Quantification of monoamine oxidase B expression with C-SL25.1188 for imaging reactive astrocytes in patients with Alzheimer's disease.

Purpose: Astrocyte reactivation can be assessed using positron emission tomography (PET) ligands targeting monoamine oxidase B (MAO-B). C-SL25.1188 binds reversibly to MAO-B, allowing precise density measurements, but requires invasive arterial sampling.

Neuropathological correlations of F-florzolotau PET in a case with pick's disease.

Background: Pick's disease (PiD) is classified as frontotemporal lobar degeneration with pathological tau aggregates. Positron emission tomography (PET) with F-florzolotau provides high-contrast imaging of diverse tau fibrils. While our previous work demonstrated the detectability of three repeat (3R) tau pathology by F-florzolotau PET in an autopsy-confirmed PiD patient, its potential for quantitative assessment of 3R tau aggregates in living individuals remains unclear.

Diverse tau pathologies in late-life mood disorders revealed by PET and autopsy assays.

Introduction: Late-life mood disorders (LLMDs) may represent prodromal manifestations of neurodegenerative dementia; however, the neuropathological basis of LLMDs, including depression and bipolar disorder, remains unclear. We aimed to investigate the involvement of Alzheimer's disease (AD) and non-AD tau pathologies in LLMD participants.

Methods: Fifty-two LLMD participants and 47 age- and sex-matched healthy controls (HCs) underwent tau and amyloid beta (Aβ) positron emission tomography (PET) imaging using F-florzolotau and C-Pittsburgh compound B.

Plasma biomarkers for early detection of alzheimer's disease: a cross-sectional study in a Japanese cohort.

Background: Plasma biomarkers offer a promising alternative to amyloid beta (Aβ) positron emission tomography (PET) or cerebrospinal fluid (CSF) biomarkers for diagnosing Alzheimer's disease (AD). This cross-sectional study assessed the utility of multiple plasma biomarkers for diagnosing and staging AD in a Japanese cohort.

Methods: The assessed plasma biomarkers included Aβ42/40, phosphorylated tau (p-tau181 and p-tau217), glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL), individually and in combination.

Diffusion Tensor Image Analysis Along the Perivascular Space in Former Professional Athletes with Repetitive Mild Traumatic Brain Injury History.

Rationale And Objectives: The long-term changes in the glymphatic system of former professional athletes exposed to repetitive mild traumatic brain injuries remain poorly understood. This study aimed to use diffusion tensor image analysis along the perivascular space (DTI-ALPS) to evaluate the glymphatic system activity and correlate the ALPS index with neuropsychiatric symptoms in former professional athletes.

Materials And Methods: 30 former professional athletes and 24 age- and sex-matched controls underwent DTI with 3 T magnetic resonance imaging, and neuropsychiatric tests were performed in the athlete group.

Identifying reversible psychiatric dementia mimics in new memory clinic outpatients.

Background: Timely identification of reversible conditions that mimic dementia is critical in memory clinic practice. However, psychiatric conditions as potential dementia mimics have not been studied as thoroughly as neurological ones, and detailed data on their reversibility remain limited.

Objective: To identify reversible psychiatric dementia mimics.

-Linked Parkinson Syndrome in Female Heterozygotes Is Associated With PET-Detectable Tau Pathology.

Background And Objectives: A previous postmortem study of men with Christianson syndrome, a disorder caused by loss-of-function mutations in the gene , reported a mechanistic link between pathologic tau accumulation and progressive symptoms such as cerebellar atrophy and cognitive decline. This study aimed to characterize the relationships between neuropathologic manifestations and tau accumulation in heterozygous women with mutation.

Methods: We conducted a multimodal neuroimaging and plasma biomarker study on 3 middle-aged heterozygous women with mutations (proband 1: mid-50s; proband 2: early 50s; proband 3: mid-40s) presenting with progressive extrapyramidal symptoms.

Can the clinical sign "head-turning sign" and simple questions in "Neucop-Q" predict amyloid β pathology?

Background: To establish simple screening tests to suspect Alzheimer's disease (AD) pathology, the clinical sign "head-turning sign" (HTS), which is a patient's behavior of turning their head towards their partner to seek assistance with questions posed by the examiner during the interview, and the simple screening questionnaire for dementia named "Neucop-Q" were validated in participants diagnosed with amyloid and tau positron emission tomography (PET).

