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1.
J Neurol ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38767661

RESUMO

BACKGROUND & PURPOSE: In this retrospective study, we aimed at defining the clinical, paraclinical and outcome features of acute neurological syndromes associated with anti-GQ1b antibodies. RESULTS: We identified 166 patients with neurological symptoms appearing in less than 1 month and anti-GQ1b antibodies in serum between 2012 and 2022. Half were female (51%), mean age was 50 years (4-90), and the most frequent clinical features were areflexia (80% of patients), distal upper and lower limbs sensory symptoms (78%), ophthalmoplegia (68%), sensory ataxia (67%), limb muscle weakness (45%) and bulbar weakness (45%). Fifty-three patients (32%) presented with complete (21%) and incomplete (11%) Miller Fisher syndrome (MFS), thirty-six (22%) with Guillain-Barre syndrome (GBS), one (0.6%) with Bickerstaff encephalitis (BE), and seventy-three (44%) with mixed MFS, GBS & BE clinical features. Nerve conduction studies were normal in 46% of cases, showed demyelination in 28%, and axonal loss in 23%. Anti-GT1a antibodies were found in 56% of cases, increased cerebrospinal fluid protein content in 24%, and Campylobacter jejuni infection in 7%. Most patients (83%) were treated with intravenous immunoglobulins, and neurological recovery was complete in 69% of cases at 1 year follow-up. One patient died, and 15% of patients relapsed. Age > 70 years, initial Intensive Care Unit (ICU) admission, and absent anti-GQ1b IgG antibodies were predictors of incomplete recovery at 12 months. No predictors of relapse were identified. CONCLUSION: This study from Western Europe shows acute anti-GQ1b antibody syndrome presents with a large clinical phenotype, a good outcome in 2/3 of cases, and frequent relapses.

2.
Sci Rep ; 14(1): 4643, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409319

RESUMO

To date, little is known about the usefulness of ultra-high frequency ultrasound (UHF-US, 50-70 MHz) in clinical practice for the diagnosis of dysimmune neuropathies. We present a prospective study aimed at comparing UHF-US alterations of nerves and fascicles in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), distal CIDP (d-CIDP) and anti-MAG neuropathy and their relationships with clinical and electrodiagnostic (EDX) features. 28 patients were included (twelve CIDP, 6 d-CIDP and 10 anti-MAG) and ten healthy controls. Each patient underwent neurological examination, EDX and UHF-US study of median and ulnar nerves bilaterally. UHF-US was reliable in differentiating immune neuropathies from controls when using mean and/or segmental nerve and/or fascicle cross-sectional area (CSA); furthermore, fascicle ratio (fascicle/nerve CSA) was a reliable factor for differentiating d-CIDP from other types of polyneuropathies. The fascicle CSA appears to be more increased in CIDP and its variant than in anti-MAG neuropathy. UHF-US offers information beyond simple nerve CSA and allows for a better characterization of the different forms of dysimmune neuropathies.


Assuntos
Polineuropatias , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Humanos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia , Nervo Ulnar/diagnóstico por imagem , Glicoproteína Associada a Mielina , Autoanticorpos , Nervos Periféricos/diagnóstico por imagem , Condução Nervosa
3.
Eur J Neurol ; 29(12): 3547-3555, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35969369

