Caracterización de las dianas terapéuticas FeSODs y TryR de Leishmania infantum y desarrollo de un ensayo de cuantificación de amastigotes intracelulares por citometría de flujo

as leishmaniasis son varias enfermedades causadas por la infección con parásitos del género Leishmania tras la picadura de un flebótomo infectado. Se estima que 350 millones de personas están en riesgo de contraer leishmaniasis, dándose entre 700.000 y 1 millón de casos nuevos de leishmaniasis humana al año. Los graves inconvenientes que presentan las opciones terapéuticas actuales hacen necesaria la búsqueda de nuevos fármacos. Las estrategias que emplea el parásito para sobrevivir a la interacción con su célula hospedadora, el macrófago, son una fuente de dianas terapéuticas, entre las que destacan las enzimas implicadas en la defensa frente al estrés oxidativo. Dentro de éstas, las cuatro superóxido dismutasas de hierro (FeSODs) del parásito, pese a haber sido demostrada su esencialidad para la supervivencia del parásito, han sido muy poco estudiadas. En este trabajo se han aislado y caracterizado bioquímicamente por primera vez versiones recombinantes, estables y activas del conjunto completo de estas enzimas. Además, se ha evaluado la posibilidad de utilizar la interfaz de dimerización de una de ellas como diana. Otra enzima implicada en la defensa frente al estrés oxidativo esencial para el parásito es la tripanotión reductasa (TryR). En este trabajo, se ha estudiado la inhibición que presenta esta enzima por uno de sus sustratos. Por otro lado, debido a los diversos inconvenientes que presentan los ensayos existentes para la determinación del contenido de parásitos intracelulares, en la presente memoria se describe un nuevo ensayo de cuantificación de la infección por amastigotes intracelulares que destaca por requerir poca manipulación humana y por no emplear equipamiento de imagen de alto contenido, que es caro y está poco extendido. Finalmente, se ha analizado la capacidad inhibitoria de tres metalodendrímeros sobre las FeSODs y la TryR de L. infantum, así como su potencial como leishmanicida

Continuous CaO/Ca(OH)2 Fluidized Bed Reactor for Energy Storage: First Experimental Results and Reactor Model Validation

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Industrial and Engineering Chemistry Research, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.iecr.6b04105Novel thermochemical energy storage systems that employ fluidized beds of CaO/Ca(OH)2 for hydration/dehydration reactions are under development because of the inherent advantages of the low cost of the materials and their relatively high temperature operation windows (450 °C–550 °C). We report in this work the results of the first steady state experiments conducted in a new pilot plant designed to test the concept under realistic reactor conditions. The pilot has a fluidized bed reactor with an internal diameter of 0.108 m and a height of 780 mm fed continuously with gas and solids as well as heat exchangers to supply/extract the required reaction heat. The experimental results during dynamic and steady state periods were fitted to a KL reactor bubbling bed model, using kinetic parameters from thermogravimetric studies and a single crossflow factor. The resulting continuous reactor model will serve as useful tool for the continued scaling up of this technology.Financial support provided by the European Commission under the 7th Framework Program (StoRRe Project GA 282677) is acknowledged.Peer reviewe

The yeast mitogen-activated protein kinase Slt2 is involved in the cellular response to genotoxic stress

BackgroundThe maintenance of genomic integrity is essential for cell viability. Complex signalling pathways (DNA integrity checkpoints) mediate the response to genotoxic stresses. Identifying new functions involved in the cellular response to DNA-damage is crucial. The Saccharomyces cerevisiae SLT2 gene encodes a member of the mitogen-activated protein kinase (MAPK) cascade whose main function is the maintenance of the cell wall integrity. However, different observations suggest that SLT2 may also have a role related to DNA metabolism.ResultsThis work consisted in a comprehensive study to connect the Slt2 protein to genome integrity maintenance in response to genotoxic stresses. The slt2 mutant strain was hypersensitive to a variety of genotoxic treatments, including incubation with hydroxyurea (HU), methylmetanosulfonate (MMS), phleomycin or UV irradiation. Furthermore, Slt2 was activated by all these treatments, which suggests that Slt2 plays a central role in the cellular response to genotoxic stresses. Activation of Slt2 was not dependent on the DNA integrity checkpoint. For MMS and UV, Slt2 activation required progression through the cell cycle. In contrast, HU also activated Slt2 in nocodazol-arrested cells, which suggests that Slt2 may respond to dNTP pools alterations. However, neither the protein level of the distinct ribonucleotide reductase subunits nor the dNTP pools were affected in a slt2 mutant strain. An analysis of the checkpoint function revealed that Slt2 was not required for either cell cycle arrest or the activation of the Rad53 checkpoint kinase in response to DNA damage. However, slt2 mutant cells showed an elongated bud and partially impaired Swe1 degradation after replicative stress, indicating that Slt2 could contribute, in parallel with Rad53, to bud morphogenesis control after genotoxic stresses.ConclusionsSlt2 is activated by several genotoxic treatments and is required to properly cope with DNA damage. Slt2 function is important for bud morphogenesis and optimal Swe1 degradation under replicative stress. The MAPK Slt2 appears as a new player in the cellular response to genotoxic stresses

