Percorrer por autor "Gomes, Isa D. L."
A mostrar 1 - 2 de 2
Resultados por página
Opções de ordenação
- Effects of Barcelona harbor sediments in biological responses of the polychaete Capitella teletaPublication . Gomes, Isa D. L.; Lemos, Marco F. L.; Soares, Amadeu M. V. M.; Díez, Sergi; Barata, Carlos; Faria, MelissaMarine ecosystems are increasingly exposed to a multitude of anthropogenic contaminants. Harbor environments are permanently subjected to such contaminants and bottomsediments are considered as the final repository. Filter-feeding and burrowing organisms, such as some polychaete communities, are among the most exposed organisms. This study aimed to assess the toxicity of Barcelona harbor sediments to the polychaete Capitella teleta by assessing and linking individual-level responses such as body weight (growth) and egestion rate (feeding) with subcellular-level responses including antioxidant (catalase and superoxide dismutase) and neurotransmission related (acetyl cholinesterase) enzyme activities. Sedimentswere collected fromthree different locations of the Barcelona (Spain) harbor with a positive gradient of metallic and organochlorine pollution from the mouth of the harbor towards the innermost zone. Sub-cellular and individual behavior of C. teleta exposed to Barcelona harbor sediments allowed the discrimination of toxic responses across sediments. Behavior responses were better correlated to chemical contamination than those of biomarkers. Harbor sediments produced neurotoxicity, promoted oxidative stress and reduced egestion and growth rates in exposed worms. These results indicate that biological responses of C. teleta worm can be used as early-warning tools to assess pollution effects on marine soft-bottom macrobenthonic communities.
- The use of cholinesterase as potential biomarker: In vitro characterization in the polychaete Capitella teletaPublication . Gomes, Isa D. L.; Lemos, Marco F. L.; Soares. Amadeu M. V. M.; Barata, Carlos; Faria, MelissaThe ecological relevance of polychaetes coupled with their easy culture and maintenance in the laboratory, has led them to become increasingly used in marine ecotoxicological studies, raising the need to validate frequently applied monitoring tools at various biological levels. The present study was aimed to characterize the cholinesterases (ChE) activity in the polychaete Capitella teleta, using three substrates (acetylthiocholine iodide, propionylthiocholine iodide, and S-butyrylthiocholine iodide) and four known inhibitors (eserine hemisulfate, BW284c51, iso-OMPA and chlorpyrifos-oxon). Results showed that most of the measured cholinesterase activity was acetylcholinesterase (AChE). Inhibition of enzyme kinetic experiments denoted that sensitivity of C. teleta’s ChE to the organophosphorous metabolite chlorpyrifos-oxon (IC50 = 60.72 nM) was analogous to some fish species. This study highlights the relevance of ChE characterization before its use as a biomarker in ecotoxicology and biomonitoring studies.