Browsing by Author "Nogueira, P.J."
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- Adaptive evolution of the Chlamydia trachomatis dominant antigen reveals distinct evolutionary scenarios for B- and T-cell epitopes: worldwide surveyPublication . Nunes, A.; Nogueira, P.J.; Borrego, M.J.; Gomes, João PauloBackground: Chlamydia trachomatis is one of the most disseminated human pathogens, for which no vaccine is available yet. Understanding the impact of the host pressure on pathogen antigens is crucial, but so far it was only assessed for highly-restricted geographic areas. We aimed to evaluate the evolutionary picture of the chlamydial key antigen (MOMP), which is one of the leading multi-subunit vaccine candidates, in a worldwide basis. Methodology/Principal Findings: Using genetics, molecular evolution methods and mathematical modelling, we analyzed all MOMP sequences reported worldwide, composed by 5026 strains from 33 geographic regions of five continents. Overall, 35.9% of variants were detected. The evolutionary pattern of MOMP amino acid gains/losses was found to differ from the remaining chromosome, reflecting the demanding constraints of this porin, adhesin and dominant antigen. Amino acid changes were 4.3-fold more frequent in host-interacting domains (P,10212), specifically within B-cell epitopes (P,1025), where 25% of them are at fixation (P,1025). According to the typical pathogen-host arms race, this rampant B-cell antigenic variation likely represents neutralization escape mutants, as some mutations were previously shown to abrogate neutralization of chlamydial infectivity in vitro. In contrast, T-cell clusters of diverse HLA specificities are under purifying selection, suggesting a strategy that may lead to immune subversion. Moreover, several silent mutations are at fixation, generating preferential codons that may influence expression, and may also reflect recombination-derived ‘hitchhikingeffect’ from favourable nonsilent changes. Interestingly, the most prevalent C. trachomatis genotypes, E and F, showed a mutation rate 22.3-fold lower than that of the remainder (P,10220), suggesting more fitted antigenic profiles. Conclusions/Significance: Globally, the adaptive evolution of the C. trachomatis dominant antigen is likely driven by its complex pathogenesis-related function and reflects distinct evolutionary antigenic scenarios that may benefit the pathogen, and thus should be taking into account in the development of a MOMP-based vaccine.
- A large community outbreak of Legionnaires’ disease in Vila Franca de Xira, Portugal, October to November 2014Publication . Shivaji, T.; Sousa Pinto, C.; San-Bento, A.; Oliveira Serra, L.A.; Valente, J.; Machado, J.; Marques, T.; Carvalho, L.; Nogueira, P.J.; Nunes, Baltazar; Vasconcelos, P.An outbreak of Legionnaires’ disease with 334 confirmed cases was identified on 7 November 2014 in Vila Franca de Xira, Portugal and declared controlled by 21 November. Epidemiological, environmental and microbiological analysis identified industrial wet cooling systems to be the probable source of infection. Preliminary results from sequence-based typing of clinical specimens and environmental isolates confirmed this link. A series of meteorological phenomena are likely to have contributed to the scale of this outbreak.
- Relatório do Grupo de Trabalho de Estatísticas da SaúdePublication . Nogueira, P.J.; Martins, J.N.; Lemos, B.; Góis, E.; Elavai, A.; Rodrigues, G.; Dias, Carlos Matias; Couceiro, L.; Alves, I.; Lourenço, A.; Borges, CláudiaO Grupo de Trabalho de Estatísticas de Saúde - GTES foi criado no âmbito do Conselho Superior de Estatística (Secção Permanente de Estatísticas Sociais), com o objetivo de identificar e redefinir o conteúdo do sistema de informação das estatísticas oficiais de saúde nos domínios “estado de saúde e seus determinantes”, “cuidados de saúde”, e “causas de morte”. Para atingir esse objetivo o Grupo, em primeiro lugar, identificou as ineficiências do atual sistema e, posteriormente, diagnosticou as necessidades nacionais e internacionais de informação, de modo a apresentar propostas fundamentadas para a sua reestruturação e racionalização. Neste quadro, a clarificação dos procedimentos de recolha a adotar, com destaque para a explicitação dos atos administrativos existentes, assumiram, desde o início, especial referência no mandato proposto para o GTES.
- The new automated daily mortality surveillance system in PortugalPublication . Nogueira, P.J.; Machado, A.; Rodrigues, E.; Nunes, Baltazar; Sousa, L.; Jacinto, M.; Ferreira, A.; Falcão, J.M.; Ferrinho, P.The experience reported in an earlier Eurosurveillance issue on a fast method to evaluate the impact of the 2003 heatwave on mortality in Portugal, generated a daily mortality surveillance system (VDM) that has been operating ever since jointly with the Portuguese Heat Health Watch Warning System. This work describes the VDM system and how it evolved to become an automated system operating year-round, and shows briefly its potential using mortality data from January 2006 to June 2009 collected by the system itself. The new system has important advantages such as: rapid information acquisition, completeness (the entire population is included), lightness (very little information is exchanged, date of death, age, sex, place of death registration). It allows rapid detection of impacts (within five days) and allows a quick preliminary quantification of impacts that usually took several years to be done. These characteristics make this system a powerful tool for public health action. The VDM system also represents an example of inter-institutional cooperation, bringing together organisations from two different ministries, Health and Justice, aiming at improving knowledge about the mortality in the population.