Percorrer por autor "Fuchs, Dietmar"
A mostrar 1 - 4 de 4
Resultados por página
Opções de ordenação
- Assessment of immunotoxicity parameters in individuals occupationally exposed to leadPublication . García-Lestón, Julia; Roma-Torres, Joana; Mayan, Olga; Schroecksnadel, Sebastian; Fuchs, Dietmar; Moreira, Ana; Pásaro, Eduardo; Méndez, Josefina; Teixeira, João Paulo; Laffon, BlancaAlthough adverse health effects produced by lead (Pb) have long been recognized, studies regarding the immunotoxic effects of occupational exposure report conflicting results. In a previous study, alterations in some immunological parameters were noted in 70 Pb-exposed workers. In view of these results, it was of interest to extend this study comprising a larger population and increasing the number of immunological endpoints assessed. Accordingly, in this study the immunotoxic effects of occupational exposure to Pb were assessed by analyzing (1) percentages of lymphocyte subsets (CD3⁺, CD4⁺, CD8⁺, CD19⁺, and CD56⁺/16⁺); (2) concentration of plasma cytokines, namely, interleukin (IL) 2, IL4, IL6, IL10, tumor necrosis factor (TNF) α, and interferon (IFN) γ; and (3) plasma concentrations of neopterin, tryptophan (Trp), and kynurenine (Kyn). In addition, the possible influence of genetic polymorphisms in the vitamin D receptor (VDR) and δ-aminolevulinic acid dehydratase (ALAD) genes on immunotoxicity parameters was studied. Exposed workers showed significant decreases in %CD3⁺, %CD4⁺/%CD8⁺ ratio, IL4, TNFα, IFNγ, and Kyn to Trp ratio (Kyn/Trp), and significant increases in %CD8⁺, IL10, and Trp levels. All these parameters, except Trp, were significantly correlated with exposure biomarkers. No significant influence of genetic polymorphisms was observed. Significant correlation between Kyn/Trp and neopterin concentrations suggests an involvement of indoleamine 2,3-dioxygenase in the Trp metabolic alterations, which may contribute to some of the immune alterations observed. Results obtained suggest that occupational exposure to PB may influence the immune system by impairing several mechanisms, which might ultimately produce deregulation of the immune response and diminish immunosurveillance in exposed individuals.
- Exploring Early Detection of Frailty Syndrome in Older Adults: Evaluation of Oxi-Immune Markers, Clinical Parameters and Modifiable Risk FactorsPublication . Teixeira-Gomes, Armanda; Laffon, Blanca; Valdiglesias, Vanessa; Gostner, Johanna M.; Felder, Thomas; Costa, Carla; Madureira, Joana; Fuchs, Dietmar; Teixeira, João Paulo; Costa, SolangeAgeing is accompanied with a decline in several physiological systems. Frailty is an age-related syndrome correlated to the loss of homeostasis and increased vulnerability to stressors, which is associated with increase in the risk of disability, comorbidity, hospitalisation, and death in older adults. The aim of this study was to understand the relationship between frailty syndrome, immune activation, and oxidative stress. Serum concentrations of vitamins A and E were also evaluated, as well as inflammatory biomarkers (CRP and IL-6) and oxidative DNA levels. A group of Portuguese older adults (≥65 years old) was engaged in this study and classified according to Fried's frailty phenotype. Significant increases in the inflammatory mediators (CRP and IL-6), neopterin levels, kynurenine to tryptophan ratio (Kyn/Trp), and phenylalanine to tyrosine ratio (Phe/Tyr), and significant decreases in Trp and Tyr concentrations were observed in the presence of frailty. IL-6, neopterin, and Kyn/Trp showed potential as predictable biomarkers of frailty syndrome. Several clinical parameters such as nutrition, dependency scales, and polypharmacy were related to frailty and, consequently, may influence the associations observed. Results obtained show a progressive immune activation and production of pro-inflammatory molecules in the presence of frailty, agreeing with the inflammageing model. Future research should include different dimensions of frailty, including psychological, social, biological, and environmental factors.
- Exploring the potential relation between immune biomarkers and frailty syndrome in older adults: preliminary results from the BioFrail studyPublication . teixeira-gomes, Armanda; Costa, Solange; lage, Bruna; Fuchs, Dietmar; Valdiglesias, Vanessa; Laffon, Blanca; Teixeira, João PauloObjectives: On this basis, the main objective of the present work was to evaluate the possible association between immunological: biomarkers and the frailty status in a group of community dwellers.
- NanoLINEN: Nanotoxicology Link Between India and European NationsPublication . Dhawan, Alok; Shanker, Rishi; Laffon, Blanca; Tajes, Juan Fernandez; Fuchs, Dietmar; van der Laan, Gert; van Broekhuizen, Pieter; Becker, Heidi; Moriske, Heinz-Jorn; Teixeira, João Paulo; Carriere, Marie; Herlin-Boime, Nathalie; Engin, Ayse Basak; Coskun, Erdem; Karahalil, BensuNanotoxicology link between India and European Nations (NanoLINEN) is a consortium of 7 European laboratories and Indian Institute of Toxicology Research (CSIR Laboratory) from India to strengthen the research ties in the area of Nanomaterial Toxicology. The goal of this project is to develop robust risk assessment methodologies that will be useful for the community manufacturing and using nano-products.