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1.
Jiménez-Escrig A Dragsted LO Daneshvar B Pulido R Saura-Calixto F 《Journal of agricultural and food chemistry》2003,51(18):5540-5545
Artichoke (Cynara scolymus L.), an edible vegetable from the Mediterranean area, is a good source of natural antioxidants such as vitamin C, hydroxycinnamic acids, and flavones. The antioxidant activity of aqueous-organic extracts of artichoke were determined using three methods: (a) free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH(*)) scavenging, (b) ferric-reducing antioxidant power (FRAP), and (c) inhibition of copper(II)-catalyzed in vitro human low-density lipoprotein (LDL) oxidation. In addition, the present study was performed to investigate the ability of the edible portion of artichoke to alter in vivo antioxidative defense in male rats using selected biomarkers of antioxidant status. One gram (dry matter) had a DPPH(*) activity and a FRAP value in vitro equivalent to those of 29.2 and 62.6 mg of vitamin C and to those of 77.9 and 159 mg of vitamin E, respectively. Artichoke extracts showed good efficiency in the inhibition in vitro of LDL oxidation. Neither ferric-reducing ability nor 2,2'-azinobis(3-ethylbenzothiazolin-6-sulfonate) radical scavenging activity was modified in the plasma of the artichoke group with respect to the control group. Among different antioxidant enzymes measured (superoxide dismutase, gluthatione peroxidase, gluthatione reductase, and catalase) in erythrocytes, only gluthatione peroxidase activity was elevated in the artichoke group compared to the control group. 2-Aminoadipic semialdehyde, a protein oxidation biomarker, was decreased in plasma proteins and hemoglobin in the artichoke-fed group versus the control group. In conclusion, the in vitro protective activity of artichoke was confirmed in a rat model. 相似文献
2.
Romero-Bastida CA Flores-Huicochea E Martin-Polo MO Velazquez G Torres JA 《Journal of agricultural and food chemistry》2004,52(8):2230-2235
The effect of moisture content and film composition on biodegradability is the focus of this study. Flexible films were first characterized for the effect on water sorption isotherms of relative humidity, temperature, zein content, and the addition of the plasticizers stearic acid, poly(ethylene glycol), or etoxylated ricine oil. Zein/ethylcellulose (EC) mixture films had a behavior between that for pure zein and EC films, which had the lowest water sorption. For films with plasticizer, the lowest water sorption at 25 degrees C was observed for those with stearic acid. Biodegradability of zein/EC films, evaluated using bacterial cultures selected for their zein proteolytic activity and isolated from a local solid waste landfill and a lagoon, showed no plasticizer effect even though its effect on moisture content was significant. Large differences were observed at different film zein concentration with the highest biodegradability for 100% zein. However, biodegradability did not mimic the water sorption behavior of zein/EC mixture films. 相似文献
3.
Mark K. Asplen Gianfranco Anfora Antonio Biondi Deuk-Soo Choi Dong Chu Kent M. Daane Patricia Gibert Andrew P. Gutierrez Kim A. Hoelmer William D. Hutchison Rufus Isaacs Zhi-Lin Jiang Zsolt Kárpáti Masahito T. Kimura Marta Pascual Christopher R. Philips Christophe Plantamp Luigi Ponti Gábor Vétek Heidrun Vogt Vaughn M. Walton Yi Yu Lucia Zappalà Nicolas Desneux 《Journal of pest science》2015,88(3):469-494
4.
Marcos Antonio Camacho da Silva William Natale Renato de Mello Prado Márcio Koiti Chiba 《Journal of plant nutrition》2013,36(4):694-702
ABSTRACT Citrus cultures have a fundamental importance to the Brazilian economy; certain aspects such as plant nutrition, yield, and fruit quality are vital for the citrus industry sustainability. The present study evaluated the nutritional status of manganese in adult Pear orange trees using different lime rates topically applied to the soil. The direct evaluation of lime rates effects on leaf manganese (Mn) levels revealed a decrease of the nutrient correlated to its increased, as well as passage of time between application and measurement. Foliar sampling 30 months after surface lime application evidenced a high correlation of foliar manganese levels with soil base saturation of 10–20 cm. Leaf manganese levels which showed a great probability of high productivity were between 33 and 70 mg kg?1. 相似文献
5.
