Alterações histopatológicas e indução de CYP1A em juvenis de Sparus aurata expostos a benzo(a)pireno e naftaleno

Dissertação mest., Aquacultura e Pescas, Universidade do Algarve, 2009O objectivo do presente estudo foi a determinação da resposta histopatológica e a indução de CYP1A no fígado, brânquias, rim e tracto gastrointestinal de juvenis de dourada, Sparus aurata, expostos a benzo(a)pireno (B[a]P) e naftaleno (N[a]P). Os juvenis de dourada foram expostos durante 15 dias a diferentes concentrações subletais de PAHs (B[a]P e N[a]P). As amostragens do tratamento controlo e dos tratamentos com os contaminantes foram efectuadas após 24 e 72 horas (curto período de exposição) e 5 e 15 dias (longo período de exposição). A resposta histopatológica foi analisada através das técnicas clássicas de coloração morfológica. A distribuição celular da proteína CYP1A foi determinada pelo método imunohistoquímico, usando como anticorpo primário o anticorpo monoclonal C10-7 e como anticorpo secundário o anticorpo anti-rato IgG biotinilado. Conjuntamente, a distribuição de carbohidratos e proteínas foi avaliada através de métodos histoquímicos clássicos. Alterações histopatológicas foram localizadas nos órgãos alvo dos exemplares expostos a ambos os contaminantes. Nos tratamentos com B[a]P e N[a]P, as lesões histopatológicas apresentaram dependência com a concentração e o tempo de exposição, indicando maior índice de lesão nos peixes amostrados no final do período experimental (15 dias). As lesões histopatológicas foram mais pronunciadas para N[a]P do que B[a]P no final do período de exposição. Contrariamente, os valores de CYP1A foram superiores para B[a]P no mesmo período experimental, corroborando o papel protector de CYP1A através do metabolismo de compostos tóxicos. O principal local de indução de CYP1A foi o endotélio vascular. Além disso, os resultados revelaram elevados níveis de indução de CYP1A em três órgãos alvo (fígado, brânquias e rins). Este estudo confirma a teoria do fígado ser o principal órgão metabólico nos peixes e, apresenta evidências de uma substâncial participação das brânquias e rins no metabolismo dos xenobióticos

SARS-CoV-2 introductions and early dynamics of the epidemic in Portugal

Genomic surveillance of SARS-CoV-2 in Portugal was rapidly implemented by the National Institute of Health in the early stages of the COVID-19 epidemic, in collaboration with more than 50 laboratories distributed nationwide. Methods By applying recent phylodynamic models that allow integration of individual-based travel history, we reconstructed and characterized the spatio-temporal dynamics of SARSCoV-2 introductions and early dissemination in Portugal. Results We detected at least 277 independent SARS-CoV-2 introductions, mostly from European countries (namely the United Kingdom, Spain, France, Italy, and Switzerland), which were consistent with the countries with the highest connectivity with Portugal. Although most introductions were estimated to have occurred during early March 2020, it is likely that SARS-CoV-2 was silently circulating in Portugal throughout February, before the first cases were confirmed. Conclusions Here we conclude that the earlier implementation of measures could have minimized the number of introductions and subsequent virus expansion in Portugal. This study lays the foundation for genomic epidemiology of SARS-CoV-2 in Portugal, and highlights the need for systematic and geographically-representative genomic surveillance.We gratefully acknowledge to Sara Hill and Nuno Faria (University of Oxford) and Joshua Quick and Nick Loman (University of Birmingham) for kindly providing us with the initial sets of Artic Network primers for NGS; Rafael Mamede (MRamirez team, IMM, Lisbon) for developing and sharing a bioinformatics script for sequence curation (https://github.com/rfm-targa/BioinfUtils); Philippe Lemey (KU Leuven) for providing guidance on the implementation of the phylodynamic models; Joshua L. Cherry (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health) for providing guidance with the subsampling strategies; and all authors, originating and submitting laboratories who have contributed genome data on GISAID (https://www.gisaid.org/) on which part of this research is based. The opinions expressed in this article are those of the authors and do not reflect the view of the National Institutes of Health, the Department of Health and Human Services, or the United States government. This study is co-funded by Fundação para a Ciência e Tecnologia and Agência de Investigação Clínica e Inovação Biomédica (234_596874175) on behalf of the Research 4 COVID-19 call. Some infrastructural resources used in this study come from the GenomePT project (POCI-01-0145-FEDER-022184), supported by COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation (POCI), Lisboa Portugal Regional Operational Programme (Lisboa2020), Algarve Portugal Regional Operational Programme (CRESC Algarve2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF), and by Fundação para a Ciência e a Tecnologia (FCT).info:eu-repo/semantics/publishedVersio

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved