Accumulation Area of a Japanese PRNP P102L Variant Associated With Gerstmann-Sträussler-Scheinker Disease: The Ariake PRNP P102L Variant.

BACKGROUND AND PURPOSE: The coast of Kyushu Island on Ariake Sea in Japan is known to be an accumulation area for patients with a proline-to-leucine substitution mutation at residue 102 (P102L) of the human prion protein gene (PRNP), which is associated with Gerstmann-Sträussler-Scheinker disease. We designated this geographical distribution as the "Ariake PRNP P102L variant." The purpose of this study was to characterize the clinical features of this variant. METHODS: We enrolled patients with the PRNP P102L variant who were followed up at the Saga University Hospital from April 2002 to November 2019. The clinical information of patients were obtained from medical records, including clinical histories, brain magnetic resonance imaging (MRI), and electroencephalography (EEG). A brain autopsy was performed on one of the participants. RESULTS: We enrolled 24 patients from 19 family lines, including 12 males. The mean age at symptom onset was 60.6 years (range, 41-77 years). The incidence rate of the Ariake PRNP P102L variant was 3.32/1,000,000 people per year in Saga city. The initial symptoms were ataxia (ataxic gait or dysarthria) in 19 patients (79.2%), cognitive impairment in 3 (12.5%), and leg paresthesia in 2 (8.3%). The median survival time from symptom onset among the 18 fatal cases was 63 months (range, 23-105 months). Brain MRI revealed no localized cerebellar atrophy, but sparse diffusion-weighted imaging abnormalities were detected in 16.7% of the patients. No periodic sharp-wave complexes were identified in EEG. Neuropathological investigations revealed uni- and multicentric prion protein (PrP) plaques in the cerebral cortex, putamen, thalamus, and cerebellum of one patient. Western blot analysis revealed 8-kDa proteinase-K-resistant PrP. CONCLUSIONS: This is the first report of the accumulation area of a PRNP P102L variant on the coast of Ariake Sea. The Ariake PRNP P102L variant can be characterized by a relatively long disease duration with sparse abnormalities in brain MRI and EEG relative to previous reports. Detailed interviews to obtain information on the birthplace and the family history of related symptoms are important to diagnosing a PRNP P102L variant.

Associations for progression of cerebral small vessel disease burden in healthy adults: the Kashima scan study.

To investigate the association between vascular risk factors and progression of cerebral small vessel disease (SVD), we conducted a longitudinal study with neurologically healthy cohort composed mostly of middle-aged adults (n = 665, mean age, 57.7 years). Subjects, who had both baseline data of brain health examinations including MRI and follow-up MRI at least 1 year after the baseline MRI, were included this study. The presence of features of SVD, including lacunes, cerebral microbleeds, white matter hyperintensity, and basal ganglia perivascular spaces were summed to obtain "total SVD score" (range, 0-4). Progression of SVD was evaluated among subjects with a total SVD score of ≤ 3 and was defined as a ≥ 1 point increase in that score at follow-up relative to baseline. As the primary analysis, multivariate logistic regression analyses were performed to determine the associations of progression of SVD at baseline. The median follow-up period was 7.3 years and progression of SVD was observed in 154 subjects (23.2%). Even after adjustment with confounders multivariate logistic regression analyses showed that progression of SVD was associated with age (per 10-year increase, odds ratio [OR]: 2.08, 95% confidence interval [CI] 1.62-2.67), hypertension (OR 1.55, 95%CI 1.05-2.29), systolic blood pressure (BP) (per standard deviation [SD] increase, OR 1.27, 95%CI 1.04-1.54), diastolic BP (per SD increase, OR 1.23, 95%CI 1.01-1.50), and mean arterial pressure (per SD increase, OR 1.27, 95%CI 1.04-1.55). Age and high blood pressure appear to play key roles in the progression of cerebral small vessel burden after mid-life.

Hypertension, cerebral Amyloid, aGe Associated Known neuroimaging markers of cerebral small vessel disease Undertaken with stroke REgistry (HAGAKURE) prospective cohort study: Baseline characteristics and association of cerebral small vessel disease with prognosis in an ischemic stroke cohort.

