DDI - Posters/abstracts em congressos internacionais
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- 2014/2015 Influenza season in an inland portuguese regionPublication . Almeida, Sofia; Rodrigues, Débora; Gouveia, Paula; Paulo, Sandra; Faria, Conceição; Pechirra, Pedro; Costa, Inês; Cristóvão, Paula; Guiomar, RaquelInfluenza surveillance is an important tool to identify emerging/reemerging strains, and defining seasonality of the circulating strains. The aim of this work is to compare the circulating strains detected by Centro Hospitalar da Cova da Beira, EPE,(CHCB) from an inland north region of Portugal, with the strains circulating among Europe during2014/2015 Influenza season. In the present review, 249 nasofaringeal swabs received in were analized by real time PCR techniques, designed to amplify Influenza A and Influenza B virus. All the positive samples were sent to the Portuguese reference Laboratory in order to subtype influenza A virus and to perform genetic and antigenic characterization of the detected viruses. During 2014/2015 season, a total of 109 positive cases (62 Influenza A and 47 Influenza B) - were detected in the studied region. In the present season, all seasonal types/subtypes of influenza virus circulated, inspite of low level circulation of the Influenza A(H1)pdm strain (~5%of the positive samples, circulating between 6/2015-9/2015 weeks). A(H3) and B strains co-circulated between weeks 1/2015 and 11/2015 with peak activity in weeks 6 and 7/2015. Influenza A, excluding A(H1)pdm, was responsible for 47% of positive cases, mainly in the last 6 weeks. Influenza B strains were responsible for 42% of positive Influenza cases, mainly in the first 7 weeks of the year. All influenza B strains characterized by the Portuguese National Laboratory were from B/Yamagata lineage. 19% of influenza B strains wereselected for genetic characterization, all were similar to B/Phuket/3073/2013 (clade 3). At the date of submission of the abstract, only 8 Influenza A strains were genetically characterized, 5 belonged to genetic subgroup 3C.2a, represented by A/Hong Kong/5738/2014, dissimilar to the current A(H3N2) vaccine strain and 3 belonged to A/Samara/73/2013 (genetic group 3C.3), antigenically similar to the current A(H3N2) vaccine The co-circulation of influenza types/subtypes was similar to the one described in Europe, but in this Portuguese region, the Influenza B circulated in first part of the epidemic period, followed by A(H3) virus at the end of epidemic period.. The genetic characterization observed in Portugal was similar to the one from ECDC data for Influenza B. Relatively to Influenza A, the majority of detected viruses were dissimilar to the 2014/2015 A(H3) vaccine virus, being a higher proportion than the observed in Europe, but more data is needed to achieve any conclusion.
- Accessing occupational exposure to fungi in a cork industryPublication . Viegas, C.; Clérigo, A.; Faria, T.; Sabino, Raquel; Veríssimo, Cristina; Quintal-Gomes, A.; Viegas, S.In this study we aimed to access fungal exposure in workers from one cork industry through the mycological analysis of their nasal exudate and the environmental fungal contamination of their surroundings as well. Nasal mucous samples from 127 workers were taken with sterilized cotton swabs.The fungal species identified in the collected nose swabs were shown to be correlated with the results obtained in the environment. Eighty workers (63.0%) presented contamination of their nose nostril with Chrysonilia sitophila, which number of colonies was countless. Within the Aspergillus genus, the complexes Fumigati, Circumdati, Versicolores and Candidi were isolated. No azole-resistant Aspergillus isolates grew in the selective media used (screened itraconazole and voriconazole resistance).This approach allowed us to estimate the risk associated with these tasks performance. Moreover, the cork industry is related to high dust contamination and this can promote exposure to fungi since dust particles can act as carriers of fungi to the worker’s nose. Assessment by molecular tools will ensure the specific targeting of DNA from P. glabrum complex in workers nose.
