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Gerstmann–Sträussler–Scheinker (GSS) disease is an inherited prion disease characterized by dementia, cerebellar ataxia, and painful sensory disturbances. GSS is pathologically defined by the presence of amyloid plaques comprised of prion protein predominantly localized in the cerebral cortex, cerebellar cortex, and basal ganglia, resulting from mutations in the prion protein gene. This study investigated five cases of GSS P102L [GSS caused by a leucine (L) substitution of proline (P) at position 102 of the prion protein gene] with L-dopa-resistant extrapyramidal symptoms and reduced dopamine transporter single-photon emission computed tomography (DAT-SPECT) uptake. Clinical findings revealed diverse manifestations, with all cases exhibiting parkinsonism, and four patients had a vertical gaze palsy. Notably, all patients showed reduced striatal DAT-SPECT uptake, indicating neurodegeneration of the nigrostriatal system. Autopsy findings in one case confirmed prion protein plaques and dopaminergic neuron loss in the substantia nigra of a patient with GSS P102L. Additionally, reduced DAT immunostaining was observed in the putamen compared with a control. While previous studies have identified reduced DAT-SPECT and positron emission tomography uptake in Creutzfeldt-Jakob disease and fatal familial insomnia owing to nigrostriatal neurodegeneration induced by abnormal prion protein deposition, similar phenomena in GSS P102L have not been reported. This study provides support for a correlation between abnormal prion protein deposition and nigrostriatal system degeneration in GSS P102L. Our results reveal the importance of considering GSS P102L in cases of atypical Parkinsonism and abnormal DAT-SPECT results, which would serve as a valuable indicator for subsequent prion genetic testing. [ABSTRACT FROM AUTHOR]

Post-stroke intra-infarct repair promotes peri-infarct neural reorganization leading to functional recovery. Herein, we examined the remodeling of extracellular matrix proteins (ECM) that constitute the intact basal membrane after permanent middle cerebral artery occlusion (pMCAO) in mice. Among ECM, collagen type IV remained localized on small vessel walls surrounding CD31-positive endothelial cells within infarct areas. Fibronectin was gradually deposited from peri-infarct areas to the ischemic core, in parallel with the accumulation of PDGFRβ-positive cells. Cultured PDGFRβ-positive pericytes produced fibronectin, which was enhanced by the treatment with PDGF-BB. Intra-infarct deposition of fibronectin was significantly attenuated in pericyte-deficient Pdgfrb+/− mice. Phagocytic activity of macrophages against myelin debris was significantly enhanced on fibronectin-coated dishes. In contrast, laminin α2, produced by GFAP- and aquaporin 4-positive astrocytes, accumulated strongly in the boundary of peri-infarct areas. Pericyte-conditioned medium increased the expression of laminin α2 in cultured astrocytes, partly through TGFβ1. Laminin α2 increased the differentiation of oligodendrocyte precursor cells into oligodendrocytes and the expression of myelin-associated proteins. Peri-infarct deposition of laminin α2 was significantly reduced in Pdgfrb+/− mice, with attenuated oligodendrogenesis in peri-infarct areas. Collectively, intra-infarct PDGFRβ-positive cells may orchestrate post-stroke remodeling of key ECM that create optimal environments promoting clearance of myelin debris and peri-infarct oligodendrogenesis. [ABSTRACT FROM AUTHOR]

Previous studies have revealed risk for cognitive impairment in cardiovascular diseases. We investigated the relationship between degenerative changes of the brain and heart, with reference to Alzheimer's disease (AD) pathologies, cardiac transthyretin amyloid (ATTR) deposition, and cardiac fibrosis. A total of 240 consecutive autopsy cases of a Japanese population‐based study were examined. β amyloid (Aβ) of senile plaques, phosphorylated tau protein of neurofibrillary tangles, and ATTR in the hearts were immunohistochemically detected and graded according to the NIH‐AA guideline for AD pathology and as Tanskanen reported, respectively. Cerebral amyloid angiopathy (CAA) was graded according to the Vonsattel scale. Cardiac fibrosis was detected by picrosirius red staining, followed by image analysis. Cardiac ATTR deposition occurred after age 75 years and increased in an age‐dependent manner. ATTR deposition was more common, and of higher grades, in the dementia cases. We subdivided the cases into two age groups: ≤90 years old (n = 173) and >90 years old (n = 67), which was the mean and median age at death of the AD cases. When adjusted for age and sex, TTR deposition grades correlated with Aβ phase score (A2–3), the Consortium to Establish a Registry for AD score (sparse to frequent), and high Braak stage (V–VI) only in those aged ≤90 years at death. No significant correlation was observed between the cardiac ATTR deposition and CAA stages, or between cardiac fibrosis and AD pathologies. Collectively, AD brain pathology correlated with cardiac TTR deposition among the older adults ≤90 years. [ABSTRACT FROM AUTHOR]

