224 research outputs found

    Identification of Streptococcus pneumoniae by a real-time PCR assay targeting SP2020.

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    Real-time PCR targeting lytA (the major autolysin gene) and piaB (permease gene of the pia ABC transporter) are currently used as the gold-standard culture-independent assays for Streptococcus pneumoniae identification. We evaluated the performance of a new real-time PCR assay - targeting SP2020 (putative transcriptional regulator gene) - and compared its performance with the assays previously described. A collection of 150 pneumococci, 433 non-pneumococci and 240 polymicrobial samples (obtained from nasopharynx, oropharynx, and saliva; 80 from each site) was tested. SP2020 and lytA-CDC assays had the best performance (sensitivity of 100% for each compared to 95.3% for piaB). The specificity for lytA and piaB was 99.5% and for SP2020 was 99.8%. Misidentifications occurred for the three genes: lytA, piaB and SP2020 were found in non-pneumococcal strains; piaB was absent in some pneumococci including a serotype 6B strain. Combining lytA and SP2020 assays resulted in no misidentifications. Most polymicrobial samples (88.8%) yielded concordant results for the three molecular targets. The remaining samples seemed to contain non-typeable pneumococci (0.8%), and non-pneumococci positive for lytA (1.7%) or SP2020 (8.7%). We propose that combined detection of both lytA-CDC and SP2020 is a powerful strategy for the identification of pneumococcus either in pure cultures or in polymicrobial samples

    Alienation and health in adolescents : an original evaluation tool

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    Copyright © 2018 by authors and Open Access Library Inc. This work is licensed under the Creative Commons Attribution International License (CC BY 4.0).The present work aims to construct and validate a tool enabling to evaluate alienation in Portuguese adolescents. Participants were a group of adolescents that participated in the Portuguese survey of the European study Health Behaviour in School-aged Children (HBSC). For this study, only adolescents from the 8th and 10th grades were included in the sample, comprising 3869 students. The results show a good adequacy of the confirmatory factorial analysis (CFA) model. This model revealed 3 subscales proposals—Demotivation, Isolation and Instability, and a full scale—Total Alienation. When analyzed in relation to other variables (gender, grade, wellbeing indicator and risk indicator), the alienation subscales showed an association between alienation and risk. These results are consistent with other studies about alienation which emphasizes that having good social relationships is associated with higher levels of wellbeing and quality of life and less involvement in risk behaviours by young peopleinfo:eu-repo/semantics/publishedVersio

    Antibacterial activity and mode of action of selected glucosinolate hydrolysis products against bacterial pathogens

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    Plants contain numerous components that are important sources of new bioactive molecules with antimicrobial properties. Isothiocyanates (ITCs) are plant secondary metabolites found in cruciferous vegetables that are arising as promising antimicrobial agents in food industry. The aim of this study was to assess the antibacterial activity of two isothiocyanates (ITCs), allylisothiocyanate (AITC) and 2-phenylethylisothiocyanate (PEITC) against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Listeria monocytogenes. The antibacterial mode of action was also characterized by the assessment of different physiological indices: membrane integrity, intracellular potassium release, physicochemical surface properties and surface charge. The minimum inhibitory concentration (MIC) of AITC and PEITC was 100 g/mL for all bacteria. The minimum bactericidal concentration (MBC) of the ITCs was at least 10 times higher than the MIC. Both AITC and PEITC changed the membrane properties of the bacteria decreasing their surface charge and compromising the integrity of the cytoplasmatic membrane with consequent potassium leakage and propidium iodide uptake. The surface hydrophobicity was also non-specifically altered (E. coli and L. monocytogenes become less hydrophilic; P. aeruginosa and S. aureus become more hydrophilic). This study shows that AITC and PEITC have strong antimicrobial potential against the bacteria tested, through the disruption of the bacterial cell membranes. Moreover, phytochemicals are highlighted as a valuable sustainable source of new bioactive products.This work was supported by the Operational Programme for Competitiveness Factors - COMPETE and by the Portuguese Foundation for Science and Technology through Project Phytodisinfectants - PTDC/DTP-SAP/1078/2012 (COMPETE: FCOMP-01-0124-FEDER-028765), the PhD grant awarded to Ana Abreu (SFRH/BD/84393/2012), and the post-doctoral grants awarded to Anabela Borges (SFRH/BPD/98684/2013) and Lucia C. Simoes (SFRH/BPD/81982/2011). Also, this work was undertaken as part of the European Research Project SUSCLEAN (Contract no FP7-KBBE-2011-5, project number: 287514) and the COST Action FA1202. The authors are solely responsible for this work. It does not represent the opinion of the European Community, and the Community is not responsible for any use that might be made of data appearing herein

    Do clinical and psychosocial factors affect health-related quality of life in adolescents with chronic diseases?

