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101.
Jasna Huremović Milena Horvat Jože Kotnik David Kocman Suzana Žižek Sergio Ribeiro Guevara 《Analytical letters》2017,50(6):1049-1064
Tuzla is among the most polluted cities of Bosnia and Herzegovina. The main source of pollution in the area is soil heavily contaminated by mercury released from a former chloralkali plant. This paper is focused on the characterization of mercury contaminated soil and air surrounding the chloralkali plant. In soil, the mobility and transformation of mercury were investigated by sequential extraction, while the methylation and reduction potentials were determined by the use of a radioactive tracer. Mercury emission from soil was determined by laboratory and by flux chamber measurements in the field. In addition, mercury concentrations in air were estimated by the analysis of air and the transplanted lichen Hypogymnia physodes. Mercury in soils in the vicinity of the chloralkali plant exceeded the background value by a factor of more than 3000. The fractionation of mercury in surface soil by sequential extraction showed that the mercury in soil was primarily bound to organic matter and a fraction containing elemental mercury and mercury (I) chloride is also significant. The obtained methylation and reduction potentials are low. The mercury flux from soil was estimated by two approaches. Fluxes of up to 8000?ng/m2/day were measured at the most polluted site; evaporation from soil was shown to be the primary source of elevated mercury in air. Air concentration mapping also revealed other sources of mercury; the most likely is the 715 MW coal power plant in the vicinity of former chloralkali facility. 相似文献
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Petra Hoffmann Marcel Hülsewig Sevim Duvar Holger Ziehr Michael Mormann Jasna Peter‐Katalinić Alexander W. Friedrich Helge Karch Johannes Müthing 《Rapid communications in mass spectrometry : RCM》2010,24(15):2295-2304
Shiga toxin (Stx, synonymous to verotoxin, VT) binds with high and low affinity to the globo‐series neutral glycosphingolipids (GSLs), globotriaosylceramide (Gb3Cer or Galα4Galβ4Glcβ1Cer, also known as CD77) and globotetraosylceramide (Gb4Cer or GalNAcβ3Galα4Galβ4Glcβ1Cer), respectively, which represent the targets of Stxs on many different cell types. B‐cell‐derived Raji cells and THP‐1 cells of monocytic origin are widely used for the investigation of Stx‐mediated cellular response, because Stx is known to cause cell death in both cell lines. Despite their functional importance, the Stx receptors of Raji and THP‐1 cells have so far not been investigated. This prompted us to explore the structures of their GSL receptors in detail by means of nanoelectrospray ionization quadrupole time‐of‐flight mass spectrometry (nanoESI‐QTOF‐MS) with collision‐induced dissociation (CID) in conjunction with Stx1 as well as anti‐Gb3Cer and anti‐Gb4Cer antibodies. Using the combination of a thin‐layer chromatography (TLC) overlay assay and MS1 and MS2 analysis we identified Gb3Cer (d18:1, C24:1/C24:0) as the prevalent Stx1‐receptor accompanied by less abundant Gb3Cer (d18:1, C16:0) in the neutral GSL fraction of Raji cells. The same Gb3Cer species but with almost equal proportions of the C24:1/C24:0 and C16:0 variants were found in THP‐1 cells. In addition, unusual hydroxylated Gb3Cer (d18:1, C24:1/C24:0) and Gb3Cer (d18:1, C26:1) could be identified in trace quantities in both cell lines. As the most obvious difference between Raji and THP‐1 cells we observed the expression of Gb4Cer in THP‐1 cells, whereas Raji cells failed to express this elongation product of Gb3Cer. Both short‐ and long‐chain fatty acid carrying Gb4Cer (d18:1, C16:0) and Gb4Cer (d18:1, C24:1/C24:0), respectively, were the prevalent Gb4Cer variants. This first report on the differential expression of Gb3Cer and Gb4Cer and their structural diversity in lymphoid and myeloid cell lines supports the hypothesis that such heterogeneities might play a functional role in the molecular assembly of GSLs in membrane organization and cellular signaling of Stx‐susceptible cells. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Vesna Tumbas Šaponjac Dragana Četojević-Simin Gordana Ćetković Jasna Čanadanović-Brunet Sonja Djilas Anamarija Mandić Aleksandra Tepić 《Central European Journal of Chemistry》2014,12(3):377-385
Ground spice paprika was extracted with hexane, by conventional Soxhlet procedure (SX oleoresin), and with supercritical carbon dioxide at three different pressures — 20, 30 and 40 MPa (SF20, SF30 and SF40 oleoresins). The effect of extraction method and conditions on the colour intesity of paprika oleoresins, content of α-tocopherol, as well as antioxidant and antiproliferative activity was examined. Hexane showed highest selectivity for paprika pigments (886.02 ASTA), while α-tocopherol showed highest solubility (3846.9 mg kg?1) in supercritical carbon dioxide at 20 MPa. All paprika oleoresins exhibited good superoxide anion radical scavenging activity SF30 being the best superoxide anion radical scavenger. Cell growth activity was evaluated in vitro in human cell lines:cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT-29). The highest antiproliferative activity was exhibited by SX in MCF7 cell line (IC50=14.28 mg mL?1). Extract SF40 produced significant and selective antiproliferative action towards HeLa cell line. These results suggest that paprika oleoresins, due to high antiradical and tumor cell-inhibiting activity, can be regarded as functional food ingredients. 相似文献
