MicroRNAs-Proteomic Networks Characterizing Human Medulloblastoma-SLCs

Medulloblastoma (MB) is the most common malignant brain tumor of pediatric age and is characterized by cells expressing stem, astroglial, and neuronal markers. Among them, stem-like cells (hMB-SLCs) represent a fraction of the tumor cell population with the potential of self-renewal and proliferation and have been associated with tumor poor prognosis. In this context, microRNAs have been described as playing a pivotal role in stem cells differentiation. In our paper, we analyze microRNAs profile and genes expression of hMB-SLCs before and after Retinoic Acid- (RA-) induced differentiation. We aimed to identify pivotal players of specific pathways sustaining stemness and/or tumor development and progression and integrate the results of our recent proteomic study. Our results uncovered 22 differentially expressed microRNAs that were used as input together with deregulated genes and proteins in the Genomatix Pathway System (GePS) analysis revealing 3 subnetworks that could be interestingly involved in the maintenance of hMB-SLCs proliferation. Taken together, our findings highlight microRNAs, genes, and proteins that are significantly modulated in hMB-SLCs with respect to their RA-differentiated counterparts and could open new perspectives for prognostic and therapeutic intervention on MB

Petrogénesis del cuerpo de cromitita de la ofiolita del Cerro Colorado, península de Paraguaná, Venezuela

This research was financially supported by FEDER Funds through the projects CGL2015-65824-P and CGL2014-55949-R granted by the Spanish "Ministerio de Economia y Competitividad." Additional funding was provided by the Ramon y Cajal Fellowship RYC-2015-17596 granted by the Spanish MINECO to JMGJ.Ultramafic-mafic rocks of ophiolitic affinity crop out along the Venezuelan Caribbean region. They have been interpreted as remnants of the oceanic lithosphere of the Caribbean volcanic arc (135-70 Ma) as well as relicts of proto-Caribbean oceanic lithosphere (Upper Jurassic-Lower Cretaceous) related to Pangea’s break-up. The Cerro Colorado ophiolite, located in the Paraguaná Peninsula, together with the case of the Cordillera de la Costa in north-central Venezuela, are a unique case of these Venezuelan ophiolites containing chromitite bodies. However, the petrogenesis of such a mafic-ultramafic complex and associated chromite ore remains are unknown to date. To advance our understanding of chromite ores in the Caribbean region, the genesis of the Cerro Colorado chromitite body is challenged. The Cerro Colorado chromitite body is characterized by a low-Cr content [Cr# =Cr/ Cr+Al= 0.44-0.60] and a distribution of trace elements in chromite as is typical of high-Al chromitites found in the shallower portions of the petrological Moho Transition Zone of Mesozoic ophiolites. The calculated melts in equilibrium with chromite forming this high-Al chromitite body are back-arc basin basalts. These melts were extracted after ~20 % partial melting of moderately depleted peridotites, which resulted in the precipitation of high-Al chromitite relatively impoverished in PGE (≤ 100 ppb total PGE). A comparison of the geochemical signatures of minor and trace elements in chromite and bulk-PGE contents of the Cerro Colorado chromitite with those of other known chromitites in the peri-Caribbean ophiolites show certain similitude with those high-Al described in the Moa-Baracoa ophiolite in eastern Cuba. The obtained results allow us to suggest that the ultramafic rocks of the Cerro Colorado and the chromitite body associated with it are closely related to the formation of a back-arc basin developed between ca. 125-120 Ma in the rear of the Great Antilles Arc.El margen caribeño de Venezuela se caracteriza por la presencia de algunos afloramientos de rocas máficas y ultramáficas de afinidad ofiolíca. Dichas rocas se han intepretado como fragmentos de la litosfera oceánica del Arco volcánico Caribeano (~135-70 Ma) así como relictos de la litosfera oceánica del proto-Caribe (Jurásico Superior-Cretácico Inferior) relacionados con la ruptura de Pangea. La ofiolita de Cerro Colorado, localizada en la Península de Paraguaná es, conjuntamente con el caso de la Cordillera de la Costa en la parte centro norte de Venezuela, el único caso de esas ofiolitas Venezolanas que contienen cuerpos de cromititas. Sin embargo, se desconoce aún la petrogénesis de dichos complejos de rocas máficas y ultramáficas. Con el objeto de avanzar en el estado del conocimiento de la génesis de menas de cromita en la región del Caribe, en este trabajo se aborda el estudio de la génesis del cuerpo de cromitita de Cerro Colorado. El cuerpo de cromitita de Cerro Colorado está constituido esencialmente por cromita con bajo contenido en Cr [Cr# =Cr/ Cr+Al= 0.44-0.60] y una distribución de elementos trazas similar a la descrita en otras cromititas con alto contenido en Al documentadas en las zonas más someras de la Zona de Transición de la Moho petrológica de otras ofiolitas de edad Mesozoica. Los fundidos calculados en equilibrio con la cromita que forma este cuerpo de cromititas con alto Al son basaltos de trasera de arco. Estos fundidos fueron extraídos de una mantélica formada por peridotitas empobrecidas como resultado de tasas de fusión parcial de ~20 %, lo que dió lugar a la precipitación de cromititas con alto Al relativamente empobrecidas en EGP (≤ 100 ppb suma total de EGP). Una comparación de las firmas geoquímicas de los elementos menores y trazas en la cromita y contenidos de EGP obtenidos a partir del análisis de muestras de roca total de la cromitita de Cerro Colorado con otras cromititas documentadas en el manto de ofiolitas peri-Caribeñas muestra cierta similitud con aquellas altas en Al descritas en la ofiolita de Moa-Baracoa en Cuba oriental. Los resultados obtenidos nos permiten sugerir que las rocas ultramáficas de Cerro Colorado y el cuerpo de cromitita que éstas albergan están íntimamente relacionados con la formación de una cuenca de retro arco desarrollada en un el intervalo temporal 125-120 Ma en la trasera del Arco de las Antillas Mayores.FEDER Funds - Spanish "Ministerio de Economia y Competitividad CGL2015-65824-P CGL2014-55949-RRamon y Cajal Fellowship - Spanish MINECO RYC-2015-1759

