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1.
Life Sci ; 271: 119202, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33577853

RESUMO

BACKGROUND: Diabetic neuropathy is one of the most common microvascular complication of diabetes. It is associated with neuronal dysfunction and pain. Paeonol is an important natural product reported for its antioxidant, anti-inflammatory and antidiabetic activities. AIM: The present research was planned to study effect of paeonol in diabetic peripheral neuropathy in rats. METHODS: Diabetes was induced in Sprague Dawley rats by using Streptozotocin (55 mg/kg, i.p.). After six weeks, diabetic animals were treated daily with paeonol at a dose of 50, 100 and 200 mg/kg for four weeks. At the end of the treatment, plasma glucose, mechanical allodynia, mechanical hyperalgesia, thermal hyperalgesia and nerve conduction velocities were recorded. Oxidative stress parameters were studied in sciatic nerve. Histopathology study of sciatic nerve, NF-κB and MCP-1 expression were also studied at the end of study. KEY FINDINGS: Paeonol treatment significantly lowered the plasma glucose levels, mechanical allodynia, mechanical hyperalgesia and thermal hyperalgesia as compared to diabetic control group. Paeonol treatment also enhanced the motor and sensory nerve conduction velocity. Paeonol treated diabetic animals showed significant changes in oxidative stress parameters. Histopathology study indicated that paeonol treatment prevented the neuronal damage, lowered demyelination and leukocyte infiltration. NF-κB and MCP-1 expression was significantly decreased in sciatic nerve of diabetic animals treated with paeonol. SIGNIFICANCE: Results of the present study indicate that paeonol may be considered as effective option for management of diabetic neuropathy.


Assuntos
Acetofenonas/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Condução Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Acetofenonas/farmacologia , Animais , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Masculino , Condução Nervosa/fisiologia , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
2.
Muscle Nerve ; 63(4): 472-476, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33399235

RESUMO

BACKGROUND: Precise placement of stimulating and recording electrodes is vital when performing nerve conduction studies (NCSs). In this study, we aimed to determine whether ultrasonography (US) was more precise in localizing the superficial radial nerve (SRN), dorsal ulnar cutaneous nerve (DUCN), ulnar nerve (UN) crossing the cubital tunnel, and radial nerve (RN) crossing the spiral groove (SG) compared to conventional techniques. METHODS: Thirty healthy young subjects (15 male) were recruited. Each subject underwent both landmark-based and US-guided NCS. Onset latencies and amplitudes of compound motor action potentials (CMAPs) and sensory nerve action potentials (SNAPs), and stimulation levels (ie, intensity × duration) required to obtain maximal CMAP amplitudes were compared between the two techniques. RESULTS: The mean CMAP amplitudes of the UN above the cubital tunnel (9.55 ± 1.96 vs 8.96 ± 1.94 mV, P = .030), UN below the cubital tunnel (10.11 ± 2.07 vs 9.37 ± 1.95 mV, P < .001), and RN below the SG (5.21 ± 1.56 vs 4.34 ± 1.03 mV, P < .001) were significantly greater using US-guided NCSs compared to landmark-based NCSs. The mean onset latency of the DUCN was significantly shorter using US-guided NCSs (1.49 ± 0.15 vs 1.57 ± 0.14 ms, P = .020). The required stimulation level in the UN and RN was significantly lower using US-guided NCSs. CONCLUSIONS: When performing NCSs, US guidance provides a more precise localization of the stimulator and electrodes for the DUCN, UN, and RN, while providing comparable localization for the SRN, compared to landmark-based techniques.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Exame Neurológico , Nervo Ulnar/diagnóstico por imagem , Ultrassonografia , Potenciais de Ação/fisiologia , Adulto , Eletrodiagnóstico/métodos , Feminino , Guias como Assunto , Humanos , Masculino , Condução Nervosa/fisiologia , Exame Neurológico/métodos , Exame Neurológico/normas , Ultrassonografia/métodos , Ultrassonografia/normas
3.
Muscle Nerve ; 63(4): 538-545, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33433915

