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211.
212.
Juraj Zajac Vojtech Novohradsky Lenka Markova Viktor Brabec Jana Kasparkova 《Angewandte Chemie (International ed. in English)》2020,59(8):3329-3335
To design an anticancer drug capable of inhibiting not only the proliferation of the differentiated tumor cells but also reducing the tumorigenic capability of cancer stem cells (CSCs), the new PtIV prodrugs with axial cinnamate ligands were synthesized. We demonstrate their superior antiproliferative activity in monolayer and 3D spheroid antiproliferative activity tests using panel of cancer cell lines. An outstanding activity was found against rhabdomyosarcoma cells, one of the most problematic and poorly treatable pediatric tumors. The results also suggest that the released PtII compound inhibits antiproliferative activity of cancer cells by DNA‐damage mediated mechanism; the released cinnamic acid can trigger processes leading to differentiation, making the CSCs more sensitive to killing by the platinum part of the complex. PtIV complex with axial cinnamate ligands is the first PtIV prodrug capable of overcoming CSCs resistance and induce death in both CSCs and bulk cancer. 相似文献
213.
Sochor J Skutkova H Babula P Zitka O Cernei N Rop O Krska B Adam V Provazník I Kizek R 《Molecules (Basel, Switzerland)》2011,16(9):7428-7457
Functional foods are of interest because of their significant effects on human health, which can be connected with the presence of some biologically important compounds. In this study, we carried out complex analysis of 239 apricot cultivars (Prunus armeniaca L.) cultivated in Lednice (climatic area T4), South Moravia, Czech Republic. Almost all previously published studies have focused only on analysis of certain parameters. However, we focused on detection both primary and secondary metabolites in a selection of apricot cultivars with respect to their biological activity. The contents of thirteen biogenic alpha-L-amino acids (arginine, asparagine, isoleucine, lysine, serine, threonine, valine, leucine, phenylalanine, tryptophan, tyrosine, proline and alanine) were determined using ion exchange chromatography with UV-Vis spectrometry detection. Profile of polyphenols, measured as content of ten polyphenols with significant antioxidant properties (gallic acid, procatechinic acid, p-aminobenzoic acid, chlorogenic acid, caffeic acid, vanillin, p-coumaric acid, rutin, ferrulic acid and quercetrin), was determined by high performance liquid chromatography with spectrometric/electrochemical detection. Moreover, content of total phenolics was determined spectrophotometrically using the Folin-Ciocalteu method. Antioxidant activity was determined using five independent spectrophotometric methods: DPPH assay, DMPD method, ABTS method, FRAP and Free Radicals methods. Considering the complexity of the obtained data, they were processed and correlated using bioinformatics techniques (cluster analysis, principal component analysis). The studied apricot cultivars were clustered according to their common biochemical properties, which has not been done before. The observed similarities and differences were discussed. 相似文献
214.
Phenolic profile of edible honeysuckle berries (genus lonicera) and their biological effects 总被引:1,自引:0,他引:1
Jurikova T Rop O Mlcek J Sochor J Balla S Szekeres L Hegedusova A Hubalek J Adam V Kizek R 《Molecules (Basel, Switzerland)》2011,17(1):61-79
The current status of research on polyphenolic compounds in the berries of edible honeysuckle and their biological effects, including recommended utilization, are reviewed. The major classes of phenolic compounds in the blue berried honeysuckle are flavonols (quercetin, rutin, quercitrin) and flavanes (proanthocyanidins, catechins) and anthocyanins. Cyanidin-3-glucoside and cyanidin-3-rutinoside are considered as major anthocyanidins in edible honeysuckle berries. Such a high level of antioxidant activity in the berries of different species of the genus Lonicera is especially due to the high level of polyphenolic compounds, especially anthocyanins. These berries seem to be prospective sources of health-supporting phytochemicals that exhibit beneficial anti-adherence and chemo-protective activities, thus they may provide protection against a number of chronic conditions, e.g., cancer, diabetes mellitus, tumour growth or cardiovascular and neurodegenerative diseases. 相似文献
215.
