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1.
Neurol Sci ; 45(3): 1233-1242, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37831214

RESUMO

BACKGROUND: Rituximab, a B-cell depleting monoclonal antibody, represents an option for the treatment of refractory myasthenia gravis (MG). Its use is more established in muscle-specific tyrosine kinase positive (MuSK +) patients, while its role in managing acetylcholine receptor positive (AChR +), or double seronegative (DSN) patients, remains less clear. This study evaluates the long-term effectiveness and safety of rituximab in MG of various serotypes. METHODS: We conducted an open-label study of MG patients receiving rituximab. Adults with generalized refractory MG, either anti-AChR + or DSN, and anti-MuSK + , refractory or not, who had follow-up > 12 months were selected. Change in quantitative myasthenia gravis (QMG) score at last follow-up, compared with baseline was a primary outcome, as well as factors affecting response to treatment. Secondary outcomes included, long-term safety, the steroid-sparing effect and relapse rates post-rituximab. RESULTS: Thirty patients (16 anti-AChR + , 6 anti-MuSK + , 8 DSN) followed for a mean of 33.3 months were included. Mean scores pre-rituximab compared to last follow-up significantly decreased (p < 0.001), from 11 ± 4.1 to 4.3 ± 3.8, and from 1.9 to 0.3 regarding QMG and relapse rate per patient/year, respectively, while in 93.1% a daily steroid dose ≤ 10 mg was achieved. Antibody status was the only factor independently influencing several endpoints. Throughout the study period no crises or deaths occurred. CONCLUSION: The present study supports that rituximab is an effective and well tolerated treatment for refractory anti-AChR + and DSN MG patients, while anti-MuSK + remains the group experiencing the greater benefits.


Assuntos
Fatores Imunológicos , Miastenia Gravis , Adulto , Humanos , Rituximab/uso terapêutico , Fatores Imunológicos/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Miastenia Gravis/tratamento farmacológico , Esteroides/uso terapêutico , Recidiva , Autoanticorpos
2.
Dysphagia ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517530

RESUMO

To review the assessment methods of dysphagia as a criterion for the decision-making process for Percutaneous Endoscopic Gastrostomy (PEG) placement in patients with Amyotrophic Lateral Sclerosis (ALS). Systematic review. A search was conducted in three databases (EMBASE, CINAHL, PUBMED) in December 2022 and updated in July 2023. Two reviewers independently screened, selected, and extracted data. Study quality was appraised using the Joanna Briggs Institute Critical Appraisal Tools. Systematic review registration number in the International Prospective Register of Systematic Reviews (PROSPERO): CRD42022385461. The searches identified 240 records. The 10 eligible studies included 2 case reports, 4 retrospective studies, 3 prospective studies, and 1 cohort observational study. Study quality was low, with most studies having moderate to high risk of bias. Dysphagia is a common criterion for decision-making. Dysphagia assessment is usually in the form of either self-reports, objective instrumental assessments, or both. Dysphagia is a common criterion for the decision-making process, yet is missing in clinical guidelines. Establishing the optimal means of dysphagia assessment is important for timely decision-making procedures, so that life-threatening consequences of dysphagia are minimized.

3.
Int J Mol Sci ; 25(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38339074

RESUMO

In this narrative review, we delved into the intricate interplay between Apolipoprotein E (APOE) alleles (typically associated with Alzheimer's disease-AD) and alpha-synucleinopathies (aS-pathies), involving Parkinson's disease (PD), Parkinson's disease dementia (PDD), dementia with Lewy bodies (DLB), and multiple-system atrophy (MSA). First, in-vitro, animal, and human-based data on the exacerbating effect of APOE4 on LB pathology were summarized. We found robust evidence that APOE4 carriage constitutes a risk factor for PDD-APOE2, and APOE3 may not alter the risk of developing PDD. We confirmed that APOE4 copies confer an increased hazard towards DLB, as well. Again APOE2 and APOE3 appear unrelated to the risk of conversion. Of note, in individuals with DLB APOE4, carriage appears to be intermediately prevalent between AD and PDD-PD (AD > DLB > PDD > PD). Less consistency existed when it came to PD; APOE-PD associations tended to be markedly modified by ethnicity. Finally, we failed to establish an association between the APOE gene and MSA. Phenotypic associations (age of disease onset, survival, cognitive-neuropsychiatric- motor-, and sleep-related manifestations) between APOE alleles, and each of the aforementioned conditions were also outlined. Finally, a synopsis of literature gaps was provided followed by suggestions for future research.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Demência , Doença por Corpos de Lewy , Doença de Parkinson , Sinucleinopatias , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/complicações , Apolipoproteína E2 , Apolipoproteína E3 , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Demência/patologia , Doença por Corpos de Lewy/patologia , Doença de Parkinson/patologia , Sinucleinopatias/complicações
4.
J Peripher Nerv Syst ; 28(1): 41-46, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36453598

