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Spencer BA, McBride K, Hunt H, Jones T, Cherry SR, Badawi RD. Practical Considerations for Total-Body PET Acquisition and Imaging. Methods Mol Biol 2024; 2729:371-389. [PMID: 38006507 DOI: 10.1007/978-1-0716-3499-8_21] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
The world's first total-body PET/CT system has been in routine clinical and research use at UC Davis since 2019. The uEXPLORER total-body PET scanner has been designed with an axial field-of-view long enough to completely encompass most human subjects (194 cm or 76 inches long), allowing for a 15-68-fold gain in the PET signal collection efficiency over conventional PET scanners. A high-sensitivity PET scanner that can image the entire subject with a single bed position comes with new benefits and challenges to consider for efficient and practical use. In this chapter, we discuss the common clinical and research imaging protocols implemented at our institution, along with the appropriate technical and practical considerations of total-body PET imaging.
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Affiliation(s)
- Benjamin A Spencer
- Department of Radiology, University of California-Davis, Sacramento, CA, USA.
- Department of Biomedical Engineering, University of California-Davis, Davis, CA, USA.
| | - Kristin McBride
- Department of Radiology, University of California-Davis, Sacramento, CA, USA
| | - Heather Hunt
- Department of Radiology, University of California-Davis, Sacramento, CA, USA
| | - Terry Jones
- Department of Radiology, University of California-Davis, Sacramento, CA, USA
| | - Simon R Cherry
- Department of Radiology, University of California-Davis, Sacramento, CA, USA
- Department of Biomedical Engineering, University of California-Davis, Davis, CA, USA
| | - Ramsey D Badawi
- Department of Radiology, University of California-Davis, Sacramento, CA, USA
- Department of Biomedical Engineering, University of California-Davis, Davis, CA, USA
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Boyuklieva R, Zagorchev P, Pilicheva B. Computational, In Vitro, and In Vivo Models for Nose-to-Brain Drug Delivery Studies. Biomedicines 2023; 11:2198. [PMID: 37626694 PMCID: PMC10452071 DOI: 10.3390/biomedicines11082198] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 07/27/2023] [Accepted: 08/02/2023] [Indexed: 08/27/2023] Open
Abstract
Direct nose-to-brain drug delivery offers the opportunity to treat central nervous system disorders more effectively due to the possibility of drug molecules reaching the brain without passing through the blood-brain barrier. Such a delivery route allows the desired anatomic site to be reached while ensuring drug effectiveness, minimizing side effects, and limiting drug losses and degradation. However, the absorption of intranasally administered entities is a complex process that considerably depends on the interplay between the characteristics of the drug delivery systems and the nasal mucosa. Various preclinical models (in silico, in vitro, ex vivo, and in vivo) are used to study the transport of drugs after intranasal administration. The present review article attempts to summarize the different computational and experimental models used so far to investigate the direct delivery of therapeutic agents or colloidal carriers from the nasal cavity to the brain tissue. Moreover, it provides a critical evaluation of the data available from different studies and identifies the advantages and disadvantages of each model.
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Affiliation(s)
- Radka Boyuklieva
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria;
- Research Institute, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria;
| | - Plamen Zagorchev
- Research Institute, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria;
- Department of Medical Physics and Biophysics, Faculty of Pharmacy, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria
| | - Bissera Pilicheva
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria;
- Research Institute, Medical University of Plovdiv, 4002 Plovdiv, Bulgaria;
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Advanced Neuroimaging Approaches to Pediatric Brain Tumors. Cancers (Basel) 2022; 14:cancers14143401. [PMID: 35884462 PMCID: PMC9318188 DOI: 10.3390/cancers14143401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 07/08/2022] [Indexed: 12/10/2022] Open
Abstract
Simple Summary After leukemias, brain tumors are the most common cancers in children, and early, accurate diagnosis is critical to improve patient outcomes. Beyond the conventional imaging methods of computed tomography (CT) and magnetic resonance imaging (MRI), advanced neuroimaging techniques capable of both structural and functional imaging are moving to the forefront to improve the early detection and differential diagnosis of tumors of the central nervous system. Here, we review recent developments in neuroimaging techniques for pediatric brain tumors. Abstract Central nervous system tumors are the most common pediatric solid tumors; they are also the most lethal. Unlike adults, childhood brain tumors are mostly primary in origin and differ in type, location and molecular signature. Tumor characteristics (incidence, location, and type) vary with age. Children present with a variety of symptoms, making early accurate diagnosis challenging. Neuroimaging is key in the initial diagnosis and monitoring of pediatric brain tumors. Conventional anatomic imaging approaches (computed tomography (CT) and magnetic resonance imaging (MRI)) are useful for tumor detection but have limited utility differentiating tumor types and grades. Advanced MRI techniques (diffusion-weighed imaging, diffusion tensor imaging, functional MRI, arterial spin labeling perfusion imaging, MR spectroscopy, and MR elastography) provide additional and improved structural and functional information. Combined with positron emission tomography (PET) and single-photon emission CT (SPECT), advanced techniques provide functional information on tumor metabolism and physiology through the use of radiotracer probes. Radiomics and radiogenomics offer promising insight into the prediction of tumor subtype, post-treatment response to treatment, and prognostication. In this paper, a brief review of pediatric brain cancers, by type, is provided with a comprehensive description of advanced imaging techniques including clinical applications that are currently utilized for the assessment and evaluation of pediatric brain tumors.
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Design of a functional cyclic HSV1-TK reporter and its application to PET imaging of apoptosis. Nat Protoc 2015; 10:807-21. [PMID: 25927390 DOI: 10.1038/nprot.2015.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Positron emission tomography (PET) is a sensitive and noninvasive imaging method that is widely used to explore molecular events in living subjects. PET can precisely and quantitatively evaluate cellular apoptosis, which has a crucial role in various physiological and pathological processes. In this protocol, we describe the design and use of an engineered cyclic herpes simplex virus 1-thymidine kinase (HSV1-TK) PET reporter whose kinase activity is specifically switched on by apoptosis. The expression of cyclic TK (cTK) in healthy cells leads to inactive product, whereas the activation of apoptosis through the caspase-3 pathway cleaves cTK, thus restoring its activity and enabling PET imaging. In addition to detailing the design and construction of the cTK plasmid in this protocol, we include assays for evaluating the function and specificity of the cTK reporter in apoptotic cells, such as assays for measuring the cell uptake of PET tracer in apoptotic cells, correlating doxorubicin (Dox)-induced cell apoptosis to cTK function recovery, and in vivo PET imaging of cancer cell apoptosis, and we also include corresponding data acquisition methods. The time to build the entire cTK reporter is ∼2-3 weeks. The selection of a stable cancer cell line takes ∼4-6 weeks. The time to implement assays regarding cTK function in apoptotic cells and the in vivo imaging varies depending on the experiment. The cyclization strategy described in this protocol can also be adapted to create other reporter systems for broad biomedical applications.
