Peripheral innate immunophenotype in neurodegenerative disease: blood-based profiles and links to survival.

The innate immune system plays an integral role in the progression of many neurodegenerative diseases. In addition to central innate immune cells (e.g.

Blood inflammation relates to neuroinflammation and survival in frontotemporal lobar degeneration.

Neuroinflammation is an important pathogenic mechanism in many neurodegenerative diseases, including those caused by frontotemporal lobar degeneration (FTLD). Postmortem and in vivo imaging studies have shown brain inflammation early in these conditions, proportionate to symptom severity and rate of progression. However, evidence for corresponding blood markers of inflammation and their relationship with central inflammation and clinical outcome are limited.

Synaptic density affects clinical severity via network dysfunction in syndromes associated with frontotemporal lobar degeneration.

There is extensive synaptic loss from frontotemporal lobar degeneration, in preclinical models and human in vivo and post mortem studies. Understanding the consequences of synaptic loss for network function is important to support translational models and guide future therapeutic strategies. To examine this relationship, we recruited 55 participants with syndromes associated with frontotemporal lobar degeneration and 24 healthy controls.

Longitudinal Synaptic Loss in Primary Tauopathies: An In Vivo [ C]UCB-J Positron Emission Tomography Study.

Background: Synaptic loss is characteristic of many neurodegenerative diseases; it occurs early and is strongly related to functional deficits.

Objective: In this longitudinal observational study, we determine the rate at which synaptic density is reduced in the primary tauopathies of progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), and we test the relationship with disease progression.

Methods: Our cross-sectional cohort included 32 participants with probable PSP and 16 with probable CBD (all amyloid-negative corticobasal syndrome), recruited from tertiary care centers in the United Kingdom, and 33 sex- and age-matched healthy control subjects.

Role of adenosine A2A receptors in hot and cold cognition: Effects of single-dose istradefylline in healthy volunteers.

The role of the adenosine neurochemical system in human cognition is under-studied, despite such receptors being distributed throughout the brain. The aim of this study was to shed light on the role of the adenosine A2A receptors in human cognition using single-dose istradefylline. Twenty healthy male participants, aged 19-49, received 20 mg istradefylline and placebo, in a randomized, double-blind, placebo-controlled cross-over design.

Chronic escitalopram in healthy volunteers has specific effects on reinforcement sensitivity: a double-blind, placebo-controlled semi-randomised study.

Several studies of the effects on cognition of selective serotonin reuptake inhibitors (SSRI), administered either acutely or sub-chronically in healthy volunteers, have found changes in learning and reinforcement outcomes. In contrast, to our knowledge, there have been no studies of chronic effects of escitalopram on cognition in healthy volunteers. This is important in view of its clinical use in major depressive disorder (MDD) and obsessive-compulsive disorder (OCD).

Synaptic Loss in Frontotemporal Dementia Revealed by [ C]UCB-J Positron Emission Tomography.

Objective: Synaptic loss is an early feature of neurodegenerative disease models, and is severe in post mortem clinical studies, including frontotemporal dementia. Positron emission tomography (PET) with radiotracers that bind to synaptic vesicle glycoprotein 2A enables quantification of synaptic density in vivo. This study used [ C]UCB-J PET in participants with behavioral variant frontotemporal dementia (bvFTD), testing the hypothesis that synaptic loss is severe and related to clinical severity.

Morphometric similarity deviations in stimulant use disorder point towards abnormal brain ageing.

Chronic drug use negatively impacts ageing, resulting in diminished health and quality of life. However, little is known about biomarkers of abnormal ageing in stimulant drug users. Using morphometric similarity network mapping, a novel approach to structural connectomics, we first mapped cross-sectional morphometric similarity trajectories of ageing in the publicly available Rockland Sample (20-80 years of age,  = 665).

Differential levels of plasma biomarkers of neurodegeneration in Lewy body dementia, Alzheimer's disease, frontotemporal dementia and progressive supranuclear palsy.

Objectives: This longitudinal study compared emerging plasma biomarkers for neurodegenerative disease between controls, patients with Alzheimer's disease (AD), Lewy body dementia (LBD), frontotemporal dementia (FTD) and progressive supranuclear palsy (PSP).

Methods: Plasma phosphorylated tau at threonine-181 (p-tau181), amyloid beta (Αβ)42, Aβ40, neurofilament light (NfL) and glial fibrillar acidic protein (GFAP) were measured using highly sensitive single molecule immunoassays (Simoa) in a multicentre cohort of 300 participants (controls=73, amyloid positive mild cognitive impairment (MCI+) and AD dementia=63, LBD=117, FTD=28, PSP=19). LBD participants had known positron emission tomography (PET)-Aβ status.

In Vivo F-Flortaucipir PET Does Not Accurately Support the Staging of Progressive Supranuclear Palsy.

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by neuroglial tau pathology. A new staging system for PSP pathology postmortem has been described and validated. We used a data-driven approach to test whether postmortem pathologic staging in PSP can be reproduced in vivo with F-flortaucipir PET.

Neuropsychological performance in young adults with cannabis use disorder.

Background And Aims: Cannabis is a commonly used recreational drug in young adults. The worldwide prevalence in 18- to 25-year-olds is approximately 35%. Significant differences in cognitive performance have been reported previously for groups of cannabis users.

[F]-AV-1451 binding in the substantia nigra as a marker of neuromelanin in Lewy body diseases.

