74 research outputs found

    BIOMECHANICS OF THE PENALTY STROKE IN ROLLER HOCKEY

    Get PDF
    This paper describes a preliminary study on the biomechanics of the shot in roller hockey. This is a Portuguese sport having a most extensive prize list, where Portugal has been 15 times world champion, 20 European champions in senior male competition and won three world championships in senior female. Despite this impressive collection of titles, hockey continues to be the lesser studied sport, concretely regarding studies on biomechanics. The influence of sports equipment in the athlete’s performance and a detailed analysis of the main technical gestures had not motivated yet the researchers for detailed studies to enable their optimization. The purpose of this study was to characterize the mechanical properties of the stick (Aleu) and its influence on the shot power

    Influence of Aveiro Lagoon heavy metal contents in the adjacent continental shelf (Portugal)

    Get PDF
    A chemical analysis of Al, Ca, Fe, Mg, Cu, Pb, Zn, Cr, Co, Ni and Cd was carried out in 22 surface sediment samples of the continental shelf and upper slope between Espinho and Aveiro (Portugal). To reduce the disturbing effects of grain size, all samples were size-normalized by wet sieving (< 63 mu m). The fine fraction was digested with concentrated acids and analyzed by flame atomic absorption spectrometry. The Al and heavy metal concentrations displayed a similar distribution pattern, decreasing seaward. Exceptions to this general pattern are Ca, Mg and Pb distributions. The Ca contents are related to carbonated biogenic particles that are very abundant in the outer shelf. Multivariate statistical analysis was applied to all data to assess the behaviour and sources of each element analyzed. The results from factor analysis showed that terrigenous supply (from Aveiro Lagoon flow, coastal erosion and littoral drift), grain size (clay) sorting and anthropogenic influences from Aveiro Lagoon are the major factors controlling spatial variations of chemical elements in the continental shelf between Espinho and Aveiro. Unusually high contents of Pb were found in the middle shelf off Furadouro, but we could not determine the possible source of this contamination.info:eu-repo/semantics/publishedVersio

    População residente de um hospital psiquiátrico: que saúde visual?

    Get PDF
    Introdução - Numa tentativa pioneira em Portugal de avaliar o estado da visão dos pacientes residentes de um Hospital Psiquiátrico, foi nosso objectivo identificar alterações visuais existentes nesta população, passíveis de comprometer o funcionamento do sistema visual e com repercussões negativas nas actividades da vida diária; caracterizar e corrigir ametropias; relacionar as patologias encontradas com a medicação e seleccionar! encaminhar os utentes para consulta de oftalmologia. Métodos - Foram examinados 254 pacientes residentes num Hospital Psiquiátrico de Lisboa, com idade compreendida entre os 25 e os 92 anos de idade, com diagnóstico no âmbito da saúde mental, capacidade de deslocação e alguma autonomia. Na recolha de dados foi utilizado o protocolo de observação do rastreio visual, tendo sido avaliados os seguintes parâmetros: Acuidade visual, Estudo refractivo; Função sensório-motora; Visão cromática; Segmento anterior; Tensão ocular. O rastreio foi composto por duas fases: uma primeira fase para identificação das alterações visuais, com 254 residentes e uma segunda fase, com 100 residentes, para correcção das ametropias diagnosticadas e prescrição óptica. Os resultados foram sujeitos a uma análise estatística descritiva e inferencial através do programa SPSS. Resultados - A maioria dos pacientes era do sexo masculino (64,2%), internados principalmente por esquizofrenia (47,24%) e medicados com antipsicóticos (82,8%) mas tomando também anti-parkinsónicos (62,3%) e ansiolíticos (52,4%). Apenas 20,87% da amostra tinha feito anteriormente um exame visual. Além de 33,86% de cataratas, em que 27,4% representam residentes entre os 20 e os 50 anos, encontraram-se acuidades visuais baixas. Para longe, 51% dos indivíduos apresentavam acuidade visual no intervalo entre contar dedos e os 6/10. No que concerne à acuidade visual para perto, os resultados obtidos demonstram que a maioria da população apresenta também baixa acuidade visual, entre os 1/10 e os 3/10, tanto para olho direito (25,59%), como para o olho esquerdo (26,38%). É de referir que esta baixa acuidade visual atinge um total de 27 indivíduos no intervalo dos 40 aos 59 anos. Foi ainda identificado um número expressivo de exoforias para perto (38,58%) e 7,15% de neuropatias glaucomatosas. Do estudo refractivo (2. Fase do rastreio visual), resultou a prescrição de 75 óculos, o que levou a uma melhoria significativa da acuidade visual, principalmente para perto: 50% da amostra que apresentava acuidade visual, no intervalo de percepção luminosa aos 6/10, passou a 3%, após correcção refractiva. No decurso do rastreio 5 residentes foram encaminhadas para o serviço de urgência por neuropatia glaucomatosa e melanoma da coróide. Apenas 5,5% teve alta e os restantes foram encaminhados para consulta de oftalmologia (34% com prioridade). Conclusões - Este rastreio permitiu além da correcção das ametropias diagnosticadas, encaminhar, os residentes com alterações visuais, para tratamento, possibilitando assim, que esta população use a sua visão da melhor maneira e potencializando um aumento da qualidade de vida destes pacientes

