Estudio de la respuesta dinámica de estructuras sumergidas en un fluido

Este proyecto se ha realizado con el objetivo de estudiar y comparar la respuesta dinámica cuando se sumerge cierta estructura en un fluido de alta densidad. Por una parte, se ha calculado la respuesta de la estructura en aire, caso que se ha considerado como vacío, y en agua. Por otra parte, la estructura completa correspondiente a un conjunto formado por un eje acoplado a un disco se ha descompuesto en sus dos estructuras más simples, para estudiarlas por separado y luego acopladas, para así poder analizar la influencia que estas tienen sobre el conjunto. El estudio se ha centrado en la obtención de diferentes propiedades modales, concretamente las frecuencias naturales y los modos de vibración. La metodología escogida para realizar este trabajo ha sido mediante la simulación numérica computacional con el software ANSYS mediante el método de los elementos finitos, donde primeramente se ha realizado un análisis de la sensibilidad del mallado para poder asegurar la precisión del modelo. Se han realizado dos tipos de cálculos: el análisis modal estructural, en el cual las estructuras se modelan como si estuvieran en el vacío; y el análisis modal acústico, en el que se las estructuras se modelan rodeadas de elementos acústicos que simulan que están sumergidas en agua. Una vez calculados los modos de vibración en las diferentes condiciones, se han comparado los resultados entre ellos mediante el ratio de reducción de la frecuencia para poder sacar conclusiones de la interacción fluido estructura y la masa agregada. También, se han analizado los efectos del acoplamiento entre eje y disco, incluyendo la influencia que tiene en los parámetros modales soportar el eje en diferentes posiciones donde se deberían instalar rodamientos para poner el sistema en rotación. Los resultados obtenidos han sido representativos de los efectos esperados al principio del proyecto. Por una parte, se ha observado que las frecuencias naturales son menores si se sumerge en agua la estructura. Esto es debido al efecto de la masa agregada que debe ser desplazada cuando el fluido que rodea a la estructura no es aire y tiene una elevada densidad. También, se ha observado que este efecto no afecta de la misma manera a los diferentes componentes de la estructura debido a la geometría particular de cada parte. Por último, se ha observado que también existe una cierta diferencia en las frecuencias y modos de vibración según si se analiza la estructura acoplada o si se analizan sus partes por separado

Isoenzymatic characterization of Phlebotomus ariasi and P. perniciosus of canine leishmaniasis foci from Eastern Pyrenean regions and comparison with other populations from Europe.

An entomological survey was carried out in 2007 in two Pyrenean counties of Lleida province (northeastern Spain), where cases of autochthonous canine leishmaniasis have been recently reported. Phlebotomus ariasi and P. perniciosus, vectors of Leishmania infantum in the Mediterranean area, were captured. The aim of the present study was to compare these phlebotomine populations with others captured in known leishmaniasis foci in Europe. Populations of these species were studied by analysing the polymorphism of seven enzymatic systems (HK, PGI, PGM, MDH, 6PGD, FUM and ACO) and compared with other specimens from endemic regions of France, Italy, Malta, Portugal and Spain captured in other campaigns, and also with previously published results. Phlebotomus ariasi was more polymorphic than P. perniciosus. Only the ACO locus had diagnostic alleles, but some other alleles show high characteristic frequencies for each species. The neighbourjoining trees separated two population groups in both species. On the basis of the isoenzyme study results, sand fly populations of the Pyrenean region in Lleida province are closely related to those of other nearby leishmaniasis endemic regions in France and Spain

Is leishmaniosis spreading to northern areas of the Iberian Peninsula? The examples of Lleida (NE Spain) and Andorra

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/46988The entomological and canine leishmaniosis surveys carried out in the northwest of Catalonia and in Andorra in the context of the European project Emerging Diseases in a changing European eNvironment (EDEN) are summarized. The aim of the study was to obtain data on the presence of leishmaniosis in these areas and the spatial distribution of their vectors