While [F]-AV-1451 was developed as a PET radiotracer with high affinity for hyperphosphorylated tau, it has been proposed that loss of 'off-target' [F]-AV-1451 binding to neuromelanin in the substantia nigra could be a surrogate marker of Lewy body diseases. [F]-AV-1451 binding was measured in the substantia nigra of patients with Parkinson's disease ( = 35), dementia with Lewy bodies ( = 10) and separate control groups ( = 37; = 14). Associations with motor symptoms, cognition and disease duration were evaluated using linear regression models.

Molecular pathology and synaptic loss in primary tauopathies: an 18F-AV-1451 and 11C-UCB-J PET study.

The relationship between in vivo synaptic density and molecular pathology in primary tauopathies is key to understanding the impact of tauopathy on functional decline and in informing new early therapeutic strategies. In this cross-sectional observational study, we determine the in vivo relationship between synaptic density and molecular pathology in the primary tauopathies of progressive supranuclear palsy and corticobasal degeneration as a function of disease severity. Twenty-three patients with progressive supranuclear palsy and 12 patients with corticobasal syndrome were recruited from a tertiary referral centre.

Sex Differences in Neuropsychological Functioning are Domain-Specific in Adolescent and Young Adult Regular Cannabis Users.

Objective: Adolescence into young adulthood represents a sensitive period in which brain development significantly diverges by sex. Regular cannabis use by young people is associated with neuropsychological vulnerabilities, but the potential impact of sex on these relationships is unclear.

Method: In a cross-sectional study, we examined sex differences in multi-domain neuropsychological functioning using the Cambridge Neuropsychological Test Automated Battery (CANTAB) and tested whether sex moderated the relationship between cognitive performance and age of initiation, frequency of cannabis use, amount of cannabis use, and withdrawal symptoms in at least weekly adolescent and young adult cannabis users (n = 171; aged 13-25 years; 46.

Synaptic density in carriers of C9orf72 mutations: a [ C]UCB-J PET study.

Synaptic loss is an early and clinically relevant feature of many neurodegenerative diseases. Here we assess three adults at risk of frontotemporal dementia from C9orf72 mutation, using [ C]UCB-J PET to quantify synaptic density in comparison with 19 healthy controls and one symptomatic patient with behavioural variant frontotemporal dementia. The three pre-symptomatic C9orf72 carriers showed reduced synaptic density in the thalamus compared to controls, and there was an additional extensive synaptic loss in frontotemporal regions of the symptomatic patient.

Imaging tau burden in dementia with Lewy bodies using [F]-AV1451 positron emission tomography.

Alzheimer's disease (AD) pathology is frequently observed as a comorbidity in people with dementia with Lewy bodies (DLB). Here, we evaluated the in vivo distribution of tau burden and its influence on the clinical phenotype of DLB. Tau deposition was quantified using [F]-AV1451 positron emission tomography in people with DLB (n = 10), AD (n = 27), and healthy controls (n = 14).

C-UCB-J synaptic PET and multimodal imaging in dementia with Lewy bodies.

Objective: Dementia with Lewy bodies (DLB) is a common cause of dementia, but atrophy is mild compared to Alzheimer's disease. We propose that DLB is associated instead with severe synaptic loss, and we test this hypothesis in vivo using positron emission tomography (PET) imaging of C-UCB-J, a ligand for presynaptic vesicle protein 2A (SV2A), a vesicle membrane protein ubiquitously expressed in synapses.

Methods: We performed C-UCB-J PET in two DLB patients (an amyloid-negative male and an amyloid-positive female in their 70s) and 10 similarly aged healthy controls.

The revised Addenbrooke's Cognitive Examination can facilitate differentiation of dementia with Lewy bodies from Alzheimer's disease.

Objectives: Dementia with Lewy bodies (DLB) is a major cause of degenerative dementia, yet the diagnosis is often missed or mistaken for Alzheimer's disease (AD). We assessed whether the revised Addenbrooke's Cognitive Examination (ACE-R), a brief test for dementia, differentiates DLB from AD.

Methods: We first compared baseline ACE-R performance in 76 individuals with DLB, 40 individuals with AD and 66 healthy controls.

In vivo neuroinflammation and cerebral small vessel disease in mild cognitive impairment and Alzheimer's disease.

Introduction: Associations between cerebral small vessel disease (SVD) and inflammation have been largely examined using peripheral blood markers of inflammation, with few studies measuring inflammation within the brain. We investigated the cross-sectional relationship between SVD and in vivo neuroinflammation using [C]PK11195 positron emission tomography (PET) imaging.

Methods: Forty-two participants were recruited (according to NIA-AA guidelines, 14 healthy controls, 14 mild Alzheimer's disease, 14 amyloid-positive mild cognitive impairment).

Synaptic Loss in Primary Tauopathies Revealed by [ C]UCB-J Positron Emission Tomography.

Background: Synaptic loss is a prominent and early feature of many neurodegenerative diseases.

Objectives: We tested the hypothesis that synaptic density is reduced in the primary tauopathies of progressive supranuclear palsy (PSP) (Richardson's syndrome) and amyloid-negative corticobasal syndrome (CBS).

Methods: Forty-four participants (15 CBS, 14 PSP, and 15 age-/sex-/education-matched controls) underwent PET with the radioligand [ C]UCB-J, which binds to synaptic vesicle glycoprotein 2A, a marker of synaptic density; participants also had 3 Tesla MRI and clinical and neuropsychological assessment.

Biased interpretation in paranoia and its modification.

Background And Objectives: Cognitive models of psychosis implicate interpretation biases as one of the mechanisms involved in the formation and maintenance of symptoms. First we measured the strength of association between interpretation biases and psychosis-relevant traits. Next we manipulated these biases and quantified the effects of doing so on psychosis-relevant outcomes.