1
|
Kolks N, Neumaier F, Neumaier B, Zlatopolskiy BD. Preparation of NIn-Methyl-6-[ 18F]fluoro- and 5-Hydroxy-7-[ 18F]fluorotryptophans as Candidate PET-Tracers for Pathway-Specific Visualization of Tryptophan Metabolism. Int J Mol Sci 2023; 24:15251. [PMID: 37894930 PMCID: PMC10607147 DOI: 10.3390/ijms242015251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/09/2023] [Accepted: 10/14/2023] [Indexed: 10/29/2023] Open
Abstract
Tryptophan (Trp) is an essential proteinogenic amino acid and metabolic precursor for several signaling molecules that has been implicated in many physiological and pathological processes. Since the two main branches of Trp metabolism-serotonin biosynthesis and kynurenine pathway-are differently affected by a variety of neurological and neoplastic diseases, selective visualization of these pathways is of high clinical relevance. However, while positron emission tomography (PET) with existing probes can be used for non-invasive assessment of total Trp metabolism, optimal imaging agents for pathway-specific PET imaging are still lacking. In this work, we describe the preparation of two 18F-labeled Trp derivatives, NIn-methyl-6-[18F]fluorotryptophan (NIn-Me-6-[18F]FTrp) and 5-hydroxy-7-[18F]fluorotryptophan (5-HO-7-[18F]FTrp). We also report feasible synthetic routes for the preparation of the hitherto unknown boronate radiolabeling precursors and non-radioactive reference compounds. Under optimized conditions, alcohol-enhanced Cu-mediated radiofluorination of the respective precursors afforded NIn-Me-6-[18F]FTrp and 5-HO-7-[18F]FTrp as application-ready solutions in radiochemical yields of 45 ± 7% and 29 ± 4%, respectively. As such, our work provides access to two promising candidate probes for pathway-specific visualization of Trp metabolism in amounts sufficient for their preclinical evaluation.
Collapse
Affiliation(s)
- Niklas Kolks
- Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany; (N.K.); (F.N.); (B.D.Z.)
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Felix Neumaier
- Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany; (N.K.); (F.N.); (B.D.Z.)
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Bernd Neumaier
- Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany; (N.K.); (F.N.); (B.D.Z.)
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Boris D. Zlatopolskiy
- Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52428 Jülich, Germany; (N.K.); (F.N.); (B.D.Z.)
- Institute of Radiochemistry and Experimental Molecular Imaging, Faculty of Medicine and University Hospital Cologne, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| |
Collapse
|
2
|
Hanaoka H, Ohshima Y, Suzuki H, Sasaki I, Watabe T, Ooe K, Watanabe S, Ishioka NS. Enhancing the Therapeutic Effect of 2- 211At-astato-α-methyl-L-phenylalanine with Probenecid Loading. Cancers (Basel) 2021; 13:cancers13215514. [PMID: 34771676 PMCID: PMC8583516 DOI: 10.3390/cancers13215514] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022] Open
Abstract
Simple Summary To enhance the therapeutic effect of 2-211At-astato-α-methyl-L-phenylalanine (2-211At-AAMP), a radiopharmaceutical for targeted alpha therapy, we evaluated the effect of probenecid loading on its biodistribution and therapeutic effect in mice. Probenecid preloading significantly delayed the clearance of 2-211At-AAMP from the blood, increasing its accumulation in tumors. Consequently, the therapeutic effect of 2-211At-AAMP markedly improved. These results indicate that 2-211At-AAMP with probenecid loading is useful for the treatment of various types of cancers. Abstract L-type amino acid transporter 1 (LAT1) might be a useful target for tumor therapy since it is highly expressed in various types of cancers. We previously developed an astatine-211 (211At)-labeled amino acid derivative, 2-211At-astato-α-methyl-L-phenylalanine (2-211At-AAMP), and demonstrated its therapeutic potential for LAT1-positive cancers. However, the therapeutic effect of 2-211At-AAMP was insufficient, probably due to its low tumor retention. The preloading of probenecid, an organic anion transporter inhibitor, can delay the clearance of some amino acid tracers from the blood and consequently increase their accumulation in tumors. In this study, we evaluated the effect of probenecid preloading on the biodistribution and therapeutic effect of 2-211At-AAMP in mice. In biodistribution studies, the blood radioactivity of 2-211At-AAMP significantly increased with probenecid preloading. Consequently, the accumulation of 2-211At-AAMP in tumors was significantly higher with probenecid than without probenecid loading. In a therapeutic study, tumor growth was suppressed by 2-211At-AAMP with probenecid, and the tumor volume was significantly lower in the treatment group than in the untreated control group from day 2 to day 30 (end of the follow-up period) after treatment. These results indicate that probenecid loading could improve the therapeutic effect of 2-211At-AAMP by increasing its accumulation in tumors.
