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Pei C, Baotong F, Zhiming Z, Haohui T, Shuangquan L, Xiaoli S, Peilin W, Xiaoming W, Xudong Z, Long W. NEMA NU-4 performance evaluation of a non-human primate animal PET. Phys Med Biol 2019; 64:105018. [PMID: 30947155 DOI: 10.1088/1361-6560/ab1614] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The Eplus-260 primate PET is an animal PET imaging system developed by the Institute of High Energy Physics, Chinese Academy of Sciences, which is designed to image non-human primates, especially the brain of large non-human primates. The system consists of 48 block detectors arranged in two 24-sided rings with a ring diameter of 263 mm and an axial extent of 64 mm. Each block detector is composed of a 16 × 16 cerium-doped lutetium-yttrium orthosilicate crystal array with a pixel size of 1.9 × 1.9 × 10 mm3. This article presents a performance evaluation of the PET scanner according to the National Electrical Manufacturers Association NU-4 2008 standards. All measurements were made for an energy window of 360-660 keV and a coincidence timing window of 2 ns. In terms of the FWHM, the FBP reconstructed spatial resolution results in all three directions at the radial position of 5 mm were better than or approached to 2 mm, and remained below 3.0 mm within the central 5 cm diameter of the FOV. The peak absolute sensitivity of the scanner was measured 1.80%. For a monkey-sized phantom, the scatter fraction was 34.2% and the peak noise equivalent count rate (NECR) was 26.5 kcps at 64.3 kBq/cc. The overall imaging capabilities of the scanner were also assessed using in vivo imaging study of a rhesus macaque. The performance measurements demonstrate that the Eplus-260 primate PET scanner has the potential ability to obtain good quality and high-contrast images for non-human primates, especially the brain of large non-human primates and could be considered as one technologically advanced dedicated non-human primate PET scanner available today.
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Affiliation(s)
- Chai Pei
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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Zhang Y, Liu F, Xiao H, Yao X, Li G, Choi SR, Ploessl K, Zha Z, Zhu L, Kung HF. Fluorine-18 labeled diphenyl sulfide derivatives for imaging serotonin transporter (SERT) in the brain. Nucl Med Biol 2018; 66:1-9. [PMID: 30096380 DOI: 10.1016/j.nucmedbio.2018.06.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 06/15/2018] [Accepted: 06/28/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVES Serotonin transporters (SERT) play an important role in controlling serotonin concentration in the synaptic cleft and in managing postsynaptic signal transduction. Inhibitors of SERT binding are well known as selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, sertraline, paroxetine, and escitalopram, that are commonly prescribed antidepressants. Positron emission tomography (PET) and single photon emission tomography (SPECT) imaging agents targeting SERT may be useful for studying its function and providing a tool for monitoring drug treatment. METHODS A series of novel 18F-labeled diphenyl sulfide derivatives were prepared and tested for their binding affinity. Among them, 2-((2-((dimethylamino)-methyl)-4-(2-(2-fluoroethoxy)ethoxy)phenyl)thio)aniline, 1, which showed excellent binding toward serotonin transporter (SERT) in the brain (Ki = 0.09 nM), was selected for further evaluation. An active OTs intermediate, 7, was treated with [18F]F-/K222 to provide [18F]1 in one step and in high radiochemical yields. This new SERT targeting agent was evaluated in rats by biodistribution studies and animal PET imaging studies. RESULTS The radiolabeling reaction led to the desired [18F]1. After HPLC purification no-carrier-added [18F]1 was obtained (radiochemical yield, 23-47% (n = 10,); radiochemical purity >99%; molar activity, 15-28 GBq/μmol). Biodistribution studies with [18F]1 showed good brain uptake (1.04% dose/g at 2 min post-injection), high uptake into the hypothalamus (1.55% dose/g at 30 min), and a high target-to-non-target (hypothalamus to cerebellum) ratio of 6.1 at 120 min post-injection. A PET imaging study in normal rats showed excellent uptake in the midbrain and thalamus regions known to be rich in SERT binding sites at 60 min after iv injection. Chasing experiment with escitalopram (iv, 2 mg/kg) in a rat at 60 min after iv injection caused a noticeable reduction in the regional radioactivity and the target-to-non-target ratio, suggesting binding by [18F]1 was highly specific and reversible for SERT binding sites in the brain. CONCLUSIONS A novel diphenyl sulfide derivative, [18F]1 for SERT imaging was successfully prepared and evaluated. Results suggest that this new chemical entity is targeting SERT binding sites in the brain, and it is a suitable candidate for future commercial development.
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Affiliation(s)
- Yan Zhang
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Futao Liu
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hao Xiao
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Xinyue Yao
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Genxun Li
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Seok Rye Choi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karl Ploessl
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Zhihao Zha
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals (College of Chemistry), Beijing Normal University, Ministry of Education, Beijing, 100875, China; Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China.