- Actividade antibacteriana de extractos de Planktothrix agardhii contra Staphylococcus aureusPublication . Menezes, Carina; Dias, ElsaA resistência de bactérias patogénicas à antibioterapia é um dos principais problemas de saúde pública, face à crescente ineficácia dos antibióticos no tratamento de doenças infeciosas. Assim, a pesquisa de novos antibióticos é um importante desafio da investigação em saúde. O potencial farmacológico de cianobactérias tem sido avaliado e descrito, mas, no entanto, ainda não há nenhum composto cianobacteriano que tenha sido aprovado pelas autoridades do medicamento como agente antibacteriano. Neste trabalho avaliámos a atividade de extratos de 40 estirpes de Planktothrix agardhii contra duas bactérias patogénicas: Klebsiella pneumonia e Staphylococus aureus. Para cada espécie bacteriana alvo usou-se uma estirpe de referência (ATCC) e uma estirpe clínica, isolada a partir de amostras de pacientes e estudadas no Laboratório de Resistência aos Antibióticos e Infeções Associadas aos Cuidados de Saúde. As estirpes de P. agardhii foram isoladas de albufeiras portuguesas e têm sido mantidas na coleção “Estela Sousa e Silva Algae Culture Collection” do Laboratório de Biologia e Ecotoxicologia. A biomassa de P. agardhii (200mg) foi extraída com metanol (70%, 10mL/100mg) overnight e sujeita a ciclos de sonicação. O metanol dos extratos foi evaporado e os extratos aquosos resultantes foram purificados em cartuchos C18. A atividade dos extratos contra as bactérias K. pneumonia e S.aureus foi avaliada através do método da Difusão em Disco (EUCAST), usando discos impregnados com 2, 4, 6, 8 e 10 mg de cada extrato. De acordo com os resultados preliminares, nenhum dos extratos apresenta atividade contra K. pneumonia, mas o extrato de P. agardhii LMECYA 256 apresenta um ligeiro halo de inibição relativamente às estirpes de S. aureus, de uma forma aparentemente dependente da dose de extrato aplicada. O S. aureus é uma bacteria Gram-positiva, frequentemente associada a uma vasta gama de patologias, desde simples infeções na pele, até infeções graves como pneumonia e meningite. Assim, revela-se do maior interesse explorar as propriedades antibacterianas de cianobactérias, designadamente do género Planktothrix, contribuindo, desta forma, para um dos desafios atuais da ciência: a identificação de novos antibióticos de origem natural.
- Activity of Diphenyl diselenide against Aspergillus isolatesPublication . Melo, Aryse Martins; Poester, Vanice Rodrigues; Munhoz, Lívia; Trápaga, Mariana; Roca, Beatriz; Klafke, Gabriel Baracy; Sabino, Raquel; Stevens, David A.; Xavier, Melissa OrzechowskiOrganoselenium compounds have been showing promising antimicrobial activity against bacteria and some fungal species. Among these compounds, diphenyl diselenide (PhSe)2 is a simple and chemically stable molecule with proven low toxicity to animal hosts. Although the mechanisms of action of this molecule are not totally clear, it has been reported that it has a prooxidative activity for microorganisms, due to glutathione depletion. Given the emergence of azole resistance Aspergillus sp. isolates is a global and rising concern, research towards new molecules with antifungal potential are necessary. Thus, the aim of this study was to evaluate the in vitro susceptibility of Aspergillus spp. clinical isolates to (PhSe)2.
- Adenoids, friends or foes?Publication . Subtil, João; Lavado, Paula; Rodrigues, João; Rodrigues, Lúcia; Nogueira, Isabel; Duarte, Aida; Jordao, LuisaThe main goal of this study is to evaluate the existence of a link between biofilm assembly on adenoids and the incidence of recurrent infections within a paediatric population. Thirty-three different bacterial genera were isolated from 186 samples (nasal/adenoid scrubs and adenoid biopsies) being Haemophilus, Neisseria, Streptococcus and Staphylococcus the most frequent. Biofilms were present in 27.4% of the adenoid samples as assessed by SEM. Since the aim of the study is to assess the role of biofilms on adenoid colonization/ invasion and onset of infection a group of samples harbouring clinically relevant bacteria (H.influenzae, S. aureus, S. pyogenes, S. pneumococcus and Moraxella) both on the adenoid surface and core were selected for further studies. Based on biofilm assembly in vitro, assessed by crystal violet assay, bacteria were classified as weak, moderate and strong biofilm assemblers. No direct relation between the ability to assemble biofilms in vitro and the presence of biofilms on the adenoid (biofilm in vivo) was found. A similar result was obtained for antibiotic susceptibility with the majority of bacteria being antibiotic susceptible independently of its origin (sample with or without biofilms). This result might be explained at least partially, by the nature of the sample since the adenoidectomy can only be performed in individuals without infection. H. influenzae, the most isolated bacterium, is an opportunistic pathogen, highly adapted to colonize the upper respiratory tract and easily progresses to infection, especially in children. For this reason, virulence factors such as the capsular type were investigated by PCR. However, all strains were characterized as non-capsulated, which might explain adenoid colonization and biofilm formation, as have been also described in the literature. Further studies must be performed to validate the thesis that adenoids function as a reservoir of etiologic agents of respiratory and ear infections.
