Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake...Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n = 10) at different time, while control group (n = 10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed. Results After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly(P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05). Conclusion rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.展开更多
The electrical excitability of neural networks is influenced by different environmental factors. Effective and simple methods are required to objectively and quantitatively evaluate the influence of such factors, incl...The electrical excitability of neural networks is influenced by different environmental factors. Effective and simple methods are required to objectively and quantitatively evaluate the influence of such factors, including variations in temperature and pharmaceutical dosage. The aim of this paper was to introduce ‘the voltage threshold measurement method', which is a new method using microelectrode arrays that can quantitatively evaluate the influence of different factors on the electrical excitability of neural networks. We sought to verify the feasibility and efficacy of the method by studying the effects of acetylcholine, ethanol, and temperature on hippocampal neuronal networks and hippocampal brain slices. First, we determined the voltage of the stimulation pulse signal that elicited action potentials in the two types of neural networks under normal conditions. Second, we obtained the voltage thresholds for the two types of neural networks under different concentrations of acetylcholine, ethanol, and different temperatures. Finally, we obtained the relationship between voltage threshold and the three influential factors. Our results indicated that the normal voltage thresholds of the hippocampal neuronal network and hippocampal slice preparation were 56 and 31 m V, respectively. The voltage thresholds of the two types of neural networks were inversely proportional to acetylcholine concentration, and had an exponential dependency on ethanol concentration. The curves of the voltage threshold and the temperature of the medium for the two types of neural networks were U-shaped. The hippocampal neuronal network and hippocampal slice preparations lost their excitability when the temperature of the medium decreased below 34 and 33°C or increased above 42 and 43°C, respectively. These results demonstrate that the voltage threshold measurement method is effective and simple for examining the performance/excitability of neuronal networks.展开更多
Background: Atrial AutoCaptureTM (ACapTM) was a new technological development that confirmed atrial capture by analyzing evoked response (ER) with a new method - paced depolarization integral ER detection- and op...Background: Atrial AutoCaptureTM (ACapTM) was a new technological development that confirmed atrial capture by analyzing evoked response (ER) with a new method - paced depolarization integral ER detection- and optimized energy output to changes in the stimulation threshold. The purpose of this study was to evaluate the clinical performance ofACapTM function. Methods: This was a prospective, observational, nonrandomized two-center study. Between November 2008 and August 2014, 102 patients were enrolled from two different institutions. Data were collected by case report forms at enrollment, hospital discharge, and in-office follow-ups scheduled at 1, 2, 3, 6, and 12 months postimplantation. Results: Ambulatory ACapTM function started to become available for 20.6% of patients at 1 day, then progressed to 30.4% at 7 days, 38.6% at 1 month, 41.6% at 2 months, 47.5% at 3 months, 53.5% at 6 months, and 63.4% at 1 year. The cause of the unsuccessful attempts to perform ACapTM threshold was ER/polarization 〈2:1. Availability for SD, BND, and HOCM indications had shown better results than AVB indication. For SD indication cases, feasibility was significantly better for SD with paroxysmal atrial fibrillation (pAF) than SD without pAF (78.4% vs. 35.0% at 1 year, n = 71, P 〈 0.001). At each stage of the clinical follow-ups, there had been a strict correlation between ACapTM measurements and those conducted manually with P 〈 0.001 (n = 299). Conclusions: It has been concluded that ACapTM function was safe and effective to confirm atrial threshold and reduce energy output automatically. ACapTM function is unavailable for some patients at early stages of the implantation; however, availability has been progressively increasing during follow-up.展开更多
文摘Objective To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitabi- lity and neurofunction after cerebral ischemia-reperfusion injury. Methods After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n = 10) at different time, while control group (n = 10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed. Results After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly(P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05). Conclusion rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.
基金supported by the National Natural Sciences Foundation of China,No.61534003,61076118the Innovation Foundation for State Key Laboratory of the Ministry of Science and Technology,China,No.2016-2018a grant from the Open Projects of Key Laboratory of Child Development and Learning of the Ministry of Education of China,No.CDLS201205
文摘The electrical excitability of neural networks is influenced by different environmental factors. Effective and simple methods are required to objectively and quantitatively evaluate the influence of such factors, including variations in temperature and pharmaceutical dosage. The aim of this paper was to introduce ‘the voltage threshold measurement method', which is a new method using microelectrode arrays that can quantitatively evaluate the influence of different factors on the electrical excitability of neural networks. We sought to verify the feasibility and efficacy of the method by studying the effects of acetylcholine, ethanol, and temperature on hippocampal neuronal networks and hippocampal brain slices. First, we determined the voltage of the stimulation pulse signal that elicited action potentials in the two types of neural networks under normal conditions. Second, we obtained the voltage thresholds for the two types of neural networks under different concentrations of acetylcholine, ethanol, and different temperatures. Finally, we obtained the relationship between voltage threshold and the three influential factors. Our results indicated that the normal voltage thresholds of the hippocampal neuronal network and hippocampal slice preparation were 56 and 31 m V, respectively. The voltage thresholds of the two types of neural networks were inversely proportional to acetylcholine concentration, and had an exponential dependency on ethanol concentration. The curves of the voltage threshold and the temperature of the medium for the two types of neural networks were U-shaped. The hippocampal neuronal network and hippocampal slice preparations lost their excitability when the temperature of the medium decreased below 34 and 33°C or increased above 42 and 43°C, respectively. These results demonstrate that the voltage threshold measurement method is effective and simple for examining the performance/excitability of neuronal networks.
文摘Background: Atrial AutoCaptureTM (ACapTM) was a new technological development that confirmed atrial capture by analyzing evoked response (ER) with a new method - paced depolarization integral ER detection- and optimized energy output to changes in the stimulation threshold. The purpose of this study was to evaluate the clinical performance ofACapTM function. Methods: This was a prospective, observational, nonrandomized two-center study. Between November 2008 and August 2014, 102 patients were enrolled from two different institutions. Data were collected by case report forms at enrollment, hospital discharge, and in-office follow-ups scheduled at 1, 2, 3, 6, and 12 months postimplantation. Results: Ambulatory ACapTM function started to become available for 20.6% of patients at 1 day, then progressed to 30.4% at 7 days, 38.6% at 1 month, 41.6% at 2 months, 47.5% at 3 months, 53.5% at 6 months, and 63.4% at 1 year. The cause of the unsuccessful attempts to perform ACapTM threshold was ER/polarization 〈2:1. Availability for SD, BND, and HOCM indications had shown better results than AVB indication. For SD indication cases, feasibility was significantly better for SD with paroxysmal atrial fibrillation (pAF) than SD without pAF (78.4% vs. 35.0% at 1 year, n = 71, P 〈 0.001). At each stage of the clinical follow-ups, there had been a strict correlation between ACapTM measurements and those conducted manually with P 〈 0.001 (n = 299). Conclusions: It has been concluded that ACapTM function was safe and effective to confirm atrial threshold and reduce energy output automatically. ACapTM function is unavailable for some patients at early stages of the implantation; however, availability has been progressively increasing during follow-up.