New insights on the seismogenic potential of the Eastern Betic Shear Zone (SE Iberia): Quaternary activity and paleoseismicity of the SW segment of the Carrascoy Fault Zone

The Carrascoy Fault (CAF) is one of the main active faults that form part of the Eastern Betic Shear Zone, a 450 km fault system that accommodates most of the convergence between the Eurasian (Iberia) and Nubian plates in the Betic Cordillera, south Spain. Although the CAF represents a major earthquake threat to the nearby City of Murcia, studies on its Quaternary tectonics and seismogenic potential are scarce to date. We present evidence that supports the division of the CAF into two overlapping segments with contrasting tectonic structure, Quaternary activity, and landform control: a SW segment, characterized by a broad fold-and-thrust zone similar to the forebergs defined in the Gobi-Altai region, and a NE segment, characterized by a sharp mountain front controlled by strike-slip tectonics. We attribute the differentiation into these two segments to the stresses associated with topography, which in turn is a consequence of the shortening component, at the middle Pleistocene, after circa 217.4 ka. For the SW segment we infer the occurrence of 9 to 11, Mw 6.7 paleoearthquakes in the last 30.2 kyr, and a slip rate of 0.37 ± 0.08 m/kyr. We date the occurrence of the last surface rupture event after 2750 B.P., and we estimate an average recurrence period of major events of 3.3 ± 0.7 kyrThis work was supported by SISMOGEN (IGME, 2279) and FASEGEO (CGL2009-09726) research projects and a technical assistance of the Civil Protection Service of Murci

Biomechanics, obesity, and osteoarthritis. The role of adipokines: When the levee breaks

Osteoarthritis is a high-incidence painful and debilitating disease characterized by progressive degeneration of articular joints, which indicates a breakdown in joint homeostasis favoring catabolic processes. Biomechanical loading, associated with inflammatory and metabolic imbalances of joint, strongly contributes to the initiation and progression of the disease. Obesity is a primary risk factor for disease onset, and mechanical factors increased the risk for disease progression. Moreover, inflammatory mediators, in particular, adipose tissue-derived cytokines (better known as adipokines) play a critical role linking obesity and osteoarthritis. The present article summarizes the knowledge about the role of adipokines in cartilage and bone function, highlighting their contribution to the imbalance of joint homeostasis and, consequently, pathogenesis of osteoarthritis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:594-604, 2018

Effet du stress salin en milieu hydroponique sur le trèfle inoculé par le Rhizobium

Effects of salt stress in hydroponic media on clover plants inoculated with Rhizobium. The application of salt stress in hydroponic conditions on clover seedlings (Trifolium alexandrinum L.) inoculated with Rhizobium affected the nodulation starting from 2 g NaCl $\cdot$ l$^{-1}$, whereas the growth began to be reduced only from 4 g $\cdot$ l$^{-1}$. The growth of shoots was reduced by about 20% at 4 g $\cdot$ l$^{-1}$ and 44% at 6 g $\cdot$ l$^{-1}$. The development of the root system was less sensitive. This depressive effect on the growth was accompanied by biochemical and ultrastructural modifications. The soluble protein content of the leaves fell by about 75% at 6 g $\cdot$ l$^{-1}$ of NaCl. Proline and soluble sugars accumulated mainly in leaves, where they probably contributed to the osmotic adjustment phenomena. The transport and/or the utilization of starch was affected, so it accumulated in the chloroplasts. Salt stress also caused disorganization of the thylakoid membranes and an accumulation of lipidic globules inside the chloroplasts.L'application d'un stress salin en milieu hydroponique à des plantules de trèfle (Trifolium alexandrinum L.) inoculées par le Rhizobium affecte la nodulation à partir de 2 g $\cdot$ l$^{-1}$ NaCl alors que la croissance ne l'a été qu'à partir 4 g $\cdot$ l$^{-1}$. La croissance pondérale de la partie aérienne a été réduite de 20 % à 4 g $\cdot$ l$^{-1}$ et de 44 % à 6 g $\cdot$ l$^{-1}$. Le développement du système racinaire a été moins sensible. Cet effet dépressif sur la croissance s'est accompagné de modifications biochimiques et ultrastructurales. La teneur en protéines foliaires solubles a chuté d'environ 75 % à 6 g $\cdot$ l$^{-1}$ de NaCl. La proline et les sucres solubles se sont significativement accumulés dans les feuilles sous l'effet du sel. Ils participeraient aux phénomènes d'ajustement osmotique. Le transport ou/et l'utilisation de l'amidon ont été perturbés causant son accumulation dans les chloroplastes. Le stress salin a provoqué aussi une désorganisation des membranes thylakoïdiennes et une accumulation de globules lipidiques au niveau du stroma

Réponses physiologiques et biochimiques du trèfle (Trifolium alexandrinum L.) à la double association Mycorhizes-Rhizobium sous une contrainte saline

