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ROSSELLA AVALLONE CECILIA RUSTICHELLI ENRICO CAMPIOLI FRANCESCA MARIA PIA NOTARANGELO DANIELA BRAGHIROLI MARIO BARALDI 《Journal of Food Lipids》2009,16(3):287-296
Essential fatty acids can be helpful in the prevention of several pathologies. The bioavailability of acute supplementation of different doses of flaxseed oil was studied by analyzing the level of alpha-linolenic acid (ALA) and linoleic acid (LA) in serum and tissues (adipose, liver) of rats tested at 2, 4, 8 and 16 h after the administration. The amount of flaxseed oil administered at increasing doses corresponded to 1, 2.5 and 5 g ALA/kg of body weight. The corresponding fatty acid methyl esters obtained via direct methylation were quantified using gas chromatography/mass spectrometry. Serum ALA level increased after 1 or 2.5 g/kg. ALA was increased in both adipose and liver tissue 4 h after the administration of 1 g/kg of flaxseed oil. There was no further increase by using a higher oil dosage. LA did not change in serum at the doses used.
The bioavailability of acute supplementation of increasing doses of flaxseed oil was examined by analyzing the level of alpha-linolenic acid (ALA) (ω3) and linoleic acid (ω6) in serum and tissues (adipose, liver).These data suggest that there is a limiting step in the absorption of these fatty acids and that there is no advantage to take more than 1 g/kg of ALA supplementation. The daily use of flaxseed oil could be a good alternative in some cases to fish oil in the prevention of several pathologies. 相似文献
PRACTICAL APPLICATIONS
The bioavailability of acute supplementation of increasing doses of flaxseed oil was examined by analyzing the level of alpha-linolenic acid (ALA) (ω3) and linoleic acid (ω6) in serum and tissues (adipose, liver).These data suggest that there is a limiting step in the absorption of these fatty acids and that there is no advantage to take more than 1 g/kg of ALA supplementation. The daily use of flaxseed oil could be a good alternative in some cases to fish oil in the prevention of several pathologies. 相似文献
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RAFAEL SCAF DE MOLON MARTA MARIA ALVES PEREIRA ERICA DORIGATTI DE AVILA 《Biocell》2022,46(5):1151-1156
It has been recognized that physical and chemical properties of biomaterial surfaces mediate the quality of extracellular matrix (ECM) that may affect cell behaviors. In nature, ECM is a heterogeneous three-dimensional superstructure formed by three major components, glycosaminoglycan, glycoconjugate, and protein, that anchors cellular compartments in tissues and regulates the function and the behavior of cells. Changes in the biointerface alter the quality of ECM and morphology through cell surface receptors, which, in turn, enable it to trigger specific cell signaling and different cellular responses. In fact, a number of strategies have been used to improve the functionality of surfaces and direct cell behavior through precisely designed environments. Herein, we aimed to discuss, through a science-based viewpoint, the biomaterial surface features on cell behavior and analyze the impact of cell physical modification on dental implant development. 相似文献
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A problem consisting of the optimal design of a segmented wall on a surface having a nonlinear slope contour is considered. It is formulated as an optimal control problem and a solution procedure based on the Discrete Maximum Principle is developed. An application to a real case, which previously had been solved by a Dynamic Programming based method, is included together with some critical comments on the above-mentioned technique. 相似文献
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PATRICIA L. ALVES DE LIMA DANIEL A RIBEIRO MARINA M SUGUI ANA PAULA TEREZAN MARIA APARECIDA C DOMINGUES E R FILHO LUCIANA AZEVEDO DAISY M F SALVADORI LUCIA R RIBEIRO 《Journal of Food Biochemistry》2010,34(1):206-228
In this study, we have investigated the stability of the antigenotoxic properties of dried of Lentinula edodes (Berk.) Singer mushroom powder stored at room and at − 20C. Mice were pretreated by gavage for 15 consecutive days with 0.6 mL/day of an aqueous extract of dried L. edodes powder prepared at 60C. On day 15, the mice were intraperitoneally injected with 50 mg/kg N-ethyl-N-nitrosourea (ENU); 3 h later, peripheral blood was withdrawn from the animals and used to evaluate DNA damage using the comet assay. The mice were sacrificed 24 h after the ENU treatment and the bone marrow used to measure the frequency of micronucleated polychromatic erythrocytes. The results indicated that storage at both room temperature and at − 20C significantly reduced the antigenotoxic effects of the mushroom powder. In addition, whereas freshly dried mushroom powder was nongenotoxic, storage of the powder at − 20C resulted in genotoxic activity ( P < 0.05). Taken together, our data indicate that constituents of L. edodes powder are altered during storage, resulting in both genotoxicity and a reduction in antigenotoxicity. 相似文献
