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- Update of the Portuguese Familial Hypercholesterolaemia StudyPublication . Medeiros, A.M.; Alves, A.C.; Francisco, V.; Bourbon, M.; Investigators of the Portuguese FH StudyThe main aim of the Portuguese Familial Hypercholesterolaemia Study is to identify the genetic cause of hypercholesterolaemia in individuals with a clinical diagnosis of Familial Hypercholesterolaemia (FH). A total of 1340 blood samples were collected from 482 index patients and 858 relatives with the collaboration of clinicians from several hospitals all over the country. The genetic diagnosis of FH in this study is based on the analyses of three genes: LDLR, APOB and PCSK9. In the last 10 years, the Portuguese FH Study identified a genetic defect in a total of 171 index patients, corresponding to an overall of 48% of the total received cases with clinical diagnosis of FH. Although the Simon Broome FH register criteria have been adapted to our study, 59 patients that did not fulfil all criteria were included in the study and a mutation causing disease was identified in 8 of these patients. In the LDLR gene were found 80 different mutations in 165 unrelated index patients: 159 heterozygous, 3 compounds heterozygous and 3 true homozygous. The APOB p.Arg3527Gln and the PCSK9 p.Asp374His mutation were not found in any of our patients since our last report, but a novel mutation in the APOB gene, predicted to cause a single amino acid substitution p.Tyr3560Cys, was found in one patient. The cascade screening in relatives of these 171 index patients allowed the identification and genetic characterization of a total of 404 FH patients in Portugal.
- Increased BDNF levels and NTRK2 gene association suggest a disruption of BDNF/TrkB signaling in autismPublication . Correia, C.T.; Coutinho, A.M.; Sequeira, A.F.; Sousa, I.G.; Lourenço Venda, L.; Almeida, J.P.; Abreu, R.L.; Lobo, C.; Miguel, T.S.; Conroy, J.; Cochrane, L.; Gallagher, L.; Gill, M.; Ennis, S.; Oliveira, G.G.; Vicente, A.M.The brain-derived neurotrophic factor (BDNF), a neurotrophin fundamental for brain development and function, has previously been implicated in autism. In this study, the levels of BDNF in platelet-rich plasma were compared between autistic and control children, and the role of two genetic factors that might regulate this neurotrophin and contribute to autism etiology, BDNF and NTRK2, was examined. We found that BDNF levels in autistic children (n = 146) were significantly higher (t = 6.82; P < 0.0001) than in control children (n = 50) and were positively correlated with platelet serotonin distribution (r = 0.22; P = 0.004). Heritability of BDNF was estimated at 30% and therefore candidate genes BDNF and NTRK2 were tested for association with BDNF level distribution in this sample, and with autism in 469 trio families. Genetic association analysis provided no evidence for BDNF or NTRK2 as major determinants of the abnormally increased BDNF levels in autistic children. A significant association with autism was uncovered for six single nucleotide polymorphisms (SNPs) [0.004 (Z((1df)) = 2.85) < P < 0.039 (Z((1df)) = 2.06)] and multiple haplotypes [5 × 10(-4) (χ((3df)) = 17.77) < P < 0.042 (χ((9df)) = 17.450)] in the NTRK2 gene. These results do not withstand correction for multiple comparisons, however, reflect a trend toward association that supports a role of NTRK2 as a susceptibility factor for the disorder. Genetic variation in the BDNF gene had no impact on autism risk. By substantiating the previously observed increase in BDNF levels in autistic children in a larger patient set, and suggesting a genetic association between NTRK2 and autism, this study integrates evidence from multiple levels supporting the hypothesis that alterations in BDNF/tyrosine kinase B (TrkB) signaling contribute to an increased vulnerability to autism.
- Molecular detection of hemoprotozoa and Rickettsia species in arthropods collected from wild animals in the Burgos Province, SpainPublication . Lledó, Lourdes; Giménez-Pardo, Consuelo; Domínguez-Peñafiel, Gerardo; Sousa, Rita; Gegúndez, Maria Isabep; Casado, Nieves; Criado, AngelLimited information on the presence of bacterial and hematozoan infections in parasitic arthropods from Spain is available. In an attempt to address this issue, the prevalence of Theileria, Babesia, Hepatozoon, and Rickettsia species was investigated by polymerase chain reaction plus sequencing. In a survey for zoonotic pathogens in ectoparasites, 42 wild animals (which included rodents, carnivores, Sciuridae, and Cervidae) were captured in Burgos (Spain). A total of 256 arthropods (including 107 ticks, 76 fleas, and 73 mites) were collected from these mammals. Molecular diagnostic results showed that (i) Rickettsia felis was found in fleas (two Ctenocephalides felis), (ii) Hepatozoon sp. infected some fleas (two Ctenophtalmus sp. and a DNA pool of Ceratophyllus sciurorum) and Acari (one Neotrombicula sp.), and (iii) Theileria annae was found in Ixodes ricinus and I. hexagonus (each a single infected specimen). All microorganisms and parasites were genetically identical to pathogens already described in Spain or elsewhere. Infected arthropods were recovered from beech marten, bank vole, squirrel, wood mouse, and red fox. Our findings emphasize the potential risk for transmission of rickettsias to humans (namely, R. felis) in Burgos, since C. felis is capable to seek out humans for feeding. No hemoprotozoa with proven significance as human pathogens were found in the survey. However, finding T. annae in ticks recovered from wild canids suggests possible links of sylvatic and domestic cycles for some Piroplasmida.
