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Saliency-driven system models for cell analysis with deep learning.
Background and objectivesSaliency refers to the visual perception quality that makes objects in a scene to stand out from others and attract attention. While computational saliency models can simulate the expert's visual attention, there is little evidence about how these models perform when used to predict the cytopathologist's eye fixations. Saliency models may be the key to instrumenting fast object detection on large Pap smear slides under real noisy conditions, artifacts, and cell occlusions. This paper describes how our computational schemes retrieve regions of interest (ROI) of clinical relevance using visual attention models. We also compare the performance of different computed saliency models as part of cell screening tasks, aiming to design a computer-aided diagnosis systems that supports cytopathologists.MethodWe record eye fixation maps from cytopathologists at work, and compare with 13 different saliency prediction algorithms, including deep learning. We develop cell-specific convolutional neural networks (CNN) to investigate the impact of bottom-up and top-down factors on saliency prediction from real routine exams. By combining the eye tracking data from pathologists with computed saliency models, we assess algorithms reliability in identifying clinically relevant cells.ResultsThe proposed cell-specific CNN model outperforms all other saliency prediction methods, particularly regarding the number of false positives. Our algorithm also detects the most clinically relevant cells, which are among the three top salient regions, with accuracy above 98% for all diseases, except carcinoma (87%). Bottom-up methods performed satisfactorily, with saliency maps that enabled ROI detection above 75% for carcinoma and 86% for other pathologies.ConclusionsROIs extraction using our saliency prediction methods enabled ranking the most relevant clinical areas within the image, a viable data reduction strategy to guide automatic analyses of Pap smear slides. Top-down factors for saliency prediction on cell images increases the accuracy of the estimated maps while bottom-up algorithms proved to be useful for predicting the cytopathologist's eye fixations depending on parameters, such as the number of false positive and negative. Our contributions are: comparison among 13 state-of-the-art saliency models to cytopathologists' visual attention and deliver a method that the associate the most conspicuous regions to clinically relevant cells
CP properties of symmetry-constrained two-Higgs-doublet models
The two-Higgs-doublet model can be constrained by imposing Higgs-family
symmetries and/or generalized CP symmetries. It is known that there are only
six independent classes of such symmetry-constrained models. We study the CP
properties of all cases in the bilinear formalism. An exact symmetry implies CP
conservation. We show that soft breaking of the symmetry can lead to
spontaneous CP violation (CPV) in three of the classes.Comment: 14 pages, 2 tables, revised version adapted to the journal
publicatio
Doença de Kawasaki: casuÃstica do Hospital Fernando da Fonseca
Introdução: A doença de Kawasaki (DK) é a
doença cardÃaca adquirida mais importante
da infância, em paÃses desenvolvidos. Vinte
por cento das crianças não tratadas
desenvolvem doença das coronárias, sendo as
complicações a nÃvel cardiovascular que
determinam a morbilidade e mortalidade da
doença.
Objectivo: Avaliar a epidemiologia, clÃnica e alterações laboratoriais e ecocardiográficas dos casos de DK diagnosticados no H. Fernando Fonseca e identificar os eventuais factores que possam influenciar o prognóstico
da doença. População e Métodos: Estudo retrospectivo, Junho 1996 a Dezembro de 2003, das crianças internadas no Hospital Fernando Fonseca com Doença Kawasaki. O
diagnóstico baseou-se na presença de febre
associada a 4 dos 5 critérios clássicos ou 3
deles em associação com aneurismas coronários. Analisaram-se parâmetros
demográficos, clÃnica, exames
complementares, terapêutica e evolução. A
análise estatÃstica foi realizada em SPSS,
utilizando os testes de Mann-whitney e Teste
Exacto de Fisher.
Resultados: Registaram-se 23 crianças com
DK. A incidência foi de 8,2 por 100 000
crianças < 5 anos. A idade variou entre os 6
meses e os 5 anos (mediana - 20 meses) Vinte
e uma (91 %) tinham < 5 anos, dos quais 13
tinham < 2 anos. Houve um predomÃnio do
sexo masculino (74 %) e da raça caucasiana
(83 %). Nove casos residiam na mesma área
geográfica. Foi documentada patologia
infecciosa concomitante em 10 (43%)crianças (Parvovirus, Chlamydia pneumoniae, VÃrus sincicial respiratório, Enterovirus e
Herpes vÃrus 6). Vinte crianças preenchiam
os critérios de DK clássica. Em 22 crianças
foi administrada terapêutica combinada com
aspirina e imunoglobulina endovenosa, em
média foi administrada ao 7.º dia de doença.
