A5042415572- Radiopharmaceutical Chemistry and Applications
- Medical Imaging Techniques and Applications
- Hematological disorders and diagnostics
- Neuroscience and Neuropharmacology Research
- Receptor Mechanisms and Signaling
- Medical Imaging and Pathology Studies
- Advanced MRI Techniques and Applications
- Immune Response and Inflammation
- Blood disorders and treatments
- Lanthanide and Transition Metal Complexes
- Cancer, Hypoxia, and Metabolism
- Adenosine and Purinergic Signaling
- Orthopedic Infections and Treatments
- Glioma Diagnosis and Treatment
- Heat shock proteins research
- Analytical Methods in Pharmaceuticals
- Neurological disorders and treatments
- Chemical Reactions and Isotopes
- Synthesis and pharmacology of benzodiazepine derivatives
- Tuberculosis Research and Epidemiology
- Colorectal Cancer Treatments and Studies
- Venous Thromboembolism Diagnosis and Management
- Radioactive Decay and Measurement Techniques
- Neuroblastoma Research and Treatments
- Cell death mechanisms and regulation
Johns Hopkins University
2025
Cairo University
2024
Al-Neelain University
2024
Hamad Medical Corporation
2024
Hammersmith Hospital
1996-2008
Imperial College London
2006
Cyclotron (Netherlands)
1982-2001
Medical Research Council
1983-2001
National Hospital for Neurology and Neurosurgery
1994-1995
University College London
1994-1995
Five different methods for the estimation of binding potential, a measure B max /K d , [ 11 C]raclopride in human striatum were compared using data from dose ranging study neuroleptic CP-88,059-01. Binding potential was estimated indirectly, distribution volumes and cerebellum, both single- two-tissue compartment models with metabolite-corrected plasma curve as input function. The model also used direct estimate potential. In addition, obtained reference tissue cerebellum indirect Finally,...
Carbon-11-labeled flumazenil combined with positron emission tomography (PET) was used to measure the concentration (Bmax) of benzodiazepine (Bz) receptor in brain and its equilibrium dissociation constant (KD) for five normal subjects. The steady-state approach injecting tracer as a bolus high specific activity. In each subject two studies were carried out. first study performed at essentially zero occupancy, alone study. second occupancy about 50%, achieved by prolonged infusion nonlabeled...
Leukocytes labeled with technetium-99m hexamethylpropyleneamine oxime (HMPAO) were used in 100 patients: 32 suspected inflammatory bowel disease, 17 fever of unknown origin, 21 abdominal sepsis, 20 bone seven bronchiectasis, and three recent myocardial infarction. The distribution activity patients subsequently shown not to have disease was similar that previously described for indium-111-labeled leukocytes. However, this study, also seen the kidneys bladder occasionally gallbladder on both...
The early in vivo distribution of 111 Indium‐labelled granulocytes, recorded by dynamic imaging using a gamma camara and computer, varied according to the separation labelling technique. Following i.v. bolus injection, 4 kinetic patterns could be identified: (A) rapid transit through pulmonary vasculature, (B) delayed lung with clearance about 30 min, (C) complete retention lung, for up 10 followed slow release over period 1 2 h, (D) similar time course but subsequent heavy liver uptake....
We used PET and [<sup>18</sup>F]-6-L-fluorodopa ([<sup>18</sup>F]dopa) to measure the effect of a peripheral COMT inhibitor, entacapone, on extracerebral metabolism subsequent striatal uptake [<sup>18</sup>F]dopa. Four parkinsonian patients six age-matched normal controls were each scanned twice, once after carbidopa (150 mg) plus placebo entacapone (400 mg or 800 mg). Without premedication, by 90 minutes from injection, only 22% [<sup>18</sup>F] signal in plasma represented unmetabolized...