Morfologías del olvido: Ocupación histórica del espacio y vulnerabilidad en el Litoral Central de Venezuela

El Litoral Central de Venezuela es una región constreñida por sus condiciones naturales y con apenas un breve espacio para el desarrollo urbano, el cual fue impulsado recién desde la década de 1950. A partir de entonces la región ofrece un aspecto unificado por vías y avenidas interconec-tadas de Este a Oeste, en contraposición a su condición histórica de región inconexa y con asen-tamientos aislados entre sí. La ocupación de este espacio desde el siglo XVI en adelante ha estado signada por los intereses de Caracas con diferentes fases, según los contextos históricos, y en nin-gún caso su desarrollo ha estado articulado con el ambiente donde se asientan sus poblaciones. El resultado de este proceso, especialmente desde su urbanización moderna hasta el presente, ha sido el enterramiento de la memoria local y regional, incluso físicamente, sepultando la morfolo-gía característica en beneficio de una cultura de balneario, y fundando una sociedad de espaldas a su hábitat natural y en profundas condiciones de vulnerabilidad. Este trabajo analiza este proble-ma sobre la base de la reconstrucción histórica de ese proceso, y el estudio directo y en campo de las características morfológicas que conforman a la región

Vestiges of the proto-Caribbean seaway: origin of the San Souci Volcanic Group, Trinidad

Outcrops of volcanic–hypabyssal rocks in Trinidad document the opening of the proto-Caribbean seaway during Jurassic–Cretaceous break-up of the Americas. The San Souci Group on the northern coast of Trinidad comprises the San Souci Volcanic Formation (SSVF) and passive margin sediments of the ~ 130–125 Ma Toco Formation. The Group was trapped at the leading edge of the Pacific-derived Caribbean Plate during the Cretaceous–Palaeogene, colliding with the para-autochthonous margin of Trinidad during the Oligocene–Miocene. In-situ U–Pb ion probe dating of micro-zircons from a mafic volcanic breccia reveal the SSVF crystallised at 135.0 ± 7.3 Ma. The age of the SSVF is within error of the age of the Toco Formation. Assuming a conformable contact, geodynamic models indicate a likely origin for the SSVF on the passive margin close to the northern tip of South America. Immobile element and Nd–Hf radiogenic isotope signatures of the mafic rocks indicate the SSVF was formed by ≪10% partial melting of a heterogeneous spinel peridotite source with no subduction or continental lithospheric mantle component. Felsic breccias within the SSVF are more enriched in incompatible elements, with isotope signatures that are less radiogenic than the mafic rocks of the SSVF. The felsic rocks may be derived from re-melting of mafic crust. Although geochemical comparisons are drawn here with proto-Caribbean igneous outcrops in Venezuela and elsewhere in the Caribbean more work is needed to elucidate the development of the proto-Caribbean seaway and its rifted margins. In particular, ion probe dating of micro-zircons may yield valuable insights into magmatism and metamorphism in the Caribbean, and in altered basaltic terranes more generally

