Search Results - "VAZ, Alfin D. N"

Deuterium isotope effects in drug pharmacokinetics II: Substrate-dependence of the reaction mechanism influences outcome for cytochrome P450 cleared drugs by Sun, Hao, Piotrowski, David W, Orr, Suvi T M, Warmus, Joseph S, Wolford, Angela C, Coffey, Steven B, Futatsugi, Kentaro, Zhang, Yinsheng, Vaz, Alfin D N

“…Two chemotypes were examined in vitro with CYPs 3A4 and 2C19 by molecular docking, metabolic profiles, and intrinsic clearance deuterium isotope effects with…”
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A tag-free collisionally induced fragmentation approach to detect drug-adducted proteins by mass spectrometry by Ballard, T. Eric, Dahal, Upendra P., Bessire, Andrew J., Schneider, Richard P., Geoghegan, Kieran F., Vaz, Alfin D. N.

“…Rationale The covalent modification of proteins by toxicants, new chemical entities or drug molecules, either by metabolic activation or the presence of…”
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Molecular etiology of atherogenesis--in vitro induction of lipidosis in macrophages with a new LDL model by Estronca, Luis M B B, Silva, Joao C P, Sampaio, Julio L, Shevchenko, Andrej, Verkade, Paul, Vaz, Alfin D N, Vaz, Winchil L C, Vieira, Otilia V

“…Atherosclerosis starts by lipid accumulation in the arterial intima and progresses into a chronic vascular inflammatory disease. A major atherogenic process is…”
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IN VITRO DRUG INTERACTIONS OF CYTOCHROME P450: AN EVALUATION OF FLUOROGENIC TO CONVENTIONAL SUBSTRATES by COHEN, Lawrence H, REMLEY, Michael J, RAUNIG, David, VAZ, Alfin D. N

“…Clinically observed drug interactions with cytochrome P450 (P450) enzymes have increased the need to assess drug interactions of new chemical entities early in…”
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A Simple Litmus Test for Aldehyde Oxidase Metabolism of Heteroarenes by O’Hara, Fionn, Burns, Aaron C, Collins, Michael R, Dalvie, Deepak, Ornelas, Martha A, Vaz, Alfin D. N, Fujiwara, Yuta, Baran, Phil S

“…The bioavailability of aromatic azaheterocyclic drugs can be affected by the activity of aldehyde oxidase (AO). Susceptibility to AO metabolism is difficult to…”
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BIOACTIVATION OF THE NONTRICYCLIC ANTIDEPRESSANT NEFAZODONE TO A REACTIVE QUINONE-IMINE SPECIES IN HUMAN LIVER MICROSOMES AND RECOMBINANT CYTOCHROME P450 3A4 by KALGUTKAR, Amit S, VAZ, Alfin D. N, HOP, Cornelis E. C. A, LAME, Mary E, HENNE, Kirk R, SOGLIA, John, ZHAO, Sabrina X, ABRAMOV, Yuri A, LOMBARDO, Franco, COLLIN, Claire, HENDSCH, Zachary S

“…The therapeutic benefits of the antidepressant nefazodone have been hampered by several cases of acute hepatotoxicity/liver failure. Although the mechanism of…”
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Epoxidation of Olefins by Cytochrome P450: Evidence from Site-Specific Mutagenesis for Hydroperoxo-Iron as an Electrophilic Oxidant by Alfin D. N. Vaz, McGinnity, Dermot F., Coon, Minor J.

“…P450 cytochromes (P450) catalyze many types of oxidative reactions, including the conversion of olefinic substrates to epoxides by oxygen insertion. In some…”
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Deuterium isotope effects on drug pharmacokinetics. I. System-dependent effects of specific deuteration with aldehyde oxidase cleared drugs by Sharma, Raman, Strelevitz, Timothy J, Gao, Hongying, Clark, Alan J, Schildknegt, Klaas, Obach, R Scott, Ripp, Sharon L, Spracklin, Douglas K, Tremaine, Larry M, Vaz, Alfin D N

“…The pharmacokinetic properties of drugs may be altered by kinetic deuterium isotope effects. With specifically deuterated model substrates and drugs…”
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On the Mechanism of Action of Cytochrome P450: Evaluation of Hydrogen Abstraction in Oxygen-Dependent Alcohol Oxidation by Vaz, Alfin D. N, Coon, Minor J

“…The mechanisms of oxidation of primary and secondary benzylic alcohols to the corresponding carbonyl compounds by purified rabbit liver cytochrome P450 forms…”
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Discrete Species of Activated Oxygen Yield Different Cytochrome P450 Heme Adducts from Aldehydes by Kuo, Chung-Liang, Raner, Gregory M, Vaz, Alfin D. N, Coon, Minor J

“…Aldehydes are known to inactivate cytochrome P450 in the reconstituted enzyme system containing NADPH and NADPH−cytochrome P450 reductase under aerobic…”
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A rapid and specific derivatization procedure to identify acyl-glucuronides by mass spectrometry by Vaz, Alfin D. N., Wang, Wei Wei, Bessire, Andrew J., Sharma, Raman, Hagen, Anne E.