RESUMO

BACKGROUND AND PURPOSE: In this retrospective study involving 14 university hospitals from France and Switzerland, the aim was to define the clinicopathological features of chronic neuropathies with anti-disialosyl ganglioside immunoglobulin M (IgM) antibodies (CNDA). RESULTS: Fifty-five patients with a polyneuropathy evolving for more than 2 months and with at least one anti-disialosyl ganglioside IgM antibody, that is, anti-GD1b, -GT1b, -GQ1b, -GT1a, -GD2 and -GD3, were identified. Seventy-eight percent of patients were male, mean age at disease onset was 55 years (30-76) and disease onset was progressive (82%) or acute (18%). Patients presented with limb sensory symptoms (94% of cases), sensory ataxia (85%), oculomotor weakness (36%), limb motor symptoms (31%) and bulbar muscle weakness (18%). Sixty-five percent of patients had a demyelinating polyradiculoneuropathy electrodiagnostic profile and 24% a sensory neuronopathy profile. Anti-GD1b antibodies were found in 78% of cases, whilst other anti-disialosyl antibodies were each observed in less than 51% of patients. Other features included nerve biopsy demyelination (100% of cases), increased cerebrospinal fluid protein content (75%), IgM paraprotein (50%) and malignant hemopathy (8%). Eighty-six percent of CNDA patients were intravenous immunoglobulins-responsive, and rituximab was successfully used as second-line treatment in 50% of cases. Fifteen percent of patients had mild symptoms and were not treated. CNDA course was progressive (55%) or relapsing (45%), and 93% of patients still walked after a mean disease duration of 11 years. CONCLUSION: Chronic neuropathies with anti-disialosyl ganglioside IgM antibodies have a recognizable phenotype, are mostly intravenous immunoglobulins-responsive and present with a good outcome in a majority of cases.


Assuntos
Imunoglobulinas Intravenosas , Doenças do Sistema Nervoso Periférico , Masculino , Humanos , Feminino , Imunoglobulina M , Estudos Retrospectivos , Gangliosídeos
4.
Clin Neurophysiol ; 133: 20-28, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34800836

RESUMO

OBJECTIVE: This study was undertaken to establish by a multicentric approach the reliability of a new technique evaluating motor axon excitability. METHODS: The minimal threshold, the lowest stimulus intensity allowing a maximal response by 1 mA increments (iUP) and then by 0.1 mA adjustments (iMAX) were prospectively derived from three nerves (median, ulnar, fibular) in four university centers (Liège, Marseille, Fraiture, Nice). iMAX procedure was applied in 28 healthy volunteers (twice) and 32 patients with Charcot-Marie-Tooth (CMT1a), chronic inflammatory demyelinating polyneuropathy (CIDP), Guillain-Barré syndrome (SGB) or axonal neuropathy. RESULTS: Healthy volunteers results were not significantly different between centers. Correlation coefficients between test and retest were moderate (> 0.5). Upper limits of normal were established using the 95th percentile. Comparison of volunteers and patient groups indicated significant increases in iMAX parameters especially for the CMT1a and CIDP groups. In CMT1a, iMAX abnormalities were homogeneous at the three stimulation sites, which was not the case for CIDP. CONCLUSIONS: The iMAX procedure is reliable and allows the monitoring of motor axon excitability disorders. SIGNIFICANCE: The iMAX technique should prove useful to monitor motor axonal excitability in routine clinical practice as it is a fast, non-invasive procedure, easily applicable without specific software or devices.


Assuntos
Axônios/fisiologia , Nervo Mediano/fisiologia , Neurônios Motores/fisiologia , Condução Nervosa/fisiologia , Nervo Fibular/fisiologia , Nervo Ulnar/fisiologia , Adulto , Idoso , Doença de Charcot-Marie-Tooth/fisiopatologia , Feminino , Síndrome de Guillain-Barré/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Estudos Prospectivos , Adulto Jovem
5.
J Neuromuscul Dis ; 9(1): 83-93, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34459413

