Striatal and Extrastriatal Monoaminergic Disruption in Progressive Supranuclear Palsy.

Background: As a biomarker targeting vesicular monoamine transporter 2 (VMAT2), F-9-fluoropropyldihydrotetrabenazine (F-FP-DTBZ) positron emission tomography (PET) is highly accurate in diagnosing Parkinson's disease (PD) and assessing its severity. However, evidence is insufficient in patients with progressive supranuclear palsy (PSP).

Objective: We evaluated the striatal and extrastriatal monoaminergic disruption of PSP and differences in patterns between patients with PSP, PD, and healthy controls (HCs) using F-FP-DTBZ PET, as well as its correlations with the clinical characteristics of PSP.

F-FP-DTBZ PET/CT detectable associations between monoaminergic depletion in the putamen with rigidity and the pallidus with tremor in Parkinson's disease.

Introduction: The motor subtypes of Parkinson's disease (PD) are widely accepted and implemented. However, the motor subtypes have been thought to represent different stages of PD recently because some patients experience tremor-dominant (TD) conversion to the non-tremor-dominant subtype, such as postural instability-gait difficulty (PIGD). In this study, we explore the monoaminergic denervation features of the striatal and extra-striatal areas in patients with different subtypes of PD with F-9-fluoropropyl-(+)-dihydrotetrabenazine (F-FP-DTBZ) PET/CT.

Involvement of striatal motoric subregions in familial frontotemporal dementia with parkinsonism harboring the C9orf72 repeat expansions.

The chromosome 9 open reading frame 72 (C9ORF72) has been proposed as the causative gene of frontotemporal dementia with parkinsonism (FTDP), but its pathophysiological mechanism of parkinsonism is poorly understood. To explore the roles of striatal motor subdivisions in the pathogenesis of parkinsonism resulting from C9ORF72 repeat expansions in the FTDP, two patients with FTDP from one pedigree and seventeen healthy controls were enrolled. The participants received clinical interviews, physical examinations, genetic testing, [F]-fluorodeoxyglucose PET/MRI, and [F]-dihydrotetrabenazine PET/CT.

Corrigendum: Diagnostic value of striatal F-FP-DTBZ PET in Parkinson's disease.

[This corrects the article DOI: 10.3389/fnagi.2022.

Brain microglia activation and peripheral adaptive immunity in Parkinson's disease: a multimodal PET study.

Background: Abnormal activation of immune system is an important pathogenesis of Parkinson's disease, but the relationship between peripheral inflammation, central microglia activation and dopaminergic degeneration remains unclear.

Objectives: To evaluate the brain regional microglia activation and its relationship with clinical severity, dopaminergic presynaptic function, and peripheral inflammatory biomarkers related to adaptive immunity.

Methods: In this case-control study, we recruited 23 healthy participants and 24 participants with early-stage Parkinson's disease.

Clinical and Preclinical Neuroimaging Changes in Spinocerebellar Ataxia Type 12: A Study of Three Chinese Pedigrees.

Background: Spinocerebellar ataxia type 12 (SCA12) is a rare SCA subtype with unclear clinical and imaging features. Also, the radiological changes in prodromal and early stages remain unknown.

Methods: Ten symptomatic and two pre-symptomatic cases from three Chinese pedigrees received clinical assessments and imaging studies including routine magnetic resonance imaging (MRI), diffusion kurtosis imaging (DKI), and positron emission tomography (PET) using 18F-flurodeoxyglucose (FDG) to investigate glucose metabolism in brain and 18F-vesicle monoamine transporter 2 (VMAT2) to inspect the integrity of the dopaminergic neuron.

A Multi-Atlas-Based [18F]9-Fluoropropyl-(+)-Dihydrotetrabenazine Positron Emission Tomography Image Segmentation Method for Parkinson's Disease Quantification.

Objectives: [18F]9-fluoropropyl-(+)-dihydrotetrabenazine ([18F]-FP-DTBZ) positron emission tomography (PET) provides reliable information for the diagnosis of Parkinson's disease (PD). In this study, we proposed a multi-atlas-based [18F]-FP-DTBZ PET image segmentation method for PD quantification assessment.

Methods: A total of 99 subjects from Xuanwu Hospital of Capital Medical University were included in this study, and both brain PET and magnetic resonance (MR) scans were conducted.

Case Report: [F]PI2620 as a Tau Imaging Agent in Posterior Cortical Atrophy.

Posterior cortical atrophy (PCA) is widely considered as an atypical variant of Alzheimer disease and is characterized by a progressive decline in visual function. PCA has been investigated from the standpoints of brain structure and metabolism, but tau deposition and its relationship to disease severity still remain unclear. Here, we used a novel tau ligand, [F]PI2620, to visualize tau deposition in a PCA patient.

Decreased Penetrance of Parkinson's Disease in Elderly Carriers of Glucocerebrosidase Gene L444P/R Mutations: A Community-Based 10-Year Longitudinal Study.

Background: Heterozygous mutations in the glucocerebrosidase gene (GBA) have been shown to be an important genetic risk factor for Parkinson's disease (PD) worldwide. However, the penetrance of GBA heterozygote for L444P, the common mutation for Asian population, is not known in older Chinese people.

Objectives: To assess the conversion rate to PD in identified carriers of GBA L444P/R mutations in Chinese community-dwelling older adults.

Decreased Striatal Vesicular Monoamine Transporter Type 2 Correlates With the Nonmotor Symptoms in Parkinson Disease.

Objective: Nonmotor symptoms (NMS) are critical players in the patients' quality of life in Parkinson disease (PD). Vesicular monoamine transporter type 2 (VMAT2) has been reported owing to a role in affecting dopamine neurons in the striatum. Therefore, this study set out to characterize the relationship between VMAT2 distribution in the striatum in relation to the NMS in PD.

Diagnostic Approach of Early-Onset Dementia with Negative Family History: Implications from Two Cases of Early-Onset Alzheimer's Disease with De Novo PSEN1 Mutation.

For early-onset Alzheimer's disease (EOAD) cases with unclear family history, most cases are sporadic. Some cases are positive in genetic findings, that is, either incomplete penetrance or de novo mutation. We aimed to focus on EOAD cases with de novo mutations.

One-step preparation of [(18)F]FPBM for PET imaging of serotonin transporter (SERT) in the brain.

Serotonin transporters (SERT) in the brain play an important role in normal brain function. Selective serotonin reuptake inhibitors such as fluoxetine, sertraline, paroxetine, escitalopram, etc., specifically target SERT binding in the brain.

An improved preparation of [18F]FPBM: a potential serotonin transporter (SERT) imaging agent.

Introduction: In vivo positron emission tomography (PET) imaging of the serotonin transporter (SERT) is a valuable tool in drug development and in monitoring brain diseases with altered serotonergic function. We have developed a two-step labeling reaction for the preparation of the high serotonin affinity ligand [(18)F]FPBM ([(18)F]2-(2'-((dimethylamino)methyl)-4'-(3-fluoropropoxy)phenylthio)benzenamine, 1).

Method: To improve and automate the radiolabeling of [(18)F]FPBM, 1, an intermediate, [(18)F]3-fluoropropyltosylate, [(18)F]4, was prepared first, and then it was reacted with the phenol precursor (4-(2-aminophenylthio)-3-((dimethylamino)methyl)phenol, 3) to afford [(18)F]FPBM, 1.

Imaging of VMAT2 binding sites in the brain by (18)F-AV-133: the effect of a pseudo-carrier.

Objectives: Recently, 9-[(18)F]fluoropropyl-(+)-dihydrotetrabenazine ((18)F-AV-133) was reported as a new vesicular monoamine transporter (VMAT2) imaging agent for diagnosis of Parkinson's disease (PD). To shorten the preparation of (18)F-AV-133 and to make it more widely available, we evaluated a simple, rapid purification with a solid-phase extraction method (SPE) using an Oasis HLB cartridge instead of high pressure liquid chromatography (HPLC). The SPE method produced doses containing a pseudo-carrier, 9-hydroxypropyl-(+)-dihydrotetrabenazine (AV-149).

Synthesis and evaluation of novel tropane derivatives as potential PET imaging agents for the dopamine transporter.

A novel series of tropane derivatives containing a fluorinated tertiary amino or amide at the 2β position was synthesized, labeled with the positron-emitter fluorine-18 (t(1/2)=109.8 min), and tested as potential in vivo dopamine transporter (DAT) imaging agents. The corresponding chlorinated analogs were prepared and employed as precursors for radiolabeling leading to the fluorine-18-labeled derivatives via a one-step nucleophilic aliphatic substitution reaction.

Synthesis and evaluation of 18F labeled alanine derivatives as potential tumor imaging agents.

Introduction: This paper reports the synthesis and labeling of (18)F alanine derivatives. We also investigate their biological characteristics as potential tumor imaging agents mediated by alanine-serine-cysteine preferring (ASC) transporter system.

Methods: Three new (18)F alanine derivatives were prepared from corresponding tosylate-precursors through a two-step labeling reaction.

Optimization of automated radiosynthesis of [18F]AV-45: a new PET imaging agent for Alzheimer's disease.

Introduction: Accumulation of β-amyloid (Aβ) aggregates in the brain is linked to the pathogenesis of Alzheimer's disease (AD). Imaging probes targeting these Aβ aggregates in the brain may provide a useful tool to facilitate the diagnosis of AD. Recently, [(18)F]AV-45 ([(18)F]5) demonstrated high binding to the Aβ aggregates in AD patients.

Kinetic study for a stress testing of l,l-ethylenedicysteine by ultra-performance liquid chromatography/tandem mass spectrometry analysis.

This study proposed a stress testing to study oxidative stability and estimate the potential shelf-life of l,l-ethylenedicysteine (l,l-EC) under normal storage temperature condition (20-25 degrees C). l,l-EC was detected as a function of time at four different temperatures by ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS). The degradation of l,l-EC followed the first order kinetics, and the temperature-dependent kinetics was well described by the linear Arrhenius equation.