Influência de diferentes parâmetros na diminuição da actividade extra-miocárdica nos estudos Gated-SPECT

A imagem de perfusão do miocárdio por tomografia computorizada de emissão de fotão único (SPECT, do acrónimo inglês Single Photon Emission Computed Tomography) é um dos exames complementares de diagnóstico mais indicados na cardiologia clínica. Os dois agentes tecneciados mais utilizados são o 99mTc-tetrofosmina e o 99mTc-sestamibi. Estes permitem avaliar a distribuição do fluxo sanguíneo no músculo cardíaco. O mecanismo de fixação é idêntico nos dois radiofármacos (RF’s). São excretados, do organismo, a partir do sistema hepatobiliar para o duodeno e para o intestino. Assim, o RF está presente tanto no coração como nos órgãos adjacentes. O coração encontra-se localizado sobre o diafragma, logo acima do lobo esquerdo do fígado e nas proximidades do estômago. Deste modo, os fotões difusos provenientes desses órgãos podem interferir com a interpretação das imagens SPECT, principalmente na parede inferior do ventrículo esquerdo, traduzindo-se na redução da razão alvo-fundo e na qualidade da imagem. Deste modo, a sensibilidade e a especificidade da Cintigrafia de Perfusão do Miocárdio (CPM) diminuem. Têm sido descritos na literatura vários métodos e técnicas para minimizar o efeito da actividade extra-miocárdica, como: a aquisição de imagens mais tardias, a ingestão de líquidos ou alimentos ricos em lípidos. Outras técnicas apontam para a alteração do posicionamento do paciente durante a aquisição. Assim, o objectivo deste estudo é identificar o protocolo da CPM a nível nacional e avaliar a percentagem de repetições de exames provocadas pela interferência de actividade extra-miocárdica

Influence of different parameters on the decrease of extra-myocardial activity Gated-SPECT studies

Introdução – A cintigrafia de perfusão do miocárdio (CPM) é um dos exames complementares de diagnóstico mais indicados na patologia cardiovascular. A atividade extramiocárdica é um problema recorrente na aquisição e avaliação da imagem. Parâmetros como o radiofármaco (RF) administrado, o tipo de esforço, a ingestão de alimentos, o posicionamento e o processamento de imagem influenciam a atividade extramiocárdica na CPM. O objetivo deste estudo é identificar o protocolo da CPM a nível nacional e avaliar a percentagem de repetições das aquisições provocadas por este problema. Metodologia – Para a realização deste estudo, a população selecionada foram os Serviços de Medicina Nuclear (SMN) em Portugal Continental. Foram analisados 15 questionários, respondidos pelos Técnicos Coordenadores dos vários SMN. Foi realizada a associação do comportamento das variáveis, através da estatística descritiva e do Coeficiente de Correlação de Spearman. Resultados – A percentagem de repetições é menor com o uso da 99mTecnécio(Tc)-Tetrofosmina, aquisição de imagens tardias, ingestão de diversos alimentos (água, leite, sumo, pão com manteiga) e com a correção de atenuação. Conclusão – Os resultados obtidos demonstram que a maioria das soluções aplicadas nos SMN resultam numa diminuição das repetições.ABSTRACT: Introduction – Myocardial perfusion imaging (MPI) is one of the most indicated complementary diagnostic exams in cardiovascular disease. Extra myocardial activity is a recurrent problem in the acquisition and evaluation of functional image. Parameters like the radiotracer (RT), the stress protocol, the ingestion of different aliments; the positioning and imaging processing interfere in extra-myocardial activity in MPI. The aim of this study is to identify the protocol of MPI at the national level and assess the percentage of repetitions of acquisitions caused by this problem. Methodology – For this study, the population selected were the Nuclear Medicine Services (NMS) in Continental Portugal. Were analyzed 15 surveys answered by the Technical Coordinators of the various NMS. Association of behavior of the variables has been made using descriptive statistics and the Spearman Correlation Coefficient. Results – The percentage of repetitions decrease with 99mTechnetium (Tc)-Tetrofosmine, delayed imaging, eating (water, milk, juice, bread with butter) and with attenuation correction. Conclusion – The results achieved in this study demonstrate that the majority solutions in NMS produce a decrease of exam repetitions

The validity of the Violence Risk Scale (VRS) in a Portuguese sample of remand prisoners

This study aims to test the psychometric properties of the Violent Risk Scale (VRS) in a sample of Portuguese remand prisoners. A total of 133 subjects participated in the present study. We carried out a Confirmatory Factor Analysis (CFA) to test the originally proposed two factor structure. Results showed evidence to support the VRS's psychometric qualities.The CFA tested the two-factor structure and showed evidence of the goodness of fit of the original two-factor model. Also, our findings indicated acceptable internal consistency for both sub scales. The correlational analyses supported both convergent and discriminant validity of the VRS. Finally, this study also tested known-groups validity. The VRS score showed a satisfactory postdictive accuracy, which means that it is able to demonstrate distinctive scores for groups known to vary on the variables being measured. We consider this work represents an essential support for decision-makers to evaluate the appropriateness of different judicial measures.info:eu-repo/semantics/publishedVersio

