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691.
692.
Elizabeth R. Selig Catherine Longo Benjamin S. Halpern Benjamin D. Best Darren Hardy Cristiane T. Elfes Courtney Scarborough Kristin M. Kleisner Steven K. Katona 《PloS one》2013,8(4)
People value the existence of a variety of marine species and habitats, many of which are negatively impacted by human activities. The Convention on Biological Diversity and other international and national policy agreements have set broad goals for reducing the rate of biodiversity loss. However, efforts to conserve biodiversity cannot be effective without comprehensive metrics both to assess progress towards meeting conservation goals and to account for measures that reduce pressures so that positive actions are encouraged. We developed an index based on a global assessment of the condition of marine biodiversity using publically available data to estimate the condition of species and habitats within 151 coastal countries. Our assessment also included data on social and ecological pressures on biodiversity as well as variables that indicate whether good governance is in place to reduce them. Thus, our index is a social as well as ecological measure of the current and likely future status of biodiversity. As part of our analyses, we set explicit reference points or targets that provide benchmarks for success and allow for comparative assessment of current conditions. Overall country-level scores ranged from 43 to 95 on a scale of 1 to 100, but countries that scored high for species did not necessarily score high for habitats. Although most current status scores were relatively high, likely future status scores for biodiversity were much lower in most countries due to negative trends for both species and habitats. We also found a strong positive relationship between the Human Development Index and resilience measures that could promote greater sustainability by reducing pressures. This relationship suggests that many developing countries lack effective governance, further jeopardizing their ability to maintain species and habitats in the future. 相似文献
693.
Antonella Capozzi Olimpia Vincentini Pietro Gizzi Alessandra Porzia Agostina Longo Cristina Felli Vincenzo Mattei Fabrizio Mainiero Marco Silano Maurizio Sorice Roberta Misasi 《PloS one》2013,8(6)
Celiac Disease (CD) is a chronic inflammatory enteropathy, triggered in genetically susceptible individuals by dietary gluten. Gluten is able to elicit proliferation of specific T cells and secretion of inflammatory cytokines in the small intestine. In this study we investigated the possibility that p10-mer, a decapeptide from durum wheat (QQPQDAVQPF), which was previously shown to prevent the activation of celiac peripheral lymphocytes, may exert an inhibitory effect on peptic-tryptic digested gliadin (PT-Gly)-stimulated intestinal carcinoma CACO-2 cells. In these cells, incubated with PT-Gly or p31-43 α-gliadin derived peptide in the presence or in the absence of p10-mer, IRAK1 activation and NF-kB, ERK1/2 and p38 MAPK phosphorylation were measured by immunoblotting, Cyclooxigenase 2 (COX-2) activity by PGE-2 release assay, and production of cytokines in the cell supernatants by ELISA. Our results showed that pre-treatment of CACO-2 cells with p10-mer significantly inhibited IRAK1 activation and NF-kB, ERK1/2 and p38 MAPK phosphorylation, as well as COX-2 activity (i.e. PGE-2 release) and production of the IL-6 and IL-8 pro-inflammatory cytokines, induced by gliadin peptides. These findings demonstrate the inhibitory effect of the p10-mer peptide on inflammatory response in CACO-2 cells. The results of the present study show that this p10-mer peptide can modulate "in vitro" the inflammatory response induced by gliadin peptides, allowing to move towards new therapeutic strategies. Turning off the inflammatory response, may in fact represent a key target in the immunotherapy of celiac disease. 相似文献
694.