RESUMO

BACKGROUND: Several studies of patients with polyneuropathy failed to show differences between patients with and without pain. In the current study, we aimed to explore the association between neuropathic symptoms, mainly pain, and polyneuropathy characteristics. METHODS: A prospective cross-sectional study recruiting 151 patients with non-diabetic polyneuropathy was performed between November 2016 and May 2017. A total of 38 patients with chronic inflammatory demyelinating neuropathy were excluded. Patients underwent clinical, electrophysiological and functional assessments of their polyneuropathy. Polyneuropathy characteristics were compared depending on the presence and severity of neuropathic symptoms. RESULTS: The presence and the severity of weakness were associated with a more severe neuropathy as measured by clinical, electrophysiological and functional assessments, while the presence of pain was associated with higher sural amplitudes, and the severity of pain showed a curvilinear association with neuropathy severity. CONCLUSIONS: Our study shows a novel finding of a curvilinear association between pain and polyneuropathy severity.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Dor/fisiopatologia , Polineuropatias/complicações , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Adulto , Idoso , Estudos Transversais , Neuropatias Diabéticas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Dor/complicações , Polineuropatias/diagnóstico , Polineuropatias/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/complicações , Estudos Prospectivos
4.
Muscle Nerve ; 63(4): 546-552, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33452679

RESUMO

BACKGROUND: The most common subtypes of Guillain-Barré syndrome (GBS) are acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). In the first days after the onset of weakness, standard nerve conduction studies (NCS) may not distinguish GBS subtypes. Reduced nerve excitability may be an early symptom of nerve dysfunction, which can be determined with the compound muscle action potential (CMAP) scan. The aim of this study was to explore whether early changes in motor nerve excitability in GBS patients are related to various subtypes. METHODS: Prospective case-control study in 19 GBS patients from The Netherlands and 22 from Bangladesh. CMAP scans were performed within 2 days of hospital admission and NCS 7-14 days after onset of weakness. CMAP scans were also performed in age- and country-matched controls. RESULTS: CMAP scan patterns of patients who were classified as AMAN were distinctly different compared to the CMAP scan patterns of the patients who were classified as AIDP. The most pronounced differences were found in the stimulus intensity parameters. CONCLUSIONS: CMAP scans made at hospital admission demonstrate several characteristics that can be used as an early indicator of GBS subtype.


Assuntos
Tecido Nervoso/fisiopatologia , Condução Nervosa/fisiologia , Sistema Nervoso Periférico/diagnóstico por imagem , Sistema Nervoso Periférico/fisiopatologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Países Baixos , Exame Neurológico/métodos
5.
Muscle Nerve ; 63(3): 371-383, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33340120

RESUMO

BACKGROUND: To collect preliminary data on the effects of mexiletine on cortical and axonal hyperexcitability in sporadic amyotrophic lateral sclerosis (ALS) in a phase 2 double-blind randomized controlled trial. METHODS: Twenty ALS subjects were randomized to placebo and mexiletine 300 or 600 mg daily for 4 wk and assessed by transcranial magnetic stimulation and axonal excitability studies. The primary endpoint was change in resting motor threshold (RMT). RESULTS: RMT was unchanged with 4 wk of mexiletine (combined active therapies) as compared to placebo, which showed a significant increase (P = .039). Reductions of motor evoked potential (MEP) amplitude (P = .013) and accommodation half-time (P = .002), secondary outcome measures of cortical and axonal excitability, respectively, were also evident at 4 wk on mexiletine. CONCLUSIONS: The relative stabilization of RMT in the treated subjects was unexpected and could be attributed to unaccounted sources of error or chance. However, a possible alternative cause is neuromodulation preventing an increase. The change in MEP amplitude and accommodation half-time supports the reduction of cortical and axonal hyperexcitability with mexiletine.


