The dying-back hypothesis holds that the damage to neuromuscular junctions and distal axons in amyotrophic lateral sclerosis occurs at the earliest stage of the disease.Previous basic studies have confirmed early dama...The dying-back hypothesis holds that the damage to neuromuscular junctions and distal axons in amyotrophic lateral sclerosis occurs at the earliest stage of the disease.Previous basic studies have confirmed early damage to neuromuscular junctions,but it is difficult to obtain such evidence directly in clinical practice.In this prospective cross-sectional study,we recruited 22 patients with early amyotrophic lateral sclerosis with disease duration < 12 months and with clinical symptoms limited to the upper limbs.We also recruited 32 healthy controls.Repetitive nerve stimulation was performed,and patients were followed for 12 months.We found a significant change in the response to repetitive nerve stimulation in amyotrophic lateral sclerosis patients without spontaneous electromyographic activity.Patients that were prone to denervation had an increased decrement response of target muscles after repetitive nerve stimulation.These results suggest that changes in response to repetitive nerve stimulation may occur before denervation in amyotrophic lateral sclerosis patients.The damage to lower motor neurons is more obvious in patients with a higher percentage of repetitive never stimulation-related amplitude decrements.This study was approved by the Institutional Ethics Committee of Peking University Third Hospital(approval No.M2017198) on August 24,2017.展开更多
Background： Nowadays, it is widely known that decremental responses in low-frequency repetitive nerve stimulation （LF-RNS） are frequently observed in patients with amyotrophic lateral sclerosis （ALS）. The patholo...Background： Nowadays, it is widely known that decremental responses in low-frequency repetitive nerve stimulation （LF-RNS） are frequently observed in patients with amyotrophic lateral sclerosis （ALS）. The pathological mechanism of this phenomenon remains unknown. This study aimed to illuminate the features of RNS in Chinese patients with ALS. Methods： Clinical and electrophysiological data of 146 probable and definite ALS patients who underwent RNS were retrospectively enrolled and analyzed. LF-RNS （3 Hz） was performed in trapezius, deltoid, abductor digiti minimi （ADM）, quadriceps femoris, and tibialis anterior. High-frequency RNS （HF-RNS, 10 Hz） was performed only in ADM. The two-sample t-test and Chi-squared test were used for statistical analysis.Results： Decremental responses to LF-RNS （≥ 10%） in at least one muscle were detected in 83 （56.8%） of the cases and were most commonly seen in trapezius and deltoid. The incidence ofdecremental response was higher in patients with upper limb onset. Incremental responses to HF-RNS （≥60%） in ADM were observed in 6 （5.6%） of the cases. In 106 muscles with decremental response, 62 （57.4%） muscles had a continuous decremental pattern, more than a U-shape pattern （37 cases, 34.3%）. Nineteen cases showed definite decrements in LF-RNS tests in trapezius, while no abnormalities were found in the electromyography and neurological examination of the sternocleidomastoid muscle, supplied by the accessory nerve as well.Conclusions： Decremental responses in the RNS are commonly observed in ALS patients. The findings regarding the trapezius indicated that some ALS onsets could be initiated by a ＂dying back＂ process, with destruction of neuromuscular junctions （NMJs） before motor neurons. Incremental responses in the ADM implied damage of the NMJs involved both the post and presynaptic membranes.展开更多
Low-frequency repetitive transcranial magnetic stimulation（LF-r TMS） to the contralesional hemisphere and intensive occupational therapy（i OT） have been shown to contribute to a significant improvement in upper li...Low-frequency repetitive transcranial magnetic stimulation（LF-r TMS） to the contralesional hemisphere and intensive occupational therapy（i OT） have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-r TMS and i OT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient＇s Trail-Making Test part B（TMT-B） performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-r TMS to the contralesional hemisphere and 2 sessions of i OT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-r TMS to the contralesional hemisphere combined with i OT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function.展开更多
Background The aim of this study was to evaluate single fiber electromyography (SFEMG) in the diagnosis of ocular myasthenia gravis (OMG),compared with repetitive nerve stimulation (RNS) and blood concentration of ant...Background The aim of this study was to evaluate single fiber electromyography (SFEMG) in the diagnosis of ocular myasthenia gravis (OMG),compared with repetitive nerve stimulation (RNS) and blood concentration of antibody to acetylcholine receptor (AchRAb).Methods SFEMG,RNS and AchRAb titration were measured in 90 patients with OMG (44 men,46 women). Results Markedly increased jitter and ratio of block in the frontalis and the extensor digitorum communis (EDC) were observed (83.3% and 61.1%,respectively). The mean jitter was 43.6±14.5 μs,and the percentages of jitter>55 μs and blocking were 16.9%±19% and 3.5%±9.5% respectively in the EDC. The mean jitter was 64.3±25.6 μs,and the percentages of jitter >55 μs and blocking were 33.5%±27.6% and 29.3%±23.2% respectively in the frontalis. The percentage of abnormal RNS was 27.8% (25/90). There was an increased AchRAb titration in 29 (32.2%) of the 90 patients. Increased jitter,blocking was negatively correlated with maximum decrement to RNS ( P <0.01). 11.4% (4/35) of patients with abnormal RNS and 24.1% (7/29) patients with abnormal AchRAb were seen in the patients with normal SFEMG in the EDC. Conclusion SFEMG test showed the highest sensitivity in the diagnosis of OMG. To our knowledge, the three methods (SFEMG,RNS and AchRAb) are complementary in the diagnosis and differential diagnosis of OMG.展开更多
文摘The dying-back hypothesis holds that the damage to neuromuscular junctions and distal axons in amyotrophic lateral sclerosis occurs at the earliest stage of the disease.Previous basic studies have confirmed early damage to neuromuscular junctions,but it is difficult to obtain such evidence directly in clinical practice.In this prospective cross-sectional study,we recruited 22 patients with early amyotrophic lateral sclerosis with disease duration < 12 months and with clinical symptoms limited to the upper limbs.We also recruited 32 healthy controls.Repetitive nerve stimulation was performed,and patients were followed for 12 months.We found a significant change in the response to repetitive nerve stimulation in amyotrophic lateral sclerosis patients without spontaneous electromyographic activity.Patients that were prone to denervation had an increased decrement response of target muscles after repetitive nerve stimulation.These results suggest that changes in response to repetitive nerve stimulation may occur before denervation in amyotrophic lateral sclerosis patients.The damage to lower motor neurons is more obvious in patients with a higher percentage of repetitive never stimulation-related amplitude decrements.This study was approved by the Institutional Ethics Committee of Peking University Third Hospital(approval No.M2017198) on August 24,2017.