Physiological and biochemical responses to salt stress of mycorrhized and/or nodulated clover seedlings (Trifolium alexandrinum L.). Salt stress (0, 4, 6 and 8 g NaCl $\cdot$ L$^{-1}$) effects on arbuscular mycorrhized and/or nodulated clover (Trifolium alexandrinum L.) seedlings grown in greenhouse conditions under 75% field capacity were evaluated. The autochthonous mycorrhizal (AM) seedlings showed the best salt tolerance and biomass production improvement (+ 65%) for all the tested concentrations. AM root colonization was the highest (71%) and did not seem to be affected by salt doses. The double symbiosis (mycorrhization and nodulation) was found to be less efficient than single inoculations and revealed some antagonism between the fungus and Rhizobium. Phosphate nutrition was improved, mainly in the cases of single mycorrhized plants; this nutritional effect seems to be the main mechanism involved in salt tolerance. The leaf protein content was also improved by both types of symbiosis. Proline accumulated especially in the doubly inoculated (AM and Rhizobium) plants; meanwhile, sugars accumulated in the cases of single inoculations. However, the intensity of the salt stress showed a positive correlation with sugar accumulation for the plants which were only mycorrhized.L'effet de la salinité (0, 4, 6 et 8 g NaCl $\cdot$ L$^{-1}$) sur des plantules de trèfle (Trifolium alexandrinum L.) mycorhizées ou/et nodulées, cultivées sous serre sous une capacité au champ 75 %, a été estimé. La mycorhization par un inoculum mycorhizogène autochtone (MA) a abouti à une meilleure amélioration de la tolérance à la salinité et de la production de biomasse (+65 %) pour toutes les doses de sel appliquées. Les intensités de mycorhization et les teneurs en arbuscules obtenues pour les MA sont élevées (71 % et 57 %) et semblent non affectées par la dose de sel. La double symbiose (mycorhization et nodulation) s'est montrée moins efficace pour l'amélioration de la production de biomasse. Elle a révélé un antagonisme entre les deux symbiotes. La nutrition phosphatée a été significativement améliorée chez les plantes mycorhizées par les MA seuls. Cet effet nutritionnel semble jouer un rôle principal dans les mécanismes de tolérance à la salinité. Le contenu foliaire en protéines a été également amélioré dans le cas des deux symbioses. La proline s'est accumulée dans les feuilles du trèfle surtout chez les plantes doublement inoculées par les MA et le Rhizobium alors que les sucres solubles se sont accumulés suite aux inoculations simples. Toutefois, l'intensité du stress salin n'a montré de corrélation positive avec les teneurs accumulées en sucres que dans le cas des plantes mycorhizées

High resolution morphological changes of Cu, Ni, Al, and Au surfaces due to atmospheric corrosion

As atmospheric corrosion of electrical contacts is a common cause of failure in electronics industry and at the same time miniaturization is a requirement in any modern electronic device, it is important to study the effects of corrosion in the surface morphology of metals widely used in that industry sector, such as gold, copper, nickel, and aluminium. Here, atomic force microscopy (AFM) has been used with that purpose, analysing flat surfaces of those metals both before and after exposure by several weeks to the effects of a contaminated atmosphere containing both NO2 and SO2 at constant temperature and humidity. Results indicate all metals suffered changes both in surface morphology and roughness. AFM phase mode images also indicated the occurrence of different species on the Ni and Cu surfaces after 11 weeks of exposure. Evidence of defects due to the corrosion attack was only observed for Ni. © 2017 IEEE

Membrane remodeling capacity of a vesicle-inducing glycosyltransferase

Intracellular vesicles are abundant in eukaryotic cells but absent in the Gram-negative bacterium Escherichia coli. However, strong overexpression of a monotopic glycolipid-synthesizing enzyme, monoglucosyldiacylglycerol synthase from Acholeplasma laidlawii (alMGS), leads to massive formation of vesicles in the cytoplasm of E. coli. More importantly, alMGS provides a model system for the regulation of membrane properties by membrane-bound enzymes, which is critical for maintaining cellular integrity. Both phenomena depend on how alMGS binds to cell membranes, which is not well understood. Here, we carry out a comprehensive investigation of the membrane binding of alMGS by combining bioinformatics methods with extensive biochemical studies, structural modeling and molecular dynamics simulations. We find that alMGS binds to the membrane in a fairly upright manner, mainly by residues in the N-terminal domain, and in a way that induces local enrichment of anionic lipids and a local curvature deformation. Furthermore, several alMGS variants resulting from substitution of residues in the membrane anchoring segment are still able to generate vesicles, regardless of enzymatic activity. These results clarify earlier theories about the driving forces for vesicle formation, and shed new light on the membrane binding properties and enzymatic mechanism of alMGS and related monotopic GT-B fold glycosyltransferases. We characterize the membrane binding properties of the monotopic glycosyltransferase alMGS, and find that it binds in an upright manner and induces local enrichment of anionic lipids and local curvature deformations. These results shed new light on the ability of alMGS to induce intracellular vesicles upon overexpression, and on the enzymatic mechanism of alMGS and related GT-B fold glycosyltransferases. © 2014 FEBS.SCOPUS: ar.jFLWINinfo:eu-repo/semantics/publishe

