Search

Introduction Track density imaging (TDI) has been proven to be a useful approach able to investigate white matter (WM) anatomical integrity in several neurodegenerative conditions, such as Parkinson's disease (PD) and classical phenotype of Progressive Supranuclear Palsy (PSP) also known as Richardson's syndrome (RS). To the best of our knowledge, no studies have assessed WM changes in PSP-predominant parkinsonism (PSP–P) patients by using a TDI approach, and no studies have explored the potential role of these changes in discriminating patients with PSP-P from those with PSP-RS and PD. Methods We used TDI to characterize WM changes in 31 PSP-P compared to 36 PSP-RS, 36 PD and 37 healthy controls (HC). Then, a support vector machine (SVM) approach was used to evaluate the performance of TDI in discriminating between patient groups. Results Relative to HC and PD patients, decreased track density in PSP-P patients was found in several WM regions such as the midbrain, superior cerebellar peduncles, cerebellum and corticospinal tract. By contrast, higher values of track density were observed in PSP-P patients compared to PSP-RS. SVM approach using TDI differentiated patients with PSP-P from PD and PSP-RS with an area under the curve of 0.90 and 0.76, respectively. Conclusions Our findings suggest that TDI may represent a useful approach for characterizing WM changes in PSP-P patients representing a potential new MRI biomarker in distinguishing this PSP phenotype from PD.

Objective To investigate heart rate variability (HRV) in patients with Essential Tremor (ET) in comparison with patients with Parkinson's Disease (PD). Methods This is a cross sectional control study including 10 patients with ET, 10 patients with PD and 10 age-sex-matched controls. In patients and controls, we measured the components of HRV analysis in the frequency domain during a daytime period of 12-h. Selected HRV variables were low-frequency (LF) and high-frequency (HF), conventionally considered to be influenced by the sympathetic system and the parasympathetic system respectively. Results HRV variables, in patients with ET, were significantly different from those detected in PD patients and similar to those of controls while in PD patients, they were significantly different from those of controls. At cut off level of 654 ms 2 , LF component correctly distinguished ET patients versus PD with sensitivity, specificity, PPV and accuracy of 100%. By contrast, at cut off level of 737 ms 2 , HF component showed sensitivity, specificity, PPV and accuracy of 80%, 100%, 100%, and 86.67% respectively. DAT-SPECT and cardiac MIBG uptake were both normal in ET patients whereas they were markedly decreased in those with PD. Conclusions In our study, the LF component of HRV analysis distinguishes ET patients from those with PD on an individual basis, thus representing a valid help in everyday clinical practice for differentiation between these patients in absence of scintigraphic investigations.

Background Parkinson's disease (PD) is the second most common neurodegenerative disorder, and the most common neurodegenerative form of parkinsonism. Recently, a pathogenic mutation (p.N855S) in DNAJC13 was linked to autosomal dominant Lewy body PD in a Dutch–German–Russian Mennonite multi-incident kindred, and was found in five additional patients. In this study, we performed a comprehensive screening of the DNAJC13 gene in familial PD and sporadic PD to assess the frequency of known and novel rare nonsynonymous variants. Methods We screened 563 sporadic and 168 familial PD patients and a control series (n = 1000) for the coding region of DNAJC13. Results Our sequencing analysis identified two carriers of the c.2708G > A (p.R903K) variant in exon 24 of DNAJC13. One of these carriers is a familial PD. Conclusion The p. R903K variant was not found in 1000 healthy controls and it is localized in a functional domain of the DNAJC13 protein. Further studies are necessary to evaluate the role of DNAJC13 variants in PD.