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11.
Cytoprotection by neutral fraction of tannat red wine against oxidative stress-induced cell death 总被引:1,自引:0,他引:1
Echeverry C Blasina F Arredondo F Ferreira M Abin-Carriquiry JA Vasquez L Aspillaga AA Diez MS Leighton F Dajas F 《Journal of agricultural and food chemistry》2004,52(24):7395-7399
Some of the beneficial effects of the Mediterranean diet on human pathologies have been attributed to red wine polyphenols. It has been postulated that the antioxidant activity of the latter would be also responsible for the cytoprotective capacity of red wine that has been reported in a few papers. Nevertheless, red wine shows a complex composition, and the active fraction is not known yet. In this context, the protective capacity of total lyophilized extracts of red wine and anthocyanin, neutral, or acidic fractions, was explored in PC12 cells in culture after a hydrogen peroxide insult. Although all fractions showed high antioxidant activity, only the neutral fraction was cytoprotective. The analysis of this active fraction showed that it was rich in the aglycons quercetin and myricetin as well as the glycosides of kaempferol, isorhamnetin, epicatechin, and catechin, some of which are known to be cytoprotective. This is the first paper to reveal the active fraction of total wine responsible of its cytoprotection. 相似文献
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Gaspar Soria Miguel F. Lavín Iván Martínez‐Tovar Alberto Macías‐Duarte 《Aquaculture Research》2013,44(9):1383-1398
We evaluated recruitment of larvae of catarina scallop, Argopecten ventricosus, in the area of Puerto Peñasco, NE Gulf of California. We moored artificial collectors in six sites from June 2007 to August 2008 and replaced them every 2 months. We used monthly (July 2002–September 2011) sea surface temperature (SST, °C) and surface chlorophyll‐a concentration (SSChl, mg m?3) Aqua/MODIS satellite data to describe seasonal environmental behaviour study area. Also, we recorded bottom temperature at each site every 4 h, and every 2 months measured sea surface salinity, temperature and dissolved oxygen. We used a repeated measures anova to evaluate differences in the number of recruited spat between main factors, and analysed the presence of multimodal spat shell size frequency distributions. Overall, spat recruitment was negatively correlated with seawater temperature and showed higher spat recruitment abundances throughout winter, which is the season with the highest surface chlorophyll a concentration. We estimated multimodal shell size frequency distributions characterized by more than one modal size. The natural collection of A. ventricosus spat on artificial collectors in the area can be successfully performed over a protracted period (November–December to May–June). Our results extend the area where collection of A. ventricosus spat can be successful. 相似文献
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Rosa María Arias Gabriela Heredia-Abarca Vinicio J. Sosa Luis Ernesto Fuentes-Ramírez 《Agroforestry Systems》2012,85(1):179-193
We evaluate the arbuscular mycorrhizal fungi (AMF) community as measured by spores in different coffee production systems (at the depth of 0?C15?cm). In addition, we analyze the similarities between the AMF communities in coffee production systems and those that occur in a tropical montane cloud forest patch in order to evaluate the capacity of coffee production systems to preserve the native AMF community. We carried out four samplings in five coffee production systems representative of a vegetation structure gradient, and in a forest. From 120 soil samples, 33 morphospecies were detected. In all the sites, the dominant morphospecies were Glomus clarum and Glomus sp. 3. We found no significant difference in AMF spore richness between sites. Diversity was similar in most of the coffee production systems. Significant differences were only detected in spore abundance; during the dry season the forest, shaded traditional rustic system and shaded simple system presented the highest spore abundance. With the exception of one species exclusive to the forest, the coffee production systems all share the same AMF species as the forest. The coffee production systems with the greatest similarity to cloud forest were the shaded traditional rustic system and the shaded simple system. It is suggested that control of weeds and fertilization could be important factors influencing the composition and abundance of AMF spores in coffee production systems. 相似文献