Assuntos
Esclerose Amiotrófica Lateral/tratamento farmacológico , Axônios , Excitabilidade Cortical , Mexiletina/uso terapêutico , Bloqueadores do Canal de Sódio Disparado por Voltagem/uso terapêutico , Adulto , Idoso , Esclerose Amiotrófica Lateral/fisiopatologia , Método Duplo-Cego , Eletrodiagnóstico , Eletromiografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Dados Preliminares , Estimulação Magnética Transcraniana
6.
J Neurol Sci ; 420: 117263, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33321326

RESUMO

BACKGROUND: The COVID-19 pandemic caused by SARS-COV-2 began in Wuhan, China in December 2019. Reports of COVID-19 with central (CNS) and peripheral nervous (PNS) system manifestations are emerging. In this systematic review, we compared and summarized the demographics, clinical features, Brighton criteria, immunological and laboratory findings with a focus on modified Erasmus GBS Outcome Score (mEGOS) in SARS-CoV-2 patients with GBS and its variants. METHODS: Based on PRISMA guidelines, we searched three databases (PubMed, Scopus, and Google Scholar) for studies on COVID-19 and GBS between December 1, 2019 to July 15, 2020. For descriptive analysis, we studied two groups with: 1) acute inflammatory demyelinating polyradiculoneuropathy (AIDP) variant, and 2) Non-AIDP/Other variants. We compared mEGOS scores for patients in both groups along with other key clinical features. RESULTS: Of the 50 GBS cases identified from 37 studies, 33 (66%) had acute inflammatory demyelinating polyradiculopolyneuropathy (AIDP) while 17 (34%) were of other (non-AIDP) variants. There mEGOS scores did not differ between AIDP patients and AMAN/AMSAN patients. Majority of the AIDP (66.7%) and AMAN/AMSAN (57.2%) patients belonged to Brighton level 1 indicating maximum diagnostic certainty. CONCLUSION: To our knowledge, this is among the first reviews that includes GBS variants and the clinical prediction tool mEGOS for prognostication in COVID-19 patients. Further research is needed to assess whether IVIG is preferable over plasmapheresis in this population of GBS patients. It would also be crucial to follow these patients over time to identify the long-term disability as well as treatment outcomes.


Assuntos
/complicações , Síndrome de Guillain-Barré/etiologia , /fisiopatologia , Síndrome de Guillain-Barré/fisiopatologia , Humanos , Condução Nervosa/fisiologia
7.
PLoS One ; 15(12): e0242406, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33320861

RESUMO

INTRODUCTION: Sensory and motor nerve deficits are prevalent in older adults and are associated with loss of functional independence. We hypothesize that chronic kidney disease predisposes to worsening sensorimotor nerve function over time. MATERIALS AND METHODS: Participants were from the Health, Aging and Body Composition Study (N = 1121) with longitudinal data between 2000-01 (initial visit) and 2007-08 (follow-up visit). Only participants with non-impaired nerve function at the initial visit were included. The predictor was presence of CKD (estimated GFR ≤ 60 ml/min/1.73m2) from the 1999-2000 visit. Peripheral nerve function outcomes at 7-year follow-up were 1) Motor: "new" impairments in motor parameters (nerve conduction velocity NCV < 40 m/s or peroneal compound motor action potential < 1 mv) at follow-up, and 2) Sensory: "new" impairment defined as insensitivity to standard 10-g monofilament or light 1.4-g monofilament at the great toe and "worsening" as a change from light to standard touch insensitivity over time. The association between CKD and "new" or "worsening" peripheral nerve impairment was studied using logistic regression. RESULTS: The study population was 45.9% male, 34.3% Black and median age 75 y. CKD participants (15.6%) were older, more hypertensive, higher in BMI and had 2.37 (95% CI 1.30-4.34) fold higher adjusted odds of developing new motor nerve impairments in NCV. CKD was associated with a 2.02 (95% CI 1.01-4.03) fold higher odds of worsening monofilament insensitivity. CKD was not associated with development of new monofilament insensitivity. CONCLUSIONS: Pre-existing CKD leads to new and worsening sensorimotor nerve impairments over a 7-year time period in community-dwelling older adults.


