Botulinum Toxin Effects on Freezing of Gait in Parkinson's Disease: A Systematic Review.

Freezing of gait is a frequent phenomenon and can be one of the most debilitating motor impairments in Parkinson's disease, especially in the advanced stages. It is currently defined as a brief episodic absence or any marked reduction in the forward progression of the feet, despite the intention to walk. Greater severity of freezing of gait has been associated with more frequent falls, postural instability, and executive dysfunction.

Research advancement in fluid biomarkers for Parkinson's disease.

Introduction: Diagnostic criteria for Parkinson's disease (PD) rely on clinical, mainly motor, features, implying that pre-motor phase cannot be accurately identified. To achieve a reliable early diagnosis, similar to what has been done for Alzheimer's disease (AD), a shift from clinical to biological identification of PD is being pursued. This shift has taken great advantage from the research on cerebrospinal fluid (CSF) biomarkers as they mirror the ongoing molecular pathogenic mechanisms taking place in PD, thus intercepting the disease timely with respect to clinical manifestations.

Hyposmia correlates with axial signs and gait disorder in Parkinson's disease: an Italian Olfactory Identification Test study.

Background: Olfactory dysfunction is a non-motor symptom and an important biomarker of Parkinson's disease (PD) because of its high prevalence (> 90%). Whether hyposmia correlates with motor symptoms is unclear. In the present study, we aim to investigate the relationship between olfactory impairment with both motor and non-motor features and disease variables (disease duration, stage, and severity).

Alpha-synuclein in Parkinson's disease and other synucleinopathies: from overt neurodegeneration back to early synaptic dysfunction.

Although the discovery of the critical role of α-synuclein (α-syn) in the pathogenesis of Parkinson's disease (PD) is now twenty-five years old, it still represents a milestone in PD research. Abnormal forms of α-syn trigger selective and progressive neuronal death through mitochondrial impairment, lysosomal dysfunction, and alteration of calcium homeostasis not only in PD but also in other α-syn-related neurodegenerative disorders such as dementia with Lewy bodies, multiple system atrophy, pure autonomic failure, and REM sleep behavior disorder. Furthermore, α-syn-dependent early synaptic and plastic alterations and the underlying mechanisms preceding overt neurodegeneration have attracted great interest.

Corticospinal tract abnormalities and ventricular dilatation: A transdiagnostic comparative tractography study.

Background: Microstructural alterations of corticospinal tract (CST) have been found in idiopathic normal pressure hydrocephalus (iNPH). No study, however, investigated the effect of ventricular dilatation on CST in Progressive Supranuclear Palsy (PSP).

Objective: The aim of this study was to investigate CST diffusion profile in a large cohort of PSP patients with and without ventricular dilatation.

Sudden Onset, Fixed Dystonia and Acute Peripheral Trauma as Diagnostic Clues for Functional Dystonia.

Background: The differentiation of functional dystonia from idiopathic dystonia may be clinically challenging.

Objective: To identify clinical features suggestive of functional dystonia to guide physicians to distinguish functional dystonia from idiopathic dystonia.

Methods: Patient data were extracted from the Italian Registry of Functional Motor Disorders and the Italian Registry of Adult Dystonia.

Progressive supranuclear palsy with marked ventricular dilatation mimicking normal pressure hydrocephalus.

Background: Progressive supranuclear palsy (PSP) patients can show ventricular enlargement mimicking normal pressure hydrocephalus (NPH). The aim of this study was to distinguish PSP patients with marked ventricular dilatation (PSP-vd) from those with normal ventricular system and to evaluate the coexistence of NPH in PSP-vd patients.

Methods: One hundred three probable PSP patients, 18 definite NPH patients, and 41 control subjects were enrolled in the study.

Blink reflex recovery cycle distinguishes patients with idiopathic normal pressure hydrocephalus from elderly subjects.

Background: The R2 component of blink reflex recovery cycle (R2BRrc) is a simple neurophysiological tool to detect the brainstem hyperexcitability commonly occurring in several neurological diseases such as Parkinson's disease and atypical parkinsonisms. In our study, we investigated for the first time the usefulness of R2BRrc to assess brainstem excitability in patients with idiopathic Normal Pressure Hydrocephalus (iNPH) in comparison with healthy subjects.

Methods: Eighteen iNPH patients and 25 age-matched control subjects were enrolled.

Incidental evidence of hypointensity in brain grey nuclei on routine MR imaging: when to suspect a neurodegenerative disorder?

Deep grey nuclei of the human brain accumulate minerals both in aging and in several neurodegenerative diseases. Mineral deposition produces a shortening of the transverse relaxation time which causes hypointensity on magnetic resonance (MR) imaging. The physician often has difficulties in determining whether the incidental hypointensity of grey nuclei seen on MR images is related to aging or neurodegenerative pathology.

Alpha-synuclein targets GluN2A NMDA receptor subunit causing striatal synaptic dysfunction and visuospatial memory alteration.

Parkinson's disease is a progressive neurodegenerative disorder characterized by altered striatal dopaminergic signalling that leads to motor and cognitive deficits. Parkinson's disease is also characterized by abnormal presence of soluble toxic forms of α-synuclein that, when clustered into Lewy bodies, represents one of the pathological hallmarks of the disease. However, α-synuclein oligomers might also directly affect synaptic transmission and plasticity in Parkinson's disease models.

Dopamine D2 receptor activation potently inhibits striatal glutamatergic transmission in a G2019S LRRK2 genetic model of Parkinson's disease.

Among genetic abnormalities identified in Parkinson's disease (PD), mutations of the leucine-rich repeat kinase2 (LRRK2) gene, such as the G2019S missense mutation linked to enhanced kinase activity, are the most common. While the complex role of LRRK2 has not been fully elucidated, evidence that mutated kinase activity affects synaptic transmission has been reported. Thus, our aim was to explore possible early alterations of neurotransmission produced by the G2019S LRRK2 mutation in PD.