Sete (30 %) crianças apresentaram
envolvimento das artérias coronárias. A idade inferior a 2 anos foi significativa para a lesão coronária. O tempo médio de seguimento foi de 16 meses. Não se registou mortalidade e actualmente apenas uma criança mantém aneurisma.
Conclusões: O risco de lesões cardÃacas
associou-se à idade inferior a 2 anos, como
descrito em outras séries. A origem geográfica em comum e a presença de diversos agentes infecciosos, pode indiciar, a importância da causa infecciosa como desencadeadora do processo
Barriers to participation in a placebo-surgical trial for lumbar spinal stenosis
© 2019 Background: Placebo-controlled trials are an important tool when assessing the efficacy of spinal surgical procedures. The most common spinal surgical procedure in older adults is decompression for lumbar spinal stenosis. Before conducting a placebo-surgical trial on decompression surgery, an investigation of patients’ willingness to participate in a placebo-controlled trial of decompression surgery and barriers to participation were explored. Materials: An online survey. Methods: Descriptive analyses of demographic and clinical data, and participants' willingness to participate in a placebo-surgical trial. Logistic regression was used to examine potential predictors of willingness to participate. Two independent researchers performed a coded framework analysis of patients’ barriers to participation. Results: 68 patients were invited and 63 participants completed the survey (91.3% response, mean (SD) age 69.5 (10.9) years, 52% females), 71% suffered from moderate to very severe pain. Ten participants (15.9%) were willing to participate in a placebo-controlled trial. Being married was associated with decreased odds of participating (OR: 0.2; 95% CI, 0.05 to 0.8; P = 0.03), while the main barriers were a lack of information about the procedure, reassurance of a positive outcome with participation, and concerns about the risks and benefits of placebo surgery. Conclusions: A minority of patients with lumbar spinal stenosis were willing to participate in a placebo-controlled trial of surgery. The identified barriers indicate that educating eligible patients about: the need for placebo-surgical trials, the personal risks and benefits of participation, and the importance and potential benefits of placebo trials to others, may be crucial to ensure adequate recruitment into the placebo-controlled surgical trial. Conclusions should be read cautiously however, given the small sample size present in this study
Immunomodulatory properties of Musa paradisiaca L. inflorescence in Combined Allergic Rhinitis and Asthma Syndrome (CARAS) model towards NFκB pathway inhibition
Musa paradisiaca L. (Musaceae), a tropical plant named banana is used as food and as medicine in Brazil. Banana inflorescence, popularly known as mangará, presents several biological activities including anti-inflammatory effects. Here, we demonstrated the immunomodulatory activity of banana inflorescence extract (HEM) on a mice model of combined allergic rhinitis and asthma syndrome (CARAS) and in human macrophages. The HEM inhibited the eosinophil migration, production of cytokines as IL-4, IL-5, IL-13, and IL-17A dependent on IFN-¿ production in the airway. The mechanism of the extract was, in part, by the NF-¿B signaling pathway inhibition. Besides, the HEM decreased expression of the CD86 and HLA-DR receptors on human M1 macrophages independently of M2 modulation. Therefore, we infer that the inflorescence, a disposable material from the banana crops, has anti-allergic property in the CARAS model and modulates the human macrophages, characterizing it as biologically important material for the production of phytomedicine.This work was supported by Brazilian agencies National Council for Scientific and Technological Development (CNPq), Coordination for the Improvement of Higher Education Personnel (CAPES), Institute for Research and Innovation in Health (I3S) and National Institute of Biomedical Engineering (INEB). The authors would like to thank Serviço de Imunohemoterapia of Centro Hospitalar Universitário de São João (CHUSJ), Porto, Portugal, for kindly donating Buffy Coats. The authors are also grateful for the valuable assistance provided by agencies, institutes and collaborators.
