Biodistribution and radiation dosimetry of [(11)C]choline: a comparison between rat and human data.

Purpose: Methyl-(11)C-choline ([(11)C]choline) is a radiopharmaceutical used for oncological PET studies. We investigated the biodistribution and biokinetics of [(11)C]choline and provide estimates of radiation doses in humans.

Methods: The distribution of [(11)C]choline was evaluated ex vivo in healthy rats (n=9) by measuring the radioactivity of excised organs, and in vivo in tumour-bearing rats (n=4) by PET.

68Ga-chloride PET reveals human pancreatic adenocarcinoma xenografts in rats--comparison with FDG.

Purpose: The aim of the study was to compare (68)Ga-chloride with 2-[(18)F]fluoro-2-deoxy-D: -glucose (FDG) for the imaging of pancreatic xenografts.

Procedures: Rats with subcutaneous human pancreatic adenocarcinoma xenografts were evaluated in vivo by dynamic positron emission tomography (PET) and ex vivo by measuring radioactivity of excised tissues and by digital autoradiography of tumor cryosections.

Results: Both tracers were capable of delineating all subcutaneous tumors from surrounding tissues by PET.

Preliminary study of carbon-11 methionine PET in the evaluation of early response to therapy in advanced breast cancer.

Objective: Breast cancer is one of the principal oncological challenges in the Western world. Currently, there are only a few reliable predictive methods for monitoring treatment. We investigated the ability of carbon-11 methionine ("11C-MET) positron emission tomography (PET) to evaluate early response to therapy in advanced breast cancer.

Visualization and quantification of neurokinin-1 (NK1) receptors in the human brain.

Purpose: This study was conducted to develop a new positron emission tomography (PET) method to visualize neurokinin-1 (NK(1)) receptor systems in the human brain in vivo in order to examine their neuroanatomical distribution and facilitate investigations of the role of substance P, NK(1) receptors, and NK(1) receptor antagonists in central nervous system (CNS) function and dysfunction.

Methods: PET studies were conducted in 10 healthy male volunteers using a novel selective, high-affinity NK(1) receptor antagonist labeled with fluorine-18 to very high specific radioactivity (up to 2000 GBq/micromol) [F-18]SPA-RQ. Data were collected in 3D mode for greatest sensitivity.

Synthesis and characterization of a potent, selective, radiolabeled substance-P antagonist for NK1 receptor quantitation: ([18F]SPA-RQ).

Purpose: To develop and characterize a radiolabelled Substance-P antagonist useful for quantitation of neurokinin-1 receptors in the brain via PET imaging.

Procedure: [18F]SPA-RQ (Substance-P antagonist - receptor quantifier) was synthesized in good yield and high specific activity by alkylation of a BOC protected phenolate anion using [18F]bromofluoromethane. Removal of the BOC protecting group with trifluoroacetic acid gave [18F]SPA-RQ.

Myocardial perfusion reserve and oxidative metabolism contribute to exercise capacity in patients with dilated cardiomyopathy.

Background: Exercise intolerance is a hallmark symptom in patients with heart failure; however, myocardial factors contributing to the limited exercise capacity are not fully characterized.

Methods: Twenty patients with stable heart failure resulting from idiopathic dilated cardiomyopathy (DCM) and 13 controls were studied. Myocardial perfusion, biventricular oxidative metabolism, and insulin-stimulated glucose uptake were measured using positron emission tomography and [(15)O]H(2)O, [(11)C]acetate, and [(18)F]FDG.

A novel electrophilic synthesis and evaluation of medium specific radioactivity (1R,2S)-4-[18F]fluorometaraminol, a tracer for the assessment of cardiac sympathetic nerve integrity with PET.

(1R,2S)-4-[18F]fluorometaraminol (4-[18F]FMR), a tracer for cardiac sympathetic innervation, was synthesized by electrophilic aromatic substitution. A trimethylstannyl precursor, protected with tert-butoxycarbonyl protecting groups, was radiofluorinated with high specific radioactivity [18F]F2. Specific radioactivity of 4-[18F]FMR, in average 11.

Kinetics of [(11)C]choline uptake in prostate cancer: a PET study.

Carbon-11 choline has recently been introduced as a potential tracer for tumour imaging with positron emission tomography (PET). We evaluated the kinetics of the uptake of [(11)C]choline in prostate cancer and benign prostatic hyperplasia. We also evaluated the association between the uptake of [(11)C]choline and the histological grade of malignancy, Gleason score, volume of the prostate and prostate-specific antigen (PSA).

Use of positron emission tomography with methyl-11C-choline and 2-18F-fluoro-2-deoxy-D-glucose in comparison with magnetic resonance imaging for the assessment of inflammatory proliferation of synovium.

Objective: To compare positron emission tomography (PET) and magnetic resonance imaging (MRI) in the evaluation of inflammatory proliferation of synovium.

Methods: Ten patients (mean +/- SD age 36 +/- 13 years) with inflammatory joint disease and with clinical signs of inflammation of the joint were studied. A new tracer for cellular proliferation, methyl-(11)C-choline ((11)C-choline), and a widely used tracer for the detection of inflammation and cancer, 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG), were applied for PET imaging, and the results were compared with the findings from gadolinium diethylenetriaminepentaacetic acid-enhanced MR images.

Exercise training improves biventricular oxidative metabolism and left ventricular efficiency in patients with dilated cardiomyopathy.

Objectives: The aim of this study was to determine the effect of exercise training on myocardial oxidative metabolism and efficiency in patients with idiopathic dilated cardiomyopathy (DCM) and mild heart failure (HF).

Background: Exercise training is known to improve exercise tolerance and quality of life in patients with chronic HF. However, little is known about how exercise training may influence myocardial energetics.

S-[18F]fluoromethyl-(+)-McN5652, a PET tracer for the serotonin transporter: evaluation in rats.

The [(18)F]fluoromethyl analog of (+)-McN5652 ([(18)F]FMe-McN) for imaging serotonin transporter (SERT) with positron emission tomography (PET) has recently been synthesized. We describe here the biological evaluation of [(18)F]FMe-McN in rats. Biodistribution studies of [(18)F]FMe-McN in rat brain ex vivo after an intravenous injection showed a high accumulation of radioactivity in the regions rich in SERT, such as raphe nuclei, hypothalamus, thalamus, substantia nigra, locus coeruleus, and amygdala.

Exercise training in chronic heart failure: beneficial effects on cardiac (11)C-hydroxyephedrine PET, autonomic nervous control, and ventricular repolarization.

Unlabelled: Abnormalities of autonomic nervous function are associated with a poor prognosis of patients with chronic heart failure (CHF). We studied the effects of a 6-mo exercise training program on Q-T interval dispersion, heart rate and blood pressure variability, baroreflex sensitivity, myocardial blood flow (MBF), and presynaptic sympathetic innervation in 13 patients with New York Heart Association class II-III heart failure.

Methods: MBF was measured with the H(2)(15)O and C(15)O technique.