RESUMO
We sought to investigate the effects of dopamine on motor cortical plasticity in Parkinson's disease (PD) using a novel interventional transcranial magnetic stimulation protocol that targets spike-timing-dependent plasticity (iTMS). Six patients (3F, mean age 62 years) with mild-moderate PD (mean disease duration 6 years, UPDRS-off 13, UPDRS-on 3, H&Y stage 2, daily levodopa dosage 450 mg) were studied off and on levodopa on separate days. Paired TMS pulses at resting motor threshold with an inter-stimulus interval of 1.5 ms were given over the hand area of the motor cortex for 20 min at 0.2 Hz. Single-pulse motor evoked potential (MEP) amplitude and visually cued simple reaction time (SRT) were measured before and after iTMS. When on levodopa, MEP amplitude increased to 278+/-36% of baseline (p<0.01), and when off levodopa to 157+/-13% of baseline (p=0.02). All patients showed a significantly greater increase in MEP amplitude when on levodopa than off levodopa (p=0.01). SRT was reduced to 95% baseline after iTMS off levodopa (p=0.02), but did not change on levodopa. These findings indicate that motor cortex plasticity to iTMS is preserved in mild-moderate PD. The effects of this spike-timing-related TMS protocol on cortical excitability were consistent and were enhanced by levodopa. The results support the important role of dopamine in regulating synaptic plasticity and justify a larger crossover study to assess the therapeutic effects of iTMS in PD.
Assuntos
Dopamina/metabolismo , Potencial Evocado Motor/fisiologia , Córtex Motor/fisiopatologia , Doença de Parkinson/fisiopatologia , Estimulação Magnética Transcraniana , Aciclovir/análogos & derivados , Idoso , Análise de Variância , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico , Estimulação Elétrica/métodos , Potencial Evocado Motor/efeitos dos fármacos , Feminino , Ácido Glutâmico/análogos & derivados , Ácido Glutâmico/efeitos dos fármacos , Ácido Glutâmico/fisiologia , Humanos , Levodopa/farmacologia , Levodopa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Córtex Motor/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologiaRESUMO
BACKGROUND: Primary writing tremor (PWT) is a task-specific tremor of uncertain origin. There has been debate as to whether PWT represents a variant of essential tremor or a tremulous form of focal dystonia related to writer's cramp. In writer's cramp there is evidence of changes in intracortical inhibition (ICI), as well as cortical motor reorganisation. OBJECTIVE: To study corticomotor organisation and short-latency ICI in a patient with typical task-specific PWT. METHODS: Transcranial magnetic stimulation mapping of the corticomotor representation of the hand and studies of ICI using paired-pulse stimulation were performed in a 47-year-old right-handed woman with a pure task-specific writing tremor. RESULTS: The motor maps for the hand were displaced posteriorly on both sides and reverted to a normal position after treatment with botulinum toxin. Short-latency ICI was reduced for the dominant hand. CONCLUSION: The findings indicate reorganisation and disinhibition of the corticomotor projection to the hand and point to the participation of cortical centres in the origin of PWT.
Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Escrita Manual , Córtex Motor/fisiopatologia , Fármacos Neuromusculares/uso terapêutico , Tremor/fisiopatologia , Tremor/terapia , Mapeamento Encefálico , Eletroencefalografia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Estimulação Magnética Transcraniana , Tremor/psicologiaRESUMO
OBJECTIVE: To describe a form of inflammatory myopathy with prominent involvement of the paraspinal and scapular muscles in patients with scleroderma. METHODS: Review of clinical records, laboratory investigations, and muscle biopsies. RESULTS: Patients presented with a "dropped head" resulting from weakness of the posterior cervical muscles (three cases) or camptocormia ("bent spine") resulting from weakness of the paraspinal muscles (two cases) and variable weakness and atrophy of shoulder girdle muscles with mild or absent pelvic girdle involvement. Biopsies from the deltoid or paraspinal muscles showed myositis of variable severity and scleroderma vasculopathy in all cases. The response to prednisolone and cytotoxic agents was poor, but there was a good response to intravenous immunoglobulin therapy in one case. CONCLUSIONS: Patients with scleroderma may develop a restricted form of immune-mediated inflammatory myopathy with a predilection for the paraspinal and scapular muscles, which is poorly responsive to treatment with glucocorticoids and immunosuppressive agents and may require consideration of other treatment modalities.
Assuntos
Doenças Musculares/complicações , Doenças Musculares/patologia , Escápula/patologia , Esclerodermia Localizada/complicações , Curvaturas da Coluna Vertebral/patologia , Adulto , Anticorpos Antinucleares/metabolismo , Antígenos CD/metabolismo , Eletromiografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Doenças Musculares/imunologia , Fator Reumatoide/imunologia , Esclerodermia Localizada/imunologiaRESUMO
OBJECTIVES: The study aimed to investigate the effects of a combined functional and aerobic exercise program on aerobic capacity, muscle strength, and functional mobility in a group of patients with sporadic inclusion body myositis (IBM). METHODS: Aerobic capacity, muscle strength, and functional capacity assessments were conducted on 7 participants with sporadic IBM before and after a 12-week exercise program, which included resistance exercises and aerobic stationary cycling 3 times per week on alternative days. RESULTS: Aerobic capacity of the group increased significantly by 38%, and significant strength improvements were observed in 4 of the muscle groups tested (P < 0.05). The exercise program was well tolerated, and there was no significant change in the serum creatine kinase level after the exercise period. CONCLUSIONS: An aerobic exercise program can be safely tolerated by patients with sporadic IBM and can improve aerobic capacity and muscle strength when combined with resistance training. These findings indicate that aerobic and functional muscle strengthening exercise should be considered in the management of patients with IBM.