RESUMO

Electrodiagnostic (EDx) studies play a key role in the investigation of suspected Guillain-Barré syndrome (GBS), providing diagnostic and prognostic information. However, initial EDx findings may not fulfill the neurophysiological criteria for the disease. The aim of this study was to estimate the occurrence and characteristics of A-waves and repeaters F-waves (Freps), both late motor responses identical in latency and configuration, in early stages of GBS. We retrospectively analyzed the initial nerve conduction study (NCS) of 26 GBS patients performed within 10 days from symptom onset. The final subtype diagnosis was acute inflammatory demyelinating polyneuropathy (AIDP) in 16 patients (six met the criteria at the initial EDx study and 10 at follow-up) and acute motor axonal neuropathy (AMAN) in 10 patients (six initially). Identical late responses were commonly found in the majority of nerves (84%). A-waves were present in 59% and an increased frequency of Freps was calculated in 61% of the 105 studied nerves. A-waves morphology (single or complex) could not distinguish between AIDP and AMAN. Nerves with normal NCS had a significantly higher frequency of A-waves, either isolated or in combination with increased index total Freps, as compared to nerves with low compound muscle action potential (CMAP) amplitudes or conduction block. Our findings suggest that both late responses can be useful as early markers of conduction changes of various pathophysiology, being frequently present even prior to abnormalities of CMAP parameters.


Assuntos
Síndrome de Guillain-Barré , Humanos , Síndrome de Guillain-Barré/diagnóstico , Condução Nervosa/fisiologia , Estudos Retrospectivos , Amantadina
5.
Sensors (Basel) ; 23(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37765907

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor and nonmotor impairment with various implications on patients' quality of life. Since currently available therapies are only symptomatic, identifying individuals with prodromal, preclinical, or early-stage PD is crucial, as they would be ideal candidates for future disease-modifying therapies. Our analysis aims to develop a robust model for accurate PD detection using accelerometer data collected from PD and non-PD individuals with mild or no tremor during phone conversations. An open-access dataset comprising accelerometer recordings from 22 PD patients and 11 healthy controls (HCs) was utilized. The data were preprocessed to extract relevant time-, frequency-, and energy-related features, and a bidirectional long short-term memory (Bi-LSTM) model with attention mechanism was employed for classification. The performance of the model was evaluated using fivefold cross-validation, and metrics of accuracy, precision, recall, specificity, and f1-score were computed. The proposed model demonstrated high accuracy (98%), precision (99%), recall (98%), specificity (96%), and f1-score (98%) in accurately distinguishing PD patients from HCs. Our findings indicate that the proposed model outperforms existing approaches and holds promise for detection of PD with subtle symptoms, like tremor, in the wild. Such symptoms can present in the early or even prodromal stage of the disease, and appropriate mobile-based applications may be a practical tool in real-life settings to alert individuals at risk to seek medical assistance or give patients feedback in monitoring their symptoms.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Qualidade de Vida , Tremor , Benchmarking , Comunicação
6.
Sensors (Basel) ; 23(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37112243

