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991.
Beatriz Mart��nez-Poveda Salvador Rodr��guez-Nieto Melissa Garc��a-Caballero Miguel-��ngel Medina Ana R. Quesada 《Marine drugs》2012,10(9):2033-2046
Aeroplysinin-1 is a brominated metabolite extracted from the marine sponge Aplysina aerophoba that has been previously characterized by our group as a potent antiangiogenic compound in vitro and in vivo. In this work, we provide evidence of a selective induction of apoptosis by aeroplysinin-1 in endothelial cells. Studies on the nuclear morphology of treated cells revealed that aeroplysinin-1 induces chromatin condensation and nuclear fragmentation, and it increases the percentage of cells with sub-diploid DNA content in endothelial, but not in HCT-116, human colon carcinoma and HT-1080 human fibrosarcoma cells. Treatment of endothelial cells with aeroplysinin-1 induces activation of caspases-2, -3, -8 and -9, as well as the cleavage of apoptotic substrates, such as poly (ADP-ribose) polymerase and lamin-A in a caspase-dependent mechanism. Our data indicate a relevant role of the mitochondria in the apoptogenic activity of this compound. The observation that aeroplysinin-1 prevents the phosphorylation of Bad relates to the mitochondria-mediated induction of apoptosis by this compound. 相似文献
992.
Laura Nú?ez-Pons Marianna Carbone Jennifer Vázquez Jaime Rodríguez Rosa María Nieto María Mercedes Varela Margherita Gavagnin Conxita Avila 《Marine drugs》2012,10(8):1741-1764
Ascidians have developed multiple defensive strategies mostly related to physical, nutritional or chemical properties of the tunic. One of such is chemical defense based on secondary metabolites. We analyzed a series of colonial Antarctic ascidians from deep-water collections belonging to the genera Aplidium and Synoicum to evaluate the incidence of organic deterrents and their variability. The ether fractions from 15 samples including specimens of the species A. falklandicum, A. fuegiense, A. meridianum, A. millari and S. adareanum were subjected to feeding assays towards two relevant sympatric predators: the starfish Odontaster validus, and the amphipod Cheirimedon femoratus. All samples revealed repellency. Nonetheless, some colonies concentrated defensive chemicals in internal body-regions rather than in the tunic. Four ascidian-derived meroterpenoids, rossinones B and the three derivatives 2,3-epoxy-rossinone B, 3-epi-rossinone B, 5,6-epoxy-rossinone B, and the indole alkaloids meridianins A–G, along with other minoritary meridianin compounds were isolated from several samples. Some purified metabolites were tested in feeding assays exhibiting potent unpalatabilities, thus revealing their role in predation avoidance. Ascidian extracts and purified compound-fractions were further assessed in antibacterial tests against a marine Antarctic bacterium. Only the meridianins showed inhibition activity, demonstrating a multifunctional defensive role. According to their occurrence in nature and within our colonial specimens, the possible origin of both types of metabolites is discussed. 相似文献
993.
María Elena Cartea Víctor Manuel Rodríguez Antonio de Haro Pablo Velasco Amando Ordás 《Euphytica》2008,159(1-2):111-122
Glucosinolate levels in leaves were determined in a collection of 36 varieties of nabicol (Brassica napus
pabularia group) from northwestern Spain grown at two locations. Crude protein, acid detergent fibre, and sensory traits were also
assessed by a consumer panel. The objectives were to determine the diversity among varieties in total glucosinolate content
and glucosinolate profile and to evaluate their sensory attributes in relation to glucosinolate content for breeding purposes.
Eight glucosinolates were identified, being the aliphatic glucosinolates, glucobrassicanapin, progoitrin, and gluconapin the
most abundant. Glucosinolate composition varied between locations although the glucosinolate pattern was not significantly
influenced. Differences in total glucosinolate content, glucosinolate profile, protein, acid detergent fibre, and flavour
were found among varieties. The total glucosinolate content ranged from 1.4 μmol g−1 to 41.0 μmol g−1 dw at one location and from 1.2 μmol g−1 to 7.6 μmol g−1 dw at the other location. Sensory analysis comparing bitterness and flavour with variation in glucosinolate, gluconapin, progoitrin,
and glucobrassicanapin concentrations suggested that other phytochemicals are probably involved on the characteristic flavour.
