Percorrer por autor "Medeiros-Fonseca, Beatriz"
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- Characterization of the Human Papillomavirus 16 Oncogenes in K14HPV16 Mice: Sublineage A1 Drives Multi-Organ CarcinogenesisPublication . Cochicho, Daniela; Nunes, Alexandra; Gomes, João Paulo; Martins, Luís; Cunha, Mário; Medeiros-Fonseca, Beatriz; Oliveira, Paula; Bastos, Margarida M.S.M.; Medeiros, Rui; Mendonça, Joana; Vieira, Luis; Gil da Costa, Rui M.; Felix, AnaThe study of ()-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.
- Do (xeno)estrogens pose a risk to earthworms? Soy isoflavones and estradiol impact gonad structure and induce oxidative stress in Eisenia fetidaPublication . Azevedo, Tiago; Silva-Reis, Rita; Medeiros-Fonseca, Beatriz; Gonçalves, Mariana; Mendes, Gabriel; Roboredo, Marta; Rocha, Maria J.; Peixoto, Francisco; Pinto, Maria de Lurdes; Matos, Manuela; Sousa, João R.; Oliveira, Paula A.; Coimbra, Ana M.Understanding the impact of endocrine disruptor compounds (EDCs) across a wide range of species is crucial, given their ubiquitous presence. Although invertebrate species lack sex steroid hormone pathways, they exhibit sensitivity to EDCs, which could affect population dynamics. This study assessed reproductive endpoints and oxidative stress parameters in Eisenia fetida following exposure to estradiol and soy isoflavones, resembling the concentrations found in livestock manure. The experiment used artificial soil, as recommended by OECD guidelines (7:2:1 sand, kaolin and peat). Adult specimens were randomly divided into seven groups (n = 11/replicate): one control, three estradiol (156.1, 283.4 and 633.8 μg/kg of dry soil) and three soy isoflavones (113.0, 215.3 and 405.0 mg/kg of dry soil) concentrations. After eight weeks, samples were collected for cytological, histological and biochemical analysis. Offspring development was assessed after 12 additional weeks. Higher estradiol and isoflavone concentrations led to lower germ cell number and increased abnormalities, especially in the seminal vesicles and ovaries. Catalase and peroxidase activities were significantly increased in all treated groups. The exposure did not significantly affect the number of E. fetida offspring. These findings highlight E. fetida’s sensitivity to EDCs at a biochemical and tissue level, suggesting its use as a bioindicator for assessing EDC contamination in soils.