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21.
Virginie Riou Debany Fonseca-Batista Arnout Roukaerts Isabelle C. Biegala Shree Ram Prakya Clara Magalh?es Loureiro Mariana Santos Angel E. Muniz-Piniella Mara Schmiing Marc Elskens Natacha Brion M. Ana Martins Frank Dehairs 《PloS one》2016,11(3)
To understand the impact of the northwestern Azores Current Front (NW-AzC/AzF) system on HCO3−-and N2-fixation activities and unicellular diazotrophic cyanobacteria (UCYN) distribution, we combined geochemical and biological approaches from the oligotrophic surface to upper mesopelagic waters. N2-fixation was observed to sustain 45–85% of the HCO3−-fixation in the picoplanktonic fraction performing 47% of the total C-fixation at the deep chlorophyll maximum north and south of the AzF. N2-fixation rates as high as 10.9 μmol N m-3 d-1 and surface nitrate δ15N as low as 2.7‰ were found in the warm (18–24°C), most saline (36.5–37.0) and least productive waters south of the AzF, where UCYN were the least abundant. However, picoplanktonic UCYN abundances up to 55 cells mL-1 were found at 45–200m depths in the coolest nutrient-rich waters north of the AzF. In this area, N2-fixation rates up to 4.5 μmol N m-3 d-1 were detected, associated with depth-integrated H13CO3−-fixation rates at least 50% higher than observed south of the AzF. The numerous eddies generated at the NW-AzC/AzF seem to enhance exchanges of plankton between water masses, as well as vertical and horizontal diapycnal diffusion of nutrients, whose increase probably enhances the growth of diazotrophs and the productivity of C-fixers. 相似文献
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Sabrina I?igo Astrid Nagels Durand Andrés Ritter Sabine Le Gall Martin Termathe Roland Klassen Takayuki Tohge Barbara De Coninck Jelle Van Leene Rebecca De Clercq Bruno P.A. Cammue Alisdair R. Fernie Kris Gevaert Geert De Jaeger Sebastian A. Leidel Raffael Schaffrath Mieke Van Lijsebettens Laurens Pauwels Alain Goossens 《Plant physiology》2016,172(2):858-873
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Iñigo Zuberogoitia Jabi Zabala Jon Etxezarreta Ariñe Crespo Gorka Burgos Juan Arizaga 《Population Ecology》2016,58(2):303-313
Climate change affects the climatic disturbance patterns and regimes and is altering the frequency and intensity of subtropical cyclones. These events can affect population dynamics of seabirds (e.g., survival, reproduction). In this work we tested the effect of adverse weather on a colony of European storm petrels (Hydrobates pelagicus) located in a small islet (Aketx) in northern Spain. Over a long-term monitoring period (1993–2014) we ringed 3728 petrels. From 2003 onwards we also monitored breeding success, the percentage of immature individuals and moult scores. We used Cormack-Jolly-Seber models and Underhill and Zucchini models to analyze the effects of climatic conditions on a number of biological traits (survival, breeding parameters, moulting patterns). Our analyses revealed a constant value of adult survival over the 26-year monitoring period. Recapture probability, however, tended to be positively influenced by NAO conditions in spring, and negatively influenced by NAO conditions in winter (although this would only affect to a fraction of first-captured birds). Moreover, the impact of adverse weather, especially in 2011 and 2014, resulted in an increasing proportion of yearlings in the breeding population, a lower breeding success and a delayed onset of moult. These effects were similar to those observed during the Prestige oil spill catastrophe. 相似文献
26.
Einar Vargas-Bello-Pérez Gonzalo Íñiguez-González Nathaly Cancino-Padilla Juan J. Loor Philip C. Garnsworthy 《Archives of animal nutrition》2016,70(4):322-332
The aim of this study was to elucidate the effect of dietary supplementation of soybean oil (SO) and hydrogenated palm oil (HPO) on the transport of fatty acids (FA) within plasma lipoproteins in lactating and non-lactating cows. Three lactating and three non-lactating Holstein cows were used in two different 3 × 3 Latin square experiments that included three periods of 21 d. Dietary treatments for lactating cows consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (500 g/d per cow) or HPO (500 g/d per cow). For non-lactating cows, dietary treatments consisted of a basal diet (control; no fat supplement) and fat-supplemented diets containing SO (170 g/d per cow) or HPO (170 g/d per cow). Compared with the control and SO diet, HPO addition increased (p < 0.05) the concentration of C16:0, C18:0, C18:2cis-9,12, C18:3cis-9,12,15 and total saturated and polyunsaturated FA in the plasma of lactating cows. In non-lactating cows, the SO addition increased the plasma concentration of C18:1trans-11. In lactating cows, concentrations of C16:0, C18:0 and total saturated FA were increased (p < 0.05) by HPO addition in the high-density lipoprotein (HDL). Total saturated FA were increased (p < 0.05) by HPO in very-low-density lipoprotein (VLDL). In non-lactating cows, the concentration of C18:0 was increased (p < 0.05) by HPO in HDL, whereas C18:1trans-11 was increased (p < 0.05) by SO in the low-density lipoprotein. Overall, it was found that distribution and transport of FA within the bovine plasma lipoproteins may be influenced by chain length and degree of unsaturation of dietary lipids. Also, the distribution of individual FA isomers such as C18:1trans-11 and C18:2cis-9,trans-11 may vary depending on the physiological state of the cow (lactating or non-lactating), and are increased in plasma (lactating cows) and the HDL (non-lactating cows) when cows are fed SO. 相似文献
27.
