Browsing by Author "Côrte-Real, R"
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- Chlamydia Trachomatis: When the Virulence-Associated Genome Backbone Imports a Prevalence-Associated Major Antigen SignaturePublication . Borges, V; Cordeiro, D; Salas, AI; Lodhia, Z; Correia, C; Isidro, J; Fernandes, C; Rodrigues, AM; Azevedo, J; Alves, J; Roxo, J; Rocha, M; Côrte-Real, R; Vieira, L; Borrego, MJ; Gomes, JPChlamydia trachomatis is the most prevalent sexually transmitted bacterium worldwide and the causative agent of trachoma. Its strains are classified according to their ompA genotypes, which are strongly linked to differential tissue tropism and disease outcomes [ocular disease, urogenital disease and lymphogranuloma venereum (LGV)]. While the genome-based species phylogenetic tree presents four main clades correlating with tropism/prevalence, namely ocular, LGV, urogenital T1 (more prevalent genotypes) and urogenital T2 (less prevalent genotypes), inter-clade exchange of ompA is considered a rare phenomenon probably mediating marked tropism alterations. An LGV epidemic, associated with the clonal expansion of the L2b genotype, has emerged in the last few decades, raising concerns particularly due to its atypical clinical presentation (ulcerative proctitis) and circulation among men who have sex with men (MSM). Here, we report an LGV outbreak, mostly affecting human immunodeficiency virus-positive MSM engaging in high-risk sexual practices, caused by an L2b strain with a rather unique non-LGV ompA signature that precluded the laboratory notification of this outbreak as LGV. C. trachomatis whole-genome capture and sequencing directly from clinical samples was applied to deeply characterize the genomic backbone of this novel LGV outbreak-causing clone. It revealed a chimeric genome structure due to the genetic transfer of ompA and four neighbouring genes from a serovar D/Da strain, likely possessing the genomic backbone associated with the more prevalent urogenital genotypes (T1 clade), to an LGV (L2b) strain. The hybrid L2b/D-Da strain presents the adhesin and immunodominant antigen MOMP (major outer membrane protein) (encoded by ompA) with an epitope repertoire typical of non-invasive genital strains, while keeping the genome-dispersed virulence fingerprint of a classical LGV strain. As previously reported for inter-clade ompA exchange among non-LGV clades, this novel C. trachomatis genomic mosaic involving a contemporary epidemiologically and clinically relevant LGV strain may have implications on its transmission, tissue tropism and pathogenic capabilities. The emergence of variants with epidemic and pathogenic potential highlights the need for more focused surveillance strategies to capture C. trachomatis evolution in action.
- Cross-Protection to New Drifted Influenza A(H3) Viruses and Prevalence of Protective Antibodies to Seasonal Influenza, During 2014 in PortugalPublication . Guiomar, R; Pereira da Silva, S; Conde, P; Cristóvão, P; Maia, AC; Pechirra, P; Rodrigues, AP; Nunes, B; Milho, L; Coelho, AP; Fernandes, A; Caseiro, P; Rodrigues, F; Correia, L; Pereira-Vaz, J; Almeida, S; Branquinho, P; Côrte-Real, R; Viseu, R; Peres, MJ; Sanches, R; Dantas, F; Freitas, L; Andrade, G; Maurílio, M; Caldeira, F; Cabral Veloso, R; Mota-Vieira, L; Soares, M; Couto, AR; Bruges-Armas, J; Mouro Pinto, R; Sobrinho Simões, J; Costa, MR; Guimarães, JT; Martins, L; Cunha, MINTRODUCTION: Immune profile for influenza viruses is highly changeable over time. Serological studies can assess the prevalence of influenza, estimate the risk of infection, highlight asymptomatic infection rate and can also provide data on vaccine coverage. The aims of the study were to evaluate pre-existing cross-protection against influenza A(H3) drift viruses and to assess influenza immunity in the Portuguese population. MATERIALS AND METHODS: We developed a cross-sectional study based on a convenience sample of 626 sera collected during June 2014, covering all age groups, both gender and all administrative health regions of Portugal. Sera antibody titers for seasonal and new A(H3) drift influenza virus were evaluated by hemagglutination inhibition assay (HI). Seroprevalence to each seasonal influenza vaccine strain virus and to the new A(H3) drift circulating strain was estimated by age group, gender and region and compared with seasonal influenza-like illness (ILI) incidence rates before and after the study period. RESULTS: Our findings suggest that seroprevalences of influenza A(H3) (39.9%; 95% CI: 36.2-43.8) and A(H1)pdm09 (29.7%; 95% CI: 26.3-33.4) antibodies were higher than for influenza B, in line with high ILI incidence rates for A(H3) followed by A(H1)pdm09, during 2013/2014 season. Low pre-existing cross-protection against new A(H3) drift viruses were observed in A(H3) seropositive individuals (46%). Both against influenza A(H1)pdm09 and A(H3) seroprotection was highest in younger than 14-years old. Protective antibodies against influenza B were highest in those older than 65years old, especially for B/Yamagata lineage, 33.3% (95% CI: 25.7-41.9). Women showed a high seroprevalence to influenza, although without statistical significance, when compared to men. A significant decreasing trend in seroprotection from north to south regions of Portugal mainland was observed. CONCLUSIONS: Our results emphasize that low seroprotection increases the risk of influenza infection in the following winter season. Seroepidemiological studies can inform policy makers on the need for vaccination and additional preventive measures.