- Aetiology of Acute Gastroenteritis in Hospitalized Children from Lisbon AreaPublication . Costa, Inês; Júlio, Cláudia; Rodrigues, João; Machado, Jorge; Correia, Cristina; Oliveira, Maria Marisa; Escobar, Carlos; Costa, Beatriz; Brito, Maria João; Correia, Paula; Ferreira, Gonçalo Cordeiro; Simões, Maria João; Oleastro, MónicaGastroenteritis is a major cause of morbidity and mortality worlwide. Aim: Determine the etiology of gastroenteritis in a cohort of children hospitalized Methods: From May 2011 to January 2012, stool samples were collected from children (4.2 ± 4.8 years). Viral agents (enteric and enterovirus) were detected by RT-PCR. Stool specimens were also tested for bacteria and parasites, by conventional methods. Results: From the 82 stool samples, 42(51.2%) were positive for virus, 22 (26.8%) for bacteria and 35.6% (26/73) for parasites. An association between viral infection and age<3 years (OR=4.92, p<0.01) was observed. Distribution of viral agents was NorovirusII (33.3%), Enterovirus (31%), Rotavirus (23.8%), Adenovirus (9.5%), NorovirusI (2.4%). Simultaneous detection of two viral agents was observed in seven cases (16.7%) - NorovirusII and Enterovirus was the most frequent (57.1%); association with another agent was detected in 33.3% samples. Eight of 22 samples (36.4%) were positive for Campylobacter jejuni, 5 (22.7%) for Salmonella spp, 7 (31.8%) for E. coli, although always in co-infection with another agent, and 1 (4.5%) for Shigella spp. 38.5% of the samples were positive for Cryptosporidium spp., 23.1% for Giardia sp. and 3.8% for Entamoeba histolytica. 69.2% of the parasites were co-detected with other agents. Conclusion: Results suggest that viral agents are the most common among children with acute gastroenteritis, although co-infections with bacteria and parasites are frequent. The most common viral agent associated with acute diarrhea was NorovirusII. An important percentage of cases with no infectious aetiology identified, suggesting that other emergent agents are probably implicated.
- An insight into the transcriptome of Rhipicephalus bursa: differential gene expression upon feeding and in response to salivary glands infection with Babesia ovisPublication . Couto, J.; Antunes, S.; Ferrolho, J.; Santos, A.S.; Santos-Silva, M.M.; de la Fuente, J.; Domingos, A.Understanding the paradigm of the pathogen-tick-host triad remains an intricate issue. Basic research focusing on each one of these interplays is necessary to better comprehend this dynamic system. One of such complex association is the Babesia ovis, transmitted by the Rhipicephalus bursa ticks. B. ovis is an intra-erythrocytic protozoan parasite highly pathogenic parasite, causing severe infection in sheep. Pathogen and vector co-evolved and during infection a substantial molecular dialogue/interchanges takes place. The pathogen is adapted to both its hosts, and remarkably transovarial and transstadial transmissions are present in the vector. In ticks, the salivary glands (SG) play important role in both, feeding and pathogen interaction, being a vehicle for pathogen transmission and a barrier that they need to surpass.