RESUMO

Parkinson's disease (PD) is characterized by a variety of motor and non-motor symptoms, some of them pertaining to gait and balance. The use of sensors for the monitoring of patients' mobility and the extraction of gait parameters, has emerged as an objective method for assessing the efficacy of their treatment and the progression of the disease. To that end, two popular solutions are pressure insoles and body-worn IMU-based devices, which have been used for precise, continuous, remote, and passive gait assessment. In this work, insole and IMU-based solutions were evaluated for assessing gait impairment, and were subsequently compared, producing evidence to support the use of instrumentation in everyday clinical practice. The evaluation was conducted using two datasets, generated during a clinical study, in which patients with PD wore, simultaneously, a pair of instrumented insoles and a set of wearable IMU-based devices. The data from the study were used to extract and compare gait features, independently, from the two aforementioned systems. Subsequently, subsets comprised of the extracted features, were used by machine learning algorithms for gait impairment assessment. The results indicated that insole gait kinematic features were highly correlated with those extracted from IMU-based devices. Moreover, both had the capacity to train accurate machine learning models for the detection of PD gait impairment.


Assuntos
Doença de Parkinson , Dispositivos Eletrônicos Vestíveis , Humanos , Doença de Parkinson/diagnóstico , Marcha , Sapatos , Modalidades de Fisioterapia
7.
Muscle Nerve ; 65(5): 607-611, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35195920

RESUMO

INTRODUCTION/AIMS: A subgroup of myasthenia gravis (MG) patients fail to respond adequately to recommended treatments, a condition referred to as refractory MG. During the refractory phase, patients experience persistent debilitating symptoms with potential life-threatening events or inability to reduce immunosuppressant dosages and minimize long-term toxicities. METHODS: We conducted a retrospective, single-center study of 113 MG patients to investigate the autoantibody profile and clinical characteristics of refractory MG patients, compared with nonrefractory patients, based on predefined criteria. RESULTS: Fifteen patients (13.3%) were classified as refractory. Double-seronegative MG (DSNMG), without detectable nicotinic acetylcholine receptor (AChR) or muscle-specific tyrosine kinase (MuSK) antibodies, was identified in six refractory patients, significantly higher than those with nonrefractory MG (40% vs 16.3%; P = .031). None of the refractory patients had MuSK antibodies. Patients in the refractory group more frequently had an earlier disease onset, thymic pathology, and thymectomy (P ≤. 03 for all). DISCUSSION: In this study, patients with refractory MG were more likely than those with nonrefractory MG to be DSN; and refractory DSNMG patients had worse MGFA classes in their recent visit compared with anti-AChR positive refractory patients. Refractory DSNMG patients may represent a distinct group that requires more individualized and targeted treatment approaches.


Assuntos
Miastenia Gravis , Receptores Nicotínicos , Autoanticorpos , Humanos , Miastenia Gravis/diagnóstico , Estudos Retrospectivos , Timectomia
8.
Clin Exp Rheumatol ; 40(4): 838-840, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35485423

RESUMO

We present herein the case of a patient with brachial plexopathy, the first manifestation of giant cell arteritis (GCA). A 71-year-old woman presented with a subacute-onset weakness of her upper extremities; the patient had an initially good clinical response to steroid treatment. However, a few weeks after steroid discontinuation, she manifested fever and fatigue and increased serum markers consistent with a systemic inflammatory response. A PET-CT scan revealed an increased uptake in the subclavian arteries and a temporal biopsy was typical for GCA. Oral administration of high dosage steroids improved the patient's clinical symptoms and normalised her inflammatory serum markers.


Assuntos
Arterite de Células Gigantes , Idoso , Biomarcadores , Biópsia , Feminino , Arterite de Células Gigantes/diagnóstico , Arterite de Células Gigantes/diagnóstico por imagem , Humanos , Masculino , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Síndrome , Artérias Temporais/diagnóstico por imagem , Artérias Temporais/patologia
9.
Sensors (Basel) ; 22(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36560313