Assuntos
Nervos Periféricos/fisiopatologia , Doenças do Sistema Nervoso Periférico/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Idoso , Envelhecimento , Grupo com Ancestrais do Continente Europeu , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Condução Nervosa/fisiologia , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/fisiopatologia , Fatores de Risco , Autorrelato/estatística & dados numéricos , Limiar Sensorial/fisiologia
8.
Neurology ; 95(19): e2697-e2706, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33055277

RESUMO

OBJECTIVE: To investigate small fiber innervation of the skin and its relationships with clinicometry of autism and peripheral afferents for contact heat-evoked potential (CHEP) and psychophysical measures of thermal thresholds. METHODS: We recruited 32 men with autism (26.5 ± 5.9 years) and conducted small fiber assessments of skin biopsy with quantifying intraepidermal nerve fiber (IENF) density, CHEP, quantitative sensory testing, and large fiber physiology of nerve conduction studies. Results were compared with age-matched controls and analyzed with clinical measures of autism. RESULTS: Patients with autism showed a lower IENF density than controls (5.53 ± 2.09 vs 11.13 ± 3.49 fibers/mm, p < 0.0001). The IENF density was reduced in 17 (53.1%) men with autism classified as skin denervation group. On psychophysics, 9 (28%) men with autism had elevated thermal thresholds, and the warm threshold of the big toe was negatively correlated with IENF density (p = 0.0073), indicating functional impairments of small fiber sensory nerves. IENF density was negatively correlated with CHEP amplitude in autism (p = 0.003), in contrast to the pattern of positive correlation in controls, indicating different processing of nociceptive afferent in autism. Clinically, IENF density was related to distinct tactile symptom patterns in the skin denervation vs normal innervation group, respectively. Furthermore, IENF density was associated with autistic symptoms measured by the Autism Spectrum Quotient in a U-shaped model (p = 0.014). CONCLUSIONS: These observations indicated that a substantial portion of individuals with autism had small fiber pathology, which was associated with tactile and autistic symptoms, providing structural and physiologic evidence for the involvement of peripheral sensory nerves in autism.


Assuntos
Transtorno Autístico/fisiopatologia , Epiderme/patologia , Potenciais Somatossensoriais Evocados/fisiologia , Temperatura Alta , Fibras Nervosas/patologia , Condução Nervosa/fisiologia , Nociceptividade/fisiologia , Adulto , Estudos de Casos e Controles , Eletrodiagnóstico , Epiderme/inervação , Humanos , Masculino , Limiar da Dor , Limiar Sensorial , Adulto Jovem
9.
Medicine (Baltimore) ; 99(39): e22286, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32991431

