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1.
J Med Internet Res ; 21(11): e14269, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697244

RESUMO

BACKGROUND: Although the availability and use of mobile mental health apps has grown exponentially in recent years, little data are available regarding their efficacy. OBJECTIVE: This study aimed to evaluate the effectiveness of an app developed to promote stress management and well-being among working women compared with a control app. METHODS: Female employees at a private hospital were invited to participate in the study via mailing lists and intranet ads. A total of 653 individuals self-enrolled through the website. Eligible participants were randomized between control (n=240) and intervention (n=250) groups. The well-being mobile app provides an 8-week program with 4 classes per week (including a brief theoretical portion and a 15-min guided practice). The active control app also provided 4 assessments per week that encouraged participants to self-observe how they were feeling for 20 min. We also used the app to conduct Web-based questionnaires (10-item Perceived Stress Scale and 5-item World Health Organization Well-Being Index) and ask specific questions to assess subjective levels of stress and well-being at baseline (t1), midintervention (t4=4 weeks after t1) and postintervention (t8=8 weeks after t1). Both apps were fully automated without any human involvement. Outcomes from the control and intervention conditions at the 3 time points were analyzed using a repeated measures analysis of variance. RESULTS: Among the randomized participants (n=490), 185 participants were excluded at the 4-week follow-up and another 79 at the 8-week follow-up because of noncompliance with the experimental protocol. Participants who did not complete t4 and t8 assessments were equally distributed between groups (t4: control group=34.6% [83/240] and intervention group=40.8% [102/250]; P=.16; t8: control group=29.9% [47/157] and intervention group=21.6% [32/148]; P=.10). Both groups showed a significant increase in general well-being as a function of time (F2,426=5.27; P=.006), but only the intervention group presented a significant increase in work-related well-being (F2,426=8.92; P<.001), as well as a significant reduction in work-related and overall stress (F2,426=5.50; P=.004 and F2,426=8.59; P<.001, respectively). CONCLUSIONS: The well-being mobile app was effective in reducing employee stress and improving well-being. TRIAL REGISTRATION: Clinicaltrials.gov NCT02637414; https://clinicaltrials.gov/ct2/show/NCT02637414.


Assuntos
Mão de Obra em Saúde/normas , Saúde Mental/normas , Aplicativos Móveis/estatística & dados numéricos , Estresse Fisiológico/fisiologia , Adulto , Feminino , Humanos , Psicoterapia
2.
Clin Colorectal Cancer ; 18(1): 19-27, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30297263

RESUMO

PURPOSE: Chemotherapy-related cognitive impairment can occur in cancer survivors after treatment, especially those patients who have undergone chemotherapy for breast cancer. The frequency and to what extent such toxicity develops in colorectal cancer (CRC) survivors is unknown. The present prospective study evaluated the effects of adjuvant chemotherapy on the cognitive performance of patients with localized CRC compared with a control group who had not undergone chemotherapy. PATIENTS AND METHODS: Consecutive patients with localized stage II and III CRC completed neuropsychological assessments, self-reported cognitive complaint questionnaires, and depressive symptom evaluations before starting fluoropyrimidine-based adjuvant chemotherapy and after 12 months. Blood was collected for apolipoprotein E genotyping. Diffusion tensor imaging data were acquired from a subset of participants at both evaluation points. RESULTS: From December 2012 to December 2014, 137 patients were approached and 85 were included. Of these 85 patients, 49 had undergone chemotherapy and 26 had not, in accordance with the standard recommendations for adjuvant therapy for CRC. The mean age was 62.5 ± 9.4 years, 60% were men, and the mean educational attainment was 7.6 ± 3.7 years. No difference was found in the global composite score (P = .38), attention (P = .84), or memory (P = .97) between the 2 groups during the follow-up period (mean ± standard deviation, 375 ± 29 days). However, a statistically significant difference was found for executive function after adjustment for age, sex, education, and depressive symptoms at baseline (ß -1.80; 95% confidence interval, -3.50 to -0.11; P = .04), suggesting worse performance for the chemotherapy group. For the 32 patients who had undergone magnetic resonance imaging, tract-based spatial statistics did not show voxelwise significant differences in structural brain connectivity at baseline or during follow-up. Apolipoprotein E polymorphisms were not predictive of cognitive dysfunction. CONCLUSION: Patients with CRC who received adjuvant 5-fluorouracil with or without oxaliplatin presented with a decline in executive function after 12 months compared with patients with localized disease who had not received chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transtornos Cognitivos/tratamento farmacológico , Neoplasias Colorretais/complicações , Idoso , Estudos de Casos e Controles , Quimioterapia Adjuvante , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Neoplasias Colorretais/patologia , Imagem de Tensor de Difusão , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Oxaliplatina/administração & dosagem , Prognóstico , Estudos Prospectivos , Inquéritos e Questionários
3.
Neuroreport ; 29(17): 1463-1467, 2018 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-30222724

