Influence of the thermocline on the vertical migration of medusae during a 48 h sampling period

The vertical distribution and migratory movements of epiplanktonlc medusae were studied at an oceanic station off northern Namibia (18°00’S /10°30’E). Samples were collected from five separate depth strata (200–100 m, 100–60 m, 60–40 m, 40–20 m, and 20–0 m) using a multiple opening and closing RMT 1 x 6 net over a 48–h period. The area was characterized by mixing of the Angola Current surface waters with the northernmost subsurface waters of the Benguela Current. During the sampling period there was a continuous flow of water from Angola, giving rise to a strong thermocline between 20 and 40 m depth. A total of 17 species of medusae were captured, of which Aglaura hemistoma, Liriope tetraphylla, and Solmundella bitentaculata were the most abundant. Both the number of species and the number of individuals were higher on the second than on the first day of sampling, chiefly in the 20–0 stratum. Differences in abundance appeared to be related to the patch size of each species. The depth diistributlon of the medusae population was characterized by the existence of two assemblages, one associated with each current, and by the presence of the thermocline, which acted as a boundary between the two water masses and did not facilitate migratory movements of the most abundant species. The non-migratory distribution pattern of most of the species was attributable to the high concentration of potential prey items and to the absence of predators in the layer above the thermocline throughout the sampling period

Etude de la variabilité d'un agent pathogène, Xanthomonas campestris pv manihotis, par l'analyse factorielle multiple

International audienc

Mitochondrial and ribosomal biogenesis are new hallmarks of stemness, oncometabolism and biomass accumulation in cancer : mito-stemness and ribo-stemness features

Using proteomics analysis, we previously compared MCF7 breast cancer cells grown as 3D tumor spheres, with the same cell line grown as monolayers. Our results indicated that during 3D anchorage‐independent growth, the cellular machinery associated with i) mitochondrial biogenesis and ii) ribosomal biogenesis, were both significantly increased. Here, for simplicity, we refer to these two new oncogenic hallmarks as “mito‐stemness” and “ribo‐stemness” features. We have now applied this same type of strategy to begin to understand how fibroblasts and MCF7 breast cancer cells change their molecular phenotype, when they are co‐cultured together. We have previously shown that MCF7‐fibroblast co‐cultures are a valuable model of resistance to apoptosis induced by hormonal therapies, such as Tamoxifen and Fulvestrant. Here, we directly show that these mixed co‐cultures demonstrate the induction of mito‐stemness and ribo‐stemness features, likely reflecting a mechanism for cancer cells to increase their capacity for accumulating biomass. In accordance with the onset of a stem‐like phenotype, KRT19 (keratin 19) was induced by ~6‐fold during co‐culture. KRT19 is a well‐established epithelial CSC marker that is used clinically to identify metastatic breast cancer cells in sentinel lymph node biopsies. The potential molecular therapeutic targets that we identified by label‐free proteomics of MCF7‐fibroblast co‐cultures were then independently validated using a bioinformatics approach. More specifically, we employed publically‐available transcriptional profiling data derived from primary tumor samples from breast cancer patients, which were previously subjected to laser‐capture micro‐dissection, to physically separate breast cancer cells from adjacent tumor stroma. This allowed us to directly validate that the proteins up‐regulated in this co‐culture model were also transcriptionally elevated in patient‐derived breast cancer cells in vivo. This powerful approach for target identification and translational validation, including the use of patient outcome data, can now be applied to other tumor types as well, to validate new therapeutic targets that are more clinically relevant, for patient benefit. Moreover, we discuss the therapeutic implications of these findings for new drug development, drug repurposing and Tamoxifen‐resistance, to effectively target mito‐stemness and ribo‐stemness features in breast cancer patients. We also discuss the broad implications of this “organelle biogenesis” approach to cancer therapy

Matrix composition and patch edges influence plant-herbivore interactions in marine landscapes