RESUMO

Parkinson's disease (PD) is one of the most prevalent neurological diseases, described by complex clinical phenotypes. The manifestations of PD include both motor and non-motor symptoms. We constituted an experimental protocol for the assessment of PD motor signs of lower extremities. Using a pair of sensor insoles, data were recorded from PD patients, Elderly and Adult groups. Assessment of PD patients has been performed by neurologists specialized in movement disorders using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS)-Part III: Motor Examination, on both ON and OFF medication states. Using as a reference point the quantified metrics of MDS-UPDRS-Part III, severity levels were explored by classifying normal, mild, moderate, and severe levels of PD. Elaborating the recorded gait data, 18 temporal and spatial characteristics have been extracted. Subsequently, feature selection techniques were applied to reveal the dominant features to be used for four classification tasks. Specifically, for identifying relations between the spatial and temporal gait features on: PD and non-PD groups; PD, Elderly and Adults groups; PD and ON/OFF medication states; MDS-UPDRS: Part III and PD severity levels. AdaBoost, Extra Trees, and Random Forest classifiers, were trained and tested. Results showed a recognition accuracy of 88%, 73% and 81% for, the PD and non-PD groups, PD-related medication states, and PD severity levels relevant to MDS-UPDRS: Part III ratings, respectively.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/tratamento farmacológico , Marcha , Testes de Estado Mental e Demência , Aprendizado de Máquina , Índice de Gravidade de Doença
10.
Neurol Sci ; 42(6): 2167-2172, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33745041

RESUMO

BACKGROUND: Acute subarachnoid hemorrhage (SAH) due to aneurysmal rupture is a devastating vascular disease accounting for 5% of strokes. COVID-19 pandemic resulted in a decrease in elective and emergency admissions in the majority of neurosurgical centers. The main hypothesis was that fear of COVID-19 may have prevented patients with critical medical or surgical emergencies from actively presenting in emergency departments and outpatient clinics. METHODS: We conducted a single-center, retrospective, observational study searching our institutional data regarding the incidence of spontaneous subarachnoid hemorrhage (SAH) and compare the admissions in two different periods: the pre COVID-19 with the COVID-19 period. RESULTS: The study cohort was comprised of a total of 99 patients. The mean (SD) weekly case rate of patients with SAH was 1.1 (1.1) during the pre-COVID-19 period, compared to 1.7 (1.4) during the COVID-19 period. Analysis revealed that the volume of admitted patients with SAH was 1.5-fold higher during the COVID period compared to the pre-COVID period and this was statistically significant (ExpB = 1.5, CI 95% 1-2.3, p = 0.044). Difference in mortality did not reach any statistical significance between the two periods (p = 0.097), as well as patients' length of stay (p = 0.193). CONCLUSIONS: The presented data cover a more extended time period than so far published reports; it is reasonable that our recent experience may well be demonstrating a general realistic trend of overall increase in aneurysmal rupture rates during lockdown. Hospitalization of patients with SAH cannot afford any reductions in facilities, equipment, or personnel if optimum outcomes are desirable.


Assuntos
COVID-19 , Hemorragia Subaracnóidea , Controle de Doenças Transmissíveis , Grécia/epidemiologia , Hospitalização , Humanos , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/terapia
11.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923809

RESUMO

Gait analysis is crucial for the detection and management of various neurological and musculoskeletal disorders. The identification of gait events is valuable for enhancing gait analysis, developing accurate monitoring systems, and evaluating treatments for pathological gait. The aim of this work is to introduce the Smart-Insole Dataset to be used for the development and evaluation of computational methods focusing on gait analysis. Towards this objective, temporal and spatial characteristics of gait have been estimated as the first insight of pathology. The Smart-Insole dataset includes data derived from pressure sensor insoles, while 29 participants (healthy adults, elderly, Parkinson's disease patients) performed two different sets of tests: The Walk Straight and Turn test, and a modified version of the Timed Up and Go test. A neurologist specialized in movement disorders evaluated the performance of the participants by rating four items of the MDS-Unified Parkinson's Disease Rating Scale. The annotation of the dataset was performed by a team of experienced computer scientists, manually and using a gait event detection algorithm. The results evidence the discrimination between the different groups, and the verification of established assumptions regarding gait characteristics of the elderly and patients suffering from Parkinson's disease.