RESUMO

BACKGROUND AND PURPOSE: Among several cognitive advantages, meditation is thought to enhance practitioners' capacity for sustained attention. In the present study, we explored this question by testing meditation practitioners (meditators) and nonpractitioners (nonmeditators) on a task that requires sustained attention, the Stroop Word-Color Task (SWCT), while using functional MRI. PARTICIPANTS AND METHODS: Participants were all right-handed and included 23 regular meditators as well as 17 nonmeditators. Participants viewed color words (i.e. 'red,' 'blue,' or 'green') presented one at a time on the screen that were written in either the same color (congruent condition) or a different color (incongruent condition) and were asked to indicate the color of the print. Participants also viewed noncolor words written in unrelated colors (neutral condition). Both groups completed the same two acquisition runs. RESULTS: Although both meditators and nonmeditators gave faster responses on run 2 than run 1 for both the neutral and incongruent trials, nonmeditators showed decreased activation and meditators showed increased activation in precuneus/posterior cingulate cortex. These regions were previously shown to be activated in the SWCT and belong to default mode network as well as to cognitive control network. CONCLUSION: Attention to repetitive stimuli during two equal runs of SWCT is mediated by the precuneus/posterior cingulate cortex, and mental training through meditation may influence the activity of these regions during such tasks.


Assuntos
Atenção/fisiologia , Giro do Cíngulo/fisiologia , Meditação , Lobo Parietal/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Teste de Stroop
4.
Explore (NY) ; 14(5): 352-356, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30122327

RESUMO

OBJECTIVE: To compare cognition and brain function in elderly Tai Chi and Water Aerobics practitioners. METHODS: Eight Tai Chi (TC) and 8 Water Aerobics (WA) practitioners matched by gender, education and age underwent neuropsychological and fMRI scan during attention (Stroop Word Color Task) and working memory (N Back) tasks. RESULTS: Groups were similar for demographic and cognitive variables. Besides anxiety (smaller in TC group), there were no differences between groups in neuropsychological variables. During the Stroop Word Color Task, TC group had smaller brain activation in the right intracalcarine cortex, lateral occipital cortex, and occipital pole, than WA. During N back, TC group presented smaller brain activation in the right frontal pole and superior frontal gyrus. CONCLUSION: Despite the small number of participants in this preliminary study, both groups had similar cognitive performance, however the Tai Chi group required less brain activation to perform the attention and memory tasks, therefore they may have a more efficient cognitive performance than Water Aerobics group.


Assuntos
Atenção , Encéfalo/fisiologia , Cognição , Exercício Físico/psicologia , Memória de Curto Prazo , Tai Chi Chuan/psicologia , Idoso , Ansiedade , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Água
5.
Front Hum Neurosci ; 12: 222, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29942255

