Browsing by Author "Santo, GC"
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- Adenosine Deaminase Two and Immunoglobulin M Accurately Differentiate Adult Sneddon's Syndrome of Unknown CausePublication . Santo, GC; Baldeiras, I; Guerreiro, R; Ribeiro, JA; Cunha, R; Youngstein, T; Nanthapisal, S; Leitão, J; Fernandes, C; Caramelo, F; Almeida, MR; Brás, J; Santana, IBACKGROUND: The association that exists between livedo reticularis (LR) and stroke is known as Sneddon's syndrome (SnS). The disorder is classified as primary SnS (PSnS), if the cause remains unknown and secondary SnS. The condition is rare and it occurs mainly sporadically. In 2014, 2 independent teams described a new genetic disorder with childhood-onset, which was called deficiency of adenosine deaminase 2 (DADA2), characterized by recurrent fevers and vascular pathologic features that included LR and stroke. All the patients carried recessively inherited mutations in cat eye syndrome chromosome region candidate 1 gene (CECR1), encoding the adenosine deaminase 2 (ADA2) protein. Genetic testing is the standard for the diagnosis of DADA2. However, the diagnostic accuracy of more affordable laboratorial analysis in CECR1-mutated individuals remains to be established. We aim to determine whether plasma ADA2 activity and serum immunoglobulin M (IgM) levels can distinguish (1) DADA2 from other adult patients within the SnS spectrum, and (2) healthy CECR1 heterozygous (HHZ) from healthy controls (HC). METHODS: ADA2 activity in plasma and serum IgM concentrations was measured in adult patients within the SnS spectrum, healthy first-degree relatives and HC. Genetic results were used as the reference standard. The primary outcome measures were sensitivity and specificity derived from receiver operating curve analysis. RESULTS: A total of 73 participants were included in the study: 26 patients with PSnS with no CECR1 mutation (PSnS), 6 bi-allelic (DADA2 patients) and 7 HHZ CECR1 mutations and 34 HC. Plasma ADA2 activity and serum IgM levels were significantly lower in DADA2 patients than in PSnS. With the use of the best indexes, plasma ADA2 activity differentiated PSnS from DADA2 with a sensitivity and specificity of 100.0% and HHZ from HC with a sensitivity of 97.1% and specificity of 85.7%. Serum IgM levels also differentiated PSnS from DADA2 with a sensitivity of 85.2% and specificity of 83.3%. CONCLUSION: Serum IgM levels might be used as a triage tool and plasma ADA2 activity performs perfectly as a diagnostic test for DADA2 in adult patients within the SnS spectrum. ADA2 activity in plasma also reliably distinguishes HHZ from HC.
- Adenosine Deaminase Two and Immunoglobulin M Accurately Differentiate Adult Sneddon's Syndrome of Unknown CausePublication . Santo, GC; Baldeiras, I; Guerreiro, R; Ribeiro, JA; Cunha, R; Youngstein, T; Nanthapisal, S; Leitão, J; Fernandes, C; Caramelo, F; Almeida, MR; Brás, J; Santana, IThe association that exists between livedo reticularis (LR) and stroke is known as Sneddon's syndrome (SnS). The disorder is classified as primary SnS (PSnS), if the cause remains unknown and secondary SnS. The condition is rare and it occurs mainly sporadically. In 2014, 2 independent teams described a new genetic disorder with childhood-onset, which was called deficiency of adenosine deaminase 2 (DADA2), characterized by recurrent fevers and vascular pathologic features that included LR and stroke. All the patients carried recessively inherited mutations in cat eye syndrome chromosome region candidate 1 gene (CECR1), encoding the adenosine deaminase 2 (ADA2) protein. Genetic testing is the standard for the diagnosis of DADA2. However, the diagnostic accuracy of more affordable laboratorial analysis in CECR1-mutated individuals remains to be established. We aim to determine whether plasma ADA2 activity and serum immunoglobulin M (IgM) levels can distinguish (1) DADA2 from other adult patients within the SnS spectrum, and (2) healthy CECR1 heterozygous (HHZ) from healthy controls (HC).
- Bilateral versus ipsilesional cortico-subcortical activity patterns in stroke show hemispheric dependencePublication . Vidal, AC; Banca, P; Pascoal, AG; Santo, GC; Sargento-Freitas, J; Gouveia, A; Castelo-Branco, MBackground Understanding of interhemispheric interactions in stroke patients during motor control is an important clinical neuroscience quest that may provide important clues for neurorehabilitation. In stroke patients, bilateral overactivation in both hemispheres has been interpreted as a poor prognostic indicator of functional recovery. In contrast, ipsilesional patterns have been linked with better motor outcomes. Aim We investigated the pathophysiology of hemispheric interactions during limb movement without and with contralateral restraint, to mimic the effects of constraint-induced movement therapy. We used neuroimaging to probe brain activity with such a movement-dependent interhemispheric modulation paradigm. Methods We used an fMRI block design during which the plegic/paretic upper limb was recruited/mobilized to perform unilateral arm elevation, as a function of presence versus absence of contralateral limb restriction ( n = 20, with balanced left/right lesion sites). Results Analysis of 10 right-hemispheric stroke participants yielded bilateral sensorimotor cortex activation in all movement phases in contrast with the unilateral dominance seen in the 10 left-hemispheric stroke participants. Superimposition of contralateral restriction led to a prominent shift from activation to deactivation response patterns, in particular in cortical and basal ganglia motor areas in right-hemispheric stroke. Left-hemispheric stroke was in general characterized by reduced activation patterns, even in the absence of restriction, which induced additional cortical silencing. Conclusion The observed hemispheric-dependent activation/deactivation shifts are novel and these pathophysiological observations suggest short-term neuroplasticity that may be useful for hemisphere-tailored neurorehabilitation.
- Blood Pressure Variability in Acute Ischemic Stroke: The Role of Early RecanalizationPublication . Martins, AI; Sargento-Freitas, J; Jesus-Ribeiro, J; Correia, I; Cardoso, L; Gomes, JP; Gonçalves, M; Costa, R; Silva, F; Galego, O; Nunes, C; Beato-Coelho, J; Varela, R; Machado, C; Rodrigues, B; Santo, GC; Cunha, LWe performed a retrospective study with the aim of investigating the association between blood pressure (BP) variability in the first 24 h after ischemic stroke and functional outcome, regarding arterial recanalization status. A total of 674 patients diagnosed with acute stroke and treated with revascularization therapies were enrolled. Systolic and diastolic BP values of the first 24 h after stroke were collected and their variation quantified through standard deviation. Recanalization state was evaluated at 6 h and clinical outcome at 3 months was assessed by modified Rankin Scale. In multivariate analyses systolic BP variability in the first 24 h post-stroke showed an association with 3 months clinical outcome in the whole population and non-recanalyzed patients. In recanalyzed patients, BP variability did not show a significant association with functional outcome.
- 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.