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61.
Katarína Kozics Veronika Klusová Annamária Srančíková Pavol Mučaji Darina Slameňová Ľubica Hunáková Barbara Kusznierewicz Eva Horváthová 《Food chemistry》2013
Salvia officinalis (SO) and Thymus vulgaris (TV) are medicinal plants well known for their curative powers. However, the molecular mechanisms responsible for these abilities of sage and thyme have not been fully understood yet. In this study we investigated the composition and the quantitative estimation of plant extracts, the protective effects of plant extracts against hydrogen peroxide- and 2,3-dimethoxy-1,4-naphthoquinone-induced DNA damage, and levels of enzymatic and non-enzymatic antioxidants (superoxide dismutase, glutathione peroxidase, glutathione) in human HepG2 cells. To measure antioxidative activity of plant extracts we used three assays: 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The results showed that the oxidant-induced DNA lesions were significantly reduced in cells pre-treated with the plant extracts studied. The observed DNA-protective activity could be explained by both elevation of GPx activity in cells pre-treated with SO and TV and antioxidant activity of SO and TV. 相似文献
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63.
Veronika Solteszova Åsmund Birkeland Sergej Stoppel Ivan Viola Stefan Bruckner 《Computer Graphics Forum》2017,36(1):249-262
Real‐time volume data acquisition poses substantial challenges for the traditional visualization pipeline where data enhancement is typically seen as a pre‐processing step. In the case of 4D ultrasound data, for instance, costly processing operations to reduce noise and to remove artefacts need to be executed for every frame. To enable the use of high‐quality filtering operations in such scenarios, we propose an output‐sensitive approach to the visualization of streaming volume data. Our method evaluates the potential contribution of all voxels to the final image, allowing us to skip expensive processing operations that have little or no effect on the visualization. As filtering operations modify the data values which may affect the visibility, our main contribution is a fast scheme to predict their maximum effect on the final image. Our approach prioritizes filtering of voxels with high contribution to the final visualization based on a maximal permissible error per pixel. With zero permissible error, the optimized filtering will yield a result that is identical to filtering of the entire volume. We provide a thorough technical evaluation of the approach and demonstrate it on several typical scenarios that require on‐the‐fly processing. 相似文献
64.
Wolf C Lederer K Pfragner R Schauenstein K Ingolic E Siegl V 《Journal of materials science. Materials in medicine》2007,18(6):1247-1252
Adding the natural antioxidant α-tocopherol to ultra-high molecular weight polyethylene (UHMW-PE) can remarkably delay the
oxidation of hip cups made thereof. However, α-tocopherol is likely to undergo different chemical transformations during manufacturing
and sterilization of hip cups than in human metabolism. Therefore, the biocompatibility of the putative transformation products
has to be investigated. In-vitro tests with L929 mice fibroblast-cells gave no evidence for cytotoxicity. To further ensure
the biocompatibility, in-vitro tests with human cells were carried out in this study. Two different human cell lines, one
adherent cell line, HF-SAR, and one suspension culture, GSJO, were tested on UHMW-PE-tablets (diameter: 15 mm; thickness:
2 mm; processed according to standard procedures for artificial hip-cups) with and without α-tocopherol with respect to cell
viability, proliferation and morphology by means of cell counting, WSt-1 proliferation assay and scanning electron microscopy.
Similar proliferation rates were found with both polyethylene samples. Further, we found intact morphology in light and electron
microscopy on each substrate. The morphologic characteristics of skin fibroblasts were not changed by any material. Normal
adherence and spreading of the fibroblasts was found on controls of glass, as well as on polystyrene and on stabilized and
unstabilized polyethylene. The characteristic behaviour as suspension of the GSJO cells remained unchanged. The mitochondrial
activity, as studied by WST-1 cell proliferation reagent, was identical on each substrate during the whole observation period
of 7 days.
Christian Wolf—in partial fulfillment of a Ph.D. (Dr.mont.) thesis at the University of Leoben 相似文献
65.
66.
Physical accessibility is recognised as an important driver or factor affecting landscape development in an increasing number of studies. This work uses cost-distance methods for analysis of landscape accessibility, and presents the analysis in three historical time periods focused on the effect of accessibility on landscape development in South Slovakia. First, from periods when the cultural landscape was forming, the effect of landscape accessibility on the location of settlements is given. The variables explaining the location of historical settlements are: slope steepness, accessibility to water expressed by distance to fluvial sediments and distance within 500 m from suitable soils for agriculture. The second example is from the second half of the twentieth century, when the small-scale agricultural landscape was transformed into large-scale fields suitable for industrial agriculture. Agricultural fields located on steeper slopes and closer to settlements were more likely to survive the collectivisation of agriculture. The third example shows accessibility as a factor affecting the abandonment of the remaining traditional agricultural landscapes (TAL) as a consequence of the economic and cultural changes triggered by the transition to an open market economy. The TAL located on less accessible areas are more likely affected by the abandonment. 相似文献
67.