RESUMO

Meditation as a cognitive enhancement technique is of growing interest in the field of health and research on brain function. The Stroop Word-Color Task (SWCT) has been adapted for neuroimaging studies as an interesting paradigm for the understanding of cognitive control mechanisms. Performance in the SWCT requires both attention and impulse control, which is trained in meditation practices. We presented SWCT inside the MRI equipment to measure the performance of meditators compared with non-meditators before and after a meditation retreat. The aim of this study was to evaluate the effects of a 7-day Zen intensive meditation training (a retreat) on meditators and non-meditators in this task on performance level and neural mechanisms. Nineteen meditators and 14 non-meditators were scanned before and after a 7-day Zen meditation retreat. No significant differences were found between meditators and non-meditators in the number of the correct responses and response time (RT) during SWCT before and after the retreat. Probably, due to meditators training in attention, their brain activity in the contrast incongruent > neutral during the SWCT in the anterior cingulate, ventromedial prefrontal cortex/anterior cingulate, caudate/putamen/pallidum/temporal lobe (center), insula/putamen/temporal lobe (right) and posterior cingulate before the retreat, were reduced compared with non-meditators. After the meditation retreat, non-meditators had reduced activation in these regions, becoming similar to meditators before the retreat. This result could be interpreted as an increase in the brain efficiency of non-meditators (less brain activation in attention-related regions and same behavioral response) promoted by their intensive training in meditation in only 7 days. On the other hand, meditators showed an increase in brain activation in these regions after the same training. Intensive meditation training (retreat) presented distinct effects on the attention-related regions in meditators and non-meditators probably due to differences in expertise, attention processing as well as neuroplasticity.

6.
Parkinsonism Relat Disord ; 49: 54-59, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29402698

RESUMO

INTRODUCTION: Chorea-acanthocytosis (ChAc) and Huntington's disease (HD) are neurodegenerative conditions that share clinical and neuropathological features, despite their distinct genetic etiologies. METHODS: In order to compare these neuropathologies, serial gallocyanin-stained brain sections from three subjects with ChAc were analyzed and compared with our previous studies of eight HD cases, in addition to three hemispheres from two male controls. RESULTS: Astrogliosis was much greater in the ChAc striatum, as compared to that found in HD, with dramatic increase in total striatal glia numbers and the number of glia per striatal neuron. Striatal astrocytes are most likely derived from the striatal subependymal layer in ChAc, which showed massive proliferation. The thalamic centromedian-parafascicular complex is reciprocally connected to the striatum and is more heavily affected in HD than in ChAc. CONCLUSION: The distinct patterns of selective vulnerability and gliosis observed in HD and ChAc challenge simplistic views on the pathogenesis of these two diseases with rather similar clinical signs. The particular roles played by astroglia in ChAc and in HD clearly need to be elucidated in more detail.


Assuntos
Corpo Estriado/patologia , Gliose/patologia , Doença de Huntington/patologia , Neuroacantocitose/patologia , Tálamo/patologia , Atrofia/patologia , Corpo Estriado/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tálamo/citologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-25571267

RESUMO

We propose a new Blind Source Separation technique for whole-brain activity estimation that best profits from FMRI's intrinsic spatial sparsity. The Local Sparse Component Analysis (LSCA) combines wavelet analysis, group-separable regularizers, contiguity-constrained clusterization and principal components analysis (PCA) into a unique spatial sparse representation of FMRI images towards efficient dimensionality reduction without sacrificing physiological characteristics by avoiding artificial stochastic model constraints. The LSCA outperforms classical PCA source reconstruction for artificial data sets over many noise levels. A real FMRI data illustration reveals resting-state activities in regions hard to observe, such as thalamus and basal ganglia, because of their small spatial scale.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Algoritmos , Gânglios da Base/patologia , Encéfalo/patologia , Análise por Conglomerados , Simulação por Computador , Humanos , Movimento (Física) , Análise de Componente Principal , Análise de Regressão , Razão Sinal-Ruído , Processos Estocásticos , Tálamo/patologia , Análise de Ondaletas
8.
PLoS One ; 7(7): e39832, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22802944

RESUMO

Multivariate pattern recognition approaches have become a prominent tool in neuroimaging data analysis. These methods enable the classification of groups of participants (e.g. controls and patients) on the basis of subtly different patterns across the whole brain. This study demonstrates that these methods can be used, in combination with automated morphometric analysis of structural MRI, to determine with great accuracy whether a single subject has been engaged in regular mental training or not. The proposed approach allowed us to identify with 94.87% accuracy (p<0.001) if a given participant is a regular meditator (from a sample of 19 regular meditators and 20 non-meditators). Neuroimaging has been a relevant tool for diagnosing neurological and psychiatric impairments. This study may suggest a novel step forward: the emergence of a new field in brain imaging applications, in which participants could be identified based on their mental experience.