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Abstract
The coordination of cell proliferation and programmed death (apoptosis) is essential for normal physiology, and imbalance in these two opposing processes is implicated in various diseases. Objective and quantitative noninvasive imaging of apoptosis would significantly facilitate rapid screening as well as validation of therapeutic chemicals. Herein, we molecularly engineered an apoptosis switch-on PET-based cyclic herpes simplex virus type 1-thymidine kinase reporter (cTK266) containing a caspase-3 recognition domain as the switch. Translation of the reporter and protein splicing in healthy mammalian cells produce an inactive cyclic chimera. Upon apoptosis, caspase-3-specific cleavage of the circular product occurs, resulting in the restoration of the thymidine kinase activity, which can be detected in living cells and animals by noninvasive PET imaging. Our results showed the high sensitivity of this reporter in dynamic and quantitative imaging of apoptosis in living subjects. This reporter could be applied as a valuable tool for high-throughput functional screening of proapoptotic and antiapoptotic compounds in preclinical models in drug development, and monitoring the destination of therapeutic cells in clinical settings.
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Guo J, Guo N, Lang L, Kiesewetter DO, Xie Q, Li Q, Eden HS, Niu G, Chen X. (18)F-alfatide II and (18)F-FDG dual-tracer dynamic PET for parametric, early prediction of tumor response to therapy. J Nucl Med 2014; 55:154-60. [PMID: 24232871 PMCID: PMC4209961 DOI: 10.2967/jnumed.113.122069] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
UNLABELLED A single dynamic PET acquisition using multiple tracers administered closely in time could provide valuable complementary information about a tumor's status under quasiconstant conditions. This study aimed to investigate the utility of dual-tracer dynamic PET imaging with (18)F-alfatide II ((18)F-AlF-NOTA-E[PEG4-c(RGDfk)]2) and (18)F-FDG for parametric monitoring of tumor responses to therapy. METHODS We administered doxorubicin to one group of athymic nude mice with U87MG tumors and paclitaxel protein-bound particles to another group of mice with MDA-MB-435 tumors. To monitor therapeutic responses, we performed dual-tracer dynamic imaging, in sessions that lasted 90 min, starting with injection via the tail vein catheters with (18)F-alfatide II, followed 40 min later by (18)F-FDG. To achieve signal separation of the 2 tracers, we fit a 3-compartment reversible model to the time-activity curve of (18)F-alfatide II for the 40 min before (18)F-FDG injection and then extrapolated to 90 min. The (18)F-FDG tumor time-activity curve was isolated from the 90-min dual-tracer tumor time-activity curve by subtracting the fitted (18)F-alfatide II tumor time-activity curve. With separated tumor time-activity curves, the (18)F-alfatide II binding potential (Bp = k3/k4) and volume of distribution (VD) and (18)F-FDG influx rate ((K1 × k3)/(k2 + k3)) based on the Patlak method were calculated to validate the signal recovery in a comparison with 60-min single-tracer imaging and to monitor therapeutic response. RESULTS The transport and binding rate parameters K1-k3 of (18)F-alfatide II, calculated from the first 40 min of the dual-tracer dynamic scan, as well as Bp and VD correlated well with the parameters from the 60-min single-tracer scan (R(2) > 0.95). Compared with the results of single-tracer PET imaging, (18)F-FDG tumor uptake and influx were recovered well from dual-tracer imaging. On doxorubicin treatment, whereas no significant changes in static tracer uptake values of (18)F-alfatide II or (18)F-FDG were observed, both (18)F-alfatide II Bp and (18)F-FDG influx from kinetic analysis in tumors showed significant decreases. For therapy of MDA-MB-435 tumors with paclitaxel protein-bound particles, a significant decrease was observed only with (18)F-alfatide II Bp value from kinetic analysis but not (18)F-FDG influx. CONCLUSION The parameters fitted with compartmental modeling from the dual-tracer dynamic imaging are consistent with those from single-tracer imaging, substantiating the feasibility of this methodology. Even though no significant differences in tumor size were found until 5 d after doxorubicin treatment started, at day 3 there were already substantial differences in (18)F-alfatide II Bp and (18)F-FDG influx rate. Dual-tracer imaging can measure (18)F-alfatide II Bp value and (18)F-FDG influx simultaneously to evaluate tumor angiogenesis and metabolism. Such changes are known to precede anatomic changes, and thus parametric imaging may offer the promise of early prediction of therapy response.
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Affiliation(s)
- Jinxia Guo
- Department of Biomedical Engineering and Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology, Wuhan, Hubei, China
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
- Center for Molecular Imaging and Translational Medicine (CMITM), School of Public Health, Xiamen University, Xiamen, China
| | - Ning Guo
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
- Center for Advanced Medical Imaging Science, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Cambridge, MA
| | - Lixin Lang
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
| | - Dale O. Kiesewetter
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
| | - Qingguo Xie
- Department of Biomedical Engineering and Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Quanzheng Li
- Center for Advanced Medical Imaging Science, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Cambridge, MA
| | - Henry S. Eden
- Intramural Research Program (IRP), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
| | - Gang Niu
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
| | - Xiaoyuan Chen
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health (NIBIB), Bethesda, Maryland
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Niu G, Chen X. Molecular imaging with activatable reporter systems. Am J Cancer Res 2012; 2:413-23. [PMID: 22539937 PMCID: PMC3337733 DOI: 10.7150/thno.3940] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2011] [Accepted: 02/08/2012] [Indexed: 12/28/2022] Open
Abstract
Molecular imaging is a newly emerged multiple disciplinary field that aims to visualize, characterize and quantitatively measure biological processes at cellular and molecular levels in humans and other living systems. A reporter gene is a piece of DNA encoding reporter protein, which presents as a readily measurable phenotype that can be distinguished easily from the background of endogenous protein. After being transferred into cells of organ systems (transgenes), the reporter gene can be utilized to visualize transcriptional and posttranscriptional regulation of gene expression, protein-protein interactions, or trafficking of proteins or cells in living subjects. Herein, we review previous classification of reporter genes and regroup the reporter gene based imaging as basic, inducible and activatable, based on the regulation of reporter gene transcription and post-translational modification of reporter proteins. We then focus on activatable reporters, in which the signal can be activated at the posttranslational level for visualizing protein-protein interactions, protein phosphorylation or tertiary structure changes. The applications of several types of activatable reporters will also be summarized. We conclude that activatable reporter imaging can benefit both basic biomedical research and drug development.