RESUMO

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common myopathies in adults, displaying a progressive, frequently asymmetric involvement of a typical muscles' pattern. FSHD is associated with epigenetic derepression of the polymorphic D4Z4 repeat on chromosome 4q, leading to DUX4 retrogene toxic expression in skeletal muscles. Identifying biomarkers that correlate with disease severity would facilitate clinical management and assess potential FSHD therapeutics' efficacy. OBJECTIVES: This study purpose was to analyze serum cytokines to identify potential biomarkers in a large cohort of adult patients with FSHD. METHODS: We retrospectively measured the levels of 20 pro-inflammatory and regulatory cytokines in sera from 100 genetically confirmed adult FSHD1 patients. Associations between cytokine concentrations and various clinical scores were investigated. We then measured serum and muscle interleukin 6 (IL-6) levels in a validated FSHD-like mouse model, ranging in severity and DUX4 expression. RESULTS: IL-6 was identified as the only cytokine with a concentration correlating with several clinical severity and functional scores, including Clinical Severity Score, Manual Muscle Testing sum score, Brooke and Vignos scores. Further, FSHD patients displayed overall IL-6 levels more than twice high as control, and patients with milder phenotypes exhibited lower IL-6 serum concentration than those with severe muscular weakness. Lastly, an FSHD-like mouse model analysis confirmed that IL-6 levels positively correlate with disease severity and DUX4 expression. CONCLUSIONS: Serum IL-6, therefore, shows promise as a serum biomarker of FSHD severity in a large cohort of FSHD1 adult patients.


Assuntos
Interleucina-6/sangue , Distrofia Muscular Facioescapuloumeral/sangue , Distrofia Muscular Facioescapuloumeral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
8.
Muscle Nerve ; 63(1): 46-51, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32939798

RESUMO

INTRODUCTION: Nerve ultrasound has been used increasingly in clinical practice as a complementary test for diagnostic assessment of neuropathies, but nerve biopsy remains invaluable in certain cases. The aim of this study was to compare ultra-high-frequency ultrasound (UHF-US) to histologic findings in progressive polyneuropathies. METHODS: Ten patients with severe, progressive neuropathies underwent ultrasound evaluation of the sural nerve before nerve biopsy. Ultrasound data were compared with histologic results in a retrospective manner. RESULTS: Sural nerves were easily identified on UHF-US. Nerve hyperechogenicity correlated with inflammatory infiltrates on biopsy. Nerve fascicles could be identified and measured on ultrasound in the majority of patients. DISCUSSION: Hyperechogenicity on UHF-US may be a marker of nerve inflammation in neuropathies. Furthermore, the UHF-US probe allows for evaluation of sensory nerves in spite of their small size, providing valuable information on their size and on their internal structure.


Assuntos
Neuropatias Diabéticas/patologia , Procedimentos Neurocirúrgicos , Nervo Sural/patologia , Ultrassonografia , Adulto , Idoso , Biópsia/métodos , Neuropatias Diabéticas/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos
9.
Muscle Nerve ; 63(3): 396-401, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33094863

RESUMO

BACKGROUND: Mutations in the GNE gene have been so far described as predominantly associated with distal lower-limb myopathies. Recent reports describe mutations in this gene in patients with peripheral neuropathy and motor neuron disease. METHODS: We describe three patients displaying motor neuropathy in association with GNE mutations. Clinical, electrophysiological, imaging, pathological, and genetic data are presented in a retrospective manner. RESULTS: The three patients had different phenotypes, ranging from mildly progressive lower limb weakness to a rapidly progressive 4-limb weakness. Genetic testing revealed GNE gene mutations in all patients; of those mutations, p.(His186Arg) has not been previously reported. All patients showed evidence of axonal motor nerve involvement on electrodiagnostic examination and/or muscle biopsy. CONCLUSIONS: Nerve involvement associated with GNE gene mutations may be an underdiagnosed pathology and may influence clinical presentation and disease progression.


Assuntos
Complexos Multienzimáticos/genética , Músculo Esquelético/patologia , Polineuropatias/genética , Potenciais de Ação , Adulto , Progressão da Doença , Miopatias Distais/genética , Eletrodiagnóstico , Eletromiografia , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/inervação , Mutação , Fenótipo , Polineuropatias/patologia , Polineuropatias/fisiopatologia , Recrutamento Neurofisiológico , Tomografia Computadorizada por Raios X
10.
Blood ; 136(21): 2428-2436, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32959046

