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排序方式: 共有1326条查询结果,搜索用时 15 毫秒
1.
《Sleep medicine》2021
Study objectivesTo evaluate neurophysiological alterations of visual function in idiopathic REM sleep Behavior Disorder (iRBD) both as markers and predictors of neurodegenerative disorders.MethodsIn a longitudinal follow-up study of 46 consecutive iRBD patients (follow-up duration 8.4 ± 3.4 years), the baseline parameters in luminance-contrast pattern (VEPp), red-green color (VEPc) and motion-onset (VEPm) Visual Evoked Potentials in iRBD were compared to early (ePD) and advanced (aPD) Parkinson's Disease subjects. Parameters of latency and amplitude of iRBD converters to neurodegenerative disease were compared with those of the non-converters.ResultsThe VEP P100 mean latency values for both eyes and for both stimulation checks (30′ and 15’) were significantly longer in all the three groups of patients as compared to controls; moreover latencies were longer in aPD than in the iRBD group who did not differ from the ePD group. The same held true when we analyzed the number of abnormal subjects belonging to each diagnostic group with a higher number of abnormal subjects in the aPD group compared to both the ePD and in iRBD groups. Chromatic and motion potentials were not different from controls and did not differ in the 3 diagnostic groups. The iRBD subjects who converted to a neurodegenerative disorder showed longer P100 latencies and a higher occurrence of VEPp abnormalities than those who did not convert. Again chromatic and motion VEPs were not different depending on conversion.ConclusionsIn iRBD patients the detection of an abnormal VEPp should be considered as a red flag for possible synnucleinopathy, eventually contributing in stratifying the risk of phenoconversion. 相似文献
2.
IntroductionNoradrenergic denervation is thought to aggravate motor dysfunction in Parkinson's disease (PD). In a previous PET study with the norepinephrine transporter (NART) ligand 11C-MeNER, we detected reduced NART binding in primary sensorimotor cortex (M1S1) of PD patients. Idiopathic rapid-eye-movement sleep behaviour disorder (iRBD) is a phenotype of prodromal PD. Using 11C-MeNER PET, we investigated whether iRBD patients showed similar NART binding reductions in M1S1 cortex as PD patients. Additionally, we investigated whether 11C-MeNER binding and loss of nigrostriatal dopamine storage capacity measured with 18F-DOPA PET were correlated.Methods17 iRBD patients, 16 PD patients with (PDRBD+) and 14 without RBD (PDRBD−), and 25 control subjects underwent 11C-MeNER PET. iRBD patients also had 18F-DOPA PET. Volume-of-interest analyses and voxel-level statistical parametric mapping were performed.ResultsPartial-volume corrected 11C-MeNER binding potential (BPND) values in M1S1 differed across the groups (P = 0.022) with the iRBD and PDRBD+ groups showing significant reductions (controls vs. iRBD P = 0.007; control vs. PDRBD+ P = 0.008). Voxel-wise comparisons confirmed reductions of M1S1 11C-MeNER binding in PD and iRBD patients. Significant correlation was seen between putaminal 18F-DOPA uptake and thalamic 11C-MeNER binding in iRBD patients (r2 = 0.343, P = 0.013).ConclusionsThis study found altered noradrenergic neurotransmission in the M1S1 cortex of iRBD patients. The observed reduction of M1S1 11C-MeNER binding in iRBD may represent noradrenergic terminal degeneration or physiological down-regulation of NARTs in this prodromal phenotype of PD. The correlation between thalamic 11C-MeNER binding and putaminal 18F-DOPA binding suggests that these neurotransmitter systems degenerate in parallel in the iRBD phenotype of prodromal PD. 相似文献
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《Sleep medicine》2020
ObjectiveObstructive sleep apnea (OSA) is a high prevalent disorder with severe consequences including sleepiness, metabolic, and cardiovascular disorders. The aim of this study was to assess the effect of an individualized exercise-training (IET) program with educational sessions vs educational sessions alone on severity markers of OSA over an eight-week duration.MethodsThis was a randomised, controlled, parallel-design study. In sum, 64 patients with moderate-to-severe OSA (apnea-hypopnea index AHI 15–45/hour), low physical activity level (Voorrips<9), body-mass index (BMI) <40 kg/m2 were included in intervention group (IG) or control group (CG), and 54 patients finished the study. All underwent polysomnography (PSG), multiple sleep latency test (MSLT), constant workload exercise test, blood samples and fulfilled questionnaires twice. The primary endpoint was the change in apnea-hypopnea (AHI) at eight weeks from baseline. Main secondary endpoints were daytime sleepiness assessed by questionnaire and objective tests.ResultsNo significant between-group differences were found for changes in AHI. A reduction in AHI was found in IG only (p = 0.005). Compared to CG, exercise training leads to a greater decrease in AHI during REM sleep (p = 0.0004), with a significant increase in mean daytime sleep latency (p = 0.02). Between-group differences were significant for weight reduction, severity of fatigue, insomnia and depressive symptoms with trend for sleepiness symptoms.ConclusionsIn adult patients with moderate-to-severe OSA, IET did not decrease AHI compared to the control group but improved markers of severity of OSA, in particular AHI in rapid eye movement (REM) sleep and objective daytime sleepiness. Adding personalized exercise training to the management of patients with OSA should be considered.ClinicalTrials.gov identifierNCT01256307. 相似文献
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6.