The variety MBG-BRS0035 had high total glucosinolate, glucobrassicanapin, and gluconapin contents at both locations and could
be included in breeding programs to improve the nutritional value of this vegetable crop. 相似文献
994.
Rodríguez-Acuña R Brenne E Lacoste F 《Journal of agricultural and food chemistry》2008,56(15):6241-6245
A new sensitive and selective method has been developed for the quantification of the total coenzyme Q9 (CoQ9) and coenzyme Q10 (CoQ10) concentration in vegetable oil samples. The coenzyme Q fraction is isolated by solid-phase extraction (SPE) on amino phase eluting with a mixture of heptane:ethyl ether. The organic solvent is evaporated under nitrogen, and the residue is dissolved in a mixture of acetonitrile:tetrahydrofuran and finally is analyzed by reverse-phase high-performance liquid chromatography with a mass detector. The sensitivity of the method is based on the high efficient formation of the radical anions [M (-.)] of CoQ9 and CoQ10 by negative atmospheric pressure ionization. Interferences are minimized by using mass detection of the [M (-.)] ions ( m/ z = 797.5 for CoQ9 and m/ z = 862.5 for CoQ10) in selective reaction monitoring mode ( m/ z = 797.5 --> m/ z = 779.5 and m/ z = 862.5 --> m/ z = 847.5) using a triple-quadrupole mass spectrometer. The method was successfully applied to sunflower, soybean, and rapeseed oils, with a limit of quantification of 0.025 mg/kg for both compounds. 相似文献
995.
Rodríguez-Bencomo JJ Ortega-Heras M Pérez-Magariño S González-Huerta C González-San José ML 《Journal of agricultural and food chemistry》2008,56(13):5102-5111
The evolution of volatile compounds extracted from wood while being macerated for 1 month with four different commercial chips (different geographical origins and toasting degrees) was studied. Furthermore, the effect of the microoxygenation process between alcoholic and malolactic fermentation also was studied. The wood volatile compounds in wines macerated with the four types of chips evolved in the same way. However, the amounts of compounds extracted depended on the type of chip used. There were differences in the levels of vanillin, cis-whiskey lactone, furfural, trans-isoeugenol, and cis-isoeugenol in wines in accordance with the type of wood chips (French or American), and the last two compounds along with 5-methyl furfural presented differences that were directly related to the toast level. However, no effects of microoxygenation treatment on the extraction of volatile compounds extracted from chips were observed. Therefore, the results obtained in this study highlight the importance of chip selection on the aromatic characteristics of finished wines. 相似文献
996.
César Rodríguez-Sánchez Karlheinz Altendorf Kornelia Smalla André Lipski 《Biology and Fertility of Soils》2008,44(4):589-596
Horticultural supplements containing oxytetracycline and gentamicin, two clinically relevant biocides, are widely marketed
to prevent or control infections by bacterial phytopathogens. Despite their regular consumption in the world’s less developed
countries, it is unknown whether exposure of tropical farmlands to these drugs results in an enrichment of resistant bacteria,
resistance genes, and/or mobile genetic elements in the soil. These concerns were investigated under field conditions by repeatedly
spraying recommended amounts of a commercial product containing oxytetracycline-HCl, and gentamicin- onto two coriander plots. Subsequent to five applications within 16 months, composite soil samples from control and treated
sections were compared with respect to the abundance of resistant bacteria and the prevalence of conserved nucleotide sequences
from tetracycline efflux proteins, tetracycline ribosomal protection proteins, four different families of gentamicin-modifying
enzymes, and broad host range plasmids of the IncP-1 and IncQ incompatibility groups. The isolation frequency of oxytetracycline-
and gentamicin-resistant bacteria and the detection rate of the aforementioned genes and elements were unrelated to application
of the supplement. Despite the omnipresence of sequences from IncP-1 plasmids, conjugative plasmids conferring resistance
to oxytetracycline or gentamicin were not captured in biparental matings. The widespread occurrence of resistant bacteria
and resistance genes at the beginning of the trial emerges as a reasonable explanation for the lack of anticipated responses.
Moreover, we assume that the biocides applied were inactivated by biotic and abiotic factors under tropical conditions. 相似文献
997.
