Browsing by Author "Ferreira, C"
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- Anatomical characteristics of the styloid process in internal carotid artery dissection: Case-control studyPublication . Amorim, JM; Pereira, D; Rodrigues, MG; Beato-Coelho, J; Lopes, M; Cunha, A; Figueiredo, S; Mendes-Pinto, M; Ferreira, C; Sargento-Freitas, J; Castro, S; Pinho, JIntroduction Pathophysiology of cervical artery dissection is complex and poorly understood. In addition to well-known causative and predisposing factors, including major trauma and monogenic connective tissue disorders, morphological characteristics of the styloid process have been recently recognized as a possible risk factor for cervical internal carotid artery dissection. Aims To study the association of the anatomical characteristics of styloid process with internal carotid artery dissection. Methods Retrospective, multicenter, case-control study of patients with internal carotid artery dissection and age- and sex-matched controls. Consecutive patients with internal carotid artery dissection and controls with ischemic stroke or transient ischemic attack of any etiology excluding internal carotid artery dissection, who had performed computed tomography angiography, diagnosed between January 2010 and September 2016. Two independent observers measured styloid process length and styloid process distance to internal carotid artery. Results Sixty-two patients with internal carotid artery dissection and 70 controls were included. Interobserver agreement was good for styloid process length and styloid process-internal carotid artery distance (interclass correlation coefficient = 0.89 and 0.76, respectively). Styloid process ipsilateral to dissection was longer than left and right styloid process in controls (35.8 ± 14.4 mm versus 30.4 ± 8.9 mm and 30.3 ± 8.2 mm, p = 0.011 and p = 0.008, respectively). Styloid process-internal carotid artery distance ipsilateral to dissection was shorter than left and right distance in controls (6.3 ± 1.9 mm versus 7.2 ± 2.1 mm and 7.0 ± 2.3 mm, p = 0.003 and p = 0.026, respectively). Internal carotid artery dissection was associated with styloid process length (odds ratio = 1.04 mm-1, 95% confidence interval = 1.01-1.08, p = 0.015) and styloid process-internal carotid artery distance (OR = 0.77 mm-1, 95% confidence interval = 0.64-0.92, p = 0.004). Conclusion Longer styloid process and shorter distance between styloid process and cervical internal carotid artery are associated with cervical internal carotid artery dissection.
- Endothelial Progenitor Cells influence acute and subacute stroke hemodynamicsPublication . Sargento-Freitas, J; Aday, S; Nunes, C; Cordeiro, M; Gouveia, A; Silva, F; Machado, C; Rodrigues, B; Santo, GC; Ferreira, C; Castelo-Branco, M; Ferreira, L; Cunha, LBACKGROUND: 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.
- Ethical limits for noninvasive ventilation prescription.Publication . Mendes, MS; Ferreira, C; Dias, C; Moita, J
- Genetic screening of Alzheimer's disease genes in Iberian and African samples yields novel mutations in presenilins and APPPublication . Guerreiro, RJ; Baquero, M; Blesa, R; Boada, M; Bras, JM; Bullido, MJ; Calado, A; Crook, R; Ferreira, C; Frank, A; Machado, A; Oliveira, CR; Santana, IMutations in three genes (PSEN1, PSEN2, and APP) have been identified in patients with early-onset (<65 years) Alzheimer's disease (AD). We performed a screening for mutations in the coding regions of presenilins, as well as exons 16 and 17 of the APP gene in a total of 231 patients from the Iberian peninsular with a clinical diagnosis of early-onset AD (mean age at onset of 52.9 years; range 31-64). We found three novel mutations in PSEN1, one novel mutation in PSEN2, and a novel mutation in the APP gene. Four previously described mutations in PSEN1 were also found. The same analysis was carried in 121 elderly healthy controls from the Iberian peninsular, and a set of 130 individuals from seven African populations belonging to the Centre d'Etude du Polymorphisme Humain-Human Genome Diversity Panel (CEPH-HGDP), in order to determine the extent of normal variability in these genes. Interestingly, in the latter series, we found five new non-synonymous changes in all three genes and a presenilin 2 variant (R62H) that has been previously related to AD. In some of these mutations, the pathologic consequence is uncertain and needs further investigation. To address this question we propose and use a systematic algorithm to classify the putative pathology of AD mutations.
- Primary Bilateral Thalamic Astrocytoma Presenting With Head Tremor, Ataxia, and DementiaPublication . Machado, A; Ribeiro, M; Rodrigues, M; Ferreira, C; Almeida, R; Santana, I; Castro, L; Carpenter, S
- Prognostic Value of Isolated Elevated Troponin I Levels in Patients without Acute Coronary Syndrome Admitted to the Emergency DepartmentPublication . Domingues, C; Ferreira, MJ; Ferreira, JM; Marinho, AV; Alves, PM; Ferreira, C; Fonseca, I; Gonçalves, LBackground: Although non-ischemic troponin elevation is frequently seen in patients admitted to the emergency department (ED), consensus regarding its management is lacking. Objectives: This study aimed to characterize patients admitted to the ED with non-ischemic troponin elevation and to identify potential mortality predictors in this population. Methods: This retrospective observational study included ED patients with a positive troponin test result between June and July of 2015. Patients with a clinical diagnosis of acute coronary syndrome (ACS) were excluded. Data on patient demographics and clinical and laboratory variables were extracted from medical records. Follow-up data were obtained for 16 months or until death occurred. The statistical significance level was 5%. Results: Troponin elevation without ACS was found in 153 ED patients. The median (IQR) patient age was 78 (19) years, 80 (52.3%) were female and 59(38.6%) died during follow-up. The median (IQR) follow-up period was 477(316) days. Survivors were significantly younger 76 (24) vs. 84 (13) years; p=0.004) and featured a higher proportion of isolated troponin elevation (without creatine kinase or myoglobin elevation) in two consecutive evaluations: 48 (53.9%) vs. 8 (17.4%), p<0.001. Survivors also presented a lower rate of antiplatelet treatment and same-day hospitalization. In the multivariate logistic regression with adjustment for significant variables in the univariate analysis, isolated troponin elevation in two consecutive evaluations showed a hazard ratio= 0.43 (95%CI 0.17-0.96, p=0.039); hospitalization, previous antiplatelet treatment and age remained independently associated with mortality. Conclusions: Isolated troponin elevation in two consecutive measurements was a strong predictor of survival in ED patients with troponin elevation but without ACS.
