20 research outputs found

    Isogeometric analysis for fluid shear stress in cancer cells

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    Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2018 do Instituto Politécnico de Lisboa. Código de referência IPL/2018/IGACFC_ISELThe microenvironment of the tumor is a key factor regulating tumor cell invasion and metastasis. The effects of physical factors in tumorigenesis is unclear. Shear stress, induced by liquid flow, plays a key role in proliferation, apoptosis, invasion, and metastasis of tumor cells. The mathematical models have the potential to elucidate the metastatic behavior of the cells’ membrane exposed to these microenvironment forces. Due to the shape configuration of the cancer cells, Non-uniform Rational B-splines (NURBS) lines are very adequate to define its geometric model. The Isogeometric Analysis allows a simplified transition of exact CAD models into the analysis avoiding the geometrical discontinuities of the traditional Galerkin traditional techniques. In this work, we use an isogeometric analysis to model the fluid-generated forces that tumor cells are exposed to in the vascular and tumor microenvironments, in the metastatic process. Using information provided by experimental tests in vitro, we present a suite of numerical experiments which indicate, for standard configurations, the metastatic behavior of cells exposed to such forces. The focus of this paper is strictly on geometrical sensitivities to the shear stress’ exhibition for the cell membrane, this being its innovation.info:eu-repo/semantics/publishedVersio

    Guidelines for the management and treatment of periodic fever syndromes Cryopyrin-associated periodic syndromes (cryopyrinopathies – CAPS)

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    AbstractObjectiveTo establish guidelines based on cientific evidences for the management of cryopyrin associated periodic syndromes.Description of the evidence collection methodThe Guideline was prepared from 4 clinical questions that were structured through PICO (Patient, Intervention or indicator, Comparison and Outcome), to search in key primary scientific information databases. After defining the potential studies to support the recommendations, these were graduated considering their strength of evidence and grade of recommendation.Results1215 articles were retrieved and evaluated by title and abstract; from these, 42 articles were selected to support the recommendations.Recommendations1. The diagnosis of CAPS is based on clinical history and clinical manifestations, and later confirmed by genetic study. CAPS may manifest itself in three phenotypes: FCAS (mild form), MWS (intermediate form) and CINCA (severe form). Neurological, ophthalmic, otorhinolaryngological and radiological assessments may be highly valuable in distinguishing between syndromes; 2. The genetic diagnosis with NLRP3 gene analysis must be conducted in suspected cases of CAPS, i.e., individuals presenting before 20 years of age, recurrent episodes of inflammation expressed by a mild fever and urticaria; 3. Laboratory abnormalities include leukocytosis and elevated serum levels of inflammatory proteins; and 4. Targeted therapies directed against interleukin-1 lead to rapid remission of symptoms in most patients. However, there are important limitations on the long-term safety. None of the three anti-IL-1β inhibitors prevents progression of bone lesions

    American College of Rheumatology Provisional Criteria for Clinically Relevant Improvement in Children and Adolescents With Childhood-Onset Systemic Lupus Erythematosus

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    10.1002/acr.23834ARTHRITIS CARE & RESEARCH715579-59

    Risk factors for the development of hospital-acquired pediatric venous thromboembolism-Dealing with potentially causal and confounding risk factors using a directed acyclic graph (DAG) analysis.

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    IntroductionHospital-acquired venous thromboembolism (HA-VTE) in children comprises multiple risk factors that should not be evaluated separately due to collinearity and multiple cause and effect relationships. This is one of the first case-control study of pediatric HA-VTE risk factors using a Directed Acyclic Graph (DAG) analysis.Material and methodsRetrospective, case-control study with 22 cases of objectively confirmed HA-VTE and 76 controls matched by age, sex, unit of admission, and period of hospitalization. Descriptive statistics were used to define distributions of continuous variables, frequencies, and proportions of categorical variables, comparing cases and controls. Due to many potential risk factors of HA-VTE, a directed acyclic graph (DAG) model was created to identify confounding, reduce bias, and increase precision on the analysis. The final model consisted of a DAG-informed conditional logistic regression.ResultsIn the initial conventional univariable model, the following variables were selected as potential risk factors for HA-VTE: length of stay (LOS, days), immobility, ICU admission in the last 30 days, LOS in ICU, infection, central venous catheter (CVC), number of CVCs placed, L-asparaginase, heart failure, liver failure, and nephrotic syndrome. The final model using the set of variables selected by DAG analysis revealed LOS (OR = 1.106, 95%CI = 1.021-1.198, p = 0.013), L-asparaginase (OR = 26.463, 95%CI = 1.609-435.342, p = 0.022), and nephrotic syndrome (OR = 29.127, 95%CI = 1.044-812.508, p = 0.004) as independent risk factors for HA-VTE.ConclusionThe DAG-based approach was useful to clarify the influence of confounders and multiple causalities of HA-VTE. Interestingly, CVC placement-a known thrombotic risk factor highlighted in several studies-was considered a confounder, while LOS, L-asparaginase use and nephrotic syndrome were confirmed as risk factors to HA-VTE. Large confidence intervals are related to the sample size; however, the results were significant

    Redução da densidade óssea alveolar em pacientes com artrite idiopática juvenil

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    OBJETIVOS: Avaliar a densidade óssea alveolar (DOA) na região dos primeiros molares superiores em pacientes com artrite idiopática juvenil (AIJ) e compará-la à de controles sistemicamente saudáveis. Como objetivos secundários, a influência da medicação e a atividade de doença reumática na DOA foram avaliadas, além da correlação entre a DOA e os parâmetros clínicos periodontais e reumatológicos. PACIENTES E MÉTODOS: Foram incluídos neste estudo 16 pacientes com AIJ (seis meninos e 10 meninas com idade média de 16,2 ± 2 anos) e 11 controles (seis meninos e cinco meninas com idade média de 16,4 ± 2,1 anos). A profundidade de sondagem (PS), o índice de placa visível (IPV), o índice de sangramento gengival (ISG) e o nível de inserção clínica (NIC) foram registrados. Radiografias bite-wings foram tiradas, e a DOA foi mensurada pelo sistema de radiografia digital RVG KODAK 6100, na região dos molares superiores. RESULTADOS: DOA, percentual de sítios com PS > 4 mm e ISG foram significativamente menores nos pacientes com AIJ, comparado aos controles (P = 0,001; P = 0,019; P = 0,011, respectivamente). A DOA não foi influenciada pela medicação nem pela atividade da AIJ, e não apresentou correlação com os parâmetros clínicos periodontais e reumatológicos. CONCLUSÃO: A DOA foi menor nos pacientes com AIJ, e parece não ser influenciada por medicação ou por atividade de doença reumática. Além disso, não foram observadas correlações entre a DOA e os indicadores clínicos periodontais e reumatológico
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