Interacción entre el sistema endocannabinoide y el sistema esfingosina-1-fosfato en cerebro de rata

[ES] El sistema endocannabinoide (eCB) y el sistema esfingosina-1-fosfato (S1P) son sistemas de señalización implicados en multitud de procesos fisiológicos y patológicos. Concretamente en el cerebro ambos sistemas regulan la actividad neuronal. Dada la similitud de ambos sistemas a varios niveles se ha postulado que estos interaccionan de alguna forma. En este trabajo se presentan las evidencias existentes hasta la fecha de que existe dicha interacción entre sistemas en el cerebro murino. Adicionalmente, realizamos estudios de competición de radioligandos del receptor de endocannabinoides CB1 contra ligandos sin marcar del subtipo de receptor de esfingosina-1-fosfato S1P1 (tanto en homogeneizados como en cortes de cerebro). Nuestros resultados concuerdan con aquellos publicados hasta la fecha, y apoyan la hipótesis de una interacción entre los sistemas al menos a nivel de ligando

Neonatal morbidities and developmental delay in moderately preterm-born children

BACKGROUND AND OBJECTIVE: Children born moderately preterm (32-35(6/7) weeks' gestation) are at increased risk of both neonatal morbidities and developmental delays in early childhood. It is unknown whether neonatal morbidities contribute to the increased risk of developmental delay. The objective of this study was to determine the effect of neonatal morbidities after moderately preterm birth on development at preschool age. METHODS: In a community-based, stratified cohort, parents of 832 moderately preterm children born in 2002 or 2003 completed the Ages and Stage Questionnaire when their child was 43 to 49 months old. Data on Apgar scores, asphyxia, tertiary NICU admission, hospital transfer, circulatory insufficiency, hypoglycemia, septicemia, mechanical ventilation, continuous positive airway pressure, apneas, caffeine treatment, and hyperbilirubinemia were obtained from medical records. We assessed associations of neonatal characteristics with developmental delay, adjusted for gender, small-for-gestational-age status, gestational age, and maternal education. RESULTS: Hypoglycemia and asphyxia were associated with developmental delay; odds ratios (ORs) were 2.42 (95% confidence interval [CI]: 1.23-4.77) and 3.18 (95% CI: 1.01-10.0), respectively. Tertiary NICU admission and hyperbilirubinemia had positive but statistically borderline nonsignificant associations with developmental delay: ORs were 1.74 (95% CI: 0.96-3.15) and 1.52 (95% CI: 0.94-2.46), respectively. No other neonatal morbidities were associated with developmental delay. In multivariate analyses, only hypoglycemia was associated with developmental delay (OR: 2.19; 95% CI: 1.08-4.46). CONCLUSIONS: In moderately preterm-born children, only hypoglycemia increased the risk of developmental delay at preschool age. A concerted effort to prevent hypoglycemia might enhance developmental outcome in this group