Validación experimental de una pinza de dos dedos retráctiles

This paper presents analytical, numerical, and experimental testing models for designing and validating the feasibility of a gripper with two retractable fingers. The proposed gripper is specifically developed for grasping and manipulating objects that should be kept into restricted areas such as explosives, radioactive/ionized materials, and infected biological material specimens. The proposed gripper fingers can be retracted to pass through openings or slots and, once inside the restricted area, can be deployed in order to manipulate the objects without risk for the human operators. Analytical and numerical simulations are used to properly design and build a gripper prototype. Then, experimental tests are carried out to grasp objects of different sizes ranging from 5 to 10 mm. The obtained results are used to validate the gripper"s performance in terms of successful grasp and suitable accelerations and grasp forces

Automatic Expanding Mandrel with Air Sensing Device: Design and Analysis

In precision machining, expanding mandrels are used for jobs with close tolerances. An expanding mandrel consists of a tapered arbor or shaft, with a thin-slotted clamping sleeve or collet made of hardened steel. The internal tapered and external cylindrical surfaces are ground to a high degree of accuracy, and the mandrel expands to fit the internal bore of the workpiece. Expanding mandrels are, essentially, wedge mechanisms. This paper proposes an automatic expanding mandrel with a novel force transmission system for high stiffness within a novel air sensing system, which allows detection of the correct part position before starting machining. A computational model for determining the dynamic clamping force of the proposed mechanism is developed and implemented using MATLAB. This model considers the influence of the sti ness behaviors of the collet, force transmission structure and workpiece. Additionally, this paper presents the finite element method analyses which were conducted to check the proposed computational model. The amount of clamping force transmitted by a collet chuck holder depends strongly on: clearances, wedge angle, stiffness of the collet chuck holder and workpiece stiffness

Through the looking-glass with ALICE into the quark-gluon plasma: A new test for hadronic interaction models used in air shower simulations

Recently, the ALICE Collaboration reported an enhancement of the yield ratio of strange and multi-strange hadrons to charged pions as a function of multiplicity at mid-rapidity in proton-proton, proton-lead, lead-lead, and xenon-xenon scattering. ALICE observations provide a strong indication that a quark-gluon plasma is partly formed in high multiplicity events of both small and large colliding systems. Motivated by ALICE’s results, we propose a new test for hadronic interaction models used for analyzing ultra-highenergy-cosmic-ray (UHECR) collisions with air nuclei. The test is grounded in the almost equal columnenergy density in UHECR-air collisions and lead-lead collisions at the LHC. We applied the test to postLHC event generators describing hadronic phenomena of UHECR scattering and show that these QCD Monte Carlo-based codes must be retuned to accommodate the strangeness enhancement relative to pions observed in LHC data.Fil: Anchordoqui, Luis A.. American Museum of Natural History; Estados Unidos. City University of New York; Estados UnidosFil: García Canal, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Sciutto, Sergio Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Soriano, Jorge F.. City University of New York; Estados Unido

The Impact of Enforcement Capabilities on the Effectiveness of Public Assessment on Occupational Safety

número del art. 6426(1) Objective: The objective of this study was to evaluate the effect of enforcement capabilities on the efficacy of two public interventions to improve occupational safety in olive mills. (2) Method: The difference in efficacy was evaluated by comparing the risks detected in two groups in an initial assessment (with visits in the 2006–2008 period) to the risks detected in a later assessment, either after an intervention by Authorized Technicians with enforcement capabilities or after an intervention by Technical Advisors without enforcement capabilities (2011–2013). The assessments identified risks in the companies, according to a specific risk map for olive oil mill enterprises. (3) Results: Statistically significant differences were observed in the comparison of the risk reductions of the two groups, with regard to the initial assessment. The greatest reductions in risk were found in the companies that received interventions by Authorized Technicians with enforcement capabilities, in the sections of individual protection equipment and the storage of dangerous products. (4) Conclusion: Interventions by Authorized Technicians with enforcement capabilities are more effective than interventions by Technical Advisors without enforcement capabilities