RESUMO

BACKGROUND: At present, the effect of western-medicine (WM) therapy to treat diabetic peripheral neuropathy (DPN) is limited. Moxibustion is a representative external treatment in traditional Chinese medicine that has been beneficial to DPN. We aim to systematically assess the efficacy and safety of moxibustion in treating DPN, following PRISMA guidelines. METHODS: Eight electronic databases were searched to acquire information on eligible trials published from inception to June 1, 2019. We included randomized controlled trials (RCTs) applying moxibustion therapy with a minimum of 14-days treatment duration for DPN patients compared with placebo, no intervention, or conventional WM interventions. The primary outcomes in our study include the sensory-nerve conduction velocity (SNCV) and motor-nerve conduction velocity (MNCV). We used the Cochrane Collaboration Risk of Bias tool to assess the methodological quality of eligible RCTs. Statistical analyses were conducted using Review Manager 5.3. Risk ratios (RR) and mean differences (MD) were calculated with a 95% confidence interval (CI). The χ test was applied to assess the heterogeneity. RESULTS: In total, 11 RCTs were included that involved 927 DPN patients. Compared with the control group, there was an increase in median MNCV (MD = 6.26, 95% CI 2.64-9.89, Z = 3.39, P = .0007) and peroneal MNCV (MD = 6.45, 95% CI 5.30-7.61, P < .00001). There was also an increase in median SNCV (MD = 6.64, 95% CI 3.25-10.03, P = .0001) and peroneal SNCV (MD = 3. 57, 95% CI 2.06-5.09, Z = 4.63, P < .00001) in the treatment groups. The treatment groups receiving moxibustion therapy indicated a more significant improvement in total effectiveness rate (RR = 0.25, 95% CI 0.18-0.37, Z = 7.16, P < .00001). Toronto Clinical Scoring System indicated a significant decrease in the treatment groups (MD = -2.12, 95% CI -2.82 to 1.43, P < .00001). Only 1 study reported that treatment groups experienced no adverse reactions. The other 10 studies did not mention adverse events. CONCLUSIONS: Moxibustion therapy may be an effective and safe option for DPN patients but needs to be verified in further rigorous studies.


Assuntos
Neuropatias Diabéticas/terapia , Medicina Tradicional Chinesa/métodos , Moxibustão/métodos , Condução Nervosa/efeitos dos fármacos , Adulto , Idoso , Estudos de Casos e Controles , Bases de Dados Factuais , Tratamento Farmacológico/normas , Duração da Terapia , Feminino , Humanos , Masculino , Medicina Tradicional Chinesa/efeitos adversos , Pessoa de Meia-Idade , Moxibustão/efeitos adversos , Condução Nervosa/fisiologia , Nervo Fibular/fisiopatologia , Placebos/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Segurança , Resultado do Tratamento , Ocidente
12.
Diabetes Res Clin Pract ; 166: 108289, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32615278

RESUMO

AIMS: Continuous glucose monitoring (CGM)-derived time-in-range (TIR) of 3.9-10 mmol/L is associated with diabetic retinopathy in type 2 diabetes (T2DM), but its relationship to peripheral nerve function has not been previously investigated. To explore the association between the TIR and nerve conduction study parameters in patients with T2DM, we performed a cross-sectional analysis. METHODS: A total of 740 patients with T2DM were enrolled in this study. All of the participants were divided into tertiles according to the TIR (TIR low: ≤53%; TIR medium: 54-76%; TIR high: ≥77%). Composite Z-scores of nerve conduction velocity (CV), latency, and amplitude were calculated. The linear correlation between the TIR and composite nerve function Z-score was evaluated and risk assessment was analysed using binary logistic regression. RESULTS: The composite Z-score of the CV and amplitude increased with higher TIR and the composite Z-score of latency significantly decreased as the TIR tertiles increased (all P trend < 0.05). After adjusting for age, diabetes duration, height, weight and other confounding factors, higher TIR was associated with a higher composite Z-score of CV (ß = 0.230, P < 0.001), amplitude (ß = 0.099, P = 0.010), and lower composite Z-score of latency (ß = -0.172, P < 0.001). The risk of TIR tertiles and low composite Z-score of CV remained significant even after adjustment of HbA1c (TIR medium: OR = 0.48, P = 0.001; TIR high: OR = 0.41, P < 0.001). CONCLUSIONS: Higher TIR tertiles were independently associated with better peripheral nerve function. CGM-derived TIR may be a promising approach to screen patients for further assessment of possible diabetic peripheral neuropathy.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 2/sangue , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/etiologia , Nervos Periféricos/fisiopatologia , Adulto , Idoso , Glicemia/metabolismo , Automonitorização da Glicemia/normas , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Planejamento de Assistência ao Paciente/normas , Valores de Referência , Fatores de Risco , Fatores de Tempo
13.
Muscle Nerve ; 62(4): 534-540, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32696477

