14,827 research outputs found

    Gyrification, cortical and subcortical morphometry in neurofibromatosis type 1: an uneven profile of developmental abnormalities.

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    Background: Neurofibromatosis type 1 (NF1) is a monogenic disorder associated with cognitive impairments. In order to understand how mutations in the NF1 gene impact brain structure it is essential to characterize in detail the brain structural abnormalities in patients with NF1. Previous studies have reported contradictory findings and have focused only on volumetric measurements. Here, we investigated the volumes of subcortical structures and the composite dimensions of the cortex through analysis of cortical volume, cortical thickness, cortical surface area and gyrification. Methods: We studied 14 children with NF1 and 14 typically developing children matched for age, gender, IQ and right/left-handedness. Regional subcortical volumes and cortical gyral measurements were obtained using the FreeSurfer software. Between-group differences were evaluated while controlling for the increase in total intracranial volume observed in NF1. Results: Subcortical analysis revealed disproportionately larger thalami, right caudate and middle corpus callosum in patients with NF1. Cortical analyses on volume, thickness and surface area were however not indicative of significant alterations in patients. Interestingly, patients with NF1 had significantly lower gyrification indices than typically developing children primarily in the frontal and temporal lobes, but also affecting the insula, cingulate cortex, parietal and occipital regions. Conclusions: The neuroanatomic abnormalities observed were localized to specific brain regions, indicating that particular areas might constitute selective targets for NF1 gene mutations. Furthermore, the lower gyrification indices were accompanied by a disproportionate increase in brain size without the corresponding increase in folding in patients with NF1. Taken together these findings suggest that specific neurodevelopmental processes, such as gyrification, are more vulnerable to NF1 dysfunction than others. The identified changes in brain organization are consistent with the patterns of cognitive dysfunction in the NF1 phenotype. © 2013 Violante et al

    Left ventricular aneurysms: early and long-term results of two types of repair

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    OBJECTIVE: Controversy still exists regarding the optimal surgical technique for postinfarction left ventricular (LV) aneurysm repair. We analyze the efficacy of two established techniques, linear vs. patch remodeling, for repair of dyskinetic LV aneurysms. METHODS: Between May 1988 and December 2001, 110 consecutive patients underwent repair of LV aneurysms. These represent 2.0% of a total group of 5429 patients who underwent isolated CABG during the period. Seventy-six (69.1%) patients were submitted to linear repair and 34 (30.9%) to patch remodelling. There were 94 (84.5%) men and 17 women, with a mean age of 59.2+/-9.2 years. Coronary surgery was performed in all patients (mean no. of grafts/patient, 2.7+/-0.8) and 14 (12.7%) had associated coronary endarterectomy. Forty-four (40.0%) patients had angina CCS class III/IV (linear 43.4%, patch 32.4%, NS) and the majority was in NYHA class I/II (88.2% in both groups). Left ventricular dysfunction (EF>40%) was present in 72 (65.5%) patients (linear 61.8%, patch 73.5%, NS). RESULTS: There was no perioperative mortality, and major morbidity was not significantly different between linear repair and patch repair groups. During a mean follow-up of 7.3+/-3.4 years (range 4-182 months) 14 patients (14.3%) had died, 12 (85.7%) of possible cardiac-related cause. Actual global survival rate was 85.7%. Actuarial survival rates at 5, 10 and 15 years were 91.3, 81.4 and 74%, respectively. There was no significant difference in late survival between the patch and the linear groups. At late follow-up the mean angina and NYHA class were, 1.3 (preoperative 2.4, P<0.001) and 1.5 (preoperative 1.7, NS), respectively, with no difference between the groups. There was no significant difference in hospital readmissions for cardiac causes (linear 22.8% and patch 37.0%). CONCLUSIONS: The technique of repair of postinfarction dyskinetic LV aneurysms should be adapted in each patient to the cavity size and shape, and the dimension of the scar. Both techniques achieved good results with respect to perioperative mortality, late functional status and surviva

    Linfoma de Hodgkin e Autoimunidade: Existirá uma Relação?