Methods: We enrolled 155 patients: 47 cognitive normal, 36 with mild cognitive impairment, 64 with dementia, and 8 with psychiatric disorders. All participants underwent Neucop-Q [three questions: Consciousness/self-awareness of cognitive disabilities (C) normal/impaired (nor/imp), Pleasure/pastime (P) nor/imp, and News/knowledge on current topics (N) nor/imp] and amyloid/tau PET.

Alterations of striatal phosphodiesterase 10 A and their association with recurrence rate in bipolar I disorder.

Phosphodiesterase 10 A (PDE10A), a pivotal element of the second messenger signaling downstream of the dopamine receptor stimulation, is conceived to be crucially involved in the mood instability of bipolar I disorder (BD-I) as a primary causal factor or in response to dysregulated dopaminergic tone. We aimed to determine whether striatal PDE10A availability is altered in patients with BD-I and assessed its relationship with the clinical characteristics of BD-I. This case-control study used positron emission tomography (PET) with 2-(2-(3-(4-(2-[F]fluoroethoxy)phenyl)-7-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)ethyl)-4-isopropoxyisoindoline-1,3-dione ([F]MNI-659), a radioligand that binds to PDE10A, to examine the alterations of the striatal PDE10A availability in the living brains of individuals with BD-I and their association with the clinical characteristics of BD-I.

[Tau Positron Emission Tomography: Applications in Diagnosis and Prognosis of Various Diseases].

Tau positron emission tomography (PET) is a neuroimaging technique that visualizes tau deposition using PET tracers that selectively bind to tau aggregates. Studies have reported the diagnostic and prognostic value of tau PET in Alzheimer's disease and other tauopathies. However, the binding profiles of tau PET drugs vary widely across tauopathies; therefore, an accurate understanding of the disease-specific characteristics is essential for interpretation of tau PET findings.

Late-life mood disorder as the initial presentation of progressive supranuclear palsy: A case series.

Aim: Progressive supranuclear palsy (PSP) is a rapidly progressive neurodegenerative disorder characterized by Parkinsonism, supranuclear ophthalmoplegia, postural instability, and cognitive impairment.

Patients: This case series describes three patients initially diagnosed with late-life mood disorders (depression and bipolar disorder) who were later diagnosed with PSP because of the development of typical neurological symptoms.

Result: The diagnostic challenge of PSP is highlighted in this case report, particularly in the early stages, when characteristic symptoms may not be present.

Investigating the Link Between Subjective Depth Perception Deficits and Objective Stereoscopic Vision Deficits in Individuals With Acquired Brain Injury.

Individuals with acquired brain injury have reported subjective complaints of depth perception deficits, but few have undergone objective assessments to confirm these deficits. As a result, the literature currently lacks reports detailing the correlation between subjective depth perception deficits and objective stereoscopic vision deficits in individuals with acquired brain injury, particularly those cases that are characterized by a clearly defined lesion. To investigate this relationship, we recruited three individuals with acquired brain injury who experienced depth perception deficits and related difficulties in their daily lives.

Association between mammillary body atrophy and memory impairment in retired athletes with a history of repetitive mild traumatic brain injury.

Cognitive dysfunction, especially memory impairment, is a typical clinical feature of long-term symptoms caused by repetitive mild traumatic brain injury (rmTBI). The current study aims to investigate the relationship between regional brain atrophy and cognitive impairments in retired athletes with a long history of rmTBI. Overall, 27 retired athletes with a history of rmTBI (18 boxers, 3 kickboxers, 2 wrestlers, and 4 others; rmTBI group) and 23 age/sex-matched healthy participants (control group) were enrolled.

PET classification of tau pathologies in patients with frontotemporal dementia.

Frontotemporal dementia refers to a group of neurodegenerative disorders with diverse clinical and neuropathological features. neuropathological assessments of frontotemporal dementia at an individual level have hitherto not been successful. In this study, we aim to classify patients with frontotemporal dementia based on topologies of tau protein aggregates captured by PET with F-florzolotau (aka F-APN-1607 and F-PM-PBB3), which allows high-contrast imaging of diverse tau fibrils in Alzheimer's disease as well as in non-Alzheimer's disease tauopathies.

Spontaneous Bladder Rupture in a Catatonic Schizophrenia Patient.

Catatonia is a psychiatric emergency in schizophrenia that often leads to excessive activation of the sympathetic nervous system. Urinary retention in catatonia is often underestimated but has potentially detrimental consequences. Herein, we present the case of a woman in her 40s with schizophrenia treated for catatonia during a relapse.