Introducing automation to the molecular diagnosis of Trypanosoma cruzi infection: A comparative study of sample treatments, DNA extraction methods and real-time PCR assays

Background Polymerase chain reaction (PCR) has become a useful tool for the diagnosis of Trypanosoma cruzi infection. The development of automated DNA extraction methodologies and PCR systems is an important step toward the standardization of protocols in routine diagnosis. To date, there are only two commercially available Real-Time PCR assays for the routine laboratory detection of T. cruzi DNA in clinical samples: TCRUZIDNA.CE (Diagnostic Bioprobes Srl) and RealCycler CHAG (Progenie Molecular). Our aim was to evaluate the RealCycler CHAG assay taking into account the whole process. Methodology/Principal findings We assessed the usefulness of an automated DNA extraction system based on magnetic particles (EZ1 Virus Mini Kit v2.0, Qiagen) combined with a commercially available Real-Time PCR assay targeting satellite DNA (SatDNA) of T. cruzi (RealCycler CHAG), a methodology used for routine diagnosis in our hospital. It was compared with a well-known strategy combining a commercial DNA isolation kit based on silica columns (High Pure PCR Template Preparation Kit, Roche Diagnostics) with an in-house Real-Time PCR targeting SatDNA. The results of the two methodologies were in almost perfect agreement, indicating they can be used interchangeably. However, when variations in protocol factors were applied (sample treatment, extraction method and Real-Time PCR), the results were less convincing. A comprehensive fine-tuning of the whole procedure is the key to successful results. Guanidine EDTA-blood (GEB) samples are not suitable for DNA extraction based on magnetic particles due to inhibition, at least when samples are not processed immediately. Conclusions/Significance This is the first study to evaluate the RealCycler CHAG assay taking into account the overall process, including three variables (sample treatment, extraction method and Real-Time PCR). Our findings may contribute to the harmonization of protocols between laboratories and to a wider application of Real-Time PCR in molecular diagnostic laboratories associated with health centers.Fil: Abras, Alba. Universidad de Barcelona; España. Universidad de Girona; España. Instituto de Salud Global de Barcelona; EspañaFil: Ballart, Cristina. Universidad de Barcelona; España. Instituto de Salud Global de Barcelona; EspañaFil: Llovet, Teresa. Universitat Autònoma de Barcelona; España. Hospital de la Santa Creu I Sant Pau; EspañaFil: Roig, Carme. Hospital de la Santa Creu I Sant Pau; EspañaFil: Gutiérrez, Cristina. Hospital de la Santa Creu I Sant Pau; EspañaFil: Tebar, Silvia. Universidad de Barcelona; España. Instituto de Salud Global de Barcelona; EspañaFil: Berenguer, Pere. Hospital de la Santa Creu I Sant Pau; EspañaFil: Pinazo, María-Jesús. Instituto de Salud Global de Barcelona; EspañaFil: Posada, Elizabeth. Instituto de Salud Global de Barcelona; EspañaFil: Gascón, Joaquim. Instituto de Salud Global de Barcelona; EspañaFil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Gállego, Montserrat. Instituto de Salud Global de Barcelona; España. Universidad de Barcelona; EspañaFil: Muñoz, Carmen. Hospital de la Santa Creu I Sant Pau; España. Universitat Autònoma de Barcelona; Españ

Factors influencing the presence of sand flies in Majorca (Balearic Islands, Spain) with special reference to Phlebotomus pernicious, vector of Leishmania infantum

