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1.
Conserv Biol ; 34(1): 103-112, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31257646

RESUMEN

More than half of the world's 18 penguin species are declining. We, the Steering Committee of the International Union for Conservation of Nature Species Survival Commission Penguin Specialist Group, determined that the penguin species in most critical need of conservation action are African penguin (Spheniscus demersus), Galápagos penguin (Spheniscus mendiculus), and Yellow-eyed penguin (Megadyptes antipodes). Due to small or rapidly declining populations, these species require immediate scientific collaboration and policy intervention. We also used a pairwise-ranking approach to prioritize research and conservation needs for all penguins. Among the 12 cross-taxa research areas we identified, we ranked quantifying population trends, estimating demographic rates, forecasting environmental patterns of change, and improving the knowledge of fisheries interactions as the highest priorities. The highest ranked conservation needs were to enhance marine spatial planning, improve stakeholder engagement, and develop disaster-management and species-specific action plans. We concurred that, to improve the translation of science into effective conservation for penguins, the scientific community and funding bodies must recognize the importance of and support long-term research; research on and conservation of penguins must expand its focus to include the nonbreeding season and juvenile stage; marine reserves must be designed at ecologically appropriate spatial and temporal scales; and communication between scientists and decision makers must be improved with the help of individual scientists and interdisciplinary working groups.


Aplicación de Ciencia en las Necesidades de Conservación Urgentes para los Pingüinos. Resumen Más de la mitad de las 18 especies de pingüinos del mundo están disminuyendo. Nosotros, el Comité Directivo de la Unión Internacional para la Conservación de la Naturaleza, Grupo de Especialistas en Pingüinos, determinamos que las especies de pingüinos con necesidades críticas de conservación son el pingüino africano (Spheniscus demersus), el pingüino de las Galápagos (Spheniscus mendiculus) y el pingüino de ojos amarillos (Megadyptes antipodes). Debido a que sus poblaciones son pequeñas o están declinando rápidamente, estos pingüinos requieren colaboración científica e intervención política inmediatas. También utilizamos un método de clasificación por pares para priorizar las necesidades de investigación y conservación para todas las especies de pingüinos. Entre las 12 áreas de investigación que identificamos, las más prioritarias fueron: cuantificación de las tendencias poblacionales, estimación de las tasas demográficas, predicción de las patrones de cambio ambiental y mejora del conocimiento de las interacciones con pesquerías. Las mayores necesidades de conservación fueron: optimizar la planificación marina espacial, mejorar la colaboración de las partes interesadas y desarrollar planes de manejo de desastres y de acción para cada especie. Coincidimos en que, para mejorar la traducción de la ciencia en la conservación efectiva de los pingüinos, la comunidad científica y los organismos financiadores deben reconocer la importancia de la investigación a largo plazo y apoyarla; la investigación sobre pingüinos y su conservación debe expandir su enfoque para incluir la época no reproductiva y la etapa juvenil; las reservas marinas deben ser diseñadas a escalas espaciotemporales ecológicamente apropiadas; y la comunicación entre científicos y tomadores de decisiones debe mejorar con la ayuda de científicos individuales y grupos de trabajo interdisciplinario.


Asunto(s)
Spheniscidae , Animales , Conservación de los Recursos Naturales , Explotaciones Pesqueras , Especificidad de la Especie
2.
Sci Rep ; 8(1): 17481, 2018 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-30504851

RESUMEN

Since at least the middle-Miocene, the Antarctic Polar Front (APF) and the Subtropical Front (STF) appear to have been the main drivers of diversification of marine biota in the Southern Ocean. However, highly migratory marine birds and mammals challenge this paradigm and the importance of oceanographic barriers. Eudyptes penguins range from the Antarctic Peninsula to subantarctic islands and some of the southernmost subtropical islands. Because of recent diversification, the number of species remains uncertain. Here we analyze two mtDNA (HVRI, COI) and two nuclear (ODC, AK1) markers from 13 locations of five putative Eudyptes species: rockhopper (E. filholi, E. chrysocome, and E. moseleyi), macaroni (E. chrysolophus) and royal penguins (E. schlegeli). Our results show a strong phylogeographic structure among rockhopper penguins from South America, subantarctic and subtropical islands supporting the recognition of three separated species of rockhopper penguins. Although genetic divergence was neither observed among macaroni penguins from the Antarctic Peninsula and sub-Antarctic islands nor between macaroni and royal penguins, population genetic analyses revealed population genetic structure in both cases. We suggest that the APF and STF can act as barriers for these species. While the geographic distance between colonies might play a role, their impact/incidence on gene flow may vary between species and colonies.

3.
J Thromb Haemost ; 5(8): 1774-81, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17488347

RESUMEN

BACKGROUND: The dietary flavonoid apigenin (Api) has been demonstrated to exert multiple beneficial effects upon the vascular endothelium. The aim of this study was to examine whether Ca(2+)-activated K(+) channels (K(Ca)) are involved in endothelial nitric oxide (NO) production and antiangiogenic effects. METHODS: Endothelial NO generation was monitored using a cyclic guanosine monophosphate radioimmunoassay. K(Ca) activity and changes of the intracellular Ca(2+) concentration [Ca(2+)](i) were analyzed using the fluorescent dyes bis-barbituric acid oxonol, potassium-binding benzofuran isophthalate, and fluo-3. The endothelial angiogenic parameters measured were cell proliferation, [(3)H]-thymidine incorporation, and cell migration (scratch assay). Akt phosphorylation was examined using immunohistochemistry. RESULTS: Api caused a concentration-dependent increase in cyclic guanosine monophosphate levels, with a maximum effect at a concentration of 1 mum. Api-induced hyperpolarization was blocked by the small and large conductance K(Ca) inhibitors apamin and iberiotoxin, respectively. Furthermore, apamin and iberiotoxin blocked the late, long-lasting plateau phase of the Api-induced biphasic increase of [Ca(2+)](i). Inhibition of Ca(2+) signaling and the K(Ca) blockade both blocked NO production. Prevention of all three (NO, Ca(2+), and K(Ca) signaling) reversed the antiangiogenic effects of Api under both basal and basic fibroblast growth factor-induced culture conditions. Basic fibroblast growth factor-induced Akt phosphorylation was also reduced by Api. CONCLUSIONS: Based on our experimental results we propose the following signaling cascade for the effects of Api on endothelial cell signaling. Api activates small and large conductance K(Ca), leading to a hyperpolarization that is followed by a Ca(2+) influx. The increase of [Ca(2+)](i) is responsible for an increased NO production that mediates the antiangiogenic effects of Api via Akt dephosphorylation.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Apigenina/metabolismo , Calcio/metabolismo , Óxido Nítrico/metabolismo , Canales de Potasio/metabolismo , Movimiento Celular , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Humanos , Modelos Biológicos , Fosforilación , Canales de Potasio/química , Radioinmunoensayo , Transducción de Señal , Factores de Tiempo , Venas Umbilicales/metabolismo
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