Interference by nitrous acid decomposition in the kinetic study of nitrosation reactions

Under the acidic conditions of the stomach lumen, nitrosation reactions can occur in the human body between nitrite (added to meat because of its antibotulinic properties) and many compounds such as amino acids. From the results obtained, two conclusions can be drawn: (i) In the quantitative study of nitrosation reactions, it is necessary to take into account the competing reaction of HNO2 decomposition, which in some conditions is the dominant reaction; (ii) two alternative approaches based on the initial rate method are necessary to assess the weight of nitrous acid decomposition using taurine and homotaurine as nitrosatable substrates. In strongly acidic media, the decomposition reaction is dominant: In the case of taurine, the decomposition rate is negligible at pH ≥ 3.2. In the pH 3.2−2.5 range, decomposition is lower than nitrosation but not negligible, and at pH ≤ 2.5 decomposition is faster than nitrosation. With homotaurine, HNO2 decomposition is negligible at pH higher than 4.1. In the pH 4.1−2.8 range, nitrosation is faster but decomposition should be considered, and at pH ≤ 2.8 decomposition is the dominant reaction

Description of a bivalent cannabinoid ligand with hypophagic properties

A series of bivalent cannabinoid ligands is proposed. The synthesis of double amides based on the rimonabant structure separated by an alkyl chain and the evaluation of their affinities for cannabinoid receptors are reported. The data of 4d confirmed that a bivalent structure is a suitable scaffold for CB1 cannabinoid receptor binding. The compound 4d was selected for in vitro and in vivo pharmacological evaluations. Moreover, intraperitoneal administration of 4d to food-deprived rats resulted in a dose-dependent inhibition of feeding that was maintained up to 240 min. A series of bivalent cannabinoid ligands was synthesized. The data of 4d confirmed that a bivalent structure is a suitable scaffold for CB1 cannabinoid receptor binding. The compound 4d was selected for in vitro and in vivo pharmacological evaluations. Moreover, intraperitoneal administration of 4d to food-deprived rats resulted in a dose-dependent inhibition of feeding that was maintained up to 240 min. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Peer Reviewe

Virtual array beamforming of GPS TEC observations of coseismic ionospheric disturbances near the Geomagnetic South Pole triggered by teleseismic megathrusts

We identified coseismic ionospheric disturbances (CID) in Antarctica generated by the 2010 Maule and the 2011 Tohoku-Oki earthquakes analyzing total electron content (TEC) data with a modified beamforming technique. Beamforming in Antarctica, however, is not straightforward due to the effects of array deformation and atmospheric neutral wave-ionospheric plasma coupling. We take these effects into account and present a method to invert for the seismically generated acoustic wave using TEC observations. The back azimuths, speeds, and waveforms obtained by the beamform are in excellent agreement with the hypothesis that the TEC signals are generated by the passage of Rayleigh waves from the Maule and Tohoku-Oki earthquakes. The Tohoku-Oki earthquake is ~12,500 km from Antarctica, making this the farthest observation of CIDs to date using GPS

Cytotoxic effects induced by combination of heliantriol B2 and dequalinium against human leukemic cell lines

Natural occurring compounds are considered an important source of antitumoral agents. In the present study, the cytotoxic potential of three pentacyclic triterpenes isolated from Chuquiraga erinacea (Asteraceae), against the human leukemic cell lines NB4 and K562 was assessed. Heliantriol B2 (HB2) showed the highest cytotoxic activity after 24 h treatment showing IC 50 values of 1.98 ± 0.12 μm and 3.52 ± 0.14 μm for NB4 and K562 cells, respectively. This activity was higher than that of the reference compound dequalinium (DQA). Apoptosis and necrosis induced by HB2 in both NB4 and K562 cell lines were analysed by Annexin V/PI labeling. Mitochondrial alterations including reactive oxygen species (ROS) production and mitochondrial transmembrane potential (Δψm) were also tested. The results demonstrated that HB2 induced cell death by apoptosis and necrosis and showed enhanced cytotoxic effects in combination with DQA. Besides, HB2 induced ROS overproduction in NB4 cells and a slight decrease of Δψm. Consequently, our findings prompt further studies on the HB2 mechanism of action and its selectivity to tumor cells in order to assess the potential of HB2 as an agent for cancer treatment. Copyright © 2010 John Wiley & Sons, Ltd.Fil: Vela Gurovic, Maria Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; Argentina. Universidad de Alcalá; EspañaFil: Díaz Lanza, A. María. Universidad de Alcalá; EspañaFil: Boyano Adánez, María Del Carmen. Universidad de Alcalá; EspañaFil: Estañ Omaña, M. Cristina. Universidad de Alcalá; EspañaFil: Gañán Gõmez, Irene. Universidad de Alcalá; EspañaFil: Murray, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Química del Sur. Universidad Nacional del Sur. Departamento de Química. Instituto de Química del Sur; ArgentinaFil: Sancho Lõpez, Pilar. Universidad de Alcalá; Españ