Through the looking-glass with ALICE into the quark-gluon plasma: a new test for hadronic interaction models used in air shower simulations

Recently, the ALICE Collaboration reported an enhancement of the yield ratio of strange and multi-strange hadrons to charged pions as a function of multiplicity at mid-rapidity in proton-proton, proton-lead, lead-lead, and xenon-xenon scattering. ALICE observations provide a strong indication that a quark-gluon plasma is partly formed in high multiplicity events of both small and large colliding systems. Motivated by ALICE’s results, we propose a new test for hadronic interaction models used for analyzing ultra-high-energy-cosmic-ray (UHECR) collisions with air nuclei. The test is grounded in the almost equal column-energy density in UHECR-air collisions and lead-lead collisions at the LHC. We applied the test to post-LHC event generators describing hadronic phenomena of UHECR scattering and show that these QCD Monte Carlo-based codes must be retuned to accommodate the strangeness enhancement relative to pions observed in LHC data.Instituto de Física La Plat

Work accidents. ACSOM a new orientation for automatic risk management

Fundamento. Analizar la accidentalidad laboral en todo tipo de empresas, a través de los riesgos que la provocan, teniendo en cuenta que el objetivo final es establecer una clasificación de riesgos prioritarios. Esta información permite abordar las acciones preventivas oportunas sobre los riesgos más vulnerables. Material y Métodos. Se aplica un conjunto de técnicas estadístico-matemáticas, basadas fundamentalmente en contrastes estadísticos, a los accidentes laborales acaecidos durante tres años, en un organismo de investigación y desarrollo español (I+D) con 8.780 trabajadores. Se utiliza como patrón de referencia en este estudio, para un análisis comparativo, el conjunto de accidentes en España durante un periodo de 11 años. Resultados. Tras la aplicación de la nueva metodología, los dos primeros riesgos que requieren acciones preventivas prioritarias son interacción con substancias agresivas y accidentes con maquinaria móvil. Si únicamente se hubieran considerado los dos riesgos con frecuencias más elevadas, sin tener en cuenta la vulnerabilidad de cada uno de ellos, los riesgos prioritarios hubieran sido sobreesfuerzos y caídas al mismo nivel. Conclusiones. El análisis proporciona una relación de los riesgos más vulnerables (puntos débiles), sobre los cuales actuar y de esta forma ser más efectivos a la hora de reducir la accidentalidad.Background. To analyse workplace accidents, by considering the risks that provoke such accidents. hearing in mind that the final aim is to establish a classification of priority risks. This information will make it possible to undertake the opportune preventive actions against the most vulnerable risks. Material and Methods. A set of statistical-mathematical techniques, essentially based on statistical contrasts, was applied to work accidents taking place during a three year period in it Spanish Research and Development (R+D) organisation with 8, 780 workers. The reference standard used for comparative analysis was the ensemble of accidents in Spain over all 11 year period. Results. After application of the new methodology, the two risks requiring priority preventive actions are interaction with aggressive substances and accidents with moving machinery. If the two risks with the highest frequency had been considered alone, without taking into account the vulnerability of each, the priority risks would have been overexertion and falls at the same level. Conclusions. The analysis provides a list of the most vulnerable risks accidents on which action should be taken and thus achieve greater effectiveness in establishing which actions should be considered opportune

Pyridazino-pyrrolo-quinoxalinium salts as highly potent and selective leishmanicidal agents targeting trypanothione reductase

Fifteen pyridazino-pyrrolo-quinoxalinium salts were synthesized and tested for their antiprotozoal activity against Leishmania infantum amastigotes. Eleven of them turned out to be leishmanicidal, with EC50 values in the nanomolar range, and displayed low toxicity against the human THP-1 cell line. Selectivity indices for these compounds range from 10 to more than 1000. Compounds 3b and 3f behave as potent inhibitors of the oxidoreductase activity of the essential enzyme trypanothione disulfide reductase (TryR). Interestingly, binding of 3f is not affected by high trypanothione concentrations, as revealed by the noncompetitive pattern of inhibition observed when tested in the presence of increasing concentrations of this substrate. Furthermore, when analyzed at varying NADPH concentrations, the characteristic pattern of hyperbolic uncompetitive inhibition supports the view that binding of NADPH to TryR is a prerequisite for inhibitor-protein association. Similar to other TryR uncompetitive inhibitors for NADPH, 3f is responsible for TryR-dependent reduction of cytochrome c in a reaction that is typically inhibited by superoxide dismutase.Comunidad de MadridMinisterio de Economía y CompetitividadMinisterio de Ciencia, Innovación y Universidade