Percorrer por autor "Maltez, Fernando"
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- Clonal expansion across the seas as seen through CPLP-TB database: a joint effort in cataloguing Mycobacterium tuberculosis genetic diversity in Portuguese-speaking countriesPublication . Perdigão, João; Silva, Carla; Diniz, Jaciara; Pereira, Catarina; Machado, Diana; Ramos, Jorge; Silva, Hugo; Abilleira, Fernanda; Brum, Clarice; Reis, Ana J.; Macedo, Maíra; Scaini, João L.; Silva, Ana B.; Esteves, Leonardo; Macedo, Rita; Maltez, Fernando; Clemente, Sofia; Coelho, Elizabeth; Viegas, Sofia; Rabna, Paulo; Rodrigues, Amabélia; Taveira, Nuno; Jordao, Luísa; Kritski, Afrânio; Silva, José Lapa e; Mokrousov, Igor; Couvin, David; Rastogi, Nalin; Couto, Isabel; Pain, Arnab; McNerney, Ruth; Clark, Taane G.; von Groll, Andrea; Dalla-Costa, Elis R.; Rossetti, Maria Lúcia; Silva, Pedro E.A. da; Viveiros, Miguel; Portugal, IsabelTuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. To address this, we have assembled and analyzed the largest CPLP M.tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. The data herein presented reinforces Latin American and Mediterranean (LAM) strains as the hallmark of M. tuberculosis populational structure in the CPLP coupled with country-specific differential prevalence of minor clades. Moreover, using high-resolution typing by 24-loci MIRU-VNTR, six cross-border genetic clusters were detected, thus supporting recent clonal expansion across the Lusophone space. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. As a public health tool, it is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting the risk assessment of strain-specific trends.
- Emergence of multidrug-resistant Mycobacterium tuberculosis of the Beijing lineage in Portugal and Guinea-Bissau: a snapshot of moving clones by whole-genome sequencingPublication . Perdigão, João; Silva, Carla; Maltez, Fernando; Machado, Diana; Miranda, Anabela; Couto, Isabel; Rabna, Paulo; Florez de Sessions, Paola; Phelan, Jody; Pain, Arnab; McNerney, Ruth; Hibberd, Martin L.; Mokrousov, Igor; Clark, Taane G.; Viveiros, Miguel; Portugal, IsabelThe Beijing genotype comprises a highly disseminated strain type that is frequently associated with multidrug resistant (MDR) tuberculosis (TB) and increased transmissibility but, countries such as Portugal and Guinea-Bissau fall outside the regions phylogeographically associated with this specific genotype. Nevertheless, recent data shows that this genotype might be gradually emerging in these two countries as an underlying cause of primary MDR-TB. Here, we describe the emergence of Mycobacterium tuberculosis Beijing strains associated with MDR-TB in Portugal and Guinea-Bissau demonstrating the presence of the well described superclusters 100-32 and 94-32 in Portugal and Guinea-Bissau, respectively. Genome-wide analysis and comparison with a global genomic dataset of M. tuberculosis Beijing strains, revealed the presence of two genomic clusters encompassing isolates from Portugal and Guinea-Bissau, GC1 (n = 121) and GC2 (n = 39), both of which bore SNP signatures compatible with the 100-32/B0/W148 and 94-32/Central Asia Outbreak clades, respectively. Moreover, GC2 encompasses a cross-border cluster between Portugal, Guinea-Bissau and Brazil thus supporting migration-associated introduction of MDR-TB and subsequent clonal expansion at the community-level. The comparison with global Beijing datasets demonstrates the global reach of the disease and its complex dissemination across multiple countries while in parallel there are clear microevolutionary trajectories towards extensively drug resistant TB.