Performance of plasma Aβ42/40, measured using a fully automated immunoassay, across a broad patient population in identifying amyloid status.

Background: Plasma biomarkers have emerged as promising screening tools for Alzheimer's disease (AD) because of their potential to detect amyloid β (Aβ) accumulation in the brain. One such candidate is the plasma Aβ42/40 ratio (Aβ42/40). Unlike previous research that used traditional immunoassay, recent studies that measured plasma Aβ42/40 using fully automated platforms reported promising results.

Association of protein distribution and gene expression revealed by positron emission tomography and postmortem gene expression in the dopaminergic system of the human brain.

Purpose: The topological distribution of dopamine-related proteins is determined by gene transcription and subsequent regulations. Recent research strategies integrating positron emission tomography with a transcriptome atlas have opened new opportunities to understand the influence of regulation after transcription on protein distribution. Previous studies have reported that messenger (m)-RNA expression levels spatially correlate with the density maps of serotonin receptors but not with those of transporters.

Shadowing Behavior May Be Associated with an Inability to Recognize the External World: A Case Report of Shadowing in a Patient with Posterior Cortical Atrophy.

Although shadowing behavior- when one individual closely follows another- is routinely documented among patients with dementia, its mechanisms have yet to be elucidated. In particular, there have been no detailed descriptions of patients with shadowing behavior. To propose its potential backgrounds, we describe a patient with posterior cortical atrophy who exhibited prominent shadowing behavior.

Pneumonia Risk Increased by Dementia-Related Daily Living Difficulties: Poor Oral Hygiene and Dysphagia as Contributing Factors.

Objective: Although pneumonia is the leading cause of death among patients with dementia, the specific underlying causes remain unclear. In particular, the potential connection between pneumonia risk and dementia-related daily living difficulties, such as oral hygiene practice and mobility impairment, and the use of physical restraint as a management practice, has not been extensively studied.

Methods: In our retrospective study, we included 454 admissions corresponding to 336 individual patients with dementia who were admitted to a neuropsychiatric unit due to behavioral and psychological symptoms.

Intravenous pulse methylprednisolone and corticosteroid-induced psychiatric disorders: A retrospective study.

Objective: Corticosteroids can cause psychiatric symptoms known as corticosteroid-induced psychiatric disorders (CIPDs). Little is known regarding the relationship between intravenous pulse methylprednisolone (IVMP) and CIPDs. Therefore, we aimed to examine the relationship between corticosteroid use and CIPDs in this retrospective study.

Positron Emission Tomography Assessments of Phosphodiesterase 10A in Patients With Schizophrenia.

Background And Hypothesis: Phosphodiesterase 10A (PDE10A) is a highly expressed enzyme in the basal ganglia, where cortical glutamatergic and midbrain dopaminergic inputs are integrated. Therapeutic PDE10A inhibition effects on schizophrenia have been reported previously, but the status of this molecule in the living patients with schizophrenia remains elusive. Therefore, this study aimed to investigate the central PDE10A status in patients with schizophrenia and examine its relationship with psychopathology, cognition, and corticostriatal glutamate levels.

An optimized reference tissue method for quantification of tau protein depositions in diverse neurodegenerative disorders by PET with F-PM-PBB3 (F-APN-1607).

Positron emission tomography (PET) with F-PM-PBB3 (F-APN-1607, F-Florzolotau) enables high-contrast detection of tau depositions in various neurodegenerative dementias, including Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). A simplified method for quantifying radioligand binding in target regions is to employ the cerebellum as a reference (CB-ref) on the assumption that the cerebellum has minimal tau pathologies. This procedure is typically valid in AD, while FTLD disorders exemplified by progressive supranuclear palsy (PSP) are characterized by occasional tau accumulations in the cerebellum, hampering the application of CB-ref.

A Machine Learning-Based Approach to Discrimination of Tauopathies Using [ F]PM-PBB3 PET Images.

Background: We recently developed a positron emission tomography (PET) probe, [ F]PM-PBB3, to detect tau lesions in diverse tauopathies, including mixed three-repeat and four-repeat (3R + 4R) tau fibrils in Alzheimer's disease (AD) and 4R tau aggregates in progressive supranuclear palsy (PSP). For wider availability of this technology for clinical settings, bias-free quantitative evaluation of tau images without a priori disease information is needed.

Objective: We aimed to establish tau PET pathology indices to characterize PSP and AD using a machine learning approach and test their validity and tracer capabilities.