Maurício Cantor Mathias Mistretta Pires Guilherme Ortigara Longo Paulo Roberto Guimarães Jr. Eleonore Zulnara Freire Setz 《Oikos》2013,122(7):1085-1093
Despite recent findings on the ecological relevance of within population diet variation far less attention has been devoted to the role diet variation for ecological services. Seed dispersal is a key ecological service, affecting plant fitness and regeneration based on foraging by fruit‐eating vertebrates. Here we used a network approach, widely used to understand how seed‐dispersal is organized at the species level, to gain insights into the patterns that emerge at the individual‐level. We studied the individual fruit consumption behavior of a South American didelphid Didelphis albiventris, during the cool–dry and warm–wet seasons. In species–species networks the heterogeneity in specialization levels generates patterns such as nestedness and asymmetry. Because generalist populations may be comprised of specialized individuals, we hypo thesized that network structural properties, such as nestedness, should also emerge at the individual level. We detected variation in fruit consumption that was not related to resource availability, ontogenetic or sexual factors or sampling biases. Such variation resulted in the structural patterns often found in species–species seed‐dispersal networks: low connectance, a high degree of nestedness and the absence of modules. Moreover structure varied between the warm–wet and cool–dry seasons, presumably as a consequence of seasonal fluctuation in fruit availability. Our findings suggest individuals may differ in selectivity causing asymmetries in seed dispersal efficiency within the population. In this sense the realized dispersal would differ from the expected dispersal estimated from their average dispersal potential. Additionally the results suggest possible frequency‐dependent effects on seed dispersal that might affect individual plant performance and plant community composition. 相似文献
695.
Clark M. Henderson Wade F. Zeno Larry A. Lerno Marjorie L. Longo David E. Block 《Applied and environmental microbiology》2013,79(17):5345-5356
During alcoholic fermentation, Saccharomyces cerevisiae is exposed to a host of environmental and physiological stresses. Extremes of fermentation temperature have previously been demonstrated to induce fermentation arrest under growth conditions that would otherwise result in complete sugar utilization at “normal” temperatures and nutrient levels. Fermentations were carried out at 15°C, 25°C, and 35°C in a defined high-sugar medium using three Saccharomyces cerevisiae strains with diverse fermentation characteristics. The lipid composition of these strains was analyzed at two fermentation stages, when ethanol levels were low early in stationary phase and in late stationary phase at high ethanol concentrations. Several lipids exhibited dramatic differences in membrane concentration in a temperature-dependent manner. Principal component analysis (PCA) was used as a tool to elucidate correlations between specific lipid species and fermentation temperature for each yeast strain. Fermentations carried out at 35°C exhibited very high concentrations of several phosphatidylinositol species, whereas at 15°C these yeast strains exhibited higher levels of phosphatidylethanolamine and phosphatidylcholine species with medium-chain fatty acids. Furthermore, membrane concentrations of ergosterol were highest in the yeast strain that experienced stuck fermentations at all three temperatures. Fluorescence anisotropy measurements of yeast cell membrane fluidity during fermentation were carried out using the lipophilic fluorophore diphenylhexatriene. These measurements demonstrate that the changes in the lipid composition of these yeast strains across the range of fermentation temperatures used in this study did not significantly affect cell membrane fluidity. However, the results from this study indicate that fermenting S. cerevisiae modulates its membrane lipid composition in a temperature-dependent manner. 相似文献
696.
697.
Alexandro Cézar Faleiro Tomás Pellizzaro Pereira Eliandro Espindula Fábio Cristiano Angonesi Brod Ana Carolina Maisonnave Arisi 《Symbiosis (Philadelphia, Pa.)》2013,61(3):125-133
The plant growth promoting bacteria (PGPB) Azospirillum brasilense has been recommended for use in commercial inoculants in Brazil. Effective methods are necessary to monitor PGPB strains in the rhizosphere. Our purpose was to develop a real time PCR method for detection of A. brasilense strain FP2 in maize seedlings targeting nifA. Primer pairs were designed and their specificity was verified using DNA from 12 different bacterial species. Standard curves were prepared for DNA quantification using serial dilution of A. brasilense DNA extracts. PCR efficiencies and correlation coefficient presented values within the acceptable range for qPCR, mean PCR efficiency was 95 % and correlation coefficient was 0.98, indicating that nifA gene was suitable for the quantitative analysis of the target bacterial genome. Inoculated maize seedlings were grown in vitro or in pots, bacterial DNA copy number per gram of fresh root was quantified 1, 4, 7 and 10 days after inoculation. The developed primers targeting nifA will be useful for monitoring Azospirillum brasilense strain FP2 in crops. 相似文献
698.
