88 research outputs found

    Trichomycterus rosablanca (Siluriformes, Trichomycteridae) una especie nueva de bagre hipogeo de los Andes colombianos

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    Trichomycterus rosablanca is described as a new troglobitic catfish species from caves in southeastern Santander, Colombia. These caves are drained by the Carare River of the Magdalena River basin. The new species is characterized by the advanced condition in the typical troglomorphisms found in other congeneric cave-dwelling species, such as absence of eyes and pigmentation. Trichomycterus rosablanca is diagnosed by the following putative autapomorphies: 1) presence of a circular foramen in the main body of the interopercle, dorsal to the interopercular plate supporting the odontodes, and 2) presence of a single sensory pore in the posteriormost section of the infraorbital canal. Trichomycterus rosablanca can be distinguished from all known Trichomycterus species from Colombia by having the supraorbital canal interrupted in the nasal section, resulting in the pattern of s1, s2, s3, and s6 sensory pores, and the lachrimal/antorbital bone not enclosing the anteriormost section of the infraorbital canal. The genetic distinctiveness of Trichomycterus rosablanca is confirmed by GMYC and genetic distance method analyses of the cytochrome C oxidase subunit I gene sequence. The description of this species places Colombia as the second most diverse country in the continent in terms of number of cave fish species and calls the  attention on the conservation efforts needed to guarantee the permanence of this remarkable diversity of hypogean fishes. Se describe Trichomycterus rosablanca, una especie nueva de bagre troglobio de cuevas en el suroriente de Santander, Colombia. Estas cuevas son drenadas por el río Carare, de la cuenca del río Magdalena. La especie nueva se caracteriza por la condición avanzada en los troglomorfismos típicos encontrados en otros congéneres habitantes de cuevas, como ausencia de ojos y pigmentación. Trichomycterus rosablanca es diagnosticado por las siguientes autapomorfías putativas: 1) presencia de un foramen circular enel cuerpo principal del interopérculo, dorsal a la placa interopercular soportando los odontodes, y 2) presencia de un único poro sensorial en la sección más posterior del canal infraorbital. Trichomycterus rosablanca puede ser distinguida de todas las especies conocidas de Trichomycterus de Colombia por tener el canal supraorbital interrumpido en la sección nasal, resultando en el patrón de poros sensoriales s1, s2, s3 y s6 y el hueso lacrimal/antorbital no encerrando la sección más anterior del canal infraorbital. La identidad genética de Trichomycterus rosablanca es confirmada por análisis GMYC y de distancia genética de la secuencia génica de la subunidad I de la citocromo C oxidasa. La descripción de esta especie ubica a Colombia como el segundo país más diverso en el continente en términos del número de especies de peces cavernícolas y llama la atención sobre los esfuerzos de conservación necesarios para garantizar la permanencia de esta extraordinaria diversidad de peces hipogeos

    A Target Enrichment Bait Set for Studying Relationships among Ostariophysan Fishes

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    © 2020 by the American Society of Ichthyologists and Herpetologists. Target enrichment of conserved nuclear loci has helped reconstruct evolutionary relationships among a wide variety of species. While there are preexisting bait sets to enrich a few hundred loci across all fishes or a thousand loci from acanthomorph fishes, no bait set exists to enrich large numbers (\u3e1,000 loci) of ultraconserved nuclear loci from ostariophysans, the second largest actinopterygian superorder. In this study, we describe how we designed a bait set to enrich 2,708 ultraconserved nuclear loci from ostariophysan fishes by combining an existing genome assembly with low coverage sequence data collected from two ostariophysan lineages. We perform a series of enrichment experiments using this bait set across the ostariophysan tree of life, from the deepest splits among the major groups (\u3e150 Ma) to more recent divergence events that have occurred during the last 50 million years. Our results demonstrate that the bait set we designed is useful for addressing phylogenetic questions from the origin of crown ostariophysans to more recent divergence events, and our in silico results suggest that this bait set may be useful for addressing evolutionary questions in closely related groups of fishes, like Clupeiformes

    Molecular species delimitation and description of a new species of Phenacogaster (Teleostei, Characidae) from the southern Amazon basin

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    Phenacogaster is the most species-rich genus of the subfamily Characinae with 23 valid species broadly distributed in riverine systems of South America. Despite the taxonomic diversity of the genus, little has been advanced about its molecular diversity. A recent molecular phylogeny indicated the presence of undescribed species within Phenacogaster that is formally described here. We sampled 73 specimens of Phenacogaster and sequenced the mitochondrial cytochrome c oxidase subunit I (COI) gene in order to undertake species delimitation analyses and evaluate their intra- and interspecific genetic diversity. The results show the presence of 14 species, 13 of which are valid and one undescribed. The new species is known from the tributaries of the Xingu basin, the Rio das Mortes of the Araguaia basin, and the Rio Teles Pires of the Tapajós basin. It is distinguished by the incomplete lateral line, position of the humeral blotch near the pseudotympanum, and shape of the caudal-peduncle blotch. Meristic data and genetic differentiation relative to other Phenacogaster species represent strong evidence for the recognition of the new species and highlight the occurrence of an additional lineage of P. franciscoensis

