Correction: Population dynamics of a salmonella lytic phage and its host: implications of the host bacterial growth rate in modelling

Correction.The Fig 1 Figure Legend is incorrect. The authors have provided a corrected version here

The use of antibiotics to improve phage detection and enumeration by the double-layer agar technique

<p>Abstract</p> <p>Background</p> <p>The Double-Layer Agar (DLA) technique is extensively used in phage research to enumerate and identify phages and to isolate mutants and new phages. Many phages form large and well-defined plaques that are easily observed so that they can be enumerated when plated by the DLA technique. However, some give rise to small and turbid plaques that are very difficult to detect and count. To overcome these problems, some authors have suggested the use of dyes to improve the contrast between the plaques and the turbid host lawns. It has been reported that some antibiotics stimulate bacteria to produce phages, resulting in an increase in final titer. Thus, antibiotics might contribute to increasing plaque size in solid media.</p> <p>Results</p> <p>Antibiotics with different mechanisms of action were tested for their ability to enhance plaque morphology without suppressing phage development. Some antibiotics increased the phage plaque surface by up to 50-fold.</p> <p>Conclusion</p> <p>This work presents a modification of the DLA technique that can be used routinely in the laboratory, leading to a more accurate enumeration of phages that would be difficult or even impossible otherwise.</p

Exploiting the proteins encoded in the genome of the broad host range Salmonella phage PVP-SE1

Foodborne diseases are of major concern due to its worldwide impact. Salmonella has been constantly pointed as the second leading cause constituting thus a major public health burden with significant impact in the society costs. The increased resistance of bacteria toward antimicrobials and the recent legislation restricting the use of antibiotics as growth promoters in animal production requires alternatives to the use of antibiotics in the control of this zoonotic pathogen. Consequently, there is an urgent need to control this bacterial genus. To accomplish this, fast and accurate techniques for early detection are also required. Bacteriophages (phages) as natural predators of bacteria offer a great potential for pathogens detection and control due to their high specificity and killing ability. We have isolated and characterize a broad host range phage with great potential for Salmonella control. This phage encodes several proteins with great biotechnological potential which include the phage tail fibers with application in Salmonella detection, peptidoglycan hydrolases and holins that produce lysis of the bacterial cells and depolymerases which can decrease the ability of the cells to form biofilms and consequently decrease resistance of the cells to treatment. In this work we will identify these proteins and envisage their biotechnological

Interpretation of gravity data to delineate structural features connected to low-temperature geothermal resources at Northeastern Portugal

A great number of low-temperature geothermal fields occur in Northern-Portugal related to fractured rocks. The most important superficial manifestations of these hydrothermal systems appear in pull-apart tectonic basins and are strongly conditioned by the orientation of the main fault systems in the region. This work presents the interpretation of gravity gradient maps and 3D inversion model produced from a regional gravity survey. The horizontal gradients reveal a complex fault system. The obtained 3D model of density contrast puts into evidence the main fault zone in the region and the depth distribution of the granitic bodies. Their relationship with the hydrothermal systems supports the conceptual models elaborated from hydrochemical and isotopic water analyses. This work emphasizes the importance of the role of the gravity method and analysis to better understand the connection between hydrothermal systems and the fractured rock pattern and surrounding geology. (c) 2013 Elsevier B.V. All rights reserved

New bacterial biorecognition elements from phage origin

Book of Abstracts of CEB Annual Meeting 2017info:eu-repo/semantics/publishedVersio

Long-Term Trends in the Incidence of Peritoneal Dialysis-Related Peritonitis Disclose an Increasing Relevance of Streptococcal Infections: A Longitudinal Study

[Abstract} Background. The selective impact of strategies for prevention of PD-related peritonitis (PDrP) may have modified, in the long term, the causal spectrum, clinical presentation and outcomes of these infections. Objectives. To compare trends in the incidence of PDrP by different microorganisms during a 30-year period, with a particular focus on streptococcal infections. To analyze the clinical presentation and outcomes of these infections. Secondarily, to investigate how the isolation of different species of streptococci can influence the clinical course of PDrP by this genus of bacteria. Method. Following a retrospective, observational design we investigated 1061 PDrP (1990–2019). We used joinpoint regression analysis to explore trends in the incidence of PDrP by different microorganisms, and compared the risk profile (Cox), clinical presentation and outcomes (logistic regression) of these infections. Main results. Our data showed a progressive decline in the incidence of PDrP by staphylococci and Gram negative bacteria, while the absolute rates of streptococcal (average annual percent change +1.6%, 95% CI -0.1/+3.2) and polymicrobial (+1.8%, +0.1/+3.5) infections tended to increase, during the same period. Remarkably, streptococci were isolated in 58.6% of polymicrobial infections, and patients who suffered a streptococcal PDrP had a 35.8% chance of presenting at least one other infection by the same genus. The risk profile for streptococcal infections was comparable to that observed for PDrP overall. Streptococcal PDrP were associated with a severe initial inflammatory response, but their clinical course was generally nonaggressive thereafter. We did not observe a differential effect of different groups of streptococci on the clinical presentation or outcome of PDrP. Conclusions. Time trends in the incidence of PDrP by different microorganisms have granted streptococci an increasing relevance as causative agents of these infections, during the last three decades. This behaviour suggests that current measures of prevention of PDrP may not be sufficiently effective, in the case of this genus of microorganisms

design, planning and implementation

Background: In Health Examination Surveys interview information is complemented with objective information, providing more accurate indicators than self-reported data. We report the study design, planning and implementation of the first Portuguese Health Examination Survey (INSEF). Methods: INSEF was a cross-sectional population-based study representative at regional and national level. Individuals aged between 25 and 74 years old, residing in Portugal were selected from the national health users' registry through multi-stage stratified probabilistic sampling. Sample size was set at 4200 individuals. Data was collected in primary care units and included blood pressure, height, weight, hip and waist measurements, blood collection for lipid profile, HbA1c and blood count and a general health questionnaire. European HES procedures were followed. Results: A total of 4911 individuals agreed to participate (43.9% participation rate). Participation rate varied by region, sex and age group, being lower in Lisbon and Tagus Valley (32.8%), for men (41.8%) and for those aged 25-34 years old (36%). Conclusions: INSEF has set up an experienced national and regional structure for HES implementation. Nationally representative quality epidemiological data is now available for public health monitoring, planning and research.publishe

EAIR 41st Annual Forum in Leiden, The Netherlands 25 till 28 August 2019

Trabalho apresentado em EAIR 41st Annual Forum, 25-28 agosto 2019, Leiden, Países Baixos.Polytechnic Institutes in Portugal: research on the impact of twelve institutes on the local economy Higher Education Institutions are recognized as important actors in regional development. The Portuguese higher education system comprises both Universities and Polytechnic Institutes, which face an increasing pressure to demonstrate that their presence has an impact on the surrounding communities contributing to their economic development. This paper presents the estimation of the economic impact of twelve Polytechnic Institutes, located in quite diverse regions, based on a shared model so that comparisons have a collective framework of analysis. The main results obtained show that the economic impact ranged from 1.8% to 10.6% of the local GDP and that these Institutes are major local employers.info:eu-repo/semantics/publishedVersio

Viral genetic clustering and transmission dynamics of the 2022 mpox outbreak in Portugal

Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.info:eu-repo/semantics/publishedVersio