- Analysis of Aspergillus spp. burden by culture and molecular based methods in different occupational environments: what needs to be done?Publication . Quintal Gomes, Anita; Faria, Tiago; Caetano, Liliana Aranha; Sabino, Raquel; Viegas, CarlaFungal burden have traditionally being detected by conventional culture analysis, which despite its limitations, is widely used by the scientific community. Alternatively, quantitative real-time PCR (qPCR), based on the amplification of genomic regions specific to certain fungal species, has been associated with increased sensivity, allowing the detection of dormant forms of fungi, such as spores. We present several studies where both methods were used to detect the presence of toxigenic fungi, namely Aspergillus, particularly from the Fumigati, Flavi and Circumdati sections
- Analysis of longitudinal nef sequence variation throughout HIV-2 infectionPublication . Remédios, M.; Paixão, E.; Feliciano, H.; Silva-Graça, A.; Pádua, E.Background: Human Immunodeficiency Virus type 1 (HIV-1) and type 2 (HIV-2) may case a severe immunodeficiency in humans (AIDS). However HIV-2 is more frequently associated with lower levels of transmission and disease progression, compared with HIV-1 infections. The role of nef gene in vivo during the development of AIDS has been clearly demonstrated in simian immunodeficiency virus infected Rhesus macaques model, but the determinants which play a role in the pathogenesis of HIV are relatively poorly understood. However, even less is known about the role of nef in HIV-2 infections. Methods: In this study, it was analyzed the variation of 48 nef gene sequences, obtained from samples taken between 1994 and 2009, corresponding to 17 HIV-2-infected individuals with different clinical stages of infection. The sequences obtained by Nested PCR were classified by phylogenetic analysis and the functional protein motifs, described as important in CD4 and MHC-I downregulation and in viral infectivity were also analyzed. Results: In all individuals were identified nef sequences from group A of HIV-2, which encoded possible functional and complete protein. There was a greater conservation of residues in the Nef sequences of individuals in the symptomatic stage (63%), comparatively to individuals in the asymptomatic stage (19%). While some functional motifs (MGxxxS1, DDDD93, RR137 and DD205) and also residues (G128, I141 and L142) remained conserved, others (YSRF39, LRAR21, PxxP101, EE185) revealed changes during the follow-up period. The PxxP motif exhibited wide inter-individual variation in vivo from an HIV-1-like tetra-proline motif (PxxP)3 to disruption of the minimal core PxxPLR motif. The disruption was observed in 11 sequences exclusively from asymptomatic individuals (p=0.021). The sequence motif variation towards tetra-proline configuration was observed in 2 symptomatic individuals during time of infection. The results also revealed the existence of a negative selective pressure, as well as codons under positive pressure in the sequences. Conclusion: In this HIV-2-infected individuals studied, it was observed a need for a greater degree of Nef protein conservation in a symptomatic phase. Sequences altered and potentially critical for the Nef function in vivo, in earlier stages of infection, may contribute at some level to a different pattern in viral pathogenesis and disease progression.
- Antibiotic resistance in freshwater cyanobacteria and associated bacteriaPublication . Dias, Elsa; Dias, Daniela; Ferreira, Eugénia; Manageiro, Vera; Vasconcelos, Vitor; Pereira, Paulo; Caniça, ManuelaObjectives: Cyanobacteria are ubiquitous prokaryotes in aquatic ecosystems and although they can be exposed to antibiotics, their role on water resistome was never investigated. Thus, this work aimed to evaluate the antibiotic susceptibility patterns and resistance mechanisms of cyanobacteria and co-occurring bacteria in order to assess their contribution to the global pool of resistance determinants in freshwater. Methods: We investigated 4 cyanobacterial genera (Microcystis, Aphanizomenon, Anabaena and Planktothrix), previously isolated from freshwater reservoirs, and several bacteria isolated from those cyanobacterial cultures. Antibiotic susceptibility of cyanobacteria was evaluated by microdilution method, under specific culturing conditions, against beta-lactams, aminoglycosides, quinolones, sulfonamides and tetracyclines. Minimum inhibitory concentrations (MIC) were determined according to cyanobacterial cell dentisty (DO, 450nm) and microscopic examination of cultures integrity. Bacteria were identified by 16S sequencing and their susceptibility patterns were determined by disk diffusion, according to SFM 2012 non-specific breakpoints, against the same antibiotics. All strains were subjected to the search of class 1, 2 and 3 integrons and antibiotic resistance genes according to the phenotype. Results: Overall, we observed a great diversity of susceptibility to the tested antibiotics, among the distinct strains. Microcystis showed the lowest susceptibility regarding beta-lactams. Conversely, Microcystis was more susceptible to quinolones, while Planktothrix showed higher MIC values. Bacteria from cyanobacterial cultures were identified as Hydrogenophaga atypica, Limnobacter thioxidans, Rhizobium radiobacter, Sphingobium sp. and Brevundimonas lenta. Even though no known antibiotic resistance genes were yet identified, bacteria from different species and showing distinct phenotypes exhibited class 1 and 2 integrons. L. thioxidans, for example, revealed to be resistant to aminoglycosides and harbored a class 2 integron. Conclusions: Although no known antibiotic resistance genes were found in cyanobacteria and co-occurring bacteria, the presence of integrons and the susceptibility to antibiotics, suggest that they may play a role on freshwater resistome and eventually contribute to the dissemination of antibiotic resistance. These results may also be helpful to define guidelines and breakpoints to access cyanobacteria antibiotic susceptibility.