Mechanism of the N-hydroxylation of primary and secondary amines by cytochrome P450.

abstract：:High-throughput screening (HTPS) assays to detect inhibitors of thyroperoxidase (TPO), the enzymatic catalyst for thyroid hormone (TH) synthesis, are not currently available. Herein, we describe the development of a HTPS TPO inhibition assay. Rat thyroid microsomes and a fluorescent peroxidase substrate, Amplex UltraR...

journal_title：Chemical research in toxicology

authors： Paul KB,Hedge JM,Rotroff DM,Hornung MW,Crofton KM,Simmons SO

更新日期：2014-03-17 00:00:00

abstract：:The reactions of calf thymus DNA with four 1,3-dialkyl-3-acyltriazenes were studied alone or in the presence of pig liver esterase in pH 7.4 phosphate buffer for varying lengths of time. The best alkylating agent in the absence of esterase was determined to be 1,3-dimethyl-3-carbethoxytriazene (DMC), followed in order...

journal_title：Chemical research in toxicology

authors： Kroeger-Koepke MB,Michejda CJ,Smith RH Jr

更新日期：1992-07-01 00:00:00

abstract：:Retinyl palmitate (RP) is frequently used as an ingredient in cosmetics and other retail products. We previously reported that, under UVA light irradiation, RP is facilely decomposed into multiple products, including anhydroretinol (AR) and 5,6-epoxyretinyl palmitate (5,6-epoxy-RP). We also determined that combined tr...

journal_title：Chemical research in toxicology

authors： Mei N,Xia Q,Chen L,Moore MM,Chen T,Fu PP

更新日期：2006-11-01 00:00:00

abstract：:N-Nitrosopyrrolidine (NPYR) is a well-established hepatocarcinogen in the rat. NPYR requires metabolic activation by cytochrome P450-catalyzed alpha-hydroxylation to express its carcinogenic activity. This produces alpha-hydroxyNPYR (2), which spontaneously ring opens to 4-oxobutanediazohydroxide (4), a highly reactiv...

journal_title：Chemical research in toxicology

authors： Wang M,Lao Y,Cheng G,Shi Y,Villalta PW,Hecht SS

更新日期：2007-04-01 00:00:00

abstract：:The toxicity of CuO nanoparticles (NPs) to human lung epithelial (A549) cells was investigated in this study. CuO NPs (10-100 mg/L) had significant toxicity to A549 cells, whereas CuO bulk particles (BPs) showed much lower toxicity (24 h IC(50), 58 and 15 mg/L for CuO BPs and NPs, respectively). Transmission electron ...

journal_title：Chemical research in toxicology

authors： Wang Z,Li N,Zhao J,White JC,Qu P,Xing B

更新日期：2012-07-16 00:00:00

abstract：:Our laboratory previously reported the identification and quantification of depurinating DNA adducts of dibenzo[a,l]pyrene (DB[a,l]P) in vitro, which comprise about 84% of all the DNA adducts that are formed [Li, K.-M., et al. (1995) Biochemistry 34, 8043-8049]. To determine a complete adduct profile and identify both...

journal_title：Chemical research in toxicology

authors： Devanesan P,Ariese F,Jankowiak R,Small GJ,Rogan EG,Cavalieri EL

更新日期：1999-09-01 00:00:00

abstract：:The deamination of DNA bases by three alpha-nitrosaminoaldehydes, butylethanalnitrosamine, methylethanalnitrosamine, and N-nitroso-2-hydroxymorpholine (NHMOR), the direct metabolite of potent animal carcinogen N-nitrosodiethanolamine, was demonstrated by a set of in vitro experiments. The deamination of guanine, adeni...

journal_title：Chemical research in toxicology

authors： Park M,Loeppky RN

更新日期：2000-02-01 00:00:00

abstract：:The transforming growth factor beta (TGFβ) superfamily of secreted signaling molecules and their cognate receptors regulate cell fate and behaviors relevant to many developmental and disease processes. Disruption of TGFβ signaling during embryonic development can, for example, affect morphogenesis and differentiation ...

journal_title：Chemical research in toxicology

authors： Wei Z,Sakamuru S,Zhang L,Zhao J,Huang R,Kleinstreuer NC,Chen Y,Shu Y,Knudsen TB,Xia M

更新日期：2019-12-16 00:00:00

abstract：:Nitric oxide (NO(•); nitrogen monoxide) is known to be a critical regulator of cell and tissue function through mechanisms that utilize its unique physicochemical properties as a small and uncharged free radical with limited reactivity. Here, the basic chemistry and biochemistry of NO(•) are summarized through the des...

journal_title：Chemical research in toxicology

authors： Toledo JC Jr,Augusto O

更新日期：2012-05-21 00:00:00

abstract：:Nuclear magnetic resonance (NMR) spectroscopy has traditionally been considered as an indispensable tool in elucidating structures of metabolites. With the advent of Fourier transform (FT) spectrometers, along with improvements in software and hardware (such as high-field magnets, cryoprobes, versatile pulse sequences...

