 2013, we acquired a3D Traveltime Tomography to characterize this transition. After data processing, the velocity model showed, in general, a good correlation with geological profiles, being able to identify the three main layers: shales, transition gypsum and massive gypsum. The correlation for the massive gypsum limit (high velocity contrast) is very good, but is not that good for the transition shale-gypsum (low velocity contrast).Research supports: CGL2014-56548-P, 2009-SGR-1595 , CGL2013-47412-C2-1-PPeer Reviewe

Performance of mixed formulations for the particle finite element method in soil mechanics problems

This paper presents a computational framework for the numerical analysis of fluid-saturated porous media at large strains. The proposal relies, on one hand, on the particle finite element method (PFEM), known for its capability to tackle large deformations and rapid changing boundaries, and, on the other hand, on constitutive descriptions well established in current geotechnical analyses (Darcy’s law; Modified Cam Clay; Houlsby hyperelasticity). An important feature of this kind of problem is that incompressibility may arise either from undrained conditions or as a consequence of material behaviour; incompressibility may lead to volumetric locking of the low-order elements that are typically used in PFEM. In this work, two different three-field mixed formulations for the coupled hydromechanical problem are presented, in which either the effective pressure or the Jacobian are considered as nodal variables, in addition to the solid skeleton displacement and water pressure. Additionally, several mixed formulations are described for the simplified single-phase problem due to its formal similitude to the poromechanical case and its relevance in geotechnics, since it may approximate the saturated soil behaviour under undrained conditions. In order to use equal-order interpolants in displacements and scalar fields, stabilization techniques are used in the mass conservation equation of the biphasic medium and in the rest of scalar equations. Finally, all mixed formulations are assessed in some benchmark problems and their performances are compared. It is found that mixed formulations that have the Jacobian as a nodal variable perform better.Peer ReviewedPostprint (author's final draft

Numerical simulation of penetration problems in geotechnical engineering with the particle finite element method (PFEM)

This paper highlights a computational framework for the numerical analysis of saturated soil-structure interaction problems. The variational equations of linear momentum and mass balance are obtained for the large deformation case. These equations are solved using the Particle Finite Element Method. The paper concludes with a benchmark test and the analysis of a penetration test

Interprétation améliorée des essais de pénétration au cône par la méthode des éléments finis des particules (PFEM)

The paper presents an enhanced interpretation of the cone penetration test based on numerical analysis performed using the Particle Finite Element Method (PFEM). This method allows the incorporation of strong non-linearities, notably those associated with the large displacements and strains arising from the process of the penetration of the cone. Realistic constitutive laws can also been used. Undrained CPT tests are analysed using a single phase formulation whereas CPTu tests are examined using a two-phase formulation that allows the computation of pore pressures and the study of partially drained tests. It can be concluded that PFEM provides an efficient and robust method to analyse insertion problems that are ubiquitous in geotechnical engineering.Postprint (published version

Coupled effective stress analysis of insertion problems in geotechnics with the Particle Finite Element Method

This paper describes a computational framework for the numerical analysis of quasi-static soil-structure insertion problems in water saturated media. The Particle Finite Element Method is used to solve the linear momentum and mass balance equations at large strains. Solid-fluid interaction is described by a simplified Biot formulation using pore pressure and skeleton displacements as basic field variables. The robustness and accuracy of the proposal is numerically demonstrated presenting results from two benchmark examples. The first one addresses the consolidation of a circular footing on a poroelastic soil. The second one is a parametric analysis of the cone penetration test (CPTu) in a material described by a Cam-clay hyperelastic model, in which the influence of permeability and contact roughness on test results is assessed.Peer ReviewedPostprint (author's final draft