Effects of Application of Organic and Inorganic Wastes for Restoration of Sulphur-Mine Soil 总被引:1,自引:0,他引:1
Raquel Melgar-Ramírez Verónica González Juan Antonio Sánchez Inés García 《Water, air, and soil pollution》2012,223(9):6123-6131
In situ remediation with waste material is an inexpensive method to reduce contaminant availability in polluted soil. The experiments were done to investigate the effects of possible in situ application of two different amendments: inorganic material (marble sludge) and organic material (horticultural waste compost) on chemical and biological properties of abandoned metalliferous mine wastes. The results show that the application of inorganic material raises the pH above neutrality and the combination of inorganic and organic material would produce the highest ratio of biological activity. The reductions of available Zn, Pb and As in lime, organic and lime/organic amendments were favoured by incubation time. However, available Cd content increased after 275?days of incubation, except the treatment with inorganic amendment. This work denoted that the application of lime with organic amendments has a better effect than the lime alone because the addition of both amendments improves both soil chemical and biological properties. 相似文献
6.
Antonio Paoli Tatiana Moro Gerardo Bosco Antonino Bianco Keith A. Grimaldi Enrico Camporesi Devanand Mangar 《Marine drugs》2015,13(2):996-1009
Background: the ketogenic diet (KD) has become a widely used nutritional approach for weight loss. Some of the KD’s positive effects on metabolism and cardiovascular risk factors are similar to those seen after n-3 polyunsaturated fatty acids (ω-3) supplementation. We hypothesized that a ketogenic Mediterranean diet with phytoextracts combined with ω-3 supplementation may have increased positive effects on cardiovascular risk factors and inflammation. Methods: We analyzed 34 male overweight subjects; aged between 25 and 65 years who were overall healthy apart from overweight. The subjects followed a ketogenic diet protocol for four weeks; with (KDO3) or without (KD) ω-3 supplementation. Results: All subjects experienced a significant loss of body weight and body fat and there was no significant differences between treatment (body weight: KD—4.7 kg, KDO3—4.03 kg, body fat KD—5.41 kg, KDO3—5.86 kg). There were also significant decreases in total cholesterol, LDL-c, and glucose levels. Triglycerides and insulin levels decreased more in KDO3 vs. KD subjects, with a significant difference. All the investigated inflammatory cytokines (IL-1β, IL-6, TNF-α) decreased significantly in KDO3 subjects whilst only TNF-α showed a significant decrease in KD subjects over the 12 month study period. No significant changes were observed in anti-inflammatory cytokines (IL-10 and IL-1Ra), creatinine, urea and uric acid. Adiponectin increased significantly only in the KDO3 group. Conclusions: ω-3 supplementation improved the positive effects of a ketogenic Mediterranean diet with phytoextracts on some cardiovascular/metabolic risk factors and inflammatory state. 相似文献
7.
Tiziana La Rosa Simone Mirto Antonio Mazzola Teresa Luciana Maugeri 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):153-167
We studied the impact of organic loads due to the biodeposition of a fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and benthic microbial community were investigated from July 1997 to February 1998 on monthly basis at two stations: one was located under the fish farm, while the second was about 1 km away, and served as a reference site. The presence of the cage induced rapid changes in the benthic conditions: the sediments were rapidly (after 6 weeks) reduced. A significant accumulation of biopolymeric carbon was observed beneath the cage both 2 weeks after the initial cage deployment, on non-impacted sediments, and 5–7 months after, and appeared to be related to the fish farm production cycle. The density of microbial communities beneath the fish farm increased only during the first month of farming activity (July) and partially 7 months after cage disposal (i.e. in January), when there was a significant sediment organic enrichment. Additional evidence of rapid impact of the fish farm on the benthic bacterial communities is provided by the increase in the numbers of autofluorescent microbial cells. The photosynthetic eukaryotic cells displayed a highly reduced contribution to total autofluorescent microbial density, indicating that their decrease is related with biopolymeric carbon accumulation, and probably was due also to “shadow effect” induced by suspended material, coming from the fish farm, on the environment below. We propose here, to apply the ratio of culturable heterotrophic bacteria to microbial direct counts (CFU/MDC) to detect fish farm impact. In cage sediments, organic enrichment and the consequent modification of the characteristics of the benthic environment, determined an increase in aerobic heterotrophic bacteria and vibrio density indicating that they are efficient colonizers of organic-rich sediments. Densities of Escherichia coli and Enterococci were not significantly higher than in the reference site, and are likely of terrestrial origin. Thus they cannot be used as specific indicators of fish farm impact. 相似文献
8.
