F-fallypride and C-methionine positron emission tomography/computed tomography for the study of prolactinomas and nonfunctioning pituitary adenomas: A case series.

Some studies have assessed the expression of dopaminergic dopamine 2 (D2)/3 receptors in prolactinomas and nonfunctioning pituitary adenomas (NFPA) by positron emission tomography/computed tomography (PET/CT) with C-raclopride, proving that this modality can be useful to predict the response to treatment with dopamine agonists. However, the use of C-labeled radiotracers is limited, as it requires a cyclotron in the PET center. F-fallypride is a radiotracer that has proven useful in assessing the expression of D2/3 receptors.

Prognostic value of imaging markers from 18FDG-PET/CT in paediatric patients with Hodgkin lymphoma.

Objective: Identification of imaging prognostic parameters for early therapy personalisation to reduce treatment-related morbidity in paediatric Hodgkin lymphoma (HL). Our aim was to evaluate quantitative markers from baseline 2-[18F]fluoro-2-deoxy-d-glucose PET/CT as prognostic factors for treatment outcomes. Another goal was assessing the prognostic value of Deauville score at interim PET/CT.

A new naphthalene derivative with anti-amyloidogenic activity as potential therapeutic agent for Alzheimer's disease.

The aggregation of β-amyloid peptides is associated to neurodegeneration in Alzheimer's disease (AD) patients. Consequently, the inhibition of both oligomerization and fibrillation of β-amyloid peptides is considered a plausible therapeutic approach for AD. Herein, the synthesis of new naphthalene derivatives and their evaluation as anti-β-amyloidogenic agents are presented.

Oxidant and Antioxidant Effects of Gentisic Acid in a Lu-Labelled Methionine-Containing Minigastrin Analogue.

Background: The radiolabelling of receptor-binding peptides for therapy is a challenge since the peptide itself is exposed (during labelling, storage and transport) to radiation-induced damage, directly or indirectly, in aqueous solution. Hence, the use of radiostabilizers seems to be mandatory, especially in peptide molecules that contain radiation-sensitive amino acids.

Objective: The aim of this study was to investigate the effect of two stabilizers, gentisic acid and methionine, to delve into how each of them affects the radiolabelling and stability of the minigastrin analogue [177Lu]Lu-DOTA-His-His-Glu-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2 through the analysis of the 22 species distinguished over time by an optimized HPLC system.

Biological Assessment of a F-Labeled Sulforhodamine 101 in a Mouse Model of Alzheimer's Disease as a Potential Astrocytosis Marker.

Neurodegenerative diseases have mainly been associated with neuronal death. Recent investigations have shown that astroglia may modulate neuroinflammation in the early and late stages of the disease. [C]Deuterodeprenyl ([C]DED) is a tracer that has been used for reactive astrocyte detection in Alzheimer's disease, Creutzfeldt-Jakob disease and amyotrophic lateral sclerosis, among others, with some limitations.

Cocaine treatment before pregnancy differentially affects the anxiety and brain glucose metabolism of lactating rats if performed during adulthood or adolescence.

Cocaine exposure disrupts the maternal behavior of lactating rats, yet it is less known whether it alters the affective changes that accompany motherhood. As the long-term action of cocaine on anxiety varies according to the developmental stage of the individuals, this study aimed to compare the effect of a chronic treatment with cocaine to adult and adolescent non-pregnant females on their anxiety-like behavior and basal brain metabolic activity during lactation. Thus, adult and adolescent virgin rats were exposed to cocaine (0.

Dosimetry and Toxicity Studies of the Novel Sulfonamide Derivative of Sulforhodamine 101([18F]SRF101) at a Preclinical Level.

Background: The SR101 N-(3-[18F]Fluoropropyl) sulfonamide ([18F]SRF101) is a Sulforhodamine 101 derivative that was previously synthesised by our group. The fluorescent dye SR101 has been reported as a marker of astroglia in the neocortex of rodents in vivo.

Objective: The aim of this study was to perform a toxicological evaluation of [18F]SRF101 and to estimate human radiation dosimetry based on preclinical studies.

Image-Guided Development of Heterocyclic Sulfoxides as Ligands for Tau Neurofibrillary Tangles: From First-in-Man to Second-Generation Ligands.

