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Environmental Science & Technology Apr 2005Amitrole (ATz, 3-amino-1H-1,2,4-triazole) is a widely employed herbicide with strong estrogenic activity that can lead to abnormalities of the thyroid gland and can... (Comparative Study)
Comparative Study
Formation of refractory ring-expanded triazine intermediates during the photocatalyzed mineralization of the endocrine disruptor amitrole and related triazole derivatives at UV-irradiated TiO2/H2O interfaces.
Amitrole (ATz, 3-amino-1H-1,2,4-triazole) is a widely employed herbicide with strong estrogenic activity that can lead to abnormalities of the thyroid gland and can cause mutations. The photocatalytic transformation of ATz was carried out at the UV-irradiated TiO2/H2O interface, along with the triazole derivatives Tz (1H-1,2,4-triazole) and DaTz (3,5-diamino-1H-1,2,4-triazole) to assess the decomposition of these herbicides, to identify intermediates, and to elucidate some mechanistic details of the ATz degradation. Conversion of the nitrogens of these triazoles to NH4+ and/ or NO3- ions occurs competitively and depends on the number of amine functions on the five-membered triazole rings. Photomineralization of the substrates in terms of loss of nitrogen to NH4+/NO3- was rather low (ca. 25-40%) for each of the triazoles, whereas evolution of CO2 (loss of TOC) was more significant (60-70%), indicating considerable retention of nitrogen in the intermediate products. UV-Vis spectroscopy, TOC assays, FT-IR spectroscopy, proton NMR spectrometry, electrospray LC-MS, and molecular orbital calculations were brought to bear in assessing the temporal course of the photocatalyzed process(es). Results show that after cleavage of the triazole ring, the various intermediate fragments recombine to yield ring-expanded six-membered triazine intermediates, which slowly degrade to give the refractory cyanuric acid under the conditions used.
Topics: Amitrole; Catalysis; Chromatography, Liquid; Hydrogen-Ion Concentration; Magnetic Resonance Spectroscopy; Mass Spectrometry; Nitrogen Compounds; Photochemistry; Spectroscopy, Fourier Transform Infrared; Triazenes; Triazoles; Ultraviolet Rays; Water Pollution, Chemical
PubMed: 15871271
DOI: 10.1021/es049791l -
Journal of Chromatography. A Oct 2004This study used capillary electrophoresis (CE) to investigate the simultaneous separation and on-line concentration of five pesticides: amitrole (AMT), carbendazim...
Simultaneous separation and on-line concentration of amitrole and benzimidazole pesticides by capillary electrophoresis with a volatile migration buffer applicable to mass spectrometric detection.
This study used capillary electrophoresis (CE) to investigate the simultaneous separation and on-line concentration of five pesticides: amitrole (AMT), carbendazim (MBC), 2-aminobenzimidazole (ABI), thiabendazole (TBZ) and 1,2-diaminobenzene (DAB). A volatile migration buffer was used for the investigation because of the applicability to mass spectrometric (MS) detection. They were separated completely at pH 4.0 as a result of changing pH using formic acid-ammonium formate buffer. Values of the dissociation constant for MBC and DAB estimated from the changes in the mobility with pH showed good agreement with values in the literature. Dissociation constants for AMT and TBZ were estimated. Limits of detection (LODs) for the analytes were on the ppm level with UV detection under the optimized separation condition. On-line concentration by simple stacking mode was not effective except to 2-aminobenzimidazole because of the peak tailing. The addition of formic acid to sample matrix improved the peak shapes. That improvement may be attributed to transient isotachophoretic effect. The concentration factors obtained from the comparison of the LODs were in the range of 7.6-27-fold. This concentration method was applied preliminarily to CE with MS detection.
