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- Anatomic region differences and age-related changes on Na+ and K+ levels in human brainPublication . Pinto, Edgar; Ramos, P.; Carvalhido, A.; Pinto, N.; Mendes, R.; Santos, A.; Almeida, A.Neurodegenerative diseases (ND) have been the subject of intensive research in last years in an attempt to understand the mechanisms underlying the neurodegeneration process. The etiology of these diseases is multifactorial, involving a complex interaction between the aging, genetic predisposition and environmental factors. In particular, the role of metals as risk factors for neurodegenerative disorders is currently being studied. As regards to this topic, the knowledge of metal distribution in the brain is of major importance. Evidence suggests that Alzheimer's disease (AD) is associated with impaired depressed Na+/K+ ATPase levels in AD brain that might lead to a cellular ion imbalance. Recent studies show that a pronounced levels in AD brain that might lead to a cellular ion imbalance. Recent studies show that a pronounced and the age of individuals.
- Placental levels of essential and non‑essential trace element in relation to neonatal weight in Northwestern Spain: application of generalized additive modelsPublication . Álvarez‑Silvares, Esther ; Fernández‑Cruz, Tania ; Bermudez‑González, Mónica ; Rubio‑Cid, Paula ; Almeida, Agostinho ; Pinto, Edgar; Seoane‑Pillado, Teresa ; Martínez‑Carballo, ElenaAdequate gestational progression depends to a great extent on placental development, which can modify maternal and neonatal outcomes. Any environmental toxicant, including metals, with the capacity to affect the placenta can alter the development of the pregnancy and its outcome. The objective of this study was to correlate the placenta levels of 14 essential and non-essential elements with neonatal weight. We examined relationships between placental concentrations of arsenic, cadmium, cobalt, copper, mercury, lithium, manganese, molybdenum, nickel, lead, rubidium, selenium, strontium, and zinc from 79 low obstetric risk pregnant women in Ourense (Northwestern Spain, 42°20′12.1″N 7°51.844′O) with neonatal weight. We tested associations between placental metal concentrations and neonatal weight by conducting multivariable linear regressions using generalized linear models (GLM) and generalized additive models (GAM). While placental Co (p = 0.03) and Sr (p = 0.048) concentrations were associated with higher neonatal weight, concentrations of Li (p = 0.027), Mo (p = 0.049), and Se (p = 0.02) in the placenta were associated with lower newborn weight. Our findings suggest that the concentration of some metals in the placenta may affect fetal growth.
- Metals transfer from tobacco to cigarette smoke: Evidences in smokers’ lung tissuePublication . Pinto, Edgar; Cruz, Mariana; Ramos, Patrícia; Santos, Agostinho; Almeida, AgostinhoTobacco use kills millions of people every year around the world. The current level of 11 metals in tobacco was determined and their transfer rate to cigarette smoke was calculated as the difference between the total metal content in cigarettes and the amount present in its ashes. The metals content was also determined in the lung tissue of smokers and non-smokers in order to evaluate the marks that smoking leaves in this tissue. Metals content in tobacco ranged from less than 1μg/g (Co, Cd, Pb, As and Tl) to several hundreds of μg/g (Al, Mn and Ba). The highest transfer rate from tobacco to cigarette smoke was found for Tl (85-92%) and Cd (81-90%), followed by Pb (46-60%) and As (33-44%). Significantly higher levels of As, Cd and Pb were found in the lung tissue of smokers compared to non-smokers, showing that smoking results in an increase of these metals in the lungs and that they contribute to the carcinogenic potential of cigarette smoke. This study presents important data on current metals content in tobacco and its transference to cigarette smoke and provides evidence of their accumulation in smokers' lung tissue.
- Uncovering the effects of copper feed supplementation on the selection of copper-tolerant and antibiotic-resistant Enterococcus in poultry production for sustainable environmental practicesPublication . Rebelo, Andreia; Duarte, Bárbara; Freitas, Ana R.; Almeida, Agostinho; Azevedo, Rui; Pinto, Edgar; Peixe, Luísa; Antunes, Patrícia; Novais, CarlaThe use of antibiotics in animal production is linked to the emergence and spread of antibiotic-resistant bacteria, a threat to animal, environmental and human health. Copper (Cu) is an essential element in poultry diets and an alternative to antibiotics, supplementing inorganic or organic trace mineral feeds (ITMF/OTMF). However, its contribution to select multidrug-resistant (MDR) and Cu tolerant Enterococcus, a bacteria with a human-animal-environment-food interface, remains uncertain. We evaluated whether feeding chickens with Cu-ITMF or Cu-OTMF contributes to the selection of Cu tolerant and MDR Enterococcus from rearing to slaughter. Animal faeces [2–3-days-old (n = 18); pre-slaughter (n = 16)] and their meat (n = 18), drinking-water (n = 14) and feed (n = 18) from seven intensive farms with ITMF and OTMF flocks (10.000–64.000 animals each; 2019–2020; Portugal) were sampled. Enterococcus were studied by cultural, molecular and whole-genome sequencing methods and Cu concentrations by ICP-MS. Enterococcus (n = 477; 60 % MDR) were identified in 80 % of the samples, with >50 % carrying isolates resistant to tetracycline, quinupristin-dalfopristin, erythromycin, streptomycin, ampicillin or ciprofloxacin. Enterococcus with Cu tolerance genes, especially tcrB ± cueO, were mainly found in faeces (85 %; E. faecium/E. lactis) of ITMF/OTMF flocks. Similar occurrence and load of tcrB ± cueO Enterococcus in the faeces was detected throughout the chickens' lifespan in the ITMF/OTMF flocks, decreasing in meat. Most of the polyclonal MDR Enterococcus population carrying tcrB ± cueO or only cueO (67 %) showed a wild-type phenotype (MICCuSO4 ≤ 12 mM) linked to absence of tcrYAZB or truncated variants, also detected in 85 % of Enterococcus public genomes from poultry. Finally, < 65 μg/g Cu was found in all faecal and meat samples. In conclusion, Cu present in ITMF/OTMF is not selecting Cu tolerant and MDR Enterococcus during chickens' lifespan. However, more studies are needed to assess the minimum concentration of Cu required for MDR bacterial selection and horizontal transfer of antibiotic resistance genes, which would support sustainable practices mitigating antibiotic resistance spread in animal production and the environment beyond.
- Elemental impurities in lipsticks: Results from a survey of the Portuguese and Brazilian marketsPublication . Pinto, Edgar; Paiva, Kainá; Carvalhido, Ana; Almeida, AgostinhoFor safety reasons, European regulations prohibit the use of a long list of metal(loid)s as ingredients of cosmetic products. However, their presence as impurities in finished products is virtually unavoidable, even under GMP conditions. This study aimed at determining the elemental profile of lipsticks available in the Portuguese and Brazilian markets. A total of 96 lipsticks were purchased in Brazil (n = 53; 9 brands) and Portugal (n = 43; 7 brands) and the content of 44 elements was determined. Results ranged from <1 μg/g to several tens of μg/g (e.g., Sn, Mn, Zn). Significant differences were found between Portuguese and Brazilian products for several elements, particularly for Pb. For the elements of major toxicological concern (Pb, Cd, As, Sb, Hg), mean values were always below the current limits set by the German competent authority. However, a significant percentage of exceedances were observed for Pb (24%) and Cd (21%). A safety assessment was carried out for the toxicologically relevant elements. Results showed that, except for Pb, the systemic exposure resulting from lipstick use represents less than 0.2% (ca. 3% for Pb) of the respective permitted daily exposure even in the worst-case scenario (i.e., ingestion of the total amount of product applied).