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61.
《Clinical neurophysiology》2021,132(8):1845-1849
ObjectivePatients with myasthenia gravis associated with muscle-specific tyrosine kinase antibodies (MuSK-MG) often manifest signs of cholinergic hyperactivity with standard doses of acetylcholinesterase inhibitors (AChE-Is). Aim of the study was to investigate whether repetitive compound muscle action potential (R-CMAP), the neurophysiological correlate of cholinergic hyperactivity, was present in MuSK-MG irrespective of AChE-I treatment.MethodsPatients with confirmed diagnosis of MuSK-MG were consecutively enrolled during follow-up visits, from January 2019 to April 2020. All these subjects underwent the same neurophysiological protocol, including motor nerve conduction studies and repetitive nerve stimulation. In patients taking pyridostigmine, neurophysiological testing was performed at least 12 hours after the last dose. For comparison, the presence of R-CMAP was investigated in 20 consecutive acetylcholine receptor antibody positive myasthenia gravis (AChR-MG) patients.ResultsWe enrolled 25 MuSK-MG patients (20 females), aged 16–79 years at the study time, with disease duration ranging 0.6–48.8 years (median: 17.7 years). R-CMAP was detected in 12/25 (48%) MuSK-MG cases and in none of the AChR-MG controls (p = 0.0003). In the MuSK-MG population, a history of muscle cramps and fasciculations, during low-dose pyridostigmine therapy, was significantly more frequent in R-CMAP positive than in R-CMAP negative patients (100% vs 31%, p = 0.001). At the time of the study, the proportion of patients still symptomatic for MG was higher among R-CMAP positive cases (92% vs 23%, p = 0.0005).ConclusionsCholinergic hyperactivity is a relatively common finding in MuSK-MG patients, independent of AChE-I treatment, and may constitute an intrinsic feature of the disease.SignificanceR-CMAP detection can represent a useful diagnostic clue for MuSK-MG and predicts poor tolerance to AChE-Is. 相似文献
62.
《Brain stimulation》2021,14(4):927-937
BackgroundIncreases in the volume of the amygdala and hippocampus after electroconvulsive therapy (ECT) are among the most robust effects known to the brain-imaging field. Recent advances in the segmentation of substructures of these regions allow for novel insights on the relationship between brain structure and clinical outcomes of ECT.ObjectiveWe aimed to provide a comprehensive synthesis of evidence available on changes in brain structure after ECT, including recently published data on hippocampal subfields.MethodsA meta-analysis of published studies was carried out using random-effects models of standardized mean change of regional brain volumes measured with longitudinal magnetic resonance imaging of depressive patients before and after a series of ECT.ResultsData from 21 studies (543 depressed patients) were analysed, including 6 studies (118 patients) on hippocampal subfields. Meta-analyses could be carried out for seven brain regions for which data from at least three published studies was available. We observed increases in left and right hippocampi, amygdalae, cornua ammonis (CA) 1, CA 2/3, dentate gyri (DG) and subicula with standardized mean change scores ranging between 0.34 and 1.15. The model did not reveal significant volume increases in the caudate. Meta-regression indicated a negative relationship between the reported increases in the DG and relative symptom improvement (−0.27 (SE: 0.09) per 10%).ConclusionsECT is accompanied by significant volume increases in the bilateral hippocampus and amygdala that are not associated with treatment outcome. Among hippocampal subfields, the most robust volume increases after ECT were measured in the dentate gyrus. The indicated negative correlation of this effect with antidepressant efficacy warrants replication in data of individual patients. 相似文献
63.
《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials. 相似文献
64.
ObjectiveThis study aimed to evaluate ocular vascularity in young adult migraine patients with visual aura and without visual aura.Material and MethodsThe study included 30 patients with migraine with visual aura (MWVA), 30 patients with migraine without visual aura (MWOVA), and 30 healthy control subjects, all between ages ≥18 and <45. Migraine patients were applied Headache Impact Test (HIT) and Migraine Disability Assessment Scale (MIDAS). Retinal nerve fiber layer thickness and ocular vascularity of all participants were evaluated with optical coherence tomography (OCT) and OCT angiography (OCTA).ResultsThe MWVA group had significantly lower superficial and deep foveal vascular density values compared to the control group (p = 0.039, p = 0.028, respectively). The foveal avascular zone was significantly enlarged in the MWVA group compared to the control group (p = 0.033). MWVA patients had significantly lower whole optic disc, optic disc inside, peripapillary, superior hemisphere, inferior hemisphere, superior quadrant, and temporal quadrant vascular density values compared to the control group (p < 0.05 all), while there was no significant difference in the nasal quadrant (p = 0.083). Migraine attack frequency, MIDAS, and HIT were negatively correlated with ocular vascular density values.ConclusionThe results of our study indicate that young adult patients with MWVA are at risk of decreased ocular vascularity and that this risk may increase with frequency and severity of migraine attacks. 相似文献
65.
目前在中医界已发布的冠心病痰湿证辨证标准是以主症、次症形式定性地给出,存在主观性较强的问题。本文引入约束隐结构分析,该方法将主症、次症的语义作为约束条件加入隐结构分析过程,得到含有主症、次症语义约束的定量化中医证候辨证规则。使用该方法对冠心病痰湿证患者556条无标签数据的分析,得到其约束隐结构模型,最后建立定量化痰湿证辨证规则,舌胖边有齿痕(3.16)、苔腻(3.12)、苔白滑(4.72)、胸闷(1.73)、脉濡或滑(6.04);次症:肢体困重(0.48)、口黏(0.63)、体胖(0.49)、大便粘滞(1.38)、脘腹痞满(0.97)、面色晦浊(0.79)、嗜睡(1.18)、纳差(1.07)。与经典隐结构模型得到规则和中医界已发布的定性化辨证规则相比,约束隐结构得到的规则客观性强,具有可重复性。在证候类大小、规则的量化合理度上较好地反映了主症、次症的特点,得到的规则切合中医实际,为冠心病痰湿证辨证标准的定量化研究提供帮助和参考。 相似文献
66.
膝骨关节炎(KOA)属于进展性骨关节病,其功能障碍主要表现为膝关节疼痛、僵硬、屈伸行走不利或受限,以及关节失稳、运动控制下降和本体感觉低下等。我国KOA患者众多,且还在逐年增加,引起的功能障碍严重影响着患者健康与生活质量,因此对其开展康复的研究与实践至关重要。中医康复着眼于功能,注重辨证康复,是我国康复医学的固有特色及优势。前期的研究基于KOA功能障碍的中医证候表现,本研究经大量文献梳理及多年临床实践,从“筋骨、痹痿、虚实、动静、刚柔”5个角度为切入点,提出KOA功能障碍具有“筋骨同病、痹痿并见、虚实错杂、动静失衡、刚柔失常”5个基本特点。鉴于KOA功能障碍具有早、中、晚三期的阶段性特点,在该病发生发展的不同阶段,其功能障碍在“筋骨、痹痿、虚实、动静、刚柔”之间的表现又各有所侧重。本研究从“筋骨同病、痹痿并见、虚实错杂、动静失衡、刚柔失常”5个方面分别阐释了KOA功能障碍的特点:“筋骨同病”侧重于病位,是KOA所致功能障碍的基本病机特征,贯穿于其发病的始终;“痹痿并见、虚实错杂”偏重病性,是KOA功能障碍的基本特点;“动静失衡”偏重病因,是引起KOA病情反复及加重的重要因素;“刚柔失常”则是兼具病状与病因,是膝关节失去“骨正筋柔”的表现方式,也是KOA功能障碍的重要特征。本研究旨在进一步完善KOA的中医康复理论,为其康复治疗提供参考。 相似文献
67.
