Micro-injection of, or incubation with okadaic acid (OA), a specific phosphatase inhibitor, can induce formation of maturation-promoting factor (MPF) and germinal vesicle breakdown (GVBD) in Xenopus laevis oocytes. Comparison of the dose-response curves of OA on maturation, isolated enzymes and phosphatase activities in crude oocyte preparations suggests that inhibition of both polycation-stimulated (PCS) and ATP,Mg-dependent (AMD) phosphatases is sufficient but requires that a critical phosphorylation level is attained of one or several of their substrates, resulting in the formation of active MPF and meiotic maturation.
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http://dx.doi.org/10.1016/0014-5793(89)80198-x | DOI Listing |
J Hazard Mater
December 2024
Center for Marine Studies, Federal University of Paraná, Pontal do Paraná, Brazil.
Microplastics (MP) are suitable substrates for the colonization of harmful microalgal cells and the adsorption of their lipophilic compounds including phycotoxins. Moreover, such interactions likely change as physical-chemical characteristics of the MP surface are gradually modified during plastic degradation in aquatic environments. Using a combination of innovative laboratory experiments, this study systematically investigated, for the first time, the influence of various MP characteristics (polymeric composition, shape, size, and/or surface roughness) on its capacity to carry both living harmful algal cells and dissolved phycotoxins.
View Article and Find Full Text PDFMar Environ Res
December 2024
Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
Lipophilic phycotoxins (LPTs) are toxic and lipophilic secondary metabolites produced by toxic microalgae, which pose a serious threat to marine shellfish culture industries. LPTs were systematically investigated in bottom seawater, suspended particulate matter (SPM), sediment, and sediment porewater of Laizhou Bay, a typical mariculture bay in China, to understand the chemical diversity and environment behaviors of LPTs in the benthic environments. Okadaic acid (OA), pectenotoxin-2 (PTX2), dinophysistoxin-1 (DTX1), azaspiracid-2 (AZA2), gymnodimine (GYM), pectenotoxin-2 seco acid (PTX2 SA), 7-epi- pectenotoxin-2 seco acid (7-epi-PTX2 SA), 13-desmethylspirolide C (SPX1), yessotoxin (YTX) and homo YTX (h-YTX) were detected in the benthic environment of Laizhou Bay in spring, indicating that LPTs are rich in chemical diversity.
View Article and Find Full Text PDFHarmful Algae
January 2025
School of Marine and Atmospheric Sciences, Stony Brook University, Southampton, NY, United States. Electronic address:
Pharmaceuticals (Basel)
November 2024
Pharmaceutical and Health Science Department, Pharmacy Faculty, San Pablo-CEU University, CEU Universities, Urbanización Montepríncipe Boadilla del Monte, 28660 Madrid, Spain.
: berries are edible fruits from the Iberian Atlantic coast, characterized by a rich polyphenolic composition, which endows their juice with potential protective effects against neurodegeneration. This study aimed to evaluate the potential of the relatively lesser-known berries as a novel neuroprotective agent against neurodegenerative diseases. : The phenolic compounds of the juice were characterized using UHPLC-HRMS (Orbitrap).
View Article and Find Full Text PDFToxins (Basel)
November 2024
Department of Chemistry, Alfaisal University, Al Zahrawi Street, Al Maather, Al Takhassusi Rd, Riyadh 11355, Saudi Arabia.
In this report, we describe a fluorescent assay for the detection of six marine toxins in water. The mechanism of detection is based on a duplex-to-complex structure-switching approach. The six aptamers specific to the targeted cyanotoxins were conjugated to a fluorescent dye, carboxyfluorescein (FAM).
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