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Background: The imbalance between the production and clearance of alpha-synuclein and its consequent accumulation plays a pivotal role in the pathogenesis of Parkinson's disease (PD). The diminished clearance of alpha-synuclein may be partly attributable to impaired interstitial fluid, which can be reflected by the extent of dilated perivascular space (dPVS). We studied the association between dPVS and dopamine neuronal degeneration. Method: We screened 71 healthy controls (HCs) and 88 patients from the Parkinson Progression Markers Initiative (PPMI) database. The dPVS was evaluated in different brain regions on axial T2-weighted images, and dopamine transporter (DAT) imaging data was used to elucidate the extent of dopaminergic neuronal degeneration. Patients with PD were further divided into two groups (SN + PD and SN - PD groups) according to whether dPVS was observed in the substantia nigra (SN). DAT uptake values and clinical scales were compared between the patients with PD and HCs and against dPVS scores. We also investigated the correlation between baseline dPVS scores and longitudinal DAT changes. Results: Relative to the HCs, patients with PD had more dPVS in the SN and basal ganglia (BG). PD patients with dPVS in the SN region exhibited greater expression of tau protein in cerebrospinal fluid (P = 0.038) and a trend towards decreased DAT binding (P = 0.086) relative to those without SN dPVS. No correlations were found between dPVS scores and DAT uptake values or between dPVS scores and longitudinal DAT changes. Conclusion: The dPVS in the SN of patients with PD may reflect the degeneration of dopaminergic neurons.

Vaccination represents a cost-effective weapon for disease prevention and has proven to dramatically reduce the incidences of several diseases that once were responsible for significant mortality and morbidity worldwide. The nasal cavity constitutes the initial stage of the respiratory system and the first contact with inhaled pathogens. The intranasal (IN) route for vaccine administration is an attractive alternative to injection, due to the ease of administration as well as better patient compliance. Many published studies have demonstrated the safety and effectiveness of IN immunization with liquid vaccines. Currently, two liquid IN vaccines are available and both contain live attenuated influenza viruses. FluMist® was approved in 2003 in the United States, and Nasovac® H1N1 vaccine was approved in India in 2010. Preclinical studies showed that IN immunization with dry powder vaccines (DPVs) is feasible. Although there is not a commercially available DPV yet, DPVs have the inherent advantage of being relatively more stable than liquid vaccines. This review focuses on recent developments of DPVs as next-generation IN vaccines.

We investigated the narrow‐sense heritability of MRI‐visible dilated perivascular spaces (dPVS) in healthy young adult twins and nontwin siblings (138 monozygotic, 79 dizygotic twin pairs, and 133 nontwin sibling pairs; 28.7 ± 3.6 years) from the Human Connectome Project. dPVS volumes within basal ganglia (BGdPVS) and white matter (WMdPVS) were automatically calculated on three‐dimensional T2‐weighted MRI. In univariate analysis, heritability estimates of BGdPVS and WMdPVS after age and sex adjustment were 65.8% and 90.2%. In bivariate analysis, both BGdPVS and WMdPVS showed low to moderate genetic correlations (.30–.43) but high shared heritabilities (71.8–99.9%) with corresponding regional volumes, intracranial volumes, and other regional dPVS volumes. Older age was significantly associated with larger dPVS volume in both regions even after adjusting for clinical and volumetric variables, while blood pressure was not associated with dPVS volume although there was weak genetic correlation. dPVS volume, particularly WMdPVS, was highly heritable in healthy young adults, adding evidence of a substantial genetic contribution in dPVS development and differential effect by location. Age affects dPVS volume even in young adults, while blood pressure might have limited role in dPVS development in its normal range., dPVS volume, particularly WMdPVS, was highly heritable in healthy young adults, adding evidence of a substantial genetic contribution in dPVS development and differential effect by location.

Background and Purpose— The genetic contribution to dilated perivascular space (dPVS) burden—an emerging MRI marker of cerebral small vessel disease—is unknown. We measured the heritability of dPVS burden and its shared heritability with other MRI markers of cerebral small vessel disease. Methods— The study sample comprised 1597 participants from the population-based Three City (3C) Dijon Study, with brain MRI and genome-wide genotyping (mean age, 72.8±4.1 years; 61% women). dPVS burden and lacunar brain infarcts were rated on a semiquantitative scale, whereas an automated algorithm generated white matter hyperintensity volume (WMHV). We estimated dPVS burden heritability and shared heritability with WMHV and lacunar brain infarcts using the genome-wide complex trait analysis tool, on unrelated participants, adjusting for age, sex, intracranial volume, and principal components of population stratification. Results— dPVS burden was significantly correlated with WMHV and lacunar brain infarcts, the strongest correlation being found between WMHV and dPVS in basal ganglia. Heritability estimates were h 2 =0.59±0.24 ( P =0.007) for dPVS burden, h 2 =0.54±0.24 ( P =0.010) for WMHV, and h 2 =0.48±0.81 ( P =0.278) for lacunar brain infarcts. We found a nonsignificant trend toward shared heritability between dPVS and WMHV (r g =0.41±0.28; P =0.096), which seemed driven by dPVS in basal ganglia (r g =0.72±0.61; P =0.126) and not dPVS in white matter (r g =−0.10±0.36; P =0.393). A genetic risk score for WMHV based on published loci was associated with increased dPVS burden in basal ganglia ( P =0.031). Conclusions— We provide evidence for important genetic contribution to dPVS burden in older community-dwelling people, some of which may be shared with WMHV. Differential heritability patterns for dPVS in white matter and basal ganglia suggest at least partly distinct underlying biological processes.

