Abnormal intrinsic brain functional network dynamics in Parkinson’s disease

Brain, Journal Year: 2017, Volume and Issue: 140(11), P. 2955 - 2967

Published: Sept. 5, 2017

See Nieuwhof and Helmich (doi:10.1093/brain/awx267) for a scientific commentary on this article. Parkinson's disease is neurodegenerative disorder characterized by nigrostriatal dopamine depletion. Previous studies measuring spontaneous brain activity using resting state functional magnetic resonance imaging have reported abnormal changes in broadly distributed whole-brain networks. Although connectivity, estimating temporal correlations between regions, measured with the assumption that intrinsic fluctuations throughout scan are stable, dynamic of connectivity recently been suggested to reflect aspects capacity neural systems, thus may serve as biomarkers disease. The present work first study investigate patients disease, focus properties states well variability network topological organization imaging. Thirty-one 23 healthy controls were studied group spatial independent component analysis, sliding windows approach, graph-theory methods. analyses two discrete configurations: more frequent, sparsely connected within-network (State I) less strongly interconnected between-network II). In occurrence State I dropped 12.62%, while expression II increased same amount. This was consistent altered shortening dwell time proportional increase pattern II. These suggestive reduction segregation among networks correlated clinical severity symptoms. Additionally, there higher global efficiency, suggesting an integration confirmed vulnerability

Language: Английский

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Glutamate-induced excitotoxicity in Parkinson's disease: The role of glial cells

Journal of Pharmacological Sciences, Journal Year: 2020, Volume and Issue: 144(3), P. 151 - 164

Published: Aug. 1, 2020

Glutamate is the major excitatory neurotransmitter in central nervous system. transmission efficiency depends on correct functionality and expression of a plethora receptors transporters, located both neurons glial cells. Of note, glutamate reuptake by dedicated transporters prevents its accumulation at synapse as well non-physiological spillover. Indeed, extracellular increase causes aberrant synaptic signaling leading to neuronal excitotoxicity death. Moreover, extrasynaptic diffusion strongly associated with glia reaction neuroinflammation. Glutamate-induced mainly linked an impaired ability cells respond glutamate, then this considered common hallmark many neurodegenerative diseases, including Parkinson's disease (PD). In review, we discuss function astrocytes microglia homeostasis, focusing how dysfunction glutamate-induced neurodegeneration PD.

Language: Английский

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Magnetic resonance imaging for the diagnosis of Parkinson’s disease

Journal of Neural Transmission, Journal Year: 2017, Volume and Issue: 124(8), P. 915 - 964

Published: April 4, 2017

The differential diagnosis of parkinsonian syndromes is considered one the most challenging in neurology and error rates clinical can be high even at specialized centres. Despite several limitations, magnetic resonance imaging (MRI) has undoubtedly enhanced diagnostic accuracy neurodegenerative parkinsonism over last three decades. This review aims to summarize research findings regarding value different MRI techniques, including advanced sequences high- ultra-high-field modern image analysis algorithms, work-up Parkinson's disease. includes not only exclusion alternative diagnoses for disease such as symptomatic atypical parkinsonism, but also early, new onset, prodromal

Language: Английский

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Parkinson's disease: Cause factors, measurable indicators, and early diagnosis

Computers in Biology and Medicine, Journal Year: 2018, Volume and Issue: 102, P. 234 - 241

Published: Sept. 20, 2018

Language: Английский

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Complex Brain Network Analysis and Its Applications to Brain Disorders: A Survey

Complexity, Journal Year: 2017, Volume and Issue: 2017, P. 1 - 27

Published: Jan. 1, 2017

It is well known that most brain disorders are complex diseases, such as Alzheimer’s disease (AD) and schizophrenia (SCZ). In general, regions their interactions can be modeled network, which describe highly efficient information transmission in a brain. Therefore, network analysis plays an important role the study of diseases. With development noninvasive neuroimaging electrophysiological techniques, experimental data produced for constructing networks. recent years, researchers have found networks constructed by using many topological properties, small-world property, modularity, rich club. More importantly, been to associated with abnormal structures These findings provide not only new perspective explore pathological mechanisms disorders, but also guidance early diagnosis treatment disorders. The purpose this survey comprehensive overview its applications

Language: Английский

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Axonal damage and loss of connectivity in nigrostriatal and mesolimbic dopamine pathways in early Parkinson's disease