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Effect of Animal Condition and Fluvoxamine on the Result of [(18)F]N-3-Fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) Nortropane ([(18)F]FP-CIT) PET Study in Mice. Nucl Med Mol Imaging 2012; 46:27-33. [PMID: 24900029 DOI: 10.1007/s13139-011-0117-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 10/26/2011] [Accepted: 11/02/2011] [Indexed: 10/15/2022] Open
Abstract
PURPOSE PET (positron emission tomography) is a noninvasive imaging technique, visualizing biological aspects in vivo. In animal models, the result of PET study can be affected more prominently than in humans by the animal conditions or drug pretreatment. We assessed the effects of anesthesia, body temperature, and pretreatment with selective serotonin reuptake inhibitor on the results of [(18)F]N-3-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropane ([(18)F]FP-CIT) PET in mice. METHODS [(18)F]FP-CIT PET of C57BL/6 mice was performed in three different conditions: (1) anesthesia (isoflurane) with active warming (38°C) as a reference; (2) no anesthesia or warming; (3) anesthesia without warming at room temperature. Additional groups of mice pretreated with escalating doses of fluvoxamine (5, 20, 40, 80 mg/kg) were imaged in condition (1). The time activity curve and standardized uptake value of the striatum, cerebral cortex, and bone were compared among these conditions. RESULTS In all conditions, radioactivities of the striatum and cortex tended to form a plateau after rapid uptake and washout, but that of bone tended to increase gradually. When anesthetized without any warming, all the mice developed hypothermia and showed reduced bone uptake with slightly increased striatal and cortical uptakes compared to the reference condition. In conditions without anesthesia, striatal and cortical uptakes were reduced, whereas the bone uptake showed no change. Pretreatment with fluvoxamine increased the striatal uptake and striatal specific to cortical non-specific uptake ratio, whereas the bone uptake was reduced. CONCLUSION Anesthesia, body temperature, and fluvoxamine affect the result of [(18)F]FP-CIT PET in mice by altering striatal and bone uptakes.
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Abstract
Noninvasive in vivo imaging of lymphatic vessels and lymphatic nodes is expected to fulfill the purpose of analyzing lymphatic vessels and their function, understanding molecular mechanisms of lymphangiogenesis and lymphatic spread of tumors, and utilizing lymphatic molecular markers as a prognostic or diagnostic indicator. In this review, we provide a comprehensive summary of in vivo imaging modalities for detecting lymphatic vessels, lymphatic drainage, and lymphatic nodes, which include conventional lymphatic imaging techniques such as dyes and radionuclide scintigraphy as well as novel techniques for lymphatic imaging such as optical imaging, computed tomography, magnetic resonance imaging, ultrasound, positron emission tomography using lymphatic biomarkers, photoacoustic imaging, and combinations of multiple modalities. The field of lymphatic imaging is ever evolving, and technological advances, combined with the development of new contrast agents, continue to improve the research of lymphatic vascular system in health and disease states as well as to improve the accuracy of diagnosis in the relevant diseases.
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Affiliation(s)
- Fan Zhang
- Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD 20892, USA
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Price PM, Green MM. Positron emission tomography imaging approaches for external beam radiation therapies: current status and future developments. Br J Radiol 2011; 84 Spec No 1:S19-34. [PMID: 21427180 DOI: 10.1259/bjr/21263014] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In an era in which it is possible to deliver radiation with high precision, there is a heightened need for enhanced imaging capabilities to improve tumour localisation for diagnostic, planning and delivery purposes. This is necessary to increase the accuracy and overall efficacy of all types of external beam radiotherapy (RT), including particle therapies. Positron emission tomography (PET) has the potential to fulfil this need by imaging fundamental aspects of tumour biology. The key areas in which PET may support the RT process include improving disease diagnosis and staging; assisting tumour volume delineation; defining tumour phenotype or biological tumour volume; assessment of treatment response; and in-beam monitoring of radiation dosimetry. The role of PET and its current developmental status in these key areas are overviewed in this review, highlighting the advantages and drawbacks.
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Affiliation(s)
- P M Price
- Department of Academic Radiation Oncology, The University of Manchester, The Christie Hospital NHS Foundation Trust, Manchester, UK.
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Mercier F, Paris J, Kaisin G, Thonon D, Flagothier J, Teller N, Lemaire C, Luxen A. General method for labeling siRNA by click chemistry with fluorine-18 for the purpose of PET imaging. Bioconjug Chem 2010; 22:108-14. [PMID: 21174402 DOI: 10.1021/bc100263y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click-type reaction, was used to label a double-stranded oligonucleotide (siRNA) with fluorine-18. An alkyne solid support CPG for the preparation of monostranded oligonucleotides functionalized with alkyne has been developed. Two complementary azide labeling agents (1-(azidomethyl)-4-[(18)F]fluorobenzene) and 1-azido-4-(3-[(18)F]fluoropropoxy)benzene have been produced with 41% and 35% radiochemical yields (decay-corrected), respectively. After annealing with the complementary strand, the siRNA was directly labeled by click chemistry with [(18)F]fluoroazide to produce the [(18)F]-radiolabeled siRNA with excellent radiochemical yield and purity.