Assuntos
Doença de Parkinson , Dispositivos Eletrônicos Vestíveis , Adulto , Idoso , Marcha , Análise da Marcha , Humanos , Doença de Parkinson/diagnóstico , Equilíbrio Postural , Estudos de Tempo e Movimento
12.
J Neurol Neurosurg Psychiatry ; 90(10): 1078-1090, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31129620

RESUMO

BACKGROUND: Deep brain stimulation (DBS) can be an effective therapy for tics and comorbidities in select cases of severe, treatment-refractory Tourette syndrome (TS). Clinical responses remain variable across patients, which may be attributed to differences in the location of the neuroanatomical regions being stimulated. We evaluated active contact locations and regions of stimulation across a large cohort of patients with TS in an effort to guide future targeting. METHODS: We collected retrospective clinical data and imaging from 13 international sites on 123 patients. We assessed the effects of DBS over time in 110 patients who were implanted in the centromedial (CM) thalamus (n=51), globus pallidus internus (GPi) (n=47), nucleus accumbens/anterior limb of the internal capsule (n=4) or a combination of targets (n=8). Contact locations (n=70 patients) and volumes of tissue activated (n=63 patients) were coregistered to create probabilistic stimulation atlases. RESULTS: Tics and obsessive-compulsive behaviour (OCB) significantly improved over time (p<0.01), and there were no significant differences across brain targets (p>0.05). The median time was 13 months to reach a 40% improvement in tics, and there were no significant differences across targets (p=0.84), presence of OCB (p=0.09) or age at implantation (p=0.08). Active contacts were generally clustered near the target nuclei, with some variability that may reflect differences in targeting protocols, lead models and contact configurations. There were regions within and surrounding GPi and CM thalamus that improved tics for some patients but were ineffective for others. Regions within, superior or medial to GPi were associated with a greater improvement in OCB than regions inferior to GPi. CONCLUSION: The results collectively indicate that DBS may improve tics and OCB, the effects may develop over several months, and stimulation locations relative to structural anatomy alone may not predict response. This study was the first to visualise and evaluate the regions of stimulation across a large cohort of patients with TS to generate new hypotheses about potential targets for improving tics and comorbidities.


Assuntos
Estimulação Encefálica Profunda/métodos , Globo Pálido/diagnóstico por imagem , Cápsula Interna/diagnóstico por imagem , Núcleo Accumbens/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Síndrome de Tourette/terapia , Adolescente , Adulto , Atlas como Assunto , Estudos de Coortes , Comportamento Compulsivo/psicologia , Feminino , Humanos , Núcleos Intralaminares do Tálamo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Comportamento Obsessivo/psicologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Síndrome de Tourette/diagnóstico por imagem , Síndrome de Tourette/psicologia , Resultado do Tratamento , Adulto Jovem
13.
Stereotact Funct Neurosurg ; 95(4): 251-258, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28787721

RESUMO

BACKGROUND: Deep brain stimulation (DBS) in patients with severe, refractory Tourette syndrome (TS) has demonstrated promising but variable results thus far. The thalamus and anteromedial globus pallidus internus (amGPi) have been the most commonly stimulated sites within the cortico-striato thalamic circuit, but an optimal target is yet to be elucidated. OBJECTIVES: This study of 15 patients with long-term amGPi DBS for severe TS investigated whether a specific anatomical site within the amGPi correlated with optimal clinical outcome for the measures of tics, obsessive compulsive behaviour (OCB), and mood. METHODS: Validated clinical assessments were used to measure tics, OCB, quality of life, anxiety, and depression before DBS and at the latest follow-up (17-82 months). Electric field simulations were created for each patient using information on electrode location and individual stimulation parameters. A subsequent regression analysis correlated these patient-specific simulations to percentage changes in outcome measures in order to identify any significant voxels related to clinical improvement. RESULTS: A region within the ventral limbic GPi, specifically on the medial medullary lamina in the pallidum at the level of the AC-PC, was significantly associated with improved tics but not mood or OCB outcome. CONCLUSIONS: This study adds further support to the application of DBS in a tic-related network, though factors such as patient sample size and clinical heterogeneity remain as limitations and replication is required.