GEOLOGIA DE LAS MARGENES DE LA PLACA DEL CARIBE: GENERALIDADES EN GUATEMALA, COSTA RICA, LA ESPAÑOLA Y RESULTADOS PRELIMINARES DEL ANALISIS DE UNA TRANSVERSAL EN LA CORDILLERA DE LA COSTA DE VENEZUELA

The Caribbean Plate margins are constituted by deformed belts built up since the Cretaceous in acompressional and strike-slip stress field, which allowed overthrusting of the Caribbean crust onto the Pacific,North and South American Plates.The Caribbean borders include Jurassic-Cretaceous ophiolitic units (Great Antilles, Venezuela, Costa Rica,Guatemala, etc.), composed by mantle peridotites, gabbros, volcanic and sedimentary covers, which have beendeformed in at least two ductile penetrative phases and were often metamorphosed in the prehnite-pumpelleyite,green and blue schist, amphibolite, and in places eclogite facies. These units may present part of a subductioncomplex or are an accretionary prism.This paper deals with a regional geological survey (1989-1993) conducted on the main periCaribbean ophioliticunits of Guatemala, Costa Rica, Hispanola, and Venezuela. The preliminary data, recently updated with new anddetailed researches, allow to recognize the magmatic affinities (MORB and IAT) of the different reconstructedlithological sequences, which can be related with an hypothetical kinematic model of the development of theCaribbean Plate. Los márgenes de la placa del Caribe están constituidos por cinturones deformados debido a una seriede fases compresivas ocurridas desde el Cretácico, con esfuerzos tensionales y/o fallas transcurrentes super-puestos. Estos cinturones deformados contienen porciones variables de corteza caribeña sobrecorrida a las placasadyacentes (Norte y Suramericana, Pacífica).En las Antillas Mayores, Venezuela, Costa Rica y Guatemala se conocen unidades ofiolíticas de edad Jurásica-Cretácica, constituidas por secuencias de manto, corteza y una cubierta sedimentaria más o menos espesa; lassecuencias se encuentran generalmente serpentinizadas, deformadas en al menos dos fases dúctiles penetrativas ymetamorfizadas en las facies prehnita-pumpellita, esquistos azules y esquistos verdes.Desde el punto de vista tectónico-cinemático es posible incluir estas unidades en porciones de complejos de sub-ducción construidos por accreción o "underplating".En el presente estudio regional sobre las principales unidades ofiolíticas de los márgenes del Caribe, se eviden cian diferentes secuencias litológicas pertenecientes a procesos evolutivos con diferentes tendencias, desde MORB a IAT.Los resultados preliminares de una transversal en la Cordillera de la Costa de Venezuela permiten interpretar algunas secuencias litológicas como provenientes de protolitos tipo MOR

Giovanni Sartori e la democrazia della Seconda Repubblica

Il saggio ripercorre e analizza criticamente tutti i passaggi istituzionali della cosiddetta Seconda Repubblica, ossia della peculiare democrazia maggioritaria che si imposta in Italia a partire dal 1994. Tali passaggi sono visti all'interno del pensiero di Giovanni Sartori e in particolare della sua teoria della democrazia. Tale pensiero si è manifestato sia attraverso opere scientifiche sia attraverso una continua attività pubblicistica, in particolare dalle colonne, come editorialista, del Corriere della Sera. Dall'esame di questo pensiero emerge una serrata e continua critica dei caratteri istituzionali della peculiare democrazia maggioritaria all'italiana.The essay traces and critically analyzes all the institutional steps of the so-called Italian Second Republic, that is the peculiar majoritarian democracy that is set in Italy since 1994. These steps are seen within the thoughts of Giovanni Sartori and in particular of his theory of democracy . Such thinking has manifested both through scientific works both through continuous publications, in particular from the columns, as a columnist, of the Corriere della Sera. From an examination of this thinking emerges a close and continuous criticism of the institutional character of the distinctive Italian style majoritarian democracy

