Caracterización energética y ambiental de materiales de almacenamiento de calor latente

El uso de materiales de cambio de fase representa una de las alternativas más prometedoras en cuanto a sistemas pasivos utilizados en edificación. No obstante, la correcta selección de estos materiales es fundamental, ya que su funcionamiento depende de varios aspectos como la climatología, la ubicación, el tipo de material seleccionado y sus características termofísicas. Por tanto, el objetivo de este trabajo es realizar la caracterización energética y ambiental de la aplicación de estos materiales en edificación. Por un lado, mediante simulación se determina la demanda energética de climatización existente en un edificio modelo, con y sin la aplicación de estos materiales, y posteriormente, se realiza la caracterización ambiental considerando el enfoque del Análisis de Ciclo de Vida, obteniendo resultados para diferentes escenarios de aplicación sobre una base cerámica donde se ha estudiado el efecto de diversas variables como las Severidades Climáticas existentes en España o la naturaleza de los materiales de cambio de fase. Esta investigación evidencia como la utilización de una solución constructiva formada por una baldosa cerámica y una capa de materiales de cambio de fase seleccionados adecuadamente, no solo aporta descensos en la demanda energética en todas las condiciones climáticas, siendo en algunas de ellas superiores al 15%, sino que también se obtienen beneficios ambientales en cortos espacios temporales en comparación con la vida útil de la solución constructiva.Consejo General de la Arquitectura Técnica de Españ

Role of the cellular prion protein in oligodendrocyte precursor cell proliferation and differentiation in the developing and adult mouse CNS

There are numerous studies describing the signaling mechanisms that mediate oligodendrocyte precursor cell (OPC) proliferation and differentiation, although the contribution of the cellular prion protein (PrPc) to this process remains unclear. PrPc is a glycosyl-phosphatidylinositol (GPI)-anchored glycoprotein involved in diverse cellular processes during the development and maturation of the mammalian central nervous system (CNS). Here we describe how PrPc influences oligodendrocyte proliferation in the developing and adult CNS. OPCs that lack PrPc proliferate more vigorously at the expense of a delay in differentiation, which correlates with changes in the expression of oligodendrocyte lineage markers. In addition, numerous NG2-positive cells were observed in cortical regions of adult PrPc knockout mice, although no significant changes in myelination can be seen, probably due to the death of surplus cells

Functional Heterogeneity of Mouse and Human Brain OPCs: Relevance for Preclinical Studies in Multiple Sclerosis.

Besides giving rise to oligodendrocytes (the only myelin-forming cell in the Central Nervous System (CNS) in physiological conditions), Oligodendrocyte Precursor Cells (OPCs) are responsible for spontaneous remyelination after a demyelinating lesion. They are present along the mouse and human CNS, both during development and in adulthood, yet how OPC physiological behavior is modified throughout life is not fully understood. The activity of adult human OPCs is still particularly unexplored. Significantly, most of the molecules involved in OPC-mediated remyelination are also involved in their development, a phenomenon that may be clinically relevant. In the present article, we have compared the intrinsic properties of OPCs isolated from the cerebral cortex of neonatal, postnatal and adult mice, as well as those recovered from neurosurgical adult human cerebral cortex tissue. By analyzing intact OPCs for the first time with 1H High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (1H HR-MAS NMR) spectroscopy, we show that these cells behave distinctly and that they have different metabolic patterns in function for their stage of maturity. Moreover, their response to Fibroblast Growth Gactor-2 (FGF-2) and anosmin-1 (two molecules that have known effects on OPC biology during development and that are overexpressed in individuals with Multiple Sclerosis (MS)) differs in relation to their developmental stage and in the function of the species. Our data reveal that the behavior of adult human and mouse OPCs differs in a very dynamic way that should be very relevant when testing drugs and for the proper design of effective pharmacological and/or cell therapies for MS.post-print753 K

