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101.
In contrast to current models, fluorescence resonance energy transfer measurements using a single-cell imaging assay with fluorescent forms of PER and TIM showed that these proteins bind rapidly and persist in the cytoplasm while gradually accumulating in discrete foci. After approximately 6 hours, complexes abruptly dissociated, as PER and TIM independently moved to the nucleus in a narrow time frame. The per(L) mutation delayed nuclear accumulation in vivo and in our cultured cell system, but without affecting rates of PER/TIM assembly or dissociation. This finding points to a previously unrecognized form of temporal regulation that underlies the periodicity of the circadian clock. 相似文献
102.
Pedro M. Félix José Lino Costa Bernardo R. Quintella Pedro R. Almeida Rui Monteiro Joana Santos Teresa Portela Isabel Domingos 《Fisheries Management and Ecology》2021,28(1):91-100
One of the actions that has been implemented to support the recovery of the panmictic population of European eel is stocking of waterbodies where natural recruitment is low or null. However, growth conditions of the stocked eels can vary greatly. This circumstance emphasises the importance to determine ideal habitat conditions to contribute to the success of stocking actions and, consequently, to increase the production of silver eels. This study aims to evaluate the early settlement and growth of stocked glass eels in the upper reaches of a fragmented river. Stocking was carried out, in 2014, at three sites of an inland tributary of the Mondego river basin (Central Portugal), and its monitoring was conducted during the following two years, until 2016, along with the collection of environmental and hydromorphological parameters. The results showed a successful dispersion throughout the study area. Growth varied spatially, although environmental parameters have not clearly explained this variation, but overall with high growth rates and a positive allometric growth in this early stage of stocking, suggesting a good condition of the stocked individuals. This study showed that these upper reaches of fragmented watercourses, a shared feature amongst most European rivers that are currently inaccessible for natural recruitment, may be suitable habitats for eel stocking. 相似文献
103.
104.
Sandra M Axiak‐Bechtel Kaoru Tsuruta Juliana Amorim Rebecca Donaldson Giulia Lino Allyson Honaker Farrah Monibi John Dodam Amy DeClue 《Veterinary anaesthesia and analgesia》2015,42(3):260-268
ObjectiveTramadol is a commonly used opioid analgesic in dogs, particularly in dogs with a compromised immune system. An opioid may be selected for its immunomodulatory effects. Consequently, the objective of this study was to investigate the effects of tramadol on immune system function by evaluating the effect of tramadol and o-desmethyltramadol (M1) on the function of canine leukocytes in vitro. The hypothesis was that tramadol and M1 would not alter polymorphonuclear leukocyte (PMN) phagocytosis, PMN oxidative burst, or stimulated leukocyte cytokine production capacity of tumor necrosis factor (TNF)-a, interleukin (IL)-6, and IL-10.Study designIn vitro pharmacodynamic study.AnimalsSix healthy dogs.MethodsBlood from six dogs was obtained and incubated with various concentrations of tramadol and M1. Phagocytosis and oxidative burst were assessed using flow cytometry, and lipopolysaccharide (LPS), lipoteichoic acid (LTA) and peptidoglycan (PG)-stimulated leukocyte production of TNF, IL-6, and IL-10 were measured using a canine specific multiplex assay.ResultsNo differences were detected in phagocytosis or oxidative burst with any drug concentration. Tramadol did not alter leukocyte cytokine production, however, M1 significantly blunted IL-10 production.ConclusionsTramadol and its metabolite M1 were sparing to PMN phagocytosis and oxidative burst in dogs in vitro. Tramadol did not alter leukocyte cytokine production, however, M1 blunted IL-10 production at clinically achievable concentrations suggesting that M1 may promote a proinflammatory shift.Clinical relevanceThese data suggest that tramadol has minimal effect on phagocytosis and oxidative burst, and may promote a proinflammatory shift. Therefore, tramadol may be an ideal opioid analgesic in dogs at high risk of infection. Further investigation in vivo is warranted. 相似文献
105.
Paolo Tarolli Giulia Sofia Simone Calligaro Massimo Prosdocimi Federico Preti Giancarlo Dalla Fontana 《Land Degradation \u0026amp; Development》2015,26(1):92-102
Vineyard landscapes are a relevant part of the European culture, and several authors concluded that they are the agricultural practice that causes the highest soil loss. Grape quality depends on the availability of water, and soil erosion is an important parameter dictating the vineyard sustainability; therefore, soil and water conservation measures are often implemented. Among them, the construction of terraces is the most widely used system. However, while favouring agricultural activities, terraces if not properly maintained can lead to local instabilities creating hazards for settlements and cultivations, and for the related economy. Terraced fields are also served by agricultural roads that can have deep effects on water flows triggering surface erosion. The goal of this research is to use lidar elevation data for a hydro‐geomorphological analysis of terraced vineyards. The work is divided in two parts. At first, the Relative Path Impact Index is tested in two vineyards to identify terrace‐induced and road‐induced erosions. Statistical thresholds of the Relative Path Impact Index are then defined to label the most critical areas. On the second step, using the index and the defined thresholds, we simulate different scenarios of soil conservation measures, establishing the optimal solution to reduce erosion. The results highlight the effectiveness of high‐resolution topography in the analysis of surface erosion in terraced vineyards, when the surface water flow is the main factor triggering the instabilities. The proposed analysis can help in scheduling a suitable planning to mitigate the consequences of the anthropogenic alterations induced by the terraces and agricultural roads. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
106.