Prvi koraki k razumevanju notranje ranljivosti kraških vodonosnikov za onesnaženje v južnoameriških in karibskih državah

Protecting groundwater in karst aquifers is extremely impor­tant. Vulnerability maps can greatly help proper decision mak­ing based on physical environmental attributes that influence how easily a contaminant applied to the land surface can reach groundwater due to anthropogenic activities, and the proper­ties of the contaminants. Methods for determining vulnerabil­ity based on the COST Action 620 Approach, when applied in the study area, may lead to contradictory results. The main purpose of this study is to provide an overview of academic research on intrinsic karst aquifer vulnerability methodologies applied in South American and Caribbean countries. Secondly, it describes studies related to karst aquifers that, in some cases, lack specific information on intrinsic vulnerability. The objec­tive is to encourage and to help develop specific methods for determining karst vulnerability in these regions. To achieve these purposes, a systematic literature review was conducted including studies conducted at institutions such as universities, national water institutes, and by geological services. Several methods have been used in the region such as COP, DRAS­TIC, RISK, EPIK, PI, PaPRIka, and the Slovene Approach. And some attempts have been made to develop a specific methodol­ogy that best suits the specificities of the region’s karst aqui­fers. South America and the Caribbean have almost 5 % of the world´s carbonate rocks. Some countries have large extensions of their territory covered by karst rocks, such as Peru, 15.4 %; Cuba, 67 %; and Mexico 25.29 %. Estimates indicate that more than 10 million people use water from karst systems in Mexico. In Cuba, 33 % of all available water volume originates from groundwater, and 91.51 % from karst aquifers. In Mexico, 13 studies have been conducted on the importance of karst aqui­fers, which mostly address the Yucatan Peninsula, followed by Brazil (9 studies), Cuba (5), Colombia (1) and Peru (1). Infor­mation about the theme is scarce in most of the other countries in the region. Some studies have incongruent results given the regional characteristics of tropical karst.Varovanje podzemne vode na kraških vodonosnikih je izjemno pomembno. V veliko pomoč pri pravilnem odločanju na pod­lagi dejanskih okoljskih značilnosti, ki vplivajo na to, kako zlahka lahko onesnaževalo, uporabljeno na površini tal, zaradi antropo­genih dejavnosti in lastnosti onesnaževal doseže podzemno vodo, so lahko karte ranljivosti. Z metodami za opredelitev ranljivosti, ki temeljijo na pristopu COST Action 620, se lahko pri uporabi na proučevanem območju pridobijo nasprotujoči si rezultati. Glavni cilj te študije je zagotoviti pregled akademskih raziskav o metodologijah za ugotavljanje notranje ranljivosti kraških vodonosnikov, ki se uporabljajo v južnoameriških in karibskih državah. Poleg tega je podan opis študij, povezanih s kraškimi vodonosniki, pri čemer v nekaterih primerih ni specifičnih in­formacij o notranji ranljivosti. Cilj je spodbuditi in pomagati pri razvoju specifičnih metod za opredelitev kraške ranljivosti v teh regijah. Za dosego teh ciljev je bil opravljen sistematičen pregled literature, ki je vključeval študije, izvedene v institucijah, kot so univerze, nacionalni inštituti za vode in geološke službe. V regi­jah je bilo uporabljenih več metod, kot so COP, DRASTIC, RISK, EPIK, PI, PaPRIka in slovenski pristop. Poleg teh je bilo nekaj poskusov za pripravo specifične metodologije, ki bi najbolje us­trezala posebnostim kraških vodonosnikov v regijah. V Južni Ameriki in na Karibih je skoraj 5 % vseh karbonatnih kamnin na svetu. V nekaterih državah so veliki predeli prekriti s kraškimi kamninami, na primer v Peruju 15,4 %, na Kubi 67 % in v Mehiki 25,29 %. Po ocenah več kot 10 milijonov ljudi v Mehiki uporablja vodo iz kraških sistemov. Na Kubi 33 % vse razpoložljive količine vode izvira iz podzemne vode, 91,51 % pa s kraških vodonos­nikov. V Mehiki je bilo opravljenih 13 študij o pomenu kraških vodonosnikov, s katerimi so obravnavali večinoma polotok Ju­katan ter Brazilijo (9 študij), Kubo (5), Kolumbijo (1) in Peru (1). V večini drugih držav v regijah je informacij o tej temi malo. V nekaterih študijah so glede na regionalne značilnosti tropskega krasa rezultati neusklajeni