Assuntos
Imageamento por Ressonância Magnética/métodos , Meditação , Neuroimagem , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Máquina de Vetores de Suporte
9.
Neuroimage ; 59(1): 745-9, 2012 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-21763432

RESUMO

Meditation is a mental training, which involves attention and the ability to maintain focus on a particular object. In this study we have applied a specific attentional task to simply measure the performance of the participants with different levels of meditation experience, rather than evaluating meditation practice per se or task performance during meditation. Our objective was to evaluate the performance of regular meditators and non-meditators during an fMRI adapted Stroop Word-Colour Task (SWCT), which requires attention and impulse control, using a block design paradigm. We selected 20 right-handed regular meditators and 19 non-meditators matched for age, years of education and gender. Participants had to choose the colour (red, blue or green) of single words presented visually in three conditions: congruent, neutral and incongruent. Non-meditators showed greater activity than meditators in the right medial frontal, middle temporal, precentral and postcentral gyri and the lentiform nucleus during the incongruent conditions. No regions were more activated in meditators relative to non-meditators in the same comparison. Non-meditators showed an increased pattern of brain activation relative to regular meditators under the same behavioural performance level. This suggests that meditation training improves efficiency, possibly via improved sustained attention and impulse control.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Meditação , Adulto , Mapeamento Encefálico , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Teste de Stroop , Análise e Desempenho de Tarefas
10.
Int J Nanomedicine ; 6: 591-603, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21674016

RESUMO

Gliomas are a group of heterogeneous primary central nervous system (CNS) tumors arising from the glial cells. Malignant gliomas account for a majority of malignant primary CNS tumors and are associated with high morbidity and mortality. Glioblastoma is the most frequent and malignant glioma, and despite the recent advances in diagnosis and new treatment options, its prognosis remains dismal. New opportunities for the development of effective therapies for malignant gliomas are urgently needed. Magnetic hyperthermia (MHT), which consists of heat generation in the region of the tumor through the application of magnetic nanoparticles subjected to an alternating magnetic field (AMF), has shown positive results in both preclinical and clinical assays. The aim of this review is to assess the relevance of hyperthermia induced by magnetic nanoparticles in the treatment of gliomas and to note the possible variations of the technique and its implication on the effectiveness of the treatment. We performed an electronic search in the literature from January 1990 to October 2010, in various databases, and after application of the inclusion criteria we obtained a total of 15 articles. In vitro studies and studies using animal models showed that MHT was effective in the promotion of tumor cell death and reduction of tumor mass or increase in survival. Two clinical studies showed that MHT could be applied safely and with few side effects. Some studies suggested that mechanisms of cell death, such as apoptosis, necrosis, and antitumor immune response were triggered by MHT. Based on these data, we could conclude that MHT proved to be efficient in most of the experiments, and that the improvement of the nanocomposites as well as the AMF equipment might contribute toward establishing MHT as a promising tool in the treatment of malignant gliomas.


Assuntos
Glioma/terapia , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/uso terapêutico , Animais , Humanos
11.
Neuroimage ; 47(2): 467-72, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19398020

RESUMO

Depression is the most frequent psychiatric disorder in Parkinson's disease (PD). Although evidence suggests that depression in PD is related to the degenerative process that underlies the disease, further studies are necessary to better understand the neural basis of depression in this population of patients. In order to investigate neuronal alterations underlying the depression in PD, we studied thirty-six patients with idiopathic PD. Twenty of these patients had the diagnosis of major depression disorder and sixteen did not. The two groups were matched for PD motor severity according to Unified Parkinson Disease Rating Scale (UPDRS). First we conducted a functional magnetic resonance imaging (fMRI) using an event-related parametric emotional perception paradigm with test retest design. Our results showed decreased activation in the left mediodorsal (MD) thalamus and in medial prefrontal cortex in PD patients with depression compared to those without depression. Based upon these results and the increased neuron count in MD thalamus found in previous studies, we conducted a region of interest (ROI) guided voxel-based morphometry (VBM) study comparing the thalamic volume. Our results showed an increased volume in mediodorsal thalamic nuclei bilaterally. Converging morphological changes and functional emotional processing in mediodorsal thalamus highlight the importance of limbic thalamus in PD depression. In addition this data supports the link between neurodegenerative alterations and mood regulation.


