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《Brain stimulation》2022,15(2):337-351
BackgroundAbnormalities in frontoparietal network (FPN) were observed in many neuropsychiatric diseases including substance use disorders. A growing number of studies are using dual-site-tACS with frontoparietal synchronization to engage this network. However, a computational pathway to inform and optimize parameter space for frontoparietal synchronization is still lacking. In this case study, in a group of participants with methamphetamine use disorders, we proposed a computational pathway to extract optimal electrode montage while accounting for stimulation intensity using structural and functional MRI.MethodsSixty methamphetamine users completed an fMRI drug cue-reactivity task. Four main steps were taken to define electrode montage and adjust stimulation intensity using 4x1 high-definition (HD) electrodes for a dual-site-tACS; (1) Frontal seed was defined based on the maximum electric fields (EF) predicted by simulation of HD montage over DLPFC (F3/F4 in EEG 10–10), (2) frontal seed-to-whole brain context-dependent correlation was calculated to determine connected regions to frontal seeds, (3) center of connected cluster in parietal cortex was selected as a location for placing the second set of HD electrodes to shape the informed montage, (4) individualized head models were used to determine optimal stimulation intensity considering underlying brain structure. The informed montage was compared to montages with large electrodes and classic frontoparietal HD montages (F3-P3/F4-P4) in terms of tACS-induced EF and ROI-to-ROI task-based/resting-state connectivity.ResultsCompared to the large electrodes, HD frontoparietal montages allow for a finer control of the spatial peak fields in the main nodes of the FPN at the cost of lower maximum EF (large-pad/HD: max EF[V/m] = 0.37/0.11, number of cortical sub-regions that EF exceeds 50% of the max = 77/13). For defining stimulation targets based on EF patterns, using group-level head models compared to a single standard head model results in comparable but significantly different seed locations (6.43 mm Euclidean distance between the locations of the frontal maximum EF in standard-space). As expected, significant task-based/resting-state connections were only found between frontal-parietal locations in the informed montage. Cue-induced craving score was correlated with frontoparietal connectivity only in the informed montage (r = ?0.24). Stimulation intensity in the informed montage, and not in the classic HD montage, needs 40% reduction in the parietal site to reduce the disparity in EF between stimulation sites.ConclusionThis study provides some empirical insights to montage and dose selection in dual-site-tACS using individual brain structures and functions and proposes a computational pathway to use head models and functional MRI to define (1) optimum electrode montage for targeting FPN in a context of interest (drug-cue-reactivity) and (2) proper transcranial stimulation intensity. 相似文献
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Cost‐Effectiveness and Cost‐Utility Analysis of Spinal Cord Stimulation in Patients With Failed Back Surgery Syndrome: Results From the PRECISE Study
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Furio Zucco MD Roberta Ciampichini MSc Angelo Lavano MD Amedeo Costantini MD Marisa De Rose MD Paolo Poli MD Gianpaolo Fortini MD Laura Demartini MD Enrico De Simone MD Valentino Menardo MD Piero Cisotto MD Mario Meglio MD Luciana Scalone PhD Lorenzo G. Mantovani DSc 《Neuromodulation》2015,18(4):266-276
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董妍妍 《江西中医药大学学报》2020,32(3):118-120
糖尿病渐以年轻化的趋势呈现,糖尿病周围神经病变(DPN)是糖尿病最常见的慢性并发症之一,因其高致残率严重影响病患的生活品质。本文简单阐述糖尿病周围神经病变的病因,并就中医药的角度对该病的治疗概况进行综述,以期为临床诊治提供新见解和新研究策略。 相似文献
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《Clinical genitourinary cancer》2021,19(6):e409-e416