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Affiliation(s)
- Frédéric Mercier
- Cyclotron Research Center, Université de Liège, Sart-Tilman B.30, B-4000 Liège, Belgium
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Lu S, Pike VW. Synthesis of [F]Xenon Difluoride as a Radiolabeling Reagent from [F]Fluoride Ion in a Micro-reactor and at Production Scale. J Fluor Chem 2010; 131:1032-1038. [PMID: 20871806 PMCID: PMC2944032 DOI: 10.1016/j.jfluchem.2010.07.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
[(18)F]Xenon difluoride ([(18)F]XeF(2)), was produced by treating xenon difluoride with cyclotron-produced [(18)F]fluoride ion to provide a potentially useful agent for labeling novel radiotracers with fluorine-18 (t(1/2) = 109.7 min) for imaging applications with positron emission tomography, Firstly, the effects of various reaction parameters, for example, vessel material, solvent, cation and base on this process were studied at room temperature. Glass vials facilitated the reaction more readily than polypropylene vials. The reaction was less efficient in acetonitrile than in dichloromethane. Cs(+) or K(+) with or without the cryptand, K 2.2.2, was acceptable as counter cation. The production of [(18)F]XeF(2) was retarded by K(2)CO(3), suggesting that generation of hydrogen fluoride in the reaction milieu promoted the incorporation of fluorine-18 into xenon difluoride. Secondly, the effect of temperature was studied using a microfluidic platform in which [(18)F]XeF(2) was produced in acetonitrile at elevated temperature (≥ 85 °C) over 94 s. These results enabled us to develop a method for obtaining [(18)F]XeF(2) on a production scale (up to 25 mCi) through reaction of [(18)F]fluoride ion with xenon difluoride in acetonitrile at 90 °C for 10 min. [(18)F]XeF(2) was separated from the reaction mixture by distillation at 110 °C. Furthermore, [(18)F]XeF(2) was shown to be reactive towards substrates, such as 1-((trimethylsilyl)oxy)cyclohexene and fluorene.
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Affiliation(s)
- Shuiyu Lu
- PET Radiopharmaceutical Sciences Section, Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Room B3 C346, Bethesda, MD 20892-1003, USA
| | - Victor W. Pike
- PET Radiopharmaceutical Sciences Section, Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, 10 Center Drive, Room B3 C346, Bethesda, MD 20892-1003, USA
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Niu G, Chen X. From protein–protein interaction to therapy response: Molecular imaging of heat shock proteins. Eur J Radiol 2009; 70:294-304. [DOI: 10.1016/j.ejrad.2009.01.052] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2009] [Accepted: 01/14/2009] [Indexed: 12/11/2022]
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Abstract
Angiogenesis is a highly-controlled process that is dependent on the intricate balance of both promoting and inhibiting factors, involved in various physiological and pathological processes. A comprehensive understanding of the molecular mechanisms that regulate angiogenesis has resulted in the design of new and more effective therapeutic strategies. Due to insufficient sensitivity to detect therapeutic effects by using standard clinical endpoints or by looking for physiological improvement, a multitude of imaging techniques have been developed to assess tissue vasculature on the structural, functional and molecular level. Imaging is expected to provide a novel approach to noninvasively monitor angiogenesis, to optimize the dose of new antiangiogenic agents and to assess the efficacy of therapies directed at modulation of the angiogenic process. All these methods have been successfully used preclinically and will hopefully aid in antiangiogenic drug development in animal studies. In this review article, the application of PET in angiogenesis imaging at both functional and molecular level will be discussed. For PET imaging of angiogenesis related molecular markers, we emphasize integrin alpha(v)beta(3), VEGF/VEGFR, and MMPs.
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Wieder HA, Herrmann K, Ott K, Krause BJ. 18F-FDG-PET zur Therapieverlaufskontrolle beim Ösophaguskarzinom. Radiologe 2007; 47:110-4. [PMID: 17225182 DOI: 10.1007/s00117-006-1461-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PET imaging with the glucose analog fluorodeoxyglucose (FDG-PET) has been evaluated in several studies to monitor tumor response in patients undergoing chemo- and radiotherapy. The clinical value of FDG-PET for differentiation of residual tumor and therapy induced fibrosis has been documented for esophageal cancer. Furthermore, there are now several reports suggesting that quantitative assessment of therapy induced changes in tumor FDG-uptake may allow prediction of tumor response and patient outcome very early in the course of therapy. This suggests that FDG-PET may be used to identify non-responders early during neoadjuvant chemoradiotherapy allowing for early modifications of the treatment protocol.
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Affiliation(s)
- H A Wieder
- Institut für Röntgendiagnostik, Klinikum rechts der Isar der Technischen Universität München.
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Lendvai G, Velikyan I, Bergström M, Estrada S, Laryea D, Välilä M, Salomäki S, Långström B, Roivainen A. Biodistribution of 68Ga-labelled phosphodiester, phosphorothioate, and 2'-O-methyl phosphodiester oligonucleotides in normal rats. Eur J Pharm Sci 2006; 26:26-38. [PMID: 15941654 DOI: 10.1016/j.ejps.2005.04.017] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Accepted: 04/11/2005] [Indexed: 10/25/2022]
Abstract
Antisense oligonucleotides may hybridise with high selectivity to mRNA sequences allowing monitoring of gene expression or inhibition of the manifestation of altered genes inducing diseases. As part of the development of positron emission tomography methods, 17-mer antisense phosphodiester (PO), phosphorothioate (PS) and 2'-O-methyl phosphodiester (OMe) oligonucleotides specific for point mutationally activated human K-ras oncogene were labelled with 68Ga radionuclide via a chelator coupled to the probe. Hybridisation in solution and non-denaturing polyacrylamide gel electrophoresis (PAGE) with a subsequent exposure of the gels was performed to verify the hybridisation ability after labelling. The biodistribution was studied in male Sprague-Dawley rats by injecting 2MBq of 68Ga-oligonucleotides via the tail vein and measuring the organ radioactivity concentration after 20, 60 and 120 min or using whole-body autoradiography with 10 MBq 68Ga-oligonucleotide and 20 min incubation time. Control experiments were performed with 68GaCl3 and 68Ga-chelator complex. The results revealed that 68Ga-labelling did not change the hybridisation abilities of the oligonucleotides. The biodistribution pattern depended on the nature of the oligonucleotide backbone. Bone marrow, kidney, liver, spleen and urinary bladder were the five organs of highest uptake with each oligonucleotide. The PO accumulated highly in the liver, whereas high kidney uptake dominated the PS and OMe patterns. Intact PS and OMe were detected in plasma samples taken 20 and 60 min after injection. This study supplies a base for the further development of 68Ga-labelled oligonucleotides as pharmacokinetic tools and a potential future use for in vivo imaging of gene expression.
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Affiliation(s)
- Gabor Lendvai
- Uppsala Imanet, S-751 09 Uppsala, PO Box 967, Sweden.
