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21.
We investigated the influence of 2-furan-2-yl-1H-benzimidazole regarding vitamins A, E, C, selenium (Se), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels on rats. 2-Furan-2-yl-1H-benzimidazole was given to rats by subcutaneous injection every other day for a total of 22 injections. At the end of the experiment, Se levels were determined by using a fluorimetric method. Serum levels of vitamins A, E, C, and malondialdehyde (MDA) were determined by high-performance liquid chromatography. Glutathione peroxidase (GSH-Px) levels of erythrocytes were spectrophotometrically determined. Our experimental results showed that vitamins A, E, C, and Se levels were found generally lower than the control groups, while serum MDA level and GSH-Px activity flexibly increased, which is dependent on injection days. The observed decreases in vitamins A, E, C, and Se levels in the blood might be causally related to the increased amount of free radicals that are generated with 2-furan-2-yl-1H-benzimidazole injection. However, further investigations are needed to clarify the significance of this observation in respect with the 2-furan-2-yl-1H-benzimidazole injection. 相似文献
22.
Antioxidant and radical scavenging properties of curcumin 总被引:3,自引:0,他引:3
Curcumin (diferuoyl methane) is a phenolic compound and a major component of Curcuma longa L. In the present paper, we determined the antioxidant activity of curcumin by employing various in vitro antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH*) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, N,N-dimethyl-p-phenylenediamine dihydrochloride (DMPD) radical scavenging activity, total antioxidant activity determination by ferric thiocyanate, total reducing ability determination by the Fe(3+)-Fe(2+) transformation method, superoxide anion radical scavenging by the riboflavin/methionine/illuminate system, hydrogen peroxide scavenging and ferrous ions (Fe(2+)) chelating activities. Curcumin inhibited 97.3% lipid peroxidation of linoleic acid emulsion at 15 microg/mL concentration (20 mM). On the other hand, butylated hydroxyanisole (BHA, 123 mM), butylated hydroxytoluene (BHT, 102 mM), alpha-tocopherol (51 mM) and trolox (90 mM) as standard antioxidants indicated inhibition of 95.4, 99.7, 84.6 and 95.6% on peroxidation of linoleic acid emulsion at 45 microg/mL concentration, respectively. In addition, curcumin had an effective DPPH* scavenging, ABTS*(+) scavenging, DMPD*(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, BHA, BHT, alpha-tocopherol and trolox, were used as the reference antioxidant and radical scavenger compounds. According to the present study, curcumin can be used in the pharmacological and food industry because of these properties. 相似文献
23.
Irem Dogan Turacli Haldun Umudum Arzu Pampal Tuba Candar Lara Kavasoglu Yaren Sari 《Molecular biology reports》2018,45(3):195-201
There is a growing body of evidence about metformin being effective in cancer therapy. Despite controversies about the ways of its effectiveness, several ongoing clinical trials are evaluating the drug when used as an adjuvant or a neo-adjuvant agent. We aimed to investigate metformin’s effects on proliferation, metastasis, and hormone receptor expressions in breast cancer cell line MCF-7 incubated in two different glucose conditions. MCF-7 cells were incubated in high or low glucose media and treated with various doses of metformin. The cell viability was studied using MTT test. The Ki-67, estrogen and progesterone receptor expression were evaluated by ICC and galectin-3 expression was evaluated by ELISA or spectrophotometrically. The cell viability following consecutive metformin doses in either glucose condition for 24 and 48 h represented a significant decrease when compared to control. The proliferation detected in low glucose medium following metformin at doses < 20 mM was found significantly decreased when compared to high glucose medium at 48 h. In terms of galectin-3 levels, the increase in high glucose medium treated with metformin and the decrease in low glucose medium were found statistically significant when compared to control. Progesterone receptor staining demonstrated a significant increase in low glucose medium. Our findings represent better outcomes for cancer lines incubated in low glucose medium treated with metformin in terms of viability, receptor expression and metastatic activity, and highlight the potential benefit of metformin especially in restraining the cancer cell’s ability to cope energetic stress in low glucose conditions. 相似文献
24.