Background: Although the Mediterranean island of Majorca is an endemic area of leishmaniosis, there is a lack of up-to-date data on its sand fly fauna, the last report dating from 1989. The aim of the present study was to provide information on the current sand fly distribution, the potential environmental factors favoring the presence of Phlebotomus perniciosus and which areas are at risk of leishmaniosis. Methods: In July 2008 sand fly captures were carried out in Majorca with sticky castor oil interception traps. The capture stations were distributed in 77 grids (5x5 km2) covering the entire island. A total of 1,882 sticky traps were set among 111 stations. The characteristics of the stations were recorded and maps were designed using ArcGIS 9.2 software. The statistical analysis was carried out using a bivariate and multivariate logistic regression model. Results: The sand fly fauna of Majorca is composed of 4 species: Phlebotomus perniciosus, P sergenti, P. papatasi and Sergentomyia minuta. P. perniciosus, responsible for Leishmania infantum transmission, was captured throughout the island (frequency 69.4 %), from 6 to 772 m above sea level. Through logistic regression we estimated the probability of P. perniciosus presence at each sampling site as a function of environmental and meteorological factors. Although in the initial univariate analyses the probability of P. perniciosus presence appeared to be associated with a wide variety of factors, in the multivariate logistic regression model only altitude, settlement, aspect, drainage hole construction, adjacent flora and the proximity of a sheep farm were retained as positive predictors of the distribution of this species. Conclusions: P. perniciosus was present throughout the island, and thereby the risk of leishmaniosis transmission. The probability of finding P. perniciosus was higher at altitudes ranging from 51 to 150 m.a.s.l., with adjacent garrigue shrub vegetation, at the edge of or between settlements, and in proximity to a sheep farm

Importance of individual analysis of environmental and climatic factors affecting the density of Leishmania vectors living in the same geographical area: the example of Phlebotomus ariasi and P. perniciosus in northeast Spain.

The aim of the present study was to determine the role of specific environmental and climatic factors affecting the distribution and density of Phlebotomus ariasi and P. perniciosus, the proven vectors for Leishmania infantum in Spain. An entomological study was carried out in July 2006 in the province of Lleida with sticky traps set in their diurnal resting places at altitudes ranging from 86 to 1,755 m above the mean sea level (339 sites were sampled). Bivariate analysis revealed that factors such as altitude, bioclimatic zone, temperature, precipitation, sampling site (site relative to settlement, site situation, site category), wall vegetation, particular environment (in this case a natural park), general environment, adjacent natural vegetation and land cover were significantly associated with sand fly densities. The multivariate model for P. perniciosus revealed that its density was affected by site and land cover. Specifically, paved driveways correlated negatively with vector density (Incidence Risk Ratio (IRR): 0.41) and arable land cover correlated positively (IRR: 4.59). In the case of P. ariasi, a significant correlation was observed with the altitude and bioclimatic zone, with density increasing at >800 m above the mean sea level (IRR: 3.40) and decreasing in the meso-Mediterranean bioclimatic zone (IRR: 0.08). Both species were mostly found in agricultural and forest areas far from domestic environments. However, the two species correlated differently with altitude, bio-climate, vegetation, temperature and precipitation, which emphasises the importance of their individual analysis in studies regarding risk of leishmaniasis transmission

Predicting the distribution of canine leishmaniasis in western Europe based on environmental variables.

The domestic dog is the reservoir host of Leishmania infantum, the causative agent of zoonotic visceral leishmaniasis endemic in Mediterranean Europe. Targeted control requires predictive risk maps of canine leishmaniasis (CanL), which are now explored. We databased 2187 published and unpublished surveys of CanL in southern Europe. A total of 947 western surveys met inclusion criteria for analysis, including serological identification of infection (504, 369 dogs tested 1971-2006). Seroprevalence was 23 2% overall (median 10%). Logistic regression models within a GIS framework identified the main environmental predictors of CanL seroprevalence in Portugal, Spain, France and Italy, or in France alone. A 10-fold cross-validation approach determined model capacity to predict point-values of seroprevalence and the correct seroprevalence class (20%). Both the four-country and France-only models performed reasonably well for predicting correctly the 20% seroprevalence classes (AUC >0 70). However, the France-only model performed much better for France than the four-country model. The four-country model adequately predicted regions of CanL emergence in northern Italy (<5% seroprevalence). Both models poorly predicted intermediate point seroprevalences (5-20%) within regional foci, because surveys were biased towards known rural foci and Mediterranean bioclimates. Our recommendations for standardizing surveys would permit higher-resolution risk mapping

