124 research outputs found
Cabut, a C<sub>2</sub>H<sub>2</sub> zinc finger transcription factor, is required during <em>Drosophila</em> dorsal closure downstream of JNK signaling
AbstractDuring dorsal closure, the lateral epithelia on each side of the embryo migrate dorsally over the amnioserosa and fuse at the dorsal midline. Detailed genetic studies have revealed that many molecules are involved in this epithelial sheet movement, either with a signaling function or as structural or motor components of the process. Here, we report the characterization of cabut (cbt), a new Drosophila gene involved in dorsal closure. cbt is expressed in the yolk sac nuclei and in the lateral epidermis. The Cbt protein contains three C2H2-type zinc fingers and a serine-rich domain, suggesting that it functions as a transcription factor. cbt mutants die as embryos with dorsal closure defects. Such embryos show defects in the elongation of the dorsal-most epidermal cells as well as in the actomyosin cable assembly at the leading edge. A combination of molecular and genetic analyses demonstrates that cbt expression is dependent on the JNK cascade during dorsal closure, and it functions downstream of Jun regulating dpp expression in the leading edge cells
Valoración funcional en pacientes intervenidos medianteplastia de LCA con semitendinoso-recto interno y sistema Togglelock.
Introducción: Una de las lesiones más frecuente de la rodilla y que está en aumento, sobre todo en el ámbito deportivo es la lesión del ligamento cruzado anterior. La reconstrucción quirúrgica es fundamental para recuperar la biomecánica de la rodilla, proporcionar una correcta estabilidad y funcionamiento libre de dolor, así como evitar cambios degenerativos tempranos. El objetivo del presente estudio fue valorar la recuperación funcional de los pacientes sometidos a una reconstrucción del ligamento cruzado anterior mediante ligamentoplastia con tendón semitendinoso-recto interno y sistema Toggelock. Material y métodos: Se diseñó un estudio retrospectivo descriptivo observacional, en el que se incluyeron a 29 pacientes a los cuales se les realizó una ligamentoplastia con semitendinoso-recto interno y sistema Togglelock en nuestro Centro, durante los años 2017-2018. Se estudiaron variables obtenidas de la historia clínica y la escala de Lysholm para la valoración del paciente. Resultados: En total, se obtuvo una muestra de 29 pacientes, 26 hombres y 3 mujeres con una media de edad de 31,13 años (rango 19-53). La rodilla más frecuentemente lesionada fue la derecha en 17 pacientes de 29, presentando lesiones asociadas el 65%. Una paciente había sufrido una fractura tibial intervenida con un clavo endomedular que alteró los resultados finales. La puntuación postquirúrgica de la escala de valoración subjetiva de Lysholm fue de 86. La movilidad de la rodilla intervenida presentó una reducción mínima de flexión de 6º en comparación con la rodilla no operada estadísticamente significativa. Conclusión: Los resultados obtenidos tras la reconstrucción del LCA con dicha técnica, utilizando la plastia del semitendinoso-recto interno y sistema Togglelock fueron buenos-excelentes, con un alto grado de satisfacción en los pacientes, escasas complicaciones y con resultados funcionales notables
Ligand-independent traffic of notch buffers activated armadillo in <em>Drosophila</em>
Notch receptors act as ligand-dependent membrane-tethered transcription factors with a prominent role in binary cell fate decisions during development, which is conserved across species. In addition there is increasing evidence for other functions of Notch, particularly in connection with Wnt signalling: Notch is able to modulate the activity of Armadillo/ß-catenin, the effector of Wnt signalling, in a manner that is independent of its transcriptional activity. Here we explore the mechanism of this interaction in the epithelium of the Drosophila imaginal discs and find that it is mediated by the ligand-independent endocytosis and traffic of the Notch receptor. Our results show that Notch associates with Armadillo near the adherens junctions and that it is rapidly endocytosed promoting the traffic of an activated form of Armadillo into endosomal compartments, where it may be degraded. As Notch has the ability to interact with and downregulate activated forms of Armadillo, it is possible that in vivo Notch regulates the transcriptionally competent pool of Armadillo. These interactions reveal a previously unknown activity of Notch, which serves to buffer the function of activated Armadillo and might underlie some of its transcription-independent effects
A Case Study of available methodology for the identification of Vulnerable Ecosystems/Habitats in bottom deep-sea fisheries: Possibilities to apply this method in the NAFO Regulatory Area in order to select Marine Protected Areas