    Beyond the limits of oxygen: effects of hypoxia in a hormone-independent prostate cancer cell line

    Get PDF
    Prostate cancer (PCa) has a high incidence worldwide. One of the major causes of PCa resistance is intratumoral hypoxia. In solid tumors, hypoxia is strongly associated with malignant progression and resistance to therapy, which is an indicator of poor prognosis. The antiproliferative effect and induced death caused by doxorubicin, epirubicin, cisplatin, and flutamide in a hormone-independent PCa cell line will be evaluated. The hypoxia effect on drug resistance to these drugs, as well as cell proliferation and migration, will be also analyzed. All drugs induced an antiproliferative effect and also cell death in the cell line under study. Hypoxia made the cells more resistant to all drugs. Moreover, our results reveal that long time cell exposure to hypoxia decreases cellular proliferation and migration. Hypoxia can influence cellular resistance, proliferation, and migration. This study shows that hypoxia may be a key factor in the regulation of PCa.info:eu-repo/semantics/publishedVersio

    Genetic Variants Underlying Risk of Intracranial Aneurysms: Insights from a GWAS in Portugal

    Get PDF
    Subarachnoid hemorrhage (SAH) is a life-threatening event that most frequently leads to severe disability and death. Its most frequent cause is the rupture of a saccular intracranial aneurysm (IA), which is a blood vessel dilation caused by disease or weakening of the vessel wall. Although the genetic contribution to IA is well established, to date no single gene has been unequivocally identified as responsible for IA formation or rupture. We aimed to identify IA susceptibility genes in the Portuguese population through a pool-based multistage genome-wide association study. Replicate pools were allelotyped in triplicate in a discovery dataset (100 IA cases and 92 gender-matched controls) using the Affymetrix Human SNP Array 6.0. Top SNPs (absolute value of the relative allele score difference between cases and controls |RASdiff|≥13.0%) were selected for technical validation by individual genotyping in the discovery dataset. From the 101 SNPs successfully genotyped, 99 SNPs were nominally associated with IA. Replication of technically validated SNPs was conducted in an independent replication dataset (100 Portuguese IA cases and 407 controls). rs4667622 (between UBR3 and MYO3B), rs6599001 (between SCN11A and WDR48), rs3932338 (214 kilobases downstream of PRDM9), and rs10943471 (96 kilobases upstream of HTR1B) were associated with IA (unadjusted allelic chi-square tests) in the datasets tested (discovery: 6.84E-04≤P≤1.92E-02, replication: 2.66E-04≤P≤2.28E-02, and combined datasets: 6.05E-05≤P≤5.50E-04). Additionally, we confirmed the known association with IA of rs1333040 at the 9p21.3 genomic region, thus validating our dataset. These novel findings in the Portuguese population warrant further replication in additional independent studies, and provide additional candidates to more comprehensively understand IA etiopathogenesis.FCT grant: (CMUP-ERI/TPE/0028/2013), FCT fellowships and research contracts (SFRH/BPD/35737/2007, SFRH/BPD/70008/2010, SFRH/BD/43895/2008 and Ciência and Investigator- FCT contracts)

    Treatment with subcutaneous and transdermal fentanyl: Results from a population pharmacokinetic study in cancer patients

    Get PDF
    Purpose: Transdermal fentanyl is effective for the treatment of moderate to severe cancer-related pain but is unsuitable for fast titration. In this setting, continuous subcutaneous fentanyl may be used. As data on the pharmacokinetics of continuous subcutaneous fentanyl are lacking, we studied the pharmacokinetics of subcutaneous and transdermal fentanyl. Furthermore, we evaluated rotations from the subcutaneous to the transdermal route. Methods: Fifty-two patients treated with subcutaneous and/or transdermal fentanyl for moderate to severe cancer-related pain participated. A population pharmacokinetic model was developed and evaluated using non-linear mixed-effects modelling. For rotations from subcutaneous to transdermal fentanyl, a 1:1 dose conversion ratio was used while the subcutaneous infusion was continued for 12 h (with a 50 % tapering after 6 h). A 6-h scheme with 50 % tapering after 3 h was simulated using the final model. Results: A one-compartment model with first-order elimination and separate first-order absorption processes for each route adequately described the data. The estimated apparent clearance of fentanyl was 49.6 L/h; the absorption rate constant for subcutaneous and transdermal fentanyl was 0.0358 and 0.0135 h-1, respectively. Moderate to large inter-individual and inter-occasion variability was found. Around rotation from subcutaneous to transdermal fentanyl, measured and simulated plasma fentanyl concentrations rose and increasing side effects were observed. Conclusions: We describe the pharmacokinetics of subcutaneous and transdermal fentanyl in one patient cohort and report several findings that are relevant for clinical practice. Further research is warranted to study the optimal scheme for rotations from the subcutaneous to the transdermal route
    corecore