Current status of Leishmaniosis in the Balearic Islands

Podeu consultar el llibre complet a: http://hdl.handle.net/2445/103042Data on leishmaniosis and its vectors (sand flies) in the Balearic Islands are scarce and restricted mainly to Majorca. According to the official data, the overall rate of human leishmaniosis (HL) is 0.7-3.5 cases per year/100,000 inhabitants (for the period 2001-2015), and the reported prevalence of canine leishmaniosis (CanL) varies between 0 and 45%, depending on the island and the dog population tested. In the present study, we investigated the sand fly fauna and current status of CanL in the Balearic Islands. Four sand fly species were captured: Phlebotomus perniciosus, a known vector in the Mediterranean area, P. sergenti, P. papatasi and Sergentomyia minuta. P. perniciosus was found throughout the island of Majorca, from sea level to the mountains, being detected in 70% of the capture sites and with a density of 6.7 specimens/m2. The global density of P. perniciosus in Minorca was of 3.4 specimens/m2, which constitutes a significant decrease compared to the results of a previous study performed 20 years ago. The influence of environmental factors on the presence or density of P. perniciosus differed according to the physiography of the area studied. A standard questionnaire sent to the local veterinarians in the Balearic Islands revealed that 73.8% of veterinarians had confirmed CanL cases in the previous 12 months and thought the disease was increasing in Minorca. The global seroprevalence of CanL in Minorca was 24%, being 31% among animals who had never left the island, which shows the existence of an autochthonous focus of CanL unrelated with an increasing vector density

Plasma-Derived Extracellular Vesicles as Potential Biomarkers in Heart Transplant Patient with Chronic Chagas Disease

Chagas disease is emerging in countries to which it is not endemic. Biomarkers for earlier therapeutic response assessment in patients with chronic Chagas disease are needed. We profiled plasma-derived extracellular vesicles from a heart transplant patient with chronic Chagas disease and showed the potential of this approach for discovering such biomarkers.Barcelona Institute for Global Health (ISGlobal) receives support from the Spanish Ministry of Science, Innovation and Universities through the Centro de Excelencia Severo Ochoa 2019–2023 Program (CEX2018-000806-S). ISGlobal and Institut d’Investigació en Ciències de la Salut Germans Trias i Pujol (IGTP) are members of the Centres de Recerca de Catalunya (CERCA Program), Generalitat de Catalunya. Work in the laboratory of C.F.B. is funded by Fundació La Marató de TV3 (reference 566/U/2018) and Fundación Mundo Sano. This project was co-financed by the European Union through the European Regional Development Fund with the support of Secretaria d’Universitats i Recerca del Departament d’Empresa i Coneixement de la Generalitat de Catalunya. N.C., M.G., J.G., and M.J.P. receive funds from the Redes temáticas de investigación cooperativa en salud (RETICS), Spanish Tropical Diseases Network “RD12/0018/0010” and from the Agencia de Gestió d’Ajuts Universitaris i de Recerca, Generalitat de Catalunya; grant “2017 SGR 00924.” M.G., C.B., J.G., M.J.P., and I.C.A. belong to the Ibero-American Nuevas Herramientas para el Diagnóstico y la Evaluación del Paciente con Enfermedad de Chagas network. I.C.A. is partially supported by grants no. 2G12MD007592 and 5U54MD007592 from the National Institute on Minority Health and Health Disparities of the US National Institutes of Health. We are grateful to the Biomolecule Analysis Core Facility at University of Texas at El Paso, Border Biomedical Research Center, funded by National Institute on Minority Health and Health Disparities grants 2G12MD007592 and 5U54MD007592. M.T.M. received a PhD fellowship from the Science Without Borders Program, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil.S