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1.
Neurol Sci ; 43(9): 5313-5322, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35739332

RESUMO

People with Parkinson's disease (PD) experience functional limitations early in the progression of the disease, showing, among other cognitive deficits, difficulties in mathematical abilities. The neural correlates of such abilities have been scarcely investigated in PD, and it is not known whether patients may exhibit difficulties only in formal numerical tasks (e.g., mental multiplications), or also in everyday activities involving numbers (i.e., informal numerical abilities such as time estimates). The present study investigated formal and informal numerical abilities in PD patients and explored their relationship with cortical and subcortical brain volume. We examined patients with PD and mild cognitive impairment (PD-MCI) and age-matched healthy controls (HCs) using the numerical activities of daily living (NADL) battery, assessing both scholastic numerical abilities (formal test), and the ability to use numbers in everyday life (informal test). We compared NADL performances in both groups. Within the PD group, we investigated the association between NADL and cortical and subcortical volumes using multiple linear regressions. The correlation with other cognitive tests was also explored. PD-MCI performed worse than HC in the formal NADL test. In PD-MCI patients, brain-behavior correlations showed two distinct patterns: cortical volumes correlated positively, while striatal volumes correlated negatively with NADL formal tasks. Both formal and informal tests correlated with measures of cognitive functioning. Our results suggest specific impairments in formal numerical abilities in PD-MCI, but not in everyday activities. While cortical atrophy is associated with worse performance, the negative correlations with subcortical regions suggest that their activation may reflect potential compensatory mechanisms.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Atividades Cotidianas/psicologia , Disfunção Cognitiva/fisiopatologia , Humanos , Conceitos Matemáticos , Testes Neuropsicológicos , Doença de Parkinson/psicologia
2.
CNS Spectr ; 22(5): 415-426, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28181901

RESUMO

OBJECTIVE: Our aim was to perform an updated systematic review and meta-analysis on the efficacy and safety of adjunctive minocycline as a treatment of schizophrenia. METHODS: We conducted a PubMed/Scopus database search from inception to 3 February 2016 for randomized, placebo-controlled trials (RCTs), open non-randomized studies, and case reports/series evaluating minocycline in patients with schizophrenia. Random-effects meta-analysis of positive, negative, depressive, and cognitive symptom rating scales, discontinuation and adverse effects rates calculating standardized mean difference (SMD), and risk ratios±95% confidence intervals (CI 95%) were calculated. RESULTS: Six RCTs were eligible (minocycline n=215, placebo n=198) that demonstrated minocycline's superiority versus placebo for reducing endpoint Positive and Negative Syndrome Scale (PANSS) total scores (SMD=-0.59; CI 95%=[1.15, -0.03]; p=0.04), negative (SMD=-0.76; CI 95%=[-1.21, -0.31]; p=0.001); general subscale scores (SMD=-0.44; CI 95%=[-0.88, -0.00]; p=0.05), Clinical Global Impressions scores (SMD=-0.50; CI 95%=[-0.78, -0.22]; p<0.001); and executive functioning (SMD=0.22; CI 95%=[0.01, 0.44]; p=0.04). Endpoint PANSS positive symptom scores (p=0.13), depression rating scale scores (p=0.43), attention (p=0.47), memory (p=0.52), and motor speed processing (p=0.50) did not significantly differ from placebo, before execution of a trim-and-fill procedure. Minocycline did not differ compared to placebo on all-cause discontinuation (p=0.56), discontinuation due to inefficacy (p=0.99), and intolerability (p=0.51), and due to death (p=0.32). Data from one open-label study (N=22) and three case series (N=6) were consistent with the metaanalytic results. CONCLUSIONS: Minocycline appears to be an effective adjunctive treatment option in schizophrenia, improving multiple relevant disease dimensions. Moreover, minocycline has an acceptable safety and tolerability profile. However, more methodologically sound and larger RCTs remain necessary to confirm and extend these results.