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MARIA PIA FANTI BRUNO MAIONE BIAGIO TURCHIANO 《International journal of control》2013,86(6):2523-2542
Linear positive systems are utilized in various scientific areas such as economic modelling, behavioural science, stochastic processes etc. A recent study has focused on some sufficient conditions for the controllability of these systems. A full characterization is provided of the controllability for discrete-time single-input positive systems. Necessary and sufficient conditions are derived using a digraph-theoretic approach. The main results show that strong constraints are to be imposed on the digraph associated with the pair (A, b) to ensure the controllability of the system. 相似文献
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CHARALAMPOS PROESTOS MARIA KAPSOKEFALOU MICHAEL KOMAITIS 《Journal of food quality》2008,31(3):402-414
Aromatic plants of Greek origin, Origanum dictamnus (dictamus), Eucalyptus globulus (eucalyptus), Origanum vulgare L. (oregano), Mellisa officinalis L. (balm mint) and Sideritis cretica (mountain tea) were examined for the content of phenolic substances. Reversed phase high performance liquid chromatography was used for the analysis of the plant extracts. Gas chromatography–mass spectrometry method was also used for identification of phenolic compounds after silylation. The most abundant phenolic acids were gallic acid (1.5–2.6 mg 100 g − 1 dry sample), ferulic acid (0.34–6.9 mg 100 g − 1 dry sample) and caffeic acid (1.0–13.8 mg 100 g − 1 dry sample). ( + )-Catechin and ( − )-epicatechin were the main flavonoids identified in oregano and mountain tea. Quercetin was detected only in eucalyptus and mountain tea.
Plant-derived polyphenols receive considerable interest because of their potential antioxidant and antimicrobial properties. Undoubtedly, it is very important not only to determine those properties but also to determine each and every phenol in aromatic plants both qualitatively and quantitatively. A number of analytical methods have been proposed for the separation and determination of these compounds. Most of these protocols are based on a high performance liquid chromatography technique with ultraviolet spectrophotometry. Gas chromatography–mass spectrometry after silylation of the phenolic compounds is used in this research together with the aforementioned technique as an alternative and more sensitive method to detect and understand the compositional profile of the extracts as well as the structure and functional relationship of the components in the extracts, based on MS spectra. 相似文献
PRACTICAL APPLICATIONS
Plant-derived polyphenols receive considerable interest because of their potential antioxidant and antimicrobial properties. Undoubtedly, it is very important not only to determine those properties but also to determine each and every phenol in aromatic plants both qualitatively and quantitatively. A number of analytical methods have been proposed for the separation and determination of these compounds. Most of these protocols are based on a high performance liquid chromatography technique with ultraviolet spectrophotometry. Gas chromatography–mass spectrometry after silylation of the phenolic compounds is used in this research together with the aforementioned technique as an alternative and more sensitive method to detect and understand the compositional profile of the extracts as well as the structure and functional relationship of the components in the extracts, based on MS spectra. 相似文献
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Effect of Water Activity of Milk upon Growth and Acid Production by Mixed Cultures of Streptococcus thermophilus and Lactobacillus bulgaricus 总被引:3,自引:0,他引:3
Acid production and growth rates were determined in pure cultures of Streptococcus thermophilus and Lactobacillus bulgaricus and cocci/ bacilli ratios in mixed cultures of both species, using milk with modified aw as culture medium. Maximal growth rates were always at aw lower than 0.992 for all strains whcn aw of milk was adjusted with glycerol, while maximal acid production rates were at aw 0.992-0.983. Glucose had an inhibitory effect additional to that caused by lowering aw. The cocci/bacilli ratio in mixed cultures increased as aw decreased in most cases, because of the higher susceptibility of L. bulgaricus to aw decrease. The behavior of a mixed culture could not always be predicted from data of the component strains in a pure culture, showing some kind of symbiotic compatibility between species. 相似文献