Mesenchymal Stem Cell-Based Immunomodulation in Allogeneic Heterotopic Heart-Lung Transplantation

Mesenchymal stem cells are able to differentiate in various cell lineages and they have shown immunomodulatory properties in vitro, altering the cytokine secretion profile of T helper, T effector and dendritic cells and stimulating natural killer cells towards an anti-inflammatory and tolerant phenotype. In vivo they prolong skin allograft survival and may decrease graft-versus-host disease after hematopoietic stem cell transplants. In this work we studied the effects of mesenchymal stem cell treatment in an allogeneic heterotopic heart-lung transplant model. The following experimental groups were formed: A) Control B) Immunosuppressive therapy (Cyclosporine A) C) Mesenchymal stem-cell intravenous infusion D) Mesenchymal stem-cell infusion plus immunosuppressive treatment. The infusion of mesenchymal stem cells improved the mean graft survival up to 14.5±3.7 days with respect to the control group (3±0.6 days). Treatment with Cyclosporine A plus mesenchymal stem cells (group D) produced a mean survival time of 18.25±4.9 days, and was not significantly different to the results for group B (21.75±3.5 days). Furthermore, in the immunosuppressive treatment and the mesenchymal stem cell treatment, histological analysis revealed a reduction in the grade of rejection in heart and lung grafts. This decrease was most significant in group D. In conclusion, mesenchymal stem cells alone or in combination with Cyclosporine A were able to prolong graft survival time. These data suggest that, in vivo, mesenchymal stem cells retain their ability, already shown in vitro, to suppress lymphocyte activation and proliferation

First Steps to understanding Intrinsic Vulnerability to Contamination of Karst Aquifers in Various South American and Caribbean Countries

Protecting groundwater in karst aquifers is extremely impor­tant. Vulnerability maps can greatly help proper decision mak­ing based on physical environmental attributes that influence how easily a contaminant applied to the land surface can reach groundwater due to anthropogenic activities, and the proper­ties of the contaminants. Methods for determining vulnerabil­ity based on the COST Action 620 Approach, when applied in the study area, may lead to contradictory results. The main purpose of this study is to provide an overview of academic research on intrinsic karst aquifer vulnerability methodologies applied in South American and Caribbean countries. Secondly, it describes studies related to karst aquifers that, in some cases, lack specific information on intrinsic vulnerability. The objec­tive is to encourage and to help develop specific methods for determining karst vulnerability in these regions. To achieve these purposes, a systematic literature review was conducted including studies conducted at institutions such as universities, national water institutes, and by geological services. Several methods have been used in the region such as COP, DRAS­TIC, RISK, EPIK, PI, PaPRIka, and the Slovene Approach. And some attempts have been made to develop a specific methodol­ogy that best suits the specificities of the region’s karst aqui­fers. South America and the Caribbean have almost 5 % of the world´s carbonate rocks. Some countries have large extensions of their territory covered by karst rocks, such as Peru, 15.4 %; Cuba, 67 %; and Mexico 25.29 %. Estimates indicate that more than 10 million people use water from karst systems in Mexico. In Cuba, 33 % of all available water volume originates from groundwater, and 91.51 % from karst aquifers. In Mexico, 13 studies have been conducted on the importance of karst aqui­fers, which mostly address the Yucatan Peninsula, followed by Brazil (9 studies), Cuba (5), Colombia (1) and Peru (1). Infor­mation about the theme is scarce in most of the other countries in the region. Some studies have incongruent results given the regional characteristics of tropical karst