Assuntos
Estimulação Encefálica Profunda/métodos , Globo Pálido/diagnóstico por imagem , Síndrome de Tourette/diagnóstico por imagem , Síndrome de Tourette/terapia , Adolescente , Adulto , Estimulação Encefálica Profunda/normas , Feminino , Seguimentos , Globo Pálido/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
14.
Mov Disord ; 31(7): 1020-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27104232

RESUMO

BACKGROUND: Measuring microstructure alterations with diffusion tensor imaging in PD is potentially a valuable tool to use as a biomarker for early diagnosis and to track disease progression. Previous studies have reported a specific decrease of nigral fractional anisotropy in PD. However, to date the effect of disease progression on nigral or striatal diffusion indices has not been fully explored. METHODS: We have conducted a cross-sectional and longitudinal diffusion tensor imaging study in 18 early stage, treated PD patients and 14 age-matched controls. PD patients were scanned on 2 occasions OFF medication, 19.3 months apart (standard deviation = 3.1 months). Longitudinal change of regional nigral and striatal measures of fractional anisotropy and mean diffusivity were calculated using a region-of-interest approach. RESULTS: Region-of-interest analysis demonstrated that at baseline, PD patients and controls did not differ in regard to diffusion indices in any region assessed. A significant difference of nigral fractional anisotropy and mean diffusivity between controls and PD patients at follow-up was detected and confirmed with longitudinal analysis within PD patients. Alterations in striatal regions were not detected in either group or over time. CONCLUSION: Our findings indicate that nigral diffusion measure may be a valuable measure of disease progression. In the future, larger longitudinal studies will confirm whether diffusion indices may serve as sensitive and clinically meaningful measures of disease progression in PD. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Imagem de Tensor de Difusão/métodos , Progressão da Doença , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
15.
Exp Brain Res ; 234(7): 1837-1848, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26892884

RESUMO

The subthalamic nucleus (STN) is proposed to modulate response thresholds and speed-accuracy trade-offs. In situations of conflict, the STN is considered to raise response thresholds, allowing time for the accumulation of information to occur before a response is selected. Conversely, speed pressure is thought to reduce the activity of the STN and lower response thresholds, resulting in fast, errorful responses. In Parkinson's disease (PD), subthalamic nucleus deep brain stimulation (STN-DBS) reduces the activity of the nucleus and improves motor symptoms. We predicted that the combined effects of STN stimulation and speed pressure would lower STN activity and lead to fast, errorful responses, hence resulting in impulsive action. We used the motion discrimination 'moving-dots' task to assess speed-accuracy trade-offs, under both speed and accuracy instructions. We assessed 12 patients with PD and bilateral STN-DBS and 12 age-matched healthy controls. Participants completed the task twice, and the patients completed it once with STN-DBS on and once with STN-DBS off, with order counterbalanced. We found that STN stimulation was associated with significantly faster reaction times but more errors under speed instructions. Application of the drift diffusion model showed that stimulation resulted in lower response thresholds when acting under speed pressure. These findings support the involvement of the STN in the modulation of speed-accuracy trade-offs and establish for the first time that speed pressure alone, even in the absence of conflict, can result in STN stimulation inducing impulsive action in PD.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Comportamento Impulsivo/fisiologia , Doença de Parkinson/terapia , Desempenho Psicomotor/fisiologia , Núcleo Subtalâmico/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Subtalâmico/fisiopatologia
16.
Am J Dermatopathol ; 37(2): 138-44, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25614949

RESUMO

Cancer stem cells and the misregulation of epigenetic modifications have been identified to possess a determinative role in carcinogenesis. The purpose of this study was to investigate the expression profile of EZH2 and H3K4me2 and H3K27me3, which constitute stem cell-like "bivalent" domains, in cutaneous malignant melanoma. A comparative analysis of their immunohistochemical expression between the invasion front (IF) and the inner tumor mass was also evaluated. Immunohistochemical methodology was performed on sections of 89 melanoma lesions from 79 patients. The 3 markers studied were identified in the cell nuclei of melanoma cells, nevus cells, and normal epidermal keratinocytes. A specific distribution pattern of H3K4me2 and H3K27me3 was found, as stronger levels were localized at the IF of the tumor (P = 0.034 and P < 0.01, respectively). In general, H3K4me2 and H3K27me3 levels were lower in metastatic with respect to primary melanoma cases (P = 0.0065 and P = 0.027, respectively). Advanced melanoma demonstrated significantly lower H3K4 immunohistochemical expression than did cases of lowest Clark level (I) (P = 0.038) or low Breslow depth (≤1 mm; P < 0.001). Furthermore, EZH2 expression in melanoma cells was higher compared with that in nevus cells (P = 0.02). A positive correlation between EZH2-H3K27me3 (P = 0.03) and H3K4me2-H3K27me3 (P < 0.01) in melanoma cells was also found. Our results suggest the possibility that combined immunohistochemical expression of EZH2, H3K4me2, and H3K27me3 might identify cancer cells with potential stem cell properties, particularly at the IF of this malignancy. This hypothesis should be further investigated, as many of the epigenetic changes are reversible via pharmacologic manipulations and new therapies, overpassing the resistance of advanced melanoma, may be developed.