- A Gripe em Portugal nas épocas 2008/2009 e 2009/2010 - Relatório do Programa Nacional de Vigilância da GripePublication . Guiomar, Raquel; Nunes, Baltazar; Gonçalves, PauloApesar de um contexto epidemiológico que se revelava inicialmente potencialmente diferente, a actividade gripal na época de Gripe de 2009/2010, considerada desde a detecção do primeiro caso, em Portugal, associado à infecção com o novo subtipo de vírus Influenza A(H1N1)2009, revelou-se semelhante ao Inverno de 2008/2009 relativamente à intensidade e dispersão. Na época 2008/2009 observou-se uma maior incidência da doença nos grupos etários de maior idade. Os vírus detectados foram predominantemente influenza A(H3N2) embora também tenham sido detectados alguns vírus influenza B e influenza A(H1N1) sazonais. Na época 2009/2010, observou-se a circulação de um vírus parcialmente novo para a população Humana - o influenza A(H1N1) pandémico. A incidência da doença foi, neste caso, superior nos grupos etários mais jovens, compatível com a existência de uma imunidade residual na população mais idosa.
- Air conditioning and intrahospital mortality during the 2003 heatwave in Portugal: evidence of a protective effectPublication . Nunes, Baltazar; Paixão, Eleonora; Dias, Carlos Matias; Nogueira, Paulo; Falcão, José MarinhoObjectives - The objective of the study was to analyse the association between the presence of air conditioning in hospital wards and the intrahospital mortality during the 2003 heatwave, in mainland Portugal. Methods Historical cohort study design including all patients aged 45 or more who were hospitalised in the 7 days before the heatwave. The outcome was survival during the 18 days the heatwave lasted and during the 2 days after the end of the heatwave. A comparison group was also selected in four analogous periods without any heatwave event during January to May 2003. Data were obtained from the 2003 hospital discharges database. Air conditioning presence in hospital wards was determined using a survey sent to hospital administrations. A Cox-regression model was used to estimate the confounder-adjusted HR of death, during the heatwave and the comparison period, in patients in wards with air conditioning (AC+) versus patients in wards without air conditioning (AC−). Results 41 hospitals of mainland Portugal (49% of all hospitals in mainland Portugal) participated, and 2093 patients were enrolled. The overall confounder-adjusted HR of death in AC+ patients versus AC− patients was 0.60 (95% CI 0.37 to 0.97) for the heatwave period and 1.05 (95% CI 0.84 to 1.32) for the comparison group. Conclusions The study found strong evidence that, during the August 2003 heatwave, the presence of air conditioning in hospital wards was associated with an increased survival of patients admitted before the beginning of the climate event. The reduction of the risk of dying is estimated to be 40% (95% CI 3% to 63%).
