Doxorubicin-induced F-actin reorganization in cofilin-1 (nonmuscle) down-regulated CHO AA8 cells.

The actin cytoskeleton plays an important role in many cellular processes, including cell mortality, mitosis, cytokinesis, intracellular transport, endocytosis and secretion but also is involved in gene transcription. The dynamics of the actin cytoskeleton is controlled by different classes of actin-binding proteins (ABPs) which regulate the polymerization of actin filaments. In this report we used siRNA against cofilin-1 (nonmuscle) to demonstrate the effect of cofilin on the nuclear and cytoplasmic actin pools in CHO AA8 cells after exposition to various concentrations of doxorubicin. The immunofluorescence studies showed doxorubicin dose dependent tendency to formation the multinucleated giant cells, but also the increase of fluorescence intensity of cofilin in nuclei of untransfected cells. Induction of cell death with doxorubicin treatment in untransfected cells revealed both mitotic catastrophe (in both lower and higher doxorubicin doses) and apoptosis (mostly in higher doxorubicin doses), whereas among cofilin-1 down-regulated cells we observed only mitotic catastrophe. The results suggest that cofilin has apoptosis-inducing ability and that mitotic catastrophe is independent from F-actin content in cell nucleus. In this point of view we conclude that different mechanisms of chromatin reorganization are involved in these two processes. Moreover, we suppose that apoptosis and mitotic catastrophe are independent from each other

Effect of Parameters on Oxychlorination of Tert-Butyl Ethers

The effect of concentration, molar ratios of reagents, pH, and temperature on formation of chloro-organic products in reaction of tert-butyl ethers with chloride ions and hydrogen peroxide has been determined. A significant effect of Cl− ions and H2O2 molar ratios on the rate of chloro-organic product formation has been observed. Studies on oxychlorination of tert-butylethyl ether (ETBE) at pH 7, 3.5, and 2.5 have been carried out. It was found that introduction of hydronium ions into the reaction system considerably hastened the process of chloro-organic product formation. Hydronium ions contribute to the formation of the reactive tert-butyl carbocation, which undergoes secondary reactions in the presence of reactive forms of chlorine and oxygen. Moreover, the effect of temperature on ETBE (tert-butylethyl ether) and MTBE (tert-butylmethyl ether) conversions was verified. The reactions of MTBE and ETBE oxychlorination were carried out at temperatures of 5°C, 20°C, and 35°C

Comparison of Methods For Ethylhexyl 4-Methoxycinnamate Acid Ester Oxidation In Water Medium

The aim of the studies was to compare an impact of oxidizing agents on degradation of ethylhexyl 4-methoxycinnamate acid (EHMC). The oxidation reaction was carried out in the presence of sodium hypochlorite, hydrogen peroxide and ozone with/without UV radiation. EHMC degradation and the analysis of products were performed using gas chromatograph coupled with a mass spectrometry detector. The most effective method of EHMC degradation turned out to be ozonation with participation of UV radiation. In this system, degradation proceeded most quickly and generated a small amount of by-products (2-propyl-1-pentanol; 4-metoxybenzaldehyde and Z-EHMC). Under the influence of sodium hypochlorite, numerous chloroorganic products were formed, which can cause secondary contamination of water. Application of appropriate oxidation processes can contribute to degradation of micropollutants and thus to improvement of water quality