A neutralizing antibody selected from plasma cells that binds to group 1 and group 2 influenza A hemagglutinins 总被引:2,自引:0,他引:2
Corti D Voss J Gamblin SJ Codoni G Macagno A Jarrossay D Vachieri SG Pinna D Minola A Vanzetta F Silacci C Fernandez-Rodriguez BM Agatic G Bianchi S Giacchetto-Sasselli I Calder L Sallusto F Collins P Haire LF Temperton N Langedijk JP Skehel JJ Lanzavecchia A 《Science (New York, N.Y.)》2011,333(6044):850-856
The isolation of broadly neutralizing antibodies against influenza A viruses has been a long-sought goal for therapeutic approaches and vaccine design. Using a single-cell culture method for screening large numbers of human plasma cells, we isolated a neutralizing monoclonal antibody that recognized the hemagglutinin (HA) glycoprotein of all 16 subtypes and neutralized both group 1 and group 2 influenza A viruses. Passive transfer of this antibody conferred protection to mice and ferrets. Complexes with HAs from the group 1 H1 and the group 2 H3 subtypes analyzed by x-ray crystallography showed that the antibody bound to a conserved epitope in the F subdomain. This antibody may be used for passive protection and to inform vaccine design because of its broad specificity and neutralization potency. 相似文献
9.
We compared the water-use characteristics of co-occurring mature Quercus cerris L. and Quercus pubescens Willd. trees growing in resource-limited (mainly water) hilly habitats in Tuscany, Italy. The species differed in their distribution along soil water gradients and in their access to, and use of, water, even though the study year was wetter than average, though with a summer drought. Compared with Q. cerris, Q. pubescens had greater access to soil water (less negative predawn water potentials) and a more conservative water-use strategy based on its relatively low stomatal conductance, high instantaneous water-use efficiency, less negative midday water potential and high soil-to-leaf hydraulic conductance. Quercus cerris had less conservative water-use characteristics than Q. pubescens, exhibiting relatively high stomatal conductance, low instantaneous water-use efficiency, more negative midday water potentials and low soil-to-leaf hydraulic conductance; however, Q. cerris had higher photosynthetic rates than Q. pubescens. Photosynthesis and stomatal conductance were positively correlated in both species. Although a strong correlation between ring widths and precipitation patterns was not found, some dry periods influenced ring-width growth. Quercus pubescens has always grown faster than Q. cerris, probably because of more efficient water use, although stand dynamics (driven by exogenous disturbance factors, including coppicing, browsing and competition) cannot be excluded. Ring-width variability, as well as tree-ring growth in dry years, which should be unaffected by stand dynamics, were higher in Q. pubescens than in Q. cerris. Moreover, Q. pubescens recovered completely after the drought in the seventies, even showing higher tree-ring growth than in the recent past, whereas Q. cerris showed a minor growth decline followed by a recovery to values comparable with those observed before the 1970s drought. Beginning in the early eighties, tree-ring growth decreased in both species, though Q. pubescens showed consistently higher values than Q. cerris. These differences can be explained by differences in water-use efficiency. Despite differences between the species in water use and water status, the results are consistent with the interpretation that both are drought tolerant, but that Q. pubescens is at an advantage on xeric ridges because of its greater ability to access soil water and use it more conservatively compared with Q. cerris. 相似文献
10.
Pastalkova E Serrano P Pinkhasova D Wallace E Fenton AA Sacktor TC 《Science (New York, N.Y.)》2006,313(5790):1141-1144
Analogous to learning and memory storage, long-term potentiation (LTP) is divided into induction and maintenance phases. Testing the hypothesis that the mechanism of LTP maintenance stores information requires reversing this mechanism in vivo and finding out whether long-term stored information is lost. This was not previously possible. Recently however, persistent phosphorylation by the atypical protein kinase C isoform, protein kinase Mzeta (PKMz), has been found to maintain late LTP in hippocampal slices. Here we show that a cell-permeable PKMz inhibitor, injected in the rat hippocampus, both reverses LTP maintenance in vivo and produces persistent loss of 1-day-old spatial information. Thus, the mechanism maintaining LTP sustains spatial memory. 相似文献