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Aline F. S. Carvalho Monica R. Ferreira Machado Estefnia S. Andrade Luis D. S. Murgas Mrcio G. Zangeronimo Thiago C. Barros Fernanda G. Paula 《Journal of the World Aquaculture Society》2014,45(1):75-81
The aim was to evaluate the effect of different concentrations of caffeine added in activating solution over sperm motility in fresh and thawed semen of pacu, Piaractus mesopotamicus, and curimba, Prochilodus lineatus. The activating solutions were prepared with sodium bicarbonate solution of 0.76% (NaHCO3) and caffeine was added at concentrations of 2.5, 5.0, 10.0, and 20.0 mM. As control, a solution of NaHCO3 0.76 without caffeine was used. Eight males of pacu and 20 males of curimba were used. Aliquots of 200 μL of semen were diluted in 800 μL extender solution (DMSO 10% and BTS 5%), placed in 0.5 mL straws and cryopreserved for 7 d in a liquid nitrogen tank. There was a linear increase in sperm motility for fresh semen of pacu, and for curimba fresh and thawed semen (P < 0.05), due to the increase in the concentration of caffeine. There was a quadratic response for duration of motility for thawed semen of pacu and for fresh semen of curimba (P < 0.05), respectively. These results indicate that addition of caffeine in the activator solution can improve sperm motility parameters, however, is dependent on the species and concentration used. 相似文献
17.
Rosalinda Mendoza-Villarreal Alberto Sandoval-Rangel Valentín Robledo-Torres Adalberto Benavides-Mendoza 《Journal of plant nutrition》2015,38(1):73-82
Nitrogen (N) by form of nutrition, ammonium (NH4+) or nitrate (NO3?), affects metabolic and physiological processes of plants. In general, a high proportion of N in NH4+ form results in poor growth. Nonetheless, a number of species exhibit optimum growth when high levels of NH4+ are provided. In the present study, lisianthus [Eustoma grandiflorum (Raf.) Shinn] was grown in rockwool cultures and irrigated with nutrient solutions containing 15 mM N with varying proportions of NH4+ and NO3?. The results showed that an increase in NH4+-N form increased plant height, number of flowers and leaves, leaf area, and shoot, stem, and leaf dry weight. The proportion of NH4+ also affected leaf concentration of phosphorus, potassium (K), calcium (Ca), and magnesium (Mg), although leaf N concentration was unaffected. Potassium leaf concentration was higher when a low proportion of NH4+ was supplemented in the nutrient solution; however, plants exhibited a decrease in leaf K concentration and a decrease in leaf Ca as the proportion of NH4+-N increased. Shoot dry weight was higher with low leaf K whereas high leaf Ca was associated with high shoot dry weight. Net photosynthesis rate was higher in plants irrigated with solutions containing 75% of total N in NH4+ form than in those irrigated with solutions of 0 or 25%. The results suggest that lisianthus can tolerate high levels of NH4+, probably associated with a higher assimilation of Ca. 相似文献
18.
Luis Alfonso Gracia-Calvo María Esther DuránMaría Martín-Cuervo DVM MS Verónica VieítezJoaquín Jiménez DVM PhD Luis Javier Ezquerra DVM PhD dip ECVS 《Journal of Equine Veterinary Science》2014
A 13-year-old Lusitano stallion was referred to our institution with a history of severe hematuria for 8.5 months. The origin of the hematuria was determined to be the left kidney. The diagnostic workup failed to identify obstructive, infectious, or neoplastic conditions. The history and ultrasonographic examination suggested a chronic condition. The stallion was subjected to left nephrectomy because of the persistent hematuria and anemia. A histopathological examination detected lesions, which were compatible with chronic nephritis and vascular renal hypertension. It is hypothesized that changes in the normal parenchymal architecture produced a vascular aberration that led to renal hypertension, with subsequent blood extravasation and hematuria. The horse recovered completely after nephrectomy. 相似文献
19.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
20.
巴西是世界上最大的谷物生产国和禽、猪肉的出口国之一。在霉菌毒素问题解决上,他们又为全世界做了表率。相比而言,在目前资源相对短缺的情况下,如何对原料加以善用,值得我们深思。 相似文献