Novel insights into population dynamics and lineage differentiation of the coffee leaf rust pathogen Hemileia vastatrix

Comunicação OralN/

Interaction of benzothienoquinolines with DNA and lipid membranes monitored by fluorescence

RICI4 - Book of AbstractsThis work was funded by FCT-Portugal through CFUM, CQ-UM, research project PTDC/QUI/81238/2006 (cofinanced by FEDER/COMPETE, FCOMP-01-0124-FEDER-007467). R.C.C. acknowledges FCT the post-doctoral grant (SFRH/BPD/68344/2010

Comprehensive assembly and analysis of the transcriptome of maritime pine developing embryos

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Versatility and exploratory psychometric properties of the Impulsive/Premeditated Aggression Scale (IPAS): A review

Aggression has different conceptualizations and can be behaviorally expressed in diverse ways. Designed to evaluate impulsive and premeditated forms of aggression, the Impulsive/Premeditated Aggression Scale (IPAS; Stanford et al., 2003) is a 30 item self-report questionnaire. The aim of the present study was to explore IPAS versatility in different psychological settings by reviewing and examining the exploratory psychometric prop- erties of the IPAS impulsive and premeditated subscales, across different samples and cultural backgrounds. Fifty-two articles including demographic or psychometric information (internal consistency, factor analysis, validity, reliability) were retrieved. It is suggested that the IPAS is reliable across different cultures, samples and scoring techniques. The two subscales (Impulsive and Premeditated) show acceptable internal consistency. Also, IPAS factors seem to be constant both in clinical and non-clinical samples. The IPAS appears to be a clinically useful instrument for differentiating between subtypes of aggressive behavior, to support risk assessment eva- luations, pretrial decisions and better treatment and rehabilitation strategies in offenders and clinical relevant samples.This work was supported by The Foundation for Science and Technology (Grant number SFRH/BD/76062/2011), and the Portuguese Ministry of Science, Technology and Higher Education through national funds and co-financed by FEDER and COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER007653) - Psychology Research Centre (UID/PSI/01662), awarded to the first author. The study was also supported by Grant SFRH/BPD/108602/2015 from the Portuguese Foundation for Science and Technology awarded to Andreia de Castro-Rodrigues

The potencial role of soil application of a tris (3-hydroxy-4-pyridinonate) iron (III) complex in iron deficiency chlorosis treatment

info:eu-repo/semantics/publishedVersio

Small RNA profiling in Pinus pinaster reveals the transcriptome of developing seeds and highlights differences between zygotic and somatic embryos

Regulation of seed development by small non-coding RNAs (sRNAs) is an important mechanism controlling a crucial phase of the life cycle of seed plants. In this work, sRNAs from seed tissues (zygotic embryos and megagametophytes) and from somatic embryos of Pinus pinaster were analysed to identify putative regulators of seed/embryo development in conifers. In total, sixteen sRNA libraries covering several developmental stages were sequenced. We show that embryos and megagametophytes express a large population of 21-nt sRNAs and that substantial amounts of 24-nt sRNAs were also detected, especially in somatic embryos. A total of 215 conserved miRNAs, one third of which are conifer-specific, and 212 high-confidence novel miRNAs were annotated. MIR159, MIR171 and MIR394 families were found in embryos, but were greatly reduced in megagametophytes. Other families, like MIR397 and MIR408, predominated in somatic embryos and megagametophytes, suggesting their expression in somatic embryos is associated with in vitro conditions. Analysis of the predicted miRNA targets suggests that miRNA functions are relevant in several processes including transporter activity at the cotyledon-forming stage, and sulfur metabolism across several developmental stages. An important resource for studying conifer embryogenesis is made available here, which may also provide insightful clues for improving clonal propagation via somatic embryogenesis.publishersversionpublishe

Reliability of manual segmentation of cornea, contact lens and tear film using a high-resolution OCT

In this study, we aimed to evaluate the intra/inter-session and intra/inter-observer variability of manual segmentation of thickness of the pre-lens tear film, contact lens (CL), post-lens tear film, epithelium, bowman’s layer, stroma and the whole cornea and CLs with a flat and a steep fit, using a commercial high-resolution spectral domain optical coherence tomographer (OCT). Two different observers obtained three repeated measures in two separate sessions. A high correlation was found between the values obtained by the two different observers, except for the thinner layers, epithelium, and Bowman’s layer. Inter-observer analysis showed a high consistency in the measurements obtained by both observers (r 2 ≥ 0.80; p < 0.001) for the thicker layers: CL, stroma, and total cornea. Intra-observer analysis of measurements obtained by each observer within the same session displayed no statistically significant differences between the three repeated measures for both observers (p > 0.05). The present results suggest that manual segmentation of anterior segment OCT images in CL wearers provides acceptable levels of repeatability between observers and between different sessions for the thinner layers, while presenting a high level of repeatability for the thicker layers.This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/UI607/2011. Supported in part by research grants to A. Cervino from the Universitat de Valencia (UV-AE-20070225), the "Jose Castillejo" Research Grant from the Spanish Ministry of Science and Technology (JC2008-00078) and the Spanish Network for Research in Optometry (SAF2008-01114-E)