Age and growth of the highly exploited narrownose smooth-hound (Mustelus schmitti) (Pisces: Elasmobranchii)

The narrownose smoothhound (Mustelus schmitti) is the most exploited elasmobranch of Argentina, Brazil, and Uruguay and is considered endangered (IUCN Red List of Threatened Species). Providing information on age and growth can improve efforts for conservation of this species. Therefore, our objective was to provide accurate estimates of the age structure and growth parameters for narrownose smooth-hound from Anegada Bay, an important shark nursery area in Argentina. In vertebrae of narrownose smooth-hound, we observed a pattern of alternating opaque and translucent bands and a yearly periodicity in the deposition of this pattern. Ages determined from vertebral band counts ranged from 0 to 11 years. Calculated longevity and total natural mortality rates were 20.87 years and 0.19/year for females and 12.24 years and 0.26/year for males, respectively. This species reached a size of approximately 400 mm in total length in the initial year of growth, and the age at first maturity was 7.61 years for females and 6.79 years for males. The slow growth and late age at maturity of the narrownose smoothhound indicate a need for additional conservation measures to rebuild the population and achieve a sustainable fishery in the 3 countries in which it is distributed.Fil: Molina, Juan Manuel. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Blasina, Gabriela Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

Caracterizacion de la quimiotaxis de la rizobacteria Pseudomonas chlororaphis PCL1606

Polonio A, Escaño C, Codina JC, de Vicente A, Cazorla FM. 2014. Caracterización de la quimiotaxis de la rizobacteria PCl1606. XVII Congreso de la Sociedad Española de Fitopatología. Libro de resumenes, pp. 258.La rizobacteria Pseudomonas chlororaphis PCL1606 es una bacteria antagonista que produce el antibiótico antifúngico 2-hexil-5-propilresorcinol (HPR). Además, es capaz de colonizar las raíces de aguacate y las hifas del hongo Rosellinia necatrix, actividades responsables de su fenotipo antagonista. Para profundizar en el mecanismo de colonización de raíces e hifas, así como en las interacciones multitróficas que se establecen en la rizosfera durante el biocontrol de Pseudomonas chlororaphis PCL1606, se caracterizó su quimiotaxis. Para ello se puso a punto una técnica en placa y otra en capilares. Los resultados obtenidos muestran que Pseudomonas chlororaphis PCL1606 tiene quimiotaxis positiva hacia varios compuestos descritos comúnmente en la rizosfera a concentraciones no muy elevadas. Algunos de estos compuestos, a concentraciones superiores, llegaron a ser quimiorrepelentes. Por otro lado, la técnica de quimiotaxis en capilares resultó ser más sensible, permitió la cuantificación de la actividad quimiotáctica y reveló quimiotaxis positiva hacia los exudados de Rosellinia y aguacate a dos concentraciones diferentes. Estos resultados sugieren que el mecanismo quimiotáctico posee un efecto positivo en la colonización activa de raíces e hifas por parte de Pseudomonas chlororaphisPCL1606. Este trabajo ha sido financiado con el apoyo de una subvención del proyecyo del Plan Nacional de I+D+I del Ministerio de Economía y Competitividad (AGL2011-30354-CO2-01).Este trabajo ha sido financiado con el apoyo de una subvención del proyecyo del Plan Nacional de I+D+I del Ministerio de Economía y Competitividad (AGL2011-30354-CO2-01).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. - See more at: http://riuma.uma.es/xmlui/handle/10630/5449/submit/69126576403c093566461c417a1d35417e266852.continue#sthash.LIAUJjTD.dpu

Life in the surf-zone: Variations of faunal assemblage structure in temperate sandy beaches of the Southwestern Atlantic coast