RESUMO

CANOMAD (chronic ataxic neuropathy, ophthalmoplegia, immunoglobulin M [IgM] paraprotein, cold agglutinins, and disialosyl antibodies) is a rare syndrome characterized by chronic neuropathy with sensory ataxia, ocular, and/or bulbar motor weakness in the presence of a monoclonal IgM reacting against gangliosides containing disialosyl epitopes. Data regarding associated hematologic malignancies and effective therapies in CANOMAD are scarce. We conducted a French multicenter retrospective study that included 45 patients with serum IgM antibodies reacting against disialosyl epitopes in the context of evocating neurologic symptoms. The main clinical features were sensitive symptoms (ataxia, paresthesia, hypoesthesia; n = 45, 100%), motor weakness (n = 18, 40%), ophthalmoplegia (n = 20, 45%), and bulbar symptoms (n = 6, 13%). Forty-five percent of the cohort had moderate to severe disability (modified Rankin score, 3-5). Cold agglutinins were identified in 15 (34%) patients. Electrophysiologic studies showed a demyelinating or axonal pattern in, respectively, 60% and 27% of cases. All patients had serum monoclonal IgM gammopathy (median, 2.6 g/L; range, 0.1-40 g/L). Overt hematologic malignancies were diagnosed in 16 patients (36%), with the most frequent being Waldenström macroglobulinemia (n = 9, 20%). Forty-one patients (91%) required treatment of CANOMAD. Intravenous immunoglobulins (IVIg) and rituximab-based regimens were the most effective therapies with, respectively, 53% and 52% of partial or better clinical responses. Corticosteroids and immunosuppressive drugs were largely ineffective. Although more studies are warranted to better define the optimal therapeutic sequence, IVIg should be proposed as the standard of care for first-line treatment and rituximab-based regimens for second-line treatment. These compiled data argue for CANOMAD to be included in neurologic monoclonal gammopathy of clinical significance.


Assuntos
Linfócitos B/efeitos dos fármacos , Paraproteinemias/tratamento farmacológico , Rituximab/uso terapêutico , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ataxia/tratamento farmacológico , Ataxia/etiologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Linfócitos B/patologia , Crioglobulinas/análise , Feminino , França/epidemiologia , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/imunologia , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oftalmoplegia/tratamento farmacológico , Oftalmoplegia/etiologia , Paraproteinemias/sangue , Paraproteinemias/imunologia , Paraproteinemias/terapia , Parestesia/tratamento farmacológico , Parestesia/etiologia , Estudos Retrospectivos , Síndrome , Macroglobulinemia de Waldenstrom/sangue , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Macroglobulinemia de Waldenstrom/imunologia
11.
Clin Neurophysiol ; 131(9): 2209-2215, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32707479

RESUMO

OBJECTIVE: Motor unit number index (MUNIX) is proposed to monitor neuromuscular disorders. Our objective is to determine the intra-individual variability over time of the MUNIX. METHODS: In 11 different hospital centres, MUNIX was assessed twice, at least 3 months apart (range 90-360 days), in tibialis anterior (TA), abductor pollicis brevis (APB), abductor digiti minimi (ADM) and deltoid muscles in 118 healthy subjects. MUNIX sum score 2, 3 and 4 were respectively the sum of the MUNIX of the TA and ADM, of the TA, APB and ADM and of the TA, APB, ADM and deltoid muscles. RESULTS: The repeatability of the MUNIX was better for sum scores than for single muscle recordings. The variability of the MUNIX was independent of sex, age, interval between measurements and was lower for experienced than non-experienced operators. The 95th percentile of the coefficient of variability of the MUNIX sum score 2, 3 and 4 were respectively 22%, 18% and 15% for experienced operators. CONCLUSIONS: The MUNIX technique must be performed by experienced operators on several muscles to reduce its variability and improve its reliability. SIGNIFICANCE: A variation of the MUNIX sum score ≥20% can be interpreted as a significant change of muscle innervation.