The ubiquitin ligase F‐box and WD repeat domain‐containing 7 (FBXW7) is responsible for degrading diverse oncoproteins and is considered a tumor suppressor in many human cancers. Inhibiting FBXW7 enhances the malignant potential of several cancers. In this study, we aimed to investigate the role of FBXW7 in cholangiocarcinoma. We found that FBXW7 expression was associated with clinicopathological outcomes in cholangiocarcinoma patients. Both disease‐free and overall survival were significantly worse in the low‐FBXW7 group than in the high‐FBXW7 group (P = .001 and P < .001, respectively). Multivariate analysis with the Cox proportional hazards model indicated that FBXW7 was the most important independent prognostic factor for disease‐free (P = .006) and overall (P = .0004) survival. We also showed that the two FBXW7 substrates, NOTCH1 and myeloid cell leukemia sequence 1 (MCL1), regulate cholangiocarcinoma progression. Depletion of FBXW7 resulted in NOTCH1 accumulation and increased cholangiocarcinoma cell migration and self‐renewal. Interestingly, when cells were stimulated with cis‐diamminedichloridoplatinum(II) (cisplatin), FBXW7 suppression induced MCL1 upregulation, which reduced the sensitivity of cholangiocarcinoma cells to apoptosis, indicating that FBXW7‐mediated ubiquitylation is context‐dependent. These results indicate that FBXW7 modulates the malignant potential of cholangiocarcinoma through independent regulation of NOTCH1 and MCL1. The ubiquitin ligase FBXW7 is associated with prognostic outcome in cholangiocarcinoma patients. FBXW7 was found to regulate the migration and self‐renewal of cholangiocarcinoma cells through modulation of NOTCH1 as well as CDDP‐induced apoptosis through MCL1 accumulation for the first time in cholangiocarcinoma cells. These findings suggest that FBXW7 modulates the malignant potential of cholangiocarcinoma through two signals, NOTCH1 and MCL1. [ABSTRACT FROM AUTHOR]

Over 60% of all patients with dura mater graft-associated Creutzfeldt-Jakob disease (dCJD) have been diagnosed in Japan. The incubation period has ranged from 1 to 30 years and the age at onset from 15 to 80 years. Here, we report a 77-year-old male Japanese autopsied dCJD case with the longest incubation period so far in Japan. He received a cadaveric dural graft at the right cranial convexity following a craniotomy for meningioma at the age of 46. At 30 years post-dural graft placement, disorientation was observed as an initial symptom of dCJD. He rapidly began to present with inconsistent speech, cognitive impairment and tremor of the left upper extremity. Occasional myoclonic jerks were predominantly observed on the left side. Brain MRI presented hyperintense signals on diffusion-weighted and T2-weighted images, at the right cerebral cortex. The most hyperintense lesion was located at the right parietal lobe, where the dura mater graft had been transplanted. Single-photon emission CT scan showed markedly decreased cerebral blood flow at the right parietal lobe. EEG revealed diffuse and slow activities with periodic sharp-wave complex discharges seen in the right parietal, temporal and occipital lobes. He died of pneumonia 9 months after onset. Brain pathology revealed non-plaque-type dCJD. Laterality of neuropathological changes, including spongiform change, neuronal loss, gliosis or PrP deposits, was not evident. Western blot analysis showed type 1 PrPCJD. Alzheimer-type pathology and PSP-like pathology were also observed. [ABSTRACT FROM AUTHOR]

Cerebral venous thrombosis (CVT) has a broad spectrum of clinical presentation compared to arterial etiology. Seizure is one of the common symptoms and is more frequent than in other stroke types. Hence, transient neurological symptoms in CVT patients are usually due to epileptic seizures, while transient repetitive movement disorder is extremely rare except as a complication of epilepsy. We report a case of CVT in the superior sagittal sinus with a 1-year history of paroxysmal kinetic tremor without evident epilepsy. [ABSTRACT FROM AUTHOR]