    Características morfo-arquitecturales y fenológicas de Ugni molinae (Myrtaceae): una especie arbustiva andino-patagónica con frutos comestibles

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    Background and aims: Ugni molinae (Myrtaceae) is a shrub species native to southern Chile − where it is known as “murta” or “murtilla” − and Argentina. This study was aimed at providing morpho-architectural information about U. molinae so as to promote its cultivation and introduction in productive systems of Argentina. M&M: Observations of U. molinae were performed at different scales (plants, foliated axes and annual shoots) for plants developed in natural populations and plants derived from seeds and stem cuttings sampled at the Lago Puelo National Park and its surroundings (Chubut province, Argentina) and grown in nurseries for five years. Results: Short annual shoots of U. molinae complete their extension without branching, whereas long annual shoots may, as they extend, develop branches from intermediate and/or distal nodes. Flowering may start from the second or third year after seed germination or cut rooting. Most flowers develop at the end of spring from basal nodes of growing shoots. Plant structure changes from a clearly hierarchical to a non-hierarchical architecture in the first years of growth.  Conclusions: Ugni molinae may be multiplied easily from stem cuttings and seed germination. A short internode and small green leaves associated with it are clear markers of a limit between two successive annual shoots. More detailed studies about the development and productivity of this species in Argentina are necessary in order to evaluate the factibility of its inclusion in productive systems.Introducción y objetivos: Ugni molinae (Myrtaceae) es una especie arbustiva nativa del sur de Chile − donde se la conoce como “murta” o “murtilla” − y de Argentina. Este estudio tiene como objetivo aportar información morfo-arquitectural de U. molinae, y así promover su cultivo e introducción en sistemas productivos de Argentina. M&M: Se realizaron observaciones de U. molinae a diferentes niveles (planta completa, ejes y brotes anuales) sobre plantas desarrolladas en poblaciones naturales y plantas derivadas de semillas o de enraizamiento de estacas y mantenidas en viveros por cinco años. Resultados: Los brotes cortos de U. molinae completan su extensión sin ramificarse, mientras que los brotes de mayor longitud pueden ramificarse durante su alargamiento a partir de nudos intermedios y/o distales. El inicio de la floración se produce a partir del segundo al tercer año desde la germinación de una semilla o del enraizamiento de una estaca. La mayoría de las flores se forman a fines de la primavera a partir de nudos basales de brotes en alargamiento. La arquitectura de las plantas cambia desde claramente jerárquica a no-jerárquica en los primeros años de desarrollo.  Conclusiones: Ugni molinae puede multiplicarse con facilidad a partir del enraizamiento de estacas o de germinación de semillas. El desarrollo de un entrenudo corto asociado a hojas verdes pequeñas es un claro indicador del límite entre brotes anuales sucesivos. Se necesitan estudios más detallados acerca del desarrollo y la productividad de esta especie en la Argentina para evaluar su inclusión en sistemas productivos

    Cognitive vulnerability in mental disorders

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    ABSTRACT: Introduction: Modes of cognitive vulnerability were evaluated in outpatients of psychological services centers with diagnoses of mental disorders. Objective: To establish components of cognitive vulnerability in different mental disorders. Method: The participants were 490 users of psychological services centers from twelve universities in Colombia. To identify the presence or absence of mental disorders, they completed the MINI International Neuropsychiatric Interview.The Young Schemes Questionnaire, the Core Beliefs Questionnaire for Personality Disorders, the Inventory of Automatic Thoughts, and the Coping Strategies Questionnaire were also applied. To establish distinctive characteristics among actual major depression, generalized anxiety disorder, panic disorder, social anxiety, and non-alcoholic substance abuse, a logistic regression analysis was conducted. Results: The results showed cognitive distinctive vulnerability profiles, according to the disorder. Conclusion: The hypothesis of cognitive specificity for the different mental disorders is confirmed.RESUMEN: Introducción: Se evaluaron los modos de vulnerabilidad cognitiva en usuarios de consulta externa en psicología, diagnosticados con trastornos mentales. Objetivo: Establecer componentes de vulnerabilidad cognitiva en diferentes trastornos mentales. Método: Participaron 490 usuarios de servicios psicológicos de doce universidades de Colombia. Se aplicó la Entrevista Neuropsiquiátrica Internacional para identificar la presencia o no de trastornos mentales; igualmente, se aplicaron el Cuestionario de Esquemas de Young, el Cuestionario de Creencias Centrales de Trastornos de la Personalidad, el Inventario de Pensamientos Automáticos y el Cuestionario de Estrategias de Afrontamiento. Se realizaron análisis de regresión logística para establecer características distintivas en los trastornos de depresión mayor actual, ansiedad generalizada, angustia, ansiedad social y abuso de sustancias no alcohólicas. Resultados: Se reportaron perfiles cognitivos de vulnerabilidad diferenciados de acuerdo con el trastorno. Conclusión: Se confirma la hipótesis de especificidad cognitiva para los diferentes trastornos mentales

