Peripheral immune profile in drug-naïve dementia with Lewy bodies.

BACKGROUND: Accumulating evidence suggests that peripheral inflammation is associated with the pathogenesis of Parkinson's disease (PD). We examined peripheral immune profiles and their association with clinical characteristics in patients with DLB and compared these with values in patients with PD. METHODS: We analyzed peripheral blood from 93 participants (drug-naïve DLB, 31; drug-naïve PD, 31; controls, 31). Absolute leukocyte counts, absolute counts of leukocyte subpopulations, and peripheral blood inflammatory indices such as neutrophil-to-lymphocyte ratio were examined. Associations with clinical characteristics, cardiac sympathetic denervation, and striatal 123I-2-carbomethoxy-3-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) binding were also examined. RESULTS: Patients with DLB had lower absolute lymphocyte and basophil counts than did age-matched controls (both; p < 0.005). Higher basophil counts were marginally associated with higher global cognition (p = 0.054) and were significantly associated with milder motor severity (p = 0.020) and higher striatal 123I-FP-CIT binding (p = 0.038). By contrast, higher basophil counts were associated with more advanced PD characterized by decreased global cognition and severe cardiac sympathetic denervation. Although lower lymphocyte counts had relevance to more advanced PD, they had little relevance to clinical characteristics in patients with DLB. Higher peripheral blood inflammatory indices were associated with lower body mass index in both DLB and PD. CONCLUSIONS: As in patients with PD, the peripheral immune profile is altered in patients with DLB. Some peripheral immune cell counts and inflammatory indices reflect the degree of disease progression. These findings may deepen our knowledge on the role of peripheral inflammation in the pathogenesis of DLB.

Clinicopathological study of dementia with grains presenting with parkinsonism compared with a typical case.

Argyrophilic grain disease (AGD) is one of the major pathological backgrounds of senile dementia. Dementia with grains refers to cases of dementia for which AGD is the sole background pathology responsible for dementia. Recent studies have suggested an association between dementia with grains and parkinsonism. In this study, we aimed to present two autopsy cases of dementia with grains. Case 1 was an 85-year-old man who exhibited amnestic dementia and parkinsonism, including postural instability, upward gaze palsy, and neck and trunk rigidity. The patient was clinically diagnosed with progressive supranuclear palsy and Alzheimer's disease. Case 2 was a 90-year-old man with pure amnestic dementia, clinically diagnosed as Alzheimer's disease. Recently, we used cryo-electron microscopy to confirm that the tau accumulated in both cases had the same three-dimensional structure. In this study, we compared the detailed clinical picture and neuropathological findings using classical staining and immunostaining methods. Both cases exhibited argyrophilic grains and tau-immunoreactive structures in the brainstem and basal ganglia, especially in the nigrostriatal and limbic systems. However, Case 1 had more tau immunoreactive structures. Considering the absence of other disease-specific structures such as tufted astrocytes, astrocytic plaques and globular glial inclusions, lack of conspicuous cerebrovascular disease, and no history of medications that could cause parkinsonism, our findings suggest an association between AGD in the nigrostriatal system and parkinsonism.

Impact of Istradefylline on Levodopa Dose Escalation in Parkinson's Disease: ISTRA ADJUST PD Study, a Multicenter, Open-Label, Randomized, Parallel-Group Controlled Study.