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Abbey CK, Borowsky AD, Gregg JP, Cardiff RD, Cherry SR. Preclinical imaging of mammary intraepithelial neoplasia with positron emission tomography. J Mammary Gland Biol Neoplasia 2006; 11:137-49. [PMID: 17091397 DOI: 10.1007/s10911-006-9020-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Small-animal imaging with positron emission tomography (PET) has become a valuable tool for evaluating preclinical models of breast cancer and other diseases. In this review, we examine a number of issues related to preclinical imaging studies with PET, using transgenic models of ductal carcinoma in situ and metastasis as specific examples. We discuss imaging components such as reconstruction, normalization, and extraction of quantitative parameters. We also analyze the effect of longitudinal correlations on cohort size and present some simple statistical techniques for determining cohort sizes that may be helpful in designing preclinical imaging studies. We describe studies that are greatly facilitated by access to non-invasive imaging data including a study involving multiple endpoints and another investigating metastasis. We conclude with a brief survey of emerging approaches in small-animal PET imaging.
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Affiliation(s)
- Craig K Abbey
- Department of Biomedical Engineering, University of California, Davis, CA 95616, USA.
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Peng X, Zhang A, Kula NS, Baldessarini RJ, Neumeyer JL. Synthesis and amine transporter affinities of novel phenyltropane derivatives as potential positron emission tomography (PET) imaging agents. Bioorg Med Chem Lett 2005; 14:5635-9. [PMID: 15482938 DOI: 10.1016/j.bmcl.2004.08.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Revised: 08/19/2004] [Accepted: 08/19/2004] [Indexed: 12/12/2022]
Abstract
A series of novel fluoroalkyl-containing tropane derivatives (6-8, 10-14, 17, and 18) were synthesized from cocaine. Novel compounds were evaluated for affinity and selectivity in competitive radioligand binding assays selective for cerebral serotonin (5-HT), dopamine (DA), and norepinephrine (NE) transporters (SERT, DAT, and NET). The nortropane-fluoroalkyl esters (7, 10, 11) were most potent for SERT (K(i): 0.18, 0.24, and 0.30 nM, respectively). Tosylate esters 17 and 18, synthesized as precursors for [(18)F]-labeled, Positron Emission Tomography (PET) imaging agents, also showed high affinity for DAT.
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Affiliation(s)
- Xuemei Peng
- Medicinal Chemistry Laboratory, Alcohol and Drug Abuse Research Center, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, MA 02478-9106, USA
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Jones T. The enabling technologies needed for PET-based molecular imaging to support drug development. DRUG DISCOVERY TODAY. TECHNOLOGIES 2005; 2:305-309. [PMID: 24982005 DOI: 10.1016/j.ddtec.2005.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
It is commonly believed that all that is required to effect PET based molecular imaging to support drug development is a cyclotron and a PET scanner. This review itemises the many additional technologies needed to enable the full exploitation of PET for pharmacodynamic and pharmacokinetic measurements of normal and diseased tissues. There are ongoing developments in each area which when integrated add up to significant advances in the quality and value of the resulting data.:
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Affiliation(s)
- Terry Jones
- University of Manchester Wolfson Molecular Imaging Centre, Christie Hospital, 27 Palatine Road, Manchester, UK M20 3LJ.
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20
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Abstract
This contribution presents clinical and technical aspects of combining positron emission tomography (PET) and computed tomography (CT) for patients with colorectal tumors and characterization of unclear liver foci. In which manner and for which patients combined PET/CT is superior to PET or CT alone is also discussed. PET/CT can fulfil most prerequisites for imaging in pre- and postoperative management of patients with colorectal tumors and best meets the desire for optimal imaging procedures. Some of the disadvantages encountered in frequently employed CT can be overcome by the combination of PET and CT while increasing both sensitivity in detecting lesions and specificity in their characterization. Questions regarding treatment response offer an opportunity for devising novel study concepts and initiating research on new PET tracers. Although few publications are available, we are of the opinion that the combination of functional and anatomical imaging provided by PET/CT can improve both preoperative management and aftercare. To this end, however, optimum cooperation between practitioners of nuclear medicine and radiology is imperative.
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Affiliation(s)
- J Stollfuss
- Institut für Röntgendiagnostik, Klinikum rechts der Isar der TU München.
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21
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Annovazzi A, Peeters M, Maenhout A, Signore A, Dierckx R, Van De Wiele C. 18-fluorodeoxyglucose positron emission tomography in nonendocrine neoplastic disorders of the gastrointestinal tract. Gastroenterology 2003; 125:1235-45. [PMID: 14517805 DOI: 10.1016/s0016-5085(03)01208-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abstract
In the last 20 years, a number of non-invasive spatial mapping techniques have been demonstrated to provide powerful insights into the operation of the brain during task performance. These are, in order of their emergence as robust technologies: positron emission tomography, source localization with EEG and MEG, and functional magnetic resonance imaging. The imaging neuroscience study areas represented in this volume use the first or last of these - PET and fMRI. The physical principles underlying both of these techniques are outlined, and the important assumptions and limitations are made explicit. The range of applications for each is briefly indicated.
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Affiliation(s)
- Robert Turner
- Wellcome Department of Imaging Neuroscience, Institute of Neurology, University College London, UK
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Affiliation(s)
- T Jones
- Wolfson Molecular Imaging Centre, Christie Hospital NHS Trust, Wilmslow Road, Manchester M20 4BX, UK
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Van den Abbeele AD, Badawi RD. Use of positron emission tomography in oncology and its potential role to assess response to imatinib mesylate therapy in gastrointestinal stromal tumors (GISTs). Eur J Cancer 2002; 38 Suppl 5:S60-5. [PMID: 12528774 DOI: 10.1016/s0959-8049(02)80604-9] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The reliability of established anatomical imaging techniques, such as computed tomography (CT) and magnetic resonance imaging (MRI), is compromised in following response to certain types of treatment if metabolic improvement occurs before morphologic change is apparent. Thus, traditional imaging techniques cannot discriminate early tumor response because they are based on purely visual structural assessments. Recently, the use of positron emission tomography (PET), most commonly employing the radiotracer 18F-fluoro-2-deoxy-D-glucose (FDG), has been shown to improve the assessment of tumor behavior by highlighting early functional changes in tumor glucose metabolism that appear to correlate closely with metabolic tumor response to imatinib mesylate. Like CT and MRI, PET can identify an abnormal mass; its improvement over these techniques lies in its ability to differentiate active tumor from necrosing tissue, malignant from benign tissue, and recurrent tumor from scar tissue. Understanding and using this tool should improve our ability to accurately follow response in GIST patients treated with imatinib mesylate, and permit this new therapeutic approach to be used optimally with accurate follow-up assessments and informed therapeutic decision-making.