Assuntos
Biomarcadores Tumorais/análise , Epigênese Genética , Histonas/análise , Imuno-Histoquímica , Melanoma/química , Melanoma/genética , Complexo Repressor Polycomb 2/análise , Neoplasias Cutâneas/química , Neoplasias Cutâneas/genética , Adulto , Idoso , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Humanos , Masculino , Melanoma/secundário , Metilação , Pessoa de Meia-Idade , Invasividade Neoplásica , Células-Tronco Neoplásicas/química , Células-Tronco Neoplásicas/patologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/patologia
17.
Neuromodulation ; 18(2): 90-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25284508

RESUMO

OBJECTIVES: The aim of this study was to investigate the deep brain stimulation (DBS) electric field distribution in proton-density MRI scans visualizing the globus pallidus internus (GPi) of patients with Gilles de la Tourette syndrome (GTS), along with its relation to the anatomy. METHODS: Patient-specific brain tissue models (n = 7) with bilateral DBS electrodes in the GPi were set up using the finite element method in five patients who had undergone stereotactic proton-density MRI-guided surgery and showed variable improvement with DBS. Simulations (n = 27) of the electric field were performed and the results visualized on the respective preoperative stereotactic MRI scans. The mean electric field volumes (n = 81) within the 0.1, 0.15, and 0.2 V/mm isosurfaces were calculated and compared with the anatomy. RESULTS: Visualization of the simulated electric field confirmed that the anteromedial limbic GPi was the main stimulated target for four of the patients and the posteromedial sensorimotor GPi for one. Larger volumes extended asymmetrically, with parts of fields stretching into the lamina between GPi and globus pallidus externus and into the internal capsule. There was a high correlation (r = 0.994, n = 54) between volumes and brain sides, but with a systematic shift toward the right side, especially for the larger volumes. Simulations with homogeneous tissue models showed no differences. CONCLUSIONS: Patient-specific DBS electric field simulations in the GPi as visualized on proton-density MR scans can be implemented in patients with GTS. Visualization of electric fields together with stereotactic thin-slice MRI can provide further support when predicting anatomical structures possibly influenced by DBS in this complex disorder.


Assuntos
Estimulação Encefálica Profunda/métodos , Globo Pálido/fisiologia , Síndrome de Tourette/terapia , Adulto , Simulação por Computador , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Resultado do Tratamento , Adulto Jovem
18.
J Neurol Neurosurg Psychiatry ; 85(12): 1419-25, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24790212

RESUMO

BACKGROUND: Subthalamic nucleus (STN) deep brain stimulation (DBS) represents a well-established treatment for patients with advanced Parkinson's disease (PD) insufficiently controlled with medical therapies. This study presents the long-term outcomes of patients with PD treated with STN-DBS using an MRI-guided/MRI-verified approach without microelectrode recording. METHODS: A cohort of 41 patients who underwent STN-DBS were followed for a minimum period of 5 years, with a subgroup of 12 patients being followed for 8-11 years. Motor status was evaluated using part III of the Unified Parkinson's Disease Rating Scale (UPDRS-III), in on- and off-medication/on-stimulation conditions. Preoperative and postoperative assessments further included activities of daily living (UPDRS-II), motor complications (UPDRS-IV), neuropsychological and speech assessments, as well as evaluation of quality of life. Active contacts localisation was calculated and compared with clinical outcomes. RESULTS: STN-DBS significantly improved the off-medication UPDRS-III scores, compared with baseline. However, UPDRS scores increased over time after DBS. Dyskinesias, motor fluctuations and demands in dopaminergic medication remained significantly reduced in the long term. Conversely, UPDRS-III on-medication scores deteriorated at 5 and 8 years, mostly driven by axial and bradykinesia subscores. Quality of life, as well as depression and anxiety scores, did not significantly change at long-term follow-up compared with baseline. In our series, severe cognitive decline was observed in 17.1% and 16.7% of the patients at 5 and 8 years respectively. CONCLUSIONS: Our data confirm that STN-DBS, using an MRI-guided/MRI-verified technique, remains an effective treatment for motor 'off' symptoms of PD in the long term with low morbidity.