INTRODUCTION: A higher levodopa dose is a risk factor for motor complications in Parkinson's disease (PD). Istradefylline (IST) is used as adjunctive treatment to levodopa in PD patients with off episodes, but its impact on levodopa dose titration remains unclear. The objective of this study was to investigate the effect of IST on levodopa dose escalation in PD patients with wearing-off. METHODS: This was a multicenter, open-label, randomized, parallel-group controlled study (ISTRA ADJUST PD) in which PD patients experiencing wearing-off (n = 114) who were receiving levodopa 300-400 mg/day were randomized to receive IST or no IST (control). Levodopa dose was escalated according to clinical severity. The primary endpoint was cumulative additional levodopa dose, and secondary endpoints were changes in symptom rating scales, motor activity determined by a wearable device, and safety outcomes. RESULTS: The cumulative additional levodopa dose throughout 37 weeks and dose increase over 36 weeks were significantly lower in the IST group than in the control group (both p < 0.0001). The Movement Disorder Society Unified Parkinson's Disease Rating Scale Part I and device-evaluated motor activities improved significantly from baseline to 36 weeks in the IST group only (all p < 0.05). Other secondary endpoints were comparable between the groups. Adverse drug reactions (ADRs) occurred in 28.8% and 13.2% of patients in the IST and control groups, respectively, with no serious ADRs in either group. CONCLUSION: IST treatment reduced levodopa dose escalation in PD patients, resulting in less cumulative levodopa use. Adjunctive IST may improve motor function more objectively than increased levodopa dose in patients with PD. TRIAL REGISTRATION: Japan Registry of Clinical Trials: jRCTs031180248.

Multimodal treatment, including extracorporeal shock wave therapy, for refractory chronic tension-type headache: a case report.

BACKGROUND: Few reports have described multidisciplinary treatment, including extracorporeal shock wave therapy, for patients with refractory chronic tension-type headache. In this study, we conducted multidisciplinary treatment for a patient with chronic tension-type headache who suffered from chronic headache refractory to treatment. CASE PRESENTATION: The patient was a 45-year-old Japanese male suffering from 20 years of headache. As his headache had worsened recently, he visited a local clinic. With the diagnosis of suspected tension-type headache, its treatment was unsuccessful and he was referred to our hospital. The neurology department confirmed the tension-type headache and prescribed another medication, but he showed no improvement. Then, the patient was referred to the rehabilitation medicine department for consultation. At the initial visit, we identified multiple myofascial trigger points in his bilateral posterior neck and upper back regions. At the initial visit, he was prescribed 10 mL of 1% lidocaine injected into the muscles in these areas. In addition, he received 2000 extracorporeal shock wave therapy into bilateral trapezius muscles, and was instructed to take oral Kakkonto extract granules, benfotiamine, pyridoxine hydrochloride, and cyanocobalamin. Cervical muscle and shoulder girdle stretches and exercises were also recommended. At follow-up treatment visits, we used extracorporeal shock wave therapy to bilateral trapezius muscles, which led to immediate pain relief. After 11 weeks, he was not taking any medication and his headache was subjectively improved and his medical treatment ended. CONCLUSION: A patient with chronic tension-type headache refractory to regular treatment was successfully treated with a multimodal approach including extracorporeal shock wave therapy in addition to standard treatment. For patients with tension-type headache accompanied by myofascial trigger points, it may be recommended to promptly consider aggressive multimodal treatment that includes extracorporeal shock wave therapy.

Morphological study of the phrenic nerve to determine a reference value for the myelinated fiber density in elderly individuals.

Phrenic nerves (PNs) play an important role in respiration; however, very few morphological studies have assessed them. This study aimed to provide control reference values, including the density of large and small myelinated PN fibers, for future pathological studies. We assessed a total of nine nerves from eight cases among consecutive autopsy cases registered to the Brain Bank for Aging Research between 2018 and 2019 (five men and three women, mean age 77.0 ± 7.0 years). The nerves were sampled distally, and their structures were analyzed using semi-thin sections stained with toluidine blue. The mean and standard deviation of the density of each myelinated fiber of the PN was 6908 ± 1132 fibers/mm2 (total myelinated fiber), 4095 ± 586 fibers/mm2 (large diameter myelinated fiber; diameter ≥7 µm), and 2813 ± 629 fibers/mm2 (small diameter myelinated fiber; diameter <7 µm). There was no correlation between myelinated fiber density and age. This study provides the density measurement of the human PN myelinated fiber, and these findings can be used as reference values for the PN in elderly individuals.

CSF P-Tau181 and Other Biomarkers in Patients With Neuronal Intranuclear Inclusion Disease.