“…A simple procedure is described to identify acyl‐glucuronides by coupled liquid chromatography/mass spectrometry after derivatization to a hydroxamic acid with…”
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Cytochrome P450-Catalyzed Hydroxylation of Mechanistic Probes that Distinguish between Radicals and Cations. Evidence for Cationic but Not for Radical Intermediates by Newcomb, Martin, Shen, Runnan, Choi, Seung-Yong, Toy, Patrick H, Hollenberg, Paul F, Vaz, Alfin D. N, Coon, Minor J

“…Oxidation of the mechanistic probes trans,trans-2-methoxy-3-phenylmethylcyclopropane and methylcubane by six cytochrome P450 isozymes has been studied. The…”
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In vitro metabolism studies on the isoxazole ring scission in the anti-inflammatory agent leflunomide to its active α-cyanoenol metabolite A771726: Mechanistic similarities with the cytochrome P450-catalyzed dehydration of aldoximes by KALGUTKAR, Amit S, NGUYEN, Hang T, VAZ, Alfin D. N, DOAN, Anke, DALVIE, Deepak K, MCLEOD, Dale G, MURRAY, John C

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Discovery of Azetidinyl Ketolides for the Treatment of Susceptible and Multidrug Resistant Community-Acquired Respiratory Tract Infections by Magee, Thomas V, Ripp, Sharon L, Li, Bryan, Buzon, Richard A, Chupak, Lou, Dougherty, Thomas J, Finegan, Steven M, Girard, Dennis, Hagen, Anne E, Falcone, Michael J, Farley, Kathleen A, Granskog, Karl, Hardink, Joel R, Huband, Michael D, Kamicker, Barbara J, Kaneko, Takushi, Knickerbocker, Michael J, Liras, Jennifer L, Marra, Andrea, Medina, Ivy, Nguyen, Thuy-Trinh, Noe, Mark C, Obach, R. Scott, O’Donnell, John P, Penzien, Joseph B, Reilly, Usa Datta, Schafer, John R, Shen, Yue, Stone, Gregory G, Strelevitz, Timothy J, Sun, Jianmin, Tait-Kamradt, Amelia, Vaz, Alfin D. N, Whipple, David A, Widlicka, Daniel W, Wishka, Donn G, Wolkowski, Joanna P, Flanagan, Mark E

“…Respiratory tract bacterial strains are becoming increasingly resistant to currently marketed macrolide antibiotics. The current alternative telithromycin (1)…”
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Olefin formation in the oxidative deformylation of aldehydes by cytochrome P-450. Mechanistic implications for catalysis by oxygen-derived peroxide by Vaz, Alfin D. N, Roberts, Elizabeth A, Coon, Minor J

“…We describe the cytochrome P-450 mediated oxidative deformylation of a xenobiotic aldehyde with introduction of unsaturation into the residual carbon framework…”
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Aromatization of a Bicyclic Steroid Analog, 3-Oxodecalin-4-ene-10-carboxaldehyde, by Liver Microsomal Cytochrome P450 2B4 by Vaz, Alfin D. N, Kessell, Kimberly J, Coon, Minor J

“…Several purified isoforms of microsomal cytochrome P450 were previously shown in this laboratory to catalyze the oxidative deformylation of a variety of alpha-…”
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The use of 18O-exchange and base-catalyzed N-dealkylation with liquid chromatography/tandem mass spectrometry to identify carbinolamide metabolites by Bessire, Andrew J., Vaz, Alfin D. N., Walker, Gregory S., Wang, Wei Wei, Sharma, Raman

“…Oxidation of N‐alkyl‐substituted amides is a common transformation observed in metabolism studies of drugs and other chemicals. Metabolism at the alpha carbon…”
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Peroxo-Iron and Oxenoid-Iron Species as Alternative Oxygenating Agents in Cytochrome P450-Catalyzed Reactions: Switching by Threonine-302 to Alanine Mutagenesis of Cytochrome P450 2B4 by Vaz, Alfin D. N., Pernecky, Steven J., Raner, Gregory M., Coon, Minor J.

“…Among biological catalysts, cytochrome P450 is unmatched in its multiplicity of isoforms, inducers, substrates, and types of chemical reactions catalyzed. In…”
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Two Distinct Electrophilic Oxidants Effect Hydroxyl- ation in Cytochrome P-450-Catalyzed Reactions by Toy, Patrick H, Newcomb, Martin, Coon, Minor J, Vaz, Alfin D. N

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Old yellow enzyme: Aromatization of cyclic enones and the mechanism of a novel dismutation reaction by Vaz, Alfin D. N, Chakraborty, Sumita, Massey, Vincent

“…The origin of charge transfer bands that develop on reaction of Old Yellow Enzyme with alpha,beta-unsaturated cyclic ketones such as 3-oxodecalin-4-ene (ODE,…”
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