Rishi Sharma Rosa Rademakers Bradley F. Boeve Ronald C. Petersen David T. Jones 《Neurocase》2019,25(1-2):17-20
Hereditary diffuse leukoencephalopathy with spheroids (HDLS) is an adult-onset autosomal dominant leukoencephalopathy resulting from mutations affecting the tyrosine kinase domain of the colony stimulating factor receptor 1 protein (encoded by CSF1R). The clinical phenotypes reported with CSF1R mutations are variable. We present a case of a patient with a pathogenic variant in the CSF1R gene with clinical and imaging features suggestive of Dementia with Lewy Bodies (DLB). This case expands the known clinical presentations associated with CSF1R mutations. 相似文献
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8.
《Sleep medicine》2021
ObjectiveSleep complaints are frequent after acute COVID-19. Aim of this study was to videopolysomnographically evaluate sleep and sleep disorders after SARS-Cov2 infection.MethodsPatients with suspected sleep disorders after acute COVID-19 underwent video-polysomnography (v-PSG) at the Sleep Disorders Clinic, Department of Neurology, Medical University Innsbruck. V-PSG was conducted 4.2 (SD = 1.3) months after diagnosis of SARS-CoV-2 infection.ResultsEleven patients [nine men, age 52.5 (SD = 11.7) years; BMI 29 (SD = 5.2) kg/m2] were included. At 60 days follow-up after diagnosis, persisting breathing complaints were present in 7/11 (64%) patients. After v-PSG four patients (36%) were diagnosed with obstructive sleep apnea (OSA). Respiratory frequency during sleep was normal and no tachypnea, thoracoabdominal asynchrony, or periodic deep sighing were detected. Four patients (36%) showed REM sleep without atonia (RWA), and two additional patients showed an RWA index within the highest range of normality.ConclusionWe report videopolysomnographic findings in a series of eleven patients after acute COVID-19. A major finding of this study was the presence of isolated RWA, a recognized prodromal stage of RBD, in more than one third of the patients. Future videopolysomnographic investigations including quantification of RWA in patients after COVID-19 will give more insights into a possible acute or post-infectious CNS pathology related to the SARS-CoV-2 infection. 相似文献
9.
Sabine Gretenkord Bas M. J. Olthof Myrto Stylianou Adrian Rees Sarah E. Gartside Fiona E. N. LeBeau 《The European journal of neuroscience》2020,52(2):2915-2930
The role of dopamine in regulating sleep‐state transitions during, both natural sleep and under anaesthesia, is still unclear. Recording in vivo in the rat mPFC under urethane anaesthesia, we observed predominantly slow wave activity (SWA) of <1 Hz in the local field potential interrupted by occasional spontaneous transitions to a low‐amplitude‐fast (LAF) pattern of activity. During periods of SWA, transitions to LAF activity could be rapidly and consistently evoked by electrical stimulation of the ventral tegmental area (VTA). Spontaneous LAF activity, and that evoked by stimulation of the VTA, consisted of fast oscillations similar to those seen in the rapid eye movement (REM)‐like sleep state. Spontaneous and VTA stimulation‐evoked LAF activity occurred simultaneously along the dorsoventral extent of all mPFC subregions. Evoked LAF activity depended on VTA stimulation current and could be elicited using either regular (25–50 Hz) or burst stimulation patterns and was reproducible upon repeated stimulation. Simultaneous extracellular single‐unit recordings showed that during SWA, presumed pyramidal cells fired phasically and almost exclusively on the Up state, while during both spontaneous and VTA‐evoked LAF activity, they fired tonically. The transition to LAF activity evoked by VTA stimulation depended on dopamine D1‐like receptor activation as it was almost completely blocked by systemic administration of the D1‐like receptor antagonist SCH23390. Overall, our data demonstrate that activation of dopamine D1‐like receptors in the mPFC is important for regulating sleep‐like state transitions. 相似文献