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Applied Microbiology and Biotechnology - A SYBR Green I real-time polymerase chain reaction protocol for specific detection of the fish pathogen Aeromonas salmonicida subsp. salmonicida was...  相似文献   
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In this study different bacterial inoculation methods were tested for tobacco plants growing in a mine-soil contaminated with Pb, Zn, and Cd. The inoculation methods evaluated were: seed inoculation, soil inoculation, dual soil inoculation event, and seed+soil inoculation. Each inoculum was added at two bacterial densities (106 CFUs mL?1 and 108 CFUs mL?1). The objectives were to evaluate whether or not the mode of inoculation or the number of applied microorganisms influences plant response. The most pronounced bacterial-induced effect was found for biomass production, and the soil inoculation treatment (using 106 CFUs mL?1) led to the highest increase in shoot dry weight yield (up to 45%). Bacterial-induced effects on shoot metal concentrations were less pronounced; although a positive effect was found on shoot Pb concentration when using 108 CFUs mL?1 in the soil inoculation (29% increase) and in the seed+soil inoculation (34% increase). Also shoot Zn concentration increased by 24% after seed inoculation with 106 CFUs mL?1. The best effects on the total metal yield were not correlated with an increasing number of inoculated bacteria. In fact the best results were found after a single soil inoculation using the lower cellular density of 106 CFUs mL?1.  相似文献   
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ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family is known to play an important role in the pathogenesis of osteoarthritis (OA), working on aggrecan degradation or altering the integrity of extracellular matrix (ECM). Thus, the main purpose of our study was to define the role of vasoactive intestinal peptide (VIP) and corticotrophin‐releasing factor (CRF), as immunoregulatory neuropeptides, on ADAMTS production in synovial fibroblasts (SF) from OA patients and healthy donors (HD). OA‐ and HD‐SF were stimulated with pro‐inflammatory mediators and treated with VIP or CRF. Both neuropeptides decreased ADAMTS‐4, ‐5, ‐7 and ‐12 expressions, aggrecanase activity, glycosaminoglycans (GAG), and cartilage oligomeric matrix protein (COMP) degradation after stimulation with fibronectin fragments (Fn‐fs) in OA‐SF. After stimulation with interleukin‐1β, VIP reduced ADAMTS‐4 and ‐5, and both neuropeptides decreased ADAMTS‐7 production and COMP degradation. Moreover, VIP and CRF reduced Runx2 and β‐catenin activation in OA‐SF. Our data suggest that the role of VIP and CRF on ADAMTS expression and cartilage degradation could be related to the OA pathology since scarce effects were produced in HD‐SF. In addition, their effects might be greater when a degradation loop has been established, given that they were higher after stimulation with Fn‐fs. Our results point to novel OA therapies based on the use of neuropeptides, since VIP and CRF are able to stop the first critical step, the loss of cartilage aggrecan and the ECM destabilization during joint degradation.  相似文献   
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Verticillium wilt, caused by Verticillium dahliae Kleb., is presently the most destructive disease of olive, particularly in Andalucía (southern Spain). ‘Picual’ and ‘Arbequina’ are the dominant cultivars being planted in Spain. Both cultivars are highly susceptible to the defoliating pathotype of V. dahliae when artificially inoculated by root‐dipping or stem injection. Conversely, ‘Arbequina’ is considered more resistant than ‘Picual’ based on field observations and farmer's experience. In this study, the differential reaction between of cultivars was confirmed by surveys of naturally infested orchards with different inoculum densities of the pathogen. The average percentage of affected olive trees of ‘Picual’ was 60.2%, while only 13.1% of trees of ‘Arbequina’ showed disease symptoms. Overall, the pathogen caused extensive wilting of branches and defoliation on the trees of ‘Picual’, whereas ‘Arbequina’‐infected trees showed chlorotic symptoms and slight defoliation. The relationship between inoculum density and disease incidence fit a logarithmic function for both cultivars. The percentage of affected trees of ‘Arbequina’ per year increased linearly (y = 0.3559x, R2 = 0.5652, and P = 0.0195) with the inoculum density in the soil, whereas this relationship was not observed for the ‘Picual’. Planting density had no effect on disease incidence for any of the two cultivars.  相似文献   
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Activation of retrotransposon is a pivotal factor in the genesis of genetic polymorphism. Retrotransposon-based molecular markers are excellent tools for detecting genetic diversity and genomic changes associated with their activity. The objective of this study was to use IRAP markers to detect integration events of retrotransposon in Opuntia, and to compare IRAP and ISSR polymorphisms. To achieve these aims, five IRAP and five ISSR markers were analyzed on three varieties and their progenies. All IRAP primers showed an increase in the percentage of polymorphism, number of total bands, and polymorphic bands in the seedlings compared to their mother plants; that is, the offspring showed 13, 24 and 27 more bands than the mother plants from Tobarito, Montesa and Copena varieties, respectively. Conversely, sexual reproduction did not proportionally affect the variation in the number of ISSR bands, and neither did polymorphisms between mother plants and their offspring. Cluster and multivariate analyses based on IRAP and ISSR data revealed a clear separation between varieties, and there was no overlapping between seedlings of different varieties. The activation of retrotransposons in seedlings of opuntia with variable frequencies was evidenced. The presence of insertion and active retrotransposons may help to undertake studies on genetic diversity and evolution of Opuntia.  相似文献   
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