Development of hypoxia-targeted therapies has stimulated the search for clinically applicable noninvasive markers tumour hypoxia. Here, we describe validation [18F]fluoroetanidazole ([18F]FETA) as a hypoxia marker by positron emission tomography (PET). Cellular transport and retention [18F]FETA were determined in vitro under air vs nitrogen. Biodistribution metabolism radiotracer mice bearing MCF-7, RIF-1, EMT6, HT1080/26.6, HT1080/1-3C xenografts. Dynamic PET imaging was performed on...
The lipophilic complex, 99Tcm-hexamethylpropyleneamine oxime (HMPAO) is an efficient leucocyte label, and labels granulocytes with more stability than mononuclear leucocytes. recovery of 99Tcm-HMPAO granulocytes, expressed as the percentage injected granulocyte-associated activity circulating 40–45 min after injection, was 37% (S.E. 3%), similar to revocery 111In-labelled isolated labelled in plasma using tropolone. T1/2 blood 4.4 h 0.4 h), less that although when a correction made for 99Tcm...
The availability of a noninvasive method to detect and quantify apoptosis in tumours will enable tumour response several cancer therapies be assessed. We have synthesised two radiotracers, annexin V the N-succinimidyl-3-iodobenzoic acid (SIB) derivative V, labelled with radio-iodine (124I 125I) provided proof concept by assessing specific binding biodistribution these probes apoptotic cells tumours. also assessed uptake [124I]annexin mouse model apoptosis. RIF-1 induced undergo vitro showed...
Abstract Adenosine A 2A receptors are found on striatal neurones projecting to the external pallidum. KW‐6002 (istradefylline) is a potent and selective antagonist for adenosine in CNS acts inhibit excessive activity of this pathway MPTP marmoset model PD, thus relieving parkinsonism. The objectives study were investigate regional binding novel positron emission tomography tracer [ 11 C]KW‐6002 healthy human brain rat brain, along with receptor occupancy by cold at varying doses human....
Some anticancer drugs inhibit thymidylate synthase (TS), a key enzyme for thymidine nucleotide biosynthesis. Cells can compensate depleted levels by taking up extracellular via salvage pathway. We investigated the use of 2-[11C]thymidine positron emission tomography (PET) to measure kinetics in vivo humans.Five patients with advanced gastrointestinal cancer were PET scanned both before and 1 hour after oral administration TS inhibitor AG337 (THYMITAQ [nolatrexed]); seven control twice but...
Objective: The appropriate clinical management of indeterminate small renal masses can be improved based on accurate risk stratification. This study aimed to investigate the impact function uptake technetium-99m ( 99m Tc)-sestamibi, a widely available imaging agent that utilized identify oncocytomas and other benign/indolent masses. Methods: A retrospective cohort was conducted, involving 100 consecutive patients who underwent Tc-sestamibi single-photon emission computed tomography/computed...
There is an urgent need to develop non-invasive pharmacodynamic endpoints for the evaluation of new molecular therapeutics that inhibit signal transduction. We hypothesised that, when labelled appropriately, changes in choline kinetics could be used assess geldanamycin pharmacodynamics, which involves inhibition HSP90 chaperone-->Raf1-->Mitogenic Extracellular Kinase-->Extracellular Signal-Regulated Kinase 1 and 2 transduction pathway. Towards identifying a potential marker response, we have...
KW-6002, a xanthine-based adenosine A(2A) antagonist, was labelled with the positron emitter carbon-11 by O-methylation of its precursor, KF23325, using [(11)C]iodomethane and evaluated in rats as putative vivo radioligand for emission tomography (PET). Following intravenous injection [(11)C]KW-6002, radioactivity measured blood, plasma, peripheral tissues, discrete brain tissues over 2-h time period commensurate PET scanning. In brain, [(11)C]KW-6002 showed highest retention striata,...
The aim of this study was to assess simplified methods for deriving input functions estimating glucose metabolism using 18F-FDG-PET. Nine glioma patients underwent paired 18F-FDG-PET scans as part a phase II and the data used estimate metabolic rate (MRGlu) population-derived function (arterial from 14 scans) scaled single arterial blood sample taken at 20 min. Paired studies were performed in four further with stable disease least months following radiotherapy determine whether scaling...