Topics: Amitrole; Benzimidazoles; Buffers; Electrophoresis, Capillary; Mass Spectrometry; Pesticides; Sensitivity and Specificity; Spectrophotometry, Ultraviolet; Volatilization
PubMed: 15532587
DOI: 10.1016/j.chroma.2004.05.050 -
International Journal of Clinical... Jan 1981The pharmacokinetics of amitryptyline (AMI) have been evaluated in six healthy elderly volunteers (72-83 years of age) after a single dose of 125 mg of AMI-HCl. AMI was...
The pharmacokinetics of amitryptyline (AMI) have been evaluated in six healthy elderly volunteers (72-83 years of age) after a single dose of 125 mg of AMI-HCl. AMI was absorbed rather slowly (mean peak time 10.4 +/- 1.6 hrs) but very efficiently (F: 0.59-0.75). The rate of formation of nortriptyline (NT) as well as the appearance clearance values (0.18-0.45 l/h/kg) of AMI were significantly lower than those previously described for younger subjects. Reversible alterating ECG were observed in 5 cases concomitantly with AMI peak plasma concentrations. The results indicate the desirability of reduced and/or divided daily doses of AMI in the elderly.
Topics: Aged; Amitriptyline; Electrocardiography; Hemodynamics; Humans; Kinetics; Nortriptyline
PubMed: 7203728
DOI: No ID Found -
Mutation Research Sep 1992Amitrole is a herbicide which has been found to induce thyroid and liver tumours in rodents, yet demonstrates limited genotoxic activity. The lack of mutagenicity of... (Comparative Study)
Comparative Study
Amitrole is a herbicide which has been found to induce thyroid and liver tumours in rodents, yet demonstrates limited genotoxic activity. The lack of mutagenicity of this compound in Salmonella typhimurium when employing a standard liver microsomal fraction, combined with evidence of activation of amitrole by peroxidases, warranted an investigation employing this other pathway of metabolic activation. Using prostaglandin H synthase as the activating system, the aromatic amine 2-aminofluorene provided a convenient positive control for optimisation of the metabolising system. Under such conditions, amitrole did not induce elevated numbers of revertant colonies in Salmonella typhimurium TA98, neither did it display evidence of interference with histidine biosynthesis as had been reported. Amitrole also remained nonmutagenic when preincubated at varying pHs. Thus, it has been shown that the alternative activation system, prostaglandin H synthase, does not produce metabolites which are mutagenic in the Ames test.
Topics: Amitrole; Biotransformation; Fluorenes; Mutagenicity Tests; Mutagens; Prostaglandin-Endoperoxide Synthases; Salmonella typhimurium
PubMed: 1380667
DOI: 10.1016/0165-7992(92)90115-x -
Mutation Research Jul 1976Amitrole was highly toxic at early larval stages of Drosophila (LD50 is 40 ppm in medium). Toxicity of amitrole was also revealed by prolongation of development time...
Amitrole was highly toxic at early larval stages of Drosophila (LD50 is 40 ppm in medium). Toxicity of amitrole was also revealed by prolongation of development time even at 10 ppm. However, no mutagenic effects of amitrole were observed either in the sex chromosome non-disjunction test (females reared on medium containing amitrole at 10 ppm) or in the sex-linked recessive lethal test (males reared on medium containing amitrole at 10 ppm).
Topics: Amitrole; Animals; Chromosome Aberrations; Drosophila melanogaster; Female; Genes, Lethal; Genes, Recessive; Genetic Linkage; Male; Mutagens; Sex Chromosomes; Triazoles
PubMed: 822329
DOI: 10.1016/0165-1218(76)90043-4 -
Journal of the American Society For... Mar 2022Workplace chemical exposures are a major source of occupational injury. Although over half of these are skin exposures, exposomics research often focuses on chemical...