BACKGROUND AND OBJECTIVES: CSF tau phosphorylated at threonine 181 (p-tau181) is a widely used biomarker for Alzheimer disease (AD) and has recently been regarded to reflect ß-amyloid and/or p-tau deposition in the AD brain. Neuronal intranuclear inclusion disease (NIID) is a neurodegenerative disease characterized by intranuclear inclusions in neurons, glial cells, and other somatic cells. Symptoms include dementia, neuropathy, and others. CSF biomarkers were not reported. The objective of this study was to investigate whether CSF biomarkers including p-tau181 are altered in patients with NIID. METHODS: This was a retrospective observational study. CSF concentrations of p-tau181, total tau, amyloid-beta 1-42 (Aß42), monoamine metabolites homovanillic acid (HVA), and 5-hydroxyindole acetic acid (5-HIAA) were compared between 12 patients with NIID, 120 patients with Alzheimer clinical syndrome biologically confirmed based on CSF biomarker profiles, and patients clinically diagnosed with other neurocognitive disorders (dementia with Lewy bodies [DLB], 24; frontotemporal dementia [FTD], 13; progressive supranuclear palsy [PSP], 21; and corticobasal syndrome [CBS], 13). Amyloid PET using Pittsburgh compound B (PiB) was performed in 6 patients with NIID. RESULTS: The mean age of patients with NIID, AD, DLB, FTD, PSP, and CBS was 71.3, 74.6, 76.8, 70.2, 75.5, and 71.9 years, respectively. CSF p-tau181 was significantly higher in NIID (72.7 ± 24.8 pg/mL) compared with DLB, PSP, and CBS and was comparable between NIID and AD. CSF p-tau181 was above the cutoff value (50.0 pg/mL) in 11 of 12 patients with NIID (91.7%). Within these patients, only 2 patients showed decreased CSF Aß42, and these patients showed negative or mild local accumulation in PiB PET, respectively. PiB PET scans were negative in the remaining 4 patients tested. The proportion of patients with increased CSF p-tau181 and normal Aß42 (A-T+) was significantly higher in NIID (75%) compared with DLB, PSP, and CBS (4.2%, 4.8%, and 7.7%, respectively). CSF HVA and 5-HIAA concentrations were significantly higher in patients with NIID compared with disease controls. DISCUSSION: CSF p-tau181 was increased in patients with NIID without amyloid accumulation. Although the deposition of p-tau has not been reported in NIID brains, the molecular mechanism of tau phosphorylation or secretion of p-tau may be altered in NIID.

Autopsy Validation of the Diagnostic Accuracy of 123I-Metaiodobenzylguanidine Myocardial Scintigraphy for Lewy Body Disease.