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25
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Abstract
Positron emission tomography (PET) using (18)F-fluorodeoxyglucose (FDG) is increasingly used in the diagnostic management of colorectal cancer patients. It provides a highly sensitive and specific diagnosis which is entirely based upon alterations of the glucose metabolism found in malignant tissues. The information provided by FDG-PET is independent of the underlying structural characteristics of the lesions and, therefore, it is essentially complementary to the available structural imaging modalities such as CT, MRI and (endoscopic) ultrasound. Several studies have now been performed on the use of FDG-PET in colorectal adenocarcinoma for primary pre-operative staging, for diagnosis and (re)staging of recurrent disease, for localization and staging of occult recurrent disease, and for the assessment of the metabolic effects of chemotherapy and radiotherapy. This chapter aims to clarify some fundamental issues of both detection device and radiotracer, the proven indications for FDG-PET, the strength and limitations of the technique, and how its implementation would affect patient management.
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Affiliation(s)
- Patrick Flamen
- Department of Nuclear Medicine, University Hospital Gasthuisberg, Leuven, Belgium
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26
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Tavitian B, Marzabal S, Boutet V, Kühnast B, Terrazzino S, Moynier M, Dollé F, Deverre JR, Thierry AR. Characterization of a synthetic anionic vector for oligonucleotide delivery using in vivo whole body dynamic imaging. Pharm Res 2002; 19:367-76. [PMID: 12033366 DOI: 10.1023/a:1015133205457] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE To compare the pharmacokinetics and bioavailability of an oligonucleotide delivered in a free form or using cationic or anionic synthetic carrier systems. METHODS Whole body dynamic quantitative imaging and metabolism of a HIV antisense oligonucleotide intravenously administered either free or incorporated into synthetic carriers were compared in baboons. using non invasive positron emission tomography and an enzyme-based competitive hybridization assay, respectively. RESULTS In its free form, the oligonucleotide showed high liver and kidney concentration, rapid plasmatic degradation and elimination from the body. Use of a cationic vector slightly protected the oligonucleotide against degradation and enhanced uptake by the reticulo-endothelial system. In contrast, the anionic vector dramatically enhanced the uptake in several organs, including the lungs, spleen and brain, with a prolonged accumulation of radioactivity in the brain. Using this vector, intact oligonucleotide was detected in plasma for up to two hours after injection. and the T 1/2beta and distribution volume increased by 4- and 7-fold, respectively. No evidence of toxicity was found after a single dose administration. CONCLUSIONS The anionic vector improves significantly the bioavailability and the pharmacokinetics of the oligonucleotide, and is a promising delivery system for in vivo administration of therapeutic nucleic acids.
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Karimi F, Långström B. Synthesis of 3-[(2S)-azetidin-2-ylmethoxy]-5-[11C]-methylpyridine, an analogue of A-85380, via a Stille coupling. J Labelled Comp Radiopharm 2002. [DOI: 10.1002/jlcr.569] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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28
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Kuhnast B, Dolle F, Tavitian B. Fluorine-18 labeling of peptide nucleic acids. J Labelled Comp Radiopharm 2002. [DOI: 10.1002/jlcr.522] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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29
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Gu XH, Zong R, Kula NS, Baldessarini RJ, Neumeyer JL. Synthesis and biological evaluation of a series of novel N- or O-fluoroalkyl derivatives of tropane: potential positron emission tomography (PET) imaging agents for the dopamine transporter. Bioorg Med Chem Lett 2001; 11:3049-53. [PMID: 11714608 DOI: 10.1016/s0960-894x(01)00626-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A series of novel fluoroalkyl-containing tropane derivatives was synthesized, and their binding affinities for the dopamine transporter (DAT), serotonin transporter (SERT), and norepinephrine transporter (NET) were determined via competitive binding assays. Among these derivatives, the fluoropropyl ester of beta-CIT (19), the fluoroethyl ester of beta-CIT (20), the N-fluoropropyl derivative of beta-CBT (12), and the fluoropropyl ester of beta-CMT (18) displayed higher affinity and greater selectivity for the DAT versus SERT and NET than FP-CIT, which indicates that they are attractive candidates for the development of (18)F-labeled PET imaging agents for the DAT.
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Affiliation(s)
- X H Gu
- Medicinal Chemistry Laboratory, Alcohol and Drug Abuse Research Center, Belmont, MA 02478-9106, USA
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Abstract
During the past ten years, positron emission tomography (PET) has been increasingly developed for imaging and quantifying molecular mechanisms in oncology. The technique uses radionuclides to label molecules, which can then be imaged in man. The inherent sensitivity and specificity of PET is unrivalled because it can image molecular interactions and pathways, providing quantitative kinetic information down to the subpicomolar level. This technology has the potential to answer a large number of important clinical questions in translational research in oncology. However, the challenges in the methodology are substantial. Molecular imaging has the potential to assist in the optimization of molecular-based targeted therapies in cancer and to investigate the function of the genome.
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Affiliation(s)
- P Price
- Molecular Imaging Centre, Academic Department of Radiation Oncology, University of Manchester, UK.
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31
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Abstract
Among the several imaging technologies applied to in vivo studies of research animals, positron emission tomography (PET) is a nuclear imaging technique that permits the spatial and temporal distribution of compounds labeled with a positron-emitting radionuclide to be determined noninvasively. It can be viewed as an in vivo analog of classic autoradiographic methods. Many different positron-labeled compounds have been synthesized as tracers that target a range of specific markers or pathways. These tracers permit the measurement of quantities of biological interest ranging from glucose metabolism to gene expression. PET has been extensively used in imaging studies of larger research animals such as dogs and nonhuman primates. Now, using newly developed high-resolution dedicated animal PET scanners, these types of studies can be performed in small laboratory animals such as mice and rats. The entire whole-body biodistribution kinetics can be determined in a single imaging study in a single animal. This technique should enable statistically significant biodistribution data to be obtained from a handful of animals, compared with the tens or hundreds of animals that might be required for a similar study by autoradiography. PET also enables repeat studies in a single subject, facilitating longitudinal study designs and permitting each animal to serve as its own control in experiments designed to evaluate the effects of a particular interventional strategy. This paper provides a basic overview of the methodology of PET imaging, a discussion of the advantages and drawbacks of PET as a tool in animal research, a description of the latest generation of dedicated animal PET scanners, and a review of a few of the many applications of PET in animal research to date.
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Affiliation(s)
- S R Cherry
- Crump Institute for Molecular Imaging, Department of Molecular and Medical Pharmacology, University of California, Los Angeles School of Medicine, Los Angeles, California, USA.