38 páginas, 4 figuras, 3 tablas.1. The functioning of ecosystems can be strongly driven by landscape attributes. Despite its importance, however, our understanding of how landscape influences ecosystem function derives mostly from species richness and abundance patterns, with few studies assessing how these relate to actual functional rates. 2. We examined the influence of landscape attributes on the rates of herbivory in seagrass meadows, where herbivory has been identified as a key process structuring these relatively simple systems. The study was conducted in three representative Posidonia oceanica meadows. The principal herbivores in these meadows are the fish Sarpa salpa and the sea urchin Paracentrotus lividus, and we hypothesised that differences in their interaction with landscape attributes would significantly influence herbivory rates. 3. We measured herbivore abundance, herbivory rates, primary production and plant quality (C:N) in seagrass patches embedded either in rock or in sand (matrix attribute), in patches either near or far from a rocky reef (distance attribute) and at the edges and interior of meadows. 4. Our results show that matrix and meadow edges significantly affected the actual levels of herbivory. Herbivory rates were higher in seagrass patches embedded in a rocky matrix compared to those on sand, and herbivory at the centre of seagrass meadows was higher than at the edges. In contrast, patch distance to rocky reefs did not affect herbivory. Neither herbivore abundance nor food quality explained the patterns across different landscape attributes. This suggests that variation in herbivory across the landscape may be related much more to behavioural differences between species in their evaluation of risk, movement, and food preference in relation to the landscape structure. 5. Our results indicate that richness and abundance patterns may mask critical interactions between landscape attributes and species responses, which result in considerable heterogeneity in the way key functional processes like herbivory are distributed across the ecosystem mosaic.The Spanish Ministry of Science and Innovation funded this research (projects CTM2010-22273-C02-01 and 02). The Spanish Ministry of Education supported JP (scholarship AP2008-01601) and the Spanish National Research Council supported AG (scholarship JAEPre_08_00466).Peer reviewe

Mitochondrial fission as a driver of stemness in tumor cells : mDIVI1 inhibits mitochondrial function, cell migration and cancer stem cell (CSC) signalling

Mitochondria are dynamic organelles frequently undergoing fission and fusion events to maintain their integrity, bioenergetics and spatial distribution, which is fundamental to the processes of cell survival. Disruption in mitochondrial dynamics plays a role in cancer. Therefore, proteins involved in regulating mitochondrial dynamics are potential targets for treatment. mDIVI1 is an inhibitor of the mitochondrial fission protein DRP1, which induces i) mitochondrial oxidative stress and ii) effectively reduces mitochondrial metabolism. We show here that mDIVI1 is able to inhibit 3D tumorsphere forming capacity, cell migration and stemness-related signalling in breast cancer cells, indicating that mDIVI1 can potentially be used for the therapeutic elimination of cancer stem cells (CSCs)

Matrix composition and patch edges influence plant-herbivore interactions in marine landscapes

38 páginas, 4 figuras, 3 tablas.1. The functioning of ecosystems can be strongly driven by landscape attributes. Despite its importance, however, our understanding of how landscape influences ecosystem function derives mostly from species richness and abundance patterns, with few studies assessing how these relate to actual functional rates. 2. We examined the influence of landscape attributes on the rates of herbivory in seagrass meadows, where herbivory has been identified as a key process structuring these relatively simple systems. The study was conducted in three representative Posidonia oceanica meadows. The principal herbivores in these meadows are the fish Sarpa salpa and the sea urchin Paracentrotus lividus, and we hypothesised that differences in their interaction with landscape attributes would significantly influence herbivory rates. 3. We measured herbivore abundance, herbivory rates, primary production and plant quality (C:N) in seagrass patches embedded either in rock or in sand (matrix attribute), in patches either near or far from a rocky reef (distance attribute) and at the edges and interior of meadows. 4. Our results show that matrix and meadow edges significantly affected the actual levels of herbivory. Herbivory rates were higher in seagrass patches embedded in a rocky matrix compared to those on sand, and herbivory at the centre of seagrass meadows was higher than at the edges. In contrast, patch distance to rocky reefs did not affect herbivory. Neither herbivore abundance nor food quality explained the patterns across different landscape attributes. This suggests that variation in herbivory across the landscape may be related much more to behavioural differences between species in their evaluation of risk, movement, and food preference in relation to the landscape structure. 5. Our results indicate that richness and abundance patterns may mask critical interactions between landscape attributes and species responses, which result in considerable heterogeneity in the way key functional processes like herbivory are distributed across the ecosystem mosaic.The Spanish Ministry of Science and Innovation funded this research (projects CTM2010-22273-C02-01 and 02). The Spanish Ministry of Education supported JP (scholarship AP2008-01601) and the Spanish National Research Council supported AG (scholarship JAEPre_08_00466).Peer reviewe

Penicillium aureocephalum Munt.-Cvetk., Hoyo et Gómez-Bolea, un interessant ascomicet anamòrfic amb aspecte de mixomicet : distribució, ecologia i fenologia

