13 research outputs found
Preliminary studies on the role of mazEF in S. epidermidis biofilms dormancy
Background: Staphylococcus epidermidis has been recognized as one of the main causes of nosocomial infections, mainly due to its ubiquitous presence on human skin and mucous membranes and capacity to form biofilms on the surface of indwelling medical devices. S. epidermidis biofilm-associated infections are a major concern since biofilms present higher antimicrobial tolerance and ability to evade host immune defenses, often resulting in recurrent and relapsing infections. Importantly, some bacteria within biofilms have been found to enter a dormancy state, presenting less sensitivity to host immune response and antimicrobial therapy. Moreover, it was earlier found that mazE, a gene encoding a protein of the mazEF complex, was only expressed in situations where dormancy was induced. Thus, the aim of the study was to analyze the role of mazEF in S. epidermidis biofilm dormancy.This study was supported by the Portuguese Foundation for Science and Technology (FCT) by the funded project PTDC/BIA-MOL/29553/2017, under the scope of COMPETE2020 (POCI-01-0145- FEDER-029553) and by the strategic funding of unit UID/BIO/04469/2019.info:eu-repo/semantics/publishedVersio
Prevalence of diabetes-associated gene variants and its association with blood glucose levels in the Algarve population, Portugal
The global rise in incidence of type 2 (T2D) has been called a pandemic, constituting a major public health concern.
Although environmental factors play a substantial role in the etiology of T2D, genetic susceptibility has been
established as a key component in T2D risk. Given the absence of studies regarding the prevalence of T2D associated
variants in the Portuguese population, our aim was to determine the prevalence of disease-associated variants and
determine its relative contribution to this phenotype. For this purpose, we have recruited 221 individuals (93 males
and 128 females), between 26-91 years old (mean age 57.1), who were enrolled in the Health Centre of S. Brás de
Alportel (Algarve). For each participant, we have measured total glucose levels and collected DNA. In addition, each
participant has answered an exhaustive questionnaire including socio-demographic information, health history and
lifestyle. We have selected and analysed three of the most significant loci previously reported to be associated with
T2D in Caucasian populations (TCF7L2 rs7903146, PARPG rs1801282 and FTO rs9939609) and performed an
association analysis between glucose levels in this population and the selected gene variants. The mean total
population glucose level was 103.85±35.3 g/dl. We found a significant difference in the mean glucose levels between
males (mean = 111.5±51.3 g/dl) and females (mean = 98.4±17.6 g/dl) (Mann-Whitney test P < 0.001). The relative
allele frequencies of the genotyped variants have been established. Genotype distribution for all investigated SNPs
was in Hardy-Weinberg equilibrium. We found a marginal association between glucose levels and genotypes at the
TCF7L2 locus (Mann-Whitney test P = 0.045) in females but not in males, with carriers of the T allele displaying
higher levels of blood glucose than homozygous for the A allele. This difference is also observed in males, although
not reaching significance. No association was found between glucose levels and the other genotyped variants. These
results suggest that the pathophysiology of the disease may be different between males and females, or that
environmental factors are influencing this trait in males. We are currently investigating the later hypothesis by
increasing our sample size and by analysing lifestyle information provided by the participants in order to evaluate
gene-environment interactions influencing glucose levels in the Portuguese population.The pilot study of the Portuguese Component of the European Health
Examination Survey (EHES) project has received funding from the European
Commission/DG Sanco (Agreement number: 20092301 – EHES JA – EAHC). This
study has also received funding from the Portuguese Foundation for Science
and Technology (FCT) (Project Reference: PTDC/SAU-ESA/101743/2008)
Genetic variation at the CY2C19 gene associated with Metabolic Syndrome susceptibility in a South Portuguese population
Metabolic syndrome (MetS) is a cluster of conditions — increased blood pressure, high blood glucose level, excess body fat around the waist and abnormal cholesterol levels — that occur together, increasing the risk of heart disease, stroke and diabetes. In Portugal, the MetS prevalence is estimated to be 27,5% with regional variations, being highest in the Alentejo (30,99%) and lowest in the Algarve (24,42%), constituting a public health problem.