- Frequência de Mutações de Resistência aos ARVs em novos casos de infeção por VIH-1, diagnosticados em Portugal no ano 2018Publication . Aldir, Isabel; Cortes Martins, Helena; Caetano, Constantino; Sarmento, António; Serrão, Rosário; Saraiva da Cunha, José; Oliveira, Joaquim; Maltez, Fernando; Manata, Maria José; Mansinho, Kamal; Ayres Pereira, Álvaro; Zagalo Melo, Alexandra; Afonso, Cláudia; Marques, Nuno; Aleixo, Maria João; Faria, Domitília; Proença., Ana PaulaIntrodução: A avaliação da presença de mutações que confiram resistência aos fármacos usados no tratamento da infeção por VIH-1, faz parte da avaliação laboratorial efetuada no quadro de um diagnóstico de novo, e a monitorização da sua prevalência é preconizada internacionalmente. Objetivos: Avaliar a frequência de mutações de resistência (MR) entre doentes com diagnóstico estabelecido em 2018 e identificar determinantes para a sua ocorrência.
- Genomic diversity of drug-resistant mycobacterium tuberculosis isolates in Lisbon Portugal: towards tuberculosis genomic epidemiologyPublication . Perdigão, João; Silva, Hugo; Machado, Diana; Macedo, Rita; Maltez, Fernando; Silva, Carla; Jordão, Luísa; Couto, Isabel; Mallard, Kim; Coll, Francesc; Hill-Cawthorne, Grant A; Pain, Arnab; Clark, Taane G; Viveiros, Miguel; Portugal, IsabelMultidrug- (MDR) and extensively drug resistant (XDR) tuberculosis (TB) present a challenge to disease control and elimination goals. Lisbon, Portugal, has a high TB incidence rate and, unusual and successful XDR-TB strains that are found in circulation for almost two decades. In the present study, 56 Mycobacterium tuberculosis isolates, mostly recovered in Lisbon, were genotyped by 24-loci Mycobacterial Interspersed Repetive Unit – Variable Number of Tandem Repeats (MIRU-VNTR) and the genomes sequenced using a next generation sequencing platform – Illumina HiSeq 2000. The genotyping data revealed three major clusters associated with MDR-TB (Lisboa3-A, Lisboa3-B and Q1), two of which associated with XDR-TB (Lisboa3-B and Q1). Whilst the genomic data contributed to elucidate the phylogenetic positioning of circulating MDR-TB strains, showing a high predominance of a single SNP cluster group 5. Furthermore, a genome-wide phylogeny analysis from these strains, together with 19 publicly available genomes of Mycobacterium tuberculosis clinical isolates, revealed two major clades responsible for M/XDR-TB in the region: Lisboa3 and Q1. On the overall, 9419 different SNPs were identified, ranging between 488 – 1465 per isolate (mean: 928 SNPs/isolate). The data presented by this study contributes to the expanding knowledge of Mycobacterium tuberculosis genomic diversity yielding insights on microevolution and identification of novel compensatory mutations associated with rifampicin resistance in rpoB and rpoC. The screening for other structural variations revealed putative clade-defining variants. One deletion in PPE41, found among Lisboa3 isolates, is proposed to contribute to immune evasion and as a selective advantage. Insertion sequence (IS) mapping has also demonstrated the role of IS6110 as a major driver in mycobacterial evolution by affecting gene integrity and regulation. A total of 251 candidate insertion sites were detected, of which 105 were intergenic and 64 were predicted to have a putative upregulatory effect. Additionally, the analysis of non-synonymous/synonymous ratios revealed heterogeneities across the chromosome, genotype and Clusters of Orthologous Groups, highlighting possible and different evolution strategies. Globally, our data supports the notion of a growing genomic diversity facing both setting and host adaptation.