Assuntos
Antibacterianos/uso terapêutico , Antipsicóticos/uso terapêutico , Minociclina/uso terapêutico , Esquizofrenia/tratamento farmacológico , Antibacterianos/efeitos adversos , Antipsicóticos/efeitos adversos , Humanos , Minociclina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Mov Disord ; 30(5): 688-95, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25649923

RESUMO

Previous functional neuroimaging studies in Parkinson's disease (PD) patients with impulse control disorders (ICDs) demonstrated dysfunction of the reward network, although the extent of anatomical changes is unclear. The aim of this study was to measure brain cortical thickness and subcortical volumes, and to assess their relationship with presence and severity of symptoms, in PD patients with and without ICDs. We studied 110 PD patients (N=58 with ICDs) and 33 healthy controls (all negative for ICDs) who underwent an extensive neurological, neuropsychological, and behavioral assessment as well as structural 1.5 Tesla magnetic resonance imaging (MRI). Between-group differences in brain cortical thickness and subcortical volumes, assessed with the FreeSurfer 5.1 tool, were analyzed. In patients with ICDs, we found significant cortical thinning in fronto-striatal circuitry, specifically in the right superior orbitofrontal, left rostral middle frontal, bilateral caudal middle frontal region, and corpus callosum, as well as volume reduction in the right accumbens and increase in the left amygdala. Finally, we observed a positive association relationship between severity of impulsive symptoms and left rostral middle frontal, inferior parietal, and supramarginal areas. These results support the involvement of both reward and response inhibition networks in PD patients with ICDs. Moreover, their severity is associated with alterations in brain regions linked with reward and top-down control networks. Increased understanding of the mechanisms underlying impulsive and compulsive behaviors might help improve therapeutic strategies for these important disorders.


Assuntos
Córtex Cerebral/patologia , Transtornos Disruptivos, de Controle do Impulso e da Conduta/complicações , Transtornos Disruptivos, de Controle do Impulso e da Conduta/patologia , Doença de Parkinson/complicações , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
4.
Neurol Sci ; 35(1): 73-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24052451

RESUMO

Hyperhomocysteinemia is a risk factor for Parkinson's disease (PD) and may result from genetic mutations or/and environmental factors. 5,10-methylenetetrahydrofolate reductase (MTHFR) is a folate-dependent enzyme that catalyzed remethylation of homocysteine (Hcy) and the MTHFR C677T polymorphism makes the MTHFR enzyme thermolabile causing hyperhomocysteinemia. In this study we analyzed whether two functional polymorphisms of MTHFR gene, A1298C and C677T, affect age of onset in PD. We enrolled 120 patients with sporadic PD. Patients were divided into three groups based on MTHFR C677T polymorphisms: (a) homozygotes wild type (CC) (b) heterozygotes (CT) and (c) homozygotes carriers of mutation (TT). MTHFR SNPs were analyzed using High-Resolution Melt analysis and ANOVA was performed to assess whether polymorphisms of MTHFR gene could influence age of onset. The MTHFR A1298C polymorphism had no effect on PD age at onset (p = 1.0) while there was a significant association with MTHFR C677T (p = 0.019 Bonferroni-adjusted post hoc) showing an earlier onset in CC as compared with TT. (p = 0.024). No differences were found for vascular load assessed with magnetic resonance imaging, pharmacological therapy and cognitive state for two MTHFR SNPs. Our results suggest a possible association of MTHFR C677T with age at onset of PD and may have important implications regarding the role of MTHFR.


Assuntos
Predisposição Genética para Doença/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único , Idade de Início , Idoso , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
J Neural Transm (Vienna) ; 120(4): 627-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23483334