Digital photography visiometer system (DPVS), that is video visibility instrument, is a new visibility instrument. It adopts the advanced digital photographic technology, and entirely imitates the principle of manual visibility observation with human eye. It carries on the manual visibility observation method, and overcomes the defects of the optical visibility instrument. This paper introduces the basic principles of DPVS, and shows the comparative results and observation differences between DPVS, forward scattering visibility instrument (Vaisala FD12) and manual visibility observation in complicated weather conditions. The comparative results show that DPVS, Vaisala FD12, and manual observation share the same change trend. However, in rainy days and other complicated weather conditions, the observation results of DPVS differ from that of the FD12 to some extent, while are much closer to that of manual observation. In the end of the paper, a concrete theoretical analytic conclusion on observation differences is provided.

Objective: To investigate whether the topography of dilated perivascular spaces (DPVS) corresponds with markers of particular small-vessel diseases such as cerebral amyloid angiopathy and hypertensive vasculopathy. Methods: Patients were recruited from an ongoing single-center prospective longitudinal cohort study of patients evaluated in a memory clinic. All patients underwent structural, high-resolution MRI, and had a clinical assessment performed within 1 year of scan. DPVS were rated in basal ganglia (BG-DPVS) and white matter (WM-DPVS) on T1 sequences, using an established 4-point semiquantitative score. DPVS degree was classified as high (score > 2) or low (score ≤ 2). Independent risk factors for high degree of BG-DPVS and WM-DPVS were investigated. Results: Eighty-nine patients were included (mean age 72.7 ± 9.9 years, 57% female). High degree of WM-DPVS was more frequent than low degree in patients with presence of strictly lobar microbleeds (45.5% vs 28.4% of subjects). High BG-DPVS degree was associated with older age, hypertension, and higher white matter hyperintensity volumes. In multivariate analysis, increased lobar microbleed count was an independent predictor of high degree of WM-DPVS (odds ratio [OR] 1.53 [95% confidence interval (CI) 1.06–2.21], p = 0.02). By contrast, hypertension was an independent predictor of high degree of BG-DPVS (OR 9.4 [95% CI 1–85.2], p = 0.04). Conclusions: The associations of WM-DPVS with lobar microbleeds and BG-DPVS with hypertension raise the possibility that the distribution of DPVS may indicate the presence of underlying small-vessel diseases such as cerebral amyloid angiopathy and hypertensive vasculopathy in patients with cognitive impairment.

The firing properties and projection patterns of secondary vestibular nucleus neurons involved in the vertical vestibulo-ocular pathways were investigated in alert cats. Recordings were made in the medial longitudinal fasciculus (MLF) from axons that were monosynaptically activated from the vestibular nerve. Many identified axons discharged in relation to vertical eye movements. The majority of these axons increased their firing rate for downward eye position (DPVs). During pitch rotation, the firing rate of DPVs was also related to upward head velocity, suggesting that they received monosynaptic input from the posterior canal. DPVs could be divided into two groups on the basis of their firing regularity. There was a tendency for regular DPVs to have a higher firing rate, a higher correlation for the rate-position relationship, and a larger phase lag and a smaller gain re head velocity than irregular DPVs. Spike-triggered average method and intraaxonal HRP techniques demonstrated that ipsilaterally projecting (i-) DPVs made inhibitory connections with up-on extraocular motoneurons, and contralaterally projecting (c-) DPVs made excitatory connections with down-on motoneurons. Virtually all i-DPVs were of regular type, while c-DPVs included both regular and irregular types. Stimulation of the caudal MLF at the level of the obex indicated that all the irregular c-DVPs and some of the regular c-DPVs had a collateral to the spinal cord, while none of the regular i-DPVs had such a collateral.

Twenty-nine cases of pigmented villonodular synovitis (PVS) of the knee in 27 patients were reviewed to determine characteristic roentgenographic findings. All cases met strict histologic criteria for diagnosis. Four cases were localized PVS (LPVS), and 25 cases were diffuse PVS (DPVS). Roentgenographic findings were largely in the soft tissues. Cystic invasion of bone or degenerative changes were rare, although present in some cases. When present in DPVS, these changes were most pronounced in the patellofemoral articular surface. In the cases of DPVS, large posterior tumefactions did not correlate with extraarticular extension. Clinical behavior of PVS was governed more by anatomic site and form of disease than by the severity of histologic or roentgenographic findings.