Search results for "DASE"
showing 10 items of 1891 documents
Study of enzymatic activity in human neuroblastoma cells SH-SY5Y exposed to zearalenone's derivates and beauvericin.
2021
Abstract Beauvericin (BEA), α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL), are produced by several Fusarium species that contaminate cereal grains. These mycotoxins can cause cytotoxicity and neurotoxicity in various cell lines and they are also capable of produce oxidative stress at molecular level. However, mammalian cells are equipped with a protective endogenous antioxidant system formed by no-enzymatic antioxidant and enzymatic protective systems such as glutathione peroxidase (GPx), glutathione S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD). The aim of this study was evaluating the effects of α-ZEL, β-ZEL and BEA, on enzymatic GPx, GST, CAT and SOD activity in huma…
Intestinal anti-inflammatory activity of ellagic acid in the acute and chronic dextrane sulfate sodium models of mice colitis.
2013
Abstract Ethnopharmacological relevance Pomegranate (Punica granatum L.; Lythraceae) has traditionally been used for the treatment of various inflammatory diseases, including ulcerative colitis (UC). Because its fruits and extracts are rich in ellagitannins, which release ellagic acid when hydrolyzed, consumption of pomegranate products is currently being widely promoted for their potential health effects, including the prevention of inflammatory diseases and cancer. To evaluate the anti-inflammatory effects of ellagic acid on dextran sulfate sodium (DSS)-induced acute and chronic experimental colitis in two different strains of mice and to elucidate its possible mechanisms of action. Mater…
Performance of industrial strains of Saccharomyces cerevisae during wine fermentation is affected by manipulation strategies based on sporulation.
2002
Genetic manipulation of industrial wine yeast strains has become an essential tool for both the study of the molecular mechanisms underlaying their physiology and the improvement of their fermentative properties. The construction of null mutants for any gene in these usually diploid strains, by using a procedure based on sporulation of a heterozygote lacking one copy of the gene of interest, has been tested as an alternative to the tedious work of sequential disruption of the complete set of copies. Our results indicate that most of the homozygotes resulting from sporulation of wine yeast strains are defective in glucose consumption under microvinification conditions in synthetic must and p…
Effects of yeast proteolytic activity on Oenococcus oeni and malolactic fermentation
2006
International audience; Alcoholic fermentation of synthetic must was performed using either Saccharomyces cerevisiae or a mutant Delta pep4, which is deleted for the proteinase A gene. Fermentation with the mutant Delta pep4 resulted in 61% lower levels of free amino acids, and in 62% lower peptide concentrations at the end of alcoholic fermentation than in the control. Qualitative differences in amino acid composition were observed. Changes observed in amino acids in peptides were mainly quantitative. After alcoholic fermentation each medium was inoculated with Oenococcus oeni. Malolactic fermentation in the medium with the Delta pep4 strain took 10 days longer than the control. This diffe…
Trx2p-dependent Regulation of Saccharomyces cerevisiae Oxidative Stress Response by the Skn7p Transcription Factor under Respiring Conditions
2013
The whole genome analysis has demonstrated that wine yeasts undergo changes in promoter regions and variations in gene copy number, which make them different to lab strains and help them better adapt to stressful conditions during winemaking, where oxidative stress plays a critical role. Since cytoplasmic thioredoxin II, a small protein with thiol-disulphide oxidoreductase activity, has been seen to perform important functions under biomass propagation conditions of wine yeasts, we studied the involvement of Trx2p in the molecular regulation of the oxidative stress transcriptional response on these strains. In this study, we analyzed the expression levels of several oxidative stress-related…
A short-range gradient of histone H3 acetylation and Tup1p redistribution at the promoter of the Saccharomyces cerevisiae SUC2 gene.
2003
Chromatin immunoprecipitation assays are used to map H3 and H4 acetylation over the promoter nucleosomes and the coding region of the Saccharomyces cerevisiae SUC2 gene, under repressed and derepressed conditions, using wild type and mutant strains. In wild type cells, a high level of H3 acetylation at the distal end of the promoter drops sharply toward the proximal nucleosome that covers the TATA box, a gradient that become even steeper on derepression. In contrast, substantial H4 acetylation shows no such gradient and extends into the coding region. Overall levels of both H3 and H4 acetylation rise on derepression. Mutation of GCN5 or SNF2 lead to substantially reduced SUC2 expression; in…
A microplate version of the SOS/umu-test for rapid detection of genotoxins and genotoxic potentials of environmental samples
1991
Abstract The umu-microtest is a miniaturized automated short-term test version proposed for screening of umuC-dependent mutagenic potentials of chemicals relevant to environmental pollution, river water and industrial waste water. The test is based on the SOS/umu-test and has been modified in order to allow extensive testing of environmental samples. Genetically engineered Salmonella typhimurium (TA1535/pSK1002) are incubated on a microplate rotor in a sloping position for 2 h with the test samples, followed by addition of fresh culture medium to reach a 10-fold dilution of the incubation medium. 2 h later, the activity of the β-galactosidase, which reflects umuC induction, is determined co…
Evaluation of the SOS/umu-test post-treatment assay for the detection of genotoxic activities of pure compounds and complex environmental mixtures.
2000
This study presents an evaluation of the SOS/umu-test after introducing an additional dilution and incubation in the post-treatment assay. This treatment reduces the influence of coloured test compounds that otherwise affect the colorimetric determination of the beta-galactosidase activity and the bacterial growth measurement during the testing of complex environmental samples. The post-treatment assay significantly increased the beta-galactosidase activity and consequently the enzyme induction ratios at higher doses of model genotoxins 4-nitroquinoline-N-oxide, N-methyl-N'-nitro-N-nitrosoguanidine, 2-aminoanthracene, benzo(a)pyrene with low or no effect on the sensitivity of the test itsel…
Increase of sensitivity and validity of the SOS/umu-test after replacement of the beta-galactosidase reporter gene with luciferase.
1998
The SOS/umu-test with Salmonella typhimurium TA1535/pSK1002 as tester strain is a rapid and valuable bacterial assay for screening of umuC-dependent mutagenic potential of chemical compounds and chemicals relevant to environmental pollution. The initial assay was modified by replacing the beta-galactosidase reporter gene with luciferase. Thereby, the sensitivity of the umu-test was increased significantly and the susceptibility to intensively coloured solutions was reduced. The alternative enzyme assay in the modified umu-test (umu-Luc) represents an independent method which allows to confirm the colorimetric results obtained with the original SOS/umu-test system (umu-Gal) by measuring the …
La enfermedad como rasgo humano. Hacia una consideración de la enfermedad en cuanto fenómeno existencial
2018
Resumen En el presente trabajo se investigan los alcances y las consecuencias que se desprenden de utilizar a Heidegger en el campo de la filosofía de la medicina. Con este fin, la investigación se divide en los siguientes puntos: 1) se explicitará en qué puede consistir una “antropologización” del pensamiento heideggeriano; 2) se ofrecerá una descripción general respecto de las teorías de la salud y enfermedad más significativas y actuales en el campo de la teoría de la medicina; 3) nos detendremos en el análisis relacionado con el problema de la enfermedad desde una perspectiva heideggeriana, para finalmente, 4) ofrecer algunas reflexiones críticas en relación con el análisis …