RESUMO

BACKGROUND: In this study, we aimed to investigate the progression of peripheral nervous system involvement in xeroderma pigmentosum group A (XP-A). METHODS: We performed nerve conduction studies in 17 genetically confirmed XP-A patients and conducted follow-ups. Of these patients we also analyzed gray matter volume (GMV) using brain MRI and assessed the severity score of clinical and skin manifestation. RESULTS: We found significant reduction in the motor and sensory nerve action potential amplitude and mild reduction in conduction velocity. These findings were predominant in sensory nerves and the lower limbs, were observed since early childhood, and gradually deteriorated with age. CONCLUSIONS: The electrophysiological characteristics of XP-A patients are consistent with length-dependent axonal polyneuropathy and there is progressive deterioration from early childhood.


Assuntos
Encéfalo/fisiopatologia , Condução Nervosa/fisiologia , Xeroderma Pigmentoso/fisiopatologia , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Imagem por Ressonância Magnética , Masculino , Índice de Gravidade de Doença , Xeroderma Pigmentoso/diagnóstico por imagem , Adulto Jovem
14.
Muscle Nerve ; 62(4): 485-491, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32678460

RESUMO

Guillain-Barré syndrome (GBS) is an inflammatory polyradiculoneuropathy associated with numerous viral infections. Recently, there have been many case reports describing the association between coronavirus disease-2019 (COVID-19) and GBS, but much remains unknown about the strength of the association and the features of GBS in this setting. We reviewed 37 published cases of GBS associated with COVID-19 to summarize this information for clinicians and to determine whether a specific clinical or electrodiagnostic (EDx) pattern is emerging. The mean age (59 years), gender (65% male), and COVID-19 features appeared to reflect those of hospitalized COVID-19 patients early in the pandemic. The mean time from COVID-19 symptoms to GBS symptoms was 11 days. The clinical presentation and severity of these GBS cases was similar to those with non-COVID-19 GBS. The EDx pattern was considered demyelinating in approximately half of the cases. Cerebrospinal fluid, when assessed, demonstrated albuminocytologic dissociation in 76% of patients and was negative for severe acute respiratory distress syndrome-coronavirus-2 (SARS-CoV-2) in all cases. Serum antiganglioside antibodies were absent in 15 of 17 patients tested. Most patients were treated with a single course of intravenous immunoglobulin, and improvement was noted within 8 weeks in most cases. GBS-associated COVID-19 appears to be an uncommon condition with similar clinical and EDx patterns to GBS before the pandemic. Future studies should compare patients with COVID-19-associated GBS to those with contemporaneous non-COVID-19 GBS and determine whether the incidence of GBS is elevated in those with COVID-19.


Assuntos
Betacoronavirus , Encéfalo/diagnóstico por imagem , Infecções por Coronavirus/complicações , Síndrome de Guillain-Barré/etiologia , Condução Nervosa/fisiologia , Pandemias , Pneumonia Viral/complicações , Infecções por Coronavirus/epidemiologia , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/fisiopatologia , Humanos , Imagem por Ressonância Magnética , Pneumonia Viral/epidemiologia , Fatores de Tempo
15.
Neurol Clin ; 38(3): 591-605, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32703471

RESUMO

Please verify term, "alternative". Chronic immune-mediated demyelinating polyneuropathy (CIDP) is a treatable immune-related demyelinating polyneuropathy. Approximately 20% of cases do not respond to first-line therapies; most of these cases are due to alternative diagnoses, although some of them are due to severe CIDP. Unfortunately, a lack of universally accepted diagnostic criteria complicates the course of diagnosis and treatment. This article discusses videos of cases referred to a tertiary medical center for "refractory CIDP" and pitfalls in the diagnosis and management of this condition.