基金This study was supported by grants from the National Natural Science Foundation of China （No. 81671278 and No. 81601096）, One Hundred Advantage Projects ＂Fund of Chinese PLA General Hospital＂ （No. YS201415）, and Key Research and Development Plan of Hainan Province （No. ZDFY2016120）.
文摘Background： Nowadays, it is widely known that decremental responses in low-frequency repetitive nerve stimulation （LF-RNS） are frequently observed in patients with amyotrophic lateral sclerosis （ALS）. The pathological mechanism of this phenomenon remains unknown. This study aimed to illuminate the features of RNS in Chinese patients with ALS. Methods： Clinical and electrophysiological data of 146 probable and definite ALS patients who underwent RNS were retrospectively enrolled and analyzed. LF-RNS （3 Hz） was performed in trapezius, deltoid, abductor digiti minimi （ADM）, quadriceps femoris, and tibialis anterior. High-frequency RNS （HF-RNS, 10 Hz） was performed only in ADM. The two-sample t-test and Chi-squared test were used for statistical analysis.Results： Decremental responses to LF-RNS （≥ 10%） in at least one muscle were detected in 83 （56.8%） of the cases and were most commonly seen in trapezius and deltoid. The incidence ofdecremental response was higher in patients with upper limb onset. Incremental responses to HF-RNS （≥60%） in ADM were observed in 6 （5.6%） of the cases. In 106 muscles with decremental response, 62 （57.4%） muscles had a continuous decremental pattern, more than a U-shape pattern （37 cases, 34.3%）. Nineteen cases showed definite decrements in LF-RNS tests in trapezius, while no abnormalities were found in the electromyography and neurological examination of the sternocleidomastoid muscle, supplied by the accessory nerve as well.Conclusions： Decremental responses in the RNS are commonly observed in ALS patients. The findings regarding the trapezius indicated that some ALS onsets could be initiated by a ＂dying back＂ process, with destruction of neuromuscular junctions （NMJs） before motor neurons. Incremental responses in the ADM implied damage of the NMJs involved both the post and presynaptic membranes.
文摘Low-frequency repetitive transcranial magnetic stimulation（LF-r TMS） to the contralesional hemisphere and intensive occupational therapy（i OT） have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-r TMS and i OT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient＇s Trail-Making Test part B（TMT-B） performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-r TMS to the contralesional hemisphere and 2 sessions of i OT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-r TMS to the contralesional hemisphere combined with i OT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function.
文摘Background The aim of this study was to evaluate single fiber electromyography (SFEMG) in the diagnosis of ocular myasthenia gravis (OMG),compared with repetitive nerve stimulation (RNS) and blood concentration of antibody to acetylcholine receptor (AchRAb).Methods SFEMG,RNS and AchRAb titration were measured in 90 patients with OMG (44 men,46 women). Results Markedly increased jitter and ratio of block in the frontalis and the extensor digitorum communis (EDC) were observed (83.3% and 61.1%,respectively). The mean jitter was 43.6±14.5 μs,and the percentages of jitter>55 μs and blocking were 16.9%±19% and 3.5%±9.5% respectively in the EDC. The mean jitter was 64.3±25.6 μs,and the percentages of jitter >55 μs and blocking were 33.5%±27.6% and 29.3%±23.2% respectively in the frontalis. The percentage of abnormal RNS was 27.8% (25/90). There was an increased AchRAb titration in 29 (32.2%) of the 90 patients. Increased jitter,blocking was negatively correlated with maximum decrement to RNS ( P <0.01). 11.4% (4/35) of patients with abnormal RNS and 24.1% (7/29) patients with abnormal AchRAb were seen in the patients with normal SFEMG in the EDC. Conclusion SFEMG test showed the highest sensitivity in the diagnosis of OMG. To our knowledge, the three methods (SFEMG,RNS and AchRAb) are complementary in the diagnosis and differential diagnosis of OMG.