Collapse
Affiliation(s)
- Hirofumi Hanaoka
- Faculty of Medicine, Kansai Medical University, 2-5-1 Shin-machi, Hirakata 573-1010, Osaka, Japan
- Department of Radiotheranostics, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi 371-8511, Gunma, Japan
- Correspondence: ; Tel.: +81-72-804-2452
| | - Yasuhiro Ohshima
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Hiroyuki Suzuki
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Chiba, Japan;
| | - Ichiro Sasaki
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Tadashi Watabe
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, 1-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (T.W.); (K.O.)
| | - Kazuhiro Ooe
- Department of Nuclear Medicine and Tracer Kinetics, Graduate School of Medicine, Osaka University, 1-1 Yamadaoka, Suita 565-0871, Osaka, Japan; (T.W.); (K.O.)
| | - Shigeki Watanabe
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| | - Noriko S. Ishioka
- Department of Radiation-Applied Biology Research, Quantum Beam Science Research Directorate, National Institute for Quantum Science and Technology, 1233 Watanuki-machi, Takasaki 370-1292, Gunma, Japan; (Y.O.); (I.S.); (S.W.); (N.S.I.)
| |
Collapse
|
3
|
Fluorine-18-Labeled PET Radiotracers for Imaging Tryptophan Uptake and Metabolism: a Systematic Review. Mol Imaging Biol 2021; 22:805-819. [PMID: 31512038 DOI: 10.1007/s11307-019-01430-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Due to its metabolism via the serotonin and kynurenine pathways, tryptophan plays a key role in multiple disease processes including cancer. Imaging tryptophan uptake and metabolism in vivo can be achieved with tryptophan derivative positron emission tomography (PET) radiotracers. While human studies with such tracers have been confined to C-11-labeled compounds, preclinical development of F-18-labeled tryptophan-based radiotracers has surged in recent years. We performed a systematic review of studies reporting on such F-18-labeled tryptophan tracers to summarize and compare their biological characteristics and their potential for tumor imaging, with a particular focus on key enzymes of the kynurenine pathway (indoleamine 2,3-dioxygenase [IDO] and tryptophan 2,3-dioxygenase [TDO]), which play an important role in tumoral immune resistance. From a PubMed search, English language articles including data on the preparation and radiochemical and/or biological characteristics of F-18-labeled tryptophan derivative radiotracers were reviewed. A total of 19 original papers included data on 15 unique radiotracers, the majority of which were synthesized with an adequate radiochemical yield. Automated synthesis was reported for 1-(2-[18F]fluoroethyl)-L-tryptophan, the most extensively evaluated tracer thus far. Biodistribution studies showed high uptake in the pancreas, while the L-type amino acid transporter was the dominant transport mechanism for most of the reviewed tracers. Tracers tested for tumor uptake showed accumulation in tumor cell lines in vitro and in xenografts in vivo, often with favorable tumor-to-background uptake ratios in comparison with clinically used F-18-labeled radiotracers. Five tracers showed promise for imaging IDO activity, including 1-(2-[18F]fluoroethyl)-L-tryptophan and a F-18-labeled analog of alpha-[11C]methyl-L-tryptophan tested clinically in previous studies. Two radiotracers were metabolized by TDO but showed defluorination in vivo. In summary, most F-18-labeled tryptophan derivative PET tracers share common transport mechanisms and biodistribution characteristics. Several reported tracers could be candidates for further testing and validation toward PET imaging applications in a variety of human diseases.
Collapse
|
4
|
Demine S, Schulte ML, Territo PR, Eizirik DL. Beta Cell Imaging-From Pre-Clinical Validation to First in Man Testing. Int J Mol Sci 2020; 21:E7274. [PMID: 33019671 PMCID: PMC7582644 DOI: 10.3390/ijms21197274] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/21/2020] [Accepted: 09/28/2020] [Indexed: 12/14/2022] Open
Abstract
There are presently no reliable ways to quantify human pancreatic beta cell mass (BCM) in vivo, which prevents an accurate understanding of the progressive beta cell loss in diabetes or following islet transplantation. Furthermore, the lack of beta cell imaging hampers the evaluation of the impact of new drugs aiming to prevent beta cell loss or to restore BCM in diabetes. We presently discuss the potential value of BCM determination as a cornerstone for individualized therapies in diabetes, describe the presently available probes for human BCM evaluation, and discuss our approach for the discovery of novel beta cell biomarkers, based on the determination of specific splice variants present in human beta cells. This has already led to the identification of DPP6 and FXYD2ga as two promising targets for human BCM imaging, and is followed by a discussion of potential safety issues, the role for radiochemistry in the improvement of BCM imaging, and concludes with an overview of the different steps from pre-clinical validation to a first-in-man trial for novel tracers.