J. A. Rodríguez-Suárez B. Soto M. L. Iglesias F. Diaz-Fierros 《European Journal of Forest Research》2010,129(4):573-583
This paper presents an assessment of the ability of the 3PG process-based model to simulate height (h) and diameter at breast height (DBH) growth in three plots located in a Eucalyptus globulus plantation on the Atlantic coast of Galicia (Northwest Spain). The obtained results show how this model estimates adequately
height (h) and DBH growth, and determination coefficients (R
2) between observed data and data predicted by the model are always higher than 0.97, root mean square error (RMSE) of 0.45–1.05 cm
in DBH and 0.46–0.85 in h, and a model efficiency (EF) close to 1 (0.98–0.99). In order to improve the results predicted by the model, we propose modifying
the nS and fullCanAge parameter values given by default so as to adjust growth rates in the plantation to the weather conditions in the site. The
ability of the model to discriminate growth rates in the three plots must be noted, even when plots are located in the same
plantation and they only show differences in aspects related to site factors. Given the obtained results in the three plots
used in this study, its simplicity and the small number of parameters needed as input data, the 3PG model stands out as a
very useful tool for forest plantation management. 相似文献
998.
Barreda VD Palazzesi L Tellería MC Katinas L Crisci JV Bremer K Passalia MG Corsolini R Rodríguez Brizuela R Bechis F 《Science (New York, N.Y.)》2010,329(5999):1621
Fossil capitula and pollen grains of Asteraceae from the Eocene of Patagonia, southern Argentina, exhibit morphological features recognized today in taxa, such as Mutisioideae and Carduoideae, that are phylogenetically close to the root of the asteracean tree. This fossil supports the hypothesis of a South American origin of Asteraceae and an Eocene age of divergence and suggests that an ancestral stock of Asteraceae may have formed part of a geoflora developed in southern Gondwana before the establishment of effective dispersal barriers within this landmass. 相似文献
999.
A. A. Rigueiro‐Rodríguez N. Ferreiro‐Domínguez M. R. Mosquera‐Losada 《Grass and Forage Science》2010,65(2):248-259
In silvopastoral systems, tree growth and the composition and productivity of pasture can be modified by management practices such as initial fertilization when tree seedlings are more sensitive to understorey competition. The aim of this study was to compare the effects of fertilization with different types of sewage sludge (anaerobic sludge, composted sludge and pelletized sludge), using different rates of incorporation and mineralization with traditional treatments (with and without mineral fertilizers) on the growth of newly established ash (Fraxinus excelsior L.) and on pasture development, to obtain sustainable management practices that enhance the growth of both components. Soil characteristics, tree growth, sward composition and pasture development were modified differently according to the type of sewage sludge used, and for similar total nitrogen inputs. Anaerobic sludge had a higher initial effect on both tree and pasture productivity. Pelletized sludge sustained better tree and pasture production. Composted sludge was found to be the most appropriate treatment for improving soil characteristics over the long term on sandy soils. It was concluded that pelletized sludge should be promoted because it enhances productivity, allows for better nutrient recovery and is less costly to store and apply compared with anaerobic sludge and composted sludge. No toxic concentrations of Zn or Cu were found in plants or in the soil despite higher concentrations being present in the applied sludge than in soil. 相似文献
1000.
P. Gómez A.M. Rodríguez-Hernández B. Moury M.A. Aranda 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):1-22
Plant viruses are important agricultural pathogens, and are responsible for a significant number of commercially relevant
plant diseases. There are very few efficient control measures for viral diseases, but the use of genetic resistance appears
to be the most promising strategy, often conferring effective protection without additional costs or labour during the growing
season, and without damaging the environment. Sources of virus resistance have been identified for most crop species, and
many resistant cultivars are already commercially available and of widespread cultivation; however, much remains to be learned
about genetic resistance. This review article considers three main aspects that require intense investigation. First, we review
the identification of sources of resistance and how plant breeders and pathologists have focused on aspects of the breeding
process particularly relevant to viruses, such as germplasm screening and the dissection of resistance phenotypes. Second,
we review how molecular mechanisms controlling resistance have been unravelled, looking at case studies where resistance mechanisms
are now understood in detail for each stage of the infection cycle. Third, we turn to the durability of resistance in a global
context, examining factors that influence durability and how this can be predicted. We conclude with a short discussion of
the technological and scientific opportunities provided by recent advances in the field. 相似文献