BACKGROUND AND OBJECTIVES: 123I-meta-iodobenzyl-guanidine (123I-MIBG) myocardial scintigraphy is used as a diagnostic imaging test to differentiate Lewy body diseases (LBDs), including Parkinson disease and dementia with Lewy bodies, from other similar diseases. However, this imaging test lacks validation of its diagnostic accuracy against the gold standard. Our aim was to validate the diagnostic accuracy of 123I-MIBG myocardial scintigraphy for LBD against autopsy, the gold standard. METHODS: This retrospective, cross-sectional study included consecutive autopsy patients from the Brain Bank for Aging Research who had undergone 123I-MIBG myocardial scintigraphy. We compared the 123I-MIBG myocardial scintigraphy findings with autopsy findings. Furthermore, the proportion of residual tyrosine hydroxylase (TH)-immunoreactive sympathetic fibers in the anterior wall of the left ventricle was investigated to assess the condition of the cardiac sympathetic nerves assumed to cause reduced 123I-MIBG uptake in LBDs. RESULTS: We analyzed the data of 56 patients (30 with pathologically confirmed LBDs and 26 without LBD pathology). Compared with the neuropathologic diagnosis, the early heart-to-mediastinum (H/M) ratio had a sensitivity and specificity of 70.0% (95% CI 50.6%-85.3%) and 96.2% (95% CI 80.4%-99.9%), respectively. The delayed H/M ratio had a sensitivity and specificity of 80.0% (95% CI 61.4%-92.3%) and 92.3% (95% CI 74.9%-99.1%), respectively. The washout rate had a sensitivity and specificity of 80.0% (95% CI 61.4%-92.3%) and 84.6% (95% CI 65.1%-95.6%), respectively. The proportion of residual TH-immunoreactive cardiac sympathetic fibers strongly correlated with the amount of cardiac 123I-MIBG uptake when assessed with early and delayed H/M ratio values (correlation coefficient 0.75 and 0.81, respectively; p < 0.001). DISCUSSION: This clinicopathologic validation study revealed that 123I-MIBG myocardial scintigraphy could robustly differentiate LBDs from similar diseases. Abnormal 123I-MIBG myocardial scintigraphy findings strongly support the presence of LBD and cardiac sympathetic denervation. However, LBD pathology should not necessarily be excluded by normal myocardial scintigraphy results, especially when other biomarkers suggest the presence of comorbid Alzheimer disease pathology. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that 123I-MIBG myocardial scintigraphy accurately identifies patients with LBD.

Evaluating the impact of adjunctive istradefylline on the cumulative dose of levodopa-containing medications in Parkinson's disease: study protocol for the ISTRA ADJUST PD randomized, controlled study.

BACKGROUND: Levodopa remains the most effective symptomatic treatment for Parkinson's disease (PD) more than 50 years after its clinical introduction. However, the onset of motor complications can limit pharmacological intervention with levodopa, which can be a challenge when treating PD patients. Clinical data suggest using the lowest possible levodopa dose to balance the risk/benefit. Istradefylline, an adenosine A2A receptor antagonist indicated as an adjunctive treatment to levodopa-containing preparations in PD patients experiencing wearing off, is currently available in Japan and the US. Preclinical and preliminary clinical data suggested that adjunctive istradefylline may provide sustained antiparkinsonian benefits without a levodopa dose increase; however, available data on the impact of istradefylline on levodopa dose titration are limited. The ISTRA ADJUST PD study will evaluate the effect of adjunctive istradefylline on levodopa dosage titration in PD patients. METHODS: This 37-week, multicenter, randomized, open-label, parallel-group controlled study in PD patients aged 30-84 years who are experiencing the wearing-off phenomenon despite receiving levodopa-containing medications ≥ 3 times daily (daily dose 300-400 mg) began in February 2019 and will continue until February 2022. Enrollment is planned to attain 100 evaluable patients for the efficacy analyses. Patients will receive adjunctive istradefylline (20 mg/day, increasing to 40 mg/day) or the control in a 1:1 ratio, stratified by age, levodopa equivalent dose, and presence/absence of dyskinesia. During the study, the levodopa dose will be increased according to symptom severity. The primary study endpoint is the comparison of the cumulative additional dose of levodopa-containing medications during the treatment period between the adjunctive istradefylline and control groups. Secondary endpoints include changes in efficacy rating scales and safety outcomes. DISCUSSION: This study aims to clarify whether adjunctive istradefylline can reduce the cumulative additional dose of levodopa-containing medications in PD patients experiencing the wearing-off phenomenon, and lower the risk of levodopa-associated complications. It is anticipated that data from ISTRA ADJUST PD will help inform future clinical decision-making for patients with PD in the real-world setting. TRIAL REGISTRATION: Japan Registry of Clinical Trials, jRCTs031180248 ; registered 12 March 2019.

Rasagiline does not exacerbate autonomic blood pressure dysregulation in early or mild Parkinson's disease.