- The impact of orthopoxvirus vaccination and Mpox infection on cross-protective immunity: a multicohort observational studyPublication . Crandell, Jameson; Pischel, Lauren; Fang, Zhenhao; Conde, Luciana; Zhong, Yi; Lawres, Lauren; Meira de Asis, Gustavo; Maciel, Gabriela; Zaleski, Agnieszka; Lira, Guilherme S.; Higa, Luiza M.; Breban, Mallery I.; Vogels, Chantal B.F.; Caria, João; Pinto, Ana Raquel; Almeida, Vasco; Maltez, Fernando; Cordeiro, Rita; Póvoas, Diana; Grubaugh, Nathan D.; Aoun-Barakat, Lydia; Grifoni, Alba; Sette, Alessandro; Castineiras, Terezinha M.; Chen, Sidi; Yildirim, Inci; Vale, Andre M.; Omer, Saad B.Background: Cross-reactive immune memory responses to orthopoxviruses in humans remain poorly characterised despite their relevance for vaccine design and outbreak control. We aimed to assess the magnitude, specificity, and durability of cross-reactive immune responses elicited by smallpox vaccines and mpox virus infection. Methods: We did a multicohort observational study involving participants from the USA, Brazil, and Portugal across four groups: Dryvax (first-generation smallpox vaccine) recipients vaccinated 40-80 years ago, JYNNEOS (third-generation smallpox vaccine) recipients vaccinated within the past year, a cohort receiving both vaccines, and patients infected with clade IIb mpox. Samples were analysed for systemic and mucosal humoral responses, neutralising antibody titres, viral antigen structural analysis, and T-cell cross-reactivity to vaccina virus, cowpox virus, and mpox virus. Statistical analyses included correlation assessments and comparisons across cohorts to determine the magnitude, longevity, and breadth of immune responses. Findings: Between July 7, 2022, and Aug 3, 2023, 262 participants were recruited, resulting in analysis of 378 samples. Both first-generation and third-generation smallpox vaccines elicited vaccinia virus-reactive and mpox virus-reactive antibodies, with the strongest responses targeting the less conserved extracellular virion antigens B5 and A33. Despite high concentrations of anti-mpox virus antibodies in the plasma, cross-neutralisation activity correlated with viral antigenic distance. Higher neutralisation was observed for cowpox virus than for mpox virus, which has lower antigenic conservation with vaccina virus. Complement-mediated neutralisation enhanced mpox virus neutralisation, overcoming the limitations of antigenic distance. Dryvax recipients sustained vaccina virus neutralisation titres for over 80 years, whereas cross-reactive responses did not show this durability. JYNNEOS-induced responses waned within a year. T-cell cross-reactivity was long-lasting, detected up to 70 years after vaccination. Booster vaccinations augmented the magnitude, breadth, and longevity of cross-neutralising responses. Interpretation: Our findings highlight the potential combined role of antibody effector functions and T-cell memory in cross-protection against orthopoxviruses. Complement-mediated neutralisation enhances cross-protection, overcoming antigenic distance. These Fc-mediated functions, along with T-cell responses, contribute to effective and long-lasting immunity conferred by smallpox vaccines against other orthopoxviruses.
- Insights on the Mycobacterium tuberculosis population structure associated with migrants from Portuguese-speaking countries over a three-year period in greater Lisbon, Portugal: Implications at the public health levelPublication . Pereira, Catarina; Gomes, Pedro; Taveira, Ricardo; Silva, Carla; Maltez, Fernando; Macedo, Rita; Costa, Catarina; Couvin, David; Rastogi, Nalin; Viveiros, Miguel; Perdigão, João; Portugal, IsabelTuberculosis among foreign-born patients is a key indicator of country-level epidemiological profiles and, of an increasing concern in Europe given the more intensified migratory waves of refugees. Since Portugal presents a lower immigrant-associated TB incidence rate when compared to other European countries, we sought to characterize the epidemiology and transmission dynamics among the foreign-born population coming from Portuguese-speaking countries that are associated with higher TB incidences. In the present study we analyzed 133 Mycobacterium tuberculosis isolates obtained from foreign-born individuals over a three-year period in Lisbon, Portugal, using molecular epidemiological methods such as spoligotyping and 24-loci MIRU-VNTR. Moreover, all strains were subjected to drug susceptibility testing. The genetic profiles obtained suggest that strain importation from Portuguese speaking countries plays a less important role in TB epidemiology but instead argue in favor of a high degree of penetrance of Portuguese endemic strains to the migrant population, including multidrug resistant strains, which is particularly relevant to active screening programs.
