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.

Download full-text PDF

Source

Publication Analysis

Top Keywords

halogenated aromatic
8
aromatic hydrocarbons
8
studies mechanism
4
mechanism action
4
action halogenated
4
hydrocarbons halogenated
4
hydrocarbons dibenzo-p-dioxins
4
dibenzo-p-dioxins dibenzofurans
4
dibenzofurans azo[xy]benzenes
4
azo[xy]benzenes biphenyls
4

Similar Publications

Phytotoxicity Study of (Amino)imidazo[1,2-]pyridine Derivatives Toward the Control of , , and Weeds.

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 PDF

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 PDF

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 PDF

Molecular Alterations of Algal Organic Matter in Oxidation Processes: Implications to the Formation of Disinfection Products.

ACS 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 PDF

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).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!