This study explores the changes of biological descriptors -richness, diversity and abundance-of faunal surf-zone assemblage along a temperate coastal fringe. Three mesotidal sandy beaches with different morphodynamic states, adjacent to an estuarine zone, were seasonally sampled during a year. Zooplankton, zoobenthos and fish samples were taken in the surf-zone and a set of potential explanatory environmental variables were measured and/or quantified. Generalized linear models (GLM) were employed to compare environmental and biological variables between beaches and seasons. Beaches varied from tide-dominated flat to tide-modified reflective to intermediate. The assemblage included 108 taxa, of which few were numerically dominant. Richness of each biological group was similar along the shore and higher values of α-diversity were associated with minimum values of total abundance. β-diversity was mainly a consequence of species turnover, mostly due to changes in zoobenthic and zooplanktonic taxa. Results of GLM test showed that seasons and beaches have an interdependent effect on the abundance of the surf-zone assemblage. All biological groups showed marked seasonal variability in its occurrence, possibly associated with environmental variables, such as temperature and photosynthetic pigment concentrations. Zooplankton and fish groups reached maximum abundance, during autumn and spring respectively, in tide-modified beaches where the surf-zone was well developed and waves reached higher heights. Zoobenthic abundance peaked in beaches with narrower surf-zone and lower wave energy, during autumn, winter and spring, which could be advantageous for those taxa that escape from predators by burying or for species that actively swim near the seafloor. The copepod Acartia tonsa, the clupeidae fish Ramnogaster arcuata and the mysids Arthromysis magellanica and Neomysis americana all typical species of the neighboring estuary, were the main responsibles for these distribution patterns. The connection of the surf-zone with the adjacent estuarine area is also evident by its role in enriching the dissolved organic matter of surf-waters.Fil: Fiori, Sandra Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Martinez, Ana María. 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 Nacional del Sur. Departamento de Química; ArgentinaFil: Carcedo, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Blasina, Gabriela Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Garzon Cardona, John Edison. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Moyano, Jessica Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Química; ArgentinaFil: Menendez, Maria Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

La rizobacteria Pseudomonas alcaligenes AVO110 induce la expresión de genes relacionados con formación de biofilms en respuesta a exudados de Rosellinia necatrix

La rizobacteria Pseudomonas alcaligenes AVO110 muestra antagonismo frente al hongo fitopatógeno Rosellinia necatrix. Esta cepa coloniza eficazmente las hifas de R. necatrix y es capaz de alimentarse de sus exudados. Recientemente, hemos publicado la secuencia completa del genoma de P. alcaligenes AVO110. La filogenia de todos los genomas de P. alcaligenes disponibles separa los aislados ambientales, procedentes de agua, junto a la cepa AVO110, de los obtenidos de infecciones de sangre humana y de tejidos de ostras, que agrupan con Pseudomonas otitidis. Análisis del core y del pangenoma de P. alcaligenes han revelado que las cepas de esta especie codifican conjuntos de genes altamente heterogéneos, y que el genoma de AVO110 codifica la región variable más grande y exclusiva de todos ellos (aproximadamente 1,6 Mb y 1795 genes). Los genes exclusivos de AVO110 incluyen un amplio repertorio de genes relacionados con la formación de biopelículas (biofilms), de entre los cuales destacan aquellos modulados transcripcionalmente por exudados de R. necatrix. Uno de estos genes (cmpA) codifica una proteína con dominios GGDEF/EAL específica de cepas de Pseudomonas spp. aisladas de la rizosfera de diversas plantas, de suelo y de agua. También hemos demostrado que CmpA tiene un papel en la formación de biopelículas y que la integridad de su dominio EAL está involucrada en esta función. Este trabajo contribuye a una mejor comprensión del estilo de vida y de la adaptación a nichos específicos de P. alcaligenes, incluido el comportamiento micofágico de la cepa AVO110.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Biology of Myliobatis goodei (Springer, 1939) a widely distributed eagle ray caught in northern Patagonia