- HIV-1-Transmitted Drug Resistance and Transmission Clusters in Newly Diagnosed Patients in Portugal Between 2014 and 2019Publication . Pingarilho, M; Pimentel, V; Miranda, M; Silva, AR; Diniz, A; Ascenção, B; Piñeiro, C; Koch, C; Rodrigues, C; Caldas, C; Morais, C; Faria, D; Gomes da Silva, E; Teófilo, E; Monteiro, F; Roxo, F; Maltez, F; Rodrigues, F; Gaião, G; Ramos, H; Costa, I; Germano, I; Simões, J; Oliveira, J; Ferreira, J; Poças, J; Saraiva da Cunha, J; Soares, J; Henriques, J; Mansinho, K; Pedro, L; Aleixo, MJ; Gonçalves, MaJ; Manata, MJ; Mouro, M; Serrado, M; Caixeiro, M; Marques, N; Costa, O; Pacheco, P; Proença, P; Rodrigues, P; Pinho, R; Tavares, R; Correia de Abreu, R; Côrte-Real, R; Serrão, R; Sarmento e Castro, R; Nunes, S; Faria, T; Baptista, T; Martins, MR; Gomes, P; Mendão, L; Simões, D; Abecasis, AObjective: To describe and analyze transmitted drug resistance (TDR) between 2014 and 2019 in newly infected patients with HIV-1 in Portugal and to characterize its transmission networks. Methods: Clinical, socioepidemiological, and risk behavior data were collected from 820 newly diagnosed patients in Portugal between September 2014 and December 2019. The sequences obtained from drug resistance testing were used for subtyping, TDR determination, and transmission cluster (TC) analyses. Results: In Portugal, the overall prevalence of TDR between 2014 and 2019 was 11.0%. TDR presented a decreasing trend from 16.7% in 2014 to 9.2% in 2016 (p for-trend = 0.114). Multivariate analysis indicated that TDR was significantly associated with transmission route (MSM presented a lower probability of presenting TDR when compared to heterosexual contact) and with subtype (subtype C presented significantly more TDR when compared to subtype B). TC analysis corroborated that the heterosexual risk group presented a higher proportion of TDR in TCs when compared to MSMs. Among subtype A1, TDR reached 16.6% in heterosexuals, followed by 14.2% in patients infected with subtype B and 9.4% in patients infected with subtype G. Conclusion: Our molecular epidemiology approach indicates that the HIV-1 epidemic in Portugal is changing among risk group populations, with heterosexuals showing increasing levels of HIV-1 transmission and TDR. Prevention measures for this subpopulation should be reinforced.
- Infecção pelo Vírus da Hepatite B em Doentes Sujeitos a Terapêutica Imunossupressora ou Quimioterapia Citotóxica. A Propósito de um Caso ClínicoPublication . Redondo, I; Sousa, MI; Ramos, G; Fernandes, AT; Côrte-Real, R; Botelho, A; Neves, MMA reactivação do vírus da hepatite B em doentes com neoplasias hematológicas é uma complicação frequente da quimioterapia ou da terapêutica imunomoduladora. Os autores descrevem o caso dum doente com linfoma não-Hodgkin e história de infecção passada pelo VHB que desenvolveu hepatite fulminante após quimioterapia. Os mecanismos de reactivação do VHB são discutidos e as recomendações sobre profilaxia são apresentadas.
- Long-Term and Concentration-Dependent Beneficial Effect of Efavirenz on HDL-Cholesterol in HIV-Infected PatientsPublication . Pereira, SA; Branco, T; Côrte-Real, R; Germano, I; Lampreia, F; Caixas, U; Monteiro, EAIMS: To investigate the long-term effects of efavirenz on cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein (LDL-C) and triglycerides (TG). METHODS: Thirty-four HIV-infected patients who commenced efavirenz therapy were monitored for 36 months. RESULTS: In patients with baseline HDL-C<40 mg.dL-1 an increase in HDL-C from 31+/-1 mg.dL-1 to 44+/-2 mg.dL-1 (95% confidence interval 5.9, 21.9, P<0.01) was observed and remained throughout the follow-up period. Median efavirenz plasma concentration was 1.98 mg.L-1 and a direct correlation between percentage of HDL-C variation or TC/HDL-C ratio and efavirenz plasma concentrations was found. CONCLUSIONS: There is evidence of a long-term and concentration-dependent beneficial effect of efavirenz on HDL-C in HIV-infected patients.