Cinc anys després de la descripció de Penicillium aureocephalum per Muntañola-Cvetkovic, Hoyo i GórnezBolea, els autors del present treball han anat afegint Inés dades de camp a les ja existents, que comencen a subministrar una imatge més viva d'aquest curiós anamorf saprotrófic dins de les comunitats naturals on esporula. El present treball és un resum d'aquestes dades corológiques, ecológiques i fenológiques, acompanyat de comentaris. La principal conclu sió és que I'espécie se' ns presenta com un fong termófil que colonit za preferentm ent fulles caigudes de surera (Quercus suber), que han mort a l' arbre per la calor produída per incendis, pero que també pot créixer, menys sovint, sobre altres substrats, com ara fulles o fruits de Cistus salviifolius, C. ladanifer, Quercus coccifera, etc. que han estat descarre gats per les plantes com a resposta a un fort estrés hídric. El treball inclou un mapa de la distribuci ó de I'espécie en el Pare Natural del Cap de Creus, fins ara I' área óptima de creixement, i un altre mapa amb la distribució coneguda actualment en els Paisos Catalans, on apareix provisionahnent endémica. S'ofereix un estudi macrofotográfic de l'especie, útil per ajudar els mic ólegs a trobar noves localitat s d'aquest curiosa especie d'anamorf, tan diferent de les més conegudes de Penicillium , ja que té aspect e de mixomic et, que es comporta COIll a term ófila i saprotrófica sobre fulles riques en nutrients.Five years after the description of Penicillium aureocephalum by Muntañola-C vetkovic, Hoyo and G ómez-Bolea, an increasing wealth of field data has been gathered by the authors, which provide a vivid image of the anamorph of this curious saprotrophic species. Chorological, ecological and phenological data are here summarized and discussed. The species appears to be thermophilou s, preferentially colonizing fallen leaves of cork trees (Quercus suber) killed by wildfires, but also growing sometimes on other substrata, such as dead leaves of Cistus salviifolius,C. ladanifer, Quercus coccifera, etc. which may have dropped as a response to severe water stress. A distribution map of the species in the Natural Park of Cap de Creus, which apparently is its natural habitat and another nowith showing the currently known distribution in the Catalan Countries, are given. A macrophotographic survey ofthe species is also included in order to aid in the recognition of this curious myxomycete-looking thermophilou s, anamorphic species, saprotrophic on nutrient-rich substrata, and so different from the usual Penicillium taxa

Multilevel annoyance modelling of short environmental sound recordings

The recent development and deployment of Wireless Acoustic Sensor Networks (WASN) present new ways to address urban acoustic challenges in a smart city context. A focus on improving quality of life forms the core of smart-city design paradigms and cannot be limited to simply measuring objective environmental factors, but should also consider the perceptual, psychological and health impacts on citizens. This study therefore makes use of short (1–2.7 s) recordings sourced from a WASN in Milan which were grouped into various environmental sound source types and given an annoyance rating via an online survey with N = 100 participants. A multilevel psychoacoustic model was found to achieve an overall R = 0.64 which incorporates Sharpness as a fixed effect regardless of the sound source type and Roughness, Impulsiveness and Tonality as random effects whose coefficients vary depending on the sound source. These results present a promising step toward implementing an on-sensor annoyance model which incorporates psychoacoustic features and sound source type, and is ultimately not dependent on sound level.

Proteomic identification of prognostic tumour biomarkers, using chemotherapy-induced cancer-associated fibroblasts

Cancer cells grow in highly complex stromal microenvironments, which through metabolic remodelling, catabolism, autophagy and inflammation nurture them and are able to facilitate metastasis and resistance to therapy. However, these changes in the metabolic profile of stromal cancer-associated fibroblasts and their impact on cancer initiation, progression and metastasis are not well-known. This is the first study to provide a comprehensive proteomic portrait of the azathioprine and taxol-induced catabolic state on human stromal fibroblasts, which comprises changes in the expression of metabolic enzymes, myofibroblastic differentiation markers, antioxidants, proteins involved in autophagy, senescence, vesicle trafficking and protein degradation, and inducers of inflammation. Interestingly, many of these features are major contributors to the aging process. A catabolic stroma signature, generated with proteins found differentially up-regulated in taxol-treated fibroblasts, strikingly correlates with recurrence, metastasis and poor patient survival in several solid malignancies. We therefore suggest the inhibition of the catabolic state in healthy cells as a novel approach to improve current chemotherapy efficacies and possibly avoid future carcinogenic processes