Ondrej Zitka Sylvie Skalickova Sona Krizkova Marcela Vlkova Vojtech Adam Rene Kizek 《Chromatographia》2013,76(11-12):611-619
In this study, we optimized method for the isolation and detection of lactoferrin from human saliva using 3 mm short monolithic disc. We optimized the conditions for separation as flow rate 4 mL min?1 and ionic strength of effluent as 2 M·NaCl. We estimated limit of detection of whole method, which was hyphenated to the Bradford’s assay, down to 100 ng mL?1. The purity of the isolated fractions was verified by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and recovery of isolation was found to be 51 % using minimally processed sample of saliva. Further, we tested the optimized method on group of healthy volunteers (n = 7). We were able to distinguish between the healthy subjects and subject suffering from celiac disease, which reported at least 2.5× higher level of lactoferrin in comparison to healthy ones. The results were correlated with standard enzyme-linked immunosorbent assay (ELISA) kit with obtained correlation coefficient R 2 = 0.8446. Analysis of lactoferrin in saliva by monolithic disc and subsequent offline photometric detection is faster and cheaper method compared to ELISA commercial kit. The total analysis of one sample takes <20 min. 相似文献
216.
Masarik M Gumulec J Sztalmachova M Hlavna M Babula P Krizkova S Ryvolova M Jurajda M Sochor J Adam V Kizek R 《Electrophoresis》2011,32(24):3576-3588
Prostate cancer with altered zinc(II) cell metabolism is the second most frequently diagnosed cancer in developed countries. The alterations of zinc(II) metabolism can influence metabolism of other metal ions and can also be associated with the expression and translation of metal-binding proteins including metallothioneins. The aim of this article was to optimize immunoseparation protocol based on paramagnetic beads conjugated with protein G for the isolation of metallothionein. Isolated metallothionein was determined by differential pulse voltammetry Brdicka reaction and SDS-PAGE. Optimal conditions: antigen-binding time - 60 min, temperature - 70°C, and buffer composition and pH - acetate buffer, pH 4.3, were determined. Under the optimized conditions, lysates from 22Rv1 prostate cancer cells treated with various concentrations of cadmium(II) and copper(II) ions were analyzed. We observed strong correlation in all experimental groups and all lysate types (r>0.83 at p<0.041) between metallothionein concentration related to viability and concentration of copper(II) ions and cadmium(II) ions in medium. Moreover, the results were compared with standard sample preparation as heat treatment and SDS-PAGE analysis. 相似文献
217.
Stupavska M Jerigova M Michalka M Hasko D Szoecs V Velic D 《Journal of the American Society for Mass Spectrometry》2011,22(12):2179-2187
A technique for improving the sensitivity of high mass molecular analysis is described. Three carbon species, fullerenes,
single walled carbon nanotubes, and highly ordered pyrolytic graphite are introduced as matrices for the secondary ion mass
spectrometry analysis of cyclodextrin (C42H70O35, 1134 u). The fullerene and nanotubes are deposited as single deposition, and 10, 20, or 30 deposition films and cyclodextrin
is deposited on top. The cyclodextrin parent-like ions and two fragments were analyzed. A 30 deposition fullerene film enhanced
the intensity of cationized cyclodextrin with Na by a factor of 37. While the C6H11O5 fragment, corresponding to one glucopyranose unit, increased by a factor of 16. Although fragmentation on fullerene is not
suppressed, the intensity is twice as low as the parent-like ion. Deprotonated cyclodextrin increases by 100× and its C8H7O fragment by 10×. While the fullerene matrix enhances secondary ion emission, the nanotubes matrix film generates a basically
constant yield. Graphite gives rise to lower intensity peaks than either fullerene or nanotubes. Scanning electron microscopy
and atomic force microscopy provide images of the fullerene and nanotubes deposition films revealing flat and web structured
surfaces, respectively. A “colliding ball” model is presented to provide a plausible physical mechanism of parent-like ion
enhancement using the fullerene matrix. 相似文献