- Adaptive evolution of the Chlamydia trachomatis dominant antigen reveals distinct evolutionary scenarios for B- and T-cell epitopes: worldwide surveyPublication . Nunes, A.; Nogueira, P.J.; Borrego, M.J.; Gomes, João PauloBackground: Chlamydia trachomatis is one of the most disseminated human pathogens, for which no vaccine is available yet. Understanding the impact of the host pressure on pathogen antigens is crucial, but so far it was only assessed for highly-restricted geographic areas. We aimed to evaluate the evolutionary picture of the chlamydial key antigen (MOMP), which is one of the leading multi-subunit vaccine candidates, in a worldwide basis. Methodology/Principal Findings: Using genetics, molecular evolution methods and mathematical modelling, we analyzed all MOMP sequences reported worldwide, composed by 5026 strains from 33 geographic regions of five continents. Overall, 35.9% of variants were detected. The evolutionary pattern of MOMP amino acid gains/losses was found to differ from the remaining chromosome, reflecting the demanding constraints of this porin, adhesin and dominant antigen. Amino acid changes were 4.3-fold more frequent in host-interacting domains (P,10212), specifically within B-cell epitopes (P,1025), where 25% of them are at fixation (P,1025). According to the typical pathogen-host arms race, this rampant B-cell antigenic variation likely represents neutralization escape mutants, as some mutations were previously shown to abrogate neutralization of chlamydial infectivity in vitro. In contrast, T-cell clusters of diverse HLA specificities are under purifying selection, suggesting a strategy that may lead to immune subversion. Moreover, several silent mutations are at fixation, generating preferential codons that may influence expression, and may also reflect recombination-derived ‘hitchhikingeffect’ from favourable nonsilent changes. Interestingly, the most prevalent C. trachomatis genotypes, E and F, showed a mutation rate 22.3-fold lower than that of the remainder (P,10220), suggesting more fitted antigenic profiles. Conclusions/Significance: Globally, the adaptive evolution of the C. trachomatis dominant antigen is likely driven by its complex pathogenesis-related function and reflects distinct evolutionary antigenic scenarios that may benefit the pathogen, and thus should be taking into account in the development of a MOMP-based vaccine.
- A genome-wide scan for common alleles affecting risk for autismPublication . Anney, R.; Klei, L.; Pinto, D.; Regan, R.; Conroy, J.; Magalhaes, T.R.; Correia, C.; Abrahams, B.S.; Sykes, N.; Pagnamenta, A.T.; Almeida, J.; Bacchelli, E.; Bailey, A.J.; Baird, G.; Battaglia, A.; Berney, T.; Bolshakova, N.; Bölte, S.; Bolton, P.F.; Bourgeron, T.; Brennan, S.; Brian, J.; Carson, A.R.; Casallo, G.; Casey, J.; Chu, S.H.; Cochrane, L.; Corsello, C.; Crawford, E.L.; Crossett, A.; Dawson, G.; de Jonge, M.; Delorme, R.; Drmic, I.; Duketis, E.; Duque, F.; Estes, A.; Farrar, P.; Fernandez, B.A.; Folstein, S.E.; Fombonne, E.; Freitag, C.M.; Gilbert, J.; Gillberg, C.; Glessner, J.T.; Goldberg, J.; Green, J.; Guter, S.J.; Hakonarson, H.; Heron, E.A.; Hill, M.; Holt, R.; Howe, J.L.; Hughes, G.; Hus, V.; Igliozzi, R.; Kim, C.; Klauck, S.M.; Kolevzon, A.; Korvatska, O.; Kustanovich, V.; Lajonchere, C.M.; Lamb, J.A.; Laskawiec, M.; Leboyer, M.; Le Couteur, A.; Leventhal, B.L.; Lionel, A.C.; Liu, X.Q.; Lord, C.; Lotspeich, L.; Lund, S.C.; Maestrini, E.; Mahoney, W.; Mantoulan, C.; Marshall, C.R.; McConachie, H.; McDougle, C.J.; McGrath, J.; McMahon, W.M.; Melhem, N.M.; Merikangas, A.; Migita, O.; Minshew, N.J.; Mirza, G.K.; Munson, J.; Nelson, S.F.; Noakes, C.; Noor, A.; Nygren, G.; Oliveira, G.; Papanikolaou, K.; Parr, J.R.; Parrini, B.; Paton, T.; Pickles, A.; Piven, J.; Posey, D.J.; Poustka, A.; Poustka, F.; Prasad, A.; Ragoussis, J.; Renshaw, K.; Rickaby, J.; Roberts, W.; Roeder, K.; Roge, B.; Rutter, M.L.; Bierut, L.J.; Rice, J.P.; Salt, J.; Sansom, K.; Sato, D.; Segurado, R.; Senman, L.; Shah, N.; Sheffield, V.C.; Soorya, L.; Sousa, I.; Stoppioni, V.; Strawbridge, C.; Tancredi, R.; Tansey, K.; Thiruvahindrapduram, B.; Thompson, A.P.; Thomson, S.; Tryfon, A.; Tsiantis, J.; Van Engeland, H.; Vincent, J.B.; Volkmar, F.; Wallace, S.; Wang, K.; Wang, Z.; Wassink, T.H.; Wing, K.; Wittemeyer, K.; Wood, S.; Yaspan, B.L.; Zurawiecki, D.; Zwaigenbaum, L.; Betancur, C.; Buxbaum, J.D.; Cantor, R.M.; Cook, E.H.; Coon, H.; Cuccaro, M.L.; Gallagher, L.; Geschwind, D.H.; Gill, M.; Haines, J.L.; Miller, J.; Monaco, A.P.; Nurnberger Jr, J.I.; Paterson, A.D.; Pericak-Vance, M.A.; Schellenberg, G.D.; Scherer, S.W.; Sutcliffe, J.S.; Szatmari, P.; Vicente, A.M.; Vieland, V.J.; Wijsman, E.M.; Devlin, B.; Ennis, S.; Hallmayer, J.Although autism spectrum disorders (ASDs) have a substantial genetic basis, most of the known genetic risk has been traced to rare variants, principally copy number variants (CNVs). To identify common risk variation, the Autism Genome Project (AGP) Consortium genotyped 1558 rigorously defined ASD families for 1 million single-nucleotide polymorphisms (SNPs) and analyzed these SNP genotypes for association with ASD. In one of four primary association analyses, the association signal for marker rs4141463, located within MACROD2, crossed the genome-wide association significance threshold of P < 5 × 10(-8). When a smaller replication sample was analyzed, the risk allele at rs4141463 was again over-transmitted; yet, consistent with the winner's curse, its effect size in the replication sample was much smaller; and, for the combined samples, the association signal barely fell below the P < 5 × 10(-8) threshold. Exploratory analyses of phenotypic subtypes yielded no significant associations after correction for multiple testing. They did, however, yield strong signals within several genes, KIAA0564, PLD5, POU6F2, ST8SIA2 and TAF1C.
