Search results for "salmon"
showing 10 items of 354 documents
Biphenyl and fluorinated derivatives: liver enzyme-mediated mutagenicity detected in Salmonella typhimurium and Chinese hamster V79 cells.
1992
Abstract Hepatocarcinogenic polychlorinated and polybrominated biphenyls usually show negative results in in vitro mutagenicity assays. Problems in their testing result from their low water solubility and their slow rate of metabolism. We therefore investigated better soluble model compounds, namely biphenyl and its 3 possible monofiuorinated derivatives. In the direct test, these compounds proved tobe nonmutagenic in Salmonella typhimurium TA98 and TA100 (reversion to histidine prototrophy) and in Chinese hamster V79 cells (acquisition of resistance to 6-thioguanine). However, when the exposure was carried out in the presence of NADPH-fortified postmitochondrial fraction of liver homogenat…
Mutagenicity spectra in Salmonella typhimurium strains of glutathione, L-cysteine and active oxygen species
1989
Glutathione and L-cysteine, in the presence of rat kidney post-mitochondrial supernatant (S9) fraction, and various forms of active oxygen were investigated for mutagenicity in seven his- strains of Salmonella typhimurium. Glutathione and L-cysteine showed qualitatively and quantitatively virtually identical mutagenic activities. The number of mutants induced in strain TA97 was 3-4 times higher than in TA100, the strain in which the mutagenicity was originally detected. Mutagenic effects were also observed in strains TA92, TA102 and TA104, but not in TA1535 and TA1537. Hydrogen peroxide, superoxide and glucose/glucose oxidase in the presence and absence of kidney S9 fraction showed pronounc…
Inactivation of electrophilic metabolites by glutathione S-transferases and limitation of the system due to subcellular localization
1977
Benzo(a)pyrene was activated to metabolites mutagenic for Salmonella typhimurium TA 98 by liver microsomes from control and phenobarbital treated mice. Under these conditions benzo(a)pyrene 4,5-oxide accounts for most of the mutagenicity. We have therefore investigated (1) the conjugation of benzo(a)pyrene 4,5-oxide with glutathione and (2) the effect of glutathione on the mutagenicity of benzo(a)pyrene.
Metabolic epoxidation of trans-4-acetylaminostilbene: A protective mechanism against its activation to a mutagen
1976
Abstract Trans -4-acetylaminostilbene is activated by liver preparations to mutagens for Salmonella typhimurium . Since this compound is metabolized to the trans -α,β-epoxide and since many epoxides are ultimate mutagens, this epoxide was tested for direct mutagenicity. It was, however, found to be non-mutagenic, and, in contrast to the parent compound, the epoxide was no longer activated by liver preparations to mutagens. The same was found for the β-ketone and for the threo -α,β-dihydrodiol, which are formed metabolically from trans -4-acetylaminostilbene and from its α,β-epoxide. 4-Acetylaminobibenzyl showed a very weak mutagenic activity in the presence of the liver preparation. Thus, i…
The effect of dietary imbalances on the activation of benzo[a]pyrene by the metabolizing enzymes from rat liver.
1987
Abstract Male Sprague-Dawley rats (70–80 g) were fed ad libitum a standard control diet (22% casein, 5% lard), or a high lipid diet (30% lard) or a low protein diet (6% casein) or a standard diet containing 50 ppm phenoclor DP6. After 6 weeks on these diets, the cytochrome P-450 microsomal content, the benzo[ a ]pyrene monooxygenase (BaP-MO) and the epoxide hydrolase (EH) were assayed. The formation of mutagenic B(a)P metabolites which covalently bind with DNA was compared. The activity of BaP-MO and of EH were increased by the high lipid diet (+27% and 106% respectively) and by the phenoclor DP6 treatment (+63% and 400% respectively), compared to the standard diet. In animals fed a low pro…
EFFECT OF TRIAENOPHORUS CRASSUS (CESTODA) INFECTION ON BEHAVIOR AND SUSCEPTIBILITY TO PREDATION OF THE FIRST INTERMEDIATE HOST CYCLOPS STRENUUS (COPE…
2000
Some parasites have been shown to manipulate host behavior so that parasite transmission to the next host is enhanced. Infection with Triaenophorus crassus Forel (Cestoda) caused alterations in the activity and microhabitat selection of the first intermediate host Cyclops strenuus Fischer (Copepoda) in the laboratory. Infected copepods made more starts to swim but spent less time swimming than uninfected copepods. These changes were independent of the intensity of infection. In a water column illuminated from above, infected copepods approached the surface, whereas uninfected ones remained close to the bottom. In the dark both infected and uninfected copepods stayed near the bottom. Finally…
Association Mapping Based on a Common-Garden Migration Experiment Reveals Candidate Genes for Migration Tendency in Brown Trout
2019
A better understanding of the environmental and genetic contribution to migratory behavior and the evolution of traits linked to migration is crucial for fish conservation and fisheries management. Up to date, a few genes with unequivocal influence on the adoption of alternative migration strategies have been identified in salmonids. Here, we used a common garden set-up to measure individual migration distances of generally highly polymorphic brown trout Salmo trutta from two populations. Fish from the assumedly resident population showed clearly shorter migration distances than the fish from the assumed migratory population at the ages of 2 and 3 years. By using two alternative analytical …
Novel silver-based nanoclay as an antimicrobial in polylactic acid food packaging coatings.
2010
This paper presents a comprehensive performance study of polylactic acid (PLA) biocomposites, obtained by solvent casting, containing a novel silver-based antimicrobial layered silicate additive for use in active food packaging applications. The silver-based nanoclay showed strong antimicrobial activity against Gram-negative Salmonella spp. Despite the fact that no exfoliation of the silver-based nanoclay in PLA was observed, as suggested by transmission electron microscopy (TEM) and wide angle X-ray scattering (WAXS) experiments, the additive dispersed nicely throughout the PLA matrix to a nanoscale, yielding nanobiocomposites. The films were highly transparent with enhanced water barrier …
The effect of intermittent feeding on feed intake and compensatory growth of whitefish Coregonus lavaretus L.
2009
Abstract Groups of juvenile whitefish, Coregonus lavaretus , were exposed for 6 weeks to three different feeding regimes: control (fed every day); 2 + 5 (fed during weekdays); and 2 + 2 (fed 2 days, starved 2 days). The fish in the 2 + 2 group ate and grew less than the controls but the 2 + 5 group was intermediate and did not differ statistically significantly from either of the other two groups. The fish in both treatment groups exhibited clear compensation for the reduced number of feeding days by increasing intake and consequently weight gain during the days when they were fed, and the compensation increased towards the end of the experiment. Feeding treatments induced clear changes in …
Impact of Gluten-Friendly Bread on the Metabolism and Function of In Vitro Gut Microbiota in Healthy Human and Coeliac Subjects
2016
The main aim of this paper was to assess the in vitro response of healthy and coeliac human faecal microbiota to gluten-friendly bread (GFB). Thus, GFB and control bread (CB) were fermented with faecal microbiota in pH-controlled batch cultures. The effects on the major groups of microbiota were monitored over 48 h incubations by fluorescence in situ hybridisation. Short-chain fatty acids (SCFAs) were measured by high-performance liquid chromatography (HPLC). Furthermore, the death kinetics of Lactobacillus acidophilus, Bifidobacterium animalis subsp. lactis, Staphylococcus aureus, and Salmonella Typhimurium in a saline solution supplemented with GFB or CB were also assessed. The experiment…