Assuntos
Estimulação Encefálica Profunda/métodos , Imagem por Ressonância Magnética Intervencionista/métodos , Doença de Parkinson/terapia , Atividades Cotidianas , Feminino , Humanos , Bateria Neuropsicológica de Luria-Nebraska , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Tálamo , Resultado do Tratamento
19.
J Neurol ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090229

RESUMO

OBJECTIVE: Published evidence suggests that cognitive impairment during a TGA (transient global amnesia) spell may not be confined to episodic memory. We undertook a systematic review to determine the pattern of cognitive deficits during a TGA episode. As a secondary objective, we aimed to delineate the course of cognitive recovery. METHODS: MEDLINE, EMBASE, CENTRAL, and Google scholar were systematically searched up to October 2023. Observational controlled studies including 10 or more TGA patients (Hodges and Warlow criteria) were retrieved. Data from case-control, cross-sectional, and cohort studies were reviewed and qualitatively synthesized. RESULTS: Literature search yielded 1302 articles. After the screening of titles and abstracts, 115 full texts were retrieved and 17 of them were included in the present systematic review. During the acute phase, spatiotemporal disorientation, dense anterograde and variable retrograde amnesia, semantic memory retrieval difficulties, and working memory deficits comprised the neuropsychological profile of patients with TGA. Visuospatial abilities, attention and psychomotor speed, semantic memory, confrontation naming, and other measures of executive function (apart from semantic fluency and working memory) were consistently found normal. In the course of recovery, after the resolution of repetitive questioning, the restoration of spatiotemporal orientation follows, working memory and semantic memory retrieval ensue, while episodic memory impairment persists for longer. Meticulous evaluations may reveal subtle residual memory (especially recognition) deficits even after 24 h. CONCLUSIONS: Μemory impairment, spatiotemporal disorientation, and working memory deficits constitute the pattern of cognitive impairment during a TGA spell. Residual memory deficits may persist even after 24 h.

20.
Mov Disord ; 28(10): 1370-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23818421

RESUMO

Variation in the genetic risk(s) of developing Parkinson's disease (PD) undoubtedly contributes to the subsequent phenotypic heterogeneity. Although patients with PD who undergo deep brain stimulation (DBS) are a skewed population, they represent a valuable resource for exploring the relationships between heterogeneous phenotypes and PD genetics. In this series, 94 patients who underwent DBS were screened for mutations in the most common genes associated with PD. The consequent genetic subgroups of patients were compared with respect to phenotype, levodopa (l-dopa), and DBS responsiveness. An unprecedented number (29%) of patients tested positive for at least 1 of the currently known PD genes. Patients with Parkin mutations presented at the youngest age but had many years of disease before needing DBS, whereas glucocerebrosidase (GBA) mutation carriers reached the threshold of needing DBS earlier, and developed earlier cognitive impairment after DBS. DBS cohorts include large numbers of gene positive PD patients and can be clinically instructive in the exploration of genotype-phenotype relationships.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson/genética , Doença de Parkinson/fisiopatologia , Adulto , Idade de Início , Antiparkinsonianos/uso terapêutico , Criança , Dopaminérgicos/uso terapêutico , Éxons/genética , Feminino , Amplificação de Genes , Genótipo , Glucosilceramidase/genética , Heterozigoto , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mutação/genética , Doença de Parkinson/terapia , Fenótipo , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/genética , Ubiquitina-Proteína Ligases/genética , Adulto Jovem
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