Effect of UV radiation on the fastness of selected UV filters

Przeprowadzono badania trwałości wybranych filtrów UV: 1- (4’ - t -bu t y lof e n y lo) -3- (4’ ’ -me tok s y f e n y lo - )propa no -1,3-dion (MBBM), 1,3-bis-(4’-metoksyfenylo)propano-1,3-dion (MMBM) i 1-(4’-t-metoksyfenylo)-3-fenylopropano-1,3-dion (MBM). Sprawdzono wpływ promieniowania UV oraz obecności czynnika utleniają- cego (nadtlenku wodoru) i źródła jonów chlorkowych (chlorku sodu) na trwałość wybranych filtrów. Wykazano, że istotne znaczenie na trwałość badanych związków mają układy H2 O2 :UV i H2 O2 :NaCl:UV.Studies on the fastness of selec ted UV filters: 1-(4’-t-butylphenyl)-3-(4’’-methoxyphenyl)propane-1,3-dione (MBBM), 1,3-bis-(4’- methoxyphenyl)propane-1,3-dione (MMBM) and 1-(4’-t-methoxyphenyl)-3-phenylpropane-1,3-dione (MBM) were carried out. Effect of UV radiation, presence of an oxidizing agent (hydrogen peroxide) and source of chloride ions (sodium chloride) on the fastness of selected filters was investigated. It was found that the systems H2 O2 :UV and H2 O2 :NaCl:UV were of the essential importance on the fastness of compounds studied

Removal of 2-phenylbenzimidazole-5-sulfonic acid using heterogeneous photocatalysis

UV filters are classified as environmental pollutants (emerging pollutants). One of the most frequently detected UV filters in real samples is 2-phenylbenzimidazole-5-sulfonic acid (PBSA). It has been shown that conventional technologies applied in sewage treatment plants are not adapted for complete removal of sunscreen agents. Therefore, there is a trend to undertake activities leading to improvement of water quality by enhancing treatment methods. This is important due to the fact that in an aqueous environment, in the presence of UV radiation or sunlight irradation, PBSA generates reactive oxygen species that can damage the DNA of living organisms. The aim of study was to investigate an effect of pH and TiO2 on PBSA stability in the presence of UV radiation. It was found that the rate of PBSA degradation depends on the catalyst dose and pH of solution. The photocatalysis reaction was carried out in a Heraeus laboratory exposure set equipped with a 150 W medium pressure mercury lamp. The course of PBSA degradation process as a function of time was monitored using UV/VIS spectrophotometer and liquid chromatograph equipped with UV-Vis detector

Determination of selected UV filters in water samples

W artykule przedstawiono metody oznaczania wybranych filtrów UV w próbkach wody i ścieków. Opisano procedurę wzbogacania i izolacji dwóch filtrów UV z próbek wody i ścieków. Do analizy wykorzystano chromatograf gazowy sprzężony z detektorami płomieniowo-jonizacyjnym i spektrometrii mas (GC-FID-MS) oraz chromatograf cieczowy wyposażony w detektor z matrycą diod (HPLC-UV-DAD). Dla obu metod wykonano walidację. Etyloheksylo- metoksycynamonian (EHMC) i 1-(4'-t-butylofenylo)-3-(4''-metoksyfenylo-)propano-1,3-dion (MBBM) oznaczono w próbkach wody i ścieków kąpielowych. Oznaczono granicę wykrywalności i oznaczalności oraz wartość odzysku badanych związków. Uzyskano zadowalającą precyzję (RSD 5 -15 %). Przeprowadzono wstępne badania trwałości EHMC pod wpływem działania promieniowania UV. Wykazano, że produktem degradacji EHMC jest pochodna kwasu cynamonowego.Methods for the determination of selected UV filters in water and wastewater samples have been presented. Procedure for enrichment and isolation of two UV filters from water and wastewater samples was described. Gas chromatograph coupled with flame ionization detector and mass spectrometry (GC-FID-MS) as well as liquid chromatograph equipped with UV and Diode Array (HPLC-UVDAD) detectors were used for the analysis. For both the methods, validation was performed. 2-Ethylhexyl 3- (4-methoxyphenyl)-2- propenoate (EHMC) and 1-(4'-t-butylphenyl)-3-(4''-methoxyphenyl-) propane-1,3-dione (MBBM) were determined in samples of water and bathing wastewater. Limit of detection, limit of quantification and recovery of the tested compounds were determined. The precision was satisfactory (RSD 5-15 %). Preliminary studies on stability of EHMC under influence of UV radiation were carried out. It was found that cinnamic acid derivative was the product of EHMC degradation