Gangliosides serve as antitumor therapy targets and aberrations in their composition strongly correlate with tumor growth and invasiveness. Anaplastic ganglioglioma is a rare, poorly characterized, malignant neuronal–glial tumor type. We present the first comparative characterization of ganglioside composition in anaplastic ganglioglioma vs. peritumoral and healthy brain tissues by combining mass spectrometry and thin-layer chromatography. Anaplastic ganglioglioma ganglioside composition was highly distinguishable from both peritumoral and healthy tissue despite having five to six times lower total content. Ten out of twelve MS-identified ganglioside classes, defined by unique glycan residues, were represented by a large number and considerable abundance of individual species with different fatty acid residues (C16–C24) in ceramide portions. The major structurally identified class was tumor-associated GD3 (>50%) with 11 species; GD3 (d18:1/24:0) being the most abundant. The dominant sphingoid base residue in ganglioside ceramides was sphingosine (d18:1), followed by eicosasphingosine (d20:1). The peritumoral tissue ganglioside composition was estimated as normal. Specific ganglioside composition and large variability of ganglioside ceramide structures determined in anaplastic ganglioglioma demonstrate realistic ganglioside expression patterns and correspond to the profile of high-grade malignancy brain tumors.
Metals play crucial physiological roles, but they can also cause irreparable toxic effects through binding to important cellular biomolecules in aquatic organisms. The aim of this study was to determine the exact molecular masses and to identify several selected metal-binding biomolecules in hepatic and gill cytosols of Vardar chub (Squalius vardarensis Karaman, 1928). Methods applied for the achievement of this goal were SEC-AEC-HPLC for two-dimensional separation of cytosolic biomolecules, HR ICP-MS for metal measurements, and mass spectrometry (MALDI-TOF-MS and LC-MS/MS) for biomolecule mass determination and identification. The analyzed biomolecules included: Fe-binding biomolecules, which were identified as hemoglobin subunit β in the liver (molecular masses of ∼15 kDa), and hemoglobin subunits α and β in the gills (molecular masses of ∼11 kDa, ∼13 kDa and ∼15 kDa); heat-stable Cd-binding biomolecules, which were identified as MT isoforms MT-I and MT-II (molecular mass of ∼6.0 kDa in both liver and gills, and an additional 4.9 kDa isoform in the gills); and heat-stable Mo-binding biomolecules of molecular masses equal to 3.3 kDa (in the gills) and 8.5 kDa (in the liver). An important finding of this study was the obvious presence of different isoforms of the same biomolecules in the liver and gills. This was, among others, manifested through the absence of Zn binding to MTs only in the gills, indicating that the same type of biomolecule can be responsible for different functions in different organs. Thus, for better understanding of metal behaviour in aquatic organisms, it is crucial to identify cellular metal-binding biomolecules and their functions.
Result of the first ozone monitoring in ambient air Nature Park of Kopački Rit (Eastern Croatia) are reported for the growth season in 2008. The measured hourly concentrations of ozone in the air do not exceed the limit value of 110 μg m–3 statutory regulation by Croatian legalization for the protection of human health. There were only 13 days exceeding of the target value of 120 μg m–3 (8-h averages) as established in the European Union guidelines on ozone pollution in ambient air. In contrast to the measured AOT40 whose value does not exceed the critical level of 18 000 (μg m–3) ·h for vegetation injury, an estimated AOT40 value was somewhat higher. The relationships between O3 and meteorological variables were investigated by a principal component analysis (PCA). Fourier analysis methods applied to ozone concentrations data showed that the most important variations in the O3 data are represented by usual daily cycles. (doi: 10.5562/cca2147
22 January 2013 in Environmental Science and Pollution Research