INTRODUCTION: Orthostatic hypotension (OH) and abnormal blood pressure (BP) fluctuations occur mainly due to noradrenergic dysfunction and are clinically important in patients with Parkinson's disease (PD). They lead to impairments of cognition function, daily activities, and quality of life. Some monoamine oxidase (MAO)-B inhibitors have a sympathomimetic amine, which can be attributed to OH. Therefore, we determined whether rasagiline, a common MAO-B inhibitor used in PD treatment, can contribute to cardiovascular autonomic BP dysregulation in patients with early or mild PD. METHODS: Nineteen patients with early or mild PD were recruited, and tilt test and 24-h ambulatory BP monitoring (ABPM) were performed before and after rasagiline administration. Early or mild PD was defined as patients with de novo (n = 4), levodopa (n = 10), dopamine agonist (n = 1), levodopa and one dopamine agonist (n = 2), levodopa and droxidopa (n = 1), and levodopa and istradefylline (n = 1). Furthermore, patients with motor fluctuation and multiple dopamine agonists were excluded from our study. RESULTS: OH and BP frequency were not significantly exacerbated before or after rasagiline administration. No significant differences of type in BP fluctuation on ABPM and the degree of nocturnal BP falls were found before and after rasagiline administration. The Unified Parkinson's Disease Rating Scale motor score in patients (post-rasagiline administration) was significantly improved compared with before. CONCLUSION: Rasagiline seems to be a suitable medication for Parkinsonian symptoms in patients with early and mild PD. It does not exacerbate cardiovascular autonomic responses, circadian rhythm of BP, or both.

Parkinson's disease with a typical clinical course of 17 years overlapped by Creutzfeldt-Jakob disease: an autopsy case report.

BACKGROUND: Late-stage Parkinson's disease (PD) often presents with neuropsychiatric symptoms such as dementia, psychosis, excessive daytime sleepiness, apathy, depression, and anxiety. However, neuropsychiatric symptoms are the cardinal features of Creutzfeldt-Jakob disease (CJD), raising the possibility that CJD may be an overlooked condition when it accompanies late-stage PD. CASE PRESENTATION: We describe a female autopsy case of PD with a typical clinical course of 17 years, in which CJD overlapped with PD during the final year of the patient's life. The patient died aged 85 years. Neuropathological features included widespread Lewy body-related α-synucleinopathy predominantly in the brainstem and limbic system, as well as the typical pathology of methionine/methionine type 1 CJD in the brain. CONCLUSIONS: Our case demonstrates the clinicopathological co-occurrence of PD and CJD in a sporadic patient. The possibility of mixed pathology, including prion pathology, should be taken into account when neuropsychiatric symptoms are noted during the disease course of PD.

Lewy pathology of the submandibular gland in Lewy body disease: A report of autopsy cases.

Accumulation of phosphorylated α-synuclein in the central and peripheral nervous systems is a histological hallmark of Lewy body disease (LBD), including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and LB-related pure autonomic failure. The submandibular gland is employed as a biopsy site for detecting Lewy pathology; however, the incidence of Lewy pathology in this region in autopsy-proven LBD cases at all stages from an aged Japanese cohort remains unclear. To validate the utility of Lewy pathology of the submandibular gland as a diagnostic biomarker for LBD, we investigated the submandibular gland Lewy pathology in autopsied patients. To determine the specificity, we prospectively evaluated the submandibular gland in 64 consecutive autopsied patients. To determine the sensitivity, we retrospectively assessed the submandibular gland in 168 consecutive autopsied patients who had prodromal or clinical LBD. In the prospective study, Lewy pathology was found in 21 of 64 patients, and nine of those 21 patients had the submandibular gland Lewy pathology. No Lewy pathology was found in 43 patients without CNS Lewy pathology, giving a specificity of 100%. In the retrospective study, Lewy pathology of the submandibular gland was detected in 126 of 168 patients. The sensitivity was 89.1% in PD and 75.4% in DLB. The sensitivity increased with disease progression. These findings support the utility of the submandibular gland biopsy for the pathological diagnosis of LBD.

Frontal lobe dysfunction is associated with reduced DAT-SPECT accumulation in Lewy body disease.