RESUMO

Prevalence of mild cognitive impairment (MCI) in Parkinson's disease (PD) is variable likely due to methodological differences in classification criteria and lack of consensus about neuropsychological tests used for cognitive profiling. The main objective of our study was to identify the most suitable neuropsychological tests and determine their screening and diagnostic cutoff scores for PD-MCI. A series of 104 consecutive PD patients performed an extensive neuropsychological evaluation. Individual test values were converted into Z-scores using relative published normative data. According to published criteria, PD patients were categorized as PD-CNT (PD without cognitive impairment), PD-MCI (patients performing -1.5 SDs below the mean score in at least one cognitive domain), and PDD. We used receiver operating characteristic (ROC) curves and K-means clustering analyses to calculate the best discriminating power of each neuropsychological tests in detecting PD-MCI. PD patients were categorized as follows: 55 PD-CNT (53 %), 34 PD-MCI (33 %), and 15 PDD (14 %). PD-MCI had lower education, longer disease duration and greater frequency of hallucinations than PD-CNT. We found that only the Trail Making test, Rey-Osterrieth Complex Figure Test (ROCF) copy, Frontal Assessment Battery (FAB), Digit Span Backward, and Rey's word auditory verbal learning test (RVLT) immediate recall reached significant screening and diagnostic validity in predicting PD-MCI (AUC 0.705-0.795) with cutoff scores calculated by ROC analyses lying within normal range for normative data. Specific neuropsychological tests covering verbal memory, attention/set-shifting, and visual-spatial deficits are the best predictors of MCI in PD if valid cutoff scores are used. These results have consequences for cognitive diagnosis and potentially in establishing the rate of PD cognitive decline.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva/diagnóstico , Rememoração Mental/fisiologia , Doença de Parkinson/complicações , Aprendizagem Verbal/fisiologia , Idoso , Atenção/fisiologia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/psicologia , Função Executiva/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/psicologia
6.
Liver Int ; 33(2): 203-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23173839

RESUMO

BACKGROUND: Impaired sleep quality and daytime sleepiness have been described in patients with primary biliary cirrhosis (PBC). However, no information is available on their sleep timing/diurnal preference. AIMS: To evaluate such variables and determine their relationship with sleep quality, fatigue, pruritus and quality of life. METHODS: Seventy-four patients with PBC (58 ± 12 years), 79 healthy volunteers (56 ± 8 years) and 60 patients with cirrhosis (58 ± 12 years) underwent formal assessment of sleep quality/timing, diurnal preference and daytime sleepiness. Patients with PBC also underwent assessment of fatigue, quality of life and the daytime course of sleepiness/pruritus. RESULTS: Sleep timing was significantly delayed in both patients with PBC and with cirrhosis, compared to healthy volunteers (sleep onset time: 23:18 ± 01:00 vs. 23:30 ± 01:00 vs. 22:54 ± 00:54 hours, respectively; P < 0.05). In patients with PBC, delayed sleep timing was associated with impaired sleep quality (P < 0.05). Sleepiness showed a physiological daily rhythm, with early afternoon/evening peaks. Pruritus was absent in the morning and increased over the afternoon/evening hours. Both the daytime course of pruritus and sleepiness changed in relation to diurnal preference. Patients with PBC and significant pruritus (upper quartile) had prolonged sleep latency (39 ± 37 vs. 21 ± 23 min, P = 0.05) and earlier wake-up times (5.9 ± 0.8 vs. 6.7 ± 0.9 min, P < 0.05). Significant correlations were observed between sleep timing and quality of life. CONCLUSIONS: Patients with PBC exhibited a delay in sleep timing that was associated with impaired sleep quality/quality of life. In addition, an interplay was observed between diurnal preference and the daytime course of pruritus/sleepiness.


Assuntos
Fadiga/fisiopatologia , Cirrose Hepática Biliar/complicações , Prurido/fisiopatologia , Transtornos do Sono do Ritmo Circadiano/patologia , Idoso , Fadiga/etiologia , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Prurido/etiologia , Transtornos do Sono do Ritmo Circadiano/etiologia , Inquéritos e Questionários
7.
Sci Rep ; 13(1): 10389, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37369744

RESUMO

Resting state fMRI has been used in many studies to investigate the impact of brain tumours on functional connectivity (FC). However, these studies have so far assumed that FC is stationary, disregarding the fact that the brain fluctuates over dynamic states. Here we utilised resting state fMRI data from 33 patients with high-grade gliomas and 33 healthy controls to examine the dynamic interplay between resting-state networks and to gain insights into the impact of brain tumours on functional dynamics. By employing Hidden Markov Models, we demonstrated that functional dynamics persist even in the presence of a high-grade glioma, and that patients exhibited a global decrease of connections strength, as well as of network segregation. Furthermore, through a multivariate analysis, we demonstrated that patients' cognitive scores are highly predictive of pathological dynamics, thus supporting our hypothesis that functional dynamics could serve as valuable biomarkers for better understanding the traits of high-grade gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Vias Neurais , Encéfalo , Mapeamento Encefálico , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética
8.
Cortex ; 166: 33-42, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37295236

