Microplastics in Cuban freshwaters: Diversity, temporal changes, and effects on extracellular enzymatic activity.

Plastics, as synthetic polymers, are emerging contaminants that can harm organisms and ecosystems. This study investigates the presence of microplastics in sediments of two rivers in western Cuba, assessing their temporal variability, diversity, and characterizing the types of microplastics in these ecosystems. Additionally, the study examines the relationship between microplastic concentrations, the extracellular enzymatic activity of benthic microbial communities, and nutrient levels in sediments.

Use of a nanoplastic carrier for assessing the aquatic toxicity of an organo-phosphite polymer additive.

This work reports the production of nanoplastics (NPs) from polypropylene (PP) free of the antioxidant Irgafos® 168 (IRG) and alkane oligomers (ALK). PP pellets were milled into a powder with particle sizes in the 100-500 μm range. Additives and oligomers were removed using dichloromethane, and the powder exposed to UV irradiation, followed by filtration through 1 μm filters.

Inhibiting SARS-CoV-2 viral entry by targeting spike:ACE2 interaction with -modified quercetin derivatives.

The cell entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is mediated by the interaction between the receptor-binding domain of its spike (S) protein and human angiotensin-converting enzyme 2 (ACE2). Quercetin, a flavonoid found abundantly in plants, shows potential as a SARS-CoV-2 S:ACE2 inhibitor but is known to have low bioavailability. Modification of quercetin by capping its hydroxyl moieties could enhance the metabolic stability, solubility, and bioavailability, and reduce toxicity.

The potential use of birds as bioindicators of suspended atmospheric microplastics and artificial fibers.

Microplastics (MPs) and artificial fibers (AFs) have been detected suspended tens of meters above ground level in the atmosphere, yet empirical data on them remain scarce. This study aimed to investigate the presence of MPs and AFs in the digestive and respiratory systems of two abundant bird species, the Common House Martin (Delichon urbicum) and the Common Swift (Apus apus), within the Community of Madrid, Spain. Given that these birds spend the majority of their lives airborne, engaging in activities such as mating and sleeping during flight, the research sought to assess the potential of using these bird species as bioindicators for suspended atmospheric MPs and AFs.