Assuntos
Condução Nervosa/fisiologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia
16.
Neurology ; 95(12): e1745-e1753, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32675082

RESUMO

OBJECTIVE: To validate the diagnostic accuracy of a previously described short sonographic protocol to identify chronic inflammatory neuropathy (CIN), including chronic inflammatory demyelinating polyneuropathy (CIDP), Lewis Sumner syndrome, and multifocal motor neuropathy (MMN), and to determine the added value of nerve ultrasound to detect treatment-responsive patients compared to nerve conduction studies (NCS) in a prospective multicenter study. METHODS: We included 100 consecutive patients clinically suspected of CIN in 3 centers. The study protocol consisted of neurologic examination, laboratory tests, NCS, and nerve ultrasound. We validated a short sonographic protocol (median nerve at forearm, upper arm, and C5 nerve root) and determined its diagnostic accuracy using the European Federation of Neurological Societies/Peripheral Nerve Society criteria of CIDP/MMN (reference standard). In addition, to determine the added value of nerve ultrasound in detecting treatment-responsive patients, we used previously published diagnostic criteria based on clinical, NCS, and sonographic findings and treatment response (alternative reference standard). RESULTS: Sensitivity and specificity of the sonographic protocol for CIN according to the reference standard were 87.4% and 67.3%, respectively. Sensitivity and specificity of this protocol according to the alternative reference standard were 84.6% and 72.8%, respectively, and of NCS 76.1% and 93.4%. With addition of nerve ultrasound, 44 diagnoses of CIN were established compared to 33 diagnoses with NCS alone. CONCLUSIONS: A short sonographic protocol shows high diagnostic accuracy for detecting CIN. Nerve ultrasound is able to detect up to 25% more patients who respond to treatment. CLASSIFICATION OF EVIDENCE: This multicenter study provides Class IV evidence that nerve ultrasound improves diagnosis of CIN.


Assuntos
Polirradiculoneuropatia/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Estudos de Coortes , Eletromiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Ideggyogy Sz ; 73(05-06): 185-188, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32579308

RESUMO

Background and purpose: After carpal tunnel surgery, some patients report complaints such as edema, pain, and numbness. Purpose - The aim of this study was to evaluate autonomic nervous system function in patients with a history of carpal tunnel surgery using sympathetic skin response (SSR). Methods: Thirty three patients (55 ±10 years old) with a history of unilateral operation for carpal tunnel syndrome were included in the study. The SSR test was performed for both hands. Both upper extremities median and ulnar nerve conduction results were recorded. Results: A reduced amplitude (p=0.006) and delayed latency (p<0.0001) were detected in the SSR test on the operated side compared to contralateral side. There was no correlation between SSR and carpal tunnel syndrome severity. Conclusion: Although complex regional pain syndrome does not develop in patients after carpal tunnel surgery, some of the complaints may be caused by effects on the autonomic nervous system.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Síndrome do Túnel Carpal/cirurgia , Resposta Galvânica da Pele/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Idoso , Feminino , Humanos , Masculino , Nervo Mediano , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Complicações Pós-Operatórias , Resultado do Tratamento , Nervo Ulnar/fisiologia , Nervo Ulnar/fisiopatologia
18.
Muscle Nerve ; 62(3): 363-368, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32557710

RESUMO

INTRODUCTION: The main goal of this study was to determine the contribution of the anterior forearm muscles to the compound muscle action potential (CMAP) recorded from the extensor digitorum (ED) after proximal stimulation. METHODS: Twenty-one healthy volunteers and 114 patients with compressive and traumatic radial neuropathies were examined. Stimulation was carried out at six different points: distal third of the upper arm; Erb's point; axilla; medial upper arm; antecubital fossa; and ulnar groove. RESULTS: In the control group, Erb's CMAP area was significantly greater than the distal CMAP area. In compressive neuropathy, there was conduction block, but no change in conduction velocity. There were no differences in Erb's CMAP latencies between the control group and the neuropathies group. DISCUSSION: CMAPs recorded over the ED with stimulation at the brachial plexus represent the sum of the motor unit action potentials of the posterior and anterior forearm muscles.