Although for clinical settings, a binary definition of MetS enabling a yes or no diagnosis is useful, it is clear that dichotomizing a continuous outcome variable reduces the statistical power of the MetS association studies. Therefore, the aim of the present study is to identify genetic risk factors involved in MetS etiology, using a continuous MetS score. To achieve our goal, a principal component analysis was performed to compute a score using the six normalized risk factors for MetS (waist circumference, diastolic and systolic blood pressure, glucose, triglycerides and HDL blood levels), with a higher MetS score indicating a less favorable MetS profile. After calculating this score, an association study was performed using 37 SNPs in candidate genes involved in MetS related diseases. A total of 206 subjects, including 119 women and 87 men (mean age: 56,31± 16,37 years, range: 26-91 years) were included in this analysis. We found 4 SNPs significantly associated with higher MetS scores (rs4244285 (CYP2C19), rs279871 (GABRA2), rs1647 (NPY) and rs1142345(TPMT)). P-values are 4,36x10-4, 1,3x10-2, 1,7x10-2 and 9,76x10-3 respectively. After correcting for multiple testing only rs4244285 (CYP2C19) remains significant (p=0,016). In addition, we have performed a multiple regression analysis considering the CYP2C19 genotype as the independent variable, adjusted for age. The resulting model explains 17% of the MetS score variance. After adding the remaining SNP genotypes that do not survive the multiple testing correction, the same model is able to explain 23,1% of the score. Our findings support the evidence of an association between CYP2C19 rs4244285 gene polymorphism and the MetS score, emphasizing the importance of lipid metabolism, thought cytochrome P450 enzymes, in the MetS etiology. However, further studies will be necessary to replicate these findings in different populations as well as functional studies to clarify the role of this variant in the etiology of MetS.The pilot study of the Portuguese Component of the European Health
Examination Survey (EHES) project has received funding from the European
Commission/DG Sanco (Agreement number: 20092301 – EHES JA – EAHC). This
study has also received funding from the Portuguese Foundation for Science
and Technology (FCT) (Project Reference: PTDC/SAU-ESA/101743/2008)
local problem solving in the Portuguese Health Examination Survey: a mixed method study
UIDB/04647/2020 UIDP/04647/2020Background Participation rates in health surveys, recognized as an important quality dimension, have been declining over the years, which may affect representativeness and confidence in results. The Portuguese national health examination survey INSEF (2015) achieved a participation rate of 43.9%, which is in line with participation rates from other similar health examination surveys. The objective of this article is to describe strategies used by the local teams to increase participation rates and to solve practical survey problems. Methods After a literature search, informal interviews were conducted with 14 public health officials from local health examination teams, regional and central authorities. 41 of the local staff members also filled in a short questionnaire anonymously. The interviews and self-administered questionnaires were analysed using mixed methods, informed by thematic analysis. Results The local teams believed that the detailed manual, described as a "cookbook for making a health examination survey", made it possible to maintain high scientific standards while allowing for improvising solutions to problems in the local context. The quality of the manual, supported by a series of training workshops with the central research and support team, gave the teams the confidence and knowledge to implement local solutions. Motivation and cohesion within the local teams were among the goals of the training process. Local teams felt empowered by being given large responsibilities and worked hard to incite people to attend the examination through a close and persuasive approach. Local teams praised their INSA contacts for being available for assistance throughout the survey, and said they were inspired to try harder to reach participants to please their contacts for interpersonal reasons. Conclusions The theory of organizational improvisation or bricolage, which means using limited resources to solve problems, was useful to discuss and understand what took place during INSEF. A detailed manual covering standard procedures and face-to-face workshops, including role-play, were vital to assure high scientific standards and high participation rates in this health examination survey. Close contacts between the central team and local focal points in all regions and all survey sites were key to accommodating unexpected challenges and innovative solutions.publishersversionpublishe
Fatigue Resistance and Cracking Mechanism of Concrete Pavements Reinforced with Recycled Steel Fibres Recovered from Post-consumer Tyres