Information is critical to Ecosystem Approach and to research about Vulnerable Marine Ecosystems/Habitats
(VME/Hs), fishing impacts on habitats and ad-hoc management measures are high-priority. Therefore, this paper
presents the ECOVUL/ARPA Interdisciplinary Approach, a case study of methodology for the identification of
VME/Hs in order to advise on conservation measures such as marine protected areas (MPAs). By means of an
interactive process involving Conventional Fisheries Science, Geomorphology, Sedimentology and Benthic
Ecology, the methodology developed under the ECOVUL/ARPA project, has been useful in order to contribute to
define practical criteria to the identification of VME/Hs, to improve the knowledge about VME/Hs distribution and
the adverse impacts of bottom trawl fisheries and to produce high quality advice on habitat protection. Applying an
interdisciplinary approach, the project identified the deep-water bottom trawl fishery footprint on the Hatton Bank
Western slope (NEAFC Regulatory Area), mapped the main fishing grounds and related seabed habitats and studied
the interactions between fishing and cold-water corals. This approach was used to suggest, with high level of
precision, the spatial limits of an area closed to bottom fishing, as an essential conservation measure to protect the
cold-water corals in the framework of the Ecosystem Approach to Fisheries management. We present here the
methods used, the main results obtained and discuss on the utility of this approach and the possibilities to apply it in
the NAFO Regulatory Area, with the aim to advise on measures for reducing the interactions of bottom fishing with
sensitive high-seas habitats and to contribute to implement the UNGA recommendations about habitat conservation
Geomorphology of the Avilés Canyon System, Cantabrian Sea (BayofBiscay)
The Avilés Canyon System (ACS) is a complex, structurally-controlled canyon and valley system constituted by three main canyons of different morphostructural character. They are, from east to west: La Gaviera Canyon, El Corbiro Canyon and Avilés Canyon. In addition to this ACS, a new canyon has been surveyed: Navia Canyon.
We present for the first time a high resolution multibeam map showing with great detail the morphological and structural complexity of this segment of the Cantabrian margin.
ACS presents a tectonic imprint marked by NW-SE, NNE-SSW and E-W structures. The morphology of their reaches as well as their single mouth, in addition to some rock dredges in their major valleys, demonstrates active down-slope flushing.
The continental shelf shows a flat, uniform slope with local and well defined rock outcrops south of Aviles Canyon head. Sedimentary zones are limited, showing thin unconsolidated sedimentary cover.
Strong continental margin water dynamics avoid thicker sediment deposition, being littoral sedimentary dynamics responsible for transport to the canyons heads and conduit to the Biscay Abyssal plain.
Biscay Abyssal Plain shows evidence of a strong westward current affecting the surveyed strip of this more than 10 km wide plain. Presence of two parallel deep sea channels, erosive scarps, and erosion of gully divides on the lower slope, may indicate that this is part of the distal fan at the termination of the large turbiditic system fed by Cap Ferret, Capbreton and other large canyons (Santander, Torrelavega, Lastres and Llanes) to the west of ACS.Instituto Español de OceanografíaVersión del edito
A first approach to assess the impact of bottom trawling over Vulnerable Marine Ecosystems on the High Seas of the Southwest Atlantic
Versión del edito
Diversity of fate outcomes in cell pairs under lateral inhibition
Cell fate determination by lateral inhibition via Notch/Delta signalling has been extensively studied. Most formalised models consider Notch/Delta interactions in fields of cells, with parameters that typically lead to symmetry breaking of signalling states between neighbouring cells, commonly resulting in salt-and-pepper fate patterns. Here we consider the case of signalling between isolated cell pairs, and find that the bifurcation properties of a standard mathematical model of lateral inhibition can lead to stable symmetric signalling states. We apply this model to the adult intestinal stem cell (ISC) of Drosophila, whose fate is stochastic but dependent on the Notch/Delta pathway. We observe a correlation between signalling state in cell pairs and their contact area. We interpret this behaviour in terms of the properties of our model in the presence of population variability in contact areas, which affects the effective signalling threshold of individual cells. Our results suggest that the dynamics of Notch/Delta signalling can contribute to explain stochasticity in stem cell fate decisions, and that the standard model for lateral inhibition can account for a wider range of developmental outcomes than previously considered