journal_title：Chemical research in toxicology

authors： Espina R,Yu L,Wang J,Tong Z,Vashishtha S,Talaat R,Scatina J,Mutlib A

更新日期：2009-02-01 00:00:00

abstract：:Nicking of the DNA strand immediately upstream of an internal abasic (AP) site produces 5'-terminal abasic (dRp) DNA. Both the intact and the nicked abasic species are reactive intermediates along the DNA base excision repair (BER) pathway and can be derailed by side reactions. Aberrant accumulation of the 5'-terminal...

journal_title：Chemical research in toxicology

authors： Admiraal SJ,O'Brien PJ

更新日期：2017-06-19 00:00:00

abstract：:Estrogens, including the natural hormones estrone (E(1)) and estradiol (E(2)), are thought to be involved in tumor induction. Specifically, catechol estrogen quinones (CEQs) derived from the catechol estrogens 4-hydroxyestrone (4-OHE(1)) and 4-hydroxyestradiol (4-OHE(2)) react with DNA and form DNA adducts (Cavalieri,...

journal_title：Chemical research in toxicology

authors： Jankowiak R,Markushin Y,Cavalieri EL,Small GJ

更新日期：2003-03-01 00:00:00

abstract：:The Adverse Outcome Pathway (AOP) paradigm details the existing knowledge that links the initial interaction between a chemical and a biological system, termed the molecular initiating event (MIE), through a series of intermediate events, to an adverse effect. An important example of a well-defined MIE is the formatio...

journal_title：Chemical research in toxicology

authors： Ebbrell DJ,Madden JC,Cronin MT,Schultz TW,Enoch SJ

更新日期：2016-06-20 00:00:00

abstract：:The major plant growth regulator ethephon degrades to ethylene and phosphate in aqueous solutions and plants and is spontaneously activated to a butyrylcholinesterase (BChE) inhibitor in alkaline solutions and animal tissues. In the present (31)P NMR kinetic study of the reactions of ethephon in pH 7.4 carbonate buffe...

journal_title：Chemical research in toxicology

authors： Lantz SR,Casida JE

更新日期：2013-09-16 00:00:00

abstract：:Previous studies suggested that lamotrigene (LTG) underwent bioactivation to a reactive aryl epoxide intermediate in rats. Nevertheless, definitive structures of these thioether conjugates, which are often needed to substantiate the mechanism of bioactivation and identity of reactive intermediate(s), were not fully es...

journal_title：Chemical research in toxicology

authors： Chen H,Grover S,Yu L,Walker G,Mutlib A

更新日期：2010-01-01 00:00:00

abstract：:Topoisomerase II is an essential nuclear enzyme involved in regulating DNA topology to facilitate replication and cell division. Disruption of topoisomerase II function by chemotherapeutic agents is in use as an effective strategy to fight cancer. Etoposide is an anticancer therapeutic that disrupts the catalytic cycl...

journal_title：Chemical research in toxicology

authors： Gibson EG,King MM,Mercer SL,Deweese JE

更新日期：2016-09-19 00:00:00

abstract：:Docosahexaenoic acid (DHA) is a semiessential polyunsaturated fatty acid (PUFA) for eukaryotic cells that is found in natural sources such as fish and algal oils and widely used as an ingredient for omega-3 containing foods or supplements. DHA effects are connected to its natural structure with six cis double bonds, b...

journal_title：Chemical research in toxicology

authors： Menounou G,Giacometti G,Scanferlato R,Dambruoso P,Sansone A,Tueros I,Amézaga J,Chatgilialoglu C,Ferreri C

更新日期：2018-03-19 00:00:00

abstract：:The mechanisms underlying aryl hydrocarbon receptor (AHR) activation by agonists and circumstances that increase the sensitivity toward agonists and AHR inhibition by antagonists are diverse and still not fully understood. AHR antagonist, 2-methyl-2 H-pyrazole-3-carboxylic acid (2-methyl-4- o-tolylazo-phenyl)-amide, C...

journal_title：Chemical research in toxicology

authors： Mohammadi-Bardbori A,Omidi M,Arabnezhad MR

更新日期：2019-04-15 00:00:00

abstract：:In recent years, there has been an increase in the production of shellfish and in global demand for seafood as nutritious and healthy food. Unfortunately, a significant number of incidences of shellfish poisoning occur worldwide, and microalgae that produce phycotoxins are responsible for most of these. Phycotoxins in...

journal_title：Chemical research in toxicology

authors： Otero A,Chapela MJ,Atanassova M,Vieites JM,Cabado AG

更新日期：2011-11-21 00:00:00

abstract：:Thalidomide is an infamous teratogen and it is continuously being explored for its anticancer properties. Fibroblast growth factor receptors (FGFRs) are implicated in embryo development and cancer pathophysiology. With striking similarities observed between FGFR implicated conditions and thalidomide embryopathy, we hy...

journal_title：Chemical research in toxicology

authors： Sundaresan L,Kumar P,Manivannan J,Balaguru UM,Kasiviswanathan D,Veeriah V,Anishetty S,Chatterjee S

