9 research outputs found
Día mundial del sonido, 22 de octubre: Una iniciativa nacional para una efeméride mundial
El Día Mundial del Sonido es el día del Sonido Positivo y se entiende por sonido
positivo el que sirve al ser humano para conocerse mejor
a sí mismo y a su especie, para sobrevivir, para inspeccionar
su entorno, obteniendo toda una variada gama de
información. Como sabemos, el sonido positivo está presente
en nuestras vidas en todos sus aspectos. Es percibido
desde antes del nacimiento por el ser humano,
preparado desde entonces para distinguir una cantidad
infinita de ellos, e indica la fuente donde surge: el tipo de
objeto, el material del que está compuesto éste, el tipo
de animal y su circunstancia, el rol del humano, el lugar
donde se produce e incluso parámetros temporales en
los que tiene lugar. Es un sonido, pues, no solamente
necesario, sino imprescindible. Permite conocer procesos
y prever el desarrollo de los mismos, a fin de tomar
decisiones oportunas. Así pues, el sonido positivo define,
informa, alerta sobre el material o el lugar donde se produce,
sobre quién lo produce y por qué, completa información,
contextualiza el lugar, adelanta circunstancias;
organiza convenientemente, y permite dar elementos de
disfrute, y entreteniendo.Daumal Domènech, F.; Cerdà I Ferrer, J.; Luceño Ramos, M.; Giménez Pérez, A. (2014). Día mundial del sonido, 22 de octubre: Una iniciativa nacional para una efeméride mundial. Revista de Acústica. 45(1):51-54. http://hdl.handle.net/10251/47746S515445
As and S speciation in a submarine sulfide mine tailings deposit and its environmental significance: The study case of Portmán Bay (SE Spain)
The dumping of an estimated amount of 57 million tons of hazardous sulfide mine waste from 1957 to 1990 into Portmán's Bay (SE Spain) caused one of the most severe cases of persistent anthropogenic impact in Europe's costal and marine environments. The resulting mine tailings deposit completely infilled Portmán's Bay and extended seawards on the continental shelf, bearing high levels of metals and As. The present work, where Synchrotron XAS, XRF core scanner and other data are combined, reveals the simultaneous presence of arsenopyrite (FeAsS), scorodite (FeAsO₄·2H₂O), orpiment (As2S3) and realgar (AsS) in the submarine extension of the mine tailings deposit. In addition to arsenopyrite weathering and scorodite formation, the, the presence of realgar and orpiment is discussed, considering both potential sourcing from the exploited ores and in situ precipitation from a combination of inorganic and biologically mediated geochemical processes. Whereas the formation of scorodite relates to the oxidation of arsenopyrite, we hypothesize that the presence of orpiment and realgar is associated to scorodite dissolution and subsequent precipitation of these two minerals within the mine tailings deposit under moderately reducing conditions. The occurrence of organic debris and reduced organic sulfur compounds evidences the activity of sulfate-reducing bacteria (SRB) and provides a plausible explanation to the reactions leading to the formation of authigenic realgar and orpiment. The precipitation of these two minerals in the mine tailings, according to our hypothesis, has important consequences for As mobility since this process would reduce the release of As into the surrounding environment. Our work provides for the first time valuable hints on As speciation in a massive submarine sulfide mine tailings deposit, which is highly relevant for similar situations worldwide
In situ structural characterization of early amyloid aggregates in Alzheimer's disease transgenic mice and Octodon degus
Altres ajuts: ALBA Synchrotron subvenció del projecte intern (IH18MIRAS); ERDF program Interreg Poctefa (RedPrion 148/16)Amyloid plaques composed of Aβ amyloid peptides and neurofibrillary tangles are a pathological hallmark of Alzheimer's disease. In situ identification of early-stage amyloid aggregates in Alzheimer's disease is relevant for their importance as potential targets for effective drugs. Synchrotron-based infrared imaging is here used to identify early-stage oligomeric/granular aggregated amyloid species in situ in the brain of APP/PS1 transgenic mice and Octodon degus for the first time. Also, APP/PS1 mice show fibrillary aggregates at 6 and 12 months whereas very little formation of fibrils is found in aged Octodon degus. Finally, significant decreased burden of early-stage aggregates and fibrillary aggregates is obtained following treatment with G4-His-Mal dendrimers (a neurodegenerative protector) in 6-month-old APP/PS1 mice, thus demonstrating putative therapeutic properties of G4-His-Mal dendrimers in AD models. Identification, localization, and characterization using infrared imaging of these non-fibrillary species in the cerebral cortex at early stages of AD progression in transgenic mice point to their relevance as putative pharmacological targets. No less important, early detection of these structures may be useful in the search for markers for non-invasive diagnostic techniques
Poly(propylene imine) dendrimers with histidine-maltose shell as novel type of nanoparticles for synapse and memory protection.
