Browsing by Author "Palha, JA"
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- Assessing Cognitive Function in Older Adults Using a Videoconference ApproachPublication . Castanho, TC; Amorim, L; Moreira, PS; Mariz, J; Palha, JA; Sousa, N; Santos, NCBACKGROUND: The use of communication technologies is an emerging trend in healthcare and research. Despite efficient, reliable and accurate neuropsychological batteries to evaluate cognitive performance in-person, more diverse and less expensive and time consuming solutions are needed. Here we conducted a pilot study to determine the applicability of a videoconference (VC, Skype®) approach to assess cognitive function in older adults, using The Telephone Interview for Cognitive Status-Modified - Portuguese version (TICSM-PT). METHODS: After inclusion and exclusion criteria, 69 individuals (mean age=74.90±9.46years), selected from registries of local health centers and assisted-living facilities, were assessed on cognitive performance using videoconference, telephone and in-person approaches. FINDINGS: The videoconference administration method yielded comparable results to the traditional application. Correlation analyses showed high associations between the testing modalities: TICSM-PT VC and TICSM-PT telephone (r=0.885), TICSM-PT VC and MMSE face-to-face (r=0.801). Using the previously validated threshold for cognitive impairment on the TICSM-PT telephone, TICSM-PT VC administration presented a sensitivity of 87.8% and a specificity of 84.6%. INTERPRETATION: Findings indicate for the range of settings where videoconference approaches can be used, and for their applicability and acceptability, providing an alternative to current cognitive assessment methods. Continued validation studies and adaptation of neuropsychological instruments is warranted.
- Cortical maturation in fetuses referred for ‘isolated’ mild ventriculomegaly: a longitudinal ultrasound assessmentPublication . Miguelote, RF; Vides, B; Santos, RF; Palha, JA; Matias, A; Sousa, NOBJECTIVES: To compare cortical maturation between fetuses with isolated mild ventriculomegaly (IMV) and healthy fetuses, and to explore its potential prognostic value in IMV. METHODS: This prospective study quantified cortical maturation by ultrasound in 24 fetuses with IMV and 46 healthy fetuses. Depth and grading the developmental pattern of the parieto-occipital fissure (POF), calcarine fissure (CF) and sylvian fissure, and grading the Sylvian fissure operculization at 23-25, 27-28 and 31-32 weeks gestation were determined. RESULTS: At 23-25 and 27-28 gestational weeks, POF and CF mean depths were statistically lower in the IMV group. The POF and CF depth distribution had a normal distribution in the control group but displayed a bimodal distribution in the IMV group. IMV with progression of ventricular dilatation showed mean depth of CF lower than IMV in which ventriculomegaly regressed or remained stable. The sensitivity, specificity, positive predictive value and negative predictive value of a CF depth below the fifth percentile to predict progression of ventricular dilatation were, at 28 weeks, 100%, 88%, 67% and 100%, respectively. CONCLUSIONS: Cortical fissure assessment by ultrasound allowed the differentiation of a subgroup of IMV fetuses with a higher risk of progression of ventricular dilatation.
- Effector memory CD4(+) T cells are associated with cognitive performance in a senior populationPublication . Serre-Miranda, C; Roque, S; Santos, NC; Portugal-Nunes, C; Costa, P; Palha, JA; Sousa, N; Correia-Neves, MOBJECTIVE: Immunosenescence and cognitive decline are common markers of the aging process. Taking into consideration the heterogeneity observed in aging processes and the recently described link between lymphocytes and cognition, we herein explored the possibility of an association between alterations in lymphocytic populations and cognitive performance. METHODS: In a cohort of cognitively healthy adults (n = 114), previously characterized by diverse neurocognitive/psychological performance patterns, detailed peripheral blood immunophenotyping of both the innate and adaptive immune systems was performed by flow cytometry. RESULTS: Better cognitive performance was associated with lower numbers of effector memory CD4(+) T cells and higher numbers of naive CD8(+) T cells and B cells. Furthermore, effector memory CD4(+) T cells were found to be predictors of general and executive function and memory, even when factors known to influence cognitive performance in older individuals (e.g., age, sex, education, and mood) were taken into account. CONCLUSIONS: This is the first study in humans associating specific phenotypes of the immune system with distinct cognitive performance in healthy aging.
- 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.
- Stress Impact on Resting State Brain NetworksPublication . Soares, JM; Sampaio, A; Ferreira, LM; Santos, NC; Marques, PS; Marques, F; Palha, JA; Cerqueira, JJ; Sousa, NResting state brain networks (RSNs) are spatially distributed large-scale networks, evidenced by resting state functional magnetic resonance imaging (fMRI) studies. Importantly, RSNs are implicated in several relevant brain functions and present abnormal functional patterns in many neuropsychiatric disorders, for which stress exposure is an established risk factor. Yet, so far, little is known about the effect of stress in the architecture of RSNs, both in resting state conditions or during shift to task performance. Herein we assessed the architecture of the RSNs using functional magnetic resonance imaging (fMRI) in a cohort of participants exposed to prolonged stress (participants that had just finished their long period of preparation for the medical residence selection exam), and respective gender- and age-matched controls (medical students under normal academic activities). Analysis focused on the pattern of activity in resting state conditions and after deactivation. A volumetric estimation of the RSNs was also performed. Data shows that stressed participants displayed greater activation of the default mode (DMN), dorsal attention (DAN), ventral attention (VAN), sensorimotor (SMN), and primary visual (VN) networks than controls. Importantly, stressed participants also evidenced impairments in the deactivation of resting state-networks when compared to controls. These functional changes are paralleled by a constriction of the DMN that is in line with the pattern of brain atrophy observed after stress exposure. These results reveal that stress impacts on activation-deactivation pattern of RSNs, a finding that may underlie stress-induced changes in several dimensions of brain activity.
- The role of sex and sex-related hormones in cognition, mood and well-being in older men and womenPublication . Castanho, TC; Moreira, PS; Portugal-Nunes, C; Novais, A; Costa, PS; Palha, JA; Sousa, N; Santos, NCAlterations in hormone levels during aging impact on cognition and mood. Serum concentration levels of testosterone (TT), estradiol (E2), follicle-stimulating hormone (FSH), luteinizing hormone (LH), dehydroepiandrosterone sulfate (DHEAS) and prolactin (PRL) were assessed in 120 community-dwellers (51+ years of age, males and females), in a cross-sectional approach. Performance clusters based on executive functioning (GENEXEC), memory (MEM), mood and well-being were obtained. In males, higher PRL levels associated with worse cognitive performance, lower well-being, and higher scores in depression scales, and lower E2 with poorer cognition and higher depressive mood. DHEAS positively associated with GENEXEC and MEM. Nutritional status significantly associated with PRL (positively) and with DHEAS (negatively). Findings indicate that besides the more exhaustively studied E2 and TT, variations in the levels of sex-related hormones such as PRL, FSH, LH and DHEAS are of interest for the mental health aging profile particularly in men.