Assuntos
Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Recrutamento Neurofisiológico/fisiologia , Adulto , Idoso , Eletromiografia/métodos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/fisiopatologia , Reprodutibilidade dos Testes , Adulto Jovem
12.
J Neurol ; 266(9): 2277-2285, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175432

RESUMO

OBJECTIVES: High-frequency ultrasound (HFUS 18-20 MHz) performed on patients with chronic inflammatory demyelinating polyneuropathy (CIDP) shows a focal enlargement, particularly in the proximal segments of upper-arm motor nerves. Ultrahigh frequency ultrasound (UHFUS 30-70 MHz), having a higher spatial resolution, enables a better characterization of nerve structures. The aim of this study was to compare the two ultrasound probes in the evaluation of motor nerve characteristics in CIDP patients. METHODS: Eleven patients with definite or probable CIDP underwent an ultrasound evaluation of median and ulnar nerves, bilaterally. Nerve and fascicle cross-sectional area (CSA), vascularization, and echogenicity were assessed. RESULTS: Nerve and fascicle CSA were increased in the proximal segments, especially in the median nerve, in 9/11 patients and in 10/11 patients at the HFUS and UHFUS evaluations, respectively. A statistically significant difference between CSA values obtained with the two probes was found only for fascicle values. UHFUS allowed for a more precise estimation of fascicle size and number than the HFUS. We were able to identify nerve vascularization in 4/11 patients at UHFUS only. CONCLUSION: UHFUS gives more detailed information on the changes in the internal nerve structure in CIDP patients. In particular, it permits to better characterize fascicle size and morphology, and to have a precise estimation of their number. Its frequency range also allows to evaluate nerve vascularization. SIGNIFICANCE: Ultrasound evaluation could become an adjunctive diagnostic tool for CIDP. Further studies are needed to validate the examined parameters as biomarkers for the evaluation and follow-up of CIDP patients.


Assuntos
Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia , Terapia por Ultrassom/métodos , Ultrassonografia Doppler/métodos , Adulto , Idoso , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/normas , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Nervo Mediano/fisiologia , Pessoa de Meia-Idade , Nervo Ulnar/diagnóstico por imagem , Nervo Ulnar/fisiologia , Terapia por Ultrassom/normas , Ultrassonografia Doppler/normas
13.
Neurology ; 92(19): e2273-e2285, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30979860

RESUMO

OBJECTIVE: To compare the clinical features of patients showing a classical phenotype of facioscapulohumeral muscular dystrophy (FSHD) with genetic and epigenetic characteristics of the FSHD1 and FSHD2 loci D4Z4 and SMCHD1. METHODS: This is a national multicenter cohort study. We measured motor strength, motor function, and disease severity by manual muscle testing sumscore, Brooke and Vignos scores, clinical severity score (CSS), and age-corrected CSS, respectively. We correlated these scores with genetic (D4Z4 repeat size and haplotype; SMCHD1 variant status) and epigenetic (D4Z4 methylation) parameters. RESULTS: We included 103 patients: 54 men and 49 women. Among them, we identified 64 patients with FSHD1 and 20 patients with FSHD2. Seven patients had genetic and epigenetic characteristics of FSHD1 and FSHD2, all carrying repeats of 9-10 D4Z4 repeat units (RU) and a pathogenic SMCHD1 variant. In the remaining patients, FSHD was genetically excluded or remained unconfirmed. All clinically affected SMCHD1 mutation carriers had a D4Z4 repeat of 9-16 RU on a disease permissive 4qA haplotype. These patients are significantly more severely affected by all clinical scales when compared to patients with FSHD1 with upper-sized FSHD1 alleles (8-10 RU). CONCLUSION: The overlap between FSHD1 and FSHD2 patients in the 9-10 D4Z4 RU range suggests that FSHD1 and FSHD2 form a disease continuum. The previously established repeat size threshold for FSHD1 (1-10 RU) and FSHD2 (11-20 RU) needs to be reconsidered. CLINICALTRIALSGOV IDENTIFIER: NCT01970735.