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    INTRODUCTION: The relationship between lymphomas and autoimmune diseases has been reported as bi-directional, however there is a few data in pediatric population. The aim of this work is to evaluate the prevalence of autoimmune diseases in children and adolescents with Hodgkin's lymphoma followed in a Pediatric Oncology Unit. MATERIAL AND METHODS: By reviewing Hodgkin's lymphomas data from the past 16 years (collected prospectively), an apparently large incidence of autoimmune diseases, mostly in female patients, was noted. We decided to do this retrospective study with an update on follow-up. Data analyzed: age, gender, autoimmune disease, temporal relation with lymphoma, lymphoma's stage, histologic subtype and treatment. RESULTS: Fifty-two cases were included, 7 (13.5%) of which, all female, had an autoimmune disease diagnosed previously, simultaneously or after lymphoma. Autoimmune diseases were: juvenile idiopathic arthritis, inflammatory bowel disease, Behçet's disease, autoimmune hepatitis, systemic erythematosus lupus, Hashimoto's thyroiditis and idiopathic thrombocytopenic purpura. The diagnosis was made after lymphoma in 4 patients, before in 2 and simultaneously in 1 patient. All cases, except the one with simultaneous diagnosis, are out of treatment and without oncologic disease relapse. No deaths were registered. DISCUSSION: There was an important prevalence of autoimmune diseases in girls with Hodgkin's lymphoma. We present data and discuss the possible causes based on a literature review. CONCLUSIONS: This relationship should be invoked, requiring more studies, especially in pediatric age.info:eu-repo/semantics/publishedVersio

    Repair in traumatic ascending aortic rupture and valve insufficiency

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    An 18-year-old patient who had chronic traumatic ascending aortic lesion and valve insufficiency, with severe LV dysfunction, was treated by repair of the aortic wall without prosthesis and of the aortic valve by a gluteraldehyde-treated autologous pericardial patch. The patient had an uneventful recovery and minimal residual aortic regurgitation at one-month echocardiographic follow-up. Conservative surgery of these lesions is feasible, with good results, in some cases

    18F-FDG-PET/CT in diagnosis of Q fever endocarditis

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    Relevância da Infecção VHC em Coagulopatias Congénitas

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    Introdução: A infecção pelo vírus da hepatite C (VHC) em doentes com coagulopatias congénitas (CC), como consequência da terapêutica empregue entre os anos 70 e 80 com transfusão de derivados de plasma humano, constitui um problema de saúde substancial e relevante. Objectivos: Análise e avaliação da relevância representada pela infecção VHC e suas complicações no tratamento duma população de doentes com CC. Métodos: Análise retrospectiva duma série de 161 doentes com CC tratados no Serviço de Imunohemoterapia do Centro Hospitalar de Lisboa Central (Lisboa, Portugal). Revisão sistemática de processos clínicos. Elaboração duma base de dados compreendendo a informação reunida e estudo estatístico das suas variáveis: idade, género, tipo e gravidade da coagulopatia e modalidade de tratamento. Relativamente à infecção por VHC: genotipo, tipo e duração do tratamento, frequência de resposta mantida ao tratamento e recidiva, co-infecções e complicações major e minor. Resultados: Dos 161 doentes 65 (40%) estão infectados pelo VHC. Dos doentes com hemofilia A: 36% são grave e 62% dos quais estão infectados pelo VHC; 9% moderada com 57%; 25% ligeira com 20%. No grupo da hemofilia B: 8% são grave com 23% infectados e 6% moderada ou ligeira com 10%. Relativamente ao grupo com doença de von Willebrand: 12% são tipo 2 com 16% infectados e 4% tipo 3 com 86%. Uma coorte de 26 doentes foi submetida a terapêutica para a infecção pelo VHC, com o primeiro doente a receber tratamento em 1993. Destes, 5 eram seropositivos para o VIH. O tratamento variou de monoterapia com interferão a terapêutica combinada de interferão ou interferão-peguilado com ribavirina. Conclusões: A infecção pelo VHC representa uma complicação significativa do tratamento empregue no passado na população em estudo. Considerando que a maioria destes doentes foi infectada nos finais dos anos 70 e início dos anos 80 assim como a evolução natural da infecção pelo VHC em doentes sem CC, prevê-se que a prevalência de complicações major deverá aumentar significativamente nos próximos anos. É de suma importância a implementação de medidas profilácticas na revisão e adaptação dos protocolos de seguimento de forma a prevenir a progressão da patologia hepática nestes doentes

    Causal Reasoning for Algorithmic Fairness

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    In this work, we argue for the importance of causal reasoning in creating fair algorithms for decision making. We give a review of existing approaches to fairness, describe work in causality necessary for the understanding of causal approaches, argue why causality is necessary for any approach that wishes to be fair, and give a detailed analysis of the many recent approaches to causality-based fairness

    Operationalizing Complex Causes: A Pragmatic View of Mediation

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    We examine the problem of causal response estimation for complex objects (e.g., text, images, genomics). In this setting, classical \emph{atomic} interventions are often not available (e.g., changes to characters, pixels, DNA base-pairs). Instead, we only have access to indirect or \emph{crude} interventions (e.g., enrolling in a writing program, modifying a scene, applying a gene therapy). In this work, we formalize this problem and provide an initial solution. Given a collection of candidate mediators, we propose (a) a two-step method for predicting the causal responses of crude interventions; and (b) a testing procedure to identify mediators of crude interventions. We demonstrate, on a range of simulated and real-world-inspired examples, that our approach allows us to efficiently estimate the effect of crude interventions with limited data from new treatment regimes
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