Positron emission tomography (PET) imaging of misfolded protein aggregates that form in neurodegenerative processes of the brain is key to providing a robust marker for improved diagnosis and evaluation of treatments. We report the development of advanced radiotracer candidates based on the sulfoxide scaffold found in proton pump inhibitors (lansoprazole, prevacid) with inherent affinity to neurofibrillary tangles in Alzheimer's disease and related disorders (e.g.

Ga-PSMA and C-Choline comparison using a tri-modality PET/CT-MRI (3.0 T) system with a dedicated shuttle.

Background: The aim of this study was to prospectively compare the detection rate of Ga-PSMA versus C-Choline in men with prostate cancer with biochemical recurrence and to demonstrate the added value of a tri-modality PET/CT-MRI system.

Methods: We analysed 36 patients who underwent both C-Choline PET/CT and Ga-PSMA PET/CT scanning within a time window of 1-2 weeks. Additionally, for the Ga-PSMA scan, we used a PET/CT-MRI (3.

Synthesis of an AlF radiofluorinated GLU-UREA-LYS(AHX)-HBED-CC PSMA ligand in an automated synthesis platform.

Background: Overexpression of prostatic membrane antigen (PSMA) is associated with the progression and prognosis of prostate cancer. There are numerous studies using this peptide with the Ga radionuclide. Previous methods to synthetize F-labeled PSMA ligands with complexes [F]AlF have been achieved.

Synthesis of [18F]2B-SRF101: A Sulfonamide Derivative of the Fluorescent Dye Sulforhodamine 101.

Background: The red fluorescent dye Sulforhodamine 101 (SR101) has been used in neuroscience research as a useful tool for staining of astrocytes, since it has been reported as a marker of astroglia in the neocortex of rodents in vivo. The aim of this work is to label SR101 with positron emission radionuclides, in order to provide a radiotracer to study its biological behavior. This is the first attempt to label SR101 by [18F], using a chemical derivatization via a sulfonamidelinker and a commercially available platform.

Automated One-pot Radiosynthesis of [11C]S-adenosyl Methionine.

Background: Glycine N-methyltransferase is an enzyme overexpressed in some neoplastic tissues. It catalyses the methylation of glycine using S-adenosyl methionine (SAM or AdoMet) as substrate. SAM is involved in a great variety of biochemical processes, including transmethylation reactions.

Decreased Brain Neurokinin-1 Receptor Availability in Chronic Tennis Elbow.

Substance P is released in painful and inflammatory conditions, affecting both peripheral processes and the central nervous system neurokinin 1 (NK1) receptor. There is a paucity of data on human brain alterations in NK1 expression, how this system may be affected by treatment, and interactions between central and peripheral tissue alterations. Ten subjects with chronic tennis elbow (lateral epicondylosis) were selected out of a larger (n = 120) randomized controlled trial evaluating graded exercise as a treatment for chronic tennis elbow (lateral epicondylosis).

⁶⁸Ga-NOTA-UBI-29-41 as a PET Tracer for Detection of Bacterial Infection.

Unlabelled: The cationic peptide (68)Ga-NOTA-UBI-29-41 was synthesized and characterized. Biodistribution and PET/CT examinations were performed for evaluation of its biologic behavior. Differentiation of infection from sterile inflammation was investigated using microbiology methods at the sites of bacterial infections.

PET and the multitracer concept in the study of neurodegenerative diseases.

The complexity of the pathological reactions of the brain to an aggression caused by an internal or external noxa represents a challenge for molecular imaging. Positron emission tomography (PET) can indicate anatomopathological changes involved in the development of different clinical symptoms in patients with neurodegenerative disorders. PET and the multitracer concept can provide information from different systems in the brain tissue building an image of the whole disease.

Fluorodeoxyglucose PET in Neurology and Psychiatry.

PET imaging with the most widely available PET tracer, 2-deoxy-2-[(18)F]fluoro-d-glucose (FDG), is a powerful tool in the differential diagnosis of numerous neurologic and psychiatric disorders, particularly in early disease stages. It also plays an important role in the longitudinal evaluation of treatment effects and the depiction of disease courses. A selection of established and eligible application areas of FDG PET in neurology and psychiatry, such as different types of dementia, epilepsy, schizophrenia, and bipolar disorder, are reviewed in this article.