A5030695255- Adenosine and Purinergic Signaling
- Medical Imaging Techniques and Applications
- Receptor Mechanisms and Signaling
- Radiopharmaceutical Chemistry and Applications
- Pharmacological Receptor Mechanisms and Effects
- 14-3-3 protein interactions
- Synthesis and Biological Evaluation
- Computational Drug Discovery Methods
- Lanthanide and Transition Metal Complexes
- Pharmacogenetics and Drug Metabolism
- Drug Transport and Resistance Mechanisms
- Neuroscience and Neuropharmacology Research
- Neuroendocrine Tumor Research Advances
- Neuroblastoma Research and Treatments
- Nitric Oxide and Endothelin Effects
- Glioma Diagnosis and Treatment
- Poisoning and overdose treatments
- Synthesis and biological activity
- Thyroid Cancer Diagnosis and Treatment
- Advanced MRI Techniques and Applications
- Thyroid Disorders and Treatments
- Cancer, Hypoxia, and Metabolism
- PI3K/AKT/mTOR signaling in cancer
- Metabolomics and Mass Spectrometry Studies
- Click Chemistry and Applications
Forschungszentrum Jülich
2016-2025
Klinik und Poliklinik für Nuklearmedizin
1996-2009
University of Würzburg
1997-2009
Abstract Changes in the organization of brain after recovery from aphasia were investigated by measuring increases regional cerebral blood flow (rCBF) during repetition pseudowords and verb generation. Six right‐handed patients who had recovered Wernicke's caused an infarction destroying left posterior perisylvian language zone compared with 6 healthy, volunteers. In control subjects, strong rCBF found hemisphere part superior middle temporal gyrus (Wernicke's area), generation task lateral...
This report describes the precursor synthesis and no-carrier-added (nca) radiosynthesis of new A(1) adenosine receptor (A(1)AR) antagonist [(18)F]8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine (CPFPX), 3, with fluorine-18 (half-life = 109.6 min). Nucleophilic radiofluorination tosylate 8-cyclopentyl-3-(3-tosyloxypropyl)-7-pivaloyloxymethyl-1-propylxanthine, 2, nca [(18)F]KF under aminopolyether-mediated conditions (Kryptofix 2.2.2/K(2)CO(3)) followed by deprotection was straightforward...
Identifying ligands targeting G protein coupled receptors (GPCRs) with novel chemotypes other than the physiological is a challenge for in silico screening campaigns. Here we present an approach that identifies chemotype by combining structural data random forest agonist/antagonist classifier and signal-transduction kinetic model. As test case, apply this to identify antagonists of human adenosine transmembrane receptor type 2A, attractive target against Parkinson's disease cancer. The...
Adenosine is an important neuromodulator. Basic cerebral effects of adenosine are exerted by the A 1 receptor (A AR), which accessible in vivo novel ligand [ 18 F]8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine ([ F]CPFPX) and positron emission tomography (PET). The present study investigates applicability kinetic models to describe kinetics F]CPFPX order quantify AR density vivo. Six healthy volunteers underwent dynamic PET scanning arterial blood sampling after bolus injection F]CPFPX....
Studies of plasma from mice, rats, and human volunteers evaluated methods for the extraction quantification positron emission tomography ligand [<sup>18</sup>F]8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine ([<sup>18</sup>F]CPFPX) identification its metabolites in by thin-layer chromatography high-performance liquid (HPLC). Analysis human, mouse, rat extracts HPLC identified four identical radioactive each species. The low mass radioligand administered to humans (0.5 - 5 nmol) prevented...
Assessment of iodine deficiency and monitoring supplementation programs demand rapid, simple, cost-effective methods for the determination urinary iodide concentrations. We propose a semiquantitative rapid test, based on iodide-catalyzed oxidation 3,3′,5,5′-tetramethylbenzidine by peracetic acid/H2O2, to yield colored products. The color chemical reaction is compared with categories pictogram corresponding three ranges: <100, 100–300, >300μ g/L (<0.79, 0.79–2.36, >2.36 μmol/L) test very easy...
X-ray fluorescence analysis is based on the principal that electron structure of stable iodine in thyroid excited by Americium-241 gamma rays to emit a characteristic radiation which proportional amount present gland. A stationary measuring system consisting 11.1 GBq Am-241 source and high-purity Germanium detector with spectrum analyser has been improved PC guided method for sonographic definition volume. The lower limit detectibility corresponds 0.01 mg Iodine per ml volume; vivo precision...
In order to deepen the understanding of electrospray ionisation collision-induced dissociation (ESI-CID) fragmentation reactions xanthine derivatives for identification metabolites using low-resolution liquid chromatography/mass spectrometry (LC/MS) analysis, basic experiments caffeine (1,3,7-trimethylxanthine) as model compound have been performed.Six deuterium isotopomers and one N1-ethylated homologue synthesized their ESI spectra obtained by LC/MS in combination with either standard or...
Liposomes are highly biocompatible and versatile drug carriers with an increasing number of applications in the field nuclear medicine diagnostics. So far, only negatively charged liposomes intercalated radiometals, e.g., 64Cu, 99mTc, have been reported. However, process cellular uptake by endocytosis is rather slow. Cellular can be accelerated recently developed cationic liposomes, which exhibit extraordinarily high membrane fusion ability. The aim present study was development formulation...
The prediction of in vivo clearance from vitro metabolism models such as liver microsomes is an established procedure drug discovery. potentials and limitations this approach have been extensively evaluated the pharmaceutical sector; however, not case for field positron emission tomography (PET) radiotracer development. application PET radiotracers classical drugs differs greatly with regard to amount substance administered. In typical imaging sessions, subnanomolar quantities are injected,...
Imaging of the A
In human blood, the PET radiotracer [18F]CPFPX (1) is metabolized to numerous metabolites, one (M1) being most prominent in plasma 30 min p.i. Because mass of injected tracer ≤5 nmol, concentrations are too low analyze. Human liver microsomes generate main metabolites having HPLC retention times identical those plasma. HPLC−MS tentatively identified M1 as 2. Synthesis 2 and spectra confirmed that assignment.