BackgroundThe immune system plays an important role in the pathogenesis of Alzheimer disease (AD), but it remains unclear whether bacillus Calmette-Guérin (BCG) may affect the risk of AD or not.MethodsUsing retrospective chart review, we collected data regarding demographics, comorbidities, cancer diagnosis, BCG treatment, and subsequent diagnosis of AD or other dementia in a racially/ethnically diverse cohort of patients with non–muscle-invasive bladder cancer (NIMBC) receiving treatment between 1984 and 2020 in the Bronx, New York. We used Cox proportional hazard models to examine association between BCG treatment and risk of incident AD or other dementia, adjusting for age, gender, race/ethnicity, and major comorbidities.ResultsIn our cohort of 1290 patients with NMIBC, a total of 99 (7.7%) patients developed AD or other dementia during follow-up. Patients who received BCG treatment (25%) had a 60% lowered incidence of AD or other dementia (adjusted hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.21-0.80) in comparison to those who did not receive BCG. There was also suggestive evidence that the reduction in risk of AD or other dementia associated with BCG treatment was stronger in men (adjusted HR, 0.34; 95% CI, 0.15-0.81) but not in women (adjusted HR, 0.75; 95% CI 0.25-2.24). When we stratified the patients who received BCG by type of treatments, patients who received both induction and maintenance rounds of BCG had a further lowered incidence of AD or other dementia (HR, 0.23; 95% CI, 0.06-0.96) than patients who did not receive BCG.ConclusionsTo our knowledge, our study is one of the first to suggest that BCG treatment is associated with a reduced risk of developing AD or other dementia in a multiethnic population, independent of significant comorbidities. Larger cohort studies are needed to corroborate our findings. 相似文献
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Shingo Hashimoto Masaki Katsurada Rie Muramatsu Kumiko Asai Kenichiro Tanaka Kensuke Hayashi Yoshiaki Kibe Koichiro Nakajima Yukiko Hattori Hiromitsu Iwata Jun-etsu Mizoe Hiroyuki Ogino Yuta Shibamoto 《Practical radiation oncology》2019,9(2):e149-e155
Purpose
Suppression of respiratory movement of the liver would be desirable for high-precision radiation therapy for liver tumors. We aimed to investigate the effect of our original device-free compressed shell fixation method and breathing instruction on suppression of respiratory movement. The characteristics of liver motion based on the movement of a fiducial marker were also analyzed.Methods and Materials
First, respiratory amplitudes of the liver with the device-free compressed shell were analyzed from the data of 146 patients. The effect of this shell fixing method on liver movement was evaluated. Second, as another cohort study with 166 patients, interfractional internal motion of the liver for patients fixed in the shell was calculated using the fiducial marker coordinate data of images for position setting before daily irradiation. Third, in another 12 patients, intrafractional internal motion was calculated from the fiducial marker coordinate data using x-ray images before and after irradiation.Results
The median respiratory movement without the shell, after fixing with the shell, and after instructing on the breathing method with the shell was 14.2 (interquartile range, 10.7-19.8), 11.5 (8.6-17.5), and 10.4 mm (7.3-15.8), respectively. Systematic and random errors of interfractional internal motion were all ≤2 mm in the left-right and anteroposterior directions and 3.7 and 3.0 mm, respectively, in the craniocaudal direction. Systematic and random errors of intrafractional internal motion were all ≤1.3 mm in the left-right and anteroposterior directions and 0.8 and 2.4 mm, respectively, in the craniocaudal direction.Conclusions
The device-free compressed shell fixation method was effective in suppressing the respiratory movement of the liver. Irradiation position matching using the fiducial marker can correct the interfractional internal motion on each day, which would contribute to the reduction of the margin to be given around the target. 相似文献8.
An-feng TAO Zheng-hao XU Cheng-hao WU Yi WANG Wei-wei HOU Shi-hong ZHANG Zhong CHEN 《浙江大学学报(医学版)》2015,44(3):315
目的观察比较不同脉冲波形的低频率电刺激对海马电点燃癫痫模型小鼠的作用差异。方法采用电点燃刺激法建立小鼠癫痫模型, 观察正弦波、单相方波、双相方波低频率电刺激对模型小鼠癫痫行为发作及后放电持续时间的影响, 并比较不同时间点给予正弦波低频率电刺激的抗癫痫作用。结果与对照组比较, 正弦波低频率电刺激30 s能降低小鼠海马电点燃癫痫发作等级(2.85 ± 0.27 vs 4.75 ±0.12, P < 0.05)、减少大发作概率(53.6% vs 96.5%, P < 0.01) 和缩短后放电持续时间[(16.22 ± 1.69) s vs (30.29 ± 1.12) s, P < 0.01], 而单相方波和双相方波低频率电刺激30 s没有明显的抗癫痫作用。常用的单相方波低频率电刺激15 min能降低小鼠海马电点燃发作等级(3.58 ± 0.16, P < 0.05)、减少大发作概率(66.7%, P < 0.01);但对海马后放电持续时间及大发作持续时间无影响(均 P>0.05)。此外, 电点燃刺激前预先给予或结束后3 s内给予正弦波低频率电刺激具有明显的抗癫痫作用( P < 0.05或 P < 0.01), 而电点燃刺激结束10 s给予正弦波低频率电刺激则无上述抗癫痫作用。 结论低频率电刺激抗癫痫作用受波形参数的影响, 其中正弦波低频率电刺激能有效抑制小鼠海马电点燃癫痫的发作。 相似文献
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高强度聚焦超声(high-intensity focused ultrasound,HIFU)消融治疗子宫肌瘤作为一种新的非侵入性的治疗方式,已越来越广泛地用于子宫肌瘤的治疗。但是对于HIFU治疗时妊娠的处理及妊娠结局鲜有文献报道。本文报道1例HIFU消融治疗子宫肌瘤时妊娠的病例,结合文献复习,探讨子宫平滑肌瘤对妊娠的影响、子宫平滑肌瘤不同处理方式对妊娠的影响、HIFU消融治疗子宫肌瘤时机选择的问题、HIFU消融治疗子宫肌瘤若同时合并妊娠时胎儿去留的问题以及近期HIFU消融治疗子宫肌瘤后对流产手术操作的影响等,以期对HIFU治疗子宫肌瘤的适应证、选择合适的治疗时间及术后选择合适的妊娠时机展开讨论。 相似文献
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