Confocal micrographs: automated segmentation and quantitative shape analysis of neuronal cells treated with ostreolysin A/pleurotolysin B pore-forming complex.

Detailed shape analysis of cells is important to better understand the physiological mechanisms of toxins and determine their effects on cell morphology. This study aimed to develop a procedure for accurate morphological analysis of cell shape and use it as a tool to estimate toxin activity. With the aim of optimizing the method of cell morphology analysis, we determined the influence of ostreolysin A and pleurotolysin B complex (OlyA/PlyB) on the morphology of murine neuronal NG108-15 cells. A computational method was introduced and successfully applied to quantify morphological attributes of the NG108-15 cell line before and after 30 and 60 min exposure to OlyA/PlyB using confocal microscopy. The modified circularity measure [Formula: see text] for shape analysis was applied, which defines the degree to which the shape of the neuron differs from a perfect circle. It enables better detection of small changes in the shape of cells, making the outcome easily detectable numerically. Additionally, we analyzed the influence of OlyA/PlyB on the cell area, allowing us to detect the cells with blebs. This is important because the formation of plasma membrane protrusions such as blebs often reflects cell injury that leads to necrotic cell death. In summary, we offer a novel analytical method of neuronal cell shape analysis and its correlation with the toxic effects of the pore-forming OlyA/PlyB toxin in situ.

Synthesis of metastable hard-magnetic ε-Fe2O3 nanoparticles from silica-coated akaganeite nanorods.

We present a simple preparation route to obtain a nanoscale metastable hard-magnetic ε-Fe2O3 phase, using silica coated ß-FeOOH nanorods as a precursor and an annealing process. The synthesized ε-Fe2O3 nanoparticles exhibit large coercivity (HC ∼ 20 kOe at 300 K and HC ∼ 1.6 kOe at 400 K), confirming their high potential for practical applications.

Assessment of arsenic and mercury contamination in the Tisa River sediments and industrial canal sediments (Danube alluvial formation), Serbia.

The purpose of this study was to examine the levels of As and Hg and mobility of these contaminants in the sediments of the River Tisa and canal sediments (alluvial formation of the Danube River, Serbia), in order to determine the degree to which the ecosystem is harmed by these pollutants. The sequential extraction procedure (modified Tessier method) was used to extract the metals from the sediments. Arsenic is extracted in the second, third and fifth fraction, with dominant extraction in the second fraction. This distribution indicates that As is significantly present in the form of carbonates, whereas the part of As is present in the form of oxides. The most important extraction of Hg is in the fifth stage (extraction with 6M HCl), with over 80 % of extracted element in both types of sediment, indicating a strong association between Hg and Fe crystalline oxides as well as presence of Hg in the form of sulfides. Based on arsenic and mercury content in sediments and results of sequential extraction it can be concluded that on the studied localities there is no significant As and Hg contamination.