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Melanoma is the most dangerous type of cancer, with a high rate of metastasis. The conventional method of treating skin melanoma is photodynamic therapy, yet this type of phototherapy has several side effects. In addition, the photosensitizers used are relatively expensive and toxic. Thus, developing methods of treating melanoma cancer using laser only is a promising area of research. Here we present in vitro effects in melanoma cell culture after 1265 nm laser irradiation exposure.

Near-infrared laser therapy has a significantly greater ability to penetrate living tissues compared to visible range optical radiation and often has the opposite effect on normal and malignant cells, thus being a promising tool for superficial neoplasm therapy. However, the mechanisms underlying the interaction between laser and biological structures can be of a different nature due to the chosen wavelength, power, and other radiation parameters. The aim of the paper is to study the efficacy of laser radiation with a wavelength of 1265 nm (9.45–18.9 J/cm2) on the generation of reactive oxygen species (ROS), the enzyme level of the antioxidant defence (AOD) and lipid peroxidation (LPO) in normal and cancer cells of Chinese hamster ovary epithelial cell line CHO-K1 and human melanoma A875. Materials and Methods. The experiment was carried out on cell lines CHO-K1 and A875, which were submitted to laser irradiation (wavelength 1265 nm, power 4.2–100 mW) for 30–60 min. Fluorescent staining with DCFH-DA was used to study intracellular ROS concentration; ImageJ software was used for image processing. The level of LPO products and the activity of AOD enzymes were determined by biochemical methods. Statistical processing of the results was carried out using the Mann–Whitney U-test (p

We studied the effect of inhibition of mitochondrial voltage-dependent anion channels with DIDS on radiosensitivity and mitochondrial status of K562 leukemic cells. The number of apoptotic and necrotic cells, mitochondrial transmembrane potential, and mitochondrial mass were evaluated after irradiation of cells in doses of 4 and 12 Gy in the presence and absence of the inhibitor. Inhibition of mitochondrial voltage-dependent anion channels increased radiosensitivity of K562 cells by 50-70% and decreased both mitochondrial transmembrane potential and mitochondrial mass. Inhibitors of voltage-dependent anion channels are promising agents capable of improving the effectiveness of cancer radiotherapy.

Phosphogypsum (CaSO4·2H2O) is heavy tonnage waste generated by binding calcium in the process of sulfuric acid decomposition of phosphate raw materials when obtaining wet-process phosphoric acid in the production of phosphate fertilizers. In appearance, it is solid fine-crystalline substance of white or gray color with inclusions of large aggregates. The paper presents the results of laboratory studies of more than 390 samples of phosphogypsum neutralized with construction lime. The deformation and strength properties as well as the water permeability were determined on specially prepared samples with the relative compaction of 0.95, 0.90 and 0.80 by methods used in engineering and geological surveys. While the angle of internal friction, the cohesion and the coefficient of permeability of the phosphogypsum have the values typical for fine or silty sands, the compressibility characteristics are significantly worse due to the solubility of the particles. Phosphogypsum is characterized by subsidence and suffusion settling, which are proper for carbonate rocks (dolomite, limestone). The use of the phosphogypsum as ground is possible for subbase of roads with low traffic intensity with a gravel pavement, for dams at industrial solid waste storage facilities, as well as for engineering reclamation of those storage facilities, but only if implementing water protection measures.

Radiation-induced accumulation of active oxygen species and the role of the mitochondria in this process were studied on cultured K562 leukemia cells. Intracellular concentrations of active oxygen species in the presence of rotenone and without it and the mitochondrial potential were analyzed 15, 30 min, 1, 4, 8, 12, 24, and 48 h after X-ray exposure in doses of 4 and 12 Gy. Radiation-induced generation of active oxygen species had two time peaks: 30 min and 24 h after the exposure. Addition of rotenone reduced the levels of active oxygen species 24 and 48 h after the exposure. Increase of active oxygen species concentrations was paralleled by an increase of the mitochondrial potential. The mitochondria were responsible for the increase in the concentrations of active oxygen species 12-48 h after irradiation.

The aim of this study was to examine the effect of doxorubicin and menadione on cell proliferation, cell cycle, glutathione concentration, the expression of ribonucleotide reductase, and the Yap1 dependent redox-sensitive pathway in Saccharomyces cerevisiae as a eukaryote cell model. Our data showed that menadione induced cell-cycle arrest in the G1 phase, decreased intracellular GSH and GSSG concentrations, dose-dependently increased expression of ribonucleotide reductase and the activity of Yap1 pathway. Doxorubicin induced the cell-cycle arrest in G1 and S phases, increased the GSH and GSSG concentration and the expression of ribonucleotide reductase, and modulated the Yap-dependent pathway activity.