Giuntini D Graziani G Lercari B Fogliano V Soldatini GF Ranieri A 《Journal of agricultural and food chemistry》2005,53(8):3174-3181
The aim of the present study was to investigate if the depletion of UV-B radiation affected the most representative carotenoids as well as the ascorbic acid content in tomato fruits, harvested at both breaker and firm red stages. To do this, three tomato genotypes, DRW 5981, HP 1, and Esperanza, were grown inside a greenhouse either covered with polyethylene transparent to UV-B or depleted of UV-B by a special covering film. The antioxidant properties of the fruits were evaluated on the water-insoluble fractions according to the ABTS method. UV-B effect on antioxidant activity was negligible in DRW and HP 1 genotypes, whereas it was detrimental in Esperanza at both ripening stages. This genotype seems to have a negligible capability of accumulating carotenoids and a great susceptibility to detrimental effects of UV-B; conversely, the DRW genotype shows high carotenoid levels under sunlight conditions and a further promotion by UV-B. On the other hand, the HP 1 mutant displays an intermediate behavior and represents the only genotype favored by UV-B with respect to ascorbic acid accumulation. 相似文献
107.
Genomic instability in mice lacking histone H2AX 总被引:1,自引:0,他引:1
Celeste A Petersen S Romanienko PJ Fernandez-Capetillo O Chen HT Sedelnikova OA Reina-San-Martin B Coppola V Meffre E Difilippantonio MJ Redon C Pilch DR Olaru A Eckhaus M Camerini-Otero RD Tessarollo L Livak F Manova K Bonner WM Nussenzweig MC Nussenzweig A 《Science (New York, N.Y.)》2002,296(5569):922-927
Higher order chromatin structure presents a barrier to the recognition and repair of DNA damage. Double-strand breaks (DSBs) induce histone H2AX phosphorylation, which is associated with the recruitment of repair factors to damaged DNA. To help clarify the physiological role of H2AX, we targeted H2AX in mice. Although H2AX is not essential for irradiation-induced cell-cycle checkpoints, H2AX-/- mice were radiation sensitive, growth retarded, and immune deficient, and mutant males were infertile. These pleiotropic phenotypes were associated with chromosomal instability, repair defects, and impaired recruitment of Nbs1, 53bp1, and Brca1, but not Rad51, to irradiation-induced foci. Thus, H2AX is critical for facilitating the assembly of specific DNA-repair complexes on damaged DNA. 相似文献
108.
109.
Mycotoxins are secondary fungal metabolites, whose presence in feed- and foodstuffs is unavoidable. Ochratoxin A (OTA) is one of the known mycotoxins with greatest public health and agro-economic significance. Several toxic effects have been ascribed following exposure, namely nephrotoxicity, as well negative impacts in the performance of farm animals, resulting in major economic implications. Of no less importance for the route of human exposure that can also embody the carry-over of OTA from feed into animal-derived products is also a concern. For all these reasons the present article updates the worldwide occurrence of OTA in different raw ingredients and finished feed destined to food-producing animals. After that a brief characterization of specie susceptibility and the major rationales is made. An historical overview of field outbreaks linked to OTA exposure in farm animals, concerning the implicated feeds, contamination levels and major clinical and productivity effects is presented. Finally a review of the major animal health and performance potential impacts of animals being reared on contaminated feed is made allied to a perspective regarding its co-occurrence with other mycotoxins, and simultaneous parasitic and bacterial infections. Ultimately, this article aims to be instructive and draw attention to a mycotoxin so often neglected and elapsed from the list of differential diagnosis in farm practice. For the unpredictability and unavoidability of occurrence, OTA will definitely be an enduring problem in animal production. 相似文献
110.
Mattivi F Vrhovsek U Malacarne G Masuero D Zulini L Stefanini M Moser C Velasco R Guella G 《Journal of agricultural and food chemistry》2011,59(10):5364-5375
In the Vitaceae, viniferins represent a relatively restricted group of trans-resveratrol oligomers with antifungal properties, thus enabling plants to cope with pathogen attack. The aim of this study was to perform isolation and structural characterization of the whole class of viniferins accumulating in the leaves of hybrid Vitis vinifera (Merzling × Teroldego) genotypes infected with Plasmopara viticola . Infected leaves of resistant plants were collected 6 days after infection, extracted with methanol, and prepurified by flash chromatography using ENV+ and Toyopearl HW 40S resins. Further fractionation using normal-phase preparative chromatography and then reversed-phase preparative chromatography allowed isolation of 14 peaks. The isolated compounds were identified using advanced mass spectrometry techniques and extensive one- and two-dimensional nuclear magnetic resonance measurements, UV, CD, optical properties, and molecular mechanic calculations. The results demonstrated the presence in infected leaves of seven dimers (six stilbenes and one stilbenoid), of which four were new in grapevine (ampelopsin D, quadrangularin A, E-ω-viniferin, and Z-ω-viniferin), four trimers (three stilbenes and one stilbenoid), of which two (Z-miyabenol C and E-cis-miyabenol C) were new in grapevine, three tetramer stilbenoids, all new in grapevine, isohopeaphenol, ampelopsin H, and a vaticanol C-like isomer. The isolation of a dimer deriving from the condensation of (+)-catechin with trans-caffeic acid also indicated that other preformed phenolics are structurally modified in tissues infected with P. viticola. 相似文献