Introduction: Cerebral small vessel disease (SVD) is one of the leading causes of stroke; each neuroimaging marker of SVD is correlated with vascular risk factors and associated with poor prognosis after stroke. However, longitudinal studies investigating the association between comprehensive SVD burden scoring system, "total SVD score" - which encompasses the established neuroimaging markers of lacunae, cerebral microbleeds (CMBs), white matter hyperintensities (WMH) including periventricular hyperintensities, and perivascular spaces in basal ganglia- and clinical outcomes are limited. The aim of this study is to determine the association between SVD burden and long-term prognosis in patients with ischemic stroke. Methods and design: This prospective, single-center, observational study enrolled patients with acute ischemic stroke, including cerebral infarction and transient ischemic attack. Magnetic resonance imaging scans were performed, and then total SVD score (range, 0-4) was calculated. We recorded baseline characteristics and evaluated the relationships of long-term outcomes to SVD neuroimaging markers and total SVD score. Stroke recurrence was thought as primary outcome. Hazard ratios (HRs) of events during follow-up were calculated using Cox proportional hazards modeling with adjustments for age, sex, hypertension, dyslipidemia, diabetes mellitus, atrial fibrillation, and smoking. Cumulative event rates were estimated using the Kaplan-Meier method. Results: Consecutive 564 acute ischemic stroke patients were enrolled according to inclusion and exclusion criteria. A total of 467 participants with first-ever ischemic stroke were analyzed (median age 75.0 [interquartile range, 64.0-83.0] years, 59.3% male). Total SVD score was 0 point in 47 individuals (12.0%), 1 point in 83 (21.2%), 2 points in 103 (26.3%), 3 points in 85 (21.7%), and 4 points in 73 (18.7%). Twenty-eight recurrent stroke events were identified during follow-up. Total SVD score ≥ 2, presence of CMBs, and moderate-to-severe WMH were associated with increased risk of recurrent stroke events (HR 9.31, 95% confidence interval [CI] 2.33-64.23; HR 2.81, 95% CI 1.08-7.30; HR 2.90, 95% CI 1.22-6.88, respectively). Conclusion: The accumulation of SVD biomarkers as determined by total SVD score offered a reliable predictor of stroke recurrence. This study established a firm understanding of SVD prognosis in clinical settings.

Chédiak-Higashi syndrome presenting as a hereditary spastic paraplegia.

Hereditary spastic paraplegias (HSPs) comprise a group of neurodegenerative disorders characterized by weakness and leg spasticity. LYST is responsible for Chédiak-Higashi syndrome (CHS), which exhibits partial oculocutaneous albinism, primary immunodeficiency, and bleeding tendency in childhood. Although neurological symptoms of CHS also appear in adulthood, a phenotype of spastic paraplegia has rarely been reported in CHS. In this study, we investigated LYST mutations in 387 HSP patients through the Japan Spastic Paraplegia Research Consortium to clarify the frequency of LYST mutations in HSP, finding six adult patients with LYST mutations in four HSP families. They exhibited intellectual disability, cerebellar ataxia, neuropathy, and pyramidal signs. Meanwhile, only 15 patients with CHS in childhood have been revealed in a decade by a nationwide survey in Japan. Thus, LYST mutations might indicate a HSP phenotype in a considerable number of adult patients with CHS.

Low-Dose Phosphodiesterase III Inhibitor Reduces the Vascular Amyloid Burden in Amyloid-ß Protein Precursor Transgenic Mice.

A previous study reported that relatively high-dose cilostazol (0.3%) promoted the drainage of cerebrovascular amyloid-ß (Aß) protein in Aß Precursor Protein (APP) transgenic mice overexpressing vasculotropic Aß. We investigated whether lower-dose cilostazol can decrease micro-hemorrhages and Aß deposition in the brain using APP transgenic mice. At baseline, 14-month-old female Tg2576 mice were randomly assigned to a control group (vehicle), aspirin group (0.01% aspirin), or cilostazol group (0.01% cilostazol). The severity of cerebral micro-hemorrhages (i.e., number), area of senile plaque, and severity of vascular amyloid burden (quantified with cerebral amyloid angiopathy (CAA) score (=number of Aß-positive vessels × severity of amyloid burden of Aß-positive vessels) were evaluated in the brain of mice aged 15 and 21-23 months. At 15 months, no differences were shown in each pathological change among the three groups. At 21-23 months, there were no differences in the severity of cerebral micro-hemorrhages or area of senile plaque among the three groups. However, the CAA score was significantly lower in the cilostazol compared to the control group (p = 0.046, Mann-Whitney U test), although no difference was seen between the control and aspirin group. Our study showed that lower-dose cilostazol could reduce the vascular amyloid burden without increasing cerebral micro-hemorrhages in APP transgenic mice.

