Asociaciones de peces profundos en el Mediterráneo

[EN] Data collected during the DESEAS survey carried out in three areas of the Mediterranean Sea (Balearic Sea, western and eastern Ionian Sea) were used to describe the structure and spatial distribution of the fish assemblages at depths between 600 and 4000 m. A total of 55 species (8 chondrichthyes and 47 teleost fish) were sampled, 38 of them in the Balearic Sea, 30 in the western Ionian and 37 in the eastern Ionian. Multivariate analysis showed a clear pattern of zonation with depth and geographic area. Three main assemblages were identified across the vertical gradient investigated: on the upper slope around a depth of 600 m, on the middle slope between 800 and 1300 m, and on the lower slope below 1300 m. The geographic characterisation of the ichthyofauna structure was mainly observed on the upper and middle slope. The highest abundance and biomass values were found at depths of 1000-1200 m due to the presence of larger species with high energy requirements, such as Alepocephalusrostratus, Mora moro and Galeus melastomus. On the middle slope, significant differences in the abundance, biomass and mean fish weight were detected between the three areas. Significant differences for these parameters were also shown between the middle and lower slope assemblages. A significant decrease in species richness and diversity was shown with increasing depth, indicating an impoverishment of the megafauna with depth and a higher similarity between the Balearic Sea and the Ionian Sea with regard to the greatest depths. The dominant species on the deepest bottoms were Bathypteroismediterraneus, Chalinura mediterranea and Coryphaenoides guentheri. On the lower slope, the shark Centroscymnuscoelolepis was also found to be relatively abundant off the Balearic Islands, Etmopterusspinax in the eastern Ionian Sea and the teleost fish Cataetyx laticeps throughout the three study areas. The deepest bottoms of the Mediterranean Sea shelter an ichthyofauna dominated by small-medium species living in a food scarce environment in which some large mobile fishes are widespread. The results are discussed in relation to previous studies mostly carried out in the Atlantic and western Mediterranean[ES] A partir de datos recolectados durante la campaña DESEAS, llevada a cabo en tres áreas del mar Mediterráneo (Mar Balear y Iónico occidental y oriental), se describe la estructura y la distribución espacial de las asociaciones de peces entre 600 y 4000 m de profundidad. Se obtuvieron un total de 55 especies (8 condrictrios y 47 peces teleósteos), 38 de los cuales procedían del mar Balear, 30 del Iónico occidental y 37 del oriental. El análisis multivariante de los datos nos muestra un claro patrón en zonación tanto en profundidad como por área geográfica. Se identificaron tres asociaciones principales a través del gradiente batimétrico estudiado: en el talud superior a profundidades alrededor de los 600 m, en el talud medio entre 800 y 1300 m, y en el talud inferior por debajo de los 1300 m. La caracterización geográfica de la estructura de la ictiofauna se observó principalmente en el talud superior y medio. A profundidades comprendidas entre 1000 y 1200 m fue donde se encontraron los mayores valores de biomasa, debido a la presencia de especies más grandes y con mayores requerimientos energéticos como Alepocephalus rostratus, Mora moro y Galeus melastomus. En el talud medio se detectaron diferencias significativas en abundancia, biomasa y peso medio de los peces entre las tres áreas. También se encontraron en las asociaciones de peces diferencias significativas en estos parámetros en el talud superior e inferior. Con el aumento de profundidad se detecta una disminución de la riqueza específica y la diversidad, indicando un empobrecimiento de la magafauna con la profundidad. Sin embargo se observa alta similaridad entre las áreas de estudio y en las máximas profundidades alcanzadas. Las especies dominantes en los fondos más profundos fueron: Bathypterois mediterraneus, Chalinura mediterranea y Coryphaenoides guentheri. En el talud inferior del mar Balear, el tiburón Centroscymnus coelolepis fue también relativamente abundante. Etmopterus spinax en el Iónico oriental y el teleosteo Cataetyx laticeps en las tres áreas de estudio. Los fondos más profundos del Mediterráneo son refugio para una ictiofauna dominada por pequeñas y medianas especies que habitan en en un ambiente escaso de alimento, en el cual solo algunos grandes peces móviles pueden extenderse. Los resultados se discuten en relación a estudios previos llevados a cabo mayoritariamente en el Atlántico y Mediterráneo occidentalThis work was supported by the Directorate General of Fisheries of the European Commission as part of the project DESEAS (Exploratory survey to collect data of the exploited and virgin stocks of deep-sea shrimp A. antennatus, of interest to the CFP - Study Contract nº 2000/39, DGXIV)Peer reviewe