Poly(propylene imine) dendrimers have been shown to be promising 3-dimensional polymers for the use in the pharmaceutical and biomedical applications. Our aims of this study were first, to synthesize a novel type of dendrimer with poly(propylene imine) core and maltose-histidine shell (G4HisMal) assessing if maltose-histidine shell can improve the biocompatibility and the ability to cross the blood brain barrier, and second, to investigate the potential of G4HisMal to protect Alzheimer disease transgenic mice from memory impairment. Our data demonstrate that G4HisMal has significantly improved biocompatibility and ability to cross the blood brain barrier in vivo. Therefore, we suggest that a maltose-histidine shell can be used to improve biocompatibility and ability to cross the blood brain barrier of dendrimers. Moreover, G4HisMal demonstrated properties for synapse and memory protection when administered to Alzheimer disease transgenic mice. Therefore, G4HisMal can be considered as a promising drug candidate to prevent Alzheimer disease via synapse protection
Poly(propylene imine) dendrimers with histidine-maltose shell as novel type of nanoparticles for synapse and memory protection
Poly(propylene imine) dendrimers have been shown to be promising 3-dimensional polymers for the use in the pharmaceutical and biomedical applications. Our aims of this study were first, to synthesize a novel type of dendrimer with poly(propylene imine) core and maltose-histidine shell (G4HisMal) assessing if maltose-histidine shell can improve the biocompatibility and the ability to cross the blood-brain barrier, and second, to investigate the potential of G4HisMal to protect Alzheimer disease transgenic mice from memory impairment. Our data demonstrate that G4HisMal has significantly improved biocompatibility and ability to cross the blood-brain barrier in vivo. Therefore, we suggest that a maltose-histidine shell can be used to improve biocompatibility and ability to cross the blood-brain barrier of dendrimers. Moreover, G4HisMal demonstrated properties for synapse and memory protection when administered to Alzheimer disease transgenic mice. Therefore, G4HisMal can be considered as a promising drug candidate to prevent Alzheimer disease via synapse protection
Multiproxy characterization of sedimentary facies in a submarine sulphide mine tailings dumping site and their environmental significance: The study case of Portmán Bay (SE Spain)
Mining activities are essential to our society, but ore extraction and treatment produce waste that must be stored in safe places without harm to the environment. For a long time, seafloor disposal has been viewed as a cheap option with barely visible impacts. In Portmán Bay, SE of Spain, large amounts of tailings from open pit sulphide mining were discharged directly into the coastal sea over 33 years, thus forming a massive deposit that completely infilled the bay and expanded seawards over the inner continental shelf. Here we present the first multiproxy physicochemical characterization of the submarine tailings in Portmán Bay, mostly by using nondestructive techniques, also including pre-dumping and post-dumping sediments. Eight distinct sedimentary facies, grouped in four stratigraphic units, have been thus identified in a set of up to 4.3 m long gravity cores totalling more than 60 m. Geogenic and anthropogenic geochemical proxies consistently allow differentiating pre-dumping sediments from tailings. Potentially toxic metals if made bioavailable can reach high concentrations in units including or formed exclusively by tailings (i.e. up to 3455, 2755 and 1007 mg kg−1 for Pb, As, and Zn, respectively). Some physical properties, such as magnetic susceptibility, are particularly useful as the tailings are rich in Fe-bearing minerals (>30% Fe in some layers). Estimated sedimentation rates show a strong gradient from proximal to distal locations, with rates in excess of 50 cm yr−1 to less than 1 cm yr−1 . We ultimately document the history of the transformation of Portmán Bay from an almost natural state to a new conditio
Myoglobinopathy is an adult-onset autosomal dominant myopathy with characteristic sarcoplasmic inclusions
Myoglobin, encoded by MB, is a small cytoplasmic globular hemoprotein highly expressed in cardiac myocytes and oxidative skeletal myofibers. Myoglobin binds O facilitates its intracellular transport and serves as a controller of nitric oxide and reactive oxygen species. Here, we identify a recurrent c.292C>T (p.His98Tyr) substitution in MB in fourteen members of six European families suffering from an autosomal dominant progressive myopathy with highly characteristic sarcoplasmic inclusions in skeletal and cardiac muscle. Myoglobinopathy manifests in adulthood with proximal and axial weakness that progresses to involve distal muscles and causes respiratory and cardiac failure. Biochemical characterization reveals that the mutant myoglobin has altered O binding, exhibits a faster heme dissociation rate and has a lower reduction potential compared to wild-type myoglobin. Preliminary studies show that mutant myoglobin may result in elevated superoxide levels at the cellular level. These data define a recognizable muscle disease associated with MB mutation