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- Circulating cell-free DNA methylation mirrors alterations in cerebral patterns in epilepsyPublication . Martins-Ferreira, Ricardo; Leal, Bárbara; Chaves, João; Ciudad, Laura; Samões, Raquel; Martins da Silva, António; Pinho Costa, Paulo; Ballestar, EstebanBackground: DNA methylation profiling of circulating cell-free DNA (cfDNA) has rapidly become a promising strategy for biomarker identification and development. The cell-type-specific nature of DNA methylation patterns and the direct relationship between cfDNA and apoptosis can potentially be used non-invasively to predict local alterations. In addition, direct detection of altered DNA methylation patterns performs well as a biomarker. In a previous study, we demonstrated marked DNA methylation alterations in brain tissue from patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS). Results: We performed DNA methylation profiling in cfDNA isolated from the serum of MTLE patients and healthy controls using BeadChip arrays followed by systematic bioinformatic analysis including deconvolution analysis and integration with DNase accessibility data sets. Differential cfDNA methylation analysis showed an overrepresentation of gene ontology terms and transcription factors related to central nervous system function and regulation. Deconvolution analysis of the DNA methylation data sets ruled out the possibility that the observed differences were due to changes in the proportional contribution of cortical neurons in cfDNA. Moreover, we found no overrepresentation of neuron- or glia-specific patterns in the described cfDNA methylation patterns. However, the MTLE-HS cfDNA methylation patterns featured a significant overrepresentation of the epileptic DNA methylation alterations previously observed in the hippocampus. Conclusions: Our results support the use of cfDNA methylation profiling as a rational approach to seeking non-invasive and reproducible epilepsy biomarkers.
- Farming a wild seaweed and changes to its composition, bioactivity, and bioaccessibility: The Saccorhiza polyschides case studyPublication . Cardoso, C.; Almeida, J.; Coelho, I.; Delgado, I.; Gomes, R.; Quintã, R.; Bandarra, N.M.; Afonso, C.The nutritional value, elemental and fatty acid composition as well as key biological activities were determined in a large brown seaweed species (Saccorhiza polyschides, abundant in European shores), taking into account the effects of wild vs farmed and land-based vs open sea Integrated Multi-Trophic Aquaculture (IMTA) system dichotomies. The results showed that S. polyschides has significant amounts of relevant nutrients, some biological activity (anti-inflammatory), high contents of the essential elements Se (1.07–1.79 mg/kg dw) and I (367–522 mg/kg dw), and a high bioaccessibility of I. However, As levels should be monitored, given their high bioaccessibility (∼60–70% range), and I levels may translate into excessive I intake if too much seaweed is consumed (if daily consumption of dried S. polyschides exceeds 3 g dw). Regarding the wild-farmed dichotomy, wild S. polyschides had a moderately higher nutritional value, including a better ω3/ω6 ratio, but a lower Se content than farmed S. polyschides, 0.80 ± 0.01 vs 0.58–0.69 and 1.07 ± 0.05 vs 1.16–1.79 mg/kg dw, respectively. Furthermore, bioaccessibility of elements was not much affected by cultivation. Concerning land-based vs open sea IMTA, in comparison to S. polyschides in earthen ponds, lower Hg and Pb contamination, but higher Cd levels were determined in the seaweed cultivated in open sea. S. polyschides farming per se did not have a large deleterious impact on the characteristics of this edible seaweed and may ensure the production of large amounts of algal biomass for feed, food, and nutraceutical applications.