The halogenated aromatic hydrocarbons (dibenzo-p-dioxins, dibenzofurans, azo[xy]benzenes and biphenyls), a group of toxic chemicals in the environment, (a) are approximate isostereomers; (b) produce a similar pattern of biologic responses and (c) appear to act by a common mechanism. These compounds reversibly bind to a soluble receptor protein to initiate a coordinate gene expression, analogous to the action of steroid hormones. This receptor controls two distinct and dissociable pleiotropic responses: (a) the induction of microsomal monooxygenase activity and other drug metabolizing enzymes and (b) morphologic (i.e. toxic) changes, many of which involve altered cell proliferation and/or differentiation in epithelial tissues.
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J Agric Food Chem
December 2024
Instituto de Química, Laboratório de Química Metodológica e Orgânica Sintética (LaQMOS), Universidade de Brasília, 70904-970 Brasília, DF, Brazil.
In this work, several imidazo[1,2-]pyridines were synthesized through the Groebke-Blackburn-Bienaymé three-component reaction (GBB-3CR), and their phytotoxicity was evaluated by the influence on the growth of wheat coleoptiles and three important agricultural seeds (, , and ) at test concentrations of 1000, 300, 100, 30, and 10 μM. A structure-activity relationship was established, showing the importance of halogen groups at the position of the attached aromatic ring and the presence of a cyclohexylamine group for greater activity. Post-modification of some GBB-3CR adducts was carried out, leading to imidazo[1,2-]pyridine-tetrazole hybrids, which were also evaluated in these bioassays.
View Article and Find Full Text PDFMethods Protoc
December 2024
Department of Natural Sciences, University of South Carolina Beaufort, 1 University Boulevard, Bluffton, SC 29909, USA.
The multifunctional catalytic hemoglobin from the terebellid polychaete , also named dehaloperoxidase (DHP), utilizes the typical oxygen transport function in addition to four observed activities involved in substrate oxidation. The multifunctional ability of DHP is presently a rare observation, and there exists a limitation for how novel dehaloperoxidases can be identified from macrobenthic infauna. In order to discover more infaunal DHP-bearing candidates, we have devised a facilitated method for an accurate taxonomic identification that places visual and molecular taxonomic approaches in parallel.
View Article and Find Full Text PDFSci Total Environ
December 2024
College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang 550025, China. Electronic address:
Disinfection by-products (DBPs), formed from biofilm extracellular polymeric substances (EPS) and organic matter during regular disinfection practices in drinking water distribution systems, poses a potential threat to drinking water safety. However, the diverse DBP formations induced by the intertwined algal organic matter (AOM) and bacterial EPS remains elusive. In this study, we show substantial variations in EPS and DBP formation patterns driven by AOM biosorption with divalent ions (Ca and Mg).
View Article and Find Full Text PDFACS ES T Water
December 2024
Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, South Carolina 29625, United States.
Seasonal algal blooms in surface waters can adversely impact drinking water quality. Oxidative treatment has been demonstrated as an effective measure for the removal of algal cells. However, this, in turn, leads to the release of algal organic matter (AOM).
View Article and Find Full Text PDFWater Res
December 2024
Department of Civil Engineering, University of Hong Kong, Pokfulam, Hong Kong, PR China.
The kinetics of polyamide membrane degradation by free chlorine and halide ions (Br and Cl) were innovatively evaluated based on physicochemical properties and filtration performance, using water/solute permeability coefficient in addition to bromide incorporation as important indicators. The reaction rate constants for the reduced water and HBO permeability coefficient were 1-2 orders of magnitude higher at 0-1 h than 1-10 h. N-bromination and bromination-promoted hydrolysis are dominant degradation mechanisms at 0-1 h (reflected by the breakage of hydrogen bond, the increased Ca binding content, and the increased charge density), and ring-bromination further occurs at 1-10 h (reflected by the disappearance or weakening of aromatic amide band and the nearly constant hydrogen bond).
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