Contribution to the development of product category rules for ceramic bricks

An Environmental Product Declaration (EPD) provides information on a product's environmental performance along its life cycle. This paper aims to contribute to the development of Product Category Rules (PCR) specific for ceramic bricks in order to support the establishment of a “cradle to grave” EPD. The methodology for developing the PCR takes into account ISO 14025, ISO 21930 and EN 15804, and the environmental profile is based on the Life Cycle Assessment (LCA) methodology. In this context, some core issues like product category definition, impact categories, indicators, cut-off criteria and allocation criteria are addressed. The selected impact categories for this study were: global warming, ozone layer depletion, photochemical oxidation, acidification, eutrophication, depletion of abiotic resources and respiratory inorganics. Indicators of energy and water consumption were also considered, as well as particle emissions to air. The results obtained from an LCA study on ceramic bricks produced in Portugal, to support the development of the PCR, show that the use of different fuels in the brick manufacturing stage has a significant effect in some impact categories. The use of petroleum coke generates higher impacts than natural gas or biomass. In general, the major environmental impacts occur in the brick manufacturing stage, mainly due to fuel usage in the firing operation. Particle emissions to air should be considered as an additional parameter in the EPD, being especially important when solid fuels are used. A sensitivity analysis of the cut-off criteria options was also conducted, which concluded that a 0.5% decrease in mass proved to be adequate for adoption, with a significant reduction in the effort required for data collection

Role of the Cellular Prion Protein in Oligodendrocyte Precursor Cell Proliferation and Differentiation in the Developing and Adult Mouse CNS

There are numerous studies describing the signaling mechanisms that mediate oligodendrocyte precursor cell (OPC) proliferation and differentiation, although the contribution of the cellular prion protein (PrPc) to this process remains unclear. PrPc is a glycosyl-phosphatidylinositol (GPI)-anchored glycoprotein involved in diverse cellular processes during the development and maturation of the mammalian central nervous system (CNS). Here we describe how PrPc influences oligodendrocyte proliferation in the developing and adult CNS. OPCs that lack PrPc proliferate more vigorously at the expense of a delay in differentiation, which correlates with changes in the expression of oligodendrocyte lineage markers. In addition, numerous NG2-positive cells were observed in cortical regions of adult PrPc knockout mice, although no significant changes in myelination can be seen, probably due to the death of surplus cells

Cell Fate Potential of NG2 Progenitors

Determining the origin of different glial subtypes is crucial to understand glial heterogeneity, and to enhance our knowledge of glial and progenitor cell behavior in embryos and adults. NG2-glia are homogenously distributed in a grid-like manner in both, gray and white matter of the adult brain. While some NG2-glia in the CNS are responsible for the generation of mature oligodendrocytes (OPCs), most of them do not differentiate and they can proliferate outside of adult neurogenic niches. Thus, NG2-glia constitute a heterogeneous population containing different subpopulations with distinct functions. We hypothesized that their diversity emerges from specific progenitors during development, as occurs with other glial cell subtypes. To specifically target NG2-pallial progenitors and to define the NG2-glia lineage, as well as the NG2-progenitor potential, we designed two new StarTrack strategies using the NG2 promoter. These approaches label NG2 expressing progenitor cells, permitting the cell fates of these NG2 progenitors to be tracked in vivo. StarTrack labelled cells producing different neural phenotypes in different regions depending on the age targeted, and the strategy selected. This specific genetic targeting of neural progenitors in vivo has provided new data on the heterogeneous pool of NG2 progenitors at both embryonic and postnatal ages.This work was supported by research Grants from the Ministerio de Economía y Competitividad (MINECO; BFU2016-75207-R) and Fundación Ramón Areces (Ref. CIVP9A5928)

A Clonal NG2-Glia Cell Response in a Mouse Model of Multiple Sclerosis

© 2020 by the authors.NG2-glia, also known as oligodendrocyte precursor cells (OPCs), have the potential to generate new mature oligodendrocytes and thus, to contribute to tissue repair in demyelinating diseases like multiple sclerosis (MS). Once activated in response to brain damage, NG2-glial cells proliferate, and they acquire a reactive phenotype and a heterogeneous appearance. Here, we set out to investigate the distribution and phenotypic diversity of NG2-glia relative to their ontogenic origin, and whether there is a clonal NG2-glial response to lesion in an experimental autoimmune encephalomyelitis (EAE) murine model of MS. As such, we performed in utero electroporation of the genomic lineage tracer, StarTrack, to follow the fate of NG2-glia derived from single progenitors and to evaluate their response to brain damage after EAE induction. We then analyzed the dispersion of the NG2-glia derived clonally from single pallial progenitors in the brain of EAE mice. In addition, we examined several morphological parameters to assess the degree of NG2-glia reactivity in clonally-related cells. Our results reveal the heterogeneity of these progenitors and their cell progeny in a scenario of autoimmune demyelination, revealing the ontogenic phenomena at play in these processes.This research was funded by research Grants from the Fundación Ramón Areces (Ref. CIVP9A5928), MINECO (BFU2016-75207-R), SAF2016-75292-R, CIBERNED and Gobierno Vasco (IT1203-19).Peer reviewe