Assuntos
Depressão/diagnóstico , Depressão/patologia , Sistema Límbico/patologia , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Tálamo/patologia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade
13.
Biol Cybern ; 97(1): 33-45, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17534651

RESUMO

The number of studies using functional magnetic resonance imaging (fMRI) has grown very rapidly since the first description of the technique in the early 1990s. Most published studies have utilized data analysis methods based on voxel-wise application of general linear models (GLM). On the other hand, temporal clustering analysis (TCA) focuses on the identification of relationships between cortical areas by measuring temporal common properties. In its most general form, TCA is sensitive to the low signal-to-noise ratio of BOLD and is dependent on subjective choices of filtering parameters. In this paper, we introduce a method for wavelet-based clustering of time-series data and show that it may be useful in data sets with low signal-to-noise ratios, allowing the automatic selection of the optimum number of clusters. We also provide examples of the technique applied to simulated and real fMRI datasets.


Assuntos
Algoritmos , Análise por Conglomerados , Modelos Lineares , Imageamento por Ressonância Magnética , Processamento de Sinais Assistido por Computador , Estimulação Acústica/métodos , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Mapeamento Encefálico , Emoções/fisiologia , Humanos , Estimulação Luminosa/métodos , Fatores de Tempo
14.
Eur Psychiatry ; 21(5): 291-9, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16406503

RESUMO

Several studies have independently suggested that patients with schizophrenia are more likely to have an enlarged cavum septum pellucidum (CSP) and an absent adhesio interthalamica (AI), respectively. However, neither finding has been consistently replicated and it is unclear whether there is an association between these two midline brain abnormalities. Thus, we compared the prevalence of absent AI and the prevalence, size and volume of CSP in 38 patients with schizophrenia and 38 healthy controls using magnetic resonance imaging (MRI). There were no between group differences in the presence or volume of CSP; however, an enlarged CSP was commoner among patients than controls. There was also a positive correlation between CSP ratings and volumes. No differences in the presence or absence of the AI were found between patients and controls; however, an absent AI was commoner in male patients with schizophrenia than females. There was absolutely no overlap between the presence of a large CSP and an absence of AI. In conclusion, our findings are in line with several case series and other MRI investigations that have shown a higher incidence of putatively developmental brain abnormalities in patients with schizophrenia, particularly in males, and support the neurodevelopmental model of this disorder.


Assuntos
Imageamento por Ressonância Magnética , Esquizofrenia/diagnóstico , Septo Pelúcido/anormalidades , Septo Pelúcido/patologia , Tálamo/anormalidades , Tálamo/patologia , Adulto , Comorbidade , Estudos Transversais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Esquizofrenia/patologia , Caracteres Sexuais
15.
Hum Brain Mapp ; 26(1): 44-53, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15884023

RESUMO

Auditory hallucinations are thought to arise through the misidentification of self-generated verbal material as alien. The neural mechanisms that normally mediate the differentiation of self-generated from nonself speech are unclear. We investigated this in healthy volunteers using functional MRI. Eleven healthy volunteers were scanned whilst listening to a series of prerecorded words. The source (self/nonself) and acoustic quality (undistorted/distorted) of the speech was varied across trials. Participants indicated whether the words were spoken in their own or another person's voice via a button press. Listening to self-generated words was associated with more activation in the left inferior frontal and right anterior cingulate cortex than words in another person's voice, which was associated with greater engagement of the lateral temporal cortex bilaterally. Listening to distorted speech was associated with activation in the inferior frontal and anterior cingulate cortex. There was an interaction between the effects of source of speech and distortion on activation in the left temporal cortex. In the presence of distortion participants were more likely to misidentify their voice as that of another. This misattribution of self-generated speech was associated with reduced engagement of the cingulate and prefrontal cortices. The evaluation of auditory speech involves a network including the inferior frontal, anterior cingulate, and lateral temporal cortex. The degree to which different areas within this network are engaged varies with the source and acoustic quality of the speech. Accurate identification of one's own speech appears to depend on cingulate and prefrontal activity.


Assuntos
Mapeamento Encefálico , Percepção da Fala/fisiologia , Fala/fisiologia , Estimulação Acústica , Adulto , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino
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