Assuntos
Metilação de DNA , Força Muscular/fisiologia , Distrofia Muscular Facioescapuloumeral/diagnóstico , Mutação , Adulto , Alelos , Proteínas Cromossômicas não Histona/genética , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Muscular Facioescapuloumeral/genética , Distrofia Muscular Facioescapuloumeral/fisiopatologia , Fenótipo , Índice de Gravidade de Doença
14.
BMC Neurol ; 18(1): 101, 2018 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-30031375

RESUMO

BACKGROUND: Miller Fisher syndrome (MFS) and Bickerstaff's Brainstem Encephalitis (BBE) share some clinical features and a common immunological profile characterized by anti-GQ1b antibodies. Some MFS patients overlap with Guillain-Barré syndrome (GBS) or BBE. We report a patient with MFS, BBE, and axonal GBS overlap in whom serial electrophysiological studies showed persistent motor conduction blocks (CBs). CASE PRESENTATION: A 61-year-old man acutely developed ophtalmoparesis, ataxia and areflexia suggesting MFS. Paresthesias, severe weakness, and drowsiness rapidly developed indicating an overlap with BBE and GBS. Preceding infection with Mycoplasma Pneumoniae and anti-GQ1b antibodies were detected. On day 4, nerve conduction study showed reduced or non-recordable compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) without demyelinating features, indicating the electrodiagnosis of acute motor and sensory axonal neuropathy and suggesting a poor prognosis. Intravenous immunoglobulins (IVIg) were given but clinical status worsened to ophthalmoplegia, tetraplegia and coma needing mechanical ventilation. A second IVIg course was given and the patient was weaned off ventilation on day 41 and transferred to rehabilitation on day 57 with partial resolution of the ophthalmoplegia and limited recovery of muscle strength. Electrophysiology showed, after 10 weeks, greatly improved distal CMAP amplitudes suggesting the resolution of distal CBs while CBs in intermediate and proximal nerve segments emerged. CBs unusually persisted for four to 6 months without development of abnormal temporal dispersion. A third IVIg course was started on day 179 and the resolution of CBs mirrored the clinical improvement. CONCLUSIONS: GQ1b gangliosides are expressed in the nodal region of oculomotor nerves, muscle spindle afferents, peripheral nerves and possibly in the brainstem reticular formation. Anti-GQ1b antibodies may explain the complex symptomatology and the overlap between MFS, BBE, and GBS. CBs that persisted and recovered without the development of temporal dispersion suggest that weakness was due to a sustained, antibody-mediated, attack at the nodal region inducing a non-demyelinating conduction failure as expression of an acute onset, long lasting, nodopathy. Serial electrophysiological studies allowed not only to understand the underlying pathophysiology and formulate a more correct prognosis but also to guide the treatment.


Assuntos
Encefalite , Síndrome de Guillain-Barré , Síndrome de Miller Fisher , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Clin Invest ; 127(4): 1531-1545, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28263188

RESUMO

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant neuromuscular disorder that is characterized by extreme variability in symptoms, with females being less severely affected than males and presenting a higher proportion of asymptomatic carriers. The sex-related factors involved in the disease are not known. Here, we have utilized myoblasts isolated from FSHD patients (FSHD myoblasts) to investigate the effect of estrogens on muscle properties. Our results demonstrated that estrogens counteract the differentiation impairment of FSHD myoblasts without affecting cell proliferation or survival. Estrogen effects are mediated by estrogen receptor ß (ERß), which reduces chromatin occupancy and transcriptional activity of double homeobox 4 (DUX4), a protein whose aberrant expression has been implicated in FSHD pathogenesis. During myoblast differentiation, we observed that the levels and activity of DUX4 increased progressively and were associated with its enhanced recruitment in the nucleus. ERß interfered with this recruitment by relocalizing DUX4 in the cytoplasm. This work identifies estrogens as a potential disease modifier that underlie sex-related differences in FSHD by protecting against myoblast differentiation impairments in this disease.