Eneda Pjetri Ria de Haas Simone de Jong Cigdem Gelegen Hugo Oppelaar Linda A. W. Verhagen Marinus J. C. Eijkemans Roger A. Adan Berend Olivier Martien J. Kas 《PloS one》2012,7(11)
Animal studies are very useful in detection of early disease indicators and in unravelling the pathophysiological processes underlying core psychiatric disorder phenotypes. Early indicators are critical for preventive and efficient treatment of progressive psychiatric disorders like anorexia nervosa. Comparable to physical hyperactivity observed in anorexia nervosa patients, in the activity-based anorexia rodent model, mice and rats express paradoxical high voluntary wheel running activity levels when food restricted. Eleven inbred mouse strains and outbred Wistar WU rats were exposed to the activity-based anorexia model in search of identifying susceptibility predictors. Body weight, food intake and wheel running activity levels of each individual mouse and rat were measured. Mouse strains and rats with high wheel running activity levels during food restriction exhibited accelerated body weight loss. Linear mixed models for repeated measures analysis showed that baseline wheel running activity levels preceding the scheduled food restriction phase strongly predicted activity-based anorexia susceptibility (mice: Beta = −0.0158 (±0.003 SE), P<0.0001; rats: Beta = −0.0242 (±0.004 SE), P<0.0001) compared to other baseline parameters. These results suggest that physical activity levels play an important role in activity-based anorexia susceptibility in different rodent species with genetically diverse background. These findings support previous retrospective studies on physical activity levels in anorexia nervosa patients and indicate that pre-morbid physical activity levels could reflect an early indicator for disease severity. 相似文献
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The paper presents a simple box model simulating the temporal variation of atmospheric 13CO2 concentration, atmospheric CO2 mixing ratio and 13C content of plant material. The model is driven by observed meteorological and measured biosphere-atmosphere CO2 exchange data. The model was calibrated and validated using measurements from a Hungarian atmospheric monitoring station.
The simulated atmospheric stable carbon isotope ratio data agreed well with the measured ratios considering both the magnitude
and the seasonal dynamics. Observed deviations between the measured and simulated δ13Cair values were systematically negative in winters, while deviations were random in sign and smaller by an order of magnitude
during periods when the vegetation was photosynthetically active. This difference, supported by a significant correlation
between the deviation and modeled fossil fuel contributions to CO2 concentration, suggests the increased contribution of 13C-depleted fossil fuel CO2 from heating and the lower boundary layer heights during winter. 相似文献
28.
K. Georgieva A. Ivanova S. Doncheva S. Petkova D. Stefanov E. Péli Z. Tuba 《Biologia Plantarum》2011,55(3):581-585
Desiccation of Xerophyta scabrida caused considerable damage of chloroplast ultrastructure together with a complete loss of chlorophyll. Upon rehydration,
the relative water content of the pale-green leaves almost reached that of the dark-green ones, however, the Chl content and
photosynthetic activity remained lower. The process of reconstitution of the photosynthetic apparatus in the re-greening leaves
was accompanied by changes in fatty acid (FA) content. The amount of the FA methyl esters was more than 2-fold higher in the
green leaves as compared to the dry ones and slightly increased after rehydration in the pale-green leaves. Among the three
main fatty acids in the leaves, oleic, palmitic and linoleic acid, the latter increased more than 3-fold during rehydration.
This acid is concentrated mainly in the glycolipids and this was an indirect indication for the restoration of the photosynthetic
apparatus. Our results showed that rehydration of X. scabrida led to a decrease of the saturated FA in parallel with an increase of the unsaturated FA, thus indicating increased membrane
permeability. The observed changes in the lipid content can be considered as a characteristic feature of X. scabrida and most probably of other poikilochlorophyllous species. 相似文献
29.
The combined use of different mass spectrometric ionization methods and MS/MS techniques provide the possibility to differentiate between stereoisomers or epimers. In this paper the mass spectral decomposition of 11alpha- and 11beta-substituted estrans was studied. Distinctive stereochemical effects have been observed in their fast atom bombardment product ion spectra. In the electron ionisation (EI) mode, the 5alpha- and 5beta-hydroxylated compounds showed significant differences in the abundance of water elimination. Mass spectrometry has proved to be an effective tool when stereoisomer steroids are compared. 相似文献
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