Browsing by Subject "Organotechnetium Compounds"
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Item Open Access Assessing cardiac injury in mice with dual energy-microCT, 4D-microCT, and microSPECT imaging after partial heart irradiation.(Int J Radiat Oncol Biol Phys, 2014-03-01) Lee, Chang-Lung; Min, Hooney; Befera, Nicholas; Clark, Darin; Qi, Yi; Das, Shiva; Johnson, G Allan; Badea, Cristian T; Kirsch, David GPURPOSE: To develop a mouse model of cardiac injury after partial heart irradiation (PHI) and to test whether dual energy (DE)-microCT and 4-dimensional (4D)-microCT can be used to assess cardiac injury after PHI to complement myocardial perfusion imaging using micro-single photon emission computed tomography (SPECT). METHODS AND MATERIALS: To study cardiac injury from tangent field irradiation in mice, we used a small-field biological irradiator to deliver a single dose of 12 Gy x-rays to approximately one-third of the left ventricle (LV) of Tie2Cre; p53(FL/+) and Tie2Cre; p53(FL/-) mice, where 1 or both alleles of p53 are deleted in endothelial cells. Four and 8 weeks after irradiation, mice were injected with gold and iodinated nanoparticle-based contrast agents, and imaged with DE-microCT and 4D-microCT to evaluate myocardial vascular permeability and cardiac function, respectively. Additionally, the same mice were imaged with microSPECT to assess myocardial perfusion. RESULTS: After PHI with tangent fields, DE-microCT scans showed a time-dependent increase in accumulation of gold nanoparticles (AuNp) in the myocardium of Tie2Cre; p53(FL/-) mice. In Tie2Cre; p53(FL/-) mice, extravasation of AuNp was observed within the irradiated LV, whereas in the myocardium of Tie2Cre; p53(FL/+) mice, AuNp were restricted to blood vessels. In addition, data from DE-microCT and microSPECT showed a linear correlation (R(2) = 0.97) between the fraction of the LV that accumulated AuNp and the fraction of LV with a perfusion defect. Furthermore, 4D-microCT scans demonstrated that PHI caused a markedly decreased ejection fraction, and higher end-diastolic and end-systolic volumes, to develop in Tie2Cre; p53(FL/-) mice, which were associated with compensatory cardiac hypertrophy of the heart that was not irradiated. CONCLUSIONS: Our results show that DE-microCT and 4D-microCT with nanoparticle-based contrast agents are novel imaging approaches complementary to microSPECT for noninvasive assessment of the change in myocardial vascular permeability and cardiac function of mice in whom myocardial injury develops after PHI.Item Open Access Imaging biomarker roadmap for cancer studies.(Nature reviews. Clinical oncology, 2017-03) O'Connor, James PB; Aboagye, Eric O; Adams, Judith E; Aerts, Hugo JWL; Barrington, Sally F; Beer, Ambros J; Boellaard, Ronald; Bohndiek, Sarah E; Brady, Michael; Brown, Gina; Buckley, David L; Chenevert, Thomas L; Clarke, Laurence P; Collette, Sandra; Cook, Gary J; deSouza, Nandita M; Dickson, John C; Dive, Caroline; Evelhoch, Jeffrey L; Faivre-Finn, Corinne; Gallagher, Ferdia A; Gilbert, Fiona J; Gillies, Robert J; Goh, Vicky; Griffiths, John R; Groves, Ashley M; Halligan, Steve; Harris, Adrian L; Hawkes, David J; Hoekstra, Otto S; Huang, Erich P; Hutton, Brian F; Jackson, Edward F; Jayson, Gordon C; Jones, Andrew; Koh, Dow-Mu; Lacombe, Denis; Lambin, Philippe; Lassau, Nathalie; Leach, Martin O; Lee, Ting-Yim; Leen, Edward L; Lewis, Jason S; Liu, Yan; Lythgoe, Mark F; Manoharan, Prakash; Maxwell, Ross J; Miles, Kenneth A; Morgan, Bruno; Morris, Steve; Ng, Tony; Padhani, Anwar R; Parker, Geoff JM; Partridge, Mike; Pathak, Arvind P; Peet, Andrew C; Punwani, Shonit; Reynolds, Andrew R; Robinson, Simon P; Shankar, Lalitha K; Sharma, Ricky A; Soloviev, Dmitry; Stroobants, Sigrid; Sullivan, Daniel C; Taylor, Stuart A; Tofts, Paul S; Tozer, Gillian M; van Herk, Marcel; Walker-Samuel, Simon; Wason, James; Williams, Kaye J; Workman, Paul; Yankeelov, Thomas E; Brindle, Kevin M; McShane, Lisa M; Jackson, Alan; Waterton, John CImaging biomarkers (IBs) are integral to the routine management of patients with cancer. IBs used daily in oncology include clinical TNM stage, objective response and left ventricular ejection fraction. Other CT, MRI, PET and ultrasonography biomarkers are used extensively in cancer research and drug development. New IBs need to be established either as useful tools for testing research hypotheses in clinical trials and research studies, or as clinical decision-making tools for use in healthcare, by crossing 'translational gaps' through validation and qualification. Important differences exist between IBs and biospecimen-derived biomarkers and, therefore, the development of IBs requires a tailored 'roadmap'. Recognizing this need, Cancer Research UK (CRUK) and the European Organisation for Research and Treatment of Cancer (EORTC) assembled experts to review, debate and summarize the challenges of IB validation and qualification. This consensus group has produced 14 key recommendations for accelerating the clinical translation of IBs, which highlight the role of parallel (rather than sequential) tracks of technical (assay) validation, biological/clinical validation and assessment of cost-effectiveness; the need for IB standardization and accreditation systems; the need to continually revisit IB precision; an alternative framework for biological/clinical validation of IBs; and the essential requirements for multicentre studies to qualify IBs for clinical use.