Collapse
Affiliation(s)
- Stephane Demine
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA;
| | - Michael L. Schulte
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (M.L.S.); (P.R.T.)
| | - Paul R. Territo
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (M.L.S.); (P.R.T.)
- Division of Clinical Pharmacology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Decio L. Eizirik
- Indiana Biosciences Research Institute, Indianapolis, IN 46202, USA;
- ULB Center for Diabetes Research, Medical Faculty, Université Libre de Bruxelles (ULB), 1070 Brussels, Belgium
| |
Collapse
|
5
|
Zlatopolskiy BD, Endepols H, Krasikova RN, Fedorova OS, Ermert J, Neumaier B. 11C- and 18F-labelled tryptophans as PET-tracers for imaging of altered tryptophan metabolism in age-associated disorders. RUSSIAN CHEMICAL REVIEWS 2020. [DOI: 10.1070/rcr4954] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The ageing of the world’s population is the result of increased life expectancy observed in almost all countries throughout the world. Consequently, a rising tide of ageing-associated disorders, like cancer and neurodegenerative diseases, represents one of the main global challenges of the 21st century. The ability of mankind to overcome these challenges is directly dependent on the capability to develop novel methods for therapy and diagnosis of age-associated diseases. One hallmark of age-related pathologies is an altered tryptophan metabolism. Numerous pathological processes including neurodegenerative and neurological diseases like epilepsy, Parkinson’s and Alzheimer’s diseases, cancer and diabetes exhibit marked changes in tryptophan metabolism. Visualization of key processes of tryptophan metabolic pathways, especially using positron emission tomography (PET) and related hybrid methods like PET/CT and PET/MRI, can be exploited to early detect the aforementioned disorders with considerable accuracy, allowing appropriate and timely treatment of patients. Here we review the published 11C- and 18F-labelled tryptophans with respect to the production and also preclinical and clinical evaluation as PET-tracers for visualization of different branches of tryptophan metabolism.
The bibliography includes 159 references.
Collapse
|
6
|
Mahendra I, Hanaoka H, Yamaguchi A, Amartuvshin T, Tsushima Y. Diagnosis of bladder cancer using 18F-labeled α-methyl-phenylalanine tracers in a mouse model. Ann Nucl Med 2020; 34:329-336. [PMID: 32144655 DOI: 10.1007/s12149-020-01452-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 02/21/2020] [Indexed: 12/24/2022]
Abstract
OBJECTIVE Although 2-18F-fluoro-2-deoxy-glucose (18F-FDG) has established roles in the diagnosis of a variety of cancers, it has limited value in the detection of primary/recurrent lesions in the bladder, mainly because of interference by the pooled radioactivity in the urine. Our previous study revealed promising properties of L- and D-2-18F-α-methyl-phenylalanine (2-18F-FAMP) as radiotracers; i.e., their rapid blood clearance and low renal accumulation. In the present study we evaluated the utility of L- and D-2-18F-FAMP for imaging bladder cancer in a mouse model. METHODS We used the human bladder cancer cell line HT1376 to prepare a bladder cancer xenograft model in mice bearing both orthotopic and subcutaneous tumors. Biodistribution and PET imaging studies were performed at 1 and 3 h after injection of L-2-18F-FAMP or D-2-18F-FAMP. 18F-FDG was used as a control. RESULTS At 1 h after injection, greater accumulations of both L-2-18F-FAMP and D-2-18F-FAMP were observed in the orthotopic tumors compared to 18F-FDG. The orthotopic tumor-to-muscle ratio of D-2-18F-FAMP was significantly higher than that of 18F-FDG (p < 0.01), because of the rapid blood clearance of D-2-18F-FAMP. L-2-18F-FAMP showed the highest subcutaneous tumor-to-muscle ratio (p < 0.01) due to its high subcutaneous tumor uptake. Compared to L-2-18F-FAMP, D-2-18F-FAMP exhibited faster clearance and lower kidney accumulation. In the PET imaging studies, L- and D-2-18F-FAMP both clearly visualized the orthotopic bladder tumors at 1 h after injection. CONCLUSION Our study showed that L-2-18F-FAMP and D-2-18F-FAMP have the potential to detect bladder cancer.