RESUMO

The Oxford Cognitive Screen (OCS) was developed to measure cognitive impairment in stroke. Here, we test if the OCS administered acutely in stroke patients provides useful information in predicting long-term functional outcome. A group of first-time stroke patients (n = 74) underwent an acute behavioral assessment comprising the OCS and the NIHSS within one-week post-stroke. Functional outcome was evaluated using the Stroke Impact Scale 3.0 (SIS 3.0) and the Geriatric Depression Scale (GDS) at 6 and 12-months post-stroke. We compared the predictive ability of the OCS and NIHSS, separately or in combination, to predict different domains of behavioral impairment at a chronic evaluation. The OCS accounted for 61% of variance of SIS physical domain, 61% of memory domain, 79% of language domain, 70% of participation domain and 70% of recovery domain. The OCS accounted for a greater percentage of outcome variance than demographics and NIHSS. The most informative predictive model included the combination of demographics, OCS and NIHSS data. The OCS, performed early after stroke, is a strong independent predictor of long-term functional outcome and significantly improves the prediction of outcome when considered alongside the NIHSS and demographics.


Assuntos
Transtornos Cognitivos , Disfunção Cognitiva , Acidente Vascular Cerebral , Humanos , Idoso , Transtornos Cognitivos/psicologia , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/psicologia , Disfunção Cognitiva/diagnóstico , Cognição
9.
Front Neurol ; 14: 1175576, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37409023

RESUMO

Background: Resting-state functional-MRI studies identified several cortical gray matter functional networks (GMNs) and white matter functional networks (WMNs) with precise anatomical localization. Here, we aimed at describing the relationships between brain's functional topological organization and glioblastoma (GBM) location. Furthermore, we assessed whether GBM distribution across these networks was associated with overall survival (OS). Materials and methods: We included patients with histopathological diagnosis of IDH-wildtype GBM, presurgical MRI and survival data. For each patient, we recorded clinical-prognostic variables. GBM core and edema were segmented and normalized to a standard space. Pre-existing functional connectivity-based atlases were used to define network parcellations: 17 GMNs and 12 WMNs were considered in particular. We computed the percentage of lesion overlap with GMNs and WMNs, both for core and edema. Differences between overlap percentages were assessed through descriptive statistics, ANOVA, post-hoc tests, Pearson's correlation tests and canonical correlations. Multiple linear and non-linear regression tests were employed to explore relationships with OS. Results: 99 patients were included (70 males, mean age 62 years). The most involved GMNs included ventral somatomotor, salient ventral attention and default-mode networks; the most involved WMNs were ventral frontoparietal tracts, deep frontal white matter, and superior longitudinal fasciculus system. Superior longitudinal fasciculus system and dorsal frontoparietal tracts were significantly more included in the edema (p < 0.001). 5 main patterns of GBM core distribution across functional networks were found, while edema localization was less classifiable. ANOVA showed significant differences between mean overlap percentages, separately for GMNs and WMNs (p-values<0.0001). Core-N12 overlap predicts higher OS, although its inclusion does not increase the explained OS variance. Discussion and conclusion: Both GBM core and edema preferentially overlap with specific GMNs and WMNs, especially associative networks, and GBM core follows five main distribution patterns. Some inter-related GMNs and WMNs were co-lesioned by GBM, suggesting that GBM distribution is not independent of the brain's structural and functional organization. Although the involvement of ventral frontoparietal tracts (N12) seems to have some role in predicting survival, network-topology information is overall scarcely informative about OS. fMRI-based approaches may more effectively demonstrate the effects of GBM on brain networks and survival.

10.
Neuroimage Clin ; 40: 103518, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37778195

RESUMO

INTRODUCTION: Neuropsychological studies infer brain-behavior relationships from focal lesions like stroke and tumors. However, these pathologies impair brain function through different mechanisms even when they occur at the same brain's location. The aim of this study was to compare the profile of cognitive impairment in patients with brain tumors vs. stroke and examine the correlation with lesion location in each pathology. METHODS: Patients with first time stroke (n = 77) or newly diagnosed brain tumors (n = 76) were assessed with a neuropsychological battery. Their lesions were mapped with MRI scans. Test scores were analyzed using principal component analysis (PCA) to measure their correlation, and logistic regression to examine differences between pathologies. Next, with ridge regression we examined whether lesion features (location, volume) were associated with behavioral performance. RESULTS: The PCA showed a similar cognitive impairment profile in tumors and strokes with three principal components (PCs) accounting for about half of the individual variance. PC1 loaded on language, verbal memory, and executive/working memory; PC2 loaded on general performance, visuo-spatial attention and memory, and executive functions; and, PC3 loaded on calculation, reading and visuo-spatial attention. The average lesion distribution was different, and lesion location was correlated with cognitive deficits only in stroke. Logistic regression found language and calculation more affected in stroke, and verbal memory and verbal fluency more affected in tumors. CONCLUSIONS: A similar low dimensional set of behavioral impairments was found both in stroke and brain tumors, even though each pathology caused some specific deficits in different domains. The lesion distribution was different for stroke and tumors and correlated with behavioral impairment only in stroke.


Assuntos
Neoplasias Encefálicas , Disfunção Cognitiva , Acidente Vascular Cerebral , Humanos , Função Executiva , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/complicações , Encéfalo , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Memória de Curto Prazo , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Testes Neuropsicológicos , Imageamento por Ressonância Magnética
11.
Brain Sci ; 13(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36831777

RESUMO

Background. In deep-seated brain tumors, adequate preoperative planning is mandatory to assess the best surgical corridor to obtain maximal safe resection. Functional diffusor tensor imaging (DTI) tractography based on navigated transcranial magnetic stimulation (nTMS) motor mapping has proven to be a valid preoperative examination method in adults. The aim of this paper is to present the application of nTMS and functional DTI tractography in a series of pediatric diencephalic tumors. Material and methods. Three patients affected by thalamic (one) and thalamopeduncular tumor (two) were successfully examined with nTMS motor mapping and DTI tractography between October 2020 and October 2021 (F:M 3:0, mean age 12 years ± 0.8). Cortical representation of leg, hand and mouth were determined in the affected hemisphere and the positive stimulation spots were set as seeds point for tractography. Results. Mapping of the motor cortex and tracts reconstruction for leg and hand were successful in all patients, while facial function was properly mapped in one patient only. In all cases, the procedure was well tolerated and no adverse events were recorded. Spatial relationships between tumor and functional tissue guided the surgical planning. Extent of the resection varied from 96.1% to 100% with a postoperative new motor deficit in one patient. Conclusions. nTMS and DTI fiber tracking is a feasible, effective and well-tolerated method to identify motor pathway in deep-seated lesion in pediatric population.

12.
Neuroimage Clin ; 34: 102968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35220105

RESUMO

Diffusion-based biophysical models have been used in several recent works to study the microenvironment of brain tumours. While the pathophysiological interpretation of the parameters of these models remains unclear, their use as signal representations may yield useful biomarkers for monitoring the treatment and the progression of this complex and heterogeneous disease. Up to now, however, no study was devoted to assessing the mathematical stability of these approaches in cancerous brain regions. To this end, we analyzed in 11 brain tumour patients the fitting results of two microstructure models (Neurite Orientation Dispersion and Density Imaging and the Spherical Mean Technique) and of a signal representation (Diffusion Kurtosis Imaging) to compare the reliability of their parameter estimates in the healthy brain and in the tumoral lesion. The framework of our between-tissue analysis included the computation of 1) the residual sum of squares as a goodness-of-fit measure 2) the standard deviation of the models' derived metrics and 3) models' sensitivity functions to analyze the suitability of the employed protocol for parameter estimation in the different microenvironments. Our results revealed no issues concerning the fitting of the models in the tumoral lesion, with similar goodness of fit and parameter precisions occurring in normal appearing and pathological tissues. Lastly, with the aim of highlight possible biomarkers, in our analysis we briefly discuss the correlation between the metrics of the three techniques, identifying groups of indices which are significantly collinear in all tissues and thus provide no additional information when jointly used in data-driven analyses.


Assuntos
Neoplasias Encefálicas , Imagem de Difusão por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Humanos , Reprodutibilidade dos Testes , Microambiente Tumoral
13.
Neuropsychologia ; 169: 108187, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35218790

RESUMO

Though the assessment of cognitive functions is proven to be a reliable prognostic indicator in patients with brain tumors, some of these functions, such as cognitive control, are still rarely investigated. The objective of this study was to examine proactive and reactive control functions in patients with focal brain tumors and to identify lesioned brain areas more at "risk" for developing impairment of these functions. To this end, a group of twenty-two patients, candidate to surgery, were tested with an AX-CPT task and a Stroop task, along with a clinical neuropsychological assessment, and their performance was compared to that of a well-matched healthy control group. Although overall accuracy and response times were similar for patients and control groups, the patient group failed more on the BX trials of the AX-CPT task and on the incongruent trials of the Stroop task, specifically. Behavioral results were associated with the damaged brain areas, mostly distributed in right frontal regions, by means of a lesion-symptom mapping multivariate approach. This analysis showed that a white matter cluster in the right prefrontal area was associated with lower d'-context values on the AX-CPT, which reflected the fact that these patients rely more on later information (reactive processes) to respond to unexpected and conflicting stimuli, than on earlier contextual cues (proactive processes). Taken together, these results suggest that patients with brain tumors present an imbalance between proactive and reactive control strategies in high interfering conditions, in association with right prefrontal white matter lesions.


Assuntos
Neoplasias Encefálicas , Disfunção Cognitiva , Mapeamento Encefálico , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico por imagem , Cognição/fisiologia , Humanos , Córtex Pré-Frontal/fisiologia , Tempo de Reação/fisiologia
14.
Brain Commun ; 4(2): fcac082, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35474856

RESUMO

Assessment of impaired/preserved cortical regions in brain tumours is typically performed via intraoperative direct brain stimulation of eloquent areas or task-based functional MRI. One main limitation is that they overlook distal brain regions or networks that could be functionally impaired by the tumour. This study aims (i) to investigate the impact of brain tumours on the cortical synchronization of brain networks measured with resting-state functional magnetic resonance imaging (resting-state networks) both near the lesion and remotely and (ii) to test whether potential changes in resting-state networks correlate with cognitive status. The sample included 24 glioma patients (mean age: 58.1 ± 16.4 years) with different pathological staging. We developed a new method for single subject localization of resting-state networks abnormalities. First, we derived the spatial pattern of the main resting-state networks by means of the group-guided independent component analysis. This was informed by a high-resolution resting-state networks template derived from an independent sample of healthy controls. Second, we developed a spatial similarity index to measure differences in network topography and strength between healthy controls and individual brain tumour patients. Next, we investigated the spatial relationship between altered networks and tumour location. Finally, multivariate analyses related cognitive scores across multiple cognitive domains (attention, language, memory, decision making) with patterns of multi-network abnormality. We found that brain gliomas cause broad alterations of resting-state networks topography that occurred mainly in structurally normal regions outside the tumour and oedema region. Cortical regions near the tumour often showed normal synchronization. Finally, multi-network abnormalities predicted attention deficits. Overall, we present a novel method for the functional localization of resting-state networks abnormalities in individual glioma patients. These abnormalities partially explain cognitive disabilities and shall be carefully navigated during surgery.

15.
Brain Struct Funct ; 227(9): 3109-3120, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35503481

RESUMO

Gliomas are amongst the most common primary brain tumours in adults and are often associated with poor prognosis. Understanding the extent of white matter (WM) which is affected outside the tumoral lesion may be of paramount importance to explain cognitive deficits and the clinical progression of the disease. To this end, we explored both direct (i.e., tractography based) and indirect (i.e., atlas-based) approaches to quantifying WM structural disconnections in a cohort of 44 high- and low-grade glioma patients. While these methodologies have recently gained popularity in the context of stroke and other pathologies, to our knowledge, this is the first time they are applied in patients with brain tumours. More specifically, in this work, we present a quantitative comparison of the disconnection maps provided by the two methodologies by applying well-known metrics of spatial similarity, extension, and correlation. Given the important role the oedematous tissue plays in the physiopathology of tumours, we performed these analyses both by including and excluding it in the definition of the tumoral lesion. This was done to investigate possible differences determined by this choice. We found that direct and indirect approaches offer two distinct pictures of structural disconnections in patients affected by brain gliomas, presenting key differences in several regions of the brain. Following the outcomes of our analysis, we eventually discuss the strengths and pitfalls of these two approaches when applied in this critical field.


Assuntos
Neoplasias Encefálicas , Glioma , Substância Branca , Adulto , Humanos , Glioma/diagnóstico por imagem , Glioma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
16.
Cortex ; 144: 56-69, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34649006

RESUMO

"Macrographia", a relatively rare symptom generally following cerebellar diseases, consists of an abnormally large handwriting. The case reported in the present investigation shows several outstanding features. First, it is of the progressive variety, letters increase in size as one goes through the word towards the lower-right portion of space. Moreover, it is limited to one allographic variety, that is, block letters. This phenomenon is previously unreported, all allographic varieties being usually equally affected. Finally, no prominent cerebellar or basal ganglia abnormality could be demonstrated with structural MRI or PET. From a cognitive point of view, a peculiar combination of spatial attention, executive function and working memory deficits is proposed to account for the progressive misalignment and elongation of individual letters when specifically writing in block prints. From an anatomical perspective, the pattern of multifocal lesions, encompassing multiple cortical areas in both hemispheres and the corpus callosum, may support this multi-componential interpretation of the reported phenomenon.


Assuntos
Agrafia , Escrita Manual , Agrafia/diagnóstico por imagem , Atenção , Função Executiva , Humanos , Imageamento por Ressonância Magnética , Transtornos da Memória , Redação
17.
Brain Commun ; 3(2): fcab119, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34136813

RESUMO

Neurological deficits following stroke are traditionally described as syndromes related to damage of a specific area or vascular territory. Recent studies indicate that, at the population level, post-stroke neurological impairments cluster in three sets of correlated deficits across different behavioural domains. To examine the reproducibility and specificity of this structure, we prospectively studied first-time stroke patients (n = 237) using a bedside, clinically applicable, neuropsychological assessment and compared the behavioural and anatomical results with those obtained from a different prospective cohort studied with an extensive neuropsychological battery. The behavioural assessment at 1-week post-stroke included the Oxford Cognitive Screen and the National Institutes of Health Stroke Scale. A principal component analysis was used to reduce variables and describe behavioural variance across patients. Lesions were manually segmented on structural scans. The relationship between anatomy and behaviour was analysed using multivariate regression models. Three principal components explained ≈50% of the behavioural variance across subjects. PC1 loaded on language, calculation, praxis, right side neglect and memory deficits; PC2 loaded on left motor, visual and spatial neglect deficits; PC3 loaded on right motor deficits. These components matched those obtained with a more extensive battery. The underlying lesion anatomy was also similar. Neurological deficits following stroke are correlated in a low-dimensional structure of impairment, related neither to the damage of a specific area or vascular territory. Rather they reflect widespread network impairment caused by focal lesions. These factors showed consistency across different populations, neurobehavioural batteries and, most importantly, can be described using a combination of clinically applicable batteries (National Institutes of Health Stroke Scale and Oxford Cognitive Screen). They represent robust behavioural biomarkers for future stroke population studies.