- Quantitative evaluation of a pulmonary contour segmentation algorithm in X-ray computed tomography imagesPublication . Sousa-Santos, B; Ferreira, C; Silva, JS; Teixeira, LRATIONALE AND OBJECTIVES: Pulmonary contour extraction from thoracic x-ray computed tomography images is a mandatory preprocessing step in many automated or semiautomated analysis tasks. This study was conducted to quantitatively assess the performance of a method for pulmonary contour extraction and region identification. MATERIALS AND METHODS: The automatically extracted contours were statistically compared with manually drawn pulmonary contours detected by six radiologists on a set of 30 images. Exploratory data analysis, nonparametric statistical tests, and multivariate analysis were used, on the data obtained using several figures of merit, to perform a study of the interobserver variability among the six radiologists and the contour extraction method. The intraobserver variability of two human observers was also studied. RESULTS: In addition to a strong consistency among all of the quality indexes used, a wider interobserver variability was found among the radiologists than the variability of the contour extraction method when compared with each radiologist. The extraction method exhibits a similar behavior (as a pulmonary contour detector), to the six radiologists, for the used image set. CONCLUSION: As an overall result of the application of this evaluation methodology, the consistency and accuracy of the contour extraction method was confirmed to be adequate for most of the quantitative requirements of radiologists. This evaluation methodology could be applied to other scenarios.
- Quantitative Genetics Validates Previous Genetic Variants and Identifies Novel Genetic Players Influencing Alzheimer's Disease Cerebrospinal Fluid BiomarkersPublication . Ramos de Matos, M; Ferreira, C; Herukka, SK; Soininen, H; Janeiro, A; Santana, I; Baldeiras, I; Almeida, MR; Lleó, A; Dols-Icardo, O; Alcolea, D; Benussi, L; Binetti, G; Paterlini, A; Ghidoni, R; Nacmias, B; Meulenbroek, O; van Waalwijk van Doorn, LJ; Kuiperi, HJ; Hausner, L; Waldemar, G; Simonsen, AH; Tsolaki, M; Gkatzima, O; Resende de Oliveira, C; Verbeek, MM; Clarimon, J; Hiltunen, M; de Mendonça, A; Martins, MCerebrospinal fluid (CSF) biomarkers have been extensively investigated in the Alzheimer's disease (AD) field, and are now being applied in clinical practice. CSF amyloid-beta (Aβ1-42), total tau (t-tau), and phosphorylated tau (p-tau) reflect disease pathology, and may be used as quantitative traits for genetic analyses, fostering the identification of new genetic factors and the proposal of novel biological pathways of the disease. In patients, the concentration of CSF Aβ1-42 is decreased due to the accumulation of Aβ1-42 in amyloid plaques in the brain, while t-tau and p-tau levels are increased, indicating the extent of neuronal damage. To better understand the biological mechanisms underlying the regulation of AD biomarkers, and its relation to AD, we examined the association between 36 selected single nucleotide polymorphisms (SNPs) and AD biomarkers Aβ1-42, t-tau, and p-tau in CSF in a cohort of 672 samples (571 AD patients and 101 controls) collected within 10 European consortium centers.Our results highlighted five genes, APOE, LOC100129500, PVRL2, SNAR-I, and TOMM40, previously described as main players in the regulation of CSF biomarkers levels, further reinforcing a role for these in AD pathogenesis. Three new AD susceptibility loci, INPP5D, CD2AP, and CASS4, showed specific association with CSF tau biomarkers. The identification of genes that specifically influence tau biomarkers point out to mechanisms, independent of amyloid processing, but in turn related to tau biology that may open new venues to be explored for AD treatment.
- Renal abscesses in childhood: report of two uncommon casesPublication . Cancelinha, C; Santos, L; Ferreira, C; Gomes, C
- Transplantação renal em doentes com diabetes mellitus tipo I e tipo IIPublication . Baptista, C; Bastos, M; Gomes, L; Macário, F; Ruas, L; Rodrigues, D; Alves, R; Gomes, H; Ferreira, C; Roseiro, A; Paiva, S; Barros, L; Carvalheiro, M; Mota, A; Furtado, AL; Ruas, AA total of 618 patients with end-stage renal disease received kidney transplants between 1980 and September 1996. Twenty eight of them were diabetics. Better results were achieved for type 1 diabetic patients than for type 2 (mortality: 5.9% vs 27.3%; functioning graft: 88.2% vs 72.7%). The morbility was also higher in those patients (infections: 81.8% vs 29.4%; vascular complications: 45.5% vs 17.6%). Actuarial patient and graft survival were lower for type 2 than for non diabetic patients. For type 1 diabetics the results are similar to those for non diabetics. Better results can probably be achieved by restricting the selection criteria. The decision to transplant or maintain on dialysis should be made on a case by case basis.