Recycled steel fibres recovered from post-consumer tyres can be used as reinforcement in concrete to enhance its post-cracking flexural behaviour and may also improve its fatigue behaviour. This paper aims to examine the use of recycled steel fibres as fatigue reinforcement for concrete pavements, based on an experimental investigation. Concrete prisms were subjected to cyclic third-point flexural loads at a frequency of 15. Hz, at maximum stress levels of 0.5, 0.7 and 0.9. Two types of mixes, conventional and roller compacted concrete, and two recycled fibre contents, 2% and 6% by mass of concrete were used. Unreinforced and industrially produced fibre reinforced concrete mixes were also tested for comparison purposes. The recycled fibres were found to improve the fatigue behaviour of concrete, especially for conventional plastic concrete mixes. Recycled fibres improve fatigue by restraining the propagation of micro-cracks into meso and macro-cracks, whilst industrially produced fibres are more efficient at arresting macro-cracks. For enhanced fatigue performance, it is recommended that recycled fibres should be used in combination with industrially produced fibres. Predictive models are developed using a probabilistic approach. The results show that the use of recycled steel fibres may contribute to a reduction of up to 26% of pavement thickness, when considering the influence of fatigue alone. © 2012 Elsevier Ltd
codY and pdhA expression is induced in Staphylococcus epidermidis biofilm and planktonic populations With higher proportions of viable but non-culturable cells
The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fcimb.2021.771666/full#supplementary-materialStaphylococcus epidermidis biofilm cells can enter a physiological state known as viable but non-culturable (VBNC), where, despite being alive, they do not grow in conventional laboratory media. As such, the presence of VBNC cells impacts the diagnosis of S. epidermidis biofilm-associated infections. Previous transcriptomics analysis of S. epidermidis strain 9142 biofilms with higher proportions of VBNC cells suggested that the genes pdhA, codY and mazEF could be involved in the induction of the VBNC state. However, it was previously demonstrated that VBNC induction is strain-dependent. To properly assess the role of these genes in VBNC induction, the construction of mutant strains is necessary. Thus, herein, we assessed if VBNC cells could be induced in strain 1457, a strain amenable to genetic manipulation, and if the previously identified genes were involved in the modulation of the VBNC state in this strain. Furthermore, we evaluated the formation of VBNC cells on planktonic cultures. Our results showed that despite being commonly associated with biofilms, the proportion of VBNC cells can be modulated in both biofilm and planktonic cultures and that the expression of codY and pdhA was upregulated under VBNC inducing conditions in both phenotypes. Overall, our study revealed that the formation of VBNC cells in S. epidermidis is independent of the mode of growth and that the genes codY and pdhA seem to be relevant for the regulation of this physiological condition.This work was supported by the Portuguese Foundation for Science and Technology (FCT) by the funded project PTDC/BIA-MOL/29553/2017, under the scope of COMPETE2020 (POCI-01-0145-FEDER-029553) and by the strategic funding of unit UIDB/04469/2020. VG and NL acknowledge the support of FCT individual fellowships [SFRH/BD/131452/2017 and SFRH/BD/136998/2018], respectively.info:eu-repo/semantics/publishedVersio
Prevalence of anemia in the Portuguese adult population: results from the first National Health Examination Survey (INSEF 2015)
Aims: Anemia is a global public health problemwith relevant adverse health, social and economic consequences. The objective of this study was to analyze the distribution of the prevalence of anemia in the Portuguese population.
Methods: This is a cross-sectional population-based study, based on the first Portuguese National Health Examination Survey (INSEF), which included 4812 participants aged 25 to 74 years, with data on hemoglobin levels and self-reported diagnosis of anemia. The socioeconomic status of participants was assessed by education level, employment status and material deprivation.
The association between socioeconomic factors and anemia was estimated by adjusted prevalence ratios.
Results: The prevalence of anemia overall was 5.8%, 3.1% in men and 8.4% in women. The overall prevalence of moderate–severe anemia was 1.1%. Previously undiagnosed cases represented 92.5%. In men, anemia was associated with age, education, occupation and material deprivation, and in women, with age group and urban typology.
Conclusion: Anemia represents a relevant public health issue in Portugal. In women, it is more prevalent among those of childbearing age and older, and in men among older individuals of low socioeconomic status. This information is relevant for developing targeted strategies aimed at the prevention, diagnosis and treatment of anemia.This work was supported by the Public Health
Initiatives Program within the European Economic Area Financial
Mechanism (EEA Grants) 2009-2014, and by the Portuguese
Government.info:eu-repo/semantics/publishedVersio