更新日期：2019-04-15 00:00:00

abstract：:The effects of hepatotoxic doses of acetaminophen on tissue concentrations of CoA in the thiol form (CoASH) and as the corresponding mixed disulfide with GSH (CoASSG) were determined to test the hypotheses that early oxidant effects of acetaminophen are expressed principally in the mitochondrial compartment and that o...

journal_title：Chemical research in toxicology

authors： Rogers LK,Valentine CJ,Szczpyka M,Smith CV

更新日期：2000-09-01 00:00:00

abstract：:The present study describes a novel integrated approach for rapid analysis of reactive metabolites with a linear ion trap mass spectrometer (LTQ). In this approach, an isotope pattern-dependent scanning method was applied to the data acquisition of glutathione (GSH)-trapped reactive metabolites. Recorded full-scan MS ...

journal_title：Chemical research in toxicology

authors： Ma L,Wen B,Ruan Q,Zhu M

更新日期：2008-07-01 00:00:00

abstract：:Aminoglutethimide (AMG) is an aromatic amine aromatase inhibitor associated with a high incidence of idiosyncratic blood dyscrasias, especially agranulocytosis. Animal models of idiosyncratic drug reactions (IDRs) represent essential tools to study these reactions; however, there is currently no valid model of idiosyn...

journal_title：Chemical research in toxicology

authors： Ng W,Uetrecht J

更新日期：2013-08-19 00:00:00

abstract：:Derivatives of methyl 3-(1-methyl-5-(1-methyl-5-(propylcarbamoyl)-1H-pyrrol-3-ylcarbamoyl)-1H-pyrrol-3-ylamino)-3-oxopropane-1-sulfonate (1), a peptide-based DNA minor groove binding methylating agent, were synthesized and characterized. In all cases, the N-terminus was appended with an O-methyl sulfonate ester, while...

journal_title：Chemical research in toxicology

authors： Iyer P,Srinivasan A,Singh SK,Mascara GP,Zayitova S,Sidone B,Fouquerel E,Svilar D,Sobol RW,Bobola MS,Silber JR,Gold B

更新日期：2013-01-18 00:00:00

abstract：:Taconite mining involves potential exposure to non-asbestiform amphibole mineral fiber. More recent studies have demonstrated increased mortality from respiratory cancers and heart disease among workers in the taconite industry. This finding is not consistent with recent exposure assessment findings, nor is the toxico...

journal_title：Chemical research in toxicology

authors： Mandel JH,Ramachandran G,Alexander BH

更新日期：2016-02-15 00:00:00

abstract：:Reactive oxygen species (ROS), which can be produced during normal aerobic metabolism, can induce the formation of tandem DNA lesions, including 8,5'-cyclo-2'-deoxyadenosine (cyclo-dA) and 8,5'-cyclo-2'-deoxyguanosine (cyclo-dG). Previous studies have shown that cyclo-dA and cyclo-dG accumulate in cells and can block ...

journal_title：Chemical research in toxicology

authors： Swanson AL,Wang J,Wang Y

更新日期：2012-08-20 00:00:00

abstract：:Spin-trapping with 5,5-dimethyl-1-pyrroline 1-oxide (DMPO) was used to demonstrate that 3-nitrotyrosine (nitrotyrosine) promotes the formation of substantial amounts of reactive oxygen species (O2.- and *OH), when incubated with NAD(H)-cytochrome c reductase and a corresponding electron donor. Spin adduct formation is...

journal_title：Chemical research in toxicology

authors： Krainev AG,Williams TD,Bigelow DJ

更新日期：1998-05-01 00:00:00

abstract：:Because the manganese-based contrast agents used in magnetic, resonance imaging are unstable in vivo, some concern exists about the potential toxicity coming from the Mn2+ released by the complexes. This potential problem arises because the manganese is known to accumulate in the brain of people intoxicated by this me...

journal_title：Chemical research in toxicology

authors： Gallez B,Baudelet C,Adline J,Geurts M,Delzenne N

更新日期：1997-04-01 00:00:00

abstract：:Exposure to the tobacco-related nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N'-nitrosonornicotine is carcinogenic to humans. Metabolic activation of NNK leads to the formation of DNA adducts, which play a critical role in NNK carcinogenesis. Adducts specific to NNK result from covalent linkag...

journal_title：Chemical research in toxicology

authors： Sturla SJ,Scott J,Lao Y,Hecht SS,Villalta PW

更新日期：2005-06-01 00:00:00

abstract：:Implementation of the Clinical Data Interchange Standards Consortium (CDISC)'s Standard for Exchange of Nonclinical Data (SEND) by the United States Food and Drug Administration Center for Drug Evaluation and Research (US FDA CDER) has created large quantities of SEND data sets and a tremendous opportunity to apply la...

journal_title：Chemical research in toxicology

authors： Carfagna MA,Anderson J,Eley C,Fukushima T,Horvath J,Houser W,Larsen B,Page T,Russo D,Sloan C,Snyder K,Thompson R,Ullmann G,Whittaker M

更新日期：2020-12-16 00:00:00