Collapse
Affiliation(s)
- Isa Mahendra
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan.,Center for Applied Nuclear Science and Technology, National Nuclear Energy Agency of Indonesia, Tamansari 71, Bandung, West Java, 40132, Indonesia
| | - Hirofumi Hanaoka
- Department of Bioimaging and Information Analysis, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan.
| | - Aiko Yamaguchi
- Department of Bioimaging and Information Analysis, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan.,Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX, 77054, USA
| | - Tumenjargal Amartuvshin
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan
| | - Yoshito Tsushima
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan.,Research Program for Diagnostic and Molecular Imaging, Division of Integrated Oncology Research, Gunma University Initiative for Advanced Research (GIAR), Gunma University Graduate School of Medicine, 3-39-22 Showa, Maebashi, 371-8511, Japan
| |
Collapse
|
7
|
Hanaoka H, Ohshima Y, Yamaguchi A, Suzuki H, Ishioka NS, Higuchi T, Arano Y, Tsushima Y. Novel 18F-Labeled α-Methyl-Phenylalanine Derivative with High Tumor Accumulation and Ideal Pharmacokinetics for Tumor-Specific Imaging. Mol Pharm 2019; 16:3609-3616. [DOI: 10.1021/acs.molpharmaceut.9b00446] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Hirofumi Hanaoka
- Department of Bioimaging Information Analysis, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| | - Yasuhiro Ohshima
- Project “Medical Radioisotope Application”, Department of Radiation-Applied Biology Research, Takasaki Advanced Radiation Research Institute, Quantum Beam Advanced Research Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Takasaki 370-1292, Japan
| | - Aiko Yamaguchi
- Department of Bioimaging Information Analysis, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| | - Hiroyuki Suzuki
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Noriko S. Ishioka
- Project “Medical Radioisotope Application”, Department of Radiation-Applied Biology Research, Takasaki Advanced Radiation Research Institute, Quantum Beam Advanced Research Directorate, National Institutes for Quantum and Radiological Science and Technology (QST), Takasaki 370-1292, Japan
| | - Tetsuya Higuchi
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| | - Yasushi Arano
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Yoshito Tsushima
- Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Graduate School of Medicine, Maebashi 371-8511, Japan
| |
Collapse
|
8
|
Abbas A, Yu L, Lalonde T, Wu D, Thiessen JD, Luyt LG, Dhanvantari S. Development and Characterization of an 18F-labeled Ghrelin Peptidomimetic for Imaging the Cardiac Growth Hormone Secretagogue Receptor. Mol Imaging 2018; 17:1536012118809587. [PMID: 30394854 PMCID: PMC6236854 DOI: 10.1177/1536012118809587] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
One-third of patients with heart disease develop heart failure, which is diagnosed
through imaging and detection of circulating biomarkers. Imaging strategies reveal
morphologic and functional changes but fall short of detecting molecular abnormalities
that can lead to heart failure, and circulating biomarkers are not cardiac specific. Thus,
there is critical need for biomarkers that are endogenous to myocardial tissues. The
cardiac growth hormone secretagogue receptor 1a (GHSR1a), which binds the hormone ghrelin,
is a potential biomarker for heart failure. We have synthesized and characterized a novel
ghrelin peptidomimetic tracer, an 18F-labeled analogue of G-7039, for positron
emission tomography (PET) imaging of cardiac GHSR1a. In vitro analysis showed enhanced
serum stability compared to natural ghrelin and significantly increased cellular uptake in
GHSR1a-expressing OVCAR cells. Biodistribution studies in mice showed that tissue uptake
of the tracer was independent of circulating ghrelin levels, and there was negligible
cardiac uptake and high uptake in the liver, intestines, and kidneys. Specificity of
tracer uptake was assessed using ghsr −/− mice; both static and dynamic PET imaging revealed no difference in cardiac
uptake, and there was no significant correlation between cardiac standardized uptake
values and GHSR1a expression. Our study lays the groundwork for further refinement of
peptidomimetic PET tracers targeting cardiac GHSR1a.
Collapse
Affiliation(s)
- Ahmed Abbas
- 1 Department of Medical Biophysics, Western University, London, Ontario, Canada
| | - Lihai Yu
- 2 Department of Chemistry, Western University, London, Ontario, Canada
| | - Tyler Lalonde
- 2 Department of Chemistry, Western University, London, Ontario, Canada
| | - Derek Wu
- 3 Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada
| | - Jonathan D Thiessen
- 1 Department of Medical Biophysics, Western University, London, Ontario, Canada.,4 Imaging Research, Lawson Health Research Institute, London, Ontario, Canada
| | - Leonard G Luyt
- 2 Department of Chemistry, Western University, London, Ontario, Canada.,4 Imaging Research, Lawson Health Research Institute, London, Ontario, Canada.,5 Department of oncology, Western University, London, Ontario, Canada
| | - Savita Dhanvantari
- 1 Department of Medical Biophysics, Western University, London, Ontario, Canada.,3 Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada.,4 Imaging Research, Lawson Health Research Institute, London, Ontario, Canada.,6 Metabolism/Diabetes, Lawson Health Research Institute, London, Ontario, Canada
| |
Collapse
|