Quantum information outside quantum information

Premi Extraordinari de Doctorat, promoció 2018-2019. Àmbit de CiènciesQuantum theory, as counter-intuitive as a theory can get, has turned out to make predictions of the physical world that match observations so precisely that it has been described as the most accurate physical theory ever devised. Viewing quantum entanglement, superposition and interference not as undesirable necessities but as interesting resources paved the way to the development of quantum information science. This area studies the processing, transmission and storage of information when one accounts that information is physical and subjected to the laws of nature that govern the systems it is encoded in. The development of the consequences of this idea, along with the great advances experienced in the control of individual quantum systems, has led to what is now known as the second quantum revolution, in which quantum information science has emerged as a fully-grown field. As such, ideas and tools developed within the framework of quantum information theory begin to permeate to other fields of research. This Ph.D. dissertation is devoted to the use of concepts and methods akin to the field of quantum information science in other areas of research. In the same way, it also considers how encoding information in quantum degrees of freedom may allow further development of well-established research fields and industries. This is, this thesis aims to the study of quantum information outside the field of quantum information. Four different areas are visited. A first question posed is that of the role of quantum information in quantum field theory, with a focus in the quantum vacuum. It is known that the quantum vacuum contains entanglement, but it remains unknown whether it can be accessed and exploited in experiments. We give crucial steps in this direction by studying the extraction of vacuum entanglement in realistic models of light-matter interaction, and by giving strict mathematical conditions of general applicability that must be fulfilled for extraction to be possible at all. Another field where quantum information methods can offer great insight is in that of quantum thermodynamics, where the idealizations made in macroscopic thermodynamics break down. Making use of a quintessential framework of quantum information and quantum optics, we study the cyclic operation of a microscopic heat engine composed by a single particle reciprocating between two finite-size baths, focusing on the consequences of the removal of the macroscopic idealizations. One more step down the stairs to applications in society, we analyze the impact that encoding information in quantum systems and processing it in quantum computers may have in the field of machine learning. A great desideratum in this area, largely obstructed by computational power, is that of explainable models which not only make predictions but also provide information about the decision process that triggers them. We develop an algorithm to train neural networks using explainable techniques that exploits entanglement and superposition to execute efficiently in quantum computers, in contrast with classical counterparts. Furthermore, we run it in state-of-the-art quantum computers with the aim of assessing the viability of realistic implementations. Lastly, and encompassing all the above, we explore the notion of causality in quantum mechanics from an information-theoretic point of view. While it is known since the work of John S. Bell in 1964 that, for a same causal pattern, quantum systems can generate correlations between variables that are impossible to obtain employing only classical systems, there is an important lack of tools to study complex causal effects whenever a quantum behavior is expected. We fill this gap by providing general methods for the characterization of the quantum correlations achievable in complex causal patterns. Closing the circle, we make use of these tools to find phenomena of fundamental and experimental relevance back in quantum information.La teoría cuántica, la más extraña y antiintuitiva de las teorías físicas, es también considerada como la teoría más precisa jamás desarrollada. La interpretación del entrelazamiento, la superposición y la interferencia como interesantes recursos aprovechables cimentó el desarrollo de la teoría cuántica de la información (QIT), que estudia el procesado, transmisión y almacenamiento de información teniendo en cuenta que ésta es física, en tanto a que está sujeta a las leyes de la naturaleza que gobiernan los sistemas en que se codifica. El desarrollo de esta idea, en conjunción con los recientes avances en el control de sistemas cuánticos individuales, ha dado lugar a la conocida como segunda revolución cuántica, en la cual la QIT ha emergido como un área de estudio con denominación propia. A consecuencia de su desarrollo actual, ideas y herramientas creadas en su seno comienzan a permear a otros ámbitos de investigación. Esta tesis doctoral está dedicada a la utilización de conceptos y métodos originales del campo de información cuántica en otras áreas. También considera cómo la codificación de información en grados de libertad cuánticos puede afectar el futuro desarrollo de áreas de investigación e industrias bien establecidas. Es decir, esta tesis tiene como objetivo el estudio de la información cuántica fuera de la información cuántica, haciendo hincapié en cuatro ámbitos diferentes. Una primera cuestión propuesta es la del papel de la información cuántica en la teoría cuántica de campos, con especial énfasis en el vacío cuántico. Es conocido que el vacío cuántico contiene entrelazamiento, pero aún se desconoce éste es accesible para su uso en realizaciones experimentales. En esta tesis se dan pasos cruciales en esta dirección mediante el estudio de la extracción de entrelazamiento en modelos realistas de la interacción materia-radiación, y dando condiciones matemáticas estrictas que deben ser satisfechas para que dicha extracción sea posible. Otro campo en el cual métodos propios de QIT pueden ofrecer nuevos puntos de vista es en termodinámica cuántica. A través del uso de un marco de trabajo ampliamente utilizado en información y óptica cuánticas, estudiamos la operación cíclica de un motor térmico microscópico que alterna entre dos baños térmicos de tamaño finito, prestando especial atención a las consecuencias de la eliminación de las idealizaciones macroscópicas utilizadas en termodinámica macroscópica. Acercándonos a aplicaciones industriales, analizamos el potencial impacto de codificar y procesar información en sistemas cuánticos en el ámbito del aprendizaje automático. Un fin codiciado en esta área, inaccesible debido a su coste computacional, es el de modelos explicativos que realicen predicciones, y además ofrezcan información acerca del proceso de decisión que las genera. Presentamos un algoritmo de entrenamiento de redes neuronales con técnicas explicativas que hace uso del entrelazamiento y la superposición para tener una ejecución eficiente en ordenadores cuánticos, en comparación con homólogos clásicos. Además, ejecutamos el algoritmo en ordenadores cuánticos contemporáneos con el objetivo de evaluar la viabilidad de implementaciones realistas. Finalmente, y englobando todo lo anterior, exploramos la noción de causalidad en mecánica cuántica desde el punto de vista de la teoría de la información. A pesar de que es conocido que para un mismo patrón causal existen sistemas cuánticos que dan lugar a correlaciones imposibles de generar por mediación de sistemas clásicos, existe una notable falta de herramientas para estudiar efectos causales cuánticos complejos. Cubrimos esta falta mediante métodos generales para la caracterización de las correlaciones cuánticas que pueden ser generadas en estructuras causales complejas. Cerrando el círculo, usamos estas herramientas para encontrar fenómenos de relevancia fundamental y experimental en la información cuánticaPostprint (published version

