Manioc : Portail | resultats 1 - 20 pour la recherche: Hanage, William P.

Éditeur(s) : HAL CCSD Landes Bioscience
Résumé : International audience
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
Autophagy

hal-00735751
https://hal.archives-ouvertes.fr/hal-00735751
PUBMED : 22966490

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Hampa afro-cubana : Los negros brujos : Apuntes para un estudio de etnología criminal
Auteur(s) : Ortiz, Fernando (1881-1969)
Auteurs secondaires : Lombroso, Cesare (1835-1909)
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The West Indies
Auteur(s) : Eves, Charles Washington Augero (1838-1899)
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Phylogenetic diversity of Amazonian tree communities
Auteur(s) : Honorio Coronado, Eurídice N. Dexter, Kyle G. Pennington, R. Toby Chave, Jérôme Lewis, Simon L. Alexiades, Miguel N. Alvarez, Esteban Alves de Oliveira, Atila
Auteurs secondaires : School of Geography [Leeds] ; University of Leeds School of Geosciences [Edinburgh] ; University of Edinburgh Royal Botanic Garden Edinburgh Evolution et diversité biologique (EDB) ; Université Paul Sabatier - Toulouse 3 (UPS) - Ecole Nationale Supérieure Agronomique de Toulouse - Centre National de la Recherche Scientifique (CNRS) University of Kent [Canterbury] Instituto Nacional de Pesquisas da Amazônia (INPA) ; Instituto Nacional de Pesquisas da Amazônia Projeto TEAM-Manaus ; Instituto Nacional de Pesquisas da Amazônia Universidad Autonoma Gabriel René Moreno (UAGRM)

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Aim To examine variation in the phylogenetic diversity (PD) of tree communities across geographical and environmental gradients in Amazonia.Location Two hundred and eighty-three c.1ha forest inventory plots from across Amazonia.Methods We evaluated PD as the total phylogenetic branch length across species in each plot (PDss), the mean pairwise phylogenetic distance between species (MPD), the mean nearest taxon distance (MNTD) and their equivalents standardized for species richness (ses.PDss, ses.MPD, ses.MNTD). We compared PD of tree communities growing (1) on substrates of varying geological age; and (2) in environments with varying ecophysiological barriers to growth and survival.Results PDss is strongly positively correlated with species richness (SR), whereas MNTD has a negative correlation. Communities on geologically young- and intermediate-aged substrates (western and central Amazonia respectively) have the highest SR, and therefore the highest PDss and the lowest MNTD. We find that the youngest and oldest substrates (the latter on the Brazilian and Guiana Shields) have the highest ses.PDss and ses.MNTD. MPD and ses.MPD are strongly correlated with how evenly taxa are distributed among the three principal angiosperm clades and are both highest in western Amazonia. Meanwhile, seasonally dry tropical forest (SDTF) and forests on white sands have low PD, as evaluated by any metric.Main conclusions High ses.PDss and ses.MNTD reflect greater lineage diversity in communities. We suggest that high ses.PDss and ses.MNTD in western Amazonia results from its favourable, easy-to-colonize environment, whereas high values in the Brazilian and Guianan Shields may be due to accumulation of lineages over a longer period of time. White-sand forests and SDTF are dominated by close relatives from fewer lineages, perhaps reflecting ecophysiological barriers that are difficult to surmount evolutionarily. Because MPD and ses.MPD do not reflect lineage diversity per se, we suggest that PDss, ses.PDss and ses.MNTD may be the most useful diversity metrics for setting large-scale conservation priorities.
ISSN: 1366-9516

hal-01557462
https://hal.univ-lorraine.fr/hal-01557462
DOI : 10.1111/ddi.12357

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Antigua and the Antiguans: a full account of the colony and its inhabitants from the time of the Caribs to the present day, interspersed with anecdotes and legends : also, an impartial view of slavery and the free labour systems, the statistics of the island, and biographical notices of the principal families, Volume 2
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A treatise of the diseases most frequent in the West-Indies, and herein more particularly of those which occur in Barbadoes
Auteur(s) : Towne, Richard (1690-17..)
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Rapport sur les questions coloniales adressé à M. le duc de Broglie,... à la suite d'un voyage fait aux Antilles et aux Guyanes pendant les années 1838 et 1839. Tome II, Documents et pièces justificatives. Deuxième partie, Etude de l'émancipation dans les colonies anglaises depuis l'année 1833 jusqu'au 3 décembre 1842
Auteur(s) : Lechevalier Saint-André, Jules (1806-1862)
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