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The targeted solid-phase synthesis of 3-hydroxyquinolin-4(1H)-one derivatives is described. Primary and secondary amines, 3-amino-4-(methoxycarbonyl)benzoic acid and 2-bromo-1-(4-chloro-3-nitrophenyl)ethanone were used as starting materials. The structures of the final compounds were designed in accordance with previous information obtained from structure–activity relationship studies of similar cytotoxic derivatives. Representative prepared compounds were subjected to in vitro screening of cytotoxic activity against various cancer cell lines; the results obtained are discussed. Fluorescence properties of selected compounds were also studied to compare the data with those obtained in analogous derivatives. 相似文献
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Identification and structural characterization of novel O‐ and N‐glycoforms in the urine of a Schindler disease patient by Orbitrap mass spectrometry 下载免费PDF全文
Mirela Sarbu Cristian V. A. Munteanu Liana Dehelean Andrei J. Petrescu Jasna Peter‐Katalinic Alina D. Zamfir 《Journal of mass spectrometry : JMS》2015,50(9):1044-1056
Schindler disease is an inherited metabolic disorder caused by the deficient activity of α‐N‐acetylgalactosaminidase enzyme. An accurate diagnosis requires, besides clinical examination, complex and costly biochemical and molecular genetic tests. In the last years, mass spectrometry (MS) based on nanofluidics and high‐resolution instruments has become a successful alternative for disease diagnosis based on the investigation of O‐glycopeptides in patient urine. A complex mixture of glycoforms extracted from the urine of a 3‐year‐old patient was investigated by Orbitrap MS equipped with Nanospray Flex Ion Source in the negative ion mode. For structural characterization of several molecular species, collision‐induced dissociation MS2–MS3 was carried out using collision energy values within 20–60 eV range. By our approach, 39 novel species associated to this condition were identified, among which O‐glycopeptides, free O‐glycans and one structure corresponding to an N‐glycan never characterized in the context of Schindler disease. The experiments conducted at a resolution of 60 000 allowed the discrimination and identification of a total number of 69 different species with an average mass accuracy of 9.87 ppm, an in‐run reproducibility of almost 100%, an experiment‐to‐experiment and day‐to‐day reproducibility of about 95%. This study brings contributions in the diagnosis of Schindler disease through the elucidation of potential biomarker species in urine. Our multistage MS results completed with 39 new glycoforms the inventory of potential biomarker structures associated to Schindler disease. For the first time, an N‐glycan was identified and structurally characterized in Schindler patient urine, which opens new research directions in the field. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Marina Krvavica Dario Lasi Jasenka Gajdo Kljusuri Jelena ugum piro Janovi Sran Milovac Jasna Bonir 《Molecules (Basel, Switzerland)》2021,26(14)
Chemical characteristics of raw and processed Istarski pršut (PDO) produced from two different pig genotypes were studied with special emphasis on amino and fatty acid composition and factors of lipid stability. Raw hams of Large White (LW)xLandrace (L), and (LWxL)xDuroc (D) pig genotypes were used in the study (20 hams of each genotype). All left raw hams from each carcass were processed in accordance with the PDO specification of Istarski pršut, and other half (the right ones) of LWxL)xD genotype were used for analyses of raw hams (fresh muscles). Istarski pršut was evaluated on the basis of the chemical parameters of the raw and matured lean ham. The process of dry curing significantly influenced the chemical properties of Istarski pršut. Despite the higher content of intramuscular fat and polyunsaturated fatty acids, the fat of (LWxL)xD ham was much more resistant to hydrolysis and oxidation, suggesting that fatty acid profile and other factors, also play a significant role. Significant differences between pig genotypes in the amino acid and fatty acid profiles were found. The analyzed Istarski pršut may be distinguished by prints of multivariate chemometric statistical analysis, based on their amino acid and fatty acid compositions. 相似文献
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