Development of moderately preterm-born children

Kinderen die 4 tot 8 weken te vroeg worden geboren, hebben meer kans op ontwikkelingsproblemen dan eerder werd gedacht. Dit blijkt uit de Pinkeltje-studie die UMCG-kinderarts en neonatoloog Jorien Kerstjens heeft opgezet. “Zo’n 7% van alle kinderen in Nederland wordt te vroeg geboren en het overgrote deel daarvan (70-85%) valt in deze groep,” vertelt Kerstjens. “Het is een ‘vergeten’ groep die helemaal geen extra ontwikkelings-follow-up krijgt binnen de kindergeneeskunde, in tegenstelling tot kinderen die meer dan acht weken te vroeg worden geboren, de ‘echte’ prematuren.” Kerstjens pleit voor meer bewustwording van het risico op ontwikkelingsproblemen bij matig te vroeg geborenen omdat juist in deze laatste fase van de zwangerschap nog zo’n 35% van de hersenontwikkeling plaatsvindt. Kerstjens promoveert op 13 mei 2013 aan de Rijksuniversiteit Groningen. Kerstjens vergeleek de ontwikkeling van matig te vroeg geboren kinderen met die van op tijd geboren kinderen en ernstig-vroeggeborenen (minder dan 32 weken zwangerschap). Op vierjarige leeftijd vond zij bij 8,3% van de matig te vroeg geboren kinderen ontwikkelingsproblemen, twee keer zoveel als bij op-tijd geboren kinderen. Bij ernstig-vroeggeborenen kwam dit voor bij 14,9% van de kinderen. Op zevenjarige leeftijd scoorden de matig te vroeg geboren kinderen in vergelijking met op-tijd geborenen minder goed qua IQ, ontwikkeling van visueel-ruimtelijke vaardigheden zoals puzzels leggen, aandacht, en selectief kunnen focussen op wat belangrijk is. “Lang werd gedacht dat het altijd wel goed zou komen met de ontwikkeling van matig te vroeg geboren kinderen, maar mijn onderzoek laat zien dat er bij een deel van deze kinderen wel degelijk sprake is van een langdurige ontwikkelingsachterstand”, aldus Kerstjens.Children born 4-8 weeks prematurely have a higher risk of developmental problems than previously presumed. This is one of the findings in the Pinkeltje study, set up by UMCG paediatrician and neonatologist Jorien Kerstjens. ‘Some seven percent of all children in the Netherlands are born prematurely and the majority of them (70-85%) fall into this category,’ says Kerstjens. ‘It is a “forgotten” group. Unlike children born more than eight weeks prematurely (the “real” premature infants), paediatrics does not provide follow-up monitoring during their development.’ In view of the fact that 35% of brain development takes place in the final phase of pregnancy, Kerstjens is arguing for greater awareness of the risk of developmental problems in moderately preterm-born children. She will be awarded a PhD by the University of Groningen on 13 May 2013. Kerstjens compared the development of children born moderately prematurely with that of children born full term and very prematurely (pregnancy of less than 32 weeks). At four years of age, she found developmental problems in 8.3% of the moderately preterm-born children, which is double the percentage found in children born full term. Developmental problems were evident in 14.9% of the seriously preterm-born children. By the age of seven, the moderately preterm-born children were scoring lower than children born full term for IQ, the development of visual-spatial skills (such as doing jigsaws), attention span and selective focusing on main issues. ‘Up until now, it was generally assumed that moderately preterm-born children would develop normally, but my research shows that some of these children show clear signs of long-term developmental problems’, says Kerstjens. Exponential The more prematurely infants are born, the higher the risk of developmental problems, concludes Kerstjens. ‘We think this is because the most important part of brain development takes place in the third trimester of pregnancy. Many premature infants have also experienced other problems relating to the placenta; they are put into incubators immediately after birth, are fed differently and exposed to different stimuli than if they had been carried to full term. This causes their brains to develop differently from children born full term.’ Kerstjens would like to see more attention paid to these risks when deciding whether or not to deliver an infant before term. Factors A number of well-known factors increase the risks of premature labour and developmental problems in moderately preterm-born children. Kerstjens cites smoking during pregnancy and obesity on the part of the mother. ‘Multiple pregnancies also tend to be shorter. Fertility treatment such as IVF often leads to multiple births. Indirectly, my research seems to be advising women not to wait too long before getting pregnant,’ says Kerstjens. Social importance According to Kerstjens, we are currently putting a lot of effort into monitoring and helping children born more than eight weeks prematurely. ‘This is obviously important, but we should be doing more for the group of moderately preterm-born children too. The social importance of monitoring and helping this group should not be underestimated. It’s actually more important than helping the group of very preterm-born children.’ In absolute terms, the group of moderately preterm-born 4-year-olds with retarded development in the Netherlands is probably twice as large as the group of more seriously preterm-born 4-year-olds with developmental problems. Kerstjens thinks that helping these children during the first four years of their lives may improve their opportunities in the future. She is also predicting more attention world-wide for moderately preterm-born children