INTRODUCTION: Lewy body disease (LBD) causes olfactory or cognitive dysfunction even before motor symptoms emerge. Recent reports indicate that the dopamine transporter (DAT), which can be imaged using single-photon emission computed tomography (123I-ioflupane SPECT), is related to olfactory and cognitive dysfunction in LBD patients. We suspected that decreased cerebral blood flow (CBF) in the frontal lobe might be involved in these relationships. If so, then the results of these examinations may be useful in assessing the pathological progression of Lewy bodies. METHODS: We retrospectively analyzed the data of 139 de novo consecutive patients with LBD. We used the Odor Stick Identification Test for Japanese (OSIT-J) and the Frontal Assessment Battery (FAB) to evaluate olfactory and frontal lobe dysfunction, respectively. Among the 139 patients, ultimately 84 patients were analyzed and underwent 123I-ioflupane SPECT within 3 months (before or after) of the OSIT-J and FAB. We categorized patients on the basis of whether frontal lobe CBF was reduced (n = 28) or normal (n = 56). RESULTS: The average OSIT-J and FAB scores were 4.0 and 14.1, respectively, and the scores on the two tests were significantly correlated. Furthermore, OSIT-J scores were significantly correlated with the specific binding ratio (SBR) in both groups. The SBR was correlated with FAB scores in patients with reduced CBF in the frontal lobe, but not in those with normal CBF. CONCLUSION: Frontal lobe dysfunction and striatum dysfunction are correlated in LBD patients only after CBF has declined. Also, there is a time lag in the appearance of olfactory dysfunction and frontal lobe dysfunction in LBD patients. As with pathological development, olfaction is impaired earliest, followed by striatal, and then frontal lobe dysfunction.

Association between heart rate variability and striatal dopamine depletion in Parkinson's disease.

Striatal dopamine depletion is associated with not only motor symptom but also non-motor symptoms in patients with Parkinson's disease (PD). The purpose is to elucidate the relation between heart rate variability (HRV) and dopaminergic depletion in specific striatal subregions. The subjects were 84 patients with newly diagnosed untreated PD. All patients underwent striatal 123I-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) dopamine transporter single-photon emission computed tomography (DAT-SPECT). DaTQUANT software (GE Healthcare) was used as a semi-quantitative tool to analyze DAT-SPECT data. Association of HRV with dopaminergic depletion in specific striatal subregions was examined. HRV was related to dopamine depletion in the caudate and anterior putamen, especially the left side, after controlling for age, hemoglobin A1c level, disease duration, motor severity and global cognition on multiple regression analysis (left caudate p = 0.012). HRV was closely related to striatal dopamine depletion, especially in the left associative striatum, in patients with PD.

Lewy pathology of the esophagus correlates with the progression of Lewy body disease: a Japanese cohort study of autopsy cases.

Lewy body disease (LBD) is a spectrum of progressive neurodegenerative disorders characterized by the wide distribution of Lewy bodies and neurites in the central and peripheral nervous system (CNS, PNS). Clinical diagnoses include Parkinson's disease (PD), dementia with Lewy bodies, or pure autonomic failure. All types of LBD are accompanied by non-motor symptoms (NMSs) including gastrointestinal dysfunctions such as constipation. Its relationship to Lewy body-related α-synucleinopathy (Lewy pathology) of the enteric nervous system (ENS) is attracting attention because it can precede the motor symptoms. To clarify the role of ENS Lewy pathology in disease progression, we performed a clinicopathological study using the Brain Bank for Aging Research in Japan. Five-hundred and eighteen cases were enrolled in the study. Lewy pathology of the CNS and PNS, including the lower esophagus as a representative of the ENS, was examined via autopsy findings. Results showed that one-third of older people (178 cases, 34%) exhibited Lewy pathology, of which 78 cases (43.8%) exhibited the pathology in the esophagus. In the esophageal wall, Auerbach's plexus (41.6%) was most susceptible to the pathology, followed by the adventitia (33.1%) and Meissner's plexus (14.6%). Lewy pathology of the esophagus was significantly associated with autonomic failures such as constipation (p < 0.0001) and among PNS regions, correlated the most with LBD progression (r = 0.95, p < 0.05). These findings suggest that the propagation of esophageal Lewy pathology is a predictive factor of LBD.