This work was supported by Brazilian agencies National Council for Scientific and Technological Development (CNPq), Coordination for the Improvement of Higher Education Personnel (CAPES), Institute for Research and Innovation in Health (I3S) and National Institute of Biomedical Engineering (INEB). The authors would like to thank Serviço de Imunohemoterapia of Centro Hospitalar Universitário de São João (CHUSJ), Porto, Portugal, for kindly donating Buffy Coats. The authors are also grateful for the valuable assistance provided by agencies, institutes and collaborators
Endothelial Progenitor Cells influence acute and subacute stroke hemodynamics
BACKGROUND:
Endothelial Progenitor Cells (EPCs) are a circulating stem cell population with in vivo capacity of promoting angiogenesis after ischemic events. Despite the promising preclinical data, their potential integration with reperfusion therapies and hemodynamic evolution of stroke patients is still unknown. Our aim was to determine the association of EPCs with acute, subacute and chronic hemodynamic features.
METHODS:
In this prospective study, we included consecutive patients with ages between 18 and 80years and non-lacunar ischemic stroke within the territory of a middle cerebral artery. All patients were subject to hemodynamic evaluation by ultrasound at baseline, seven days and three months. We quantified cerebral blood flow (CBF) and assessed early recanalization and collateral flow. Hemorrhagic transformation was graded in Magnetic Resonance imaging performed at seven days. EPCs were isolated from peripheral venous blood collected in the first 24h and seven days, counted and submitted to functional in vitro tests.
RESULTS:
We included 45 patients with a median age of 70±10years. The angiogenic and migratory capacities of EPCs were associated with increased collateral flow in the acute stage and day seven CBF, without statistically significant associations with recanalization nor haemorrhagic transformation. The number of EPCs was not associated with any hemodynamic variable.
CONCLUSIONS:
The functional properties of EPCs are associated with acute and subacute stroke hemodynamics, with no effect on haemorrhagic transformation.info:eu-repo/semantics/publishedVersio
Alimentação e nutrição do lactente
Os autores apresentam os resultados de uma ampla revisão bibliográfica do conhecimento e práticas relativas à alimentação e nutrição do lactente, tendo por base a evidência cientÃfica existente e as recomendações dos principais comités de nutrição pediátrica.É sublinhada a importância do aleitamento materno, se possÃvel de modo exclusivo durante os primeiros 6 meses de vida e é referida a evolução da maturação fisiológica e das preferências alimentares associadas à diversificação alimentar.São apresentados os principais dados relativos ao teor dos alimentos em nutrientes, à idade de inÃcio da diversifica-ção e ao modo de progressão da alimentação ao longo do primeiro ano de vida. São feitas considerações especÃficas em relação a grupos especiais de nutrientes, como é o caso dos micronutrientes, bem como no tocante a componentes com interesse para a saúde da criança, cada vez mais usados na alimentação do lactente, como é o caso dos pré e probióticos.As potenciais repercussões para a saúde da alimentação são também referidas, em particular no tocante à prevenção de alergias, risco cardiovascular e doença celÃaca. Finalmente são abordados alguns dos aspectos mais relevantes para a alimentação e saúde do lactente ligados a dietas especiais nomeadamente vegetarianas e macrobióticas
Constraining parameter space in type-II two-Higgs doublet model in light of a 126 GeV Higgs boson
We explore the implications of a 126 GeV Higgs boson indicated by the recent
LHC results for two-Higgs doublet model (2HDM). Identifying the 126 GeV Higgs
boson as either the lighter or heavier of CP even neutral Higgs bosons in 2HDM,
we examine how the masses of Higgs fields and mixing parameters can be
constrained by the theoretical conditions and experimental constraints. The
theoretical conditions taken into account are the vacuum stability,
perturbativity and unitarity required to be satisfied up to a cut-off scale. We
also show how bounds on the masses of Higgs bosons and mixing parameters depend
on the cut-off scale. In addition, we investigate whether the allowed regions
of parameter space can accommodate particularly the enhanced di-photon signals,
ZZ* and WW* decay modes of the Higgs boson, and examine the prediction of the
signal strength of Z{\gamma} decay mode for the allowed regions of the
parameter space.Comment: To be published in JHEP, 20 pages, 11 figures, Figures and results
are updated for the recent LHC result
Universality of Strength of Yukawa Couplings, Quark Singlets and Strength of CP Violation
We analyse the strength of CP violation in an extension of the standard model
with an extra vector-like singlet quark, in the framework of the
hypothesis of universality of strength of Yukawa couplings connecting standard
quarks. We show that the correct pattern of quark masses and mixing can be
obtained, including the observed strength of CP violation.Comment: 9 pages, no figure
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