Search results for "POSITRON EMISSION TOMOGRAPHY"
showing 10 items of 235 documents
Synthesis of [11C]SSR149415 and preliminary imaging studies using positron emission tomography.
2010
Abstract SSR149415 was the first non-peptide vasopressin-(V1b) receptor antagonist reported. It has been used to probe the role of V1b receptors in animal models of depression, aggression, and stress-anxiety, and was progressed to clinical trials for the treatment of depression. Due to the interest in V1b receptors as a therapeutic target and the growing use of SSR149415 in preclinical research, we developed a method to label SSR145419 with carbon-11 and have studied its pharmacokinetics in non-human primates using positron emission tomography.
DMAP-BODIPY Alkynes: A Convenient Tool for Labeling Biomolecules for Bimodal PET-Optical Imaging
2014
Several new boron dipyrromethene/N,N-dimethylaminopyridine (BODIPY-DMAP) assemblies were synthesized as precursors for bimodal imaging probes (optical imaging, OI/positron emission tomography, PET). The photophysical properties of the new compounds were also studied. The first proof-of-concept was obtained with the preparation of several new BODIPY-labeled bombesins and evaluation of the affinity for bombesin receptors by using a competition binding assay. Fluorination reactions were investigated on DMAP-BODIPY precursors as well as on DMAP-BODIPY-labeled bombesins. Chemical modifications on the BODIPY core were also performed to obtain luminescent dyes emitting in the therapeutic window (6…
Clinical evaluation of [68Ga]Ga-DATA-TOC in comparison to [68Ga]Ga-DOTA-TOC in patients with neuroendocrine tumours
2019
Abstract Introduction [68Ga]Ga-DATA-TOC is a new radiolabelled somatostatin-analogue for positron emission tomography (PET) imaging of neuroendocrine tumours. Its advantage over DOTA-conjugated compounds is the possibility for high-efficiency labelling with gallium-68 quickly at room temperature with high reliability and without the need for product purification, which enables the development of an instant kit-type labelling method. We evaluated its imaging characteristics in patients with neuroendocrine tumours in comparison to [68Ga]Ga-DOTA-TOC. Methods 19 patients imaged with [68Ga]Ga-DATA-TOC were retrospectively analysed and uptake in normal tissues was compared with a group of 19 pati…
Establishment of a [18F]-FDG-PET/MRI Imaging Protocol for Gastric Cancer PDX as a Preclinical Research Tool
2020
Purpose The utility of 18-fluordesoxyglucose positron emission tomography ([18F]-FDG-PET) combined with computer tomography or magnetic resonance imaging (MRI) in gastric cancer remains controversial and a rationale for patient selection is desired. This study aims to establish a preclinical patient-derived xenograft (PDX) based [18F]-FDG-PET/MRI protocol for gastric cancer and compare different PDX models regarding tumor growth and FDG uptake. Materials and methods Female BALB/c nu/nu mice were implanted orthotopically and subcutaneously with gastric cancer PDX. [18F]-FDG-PET/MRI scanning protocol evaluation included different tumor sizes, FDG doses, scanning intervals, and organ-specific …
Phase 0/1 of Positron Emission Tomography (PET) imaging agent [18F]-ODS2004436 as a marker of EGFR mutation in patients with non-small cell lung canc…
2018
e24184Background: Multiple EGFR tyrosine kinase inhibitors (TKIs) are approved for treatment of NSCLC harboring EGFR activating mutations or secondary TKIs resistant mutation. We evaluate a new PET...
Improved inter-observer agreement of an expert review panel in an oncology treatment trial--Insights from a structured interventional process.
2015
Abstract Purpose Oncologic imaging is a key for successful cancer treatment. While the quality assurance (QA) of image acquisition protocols has already been focussed, QA of reading and reporting offers still room for improvement. The latter was addressed in the context of a prospective multicentre trial on fluoro-deoxyglucose (FDG)–positron-emission tomography (PET)/CT-based chemoradiotherapy for locally advanced non-small cell lung cancer (NSCLC). Material and methods An expert panel was prospectively installed performing blinded reviews of mediastinal NSCLC involvement in FDG–PET/CT. Due to a high initial reporting inter-observer disagreement, the independent data monitoring committee (I…
Blood flow and metabolic microenvironment of brain tumors
1994
Summarizing thesein vivo data in the context of brain tumor therapy, the following aspects are of particular importance: Low and heterogeneous tumor blood flow may — in addition to the limiting effects of the blood-brain barrier — result in compromised delivery of drugs from blood to the tissue. Low tumor pO2 reduces sensitivity to standard radiation and ‘O2-dependent’ anticancer drugs. Treatment efficacy may be further altered by changes of tumor pH. Particularly acidosis can decrease radiation sensitivity and modulate the cytotoxicity of anticancer drugs. In the following presentations, these aspects will be discussed regardingin vivo data obtained with positron emission tomography.
Theragnostic Use of Radiolabelled Dota-Peptides in Meningioma: From Clinical Demand to Future Applications.
2019
Meningiomas account for approximately 30% of all new diagnoses of intracranial masses. The 2016 World Health Organization’s (WHO) classification currently represents the clinical standard for meningioma’s grading and prognostic stratification. However, watchful waiting is frequently the chosen treatment option, although this means the absence of a certain histological diagnosis. Consequently, MRI (or less frequently CT) brain imaging currently represents the unique available tool to define diagnosis, grading, and treatment planning in many cases. Nonetheless, these neuroimaging modalities show some limitations, particularly in the evaluation of skull base lesions. The emerging evidence supp…
Hunting for the high-affinity state of G-protein-coupled receptors with agonist tracers: Theoretical and practical considerations for positron emissi…
2019
Abstract The concept of the high‐affinity state postulates that a certain subset of G‐protein‐coupled receptors is primarily responsible for receptor signaling in the living brain. Assessing the abundance of this subset is thus potentially highly relevant for studies concerning the responses of neurotransmission to pharmacological or physiological stimuli and the dysregulation of neurotransmission in neurological or psychiatric disorders. The high‐affinity state is preferentially recognized by agonists in vitro. For this reason, agonist tracers have been developed as tools for the noninvasive imaging of the high‐affinity state with positron emission tomography (PET). This review provides an…