Browsing by Author "Marques, P"
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- Análise da devolução de medicamentos em dos unitáriaPublication . Castro, G; Machado, A; Abreu, B; Marcos, I; Marques, P; Fortunato, R; Barroso, S
- Análise da devolução de medicamentos em dose unitáriaPublication . Castro, G; Machado, A; Abreu, B; Marcos, I; Marques, P; Fortunato, R; Barroso, S
- Análise fármaco-económica da utilização de vinorrelbina oral versus vinorrelbina intravenosa no Hospital de BragaPublication . Plácido, A; Silva, A; Gomes, C; Gomes, J; Marques, P; Martins, S
- Brain functional connectivity is altered in patients with Takotsubo SyndromePublication . Silva, AR; Magalhães, R; Arantes, C; Moreira, PS; Rodrigues, M; Marques, P; Marques, J; Sousa, N; Pereira, VHTakotsubo syndrome (TTS) is an acute, reversible cardiomyopathy. The central autonomic nervous system (ANS) is believed to play a role in this disease. The aim of the present study was to investigate the patterns of brain functional connectivity in a sample of patients who had experienced a previous episode of TTS. Brain functional connectivity, both at rest and in response to the stressful stimulus of topical cold stimulation, was explored using functional magnetic resonance imaging (fMRI), network-based statistics (NBS) and graph theory analysis (GTA) in a population consisting of eight patients with a previous episode of TTS and eight sex- and age-matched controls. At rest, a network characterized by increased connectivity in the TTS group compared to controls and comprising elements of the central ANS was identified. GTA revealed increased local efficiency, clustering and strength in regions of the bilateral hippocampus in subjects with a previous episode of TTS. When stressed by local exposure to cold, the TTS group differed significantly from both a pre-stress baseline interval and from the control group, showing increased connectivity in a network that included the left amygdala and the right insula. Based on the results, patients with TTS display a reorganization of cortical and subcortical networks, including areas associated with the emotional response and autonomic regulation. The findings tend to support the hypothesis that a deregulation of autonomic control at the central level plays a significant role in this syndrome.
- Brain structure across the lifespan: the influence of stress and moodPublication . Soares, JM; Marques, P; Magalhães, R; Santos, NC; Sousa, NNormal brain aging is an inevitable and heterogeneous process characterized by a selective pattern of structural changes. Such heterogeneity arises as a consequence of cumulative effects over the lifespan, including stress and mood effects, which drive different micro- and macro-structural alterations in the brain. Investigating these differences in healthy age-related changes is a major challenge for the comprehension of the cognitive status. Herein we addressed the impact of normal aging, stress, mood, and their interplay in the brain gray and white matter (WM) structure. We showed the critical impact of age in the WM volume and how stress and mood influence brain volumetry across the lifespan. Moreover, we found a more profound effect of the interaction of aging/stress/mood on structures located in the left hemisphere. These findings help to clarify some divergent results associated with the aging decline and to enlighten the association between abnormal volumetric alterations and several states that may lead to psychiatric disorders.
- Hiperaldosteronismo primário: resultados do primeiro estudo multicêntrico português realizado pelo Grupo de Estudos de Tumores da Supra-RenalPublication . Fernandes, V; Silva, T; Martins, D; Gonçalves, D; Almeida, R; Monteiro, AM; Neves, C; Simões, H; Marques, P; Serra, F; Pereira, ML; Grupo de Estudos de Tumores da Supra-RenalIntroduction: Primary Aldosteronism (PA) is the most prevalent cause of secondary hypertension. Nevertheless, there is no portuguese multicenter study characterizing PA patients. Aims: To characterize the clinical presentation, diagnostic workup, treatment and follow-up of patients with confirmed PA. Methods: Retrospective multicenter study of PA patients followed in 9 portuguese hospitals. Results: Sixty-three cases were selected with a mean age of diagnosis of 52.1 ± 13.1 years, 9.9 years after the diagnosis of hypertension. At presentation, 37 cases (60.7%) had hypertension, 11 (22.9%) had resistant hypertension and 20 (32.8%) of patients had hipokalemia (mean 3.2 mmol/L). Baseline laboratory showed a mean serum aldosterone of 33.4ng/dL, plasmatic renin activity (PRA) of 0.2ng/mL/h with an aldosterone/PRA ratio of 97.1. Confirmatory testing was performed with saline infusion in 55 patients (positive in 84.4%) and captopril test in 14 (positive in 85.7%). Imaging showed adenomas in 55 cases, hyperplasia in 2 and bilateral cases in 8. Arterial venous sampling (AVS) was performed in 9 patients (14,5%) and was conclusive in 1. Iodocholesterol scintigraphy was done in 14 cases (22%) with unilateral fixation in 9 and no fixation in 4. Patients were treated with laparoscopic adrenalectomy in 28 cases (58.3%) and mineralocorticoid receptor antagonists in 20 cases (41.7%). The surgical treated group had less duration of hypertension (8 versus 14 years, p = 0.002), higher prevalence of anti-hypertensive drugs at presentation (100 versus 75% p = 0.009) and bigger tumour size (1.8 versus 1.5 cm, p = 0.022). During follow-up there was a trend towards a greater proportion of patients with no hypertension improvement in the medical treatment group (29.4% versus 7.4%, p = 0.089). Conclusion: This is the first Portuguese PA multicenter study. It suggests that PA remains an under- -diagnosed condition with a significant delay in diagnosis. Surgical treated patients had a more aggressive disease and showed a trend towards better hypertension control.
- Plasticity of resting state brain networks in recovery from stressPublication . Soares, JM; Sampaio, A; Marques, P; Ferreira, LM; Santos, NC; Marques, F; Palha, JA; Cerqueira, JJ; Sousa, NChronic stress has been widely reported to have deleterious impact in multiple biological systems. Specifically, structural and functional remodeling of several brain regions following prolonged stress exposure have been described; importantly, some of these changes are eventually reversible. Recently, we showed the impact of stress on resting state networks (RSNs), but nothing is known about the plasticity of RSNs after recovery from stress. Herein, we examined the "plasticity" of RSNs, both at functional and structural levels, by comparing the same individuals before and after recovery from the exposure to chronic stress; results were also contrasted with a control group. Here we show that the stressed individuals after recovery displayed a decreased resting functional connectivity in the default mode network (DMN), ventral attention network (VAN), and sensorimotor network (SMN) when compared to themselves immediately after stress; however, this functional plastic recovery was only partial as when compared with the control group, as there were still areas of increased connectivity in dorsal attention network (DAN), SMN and primary visual network (VN) in participants recovered from stress. Data also shows that participants after recovery from stress displayed increased deactivations in DMN, SMN, and auditory network (AN), to levels similar to those of controls, showing a normalization of the deactivation pattern in RSNs after recovery from stress. In contrast, structural changes (volumetry) of the brain areas involving these networks are absent after the recovery period. These results reveal plastic phenomena in specific RSNs and a functional remodeling of the activation-deactivation pattern following recovery from chronic-stress, which is not accompanied by significant structural plasticity.
- The Bounds Of Education In The Human Brain ConnectomePublication . Marques, P; Soares, JM; Magalhães, R; Santos, NC; Sousa, NInter-individual heterogeneity is evident in aging; education level is known to contribute for this heterogeneity. Using a cross-sectional study design and network inference applied to resting-state fMRI data, we show that aging was associated with decreased functional connectivity in a large cortical network. On the other hand, education level, as measured by years of formal education, produced an opposite effect on the long-term. These results demonstrate the increased brain efficiency in individuals with higher education level that may mitigate the impact of age on brain functional connectivity.