Total small vessel disease score and cerebro-cardiovascular events in healthy adults: The Kashima scan study.

BACKGROUND AND AIMS: We explored the association between the total small vessel disease score obtained from baseline magnetic resonance imaging and subsequent cerebro-cardiovascular events in neurologically healthy Japanese adults. METHODS: The presence of small vessel disease features, including lacunae, cerebral microbleeds, white matter changes, and basal ganglia perivascular spaces on magnetic resonance imaging, was summed to obtain a "total small vessel disease score" (range, 0-4). After excluding participants with previous stroke or ischemic heart disease, intracranial artery stenosis (≥50%), or cerebral aneurysm (≥4 mm), a total of 1349 participants (mean age, 57.7 years; range, 22.8-85.0 years; 46.9% male) were classified into three groups by total small vessel disease score: 0 (n = 984), 1 (n = 269), and ≥2 (n = 96). Cerebro-cardiovascular events (i.e., any stroke, transient ischemic attack, ischemic heart disease, acute heart failure, and aortic dissection) were defined as the primary end point. The hazard ratio (HR) of events during follow-up was calculated using Cox proportional hazards modeling with adjustments for age, sex, hypertension, diabetes mellitus, and smoking. Cumulative event-free rates were estimated using the Kaplan-Meier method. RESULTS: During follow-up (mean, 6.7 years), 35 cerebro-cardiovascular (16 cerebrovascular) events were identified. Higher small vessel disease score was associated with increased risk of cerebro-cardiovascular events (HR per unit increase, 2.17; 95% confidence interval, 1.36-3.46; P = 0.001). Events were more frequent among participants with higher score (P < 0.001, log-rank test). CONCLUSIONS: This study offered additional evidence for the clinical relevance of total small vessel disease score, suggesting the score as a promising tool to predict the risk of subsequent vascular events even in healthy populations.

Synergistic effect of hypertension and smoking on the total small vessel disease score in healthy individuals: the Kashima scan study.

The total cerebral small vessel disease (SVD) score is a proposed comprehensive index of SVD severity in the brain. However, data on lifestyle-related risk factors affecting SVD scores are limited. We conducted a cross-sectional study with 858 neurologically healthy adults who underwent brain magnetic resonance imaging (MRI). Information on clinical and lifestyle-related risk factors was obtained from health screenings. The SVD score (0-4) was calculated from the presence of lacunes, cerebral microbleeds, moderate to severe white matter lesions, and basal ganglia perivascular spaces on MRI. Subjects were divided into two groups by SVD score; potential risk factors and their joint effects in the two groups were assessed by logistic regression. Biologic interactions were estimated using the synergy index. After adjustment for possible confounders, the adjusted odds ratio for moderate to severe SVD scores (SVD score ≥ 2) was 1.12 (95% confidence interval (CI) 1.08-1.16) for age per year, 1.33 (95% CI 1.02-1.74) for body mass index per standard deviation, 3.39 (95% CI 1.90-6.03) for hypertension, 2.31 (95% CI 1.14-4.69) for diabetes, and 2.35 (95% CI 1.10-5.02) for smoking. Hypertension and current smoking had a synergistic effect on the risk of moderate to severe SVD (OR 10.59, 95% CI 3.97-28.3; synergy index 4.03, 95% CI 1.17-28.30), and the combination of hypertension and diabetes had an additive effect on the risk of moderate to severe SVD (OR 9.48, 95% CI 3.80-23.66; synergy index 2.12, 95% CI 0.68-6.67). Therefore, combined strategies for managing hypertension, smoking, and diabetes may be effective for preventing SVD.