Alberto Ceccon Mariapina D'Onofrio Serena Zanzoni Dario Livio Longo Silvio Aime Henriette Molinari Michael Assfalg 《Proteins》2013,81(10):1776-1791
Membrane binding by cytosolic fatty acid binding proteins (FABP) appears to constitute a key step of intracellular lipid trafficking. We applied NMR spectroscopy to study the partitioning of a water‐soluble bile acid binding protein (BABP), belonging to the FABP family, between its free and lipid‐vesicle‐bound states. As the lipid‐bound protein was NMR‐invisible, the signals of the free biomolecule were analyzed to obtain quantitative information on binding affinity and steady‐state kinetics. The data indicated a reversible interaction of BABP with anionic vesicles occurring in a very slow exchange regime on the NMR time scale. The approximate binding epitope was demonstrated from results on BABP samples in which different positively charged lysine residues were mutated to neutral alanines. H/D exchange measurements indicated a higher exposure to solvent for the core amino acid residues in the liposome‐bound state. Finally, the BABP‐liposome interaction was also investigated for the first time through an MRI‐chemical exchange saturation transfer experiment that has potential applications not only in the field of biology, but also in biomedicine, bioanalytical chemistry, and nanotechnology. Proteins 2013; 81:1776–1791. © 2013 Wiley Periodicals, Inc. 相似文献
699.
Cristiano Ribeiro Viana Cristovam Scapulatempo Neto Ligia Maria Kerr Edenir Inêz Palmero Marcia Maria Chiquitelli Marques Tamara Colaiacovo Abel Feliciano de Queiroz Junior André Lopes Carvalho Sheila Aparecida Coelho Siqueira 《Cell and tissue banking》2013,14(2):167-173
Tumor Banks were created to organize the collection, storage and distribution of biological samples from oncological patients, facilitating its use in cancer research. To ensure the quality of the samples from our bank, we implemented standard operating procedures international. In order to evaluate the influence of cold ischemia time (time between surgical removal of the specimen and the snap freezing of the sample) on the quality of the samples (evaluated by measurement integrity of their RNA), collected during 10 months two tumor samples from each donor, one with up to 30 min of cold ischemia and other with exact 45 min, totaling 100 different donors and 200 samples, 40 from each of the following organs: breast, thyroid, stomach, lung and colorectum. We extracted total RNA from the samples and with the aid of a Bioanalyser, evaluate their quality, comparing it with cold ischemia times in different organs. Among the samples up to 30 min and the samples with exact 45 min, we respectively found 63 (64.3 %) and 36 (36 %) with intact RNA, 11 (11.2 %) and 17 (17 %) partially degraded and 24 (24.5 %) and 47 (47 %) degraded (p < 0.001). Thyroid and colorectal samples were more sensitive to variations in cold ischemia time (p = 0.006 and p = 0.03, respectively). Stomach and lungs were less sensitive (p = 0.919 and p = 0.384, respectively). We concluded that the cold ischemia time up to 30 min was more efficient to maintain the integrity of RNA in most samples, and that RNA degradation varied according to the different topographies. 相似文献
700.
Abstract Low amplitude swelling in isolated pea mitochondria. — The authors have studied the volume changes of isolated pea internode mitochondria occurring in a medium which allows the oxidative activity to proceed. With succinate as substrate respiratory control ratios as high as 9 have been obtained. They can be taken as an index of a tight coupling of mitochondria. The adding of succinate induces on the other hand a slight but continuous swelling which is strongly enhanced by ADP or ATP. Inhibitors of the respiratory chain like antimycin A and of the phosphorylation reactions like atractylate or oligomycin block completely the ADP or ATP-induced swelling. 2,4-dinitrophenol at 5×10?6 M concentration exerts a strong inhibitory action on succinate oxidation and on swelling. Both actions of 2,4-DNP can be reversed by ATP. It can be concluded from these findings that the substances which slow down or abolish the oxidative and phosphorylative reactions inhibit also mitochondrial swelling. This type of volume changes appears therefore to be strictly energy-dependent. 相似文献