Alan Walton Elisabeth Stes Nicolas Cybulski Michiel Van Bel Sabrina I?igo Astrid Nagels Durand Evy Timmerman Jefri Heyman Laurens Pauwels Lieven De Veylder Alain Goossens Ive De Smet Frederik Coppens Sofie Goormachtig Kris Gevaert 《The Plant cell》2016,28(1):6-16
Ubiquitination, the covalent binding of the small protein modifier ubiquitin to a target protein, is an important and frequently studied posttranslational protein modification. Multiple reports provide useful insights into the plant ubiquitinome, but mostly at the protein level without comprehensive site identification. Here, we implemented ubiquitin combined fractional diagonal chromatography (COFRADIC) for proteome-wide ubiquitination site mapping on Arabidopsis thaliana cell cultures. We identified 3009 sites on 1607 proteins, thereby greatly increasing the number of known ubiquitination sites in this model plant. Finally, The Ubiquitination Site tool (http://bioinformatics.psb.ugent.be/webtools/ubiquitin_viewer/) gives access to the obtained ubiquitination sites, not only to consult the ubiquitination status of a given protein, but also to conduct intricate experiments aiming to study the roles of specific ubiquitination events. Together with the antibodies recognizing the ubiquitin remnant motif, ubiquitin COFRADIC represents a powerful tool to resolve the ubiquitination maps of numerous cellular processes in plants. 相似文献
28.
Thiago Doria Barral Ricardo Barros Mariutti Raghuvir Krishnaswamy Arni Anderson Jesus Santos Dan Loureiro Ana Rita Sokolonski Vasco Azevedo Sibele Borsuk Roberto Meyer Ricardo Dias Portela 《Microbial biotechnology》2019,12(6):1313-1323
Caseous lymphadenitis (CLA) is a small ruminant disease characterized by the development of granulomatous lesions in superficial and internal lymph nodes, as well as in some organs, and causes significant economic losses worldwide. The aetiological agent of CLA is the bacterium Corynebacterium pseudotuberculosis; however, the commercially available diagnostic tools present problems with regard to specificity, which can lead to false-negative results. This study aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) for the detection of specific immunoglobulins in goats and sheep using recombinant C. pseudotuberculosis PLD, CP40, PknG, DtxR and Grx proteins. For validation of the ELISAs, 130 goat serum samples and 160 sheep serum samples were used. The best ELISA for goats was developed using a combination of PLD and CP40 as antigens at a 1:1 ratio, which presented 96.9% sensitivity and 98.4% specificity. The most effective ELISA for sheep presented 91% sensitivity and 98.7% specificity when recombinant PLD alone was used as the antigen. These ELISAs can be used as highly accurate tools in epidemiological surveys and for the serodiagnosis of C. pseudotuberculosis infection in goats and sheep. 相似文献
29.
Caio Loureiro Salgado Emmanoel Loss Dias Lorenzzo Lyrio Stringari Luciana Polaco Covre Reynaldo Dietze Fausto Edmundo Lima Pereira Herbet Leonel de Matos Guedes Bartira Rossi-Bergmann Daniel Claudio Oliveira Gomes 《Microbes and infection / Institut Pasteur》2019,21(7):328-335
The use of adjuvants in vaccine formulations is a well-established practice to improve immunogenicity and protective immunity against diseases. Previously, we have demonstrated the feasibility of intranasal vaccination with the antigen of killed Leishmania amazonensis promastigotes (LaAg) against experimental leishmaniasis. In this work, we sought to optimize the immunogenic effect and protective immunity against murine visceral leishmaniasis conferred by intranasal delivery of LaAg in combination with a synthetic TLR1/TLR2 agonist (Pam3CSK4). Intranasal vaccination with LaAg/PAM did not show toxicity or adverse effects, induced the increase of delayed-type hypersensitivity response and the production of inflammatory cytokines after parasite antigen recall. However, mice vaccinated with LaAg/PAM and challenged with Leishmania infantum presented significant reduction of parasite burden in both liver and spleen, similar to those vaccinated with LaAg. Although LaAg/PAM intranasal vaccination had induced higher frequencies of specific CD4+ and CD8+ T cells and increased levels of IgG2a antibody isotype in serum, both LaAg and LaAg/PAM groups presented similar levels of IL-4 and IFN-y and decreased production of IL-10 when compared to controls. Our results provide the first evidence of the feasibility of intranasal immunization with antigens of killed Leishmania in association with a TLR agonist, which may be explored for developing an effective and alternative strategy for vaccination against visceral leishmaniasis. 相似文献