- Long-Term Evolution of SARS-CoV-2 in an Immunocompromised Patient with Non-Hodgkin LymphomaPublication . Borges, Vítor; Isidro, Joana; Cunha, Mário; Cochicho, Daniela; Martins, Luís; Banha, Luís; Figueiredo, Margarida; Rebelo, Leonor; Trindade, Maria Céu; Duarte, Sílvia; Vieira, Luís; Alves, Maria João; Costa, Inês; Guiomar, Raquel; Santos, Madalena; Cortê-Real, Rita; Dias, André; Póvoas, Diana; Cabo, João; Figueiredo, Carlos; Manata, Maria José; Maltez, Fernando; Gomes da Silva, Maria; Gomes, João PauloRecent studies have shown that persistent SARS-CoV-2 infections in immunocompromised patients can trigger the accumulation of an unusual high number of mutations with potential relevance at both biological and epidemiological levels. Here, we report a case of an immunocompromised patient (non-Hodgkin lymphoma patient under immunosuppressive therapy) with a persistent SARS-CoV-2 infection (marked by intermittent positivity) over at least 6 months. Viral genome sequencing was performed at days 1, 164, and 171 to evaluate SARS-CoV-2 evolution. Among the 15 single-nucleotide polymorphisms (SNPs) (11 leading to amino acid alterations) and 3 deletions accumulated during this long-term infection, four amino acid changes (V3G, S50L, N87S, and A222V) and two deletions (18-30del and 141-144del) occurred in the virus Spike protein. Although no convalescent plasma therapy was administered, some of the detected mutations have been independently reported in other chronically infected individuals, which supports a scenario of convergent adaptive evolution. This study shows that it is of the utmost relevance to monitor the SARS-CoV-2 evolution in immunocompromised individuals, not only to identify novel potentially adaptive mutations, but also to mitigate the risk of introducing "hyper-evolved" variants in the community.
- Mycobacterium tuberculosis genetic diversity and drug resistance across Portuguese-speaking countries and CPLP-TB: a novel framework and surveillance tool for the Lusophone communityPublication . Perdigão, João; Silva, Carla; Diniz, Jaciara; Pereira, Catarina; Machado, Diana; Ramos, Jorge; Silva, Hugo; Abilleira, Fernanda; Brum, Clarice; Reis, Ana J.; Macedo, Maíra; Scaini, João L.; Silva, Ana B.; Esteves, Leonardo; Macedo, Rita; Maltez, Fernando; Clemente, Sofia; Coelho, Elizabeth; Viegas, Sofia; Rabna, Paulo; Rodrigues, Amabélia; Taveira, Nuno; Jordão, Luísa; Kritski, Afrânio; Lapa e Silva, José; Mokrousov, Igor; Couvin, David; Rastogi, Nalin; Couto, Isabel; Pain, Arnab; McNerney, Ruth; Clark, Taane G.; von Groll, Andrea; Dalla-Costa, Elis R.; Rossetti, Maria Lúcia; da Silva, Pedro E.A; Viveiros, Miguel; Portugal, IsabelBackground: Tuberculosis (TB) remains a major health problem within the Community of Portuguese Language Speaking Countries (CPLP). Despite the marked variation in TB incidence across its member-states and continued human migratory flux between countries, a considerable gap in the knowledge on the Mycobacterium tuberculosis population structure and strain circulation between the countries still exists. Materials and Methods: To address this, we have assembled and analyzed the largest CPLP M. tuberculosis molecular and drug susceptibility dataset, comprised by a total of 1447 clinical isolates, including 423 multidrug-resistant isolates, from five CPLP countries. Genotyping analysis was carried out by 15/24 Mycobacterial Interspersed Repetitive Unit – Variable Number of Tandem Repeat (MIRU-VNTR) and Spoligotyping. Drug Susceptibility testing was performed using standardized BACTEC 960 MGIT methodology or through the resazurin microtiter assay (REMA). Results: The data herein presented reinforces Latin American and Mediterranean (LAM) strains as the hallmark of M. tuberculosis populational structure in the CPLP coupled with country-specific differential prevalence of minor clades. Moreover, using high-resolution typing by 24-loci MIRU-VNTR, six cross-border genetic clusters were detected, thus supporting recent clonal expansion across the Lusophone space. To make this data available to the scientific community and public health authorities we developed CPLP-TB (available at http://cplp-tb.ff.ulisboa.pt), an online database coupled with web-based tools for exploratory data analysis. Conclusions: As a public health tool, CPLP-TB is expected to contribute to improved knowledge on the M. tuberculosis population structure and strain circulation within the CPLP, thus supporting risk assessment of strain-specific trends.