Stress-Induced Reinstatement of Drug Seeking: 20 Years of Progress

In human addicts, drug relapse and craving are often provoked by stress. Since 1995, this clinical scenario has been studied using a rat model of stress-induced reinstatement of drug seeking. Here, we first discuss the generality of stress-induced reinstatement to different drugs of abuse, different stressors, and different behavioral procedures. We also discuss neuropharmacological mechanisms, and brain areas and circuits controlling stress-induced reinstatement of drug seeking. We conclude by discussing results from translational human laboratory studies and clinical trials that were inspired by results from rat studies on stress-induced reinstatement. Our main conclusions are (1) The phenomenon of stress-induced reinstatement, first shown with an intermittent footshock stressor in rats trained to self-administer heroin, generalizes to other abused drugs, including cocaine, methamphetamine, nicotine, and alcohol, and is also observed in the conditioned place preference model in rats and mice. This phenomenon, however, is stressor specific and not all stressors induce reinstatement of drug seeking. (2) Neuropharmacological studies indicate the involvement of corticotropin-releasing factor (CRF), noradrenaline, dopamine, glutamate, kappa/dynorphin, and several other peptide and neurotransmitter systems in stress-induced reinstatement. Neuropharmacology and circuitry studies indicate the involvement of CRF and noradrenaline transmission in bed nucleus of stria terminalis and central amygdala, and dopamine, CRF, kappa/dynorphin, and glutamate transmission in other components of the mesocorticolimbic dopamine system (ventral tegmental area, medial prefrontal cortex, orbitofrontal cortex, and nucleus accumbens). (3) Translational human laboratory studies and a recent clinical trial study show the efficacy of alpha-2 adrenoceptor agonists in decreasing stress-induced drug craving and stress-induced initial heroin lapse

Impact of Artemisinin-Based Combination Therapy and Insecticide-Treated Nets on Malaria Burden in Zanzibar

Zanzibar has implemented artemisinin-based combination therapy for uncomplicated malaria, plus long-lasting insecticidal nets. Achuyt Bhattarai and colleagues found malaria morbidity and mortality decreased dramatically within two years

Influence of Rapid Malaria Diagnostic Tests on Treatment and Health Outcome in Fever Patients, Zanzibar—A Crossover Validation Study

Anders Bjorkman and colleagues report results from a cross-over trial evaluating rapid diagnostic testing for malaria diagnosis in Zanzibar

Pth4, an ancient parathyroid hormone lost in eutherian mammals, reveals a new brain-to-bone signaling pathway

Regulation of bone development, growth, and remodeling traditionally has been thought to depend on endocrine and autocrine/paracrine modulators. Recently, however, brain-derived signals have emerged as key regulators of bone metabolism, although their mechanisms of action have been poorly understood. We reveal the existence of an ancient parathyroid hormone (Pth)4 in zebrafish that was secondarily lost in the eutherian mammals' lineage, including humans, and that is specifically expressed in neurons of the hypothalamus and appears to be a central neural regulator of bone development and mineral homeostasis. Transgenic fish lines enabled mapping of axonal projections leading from the hypothalamus to the brainstem and spinal cord. Targeted laser ablation demonstrated an essential role for of pth4-expressing neurons in larval bone mineralization. Moreover, we show that Runx2 is a direct regulator of pth4 expression and that Pth4 can activate cAMP signaling mediated by Pth receptors. Finally, gain-of-function experiments show that Pth4 can alter calcium/phosphorus levels and affect expression of genes involved in phosphate homeostasis. Based on our discovery and characterization of Pth4, we propose a model for evolution of bone homeostasis in the context of the vertebrate transition from an aquatic to a terrestrial lifestyle.Spanish Economy and Competitiveness Ministry Project [ALG2011-23581, AGL2014-52473R]; Portuguese Foundation for Science and Technology [PTDC/BIA-ANM/4225/2012-phos-fate]; U. S. National Institutes of Health/Office of the Director Grant [R01OD011116, R01 RR020833]; Generalitat de Catalunya [SGR2014-290]; Spanish Economy and Competitiveness Ministry [BFU2010-14875]; Science and Innovation Ministry [AGL2010-22247-C03-01]; Campus do Mar Ph.D. grant; Xunta de Galicia (Santiago, Spain) [AGL2014-52473R]info:eu-repo/semantics/publishedVersio

The OpenMolcas Web: A Community-Driven Approach to Advancing Computational Chemistry

The developments of the open-source OpenMolcas chemistry software environment since spring 2020 are described, with a focus on novel functionalities accessible in the stable branch of the package or via interfaces with other packages. These developments span a wide range of topics in computational chemistry and are presented in thematic sections: electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report offers an overview of the chemical phenomena and processes OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations

Behavioral and Endocrine Consequences of Simultaneous Exposure to Two Different Stressors in Rats: Interaction or Independence?