Metabolic Network Topology of Alzheimer's Disease and Dementia with Lewy Bodies Generated Using Fluorodeoxyglucose Positron Emission Tomography.

BACKGROUND: Alzheimer's disease (AD) and dementia with Lewy bodies (DLB) are often misdiagnosed with each other because of similar symptoms including progressive memory loss. The metabolic network topology that describes inter-regional metabolic connections can be generated using fluorodeoxyglucose positron emission tomography (FDG-PET) data with the graph-theoretical method. We hypothesized that different metabolic connectivity underlies the symptoms of AD patients, DLB patients, and cognitively normal (CN) individuals. OBJECTIVE: This study aimed to generate metabolic connectivity using FDG-PET data and assess the network topology to differentiate AD patients, DLB patients, and CN individuals. METHODS: This study included 45 AD patients, 18 DLB patients, and 142 CN controls. We analyzed FDG-PET data using the graph-theoretical method and generated the network topology in AD patients, DLB patients, and CN individuals. We statistically assessed the topology with global and nodal parameters. RESULTS: The whole metabolic network was preserved in CN; however, diffusely decreased connection was found in AD and partially but more deeply decreased connection was observed in DLB. The metabolic topology revealed that the right posterior cingulate and the left transverse temporal gyrus were significantly different between AD and DLB. CONCLUSION: The present findings indicate that metabolic connectivity decreased in both AD and DLB, compared with CN. DLB was characterized restricted but deeper stereotyped network disruption compared with AD. The right posterior cingulate and the left transverse temporal gyrus are significant regions in the metabolic connectivity for differentiating AD from DLB.

Aging and Alzheimer's disease pathology.

The number of people with dementia worldwide is predicted to increase to 131.5 million by 2050. When studying dementia, understanding the basis of the neuropathological background is very important. Taking Alzheimer's disease (AD) neuropathology as an example, we know that the accumulation of abnormal structures such as senile plaques and neurofibrillary tangles is a hallmark. Macroscopic atrophy affects the entorhinal area and hippocampus, amygdala, and associative regions of the neocortex. Braak advocates the spread of tau deposits from the entorhinal to associative regions of the neocortex as the disease progresses. If the AD has only tau pathology, the degree and distribution of tau deposition may be associated with clinical symptoms. However, AD is also accompanied by amyloid-ß deposition and even atrophy. Although it is possible to make a neuropathological diagnosis of AD from the spread of amyloid and tau depositions, neuropathological abnormal protein accumulation cannot explain all clinical symptoms of AD. There is an ambiguity between clinical symptoms and neuropathological findings. It is important to understand neuropathological findings while understanding that this ambiguity exists. So, for the reader's help, first we briefly explain the changes in the brain with age, and then describe AD as a typical disease of dementia; finally we will describe the diseases that mimic AD for neurologists who are not experts in neuropathology.

Monoamine Oxidase B Binding of 18F-THK5351 to Visualize Glioblastoma and Associated Gliosis: An Autopsy-Confirmed Case.

An 86-year-old woman with cognitive impairment and left hemiparesis underwent F-THK5351 PET 4 months before her death. In addition to "normal" off-target binding in the basal ganglia, abnormal accumulation was observed along the pyramidal tract and around the right basal ganglia as ring-shaped uptake that overlapped a gadolinium-enhanced lesion. Postmortem pathological examination revealed that she had glioblastoma multiforme with associated gliosis, in which monoamine oxidase B (MAO-B) activity is increased. In vitro autoradiography of the corresponding lesion demonstrated specific binding of F-THK5351, which was blocked by an MAO-B-selective ligand. Thus, F-THK5351 PET may reflect glioblastomas and associated gliosis by binding to MAO-B.