    Factores de riesgo psicosociales y ambientales asociados a trastornos mentales

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    In Colombia, there are few studies on the association of psychosocial and environmental factors with the most prevalent mental disorders; such studies are important due to the context of violence, social insecurity, and job and economic instability in the country. The objective of this study was to identify the psychosocial and environmental risk factors for mental disorders, in users of psychological services in Colombia. The Mini International Neuropsychiatric Interview and a Questionnaire to evaluate the Axis-IV of the DSM-IV-TR were applied to 490 participants. The analysis comprised descriptive statistics and risk factors. As risk factors for depression, there were identified housing problems, access to health care services, problems related to the primary group, economics, problems of the social environment, and labor. For generalized anxiety, there were identified economic and education issues. For panic disorders, the risk factors were related to social environment, and for social phobia, the risk factors were problems in education, work and social environment.En Colombia, son escasos los estudios sobre la asociación de los factores psicosociales y medioambientales con trastornos mentales de mayor prevalencia; tales estudios son necesarios debido al contexto de violencia, inseguridad social e inestabilidad laboral y económica del país. El objetivo de este estudio fue identificar los factores de riesgo psicosociales y ambientales de los trastornos mentales, en los usuarios de servicios de psicología de Colombia. Para ello, se aplicaron el MiniInternational Neuropsychiatric Interview y un cuestionario de evaluación del Eje IV del DSM-IV-TR, a 490 participantes. Se utilizaron análisis descriptivos y de factores de riesgo. Como factor de riesgo para la depresión, se identificaron los problemas de vivienda, acceso a los servicios de asistencia sanitaria, los relativos al grupo primario, los económicos, del ambiente social y los problemas laborales. Para la ansiedad generalizada se identificaron los problemas económicos y los relativos a la enseñanza. Para los trastornos de pánico, fueron relevantes los problemas relacionados con el ambiente social, y para la fobia social, los problemas de enseñanza, los laborales y el ambiente social

    The Hemorrhagic Coli Pilus (HCP) of Escherichia coli O157:H7 Is an Inducer of Proinflammatory Cytokine Secretion in Intestinal Epithelial Cells

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    Enterohemorrhagic Escherichia coli (EHEC) O157:H7, the causative agent of hemorrhagic colitis and the hemolytic uremic syndrome (HUS), produces long bundles of type IV pili (TFP) called hemorrhagic coli pili (HCP). HCP are capable of mediating several phenomena associated with pathogenicity: i) adherence to human and bovine epithelial cells; ii) invasion of epithelial cells; iii) hemagglutination of rabbit erythrocytes; iv) biofilm formation; v) twitching motility; and vi) specific binding to laminin and fibronectin. HCP are composed of a 19 kDa pilin subunit (HcpA) encoded by the hcpA chromosomal gene (called prepilin peptidase-dependent gene [ppdD] in E. coli K-12).In this study we investigated the potential role of HCP of E. coli O157:H7 strain EDL933 in activating the release of pro- and anti-inflammatory cytokines from a variety of host epithelial cells. We found that purified HCP and a recombinant HcpA protein induced significant release of IL-8 and TNF-alpha, from cultured polarized intestinal cells (T84 and HT-29 cells) and non-intestinal HeLa cells. Levels of proinflammatory IL-8 and TNF-alpha, but not IL-2, IL6, or IL-10 cytokines, were increased in the presence of HCP and recombinant HcpA after 6 h of incubation with >or=50 ng/ml of protein, suggesting that stimulation of IL-8 and TNF-alpha are dose and time-dependent. In addition, we also demonstrated that flagella are potent inducers of cytokine production. Furthermore, MAPK activation kinetics studies showed that EHEC induces p38 phosphorylation under HCP-producing conditions, and ERK1/2 and JNK activation was detectable after 3 h of EHEC infection. HT-29 cells were stimulated with epidermal growth factor stimulation of HT-29 cells for 30 min leading to activation of three MAPKs.The HcpA pilin monomer of the HCP produced by EHEC O157:H7 is a potent inducer of IL-8 and TNF-alpha release, an event which could play a significant role in the pathogenesis of hemorrhagic colitis caused by this pathogen

    Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

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    Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA
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