NeuroImage Clinical, Journal Year: 2017, Volume and Issue: 14, P. 734 - 740

Published: Jan. 1, 2017

A progressive loss of dopamine neurons in the substantia nigra (SN) is considered main feature idiopathic Parkinson's disease (PD). Recent neuropathological evidence however suggests that axons nigrostriatal dopaminergic system are earliest target α-synuclein accumulation PD, thus principal site for vulnerability. Whether this applies to vivo and also mesolimbic has not been investigated yet. We used [11C]FeCIT PET measure presynaptic transporter (DAT) activity both systems, 36 early PD patients (mean duration months ± SD 21.8 10.7) 14 healthy controls similar age. performed anatomically-driven partial correlation analysis evaluate possible changes connectivity within networks at an clinical phase. In system, we found a severe DAT reduction afferents dorsal putamen (DPU) (η2 = 0.84), whereas SN was less affected region 0.31). ventral tegmental area (VTA) striatum (VST) were reduced patient group, but lesser degree (VST η2 0.71 VTA compared controls, there marked decrease network between DPU nodes, supporting significant derangement pathway. These results suggest neurodegeneration pathways initially more prominent afferent system. Considering as disconnection syndrome starting from axons, it would justify neuroprotective interventions even if have already manifested symptoms.

Language: Английский

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Deep Brain Stimulation: A Paradigm Shifting Approach to Treat Parkinson's Disease

Frontiers in Neuroscience, Journal Year: 2016, Volume and Issue: 10

Published: April 27, 2016

Parkinson disease (PD) is a chronic and progressive movement disorder classically characterized by slowed voluntary movements, resting tremor, muscle rigidity, impaired gait balance. Medical treatment highly successful early on, though the majority of people experience significant complications in later stages. In advanced PD, when medications no longer adequately control motor symptoms, deep brain stimulation (DBS) offers powerful therapeutic alternative. DBS involves surgical implantation one or more electrodes into specific areas brain, which modulate disrupt abnormal patterns neural signaling within targeted region. Outcomes are often dramatic following DBS, with improvements function reductions having been repeatedly demonstrated. Given such robust responses, emerging indications for being investigated. parallel expansions scope, advancements neurosurgical technique precision delivery have recently broadened as well. This review focuses on revolutionary addition to armamentarium summarizes technological neuroimaging biomedical engineering intended improve targeting, programming, overall management.

Language: Английский

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Clinical and Imaging Markers of Prodromal Parkinson's Disease

Frontiers in Neurology, Journal Year: 2020, Volume and Issue: 11

Published: May 8, 2020

The diagnosis of Parkinson's disease (PD) relies on the clinical effects dopamine deficiency, including bradykinesia, rigidity and tremor, usually manifesting asymmetrically. Misdiagnosis is common, due to overlap symptoms with other neurodegenerative disorders such as multiple system atrophy progressive supranuclear palsy, only autopsy can definitively confirm disease. Motor deficits generally appear when 50-60% dopaminergic neurons in substantia nigra are already lost, limiting effectiveness potential neuroprotective therapies. Today, we consider PD be not just a movement disorder, but rather complex syndrome non-motor (NMS) sleep-wake cycle regulation, cognitive impairment, mood affect, autonomic dysfunction, sensory pain. Symptomatic LRRK2 mutation carriers share features individuals sporadic PD, hyposmia, constipation, impaired color discrimination, depression, sleep disturbance. Following assumption that pre-symptomatic gene will eventually exhibit symptoms, their neuroimaging results extended stage PD. long latent phase termed prodromal-PD, represents an opportunity for early recognition incipient Early could allow initiation possible therapies at might most effective. number markers sufficient level evidence included MDS research criteria prodromal have increased during last ten years. Here, review approach emphasis imaging report from our study, retrospective evaluation cohort 39 participants who underwent DAT-SPECT scan part follow up. study was carried out see if it detect subclinical signs preclinical (neurodegenerative processes commenced, there no evident or signs) (symptoms present, yet insufficient define disease) stages

Language: Английский

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Classifying Parkinson’s Disease Based on Acoustic Measures Using Artificial Neural Networks

Sensors, Journal Year: 2018, Volume and Issue: 19(1), P. 16 - 16

Published: Dec. 20, 2018

In recent years, neural networks have become very popular in all kinds of prediction problems. this paper, multiple feed-forward artificial (ANNs) with various configurations are used the Parkinson's disease (PD) tested individuals, based on extracted features from 26 different voice samples per individual. Results validated via leave-one-subject-out (LOSO) scheme. Few feature selection procedures Pearson's correlation coefficient, Kendall's principal component analysis, and self-organizing maps, been for boosting performance algorithms data reduction. The best test accuracy result has achieved coefficient-based selection, most relevant recognized. Multiple ANNs proven to be classification technique diagnosis PD without usage procedure (on raw data). Finally, a network is fine-tuned, 86.47% was achieved.

Language: Английский

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Diminished EEG habituation to novel events effectively classifies Parkinson’s patients

Clinical Neurophysiology, Journal Year: 2017, Volume and Issue: 129(2), P. 409 - 418

Published: Dec. 13, 2017

Language: Английский

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