Katarzyna Walczak

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BACKGROUND Kynurenic acid (KYNA), a tryptophan metabolite, was found in human saliva, gastric juice, bile, pancreatic juice and mucus of rat small intestine. METHODS KYNA content in mucus aspirated from human caecum or colon ascendens and KYNA production in colon epithelial and cancer cells were determined using HPLC. Moreover, biological properties of(More)
BACKGROUND Kynurenic acid (KYNA), tryptophan metabolite synthesized in the kynurenine pathway, is an endogenous antagonist of α-7 nicotinic receptor and all ionotropic glutamate receptors: N-methyl-D-aspartate (NMDA) receptor, α-amino-3-hydroxy-5-methyl-4-isoxasole propionate (AMPA) receptor and kainate receptor. The antiproliferative activity of KYNA(More)
This paper describes the study conducted to evaluate the antiproliferative activity of ether and ethanol extracts isolated from Piptoporus betulinus against cancer-derived cells. The fungal material used for extract preparation and further experiments was obtained from in vitro grown strains of P. betulinus. To the best of the authors’ knowledge, this is(More)
Kynurenic acid (KYNA), a tryptophan metabolite, inhibits proliferation of several cancer cell lines including colon cancer, renal cancer and glioblastoma cells. Previous studies reported that inhibitory properties of KYNA may be related to interactions of KYNA with cell cycle regulators and signaling proteins. However, the exact molecular interaction of(More)
Kidneys possess a complex enzyme system which plays a major role in tryptophan metabolism. Taking into account a considerably high concentration of one of the tryptophan metabolites, kynurenic acid (KYNA) in this organ and previously reported antiproliferative activity against colon cancer cells in vitro, we measured its content in human normal and tumour(More)
BACKGROUND AND OBJECTIVE Alpha-ketoglutarate (AKG), a key intermediate in Krebs cycle, is an important biological compound involved in the formation of amino acids, nitrogen transport, and oxidation reactions. AKG is already commercially available as a dietary supplement and its supplementation with glutamine, arginine, or ornithine alpha-ketoglutarate has(More)
BACKGROUND Kynurenic acid (KYNA), a tryptophan metabolite, was found in the mucus of rat small intestine. However, its role in the gastrointestinal tract is still not fully elucidated. METHODS To verify whether KYNA affects cell cycle regulators, the protein expression of cyclin-dependent kinase inhibitor p21 Waf1/Cip1 was investigated in colon(More)
A new one-step synthesis of novel biologically active 2-substituted 2,4-dihydroxyphenyl-4 $$H$$ H -thieno[3,2- $$d$$ d ][1,3]thiazin-4-ones and 4 $$H$$ H -thieno[2,3- $$d$$ d ][1,3]thiazin-4-ones has been elaborated and described. The compounds were prepared by the reaction of aryl-modified sulfinylbis [(2,4-dihydroxyphenyl)methanethione]s and the(More)
2-(2,4-Dihydroxyphenyl)thieno-1,3-thiazin-4-ones are a group of new compounds with potential anticancer activity. This type of derivatives was poorly investigated in the area of synthesis and biological activities. In the present study the antiproliferative action of the most active derivative BChTT was described. The aim of biological evaluation was to(More)
BACKGROUND There are about 200 underground tourist routes in Poland. There are caves, mines or underground structures. This paper presents the results of the research intended to identify the extent of the occurrence of radon concentrations in underground areas of tourist routes. MATERIAL AND METHODS We conducted the measurement of periodic concentrations(More)