Assuntos
Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Miosite de Corpos de Inclusão/fisiopatologia , Miosite de Corpos de Inclusão/reabilitação , Consumo de Oxigênio/fisiologia , Idoso , Ciclismo , Creatina/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Força Muscular/fisiologia , Equilíbrio Postural , Resultado do TratamentoRESUMO
Our purpose was to measure the change in quality of life (QoL) following deep brain stimulation of the globus pallidus interna (GPi-DBS) in advanced Parkinson 's disease (PD), and identifies any associations with changes in motor features of the disease. Eleven patients (age range 54-69 years, 2 women) underwent GPi-DBS (4 unilateral, 7 bilateral). Outcome measures included assessment of PD-specific QoL (mean 8 months postsurgery) using the PDQ-39 questionnaire, and standard motor assessments. Off-period UPDRS III motor scores fell by (43 +/- 8)% (mean +/- SEM). Dyskinesia severity was reduced on the abnormal involuntary movement scale by (80 +/- 3)% and UPDRS IVa by (58 +/- 8)%. QoL as assessed by the PDQ39SI improved by (30 +/- 5)%, with significant improvements in mobility, activities of daily living, bodily discomfort, emotional wellbeing, communication, and cognitions subscales. Bilateral and unilateral groups demonstrated equivalent PDQ39SI improvement. QoL improvement was highly correlated with dyskinesia reduction but not reduction in UPDRS score or age at surgery. GPi-DBS markedly improves QoL in advanced PD. The impacts are broad and improve QoL domains not directly affected by the motor symptoms of the disease. Reduced dyskinesia plays a major role in the improvement of QoL in GPi-DBS treated patients.
Assuntos
Estimulação Encefálica Profunda , Globo Pálido/fisiopatologia , Limitação da Mobilidade , Doença de Parkinson/terapia , Qualidade de Vida/psicologia , Atividades Cotidianas/psicologia , Sintomas Afetivos/fisiopatologia , Sintomas Afetivos/psicologia , Sintomas Afetivos/terapia , Idoso , Dominância Cerebral/fisiologia , Discinesias/fisiopatologia , Discinesias/psicologia , Discinesias/terapia , Feminino , Humanos , Hipocinesia/fisiopatologia , Hipocinesia/psicologia , Hipocinesia/terapia , Masculino , Pessoa de Meia-Idade , Rigidez Muscular/fisiopatologia , Rigidez Muscular/psicologia , Rigidez Muscular/terapia , Exame Neurológico , Neuronavegação , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Papel do DoenteRESUMO
Primary orthostatic tremor (OT) is a rare but disabling condition characterized by leg tremor and feelings of instability during stance. Previous studies have reported a reduction in OT symptoms with gabapentin treatment. In this study, we report on the benefits of gabapentin treatment in a double-blind placebo-controlled crossover study of 6 OT patients. First, the maximally effective gabapentin dosage (600-2,700 mg/day) for each patient was determined during an initial dose-titration phase. Patients were then studied 7 days after drug withdrawal and again after two 2-week periods of treatment with either gabapentin or placebo, using force platform posturography to quantify postural sway and tremor. Other medications for OT were continued unchanged. Symptomatic response was assessed by a patient-rated severity scale and quality of life (QOL) questionnaire. All patients reported an increase in symptoms during the washout phase and symptom reduction (50%-75%) during gabapentin treatment. Tremor amplitude was reduced to 79% +/- 11% and sway area to 71% +/- 11% of the placebo state. QOL improved in all patients, no adverse drug effects were noted, and symptomatic benefit was maintained at follow-up (mean = 19 months). The findings confirm that gabapentin is an effective treatment for OT, reducing both tremor and postural instability and improving quality of life, and support its use as add-on or first-line therapy for OT.
Assuntos
Aminas/uso terapêutico , Antiparkinsonianos/uso terapêutico , Ácidos Cicloexanocarboxílicos/uso terapêutico , Tontura/tratamento farmacológico , Equilíbrio Postural/efeitos dos fármacos , Tremor/tratamento farmacológico , Ácido gama-Aminobutírico/uso terapêutico , Idoso , Aminas/efeitos adversos , Antiparkinsonianos/efeitos adversos , Estudos Cross-Over , Ácidos Cicloexanocarboxílicos/efeitos adversos , Tontura/diagnóstico , Método Duplo-Cego , Feminino , Seguimentos , Gabapentina , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Qualidade de Vida , Recidiva , Síndrome de Abstinência a Substâncias/diagnóstico , Tremor/diagnóstico , Ácido gama-Aminobutírico/efeitos adversosRESUMO
Primary orthostatic tremor (OT) is characterized by leg tremor and instability on standing. High frequency (13-18 Hz) tremor bursting is present in leg muscles during stance, and posturography has shown greater than normal sway. We report on an open-label add-on study of gabapentin in 6 patients with OT. Six patients were studied with surface electromyography, force platform posturography, and a modified Parkinson's disease questionnaire (PDQ-39) quality of life (QOL) scale before and during treatment with gabapentin 300 mg t.d.s. If on other medications for OT, these were continued unchanged. Of the 6 patients, 4 reported a subjective benefit of 50 to 75% with gabapentin, 3 of whom showed reduced tremor amplitude and postural sway of up to 70%. Dynamic balance improved in all 3 patients who completed the protocol. QOL data from 5 patients showed improvement in all cases. No adverse effects were noted. Gabapentin may improve tremor, stability, and QOL in patients with OT, and symptomatic response correlated with a reduction in tremor amplitude and postural sway. The findings confirm previous reports of symptomatic benefit with gabapentin and provide justification for larger controlled clinical trials. Further work is required to establish the optimal dosage and to validate the methods used to quantify the response to treatment.