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Lima, E.

Publications and source records attributed to Lima, E..

3 recordsLinked to original sources

Eco-Friendly Antifouling Solutions: Hazard Assessment of Synthetic Derivatives of Natural Compounds

The accumulation of microorganisms and macroorganisms on aquatic surfaces poses economic and ecological challenges, particularly in maritime transport. Traditional antifouling methods, such as biocidal coatings containing toxic compounds like tributyltin (TBT) and copper, are effective but harmful to the environment. This study investigates eco-friendly antifouling alternatives, focusing on nature-inspired compounds (NIAFs) GBA 26 (GBA) and DPC345DHC (DH345), derived from polyphenols and flavonoids, respectively. The ecotoxicity of these compounds was evaluated using standardized assays with various species, including embryos of Danio rerio (zebrafish) (OECD TG 236), the algae Raphidocelis subcapitata (OECD TG 201), and the bacteria Vibrio fischeri (ISO 11348-2), along with nuclear receptor transactivation assays in Mytilus galloprovincialis (Mediterranean mussel). Gallic acid derivative GBA and 24h-transformation products showed low toxicity in zebrafish embryos, while dihydrochalcone DH345 inflicted developmental toxicity in zebrafish at 1 mg/L and above. Comparatively, tralopyril, a commercial biocide, exhibited significant toxicity at lower concentrations. Transcriptomic analysis of zebrafish embryos treated with GBA revealed selective gene modulation related to stress response, ion transport, and protein synthesis. Both, GBA and DH345, were shown to inhibit algae growth at 0.1 mg/L. Vibrio fischeri assay showed no toxic effects for any of the tested compounds. Nuclear receptor transactivation assays conducted with GBA revealed no activation of PPAR or PXR receptors. These findings suggest GBA and DH345 as potential eco-friendly antifouling agents with lower environmental risks than established antifoulants such as tralopyril. However, further research is needed to evaluate their potential long-term ecological impacts, particularly chronic toxicity across various organisms. This study advances the pursuit of sustainable antifouling solutions that prioritize environmental protection.

ecology↗

A spontaneous mutation in ADIPOR1 causes retinal degeneration in mice

Adiponectin receptor 1 (ADIPOR1) is a transmembrane protein necessary for normal anatomy and physiology in the retina. In a recent study of complement factor H knockout mice (Cfh-/-), our lab discovered a flecked retina phenotype and retinal thinning by fundus imaging and optical coherence tomography (OCT), respectively. The phenotype was observed in a subset (50%) of Cfh-/- mice. The thinning observed in vivo is due to an early degeneration of rod photoreceptors. This phenotype has not been reported in published studies of Cfh-/- mice. AdipoR1 knockout mice (AdipoR1-/-) and mice deficient in Membrane Frizzled Related Protein (MFRP) exhibit this phenotype, suggesting an involvement in the emergence of the retinal degeneration observed in a subset of Cfh-/- mice. Cfh and AdipoR1 are located in close proximity on mouse Chromosome 1 (Chr1) and a complementation cross between Cfh and AdipoR1 mice with retinal degeneration produced 100% progeny with retinal degeneration. Sequencing of the Cfh-/- mice revealed a c.841 C > T mutation in AdipoR1. Furthermore, one Cfh wildtype (of Cfh+/+) and 2 heterozygous (of Cfh+/-) mice exhibited retinal degeneration and were homozygous for the point mutation. The c.841 C > T mutation results in a proline to serine conversion at position 281 (P281S) in ADIPOR1. This residue is critical for ADIPOR1 open and closed conformations in the membrane. In silico modeling of candidate ADIPOR1 ligands, 11-cis-retinaldehyde and docosahexaenoic acid (DHA), that are deficient in AdipoR1-/-, suggests that ADIPOR1 is involved in trafficking retinoids and fatty acids and their combined deficiency in the ADIPOR1 mutant retinas might explain the retinal degeneration phenotype.

neuroscience↗

Zika virus infection induces synthesis of Digoxin in glioblastoma cells

Recently, microcephaly cases have increased in Americas and have been matter of concern due to Zika virus (ZIKV) recent outbreak. Previous studies have shown that ZIKV-infected progenitor neuronal cells present morphological abnormalities and increased rates of cell death, which may be indicators of microcephaly causes. As recent studies indicate Zika virus tropism for brain cells, how would a glioblastoma (GBM) lineage behave under ZIKV infection, considering GBM the most common and malignant brain tumor in adults, presenting extreme chemoresistance and high morbidity and mortality rates? The current trend of using genetically engineered oncolytic pathogens as a safe way to eliminate tumors is under development, with trials already in course. Therefore, the present study evaluated the possible oncolytic effects and metabolomic alterations of Zika virus infection at human malignant M059J glioblastoma cells. Microscopic evaluation was performed using optical microscopy, which showed cytopathic effects induced by ZIKV at GBM cells. For the metabolomics study, both control and infected cell cultures were submitted to MALDI-MSI analysis. Mass spectrometry data were submitted to PLS-DA statistical analysis, and distinct biomarkers were elected for each infected groups. This study brings light to unexpectedly induced metabolic changes, as endogenous Digoxin as important biomarker for ZIKV-GBM group, associated with cytopathic effects induced by viral infection. These results evidences that genetically engineered ZIKV might be a potential new strategy for neural cancer management through the induction of endogenous digoxin synthesis in glioblastoma cells.

neuroscience↗