Assuntos
Potenciais de Ação/fisiologia , Músculo Esquelético/inervação , Condução Nervosa/fisiologia , Nervo Radial/fisiopatologia , Neuropatia Radial/fisiopatologia , Adulto , Estimulação Elétrica , Eletromiografia , Feminino , Antebraço/inervação , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
J Electromyogr Kinesiol ; 53: 102439, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563844

RESUMO

Muscle fibre conduction velocity (MFCV) is a basic physiological parameter biophysically related to the diameter of muscle fibres and properties of the sarcolemma. The aim of this study was to assess the intersession reproducibility of the relation between voluntary force and estimates of average muscle fibre conduction velocity (MFCV) from multichannel high-density surface electromyographic recordings (HDsEMG). Ten healthy men performed six linearly increasing isometric ankle dorsiflexions on two separate experimental sessions, 4 weeks apart. Each session involved the recordings of voluntary force during maximal isometric (MViF) and submaximal ramp contractions at 35-50-70% of MViF. Concurrently, the HDsEMG activity was detected from the tibialis anterior muscle and MFCV estimates were derived in 250-ms epochs. Absolute and relative reproducibility of MFCV initial value (intercept) and rate of change (regression slope) as a function of force were assessed by within-subject coefficient of correlation (CVw) and with intraclass correlation coefficient (ICC). MFCV was positively correlated with voluntary force (R2 = 0.75 ± 0.12) in all individuals and test conditions (P < 0.001). Average CVw for MFCV intercept and slope were of 2.6 ± 2.0% and 11.9 ± 3.2% and ICC values of 0.96 and 0.94, respectively. Overall, MFCV regression coefficients showed a high degree of intersession reproducibility in both absolute and relative terms. These results may have important practical implications in the tracking of training-induced neuromuscular changes and/or in the monitoring of the progress of neuromuscular disorders when a full sEMG signal decomposition is problematic or not possible.


Assuntos
Eletromiografia/métodos , Contração Isométrica/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Condução Nervosa/fisiologia , Adulto , Humanos , Masculino , Músculo Esquelético/fisiologia , Reprodutibilidade dos Testes , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 117(24): 13227-13237, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32482855

RESUMO

Communication and oscillatory synchrony between distributed neural populations are believed to play a key role in multiple cognitive and neural functions. These interactions are mediated by long-range myelinated axonal fiber bundles, collectively termed as white matter. While traditionally considered to be static after development, white matter properties have been shown to change in an activity-dependent way through learning and behavior-a phenomenon known as white matter plasticity. In the central nervous system, this plasticity stems from oligodendroglia, which form myelin sheaths to regulate the conduction of nerve impulses across the brain, hence critically impacting neural communication. We here shift the focus from neural to glial contribution to brain synchronization and examine the impact of adaptive, activity-dependent changes in conduction velocity on the large-scale phase synchronization of neural oscillators. Using a network model based on primate large-scale white matter neuroanatomy, our computational and mathematical results show that such plasticity endows white matter with self-organizing properties, where conduction delay statistics are autonomously adjusted to ensure efficient neural communication. Our analysis shows that this mechanism stabilizes oscillatory neural activity across a wide range of connectivity gain and frequency bands, making phase-locked states more resilient to damage as reflected by diffuse decreases in connectivity. Critically, our work suggests that adaptive myelination may be a mechanism that enables brain networks with a means of temporal self-organization, resilience, and homeostasis.


Assuntos
Sincronização de Fases em Eletroencefalografia/fisiologia , Bainha de Mielina/fisiologia , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Encéfalo/fisiologia , Conectoma , Modelos Neurológicos , Rede Nervosa/citologia , Condução Nervosa/fisiologia , Neuroglia/fisiologia , Primatas , Substância Branca/citologia , Substância Branca/fisiologia
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