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32
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Dutka DP, Camici PG. The contribution of positron emission tomography to the study of ischemic heart failure. Prog Cardiovasc Dis 2001; 43:399-418. [PMID: 11251127 DOI: 10.1053/pcad.2001.20673] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cardiac imaging with positron emission tomography offers unrivaled sensitivity and specificity to probe cardiovascular physiology in health and disease. The use of positron emission tomography to noninvasively measure regional myocardial blood flow and assess myocardial viability in patients with ventricular dysfunction and coronary artery disease has contributed greatly to our understanding of the pathophysiology of ischemic heart failure. The advances and the need for further studies to establish both the natural history of such ventricular dysfunction and the role of coronary revascularization are discussed.
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Affiliation(s)
- D P Dutka
- MRC Clinical Sciences Centre, Imperial College School of Medicine, London, England
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33
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Chapter 26. PET ligands for assessing receptor occupancy in vivo. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2001. [DOI: 10.1016/s0065-7743(01)36066-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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34
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Hall CS, Marsh JN, Scott MJ, Gaffney PJ, Wickline SA, Lanza GM. Time evolution of enhanced ultrasonic reflection using a fibrin-targeted nanoparticulate contrast agent. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2000; 108:3049-57. [PMID: 11144597 DOI: 10.1121/1.1322566] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Complex molecular signaling heralds the early stages of pathologies such as angiogenesis, inflammation, unstable atherosclerotic plaques, and areas of remote thrombi. In previous studies, acoustic enhancement of blood clot morphology was demonstrated with the use of a nongaseous, fibrin-targeted acoustic nanoparticle emulsion delivered to areas of thrombosis both in vitro and in vivo. In this study, a system was designed and constructed that allows visualization of the evolution of acoustic contrast enhancement. To evaluate the system, two targets were examined: avidin-complexed nitrocellulose membrane and human plasma clots. The time evolution of enhancement was visualized in 10-min increments for 1 h. A monotonic increase was observed in ultrasonic reflection enhancement from specially treated nitrocellulose membranes for targeted emulsions containing perfluorooctylbromide (1.30+/-0.3 dB) and for perfluorooctane (2.64+/-0.5 dB) within the first 60 min of imaging. In comparison, the inherently nonechogenic plasma clots showed a substantial increase of 12.0+/-0.9 dB when targeted with a perfluoro-octane emulsion. This study demonstrates the concept of molecular imaging and provides the first quantifiable time-evolution report of the binding of a site-targeted ultrasonic contrast agent. Moreover, with the incorporation of specific drug treatments into the nanoparticulate contrast agent, ultrasonic molecular imaging may yield reliable detection and quantification of nascent pathologies and facilitate targeted drug therapy.
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Affiliation(s)
- C S Hall
- Washington University School of Medicine, St. Louis, Missouri 63110, USA
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35
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Abstract
The origins of positron emission tomography (PET) date back 70 years. Since the 1970s, however, its use has increased exponentially in the fields of neurology, cardiology and oncology. [18F]-Fluorodeoxyglucose (FDG) whole-body scanning is by far the most widely utilised and recognised application of PET in oncology. However, PET is a very versatile and powerful imaging modality capable of helping bridge the gap between the laboratory and the clinic. This article reviews the history and current applications of PET in oncology and then explores some of the newer applications and potential future uses of this versatile technology particularly in the area of cancer research.
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Affiliation(s)
- H Anderson
- CRC PET Oncology Group, MRC Cyclotron Unit, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, W12 0NN, London, UK
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36
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BESRET LAURENT, KENDALL ALISA, DUNNETT STEPHENB. Aspects of PET imaging relevant to the assessment of striatal transplantation in Huntington's disease. J Anat 2000; 196 ( Pt 4):597-607. [PMID: 10923990 PMCID: PMC1468100 DOI: 10.1046/j.1469-7580.2000.19640597.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proper assessment of outcome in clinical trials of neural transplantation requires both biochemical and imaging indices of graft survival, and behavioural and physiological indices of graft function. For transplantation in Huntington's disease, a variety of ligands that are selective for striatal degeneration and graft-derived replacement are available, notably ligands of dopaminergic receptors on striatal neurons. However, the validity of such ligands is potentially compromised by adjunctive drug therapies (e.g. neuroleptics) given to patients in the course of normal clinical care. We review the present state of experimental and clinical understanding of the selectivity of available ligands for striatal imaging, their interaction with other drug treatments, and strategies for refining valid assessment protocols in patients.
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Affiliation(s)
| | | | - STEPHEN B.
DUNNETT
- Centre for Brain Repair, University of Cambridge, UK
- Correspondence to Dr Stephen B. Dunnett, Department of Biosciences, Preclinical Sciences building, Cardiff University, Cardiff, UK. Tel. 01222 875188; fax. 01223 874117; email
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Pike VW, Law MP, Osman S, Davenport RJ, Rimoldi O, Giardinà D, Camici PG. Selection, design and evaluation of new radioligands for PET studies of cardiac adrenoceptors. PHARMACEUTICA ACTA HELVETIAE 2000; 74:191-200. [PMID: 10812957 DOI: 10.1016/s0031-6865(99)00032-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Changes in the numbers of human cardiac adrenoceptors (ARs) are associated with various diseases, such as myocardial ischemia, congestive heart failure, cardiomyopathy and hypertension. There is a clear need for capability to assess human cardiac ARs directly in vivo. Positron emission tomography (PET) is an imaging technique that provides this possibility, if effective radioligands can be developed for the targeted ARs. Here, the status of myocardial AR radioligand development for PET is described. Currently, there exist effective radioligands for imaging beta-ARs in human myocardium. One of these, [11C](S)-CGP 12177, is applied extensively to clinical research with PET, sometimes with other tracers of other aspects of the noradrenalin system. Alternative radioligands are in development for beta-ARs, including beta 1-selective radioligands. A promising radioligand for imaging myocardial alpha 1-ARs, [11C]GB67, is now being evaluated in human PET experiments.
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Affiliation(s)
- V W Pike
- MRC Cyclotron Unit, Imperial College School of Medicine, Hammersmith Hospital, London, UK.
