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CD46 is the main receptor for complement protein C3 and plays an important role in adaptive immune responses. CD46 genetic variants are associated with susceptibility to several infectious and autoimmune diseases. Additionally, CD46 function can be subverted by HIV-1 to evade attack by complement, a strategy shared by viruses of other families. We sought to determine the association between CD46 gene variants and HIV-1 acquired through intravenous drug use (IDU) and sexual routes (n = 823). Study subjects were of European ancestry and were HIV-1 infected (n = 438) or exposed but seronegative (n = 387). Genotyping of the rs2796265 SNP located in the CD46 gene region was done by allele-specific real-time PCR. A meta-analysis merging IDU and sexual cohorts indicates that the minor genotype (CC) was associated with increased resistance to HIV-1 infection OR = 0.2, 95% CI (0.07–0.61), p = 0.004. The HIV-1-protective genotype is correlated with reduced CD46 expression and alterations in the ratio of CD46 mRNA splicing isoforms.

The objective was to evaluate the accuracy of a single determination of IgM antibodies for hepatitis E virus (HEV) diagnosis in patients with acute hepatitis. A prospec tive study included patients with suspicion of HEV infection, defined as individuals with acute hepatitis showing negative results for serological and molecular markers of other hep atitis viruses. All patients were evaluated for hepatitis E virus infection, including both IgM antibodies and viral RNA determinations. Hepatitis E virus infection was defined as positivity for any of these markers. A total of 182 patients were included in the study, of whom 68 (37.4%) were diagnosed with HEV infection. Of these, 29 (42.6%) were positive for both IgM and HEV RNA, 25 (36.8%) were positive only for IgM antibodies, and 14 (20.6%) were posi tive only for HEV RNA. Considering only those individuals who were positive for IgM anti bodies, 54 of the 68 total cases (79.4%) could be identified, showing a percentage of false negative individuals of 20.6%. The diagnostic algorithm of hepatitis E virus infection in patients with acute hepatitis should include the determination of both IgM antibodies and HEV RNA because single sampling for IgM antibody determination led to an important pro portion of misdiagnosed cases.

The cortex, the outermost layer of the brain where most of the information is processed at a mesoscopic scale, is formed by cortical columns. These cortical columns are composed by neurons that organize in a cylindrical shape. The dynamical behavior of these columns can be modeled through neural mass models: physiologically plausible nonlinear mathematical models that represent the average dynamics of all the neurons inside them. In this work, a network of interacting cortical columns, each one of them modelled by the Jansen-Rit model, is presented with a set of connectivity parameters that determine the interactions between the columns. These parameters are tuned using a machine learning tool, genetic algorithms, which take inspiration from biological evolution, with the aim of learning to process a set of input signals that mimic sensory information. The results obtained show that the neural mass network built in this work is capable of learning different input signals and classifying them using synchronization of the dynamics of the neural mass models in the output layer., El córtex, la capa más externa del cerebro donde se procesa la mayor parte de la información a escala mesoscópica, está formado por columnas corticales. Estas están compuestas por neuronas que se organizan de forma cilíndrica. El comportamiento dinámico de estas columnas puede modelarse mediante modelos de masa neuronal: modelos matemáticos no lineales fisiológicamente plausibles que representan la dinámica media de todas las neuronas que se encuentran en su interior. En este trabajo se presenta una red de columnas corticales en interacción, cada una de ellas siguiendo el modelo Jansen-Rit, con un conjunto de parámetros de conectividad que determinan las interacciones entre las columnas. Estos parámetros se ajustan mediante una herramienta de aprendizaje automático: los algoritmos genéticos, que se inspiran en la evolución biológica, con el objetivo de aprender a procesar un conjunto de señales de entrada que imitan la información sensorial. Los resultados obtenidos muestran que la red construida en este trabajo es capaz de aprender diferentes señales de entrada y clasificarlas utilizando la sincronización de la dinámica de los modelos Jansen-Rit de la capa de salida., El còrtex, la capa més externa del cervell on es processa la major part de la informació a escala mesoscòpica, està format per columnes corticals. Aquestes estan compostes per neurones que s'organitzen de forma cilíndrica. El comportament dinàmic d'aquestes columnes es pot modelar mitjançant models de massa neuronal: models matemàtics no lineals fisiològicament plausibles que representen la dinàmica mitjana de totes les neurones que es troben al seu interior. En aquest treball es presenta una xarxa de columnes corticals en interacció, cadascuna d'elles seguint el model Jansen-Rit, amb un conjunt de paràmetres de connectivitat que determinen les interaccions entre les columnes. Aquests paràmetres s'ajusten mitjançant una eina d'aprenentatge automàtic: els algoritmes genètics, que s'inspiren en l'evolució biològica, amb l'objectiu d'aprendre a processar un conjunt de senyals d'entrada que imiten la informació sensorial. Els resultats obtinguts mostren que la xarxa construïda en aquest treball és capaç d'aprendre diferents senyals d'entrada i classificar-les utilitzant la sincronització de la dinàmica dels models Jansen-Rit de la capa de sortida.

