China
Africa
Explore chapters and articles related to this topic
Radionuclide-based Diagnosis and Therapy of Prostate Cancer
Published in Michael Ljungberg, Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
Sven-Erik Strand, Mohamed Altai, Joanna Strand, David Ulmert
Technetium-99m is the most readily available and commonly used radionuclide in nuclear medicine. This stems from the fact that 99mTc can be produced from decaying 99Mo using a 99Mo/99mTc generator, which is readily available at affordable prices. 99mTc decays by internal conversion to its ground state 99Tc with a half-life of 6.04 h. The 140 keV emitted γ-photon is well suited for imaging using gamma cameras and SPECT. Indium-111 is also a γ-emitting radionuclide with two 172 keV and 245 keV gamma emissions and 2.8 days half-life. This relatively long half-life renders 111In suitable for radiolabelling of different classes of targeting agents, with varying in vivo kinetics for imaging. One major advantage with indium isotopes is that they could easily be incorporated into different biomolecules using different chelating agents (see below). Other less available SPECT radionuclides include 67Ga (Eγ= 93.3 keV (35.7%) and 184.6 keV (19.7%) with 3.3 days half-life and the radiohalogen 123I (Eγ= 159 keV, t1/2= 13.2 h) a decay product of the daughter 123Xe produced after proton bombardment of 124Xe in a (p, 2n) reaction.
Evaluation of the Potential of Microspherical Systems for Regional Therapy in the Tumor-Bearing Liver and Kidney Using Techniques in Nuclear Medicine
Published in Neville Willmott, John Daly, Microspheres and Regional Cancer Therapy, 2020
Jacqueline A. Goldberg, James H. McKillop, Colin S. McArdle
Indium-111 (111In) has complex metallic chemistry.1,6 It emits gamma rays, which are somewhat above the ideal energy for gamma camera imaging, although reasonable images can still be obtained. It is not available from a generator and thus must be ordered specifically when required. The longer physical half-life results in an increased radiation dose to the patient for the same administered activity compared with 99mTc. The higher energy photons make 111In suitable for use with 99mTc in dual-tracer studies, e.g., before and after an intervention, because the gamma camera or in vitro counter can be set up to discriminate between the different photon energies. The longer half-life makes 111In a possible tracer for studying microsphere stability. Indium-113m (113mIn) has identical chemical properties to 111In but a much shorter physical half-life. It is available from a generator and has photonenergies sufficiently different from 99mTc to allow dual-tracer experiments.
Miscellaneous procedures
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
Indium scanning may be useful in acute infection, inflammatory bowel disease, renal tract infections or when 99Tc-HMPAO is not available. Imaging is normally performed 18–24 hours after injection. However, the performance of an early (1–3 hour) study, especially when inflammatory bowel disease is suspected, may be appropriate. Additional imaging may be done at 48 hours. SPECT imaging of relevant sites may also be useful in selected cases. The 67-hour half-life of indium-111 (111In) allows for delayed imaging, which may be valuable for musculoskeletal infection [39].
Pulmonary translocation of ultrafine carbon particles in COPD and IPF patients
Published in Inhalation Toxicology, 2022
Mikaela Qvarfordt, Martin Anderson, Alejandro Sanchez-Crespo, Maria Diakopoulou, Magnus Svartengren
To determine the percentage of free indium-111 activity at exposure, a sample of the inhaled aerosol was collected from the exposure bag on a 0.2 µm pore size Teflon filter (Pall Laboratory, Port Washington, NY, USA). The activity in the filter was then measured in a 3-inch sodium iodine well detector (Wizard Gamma Counter, PerkinElmer Inc., Waltham, MA, USA) with decay and background corrections. Thereafter, the filter was placed inside of a dialysis membrane tube (Spectrum Laboratories, New Brunswick, NJ, USA) together with 10 ml of 0.9% sodium chloride solution. The membrane tube was then submerged into 200 ml of 0.9% sodium chloride equilibration buffer. The activity concentration of free Indium-111 in the buffer was then determined after 24 hours of equilibration, by measuring the activity from a 20 ml buffer sample in the well counter. The percentage of inhaled free Indium-111 was then calculated as decay and background corrected total buffer activity in percent of reference filter activity. This process was subsequently repeated throughout the entire follow-up period for each subject to obtain an estimate of the chemical stability of the 111In-UFC labeling.
Preclinical optimization of Ly6E-targeted ADCs for increased durability and efficacy of anti-tumor response
Published in mAbs, 2021
Josefa Dela Cruz Chuh, MaryAnn Go, Yvonne Chen, Jun Guo, Hanine Rafidi, Danielle Mandikian, Yonglian Sun, Zhonghua Lin, Kellen Schneider, Pamela Zhang, Rajesh Vij, Danielle Sharpnack, Pamela Chan, Cecile de la Cruz, Jack Sadowsky, Dhaya Seshasayee, James T. Koerber, Thomas H. Pillow, Gail D. Phillips, Rebecca K Rowntree, C. Andrew Boswell, Katherine R. Kozak, Andrew G. Polson, Paul Polakis, Shang-Fan Yu, Peter S. Dragovich, Nicholas J. Agard
Iodine-125 (125I) was obtained as sodium iodide in 0.1 N sodium hydroxide from Perkin Elmer. Indirect iodinations were done as previously described using 1 mCi of 125I (3 µL) to randomly iodinate tyrosine residues at a specific activity of ~5-8 mCi/mg with 125I using iodogen tubes (Pierce). Indium-111 (111In) was obtained as indium chloride in 0.05 N hydrogen chloride from BWX Technologies, Inc. Radiosynthesis of 111In-labeled antibodies (5–9 mCi/mg) was achieved through incubation of 111InCl3 and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-conjugated (site directed through cysteines) monoclonal antibody in 0.1 mol/L HEPES pH 5.5 at 37°C. Purification of all radioimmunoconjugates was achieved using NAP5 columns equilibrated in PBS and confirmed by radio-size-exclusion chromatography.
The potential of PSMA-targeted alpha therapy in the management of prostate cancer
Published in Expert Review of Anticancer Therapy, 2020
Luca Filippi, Agostino Chiaravalloti, Orazio Schillaci, Oreste Bagni
PSMA overexpression has been demonstrated also in the neovasculature associated with many malignancies and, even to a lesser extent, in peripheral and central nervous system and in duodenal epithelial cells [23]. Of note, PSMA expression in PCa resulted to be associated with biochemical recurrence after surgery and correlated with disease-specific lethality [24]. In 1996 Food and Drug Administration (FDA) approved an indium-111 (111In) radioimmunoconjugate, namely 111In-capromab (ProstaScint®), for the detection of PSMA through single-photon emission computed tomography (SPECT). Nevertheless, 111In-capromab presents several limitations in clinical practice: poor spatial resolution of SPECT technology, immunogenicity and its capability of recognizing only the intracellular portion of PSMA structure [25].