COMBINATION OF ATOMIC FORCE MICROSCOPY AND COMET ASSAY FOR ANALYSIS OF DNA DAMAGE INDUCED BY PDT

The aim of the present study was to evaluate the efficiency of photosensitisation induced by two photosensitizers, TMPyP and ClAlPcS2, tested in vitro on the tumor cell line MCF7. The oxidative damage of DNA in MCF-7 cells was analyzed by comet assay (CA) combined with Atomic Force Microscopy (AFM). The ability of detection of apoptotic response detected by Atomic Force Microscopy at the individual molecule level of DNA was successfully demonstrated; when DNA get damaged, cleavage to fragments caused by photodynamic treatment was directly visualized by AFM imaging of individual molecules. Its accuracy and reliability was validated through the comparison with traditional single cell agarose electrophoresis

Wastewater Treatment by Novel Polyamide/Polyethylenimine Nanofibers with Immobilized Laccase

Endocrine-disrupting chemicals are highly resistant organic compounds, commonly occurring in the aquatic environment, that can interfere with the endocrine system of animals and humans, causing serious chronic diseases. In recent decades, enzymes from oxidoreductases have been studied for their potential to degrade these compounds effectively. In order to use such enzymes repeatedly, it is necessary to ensure their insolubility in water, a method termed enzyme immobilization. We developed novel polyamide/polyethylenimine (PA/PEI) nanofibers as a promising support material for the immobilization of various biomolecules. Our nanofibers are highly suitable due to a unique combination of mechanical endurance provided by polyamide 6 and their affinity toward biomolecules, ensured by numerous PEI amino groups. Enzyme laccase was successfully immobilized onto PA/PEI nanofibers using a simple and fast method, providing exceptional activity and stability of the attached enzyme. We then tested the degradation ability of the PA/PEI-laccase samples on a highly concentrated mixture of endocrine-disrupting chemicals in real wastewater with adjusted pH. The results indicate that the samples were a suitable material for wastewater treatment by degrading a highly concentrated mixture of bisphenol A, 17α-ethinylestradiol, triclosan, and diclofenac, in real wastewater effluent

XANTHENE DYES-MEDIATED IN VITRO PHOTODYNAMIC TREATMENT OF CANCER AND NON-CANCER CELL LINES

Rose bengal and erythrosin B are xanthene dyes mainly known and used as antimicrobial agents, but due to their photodynamic activity they are also potential photosensitizers for cancer photodynamic therapy. The aim of this work is to study a photodynamic efficacy of rose bengal and erythrosin B against human skin melanoma and mouse fibroblast cell lines, compare them with each other and find out their photodynamic properties induced by light emitting diodes with total light dose of 5 J/cm2. To fully identify and understand photodynamic properties of both potentially effective photosensitizers, a set of complex in vitro tests such as cell cytotoxic assay, measurement of reactive oxygen species production, mitochondrial membrane potential change assay, mode of cell death determination or comet assay were made. Although both photosensitizers proved to have similar properties such as increasing production of reactive oxygen species with the higher concentration, predominance of necrotic mode of death or genotoxicity, the more effective photosensitizer was rose bengal because its EC50 was over 20 times lower for both cell lines than in case of erythrosin B. &nbsp

IMUNOFLUORESCENČNÍ ANALÝZA PROAPOPTICKÝCH SIGNÁLNÍCH MOLEKUL V BUŇKÁCH LIDSKÉHO MELANOMU PO FOTODYNAMICKÉ TERAPII

IMMUNOFLUORESCENCE ANALYSIS OF PROAPOPTOTIC SIGNALING MOLECULES IN HUMAN MELANOMA CELLS AFTER PHOTODYNAMIC TREATMENT. Photodynamic therapy (PDT) is connected with oxidative damage of biomolecules causing significant impairment of essential cellular functions that lead to cell death. It is the reason, why photodynamic therapy has also found its application in treatment of different oncological, cardiovascular, skin and eye diseases. The cell death after PDT is mediated by an apoptotic and/or necrotic process including activation of various biomolecules. In the presented study we have used immunofluorescence method to detect caspase 3 and 9, poly ADP-ribose polymerase (PARP) in their active forms, and release of the cytochrome c as the proapoptotic protein after photodynamic treatment of human melanoma cells

VLIV ULTRAZVUKU NA ÚČINNOST FOTODYNAMICKÉ TERAPIE – IN VITRO STUDIE

Photodynamic therapy (PDT) belongs in perspective modalities of cancer treatment. It is based on the tumour-selective accumulation of a photosensitizer followed by irradiation with light of a specific wavelength. PDT is widely developed nowadays due to its high specificity and selectivity along with absence of the unadvisable side-effects. Sonodynamic therapy (SDT) exploits ultrasound to induce cytotoxic effect of sensitizer. In our study we tested the possibility of combination of this therapies and icrease of efficiency. Our results suggest that irradiation in combination with application of therapeutic ultrasound increases production of reactive oxygen species and reduces viability of tumour MCF7 cells, compared to irradiation of ZnTPPS4 only, especially in the case of higher therapeutic doses. In the future, the combination of PDT and SDT can bring a new treatment modality for malignant and also nonmalignant diseases

Vliv dluhu na hospodaření obcí

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Ekonomická fakulta. Katedra (153) veřejné ekonomik