Although behavioral and endocrine consequences of acute exposure to stressors have been extensively studied, little is known about how simultaneous exposure to two different stressors interacts to induce short- and long-term effects. In the present experiment we studied this interaction in adult male rats exposed to cat fur odor (impregnated cloth) or immobilization on boards either separately or simultaneously. We reasoned that exposure to the odor of a potential predator while immobilized, may potentiate its negative consequences as compared to exposure to only one of the stressors. Exposure to cat odor elicited the expected reduction of activity and avoidance of the area where the impregnated cloth was located. The endocrine response (plasma levels of ACTH and corticosterone, as a measure of the hypothalamic-pituitary-adrenal axis, HPA) was markedly greater after immobilization than after cat fur odor and no additive effects were found by simultaneous exposure to both stressors. Cat odor, but not immobilization, increased anxiety-like behavior as evaluated in the elevated plus-maze 7 days after the stressors, with no evidence of enhanced HPA activation. In addition, cat odor exposure resulted in long-lasting (8 days later) fear conditioning to the box containing a clean cloth, which was reflected by hypoactivity, avoidance of the cloth area and enhanced HPA activation. All these effects were similarly observed in rats exposed simultaneously to cat odor and immobilization. In rats only exposed to immobilization, only some weak behavioral signs of fear conditioning were found, but HPA activation in response to the context paired to immobilization was enhanced to the same extent as in cat odor-exposed animals, supporting a certain degree of endocrine conditioning. The present results did not reveal important behavioral interactions between the two stressors when animals experienced both simultaneously, whereas some interactions were found regarding HPA activation. Theoretical implications are discussed

The role of SPARC in extracellular matrix assembly

SPARC is a collagen-binding matricellular protein. Expression of SPARC in adult tissues is frequently associated with excessive deposition of collagen and SPARC-null mice fail to generate a robust fibrotic response to a variety of stimuli. This review summarizes recent advancements in the characterization of the binding of SPARC to collagens and describes the results of studies that implicate a function for SPARC in the regulation of the assembly of basal lamina and fibrillar collagen in the ECM. Potential cellular mechanisms that underlie SPARC activity in ECM deposition are also explored

Chemical diplomacy in male tilapia: urinary signal increases sex hormone and decreases aggression

Androgens, namely 11-ketotestosterone (11KT), have a central role in male fish reproductive physiology and are thought to be involved in both aggression and social signalling. Aggressive encounters occur frequently in social species, and fights may cause energy depletion, injury and loss of social status. Signalling for social dominance and fighting ability in an agonistic context can minimize these costs. Here, we test the hypothesis of a 'chemical diplomacy' mechanism through urinary signals that avoids aggression and evokes an androgen response in receiver males of Mozambique tilapia (Oreochromis mossambicus). We show a decoupling between aggression and the androgen response; males fighting their mirror image experience an unresolved interaction and a severe drop in urinary 11KT. However, if concurrently exposed to dominant male urine, aggression drops but urinary 11KT levels remain high. Furthermore, 11KT increases in males exposed to dominant male urine in the absence of a visual stimulus. The use of a urinary signal to lower aggression may be an adaptive mechanism to resolve disputes and avoid the costs of fighting. As dominance is linked to nest building and mating with females, the 11KT response of subordinate males suggests chemical eavesdropping, possibly in preparation for parasitic fertilizations.info:eu-repo/semantics/publishedVersio

Photo-Active Biological Molecular Materials: From Photoinduced Dynamics to Transient Electronic Spectroscopies

We present an overview of a methodology for the simulation of the photo-response of biological (macro)molecules, designed around a Quantum Mechanics / Molecular Mechanics (QM/MM) subtractive scheme. The resulting simulation workflow, that goes from the characterization of the photo-active system to the modeling of (transient) electronic spectroscopies is implemented in the software COBRAMM, but is completely general and can be used in the framework of any specific QM/MM implementation. COBRAMM is a smart interface to existing state-of-the-art theoretical chemistry codes, combining different levels of description and different algorithms to realize tailored problem-driven computations. The power of this approach is illustrated by reviewing the studies of two fundamental problems involving biological light-sensitive molecules. First, we will consider the photodynamics of the retinal molecule, the pigment of rhodopsin, a visual receptor protein contained in the rod cells of the retina. Retinal, with its light-induced isomerization, triggers a cascade of events leading to the production of the nerve impulse. Then, we will review some studies focusing on the interaction of DNA systems with ultraviolet (UV) light, a problem that has become one of the benchmark for the development of nonlinear spectroscopy, because of the ultrashort excited state lifetimes that arise from very efficient radiationless excited state decay and consent self-protection of DNA against UV damage