Workplace chemical exposures are a major source of occupational injury. Although over half of these are skin exposures, exposomics research often focuses on chemical levels in the air or in worker biofluids such as blood and urine. Until now, one limitation has been the lack of methods to quantitatively measure surface chemical transfer. Outside the realm of harmful chemicals, the small molecules we leave behind on surfaces can also reveal important aspects of human behavior. In this study, we developed a swab-based quantitative approach to determine small molecule concentrations across common surfaces. We demonstrate its utility using one drug, cyclobenzaprine, on metal surfaces, and two human-derived metabolites, carnitine and phenylacetylglutamine, on four common surfaces: linoleum flooring, plastified laboratory workbench, metal, and Plexiglas. We observed peak areas proportional to surface analyte concentrations at 45 min and 1 week after deposition, enabling quantification of molecule abundance on workplace built environment surfaces. In contrast, this method was unsuitable for analysis of oleanolic acid, for which we did not observe a strong linear proportional relationship following swab-based recovery from surfaces. Overall, this method paves the way for future quantitative exposomics studies in analyte-specific and surface-specific frameworks.
Topics: Amitriptyline; Carnitine; Environmental Exposure; Environmental Monitoring; Glutamine; Humans; Workplace
PubMed: 35084848
DOI: 10.1021/jasms.1c00263 -
Archives of Neurology Nov 1979In a controlled trial of amitriptyline hydrochloride in migraine prophylaxis, 100 patients received placebo for a four-week baseline period and then were randomized in... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
In a controlled trial of amitriptyline hydrochloride in migraine prophylaxis, 100 patients received placebo for a four-week baseline period and then were randomized in double-blind fashion to therapy with amitriptyline (47 subjects) or placebo (53 subjects) for another four to eight weeks. Subjects received up to four 25-mg tablets of amitriptyline hydrochloride or identical placebo per day. Comparing the first and second four-week periods for each patient, the conditions of 55.3% of amitriptyline subjects as opposed to 34.0% of placebo subjects were greater than or equal to 50% improved and the difference between amitriptyline and placebo response rates was significant (P less than .05). Nondepressed subjects with severe migraine and depressed subjects with less severe migraine responded best to amitriptyline, whereas depressed subjects with severe migraine had little headache relief. Amitritryline is an effective antimigraine agent and the antimigraine effect seems relatively independent of antidepressant activity.
Topics: Amitriptyline; Depression; Double-Blind Method; Humans; Migraine Disorders
PubMed: 508127
DOI: 10.1001/archneur.1979.00500470065013 -
Biochemical Pharmacology Oct 1986
Topics: Amitrole; Animals; Catalase; Cattle; Liver; Triazoles
PubMed: 3768046
DOI: 10.1016/0006-2952(86)90639-8 -
Clinical Pharmacology and Therapeutics Jul 1980Amitriptyline (AT) and its demethyl metabolite nortriptyline (NT) were given orally and intramuscularly to 6 normal subjects, and the areas under the blood...
Amitriptyline (AT) and its demethyl metabolite nortriptyline (NT) were given orally and intramuscularly to 6 normal subjects, and the areas under the blood concentration--time curves (AUC) were calculated. The mean unbound fraction of AT and NT in plasma was 5.4% and 8.3%, respectively. The blood-plasma ratio of NT was nearly double that of AT, which was close to unity. The mean systemic availability of oral relative to intramuscular AT and NT was 43% and 61%. The calculated mean oral blood clearance of AT as measured by dose (oral)/AUC was 1.6 1/min. The demethylation of orally administered AT varied considerably between the 6 individuals (from 25% to 89%) and correlated with oral drug clearance. Demethylation was estimated from the AUC applied to the NT metabolite. The estimated oral clearance of AT from demethylation ranged from 0.21 to 1.80 1/min.
Topics: Administration, Oral; Adult; Amitriptyline; Dealkylation; Humans; Hydroxylation; Individuality; Injections, Intramuscular; Male; Metabolic Clearance Rate
PubMed: 7389249
DOI: 10.1038/clpt.1980.140 -
The American Journal of Psychiatry Apr 1979
Topics: Amitriptyline; Depression; Humans; Liver; Male; Middle Aged; Nortriptyline
PubMed: 426118
DOI: No ID Found