Chondrichthyans play an important role in structuring marine communities. Myliobatis goodie is an eagle ray reported from South Carolina in USA (35°N) to Santa Cuz, Argentina (44°S), however little is known about this species, which is considered Data Deficient by the IUCN. In order to create adequate management strategies for this species, biological information is sorely needed. The objective of this study was to describe the biology of the population of M. goodei and its relationships with season, sex and the geographic features of Anegada Bay, Argentina (from 39.96°S to 40.60°S and from 62.10°W to 62.46°W) during 2008. Specifically, the population structure of M. goodie was studied by sex, seasons and sites, its food habits by seasons and sites, and the reproductive biology by seasons and sex. The results show that M. goodei exhibits seasonal migrations. Young-of-the-year remain in the bay all year long, while adults enter during spring and summer. Juveniles in spring are likely to become first-time mating individuals that migrate into open sea at the end of summer. These individuals would return to give birth for the first time and mate for the second time during the next year at summer. Anegada Bay would then be a mating and nursery area for the species. M. goodei behave as a generalist feeder with a uniform diet composed mainly of bivalves. Seasonal differences in the diet found arise from differences in prey diversity between summer and spring. Spatial differences, however, arise from the different abundances of caprelids and bivalves. Trophic level was 3.2 and it constitutes the first reference for this species, characterizing it as a secondary consumer.Fil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Cient__itilde__ficas y T__etilde__cnicas; Argentina. Universidad Nacional del Sur; ArgentinaFil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Cient__itilde__ficas y T__etilde__cnicas; Argentina. Universidad Nacional del Sur; Argentin

Trophic ecology of Mustelus schmitti (Springer, 1939) in a nursery area of northern Patagonia

Mustelus schmitti is an endangered endemic shark of the southwest Atlantic, and an important economical resource in Argentina, Brazil and Uruguay. The objective of this study was to describe the trophic ecology of M. schmitti in Anegada Bay, its feeding strategy and diet composition, along with the possible dietary shifts, due to season, sex, ontogeny and the different geographical features of the bay. Our results show that M. schmitti is a carnivorous opportunistic predator, feeding on a variety of benthic invertebrates. The diet presented seasonal and ontogenetic variations, while no differences in diet composition were observed between sexes or the different sampling sites. This species behave as a generalize feeder, with a wide trophic spectrum and a diverse diet. © 2011 Elsevier B.V.Fil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentin

The artisanal fishery of Cynoscion guatucupa in Argentina: Exploring the possible causes of the collapse in Bahía Blanca estuary

Cynoscion guatucupa Cuvier 1829 is a migratory pelagic fish species, which has a wide geographical distribution. It is the most important fishing resource for local communities in Bahía Blanca estuary and has been captured by artisanal fishermen since the 1900s. The industrial fleet has been fishing this species in the coastal area of Buenos Aires province since the 1950s, and, since 1970, landings have increased sharply. Between 2000 and 2004, the artisanal fishery in the estuarine waters of Bahía Blanca collapsed. Variations in total landings of the artisanal fleet might have arisen from the environmental variables within the estuary, fishing activity in the surrounding sea region, local pressure within the estuary and/or several other variables. Our results suggest that neither oceanographic parameters nor local pressure seem to have influenced the artisanal fishery of C. guatucupa in the estuarine region. Instead, this fishery seems to have been partially influenced by the increasing fishing pressure exerted by the industrial fishing fleet operating in open waters around the estuary. This study emphasizes the need to take into account fisheries data from both the estuarine environment and the surrounding sea region, particularly when designing management plans for the sustainable use of migrating fish resources.Fil: Lopez Cazorla, Andrea Cecilia. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Ruarte, Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; Argentin

Ecology and biology of the fish assemblages

In the chapter we summarize the current state of knowledge regarding the assemblages of fish species inhabiting the waters of Bahía Blanca Estuary. We begin by exploring the diversity of habitats and resources available for fish species, and then describe the different guilds of fish present in the estuary, based on historical data collections and current biological surveys. A list of the species of each guild and a brief description of the key biological features, such as habitat, distribution, reproduction and feeding habits of most relevant species is given. Spatial and temporal fluctuations in species composition within the estuary are described. We conclude this chapter with a section dedicated to the challenges that fish species are subject to in the Anthropocene and the temporal fluctuations in species composition within the estuary in the last 30 years. Chapter contents a test-box deals the artisanal fishery that operates within the estuary, and that has been subjected to various degrees of pressure from the industrial fleet operating in open waters outside the boundaries of the estuary. This chapter highlights the astounding abundance and diversity of fish living in this estuary, and the pressing need to ensure their conservation.Fil: Molina, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Blasina, Gabriela Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Lopez Cazorla, Andrea Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentin