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INTRODUCTION: Gaucher's disease (GD) is caused by biallelic mutations in the GBA1 gene, leading to reduced glucocerebrosidase (GCase) activity and substrate (glucosylceramide and glucosylsphingosine, GlcSph) accumulation. GBA1 variant carriers are at risk of Parkinson's disease (PD), but only those with biallelic mutations cross the threshold of GCase reduction, leading to substrate accumulation and GD. The link between GBA1 mutations, GD and PD is not fully understood. Here we aimed at reporting the results of a large PD population screening with dried blood spot tests for GD. METHODS: We measured GCase activity and GlcSph levels in 1344 PD patients with dried blood spot tests, and performed GBA1 genetic sequencing. RESULTS: While the GCase activity was reduced in GBA1-PD carriers compared to wild type PD, GlcSph was increased in GBA1-PD compared to GBA1-controls, regardless of the underlying type of GBA1 variant. 13.6 % and 0.4 % of PD patients had mono- or biallelic GBA1 mutations respectively. GCase deficiency, lipid accumulation and clinical manifestations of GD was detected in five PD patients with biallelic GBA1 mutations, of whom four had a risk combined with a GD causing variant. CONCLUSIONS: GlcSph appearing higher in PD may represent a reliable biomarker of the disease and deserves to be further investigated. This study highlights the importance of screening PD patients for possible underlying GD, which is a treatable condition that should not be missed. We diagnosed GD cases carrying a "risk" variant in one allele, which is an unprecedented finding deserving further investigation.
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Doença de Gaucher , Glucosilceramidase , Doença de Parkinson , Psicosina , Humanos , Glucosilceramidase/genética , Doença de Gaucher/genética , Doença de Gaucher/sangue , Doença de Parkinson/genética , Doença de Parkinson/sangue , Psicosina/análogos & derivados , Psicosina/sangue , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Mutação , Teste em Amostras de Sangue Seco , Adulto , Idoso de 80 Anos ou maisRESUMO
The prevention and treatment of frailty condition among multimorbid older adults, in community and hospital settings, is becoming a healthcare priority. Growing evidence suggests that a multidimensional approach could help not only in the early identification of older patients' needs but also in designing personalized preventive interventions. However, in clinical practice, the effectiveness of such interventions is limited by a lack of continuity of care and poor compliance of patients. The widespread diffusion of the information and communication technology (ICT) could offer an excellent way to implement and monitor multidimensional and personalized interventions for multimorbid older adults. In this scenario, the MULTIPLAT_AGE, is a network project involving five research centers with the main objective to supply multidimensional interventions targeted to cognitive, motor, pharmacological, and functional domains including ICT-based: i) transitional care model from the hospital to a protected home area; ii) automatic home-care system to improve activities of daily living; iii) program to improve appropriate drug prescription in nursing-home residents; iv) tele-rehabilitation program to reduce the risk of falls and v) cognitive stimulation delivered by remote in older adults with neurological disorders. Each project is linked to the others by employing a shared online platform, in a perspective of technological-supplied multicomponent interventions according to the concept of "aging in place" as the best solution for the treatment and healthcare of older people. Here we describe the general framework of the MULTIPLAT_AGE, and we examine every single project, pointing out innovative aspects, and discussing the expected results.
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Idoso Fragilizado , Fragilidade , Humanos , Idoso , Atividades Cotidianas , Vida Independente , ComunicaçãoRESUMO
BACKGROUND AND PURPOSE: Hormonal replacement therapy (HRT) is used for symptomatic treatment of menopause. Some evidence suggests a proconvulsant effect of estrogen and an anticonvulsant role of progesterone. Thus, the use of exogenous sex steroid hormones might influence the course of epilepsy in peri- and postmenopausal women with epilepsy (WWE). We conducted a systematic review on the impact of HRT on the frequency of seizures of WWE. METHODS: PubMed and Scopus were searched for articles published from inception until August 2022. Abstracts from the past 5 years from the European Academy of Neurology and European Epilepsy Congresses were also reviewed. Article reference lists were screened, and relevant articles were retrieved for consultation. Interventional and observational studies on WWE and animal models of estrogen deficiency were included. Critical appraisal was performed using the revised Cochrane risk-of-bias tool for randomized trials and ROBINS-E tool. RESULTS: Of 497 articles screened, 13 studies were included, including three human studies. One cross-sectional study showed a decrease in seizure frequency in WWE using combined HRT, a case-control study showed an increase in comparison with controls, and a randomized clinical trial found a dose-dependent increase in seizure frequency in women with focal epilepsy taking combined HRT. Ten studies addressing the impact of HRT in rat models were also included, which showed conflicting results. CONCLUSIONS: There is scarce evidence of the impact of HRT in WWE. Further studies should evaluate the harmful potential, and prospective registries are needed for monitoring this population.
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Epilepsia , Pós-Menopausa , Feminino , Humanos , Animais , Ratos , Estudos de Casos e Controles , Estudos Prospectivos , Estudos Transversais , Epilepsia/tratamento farmacológico , Convulsões/tratamento farmacológico , Estrogênios/farmacologia , Estrogênios/uso terapêutico , Hormônios Esteroides Gonadais/farmacologia , Hormônios Esteroides Gonadais/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Recently, a novel pathogenic variant in Annexin A1 protein (c.4G > A, p.Ala2Thr) has been identified in an Iranian consanguineous family with autosomal recessive parkinsonism. The deficiencies of ANXA1 could lead to extracellular SNCA accumulation, defects in intracellular signaling pathways and synaptic plasticity causing parkinsonism. The aim of this study was to identify rare ANXA1 variants in 95 early-onset PD patients from South Italy. Sequencing analysis of ANXA1 gene revealed only 2 synonymous variants in PD patients (rs1050305, rs149033255). Therefore, we conclude that the recently published ANXA1 mutation is not a common cause of EOPD in Southern Italy.
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Transtornos Parkinsonianos , Humanos , Idade de Início , Irã (Geográfico) , Itália , Mutação/genética , Transtornos Parkinsonianos/genéticaRESUMO
Sex and gender-based differences in epidemiology, clinical features and therapeutical responses are emerging in several movement disorders, even though they are still not widely recognized. In this chapter, we summarize the most relevant evidence concerning these differences in Parkinson's disease, essential tremor, dystonia and chorea. Indeed, both sex-related biological (hormonal levels fluctuations) and gender-related variables (socio-cultural and environmental factors) may differently impact symptoms manifestation and severity, phenotype and disease progression of movement disorders on men and women. Moreover, sex differences in treatment responses should be taken into account in any therapeutical planning. Physicians need to be aware of these major differences between men and women that will eventually have a major impact on better tailoring prevention, treatment, or even delaying progression of the most common movement disorders.
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Coreia , Distonia , Distúrbios Distônicos , Tremor Essencial , Transtornos dos Movimentos , Doença de Parkinson , Coreia/diagnóstico , Coreia/epidemiologia , Distonia/diagnóstico , Distonia/epidemiologia , Distonia/terapia , Tremor Essencial/epidemiologia , Tremor Essencial/terapia , Feminino , Humanos , Masculino , Doença de Parkinson/complicações , Doença de Parkinson/epidemiologia , Fatores SexuaisRESUMO
BACKGROUND: Neurological disorders pose a profound unmet medical need for which new solutions are urgently needed. The consideration of both biological (sex) and socio-cultural (gender) differences between men and women is necessary to identify more efficacious, safer and tailored treatments. Approaches for putting sex and gender medicine into practice have gathered momentum across Europe, but it is currently unclear to what extent they have been implemented in the field of neurology and neuroscience. METHODS: We mapped current activities in research, funding and education aimed at integrating sex and gender consideration in neuroscience and neurology in Europe. We examined and analyzed data gathered from (1) literature searches, (2) policy documents and reports by the European Commission and national funding agencies, (3) web-based searches, (4) "Web of Science", and (5) searches of project databases of funding agencies. An informative / non-systematic search was performed for sections on policies and funding, education, basic research, while a systematic literature and database review was conducted forquantitative analysis of research output and funded projects in terms of sex and gender analysis. RESULTS: Our mapping shows that there is a growing interest and attention towards sex and gender consideration in neurological fields, both from funding agencies and researchers. However, most activities, especially for education, are limited to the individual motivation of researchers and are not organically built within curricula and strategic research priorities. DISCUSSION: We recommend actions that might help increase the consideration of sex and gender specifically in the field of neuroscience and neurology.
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OBJECTIVE: Structural abnormalities in thalami and basal ganglia, in particular the globus pallidus (GP), are a neuroimaging hallmark of hereditary aceruloplasminemia (HA), yet few functional imaging data exit in HA carriers. This study investigated the iron-related structural and functional abnormalities in an Italian HA family. METHODS: Multimodal imaging was used including structural 3 T MRI, functional imaging (SPECT imaging with 123I-ioflupane (DAT-SPECT), cardiac 123I metaiodobenzylguanidine (123I-MIBG) scintigraphy, and 18F-fluorodeoxyglucose (18F-FDG)-PET imaging). In the proband, MRI and scintigraphic evaluations were performed at baseline, 2 and 4 years (structural imaging), and 2 years of follow-up period (functional imaging). RESULTS: We investigated two cousins carrying a novel splicing homozygous mutation in intron 6 (IVS6 + 1 G > A) of CP gene. Interestingly, MRI features in both subjects were characterized by marked iron accumulation in the thalami and basal ganglia nuclei, while GP was not affected. MRI performed in the proband at 2 and 4 years of follow-up confirmed progressive neurodegeneration of the thalami and basal ganglia without the involvement of GP. Functional imaging showed reduced putaminal DAT uptake in both cousins, whereas cardiac MIBG and FDG uptakes performed in the proband were normal. Longitudinal scintigraphic investigations did not show significant changes over the time. CONCLUSIONS: For HA carriers, our findings demonstrate that GP was spared by iron accumulation over the time. The nigrostriatal presynaptic dopaminergic system was damaged while the cardiac sympathetic system remained longitudinally preserved, thus expanding the imaging features of this rare inherited disorder.
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Distúrbios do Metabolismo do Ferro , Doenças Neurodegenerativas , 3-Iodobenzilguanidina , Ceruloplasmina/deficiência , Humanos , Distúrbios do Metabolismo do Ferro/diagnóstico por imagem , Distúrbios do Metabolismo do Ferro/genética , Imageamento por Ressonância Magnética , Imagem Multimodal , Mutação , Doenças Neurodegenerativas/diagnóstico por imagem , Doenças Neurodegenerativas/genética , Tomografia por Emissão de Pósitrons/métodos , Compostos RadiofarmacêuticosRESUMO
Introduction: Hyper-religiosity has been reported in patients affected by frontotemporal dementia (FTD) with asymmetrical, predominantly right-sided frontotemporal atrophy. Case report: We report a FTD patient carrying a double genetic variant (p.Cys139Arg and c.*78C > T) in the progranulin (GRN) gene who showed an unusual clinical phenotype characterized by hyper-religiosity behavior and visual hallucinations with exclusively religious content. Noteworthy, this patient exhibited a slow clinical and radiological rate of disease progression and a predominantly left-sided frontotemporal atrophy. Discussion and conclusion: The simultaneous presence of these GRN variants in our FTD patient with predominant atrophy in the left (dominant) hemisphere could determine the unusual phenotype with hyper-religiosity and visual hallucinations with exclusively religious content and influence the slow rate of disease progression.
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Esclerose Lateral Amiotrófica , Demência Frontotemporal , Doença de Pick , Demência Frontotemporal/complicações , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/genética , Alucinações/genética , Humanos , Mutação , Progranulinas/genéticaRESUMO
Deep grey nuclei of the human brain accumulate minerals both in aging and in several neurodegenerative diseases. Mineral deposition produces a shortening of the transverse relaxation time which causes hypointensity on magnetic resonance (MR) imaging. The physician often has difficulties in determining whether the incidental hypointensity of grey nuclei seen on MR images is related to aging or neurodegenerative pathology. We investigated the hypointensity patterns in globus pallidus, putamen, caudate nucleus, thalamus and dentate nucleus of 217 healthy subjects (ages, 20-79 years; men/women, 104/113) using 3T MR imaging. Hypointensity was detected more frequently in globus pallidus (35.5%) than in dentate nucleus (32.7%) and putamen (7.8%). A consistent effect of aging on hypointensity (p < 0.001) of these grey nuclei was evident. Putaminal hypointensity appeared only in elderly subjects whereas we did not find hypointensity in the caudate nucleus and thalamus of any subject. In conclusion, the evidence of hypointensity in the caudate nucleus and thalamus at any age or hypointensity in the putamen seen in young subjects should prompt the clinician to consider a neurodegenerative disease.
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Doenças Neurodegenerativas , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Feminino , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças Neurodegenerativas/diagnóstico por imagem , Putamen/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: Parkinson's Disease-related Psychosis (PDP) encompasses a spectrum of symptoms ranging from "minor" hallucinations to formed hallucinations and delusions. Notably, cognitive impairment has been recognized as the strongest risk factor for PDP. Several evidences suggest a possible role of cigarette smoking in both cognition and psychotic syndromes. OBJECTIVES: To evaluate the possible independent association between cigarette smoking and PDP in a large cohort of non-demented PD patients. METHODS: A cohort of non-demented PD patients was selected from the FRAGAMP study population. All participants underwent a standardised structured questionnaire to assess demographic, clinical and environmental exposure data. Clinical features were assessed using UPDRS, HY stage, AIMS, MMSE and Hamilton Rating Scale for Depression. Presence of psychotic symptoms was assessed using UPDRS-I.2 score. Diagnosis of PDP was made according to NINDS/NIMH criteria. RESULTS: Four hundred eighty-five non-demented PD patients were enrolled [292 men (60.2%); mean age ± SD 65.6 ± 9.8]. Among them, 28 (5.8%) had PDP. Multivariate analysis, adjusting by HY stage, MMSE and LED, shown an independent association between PDP and "nightmares-abnormal movements during sleep" and current smoking [adjOR 7.39 (95%CI 1.45-37.69; P-value 0.016)]. CONCLUSIONS: Our findings provide interesting insights about the possible role of current smoking in facilitating the occurrence of psychotic symptoms in PD.
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Fumar Cigarros , Doença de Parkinson , Transtornos Psicóticos , Estudos de Coortes , Alucinações , Humanos , Masculino , Doença de Parkinson/epidemiologia , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/etiologiaRESUMO
Background: Glucose alterations are associated with impaired cognition. The 1-h-post-load plasma glucose ≥155 mg/dl in non-diabetic subjects confers an increased risk of cardiovascular events and diabetes. This pilot study aimed to investigate whether the 1-h-post-load plasma glucose ≥155 mg/dl negatively affects the subcortical regions of the brain and the cognitive functions. Methods: We enrolled 32 non-diabetic subjects. Patients were divided into two groups based on 1-h- post-load plasma glucose value > or < 155 mg/dl: normal glucose tolerance (NGT) 1-h-high and NGT 1-h-low subjects. All subjects underwent 3 Tesla MRI and standard neuropsychological tests. Results: NGT 1-h-high subjects showed significantly lower values of both right (4.9 ± 0.9 vs. 5.1 ± 0.9 ml) and left (4.8 ± 1.1 vs. 5.1 ± 1.1 ml) hippocampal hemisphere volume, while right hemisphere hippocampal diffusivity was lower in the NGT 1-h-high group (10.0 ± 0.6 vs. 10.6 ± 0.5 10-4 mm2s-1). NGT 1-h-high subjects also showed a poorer memory performance. In particular, for both Rey Auditory Verbal Learning Task (RAVLT)-immediate-recall and Free and Cued Selective Reminding Test (FCSRT)-delayed total recall, we found lower cognitive test scores in the NGT-1 h-high group (26.5 ± 6.3 and 10.4 ± 0.3, respectively). Conclusions: One-hour-post-load hyperglycemia is associated with morpho-functional subcortical brain alterations and poor memory performance tests.
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BACKGROUND: Idiopathic normal pressure hydrocephalus and PSP share several clinical and radiological features, making differential diagnosis, at times, challenging. OBJECTIVES: To differentiate idiopathic normal pressure hydrocephalus from PSP using MR volumetric and linear measurements. METHODS: Twenty-seven idiopathic normal pressure hydrocephalus patients, 103 probable PSP patients, and 43 control subjects were consecutively enrolled. Automated ventricular volumetry was performed using Freesurfer 6 on MR T1 -weighted images. Linear measurements, such as callosal angle and a new measure, termed MR Hydrocephalic Index, were calculated on MR T1 -weighted images. Receiver operating characteristic analyses were used for differentiating between patient groups. Generalizability and reproducibility of the results were validated, dividing each participant group in two cohorts used as training and testing subsets. RESULTS: Ventricular volumes and linear measurements (callosal angle and Magnetic Resonance Hydrocephalic Index) revealed greater ventricular enlargement in patients with idiopathic normal pressure hydrocephalus than in PSP patients and controls. PSP patients had ventricular volume larger than controls. Automated ventricular volumetry and Magnetic Resonance Hydrocephalic Index were the most accurate measures (98.5%) in differentiating patients with idiopathic normal pressure hydrocephalus from PSP patients, whereas callosal angle misclassified several PSP patients and showed low positive predictive value (70.0%) in differentiating between these two diseases. All measurements accurately differentiated idiopathic normal pressure hydrocephalus patients from controls. Accuracy values obtained in the training set (automated ventricular volumetry, 98.4%; Magnetic Resonance Hydrocephalic Index, 98.4%; callosal angle, 87.5%) were confirmed in the testing set. CONCLUSIONS: Our study demonstrates that AVV and Magnetic Resonance Hydrocephalic Index were the most accurate measures for differentiation between idiopathic normal pressure hydrocephalus and PSP patients. Magnetic Resonance Hydrocephalic Index is easy to measure and can be used in clinical practice to prevent misdiagnosis and ineffective shunt procedures in idiopathic normal pressure hydrocephalus mimics. © 2020 International Parkinson and Movement Disorder Society.
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Hidrocefalia de Pressão Normal , Paralisia Supranuclear Progressiva , Biomarcadores , Humanos , Hidrocefalia de Pressão Normal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes , Paralisia Supranuclear Progressiva/diagnóstico por imagemRESUMO
INTRODUCTION: There is growing evidence that a proportion of patients with Essential Tremor (ET) may develop a memory impairment over time. However, no studies have evaluated whether hippocampal damage really occur in ET. This study investigated the macro and micro-structural integrity of the hippocampus in ET subjects using a multimodal MRI approach. METHODS: Neuropsychological and MRI data were acquired from 110 participants (60 patients with ET and 50 age-, sex-, and education-matched healthy controls [HC]). Whole-brain T1-weighted and Diffusion Tensor Imaging (DTI) were performed to assess macro-and microstructural alterations. MRI parameters (volume; mean diffusivity [MD]; fractional anisotropy [FA]) of bilateral hippocampi were obtained. In order to evaluate the relationship between MRI alterations and neurocognitive impairment, hippocampal parameters were also correlated with cognitive test scores. RESULTS: Compared to controls, ET patients showed a subclinical memory impairment with significantly lower memory scores, but within the normal ranges. Despite the subclinical damage, however, ET patients showed a significant increase in MD values in the bilateral hippocampi in comparison with HC. A significant correlation was also found between MD and memory scores in ET. CONCLUSION: This study improves the knowledge on memory impairment in ET, as our results demonstrate for the first time the hippocampal microstructural damage related to subclinical memory impairment in ET patients. Further studies are needed before these findings can be considered predictive of a distinct ET subtype or suggestive of a co-occurent dementia.
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Tremor Essencial/patologia , Hipocampo/patologia , Transtornos da Memória/fisiopatologia , Idoso , Imagem de Tensor de Difusão , Tremor Essencial/complicações , Tremor Essencial/diagnóstico , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-IdadeRESUMO
INTRODUCTION: We investigated the disease progression rate in patients with progressive supranuclear palsy-Richardson syndrome (PSP-RS) and PSP-parkinsonism (PSP-P) in comparison with Parkinson disease (PD) patients, using MRPI (Magnetic Resonance Parkinsonism Index), and MRPI 2.0. METHODS: Fifteen PSP-RS patients (disease duration, y, mean ± SD: 2.5 ± 1.1), 16 PSP-P patients (disease duration, y, mean ± SD: 6.5 ± 3.2) and 19 PD patients (disease duration, y, mean ± SD: 3.2 ± 2.3) were enrolled. All patients underwent clinical assessment and MRI at baseline, 1-year, and 2-year follow-up. MRPI, MRPI 2.0 and clinical scores over 1 and 2-years were used to evaluate disease progression rate, and to calculate sample sizes required to power placebo-controlled trials. RESULTS: All groups showed increased clinical motor scores over time whereas only PSP groups had increased MRPI and MRPI 2.0 values over T1 and T2 intervals. The percentage increase over 1 and 2-years of MRPI and MRPI 2.0 values was significantly higher in PSP groups than in PD group, and in PSP-RS than in PSP-P patients while no difference between patient groups was observed when clinical motor scores were considered. Sample size estimates showed that MRPI 2.0 performed better than MRPI and clinical scales. Treatment trials with MRPI 2.0 could be performed over 2-years both in PSP-RS and PSP-P with a sample size per treatment arm of 89 and 170 patients, respectively. CONCLUSIONS: Our results demonstrate that MRPI 2.0 was more powerful than MRPI and clinical motor scales in evaluating PSP progression, and in providing the best sample size estimates for clinical trials.
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Progressão da Doença , Imageamento por Ressonância Magnética , Transtornos Parkinsonianos/diagnóstico , Índice de Gravidade de Doença , Paralisia Supranuclear Progressiva/diagnóstico , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/fisiopatologia , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/fisiopatologiaRESUMO
INTRODUCTION: Apomorphine is a dopamine agonist used in Parkinson's disease (PD), which matches levodopa in terms of the magnitude of effect on the cardinal motor features, such as tremor and bradykinesia. The beneficial effect of this treatment on PD patients with tremor-dominant has widely been demonstrated, although the underlying neural correlates are unknown. We sought to examine the effects of apomorphine on topological characteristics of resting-state functional connectivity networks in tremor-dominant PD (tdPD) patients. METHODS: Sixteen tdPD patients were examined using a combined electromyography-functional magnetic resonance imaging approach. Patients were scanned twice following either placebo (subcutaneous injection of 1â¯mL saline solution) or 1â¯mg of apomorphine injection. Graph analysis methods were employed to investigate the modular organization of functional connectivity networks before and after drug treatment. RESULTS: After injection of apomorphine, evident reduction of tremor symptoms was mirrored by a significant increase in overall connectivity strength and reorganization of the modular structure of the basal ganglia and of the fronto-striatal module. Moreover, we found an increase in the centrality of motor and premotor regions. No differences were found between pre- and post-placebo sessions. CONCLUSION: These results provide new evidence about the effects of apomorphine at a large-scale neural network level showing that drug treatment modifies the brain functional organization of tdPD, increasing the overall resting-state functional connectivity strength, the segregation of striato-frontal regions and the integrative role of motor areas.
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Apomorfina/farmacologia , Agonistas de Dopamina/farmacologia , Lobo Frontal/efeitos dos fármacos , Neostriado/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Tremor/tratamento farmacológico , Idoso , Apomorfina/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Eletromiografia , Feminino , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiopatologia , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neostriado/diagnóstico por imagem , Neostriado/fisiopatologia , Vias Neurais/diagnóstico por imagem , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/fisiopatologia , Método Simples-Cego , Tremor/diagnóstico por imagem , Tremor/fisiopatologiaRESUMO
INTRODUCTION: Track density imaging (TDI) has been proven to be a useful approach able to investigate white matter (WM) anatomical integrity in several neurodegenerative conditions, such as Parkinson's disease (PD) and classical phenotype of Progressive Supranuclear Palsy (PSP) also known as Richardson's syndrome (RS). To the best of our knowledge, no studies have assessed WM changes in PSP-predominant parkinsonism (PSP-P) patients by using a TDI approach, and no studies have explored the potential role of these changes in discriminating patients with PSP-P from those with PSP-RS and PD. METHODS: We used TDI to characterize WM changes in 31â¯PSP-P compared to 36â¯PSP-RS, 36 PD and 37 healthy controls (HC). Then, a support vector machine (SVM) approach was used to evaluate the performance of TDI in discriminating between patient groups. RESULTS: Relative to HC and PD patients, decreased track density in PSP-P patients was found in several WM regions such as the midbrain, superior cerebellar peduncles, cerebellum and corticospinal tract. By contrast, higher values of track density were observed in PSP-P patients compared to PSP-RS. SVM approach using TDI differentiated patients with PSP-P from PD and PSP-RS with an area under the curve of 0.90 and 0.76, respectively. CONCLUSIONS: Our findings suggest that TDI may represent a useful approach for characterizing WM changes in PSP-P patients representing a potential new MRI biomarker in distinguishing this PSP phenotype from PD.
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Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Neuroimagem/métodos , Doença de Parkinson/diagnóstico por imagem , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Idoso , Encéfalo/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Máquina de Vetores de Suporte , Paralisia Supranuclear Progressiva/patologia , Substância Branca/patologiaRESUMO
BACKGROUND: Fragile X-associated tremor/ataxia syndrome is a late-onset neurodegenerative disorder that affects about 40% of carriers of CGG-repeat expansions in the premutation range within the fragile X gene (FMR1). Main clinical features include intention tremor, cerebellar ataxia, and parkinsonism. Recently, great emphasis on the deposition of soluble aggregates produced by a RAN translation process, as main pathogenic mechanism, has been given. These aggregates contain a small protein with a polyglycine stretch on the aminoterminal end named FMRpolyG and, so far, have been isolated and characterized in drosophila and mouse models, in post mortem brain of fragile X-associated tremor/ataxia syndrome patients, in fibroblasts of fragile primary ovarian insufficiency patients, but never in fibroblasts from a fragile X-associated tremor/ataxia living patients. In adult carriers the syndrome is frequently misdiagnosed due to the lack of specific markers. METHODS: We standardized immunocytochemistry, immunoprecipitation and western blot procedures to study and biochemically characterize the FMRpolyG protein in fibroblasts from human skin biopsy. RESULTS: We demonstrate for the first time, in fibroblasts from a patient affected by Fragile X-associated tremor/ataxia syndrome, the presence ex vivo of inclusions consisting of FMRpolyG- Hsp70 soluble aggregates. CONCLUSION: These observations can pave the way to develop a cellular model for studying ex vivo and in vitro the mechanisms involved in the production of FMRpolyG aggregates, their toxicity, and the role of the FMRpolyG-Hsp70 interaction in the pathogenesis of fragile X-associated tremor/ataxia syndrome.