- A study protocol to evaluate the relationship between outdoor air pollution and pregnancy outcomesPublication . Ribeiro, M.C.; Pereira, M.J.; Soares, A.; Branquinho, C.; Augusto, S.; Llop, E.; Fonseca, S.; Nave, J.G.; Tavares, A.B.; Dias, Carlos Matias; Silva, A.; Selemane, I.; De Toro, J.; Santos, M.J.; Santos, F.Background - The present study protocol is designed to assess the relationship between outdoor air pollution and low birth weight and preterm births outcomes performing a semi-ecological analysis. Semi-ecological design studies are widely used to assess effects of air pollution in humans. In this type of analysis, health outcomes and covariates are measured in individuals and exposure assignments are usually based on air quality monitor stations. Therefore, estimating individual exposures are one of the major challenges when investigating these relationships with a semi-ecologic design. Methods/Design Semi-ecologic study consisting of a retrospective cohort study with ecologic assignment of exposure is applied. Health outcomes and covariates are collected at Primary Health Care Center. Data from pregnant registry, clinical record and specific questionnaire administered orally to the mothers of children born in period 2007-2010 in Portuguese Alentejo Litoral region, are collected by the research team. Outdoor air pollution data are collected with a lichen diversity biomonitoring program, and individual pregnancy exposures are assessed with spatial geostatistical simulation, which provides the basis for uncertainty analysis of individual exposures. Awareness of outdoor air pollution uncertainty will improve validity of individual exposures assignments for further statistical analysis with multivariate regression models. Discussion Exposure misclassification is an issue of concern in semi-ecological design. In this study, personal exposures are assigned to each pregnant using geocoded addresses data. A stochastic simulation method is applied to lichen diversity values index measured at biomonitoring survey locations, in order to assess spatial uncertainty of lichen diversity value index at each geocoded address. These methods assume a model for spatial autocorrelation of exposure and provide a distribution of exposures in each study location. We believe that variability of simulated exposure values at geocoded addresses will improve knowledge on variability of exposures, improving therefore validity of individual exposures to input in posterior statistical analysis.
- Quantification of endocrine disruptors and pesticides in water by gas chromatography-tandem mass spectrometry. Method validation using weighted linear regression schemesPublication . Mansilha, C.; Melo, A.; Rebelo, H.; Ferreira, I.M.; Pinho, O.; Domingues, V.; Pinho, C.; Gameiro, P.A multi-residue methodology based on a solid phase extraction followed by gas chromatography-tandem mass spectrometry was developed for trace analysis of 32 compounds in water matrices, including estrogens and several pesticides from different chemical families, some of them with endocrine disrupting properties. Matrix standard calibration solutions were prepared by adding known amounts of the analytes to a residue-free sample to compensate matrix-induced chromatographic response enhancement observed for certain pesticides. Validation was done mainly according to the International Conference on Harmonisation recommendations, as well as some European and American validation guidelines with specifications for pesticides analysis and/or GC-MS methodology. As the assumption of homoscedasticity was not met for analytical data, weighted least squares linear regression procedure was applied as a simple and effective way to counteract the greater influence of the greater concentrations on the fitted regression line, improving accuracy at the lower end of the calibration curve. The method was considered validated for 31 compounds after consistent evaluation of the key analytical parameters: specificity, linearity, limit of detection and quantification, range, precision, accuracy, extraction efficiency, stability and robustness.