18.
Brain Sci ; 11(5)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33924964

RESUMO

Awake surgery and intraoperative neuromonitoring represent the gold standard for surgery of lesion located in language-eloquent areas of the dominant hemisphere, enabling the maximal safe resection while preserving language function. Nevertheless, this functional mapping is invasive; it can be executed only during surgery and in selected patients. Moreover, the number of neuro-oncological bilingual patients is constantly growing, and performing awake surgery in this group of patients can be difficult. In this scenario, the application of accurate, repeatable and non-invasive preoperative mapping procedures is needed, in order to define the anatomical distribution of both languages. Repetitive navigated transcranial magnetic stimulation (rnTMS) associated with functional subcortical fiber tracking (nTMS-based DTI-FT) represents a promising and comprehensive mapping tool to display language pathway and function reorganization in neurosurgical patients. Herein we report a case of a bilingual patient affected by brain tumor in the left temporal lobe, who underwent rnTMS mapping for both languages (Romanian and Italian), disclosing the true eloquence of the anterior part of the lesion in both tests. After surgery, language abilities were intact at follow-up in both languages. This case represents a preliminary application of nTMS-based DTI-FT in neurosurgery for brain tumor in eloquent areas in a bilingual patient.

19.
J Am Geriatr Soc ; 66(2): 350-356, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29322488

RESUMO

OBJECTIVES: To investigate dysfunction in fine motor skills in a cohort of older Italian adults, identifying their prevalence and usefulness as indicators and predictors of cognitive impairment. DESIGN: Population-based longitudinal study with mean follow-up of 4.4 years. SETTING: Community. PARTICIPANTS: Older men and women enrolled in the Progetto Veneto Anziani (Pro.V.A.) (N = 2,361); 1,243 subjects who were cognitively intact at baseline were selected for longitudinal analyses. MEASUREMENTS: Fine motor skills were assessed by measuring the time needed to successfully complete two functional tasks: putting on a shirt and a manual dexterity task. Cognitive impairment was defined as a Mini-Mental State Examination (MMSE) score less than 24. RESULTS: On simple correlation, baseline MMSE score was significantly associated with the manual dexterity task (correlation coefficient (r) = -0.25, P < .001) and time needed to put on a shirt (r = -0.29, P < .001). Over the study period, changes in time needed to perform the fine motor tasks were significantly associated with changes in MMSE (putting on a shirt: ß = 0.083, P = .003; manual dexterity task: ß = 0.098, P < .001). Logistic regression analyses confirmed that worse results on tasks were associated with cognitive impairment at baseline (odds ratio (OR) = 2.47, 95% confidence interval (CI) = 1.74-3.50, for the fourth quartile of time needed to put on a shirt; OR = 1.98, 95% CI = 1.42-2.76, for the fourth manual dexterity task quartile) and greater risk of cognitive impairment developing during follow-up (OR = 4.38, 95% CI = 2.46-7.80, for the fourth quartile of time needed to put on a shirt; OR = 2.20, 95% CI = 1.30-3.72, for the fourth manual dexterity task quartile). CONCLUSIONS: Difficulties with fine motor skills are common in older adults, and assessing them may help to identify early signs of dementia, subjects at high risk to develop cognitive decline, and individuals who can be referred to specialists.


Assuntos
Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Destreza Motora/fisiologia , Idoso , Estudos de Coortes , Feminino , Humanos , Itália/epidemiologia , Estudos Longitudinais , Masculino , Prevalência , Fatores de Tempo
20.
Neurosci Biobehav Rev ; 72: 87-94, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27890688

RESUMO

Whilst obesity is associated with a higher risk of cognitive impairment, the influence of weight loss on cognitive function in obese/overweight people is equivocal. We conducted a meta-analysis of randomized controlled trials (RCTs) and longitudinal studies evaluating the influence of voluntary weight loss on cognitive function in obese/overweight individuals. Articles were acquired from a systematic search of major databases from inception till 01/2016. A random effect meta-analysis of weight loss interventions (diet, physical activity, bariatric surgery) on different cognitive domains (memory, attention, executive functions, language and motor speed) was conducted. Twenty studies (13 longitudinal studies=551 participants; 7 RCTs=328 treated vs. 140 controls) were included. Weight loss was associated with a significant improvement in attention and memory in both longitudinal studies and RCTs, whereas executive function and language improved in longitudinal and RCT studies, respectively. In conclusion, intentional weight loss in obese/overweight people is associated with improvements in performance across various cognitive domains. Future adequately powered RCTs are required to confirm/refute these findings.


Assuntos
Cognição , Obesidade , Sobrepeso , Exercício Físico , Humanos , Redução de Peso
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