Novel highly luminescent amine-functionalized bridged silsesquioxanes
Amine-functionalized bridged silsesquioxanes (BSs) were synthesized from bis[(3-trimethoxysilyl)propyl] amine via a solvent-mediated route. BS-1 and BS-2 were obtained at neutral pH with sub- and stoichiometric amounts of water, respectively, and high tetrahydrofuran content. BS-3 was prepared with hyperstoichiometric water concentration, high tetrahydrofuran content, and hydrochloric acid. BS-4 was synthesized with hyperstoichiometric water concentration, high ethanol content, and sodium hydroxide. BS-1 and BS-2 were produced as transparent films, whereas BS-3 and BS-4 formed white powders. Face-to-face stacking of flat or folded lamellae yielded quasi-hydrophobic platelets with emission quantum yields of 0.05 ± 0.01 (BS-1 and BS-2) or superhydrophilic onion-like nanoparticles with exciting emission quantum yields of 0.38 ± 0.03 (BS-3) and 0.33 ± 0.04 (BS-4), respectively. The latter two values are the largest ever reported for amine-functionalized siloxane-based hybrids lacking aromatic groups. Fast Grotthus proton hopping between = [Formula: see text]/ = NH groups (BS-3) and = N-/ = NH groups (BS-4), promoted by H+ and OH- ions, respectively, and aided by short amine-amine contacts provided by the onion-like morphology, account for this unique optical behavior.This work was supported by Fundacao para a Ciencia e a Tecnologia (FCT)/MEC and FEDER (contracts UID/QUI/00616/2013, POCI-01-0145-FEDER-007491, and UID/Multi/00709/2013) and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement, project UniRCell (Ref. SAICTPAC/0032/2015, POCI-01-0145-FEDER-016422), and project LUMECD (Ref. PTDC/CTM/NAN/0956/20149 and POCI-01-0145-FEDER-016884). RP and MC acknowledge FCT for grants SFRH/BPD/87759/2012 and SFRH/BD/118466/2016, respectively. SN also acknowledges FCT for grants SFRH/BPD/63152/2009 and Post-PhD Fellowship of LUMECD project. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (FCT-Ref. UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement
Polymer Composites Containing Gated Mesoporous Materials for On-Command Controlled Release
Polyamidic nanofibrous membranes containing gated silica mesoporous particles, acting as carriers, are described as novel hybrid composite materials for encapsulation and on-command delivery of garlic extracts. The carrier system consists of MCM-41 solids functionalized in the outer surface, with linear polyamines (solid P1) and with hydrolyzed starch (solid P2), both acting as molecular gates. Those particles were adsorbed on electospun nylon-6 nanofibrous membranes yielding to composite materials M1 and M2. FE-SEM analysis confirmed the presence of particles incorporated on the nylon nanofibers. The release of the entrapped molecules (garlic extract) from the P1, P2, M1, and M2 materials was evaluated using cyclic voltammetry measurements. Electrochemical studies showed that at acidic pH P1 and M1 were unable to release their entrapped cargo (closed gate), whereas at neutral pH both materials release their loading (open gate). Dealing with P2 and M2 materials, in the absence of pancreatin a negligible release is observed (closed gate), whereas in the presence of enzyme the load is freely to diffuse to the solution. These newly developed composite nanomaterials, provide a homogeneous easy-to-handle system with controlled delivery and bioactive-protective features, having potential applications on pharmacology, medical and engineering fields.The authors wish to express their gratitude to the Generalitat Valenciana (Grisolia scholarship 2011/012, project PROM-ETEO/2009/016), Spanish Government (MINECO Projects AGL2012-39597-C02-01, AGL2012-39597-C02-02 and MAT2012-38429-C04-01) and the CIBER-BBN for their support. IILA thanks DISTAM and Universita degli di Milano for a specialization scholarship. We would also like to thank the Institut de Ciencia dels Materials (ICMUV) and to the Microscopy Service of the Universitat Politecnica de Valencia for technical support. We thank Roquette for the Glucidex samples.Acosta Romero, C.; Pérez Esteve, E.; Fuenmayor, CA.; Benedetti, S.; Cosio, MS.; Soto Camino, J.; Sancenón Galarza, F.... (2014). Polymer Composites Containing Gated Mesoporous Materials for On-Command Controlled Release. ACS Applied Materials and Interfaces. 6(9):6453-6460. https://doi.org/10.1021/am405939y645364606
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