The emerging paradigm on plastic pollution in marine environments is that microsize particles (MPs) have far more subtle effects than bigger fragments, given their size range overlapping with that of particles ingested by filter-feeders. The impacts include gut blockage, altered feeding and energy allocation, with knock-on effects on widespread physiological processes. This study investigated whether ingestion of polystyrene MPs (PS-MPs) triggers protective processes in marine mussels. The Multixenobiotic resistance (MXR) system is a cytoprotective mechanism acting as an active barrier against harmful xenobiotics and a route of metabolite detoxification. Both larvae and adults were employed in laboratory experiments with different concentrations of 3-μm PS-MPs (larvae), and 3-μm and 45-μm PS-MPs (adults) matching size range of planktonic food through the mussel lifecycle. Embryos grown in the presence of 3-μm PS-MPs showed significant reduction of MXR activity and down-regulation of ABCB and ABCC transcripts encoding the two main MXR-related transporters P-glycoprotein and the Multidrug resistance-related protein, respectively. In adults, effects of PS-MPs were assessed in haemocytes and gills, which showed different modulation of MXR activity and ABCB/ABCC expression according to MP size (haemocyte and gills) or particle concentration (haemocyte). These data showed that modulation of MXR activity is part of a generalized response triggered by particle ingestion.
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http://dx.doi.org/10.1016/j.cbpc.2019.02.005 | DOI Listing |
Sci Total Environ
January 2025
Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 16419, South Korea. Electronic address:
This study compared the toxicological effects of environmentally relevant microplastics (MPs) on the marine rotifer Brachionus plicatilis, focusing on MPs derived from various sources, including fossil fuel-based low-density polyethylene, bio-based polylactic acid (PLA), biodegradable poly(butylene adipate-co-terephthalate), and a novel PLA modified with β-cyclodextrin. We assessed in vivo effects such as reproductive output and mortality, alongside in vitro oxidative stress responses, including oxidative stress, antioxidant enzyme activities, and activation of the mitogen-activated protein kinase (MAPK) signaling pathway and the multixenobiotic resistance (MXR) system. Reproductive output and lifespan reduced significantly across all MP types, ranging from 0.
View Article and Find Full Text PDFActa Psychol (Amst)
November 2024
Tianjin Normal University, China. Electronic address:
This article investigates whether English positive-negative alternating causal clauses and active-passive alternating syntactic structures make a difference in social event attribution of Chinese-L1 English-L2 learners. Results of sentence completion tasks show that there is no across-the-board language effect on attribution tendencies to the patient, the agent and the interactive parties, which are the constituents of the target sentences, but passive structures induce more attribution to the patient than its counterparts, and that L2 learners exhibit a gradience of attribution preferences for the patient, followed by the agent and the interactive parties in whichever clause or syntactic conditions. The causal reasoning patterns found in this study failed to support the claim of Linguistic Relativity, while validating the hypothesis regarding the patient-directed Causal Asymmetry Bias.
View Article and Find Full Text PDFChemistry
January 2025
Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR.
The activation of various homopropargylic pyridines by cis-[Ru/Os(dppm)Cl] (dppm=1,1-bis(diphenylphosphino)methane) has previously been shown to generate a diverse array of metallacycles and metalated heterocyclic complexes. However, a minor structural modification of introducing a halide onto the pyridyl group of the alkyne substrate resulted in the formation of unprecedented Ru(II)/Os(II)-haloquinolizine complexes. These complexes display (1) κ(X,C)-haloquinolizine chelates arising from the cycloisomerization of HC≡CC(OH)(CH(6-X-2-py))(Ph) on [Ru/Os(dppm)] moieties via a vinylidene pathway, (2) five-membered Ru/Os-X-C-N-C rings (X=F, Cl, Br) ortho- and peri-fused to quinolizinium skeletons, and (3) uncommon M-X-R bonding interactions that are atypical in coordination complexes.
View Article and Find Full Text PDFEcotoxicol Environ Saf
November 2024
Department of Biotechnology, College of Convergence Engineering, Sangmyung University, Seoul 03016, Republic of Korea. Electronic address:
Due to their worldwide distribution and persistence, mercury (Hg), and nano- and microplastics (NMPs) pose major threats to global ocean ecosystems. Hg and NMPs co-exist in the ocean and can interact with each other. However, information on the toxicity of this interaction to marine biota remains limited.
View Article and Find Full Text PDFFront Pharmacol
August 2024
Department Ecotoxicology, Helmholtz Centre for Environmental Research-UFZ, Leipzig, Germany.
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