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    Copyright © 2006 - 2018 The Canadian Center of Science and Education. All Rights Reserved. Copyright for this article is retained by the author(s), with first publication rights granted to the journal. This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/).Living with a chronic disease in adolescence can have an impact on the perception of Health-related Quality of Life (HRQoL). Facing the increasing relevance of psychosocial dimensions and also considering the interaction with clinical variables, this study aimed to measure the impact of clinical and psychosocial factors (separated and combined) on adolescent’s reported HRQoL. A cross-sectional study was conducted in a clinical population of 135 adolescents with chronic diseases (n=70 boys), average age: 14±1.5 years old. Through a self-reported questionnaire, HRQoL (KIDSCREEN-10), socio-demographic, clinical variables (diagnostic; time of diagnosis; self-perceived pain; disease severity proxy; disease-related medication intake/use of special equipment), and psychosocial variables (psychosomatic health; resilience; self-regulation; social support) were assessed. Separately, clinical and psychosocial variables showed a significant impact in HRQoL, 27.9% and 62.4%, respectively. Once combined, the previously identified variables had a significant impact (64.2%), but a different contribution from clinical and psychosocial variables was revealed: when first entering the clinical variables (model 1) the variance only reaches 30%, and much more from psychosocial variables seems to explain the total (64.2%); inversely, when first integrating psychosocial variables (model 2), the clinical ones added a small significance to the model (0.6%). The present study underlined the association of clinical (“disease-related”) and psychosocial (“non-disease-related”) factors on HRQoL. Furthermore, it reinforced the need to focus more on psychosocial dimensions, highlighted the potential role of psychosomatic health, resilience, self-regulation and social support. It can be suggested that the identification of impaired psychosocial domains may help professionals to better plan, and achieve effective interventions of psychosocial care.Santos, T. was supported by a PhD grant from the Portuguese Foundation for Science and Technology (FCT) (Grant Number: reference SFRH/BD/82066/2011). The William James Center for Research, ISPA - Instituto Universitário is supported by a grant from the Portuguese Foundation for Science and Technology (FCT) (Grant Number: UID/PSI/04810/2013). The present study is grateful to all youngsters and parents who participated in this project, also to the health care professionals who collaborated, as well as to the Pediatrics Department of Hospital Santa Maria, CAML (Lisbon Academic Medical Center) for their assistance in this investigation. The authors are also grateful to Prof. Paula Ravasco, MD, PhD (University Hospital of Santa Maria, Portugal) for her assistance in proof-reading and revising the document.info:eu-repo/semantics/publishedVersio

    The four hexamerin genes in the honey bee: structure, molecular evolution and function deduced from expression patterns in queens, workers and drones

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    Background: Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results: The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110) diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs) revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp), a target of juvenile hormone (JH). The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste-and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions: Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body and gonads suggest that, in addition to their primary role in supplying amino acids for metamorphosis, hexamerins serve as storage proteins for gonad development, egg production, and to support foraging activity. A phylogenetic analysis including the four deduced hexamerins and related proteins revealed a complex pattern of evolution, with independent radiation in insect orders.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[05/03926-5; 08/00541-3

    Critical review on biofilm methods

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    Biofilms are widespread in nature and constitute an important strategy implemented by microorganisms to survive in sometimes harsh environmental conditions. They can be beneficial or have a negative impact particularly when formed in industrial settings or on medical devices. As such, research into the formation and elimination of biofilms is important for many disciplines. Several new methodologies have been recently developed for, or adapted to, biofilm studies that have contributed to deeper knowledge on biofilm physiology, structure and composition. In this review, traditional and cutting-edge methods to study biofilm biomass, viability, structure, composition and physiology are addressed. Moreover, as there is a lack of consensus among the diversity of techniques used to grow and study biofilms. This review intends to remedy this, by giving a critical perspective, highlighting the advantages and limitations of several methods. Accordingly, this review aims at helping scientists in finding the most appropriate and up-to-date methods to study their biofilms.The authors would like to acknowledge the support from the EU COST Action BacFoodNet FA1202

    Gene expression clines reveal local adaptation and associated trade-offs at a continental scale

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    Local adaptation, where fitness in one environment comes at a cost in another, should lead to spatial variation in trade-offs between life history traits and may be critical for population persistence. Recent studies have sought genomic signals of local adaptation, but often have been limited to laboratory populations representing two environmentally different locations of a species' distribution. We measured gene expression, as a proxy for fitness, in males of Drosophila subobscura, occupying a 20° latitudinal and 11 °C thermal range. Uniquely, we sampled six populations and studied both common garden and semi-natural responses to identify signals of local adaptation. We found contrasting patterns of investment: transcripts with expression positively correlated to latitude were enriched for metabolic processes, expressed across all tissues whereas negatively correlated transcripts were enriched for reproductive processes, expressed primarily in testes. When using only the end populations, to compare our results to previous studies, we found that locally adaptive patterns were obscured. While phenotypic trade-offs between metabolic and reproductive functions across widespread species are well-known, our results identify underlying genetic and tissue responses at a continental scale that may be responsible for this. This may contribute to understanding population persistence under environmental change

    Sleep and sex sleep in adolescence : sex matters?

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    © 2019 All rights reservedObjective: Sleep is of upmost importance for everybody and especially for adolescents who face life and leisure challenges that may impair their sleep. This study aimed to verify if girls are at a higher risk to present sleep problems and if associations of a sleep perception are different between sexes even when accounting for biological maturation. Methods: Data is from the HBSC Portuguese survey 2014, all variables were self-reported. Participants were 3869 adolescents (2057 girls), mean age 14.8 years. Participants’ socio-demographic characteristics included sex, age, school grade, father and mother education; besides participants were inquired about sleep duration and characteristics of their sleep quality. Results: Sleep deprivation was reported by 13.1% of the adolescents (girls 14.3%, boys 11.7%, p<0.05). The most prevalent characteristics of poor sleep quality were waking up tired (50.8%) and difficulties falling asleep (19.5%), for both girls presented higher prevalence than boys. Overall, girls presented a poorer sleep health with low quality and quantity of sleep. Furthermore, associations of an enough and good sleep were different between boys and girls, even when controlling for the impact of delayed pubertal maturity. Discussion: Together with screen time, substance use, poorer nutrition, sedentary behaviours and abuse of screen time, sleep is an issue that must be addressed by professionals, families and public policies with impact in family life and family routines. Modelling a health education in schools should include the sleep topic. In addition, yes, sex matters and must be included on board.info:eu-repo/semantics/publishedVersio
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