Assuntos
Estradiol/fisiologia , Estrogênios/fisiologia , Proteínas de Homeodomínio/metabolismo , Distrofia Muscular Facioescapuloumeral/metabolismo , Mioblastos/fisiologia , Diferenciação Celular , Células Cultivadas , Receptor beta de Estrogênio/metabolismo , Expressão Gênica , Humanos , Distrofia Muscular Facioescapuloumeral/patologia , Transporte Proteico , Ativação Transcricional
16.
Brain Stimul ; 8(4): 795-800, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25732371

RESUMO

BACKGROUND: In previous studies, rTMS has been successfully employed to interfere with the right posterior parietal cortex (rPPC) inducing neglect-like behavior in healthy subjects. Several studies have shown that the use of tools can modulate the boundaries between near and far space: indeed when far space is reached by the stick, far space can be remapped as near. OBJECTIVE: The aim of the present study was to investigate whether once that rTMS on the rPPC has selectively induced neglect-like bias in the near space (but not in the far space), neglect can appears also in the far space when the subjects used a tool to perform the task. METHODS: Fifteen right-handed healthy subjects executed a line length judgment task in two different spatial positions (60 cm: near space and 120 cm: far space), with or without rPPC on-line rTMS. In the far space condition, subjects performed the perceptual task while holding or not a tool. RESULTS: During rTMS, visuospatial performance significantly shifted toward right when the task was performed in the near space and in the far space when the tool was used. No significant effect was found when rTMS was delivered in the far space condition without tool use. CONCLUSIONS: Our results demonstrate that the application of rTMS on rPPC, specifically affect the representation of near space because it caused neglect both when the subjects acted in the near space and when they acted in a far space that was remapped as near by the use of a tool.


Assuntos
Lobo Parietal/fisiologia , Transtornos da Percepção/etiologia , Transtornos da Percepção/psicologia , Percepção Espacial , Estimulação Magnética Transcraniana , Adulto , Feminino , Voluntários Saudáveis/psicologia , Humanos , Masculino , Adulto Jovem
17.
Funct Neurol ; 29(3): 189-93, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25473739

RESUMO

Several studies have shown that transcranial direct current stimulation (tDCS) is able to enhance performances on verbal and visual working memory (WM) tasks. Available evidence points to the right dorsolateral prefrontal cortex (DLPFC) as a critical area in visual WM, but to date direct comparisons of the effects obtained by stimulating the left versus the right DLPFC in the same subject are lacking. Our aim was to determine whether tDCS over the right DLPFC can differently affect performance as compared with left DLPFC stimulation. Ten healthy subjects performed a memory-guided visuospatial task in three conditions: baseline, during anodal stimulation applied over the right and during anodal stimulation applied over the left DLPFC. All the subjects also underwent a sham stimulation as control. Our results show that only active stimulation over the right DLPFC is able to increase performance when compared to the other conditions. Our findings confirm the crucial role played by the right DLPFC in spatial WM tasks.


Assuntos
Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiologia , Memória Espacial/fisiologia , Estimulação Transcraniana por Corrente Contínua , Adulto , Feminino , Lateralidade Funcional , Humanos , Masculino , Percepção Visual/fisiologia , Adulto Jovem
18.
Clin Neurophysiol ; 125(9): 1840-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24472614