- Ongoing outbreak of hepatitis A associated with sexual transmission among men who have sex with men, Portugal, October 2023 to April 2024Publication . Rosendal, Ebba; von Schreeb, Sebastian; Gomes, Alexandre; Lino, Sara; Grau-Pujol, Berta; Magalhães, Sara; Ricoca Peixoto, Vasco; Roque, Carla; Moreno, Joana; Maltez, Fernando; Almeida, Fernando; Sá Machado, Rita; Marinho, Rui Tato; Vasconcelos, Paula; de Sousa, Rita; Vieira Martins, JoãoAn outbreak of hepatitis A is ongoing in Portugal, with 71 confirmed cases from 7 October 2023 to 24 April 2024. Most cases are male, aged 18-44 years, with many identifying as men who have sex with men (MSM) and reported as suspected sexual transmission. Phylogenetic analysis identified the subgenotype IA, VRD 521-2016 strain, last observed in an MSM-associated multi-country outbreak in 2016 to 2018. We wish to alert colleagues in other countries to investigate potential similar spread.
- Unraveling Mycobacterium tuberculosis genomic diversity and evolution in Lisbon, Portugal, a highly drug resistant settingPublication . Perdigão, João; Silva, Hugo; Machado, Diana; Macedo, Rita; Maltez, Fernando; Silva, Carla; Jordão, Luísa; Couto, Isabel; Mallard, Kim; Coli, Francesc; Hill-Cawthorne, Grant A.; McNerney, Ruth; Pain, Arnab; Clark, Taane G.; Viveiros, Miguel; Portugal, IsabelBACKGROUND: Multidrug- (MDR) and extensively drug resistant (XDR) tuberculosis (TB) presents a challenge to disease control and elimination goals. In Lisbon, Portugal, specific and successful XDR-TB strains have been found in circulation for almost two decades. RESULTS: In the present study we have genotyped and sequenced the genomes of 56 Mycobacterium tuberculosis isolates recovered mostly from Lisbon. The genotyping data revealed three major clusters associated with MDR-TB, two of which are associated with XDR-TB. Whilst the genomic data contributed to elucidate the phylogenetic positioning of circulating MDR-TB strains, showing a high predominance of a single SNP cluster group 5. Furthermore, a genome-wide phylogeny analysis from these strains, together with 19 publicly available genomes of Mycobacterium tuberculosis clinical isolates, revealed two major clades responsible for M/XDR-TB in the region: Lisboa3 and Q1 (LAM).The data presented by this study yielded insights on microevolution and identification of novel compensatory mutations associated with rifampicin resistance in rpoB and rpoC. The screening for other structural variations revealed putative clade-defining variants. One deletion in PPE41, found among Lisboa3 isolates, is proposed to contribute to immune evasion and as a selective advantage. Insertion sequence (IS) mapping has also demonstrated the role of IS6110 as a major driver in mycobacterial evolution by affecting gene integrity and regulation. CONCLUSIONS: Globally, this study contributes with novel genome-wide phylogenetic data and has led to the identification of new genomic variants that support the notion of a growing genomic diversity facing both setting and host adaptation.