Search results for "Cyclic compound"
showing 10 items of 819 documents
Molecular docking and oxidation kinetics of 3-phenyl coumarin derivatives by human CYP2A13
2021
CYP2A13 enzyme is expressed in human extrahepatic tissues, while CYP2A6 is a hepatic enzyme. Reactions catalysed by CYP2A13 activate tobacco-specific nitrosamines and some other toxic xenobiotics in lungs.To compare oxidation characteristics and substrate-enzyme active site interactions in CYP2A13 vs CYP2A6, we evaluated CYP2A13 mediated oxidation characteristics of 23 coumarin derivatives and modelled their interactions at the enzyme active site.CYP2A13 did not oxidise six coumarin derivatives to corresponding fluorescent 7-hydroxycoumarins. The Km-values of the other coumarins varied 0.85���97 ��M, Vmax-values of the oxidation reaction varied 0.25���60 min���1, and intrinsic clearance var…
Substrate Selectivity of Coumarin Derivatives by Human CYP1 Enzymes: In Vitro Enzyme Kinetics and In Silico Modeling
2021
Of the three enzymes in the human cytochrome P450 family 1, CYP1A2 is an important enzyme mediating metabolism of xenobiotics including drugs in the liver, while CYP1A1 and CYP1B1 are expressed in extrahepatic tissues. Currently used CYP substrates, such as 7-ethoxycoumarin and 7-ethoxyresorufin, are oxidized by all individual CYP1 forms. The main aim of this study was to find profluorescent coumarin substrates that are more selective for the individual CYP1 forms. Eleven 3-phenylcoumarin derivatives were synthetized, their enzyme kinetic parameters were determined, and their interactions in the active sites of CYP1 enzymes were analyzed by docking and molecular dynamic simulations. All cou…
Small molecule modulators of amine oxidation, nuclear receptor signaling and glucuronidation : 3-phenylcoumarin as a scaffold of interest
2018
The costs of the drug development process are moderated as computer-aided drug design methods are able to expedite the steps required for lead identification. In fact, computational tools are nowadays virtually indispensable from target identification and validation to preclinical tests due to exponential growth of available information regarding both potential targets and small molecules. One such small molecule with growing number of variations is coumarin. Coumarin scaffold and its various derivatives continue to interest researchers for their vast application potential. Since naturally occurring coumarins are known for example for their antioxidant and anti-inflammatory properties, thos…
Heat treatment of vegetable oils. II. GC-MS and GC-FTIR spectra of some isolated cyclic fatty acid monomers
1987
Gas liquid chromatography coupled with mass spectrometry (GC-MS) showed that the cyclic fatty acid monomers (CFAM) isolated from a heated linseed oil have two ethylenic bonds, while the CFAM isolated from heated sunflower oils were saturated and monoethylenic isomers. GC-MS studies also showed the presence of cyclohexenic derivatives in the case of linseed oil.
Fruits and vegetables protect against the genotoxicity of heterocyclic aromatic amines activated by human xenobiotic-metabolizing enzymes expressed i…
2010
Heterocyclic aromatic amines (HAAs) can be formed during the cooking of meat and fish at elevated temperatures and are associated with an increased risk for cancer. On the other hand, epidemiological findings suggest that foods rich in fruits and vegetables can protect against cancer. In the present study three teas, two wines, and the juices of 15 fruits and 11 vegetables were investigated for their protective effect against the genotoxic effects of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). To closely mimic the enzymatic activation of these HAAs in humans, genetically engineered V79 Chinese hamster fibroblasts were employed tha…
Visually induced motion sickness and presence in videogames: The role of sound
2012
Visually induced motion sickness (VIMS) is a well-known phenomenon in virtual environments, simulators, and videogames. We conducted an experiment to analyze the role of sound on the severity of VIMS and the feeling of presence in videogames. Thirty-two subjects first watched a pre-recorded sequence of the game “Mirrors Edge” and then played the game actively. Game-play sound was activated for half of the participants. VIMS was measured via the Simulator Sickness Questionnaire and the Fast Motion Sickness Scale, presence was captured using the Presence Questionnaire. Results showed severe VIMS in all participants during the passive video session, whereas active-play revealed only moderate …
Elevated polycyclic aromatic hydrocarbons in a river floodplain soil due to coal mining activities
2007
Elevated PAH concentrations were found in soil samples collected along the Mosel River. These contaminations were associated with the occurrence of coal particles found in the soil. The majority of the PAH contamination in the soils was linked to coal mining activities in the Saar region. Density and grain size separation showed a similar PAH distribution pattern in all of the fractions, indicating a uniform origin of PAHs. Together with coal petrography a good correlation between TOC and PAHs concentration confirmed the impact of former coal mining activity on the PAHs distribution in study area.
Organocatalytic approach to benzofused nitrogen-containing heterocycles: enantioselective total synthesis of (+)-angustureine.
2008
Additional file 8: of A two-gene epigenetic signature for the prediction of response to neoadjuvant chemotherapy in triple-negative breast cancer pat…
2019
Sequence of primers used by pyrosequencing in the validation assay of candidate genes obtained from 450k array (PPT 143 kb)
Additional file 7: of A two-gene epigenetic signature for the prediction of response to neoadjuvant chemotherapy in triple-negative breast cancer pat…
2019
Clinical inclusion and exclusion criteria followed to select TNBC patients for the methylation study (PPT 89 kb)