RESUMO

OBJECTIVE: To evaluate the effects of transcranial direct current stimulation (tDCS) on esophageal peristalsis in patients with gastroesophageal reflux disease (GERD). METHODS: Patients with GERD preliminary diagnosis were included in a randomized double-blind sham-controlled study. Esophageal manometry was performed before and during transcranial direct current stimulation (tDCS) of the right precentral cortex. Half of patients were randomly assigned to anodal, half to sham stimulation. Distal waves amplitude and pathological waves percentage were measured, after swallowing water boli, for ten subsequent times. Last, a 24h pH-bilimetry was done to diagnose non-erosive reflux disease (NERD) or functional heartburn (FH). The values obtained before and during anodal or sham tDCS were compared. RESULTS: Sixty-eight patients were enrolled in the study. Distal waves mean amplitude increased significantly only during anodal tDCS in NERD (p=0.00002) and FH subgroups (p=0.008) while percentage of pathological waves strongly decreased only in NERDs (p=0.002). CONCLUSIONS: Transcranial stimulation can influence cortical control of esophageal motility and improve pathological motor pattern in NERD and FH but not in erosive reflux disease (ERD) patients. SIGNIFICANCE: Pathophysiological processes in GERD are not only due to peripheral damage but to central neural control involvement as well. In ERD patients dysfunctions of the cortico-esophageal circuit seem to be more severe and may affect central nervous system physiology.


Assuntos
Transtornos da Motilidade Esofágica/fisiopatologia , Esôfago/fisiopatologia , Refluxo Gastroesofágico/fisiopatologia , Estimulação Transcraniana por Corrente Contínua , Adulto , Idoso , Método Duplo-Cego , Eletrodos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Manometria , Pessoa de Meia-Idade
19.
Headache ; 51(5): 726-33, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21521207

RESUMO

OBJECTIVE: An imbalance between activity of inhibitory and facilitatory intracortical circuits could play a central role in migraine etiology. We used input-output curves to achieve further information about intracortical excitability of motor cortex in migraine with aura. METHODS: Input-output curves were measured in the right abductor pollicis brevis muscle at rest in 12 patients suffering from migraine with aura and 8 healthy subjects. Stimuli were delivered at intensity ranging from 100% to 160% of resting motor threshold with 10-second inter-stimulus intervals. Seven patients were studied before and during treatment with levetiracetam. RESULTS: Results showed a greater motor-evoked potential amplitude in response to increasing intensity of stimuli in patients compared to controls (P < .02). This increased facilitatory effect was abolished by levetiracetam (P < .005). CONCLUSIONS: Our findings support the hypothesis of an interictal cortical hyper-responsivity in migraine patients that appears to be normalized by levetiracetam. This effect could support the potential therapeutic role of levetiracetam in migraine with aura prevention.


Assuntos
Potencial Evocado Motor/fisiologia , Enxaqueca com Aura/fisiopatologia , Córtex Motor/fisiopatologia , Transmissão Sináptica/fisiologia , Adulto , Feminino , Glutamina/metabolismo , Humanos , Masculino , Enxaqueca com Aura/metabolismo , Estimulação Magnética Transcraniana
20.
J Headache Pain ; 12(2): 185-91, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21350791

RESUMO

Evidence by functional imaging studies suggests the role of left dorsolateral prefrontal cortex (DLPFC) in the inhibitory control of nociceptive transmission system. Repetitive transcranial magnetic stimulation (rTMS) is able to modulate pain response to capsaicin. In the present study, we evaluated the effect of DLPFC activation (through rTMS) on nociceptive control in a model of capsaicin-induced pain. The study was performed on healthy subjects that underwent capsaicin application on right or left hand. Subjects judged the pain induced by capsaicin through a 0-100 VAS scale before and after 5 Hz rTMS over left and right DLPFC at 10 or 20 min after capsaicin application in two separate groups (8 subjects each). Left DLPFC-rTMS delivered either at 10 and 20 min after capsaicin application significantly decreased spontaneous pain in both hands. Right DLPFC rTMS showed no significant effect on pain measures. According to these results, stimulation of left DLPFC seems able to exert a bilateral control on pain system, supporting the critical antinociceptive role of such area. This could open new perspectives to non-invasive brain stimulation protocols of alternative target area for pain treatment.


Assuntos
Inibição Neural/fisiologia , Manejo da Dor , Dor/fisiopatologia , Córtex Pré-Frontal/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto , Capsaicina/farmacologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/induzido quimicamente , Medição da Dor/métodos , Córtex Pré-Frontal/efeitos da radiação
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