Space plays a prominent role in virtually all animal behavior. In order to be able to navi-gate, several types of neurons involved in spatial navigation encode external space in distinctreference frames, with respect to the animal (egocentric) or with respect to external cues (al-locentric). Here, we sought to characterize the spatial correlates of large neural populationsand single-cells in awake, behaving mice using fluorescence calcium imaging. First, we cou-pled a wide-field microscope with a tracking system so that we could systematically recordspatial correlations in large-scale dynamics. Using this experimental paradigm, we didn?tidentify any underlying signal allocentric signal throughout cortex in the mesoscopic scale.Second, we studied single-cell dynamics in the retrosplenial cortex using 2-photon imagingand reported neural representations of boundaries in egocentric coordinates. Overall, thecurrent work provides a framework to study spatial correlates in distinc reference frames inboth single-cell and mesoscopic neural activity in behaving mice., El espacio juega un rol esencial en todo comportamiento animal. Con objetivo de poder navegar con éxito, el cerebro dispone de múltiples poblaciones neuronales que codifican el espai en dos sistemas de referencia diferente: alocéntrico, o respecto a elementos espaciales externos y egocéntrico, respecto al propio animal. En este trabajo se caracterizan las correlaciones espaciales de tanto circuitos neuronales en la escala mesoscópica como en neuronas individuales. Con tal objectivo, combinamos microscopia de modalidad wide-field con un sistema capaz de rastrear la posición del ratón mientras se desplaza por su entorno. Usando esta medologia, no idenfiticamos ninguna señal de carácter alocéntrico presente en escala mesoscópica. Seguidamente, usamos microscopía de dos fotones en el córtex retrosplenial y demostramos la existencia de neuronas que responden a los límites del entorno en coordenadas egocéntricas. Con todo, este trabajo propone metodologías que nos permiten estudiar las diveras representaciones neuronals que se encargan de codificar el espacio a nivel cerebral en ratones., L’espai juga un rol essencial en tot comportament animal. Per tal de poder navegar, diverses poblacions neuronals estan involucrades en codificar l’espai extern en diferents sistemes de referència: respecte a l’animal (egocèntric) o respecte a elements externs (alocèntric). Aquest treball s’ocupa de caracteritzar les correlaciones espaials de tant circuits neurones com de neurones individuals. Per fer-ho, primer hem combinat un microscopi de modalitat wide-field amb un sistema capaç de rastrejar la posició per tal de mesurar correlaciona espaials en tot el còrtex dorsal. Fent servir aquesta metodologia, no identifiquem cap senyal de caràcter alocèntric a l’escala mesoscòpica. Després, fem servir microscòpia de dos fotons i identifiquem neurones que responen als límits espaials en coordenades egocèntriques. Tot plegat, aquest treball proposa un metodologies per tal d’estudiar les diverses représentacions espaials presents en activitat neuronal en ratolins.

The objective was to evaluate the accuracy of a single determination of IgM antibodies for hepatitis E virus (HEV) diagnosis in patients with acute hepatitis. A prospective study included patients with suspicion of HEV infection, defined as individuals with acute hepatitis showing negative results for serological and molecular markers of other hepatitis viruses. All patients were evaluated for hepatitis E virus infection, including both IgM antibodies and viral RNA determinations. Hepatitis E virus infection was defined as positivity for any of these markers. A total of 182 patients were included in the study, of whom 68 (37.4%) were diagnosed with HEV infection. Of these, 29 (42.6%) were positive for both IgM and HEV RNA, 25 (36.8%) were positive only for IgM antibodies, and 14 (20.6%) were positive only for HEV RNA. Considering only those individuals who were positive for IgM antibodies, 54 of the 68 total cases (79.4%) could be identified, showing a percentage of false-negative individuals of 20.6%. The diagnostic algorithm of hepatitis E virus infection in patients with acute hepatitis should include the determination of both IgM antibodies and HEV RNA because single sampling for IgM antibody determination led to an important proportion of misdiagnosed cases.

Inferring the interactions between coupled oscillators is a significant open problem in complexity science, with multiple interdisciplinary applications. While the Kalman filter (KF) technique is a well-known tool, widely used for data assimilation and parameter estimation, to the best of our knowledge, it has not yet been used for inferring the connectivity of coupled chaotic oscillators. Here we demonstrate that KF allows reconstructing the interaction topology and the coupling strength of a network of mutually coupled Rössler-like chaotic oscillators. We show that the connectivity can be inferred by considering only the observed dynamics of a single variable of the three that define the phase space of each oscillator. We also show that both the coupling strength and the network architecture can be inferred even when the oscillators are close to synchronization. Simulation results are provided to show the effectiveness and applicability of the proposed method., This work was supported in part by Spanish Ministerio de Ciencia, Innovación y Universidades (PGC2018- 099443-B-I00), AGAUR FI scholarship (E.F.) and ICREA ACADEMIA (C. M.), Generalitat de Catalunya., Peer Reviewed, Postprint (published version)

Little is known about the role of ticks in maintaining highly prevalent zoonotic viruses in wildlife, such as hepatitis E virus (HEV), which do not require ticks for transmission between animals and humans. In this cross-sectional study, adult female ticks were collected from Eurasian wild boar (Sus scrofa) in autumn 2015 in Spain. HEV RNA in both ticks and wild boar was evaluated by RT-qPCR. Twenty-nine adult Hyalomma lusitanicum ticks were collected from 29 wild boars. HEV RNA was detected in a total of 10 tick (34.4%) and 11 wild boar serum samples (37.9%). In two cases, detectable HEV RNA was found in a wild boar but not in the tick collected from them. In contrast, one HEV-positive tick was collected from an HEV-negative wild boar. All viral sequences were consistent with genotype 3f. We describe for the first time the presence of HEV RNA in adult Hyalomma lusitanicum ticks.