A novel approach for carotenoid analysis has been developed. Orange essential oil and juice carotenoids were separated by means of comprehensive dual-gradient elution HPLC, using normal phase with a microbore silica column in the first dimension (first D), reversed phase with a monolithic C18 column in the second dimension (second D), and a 10-port switching valve as an interface. An on-line photodiode array detector was used in order to obtain absorption spectra. Peak identification was obtained by combining retention data with the UV-visible spectra. 相似文献
68.
Sačková V Kuliková L Kello M Uhrinová I Fedoročko P 《International journal of molecular sciences》2011,12(12):8388-8405
Several photodynamically-active substances and farnesyltransferase inhibitors are currently being investigated as promising anticancer drugs. In this study, the combined effect of hypericin (the photodynamically-active pigment from Hypericum perforatum) and selective farnesyltransferase inhibitor manumycin (manumycin A; the selective farnesyltransferase inhibitor from Streptomyces parvulus) on HT-29 adenocarcinoma cells was examined. We found that the combination treatment of cells with photoactivated hypericin and manumycin resulted in enhanced antiproliferative and apoptotic response compared to the effect of single treatments. This was associated with increased suppression of clonogenic growth, S phase cell cycle arrest, elevated caspase-3/7 activity and time-dependent total cleavage of procaspase-3 and lamin B, cleavage of p21Bax into p18Bax and massive PARP cleavage. Moreover, we found that the apoptosis-inducing factor is implicated in signaling events triggered by photoactivated hypericin. Our results showed the relocalization of apoptosis-inducing factor (AIF) to the nuclei after hypericin treatment. In addition, we discovered that not only manumycin but also photoactivated hypericin induced the reduction of total Ras protein level. Manumycin decreased the amount of farnesylated Ras, and the combination treatment decreased the amount of both farnesylated and non-farnesylated Ras protein more dramatically. The present findings indicate that the inhibition of Ras processing may be the determining factor for enhancing the antiproliferative and apoptotic effects of combination treatment on HT-29 cells. 相似文献
69.
Multiple indices of body condition reveal no negative effect of urbanization in adult house sparrows 总被引:1,自引:0,他引:1
As urbanized areas expand and develop throughout the world, the importance of understanding their effects on wildlife increases. Living in cities may be stressful for animals but may also provide benefits at the same time, and the sum of these effects should manifest in the body condition of individuals. Studies addressing this phenomenon tend to evaluate one or few indices of body condition, each of which may be subject to various confounding effects and seasonal changes. In this study we used multiple approaches to assess the effects of urbanization on adult body condition in house sparrows (Passer domesticus), a passerine undergoing population declines in urban habitats. In line with earlier studies, we found that sparrows in more urbanized habitats have reduced body mass. However, birds had similar scaled mass index (body mass corrected for body size) along the urbanization gradient at all times of the year, contradicting the previous result on type-1 regression residuals. In the non-breeding season, urban and rural birds had similar levels of corticosterone, hematocrit, and heterophil:lymphocyte ratio. In the molting season, hematocrit indicated better condition in rural birds whereas H:L ratio showed the opposite; however, these trends were not consistent between age groups. Two condition-dependent plumage traits, male bib size and wing bar size, showed no systematic variation along the gradient of urbanization. These results suggest that the environmental conditions experienced by adult house sparrows are not more stressful in more urbanized habitats, and they also highlight the importance of considering multiple indices of body condition. 相似文献
70.
Gtz Hüsken Stephan Pirskawetz Dietmar Meinel Veronika Babski Hans‐Carsten Kühne 《Bautechnik》2016,93(10):711-716
Methods for analyzing the fracture behavior of high‐strength steel fiber‐reinforced concretes High‐strength and ultra‐high strength fiber‐reinforced concretes are most suitable for applications with extreme mechanical loads. These extreme conditions require a ductile behavior under tensile loading, which is obtained solely by the addition of steel fibers and their working mechanism. Profound know ledge on the working mechanism of the steel fibers is necessary for optimizing this material. Usually, this knowledge is obtained by means of classical measuring techniques of destructive tests. Adopting measuring techniques from non‐destructive material testing helps to analyze and to identify the different stages of the fracture mechanism of high‐strength and ultra‐high strength fiber‐reinforced concretes in detail. The application of different non‐destructive measuring techniques is shown exemplary on tensile tests conducted on an ultra‐high strength fiber‐reinforced concrete and its applicability for analyzing the fracture behavior is discussed. The main focus is on the characterization of the relevant failure modes under tensile loading by the different measuring techniques and the comparison with classical measuring techniques (e. g. extensometer). The tensile tests have been analyzed by optical deformation measurements using digital image correlation (DIC), acoustic emission analysis (AE), and 3D computed tomography (CT). 相似文献