Efecto mitógeno de Sonic hedgehog (Shh) sobre precursores de oligodendrocitos y su uso en enfermedades desmielinizantes

Efecto mitógeno de Sonic hedgehog (Shh) sobre precursores de oligodendrocitos y su uso en enfermedades desmielinizantes. La presente invención se refiere al efecto mitogénico de la proteína Sonic hedgehog (Shh) sobre células precursoras de oligodendrocitos. En concreto, y debido a dicho efecto mitogénico, la presente invención comprende el uso de Shh para la expansión de células precursoras de oligodendrocitos in vitro, así como su aplicación en la elaboración de composiciones farmacéuticas para el tratamiento de enfermedades desmielinizantes.Peer reviewedUniversidad de Salamanca, Consejo Superior de Investigaciones Científicas (España)B1 Patente con informe sobre el estado de la ténic

Decoding the progeny of NG2 and GFAP progenitor cells.

During cortical development, cell generation follow a sequential pattern in partially overlapping temporal waves. Firstly, neural progenitor cells (NPCs) derived from neuroepithelial cells divide symmetrically to expand their population pool, before their gradual transition into radial glia (RG) cells. RG cells initially undergo symmetric cell divisions and later asymmetric RG division produce neurons first, then astrocytes and at later stages oligodendrocytes. Recent studies support the notion that RG cells might be heterogeneous regarding their differentiation and fate potential. Another remarkable cell type, which could act as precursor cells, are NG2-cells. In vivo cell fate analyses indicate that NG2-cells are oligodendrocyte precursor cells (OPCs) but fate-mapping analysis, in different transgenic mice lines, also revealed different degrees of differentiation and maturation properties of NG2 cells depending on brain areas. In addition, some studies suggest that in response to brain injury reactive astrocytes arise from endogenous progenitors located in the adult brain parenchyma like NG2 cells. Thus, such diversity implies that those cells conform a heterogeneous population composed by different subpopulations devoted to distinct functions. Then, most NG2-cells lineage is unknown and has not been explored to decode whether the NG2-cells is a homogeneous cell population that displays different properties depending on environmental influences or is an intrinsically heterogeneous cell. In order to decipher the cell progeny of early neural progenitors expressing either GFAP or NG2, we targeted SVZ progenitors. To this end, we exchanged the CMV promoter in the piggyback transposase by the GFAP (GFAP-hyPBase) or the NG2 (NG2-hyPBase) promoters to produce specific labeling of progenitor cells that are expressing GFAP or NG2 genes at the time of electroporation. These new transposases also recognize the terminal repeats of UbC-StarTrack plasmids to guarantee the permanent labeling of neural cells. Then, after in vivo electroporation of the Ubc-StarTrack mixture along with the different transposase, we analyzed their cell progeny in adult brain mouse allowing to distinguish different cell subpopulations between GFAP progenitors or NG2 progenitors. Our findings provide fundamental aspects of the lineage heterogeneity and cell fate determination of different and specific progenitor cellsSupported by research Grant BFU2016-75207-R from MINECO

Decoding astrocyte heterogeneity: New tools for clonal analysis.

The importance of astrocyte heterogeneity came out as a hot topic in neurosciences especially over the last decades, when the development of new methodologies allowed demonstrating the existence of big differences in morphological, neurochemical and physiological features between astrocytes. However, although the knowledge about the biology of astrocytes is increasing rapidly, an important characteristic that remained unexplored, until the last years, has been the relationship between astrocyte lineages and cell heterogeneity. To fill this gap, a new method called StarTrack was recently developed, a powerful genetic tool that allows tracking astrocyte lineages forming cell clones. Using StarTrack, a single astrocyte progenitor and its progeny can be specifically labeled from its generation, during embryonic development, to its final fate in the adult brain. Because of this specific labeling, astrocyte clones, exhibiting heterogeneous morphologies and features, can be easily analyzed in relation to their ontogenetic origin. This review summarizes how astrocyte heterogeneity can be decoded studying the embryonic development of astrocyte lineages and their clonal relationship. Finally, we discuss about some of the challenges and opportunities emerging in this exciting area of investigation.This work was supported by research Grant BFU2013-48807-R from the Spanish Ministry of Economy and Competitiveness