目的探讨《临证指南医案》痹证用药特点。方法 运用数据挖掘技术统计药物使用频次、性味归经并进行关联规则、聚类、复杂网络分析等。结果 筛选出83首处方,共涉及中药125味,使用频次前5位依次为桂枝、茯苓、白术、当归、苦杏仁,功效类别以补虚药为主,性味以甘温最多,归经主要涉及肺、脾、肝、心、肾、胃;关联规则得到10对常见组合,高频中药聚为4类,复杂网络分析得到1个核心组合。结论 叶氏常从络病角度治痹,或通、或补、或通补皆施,重视肺脾,注重调和气血营卫,擅长通补奇经治法。 相似文献
68.
Neal A. Carnes James W. Carey Deborah J. Gelaude Damian J. Denson Patricia A. Bessler 《AIDS care》2021,33(1):63-69
ABSTRACT Expeditious linkage and consistent engagement in medical care is important for people with HIV’s (PWH) health. One theory on fostering linkage and engagement involves HIV status disclosure to mobilize social support. To assess disclosure and social support’s association with linkage and engagement, we conducted a qualitative study sampling black and Latino men who have sex with men (MSM of color) in the U.S. Participants' narratives presented mixed results. For instance, several participants who reported delaying, inconsistent access, or detachment from care also reported disclosing for support purposes, yet sporadic engagement suggests that their disclosure or any subsequent social support have not assisted. The findings contribute to the literature that questions disclosure and social support’s influence on care engagement, especially when decontextualized from circumstances and intentions. Our findings suggest the mechanics of disclosure and social support require planned implementation if intending to affect outcomes, especially among MSM of color. From the findings, we explore steps that may bolster interventions seeking to anchor medical care engagement. 相似文献
69.
Bong Gun Lee Jung-Hwan Choi Dong-Yun Kim Won Rak Choi Seung Gun Lee Chang-Nam Kang 《The spine journal》2019,19(2):301-305
Background context
It has been reported that newly developed osteoporotic vertebral compression fractures (OVCFs) occur at a relatively high frequency after treatment. While there are many reports on possible risk factors, these have not yet been clearly established.Purpose
The purpose of this study was to investigate the risk factors for newly developed OVCFs after treatment by vertebroplasty (VP), kyphoplasty (KP), or conservative treatment.Study design/setting
A retrospective comparative study.Patient sample
One hundred thirty-two patients who had radiographic follow-up data for one year or longer among 356 patients who were diagnosed with OVCF and underwent VP, KP or conservative treatment between March 2007 and February 2016.Outcome measures
All records were examined for age, sex, body mass index (BMI), rheumatoid arthritis and other medical comorbidities, osteoporosis medication, bone mineral density (BMD), history of vertebral and nonvertebral fractures, treatment methods used, level of fractures, and presence of multiple fracture sites.Methods
Patients were divided into those who manifested new OVCF (Group A) and those who did not (Group B). For the risk factor analysis, student's t-tests and chi-square tests were used in univariate analysis. Multivariate logistic regression analysis was carried out on variables with a p<.1 in the univariate analysis.Results
Newly developed OVCFs occurred in 46 of the 132 patients (34.8%). Newly developed OVCF increased significantly with factors such as average age (p=.047), low BMD T-score of the lumbar spine (p=.04) and of the femoral neck (p=.046), advanced age (>70 years) (p=.011), treatment by cement augmentation (p=.047) and low compliance with osteoporosis medication (p=.029). In multivariate regression analysis, BMD T-score of the lumbar spine (p=.009) and treatment by cement augmentation (p=.044) showed significant correlations with the occurrence of new OVCFs with a predictability of 71.4%.Conclusion
Osteoporotic vertebral compression fracture patients with low BMD T-score of the lumbar spine and those who have been treated by cement augmentation have an increased risk of new OVCFs after treatment and, therefore, require especially careful observation and attention. 相似文献70.
Osric A. Forrest Daniel M. Chopyk Yael Gernez Milton R. Brown Carol K. Conrad Richard B. Moss Vin Tangpricha Limin Peng Rabindra Tirouvanziam 《Journal of cystic fibrosis》2019,18(1):64-70