| | - Hank F Kung
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Liu F, Zhu L, Choi SR, Plössl K, Zha Z, Kung HF. Deuterium-substituted 2-(2′-((dimethylamino)methyl)-4′-[18
F](fluoropropoxy)phenylthio)benzenamine as a serotonin transporter imaging agent. J Labelled Comp Radiopharm 2018; 61:576-585. [DOI: 10.1002/jlcr.3626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/28/2018] [Accepted: 03/29/2018] [Indexed: 01/06/2023]
Affiliation(s)
- Futao Liu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education; Beijing Normal University; Beijing P. R. China
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education; Beijing Normal University; Beijing P. R. China
| | - Seok Rye Choi
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Karl Plössl
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Zhihao Zha
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
| | - Hank F. Kung
- Department of Radiology; University of Pennsylvania; Philadelphia Pennsylvania USA
- Five Eleven Pharma Inc; Philadelphia Pennsylvania USA
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Qiao H, Zhang Y, Wu Z, Zhu L, Choi SR, Ploessl K, Kung HF. One-step preparation of [(18)F]FPBM for PET imaging of serotonin transporter (SERT) in the brain. Nucl Med Biol 2016; 43:470-7. [PMID: 27236282 DOI: 10.1016/j.nucmedbio.2016.04.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/16/2016] [Accepted: 04/14/2016] [Indexed: 01/27/2023]
Abstract
Serotonin transporters (SERT) in the brain play an important role in normal brain function. Selective serotonin reuptake inhibitors such as fluoxetine, sertraline, paroxetine, escitalopram, etc., specifically target SERT binding in the brain. Development of SERT imaging agents may be useful for studying the function of SERT by in vivo imaging. A one-step preparation of [(18)F]FPBM, 2-(2'-(dimethylamino)methyl)-4'-(3-([(18)F]fluoropropoxy)phenylthio)benzenamine, for positron emission tomography (PET) imaging of SERT binding in the brain was achieved. An active OTs intermediate, 9, was reacted with [(18)F]F(-)/K222 to produce [(18)F]FPBM in one step and in high radiochemical yield. This labeling reaction was evaluated and optimized under different temperatures, bases, solvents, and varying amounts of precursor 9. The radiolabeling reaction led to the desired [(18)F]FPBM in one step and the crude product was purified by HPLC purification to give no-carrier-added [(18)F]FPBM (radiochemical yield, 24-33%, decay corrected; radiochemical purity >99%). PET imaging studies in normal monkeys (n=4) showed fast, pronounced uptakes in the midbrain and thalamus, regions known to be rich in SERT binding sites. A displacement experiment with escitalopram (5mg/kg iv injection at 30min after [(18)F]FPBM injection) showed a rapid and complete reversal of SERT binding, suggesting that binding by [(18)F]FPBM was highly specific and reversible. A one-step radiolabeling method coupled with HPLC purification for preparation of [(18)F]FPBM was developed. Imaging studies suggest that it is feasible to use this method to prepare [(18)F]FPBM for in vivo PET imaging of SERT binding in the brain.
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Affiliation(s)
- Hongwen Qiao
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing 100053, China; Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yan Zhang
- Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing, 100875, China
| | - Zehui Wu
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lin Zhu
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing, 100875, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Seok Rye Choi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karl Ploessl
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hank F Kung
- Beijing Institute for Brain Disorders, Capital Medical University, Beijing, 100069, China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Zhu L, Li G, Choi SR, Plössl K, Chan P, Qiao H, Zha Z, Kung HF. An improved preparation of [18F]FPBM: A potential serotonin transporter (SERT) imaging agent. Nucl Med Biol 2013; 40:974-9. [DOI: 10.1016/j.nucmedbio.2013.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 08/04/2013] [Indexed: 10/26/2022]
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Stehouwer JS, Goodman MM. 11C and18F PET radioligands for the serotonin transporter (SERT). J Labelled Comp Radiopharm 2013; 56:114-9. [DOI: 10.1002/jlcr.3011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 10/29/2012] [Accepted: 11/20/2012] [Indexed: 01/03/2023]
Affiliation(s)
- Jeffrey S. Stehouwer
- Center for Systems Imaging, Department of Radiology and Imaging Sciences; Emory University; Atlanta; GA; USA
| | - Mark M. Goodman
- Center for Systems Imaging, Department of Radiology and Imaging Sciences; Emory University; Atlanta; GA; USA
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Zheng P, Lieberman BP, Ploessl K, Lemoine L, Miller S, Kung HF. A new single-photon emission computed tomography (SPECT) imaging agent for serotonin transporters: [(125)I]Flip-IDAM, (2-((2-((dimethylamino)methyl)-4-iodophenyl)thio)phenyl)methanol. Bioorg Med Chem Lett 2013; 23:869-72. [PMID: 23265880 DOI: 10.1016/j.bmcl.2012.11.043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2012] [Revised: 11/07/2012] [Accepted: 11/12/2012] [Indexed: 11/18/2022]
Abstract
New ligands for in vivo brain imaging of serotonin transporter (SERT) with single photon emission tomography (SPECT) were prepared and evaluated. An efficient synthesis and radiolabeling of a biphenylthiol, FLIP-IDAM, 4, was accomplished. The affinity of FLIP-IDAM was evaluated by an in vitro inhibitory binding assay using [(125)I]-IDAM as radioligand in rat brain tissue homogenates (K(i) = 0.03 nM). New [(125)I]Flip-IDAM exhibited excellent binding affinity to SERT binding sites with a high hypothalamus to cerebellum ratio of 4 at 30 min post iv injection. The faster in vivo kinetics for brain uptake and a rapid washout from non-specific regions provide excellent signal to noise ratio. This new agent, when labeled with (123)I, may be a useful imaging agent for mapping SERT binding sites in the human brain.
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Affiliation(s)
- Pinguan Zheng
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
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