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Goethals P, Volkaert A, Vandewielle C, Dierckx R, Lameire N. 55Co-EDTA for renal imaging using positron emission tomography (PET): a feasibility study. Nucl Med Biol 2000; 27:77-81. [PMID: 10755649 DOI: 10.1016/s0969-8051(99)00077-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The feasibility of imaging renal function with 55Co-ethylene diamine tetraacetic acid (EDTA) and dynamic positron emission tomography was investigated. A group of normal Wistar rats was injected intravenously with 55Co-EDTA and underwent dynamic positron emission tomography (PET) imaging in order to study the biodistribution. The time-activity curves of the heart (blood pool), both kidneys, liver, and bladder were observed. In two animals, blood and urinary clearances of 55Co-EDTA were compared with those for 51Cr-EDTA. In one animal, unilateral reduction in kidney function was induced and the right/left ratio for the kidneys was determined. The time-activity curves showed that 55Co-EDTA cleared rapidly from the blood pool (heart), whereas prompt and high target-to-background ratios for both kidneys were obtained. The entire tracer was cleared from the renal parenchyma by urinary excretion and collection of the activity in the bladder. No specific activity uptake was noticed in any other organ or tissue. The clearances of 55Co-EDTA and 51Cr-EDTA in blood were not significantly different, showing that the nature of the M++ has no influence on the in vivo behavior of EDTA. 55Co can be produced easily by cyclotron irradiation and 55Co-EDTA is a promising physiological tracer for nephrological research using PET.
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Affiliation(s)
- P Goethals
- Institute for Nuclear Sciences, Gent, Flanders, Belgium.
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39
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Jones H, Mitra G, Parkinson D, Spinks T. A parallel implementation of the maximum likelihood method in positron emission tomography image reconstruction. Comput Stat Data Anal 1999. [DOI: 10.1016/s0167-9473(99)00040-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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40
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Burns HD, Hamill TG, Eng WS, Francis B, Fioravanti C, Gibson RE. Positron emission tomography neuroreceptor imaging as a tool in drug discovery, research and development. Curr Opin Chem Biol 1999; 3:388-94. [PMID: 10419855 DOI: 10.1016/s1367-5931(99)80059-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Improved communication and cooperation between research-driven drug companies and academic positron emission tomography (PET) centers, coupled with improvements in PET camera resolution, the availability of small animal PET cameras and a growing list of neuroreceptor-specific PET tracers, have all contributed to a substantial increase in the use and value of PET as a tool in central nervous system drug discovery and development.
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Affiliation(s)
- H D Burns
- Department of Pharmacology, Merck Research Laboratories, WP44C-2, Sumneytown Pike, West Point, PA 19438, USA.
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41
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Tavitian B, Terrazzino S, Kühnast B, Marzabal S, Stettler O, Dollé F, Deverre JR, Jobert A, Hinnen F, Bendriem B, Crouzel C, Di Giamberardino L. In vivo imaging of oligonucleotides with positron emission tomography. Nat Med 1998; 4:467-71. [PMID: 9546795 DOI: 10.1038/nm0498-467] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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42
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Germano G, Erel J, Lewin H, Kavanagh PB, Berman DS. Automatic quantitation of regional myocardial wall motion and thickening from gated technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography. J Am Coll Cardiol 1997; 30:1360-7. [PMID: 9350940 DOI: 10.1016/s0735-1097(97)00276-3] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES We developed an automatic quantitative algorithm for the measurement of regional myocardial wall motion and wall thickening from three-dimensional gated technetium-99m sestamibi myocardial perfusion single-photon emission computed tomographic images. BACKGROUND The algorithm measures the motion of the three-dimensional endocardial surface using a modification of the centerline method, as well as wall thickening using both geometry (gaussian fit) and partial volume (counts). METHODS The algorithm was tested using a "variable thickness" heart phantom, and the quantitative results were compared with visual segmental assessment of myocardial motion and thickening in 79 clinical patients with a wide range of ejection fractions (6% to 87%). RESULTS Phantom measurements of simulated motion and thickening were accurate regardless of the camera used (dual or triple detector), the angular span of reconstructed data (180 degrees or 360 degrees), the amount of motion (3 or 6 mm) or the amount of thickening (33%, 50% or 100%). Quantitative measurements of segmental motion and thickening in the patients were correlated with visual scores (r = 0.668, exact agreement 72.6%, kappa 0.433 and r = 0.550, exact agreement 74.7%, kappa 0.408, respectively). Significant inverse linear relations exist between the global (summed) visual motion score and the average quantitative motion, and between the global (summed) visual thickening score and the average quantitative thickening. Automatic quantitative ejection fraction measurements correlated extremely well with average quantitative motion (r = 0.929) and thickening (r = 0.959). CONCLUSIONS Our algorithm is accurate and may be the first automatic technique for the quantitative three-dimensional assessment of regional ventricular function in cardiology.
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Affiliation(s)
- G Germano
- Department of Medicine, Cedars-Sinai Research Institute, Cedars-Sinai Medical Center, University of California Los Angeles School of Medicine, 90048, USA.
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Price P. Is there a future for PET in oncology? EUROPEAN JOURNAL OF NUCLEAR MEDICINE 1997; 24:587-9. [PMID: 9235296 DOI: 10.1007/bf00841393] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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44
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Hicks RJ. Nuclear medicine techniques provide unique physiologic characterization of suspected and known soft tissue and bone sarcomas. ACTA ORTHOPAEDICA SCANDINAVICA. SUPPLEMENTUM 1997; 273:25-36. [PMID: 9057584 DOI: 10.1080/17453674.1997.11744699] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Primary bone and soft tissue tumors have a range of physiologic, biochemical and genetic characteristics which differentiate them from benign tumors and normal tissues. These "fingerprints" are amenable to noninvasive detection and quantification using nuclear medicine techniques. Functional characterization using radiotracers imaged using a gamma camera or positron emission tomography (PET) can provide unique but complementary information to that provided by anatomically-based imaging modalities such as plain radiography, computed tomography (CT) and magnetic resonance imaging (MRI). This is particularly important following therapy when residual mass lesions may cause a dilemma regarding the need for further treatment. Lack of understanding of the role of functional imaging has impeded more rational use of nuclear medicine in this field. This review addresses the role of nuclear medicine techniques in the primary evaluation, staging, and therapeutic monitoring of soft tissue and bone sarcomas. The potential of delivering targeted radiotherapy to these tumors with radiopharmaceuticals which exploit the unique pathophysiology of each individual malignant lesion is also addressed.
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Affiliation(s)
- R J Hicks
- Department of Nuclear Medicine, Peter MacCallum Cancer Institute, Melbourne, VIC, Australia
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