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Li J, Ni B, Yu X, Wang C, Li L, Zhou Y, Gu Y, Huang G, Hou J, Liu J, Chen Y. Metabolic kinetic modeling of [ 11C]methionine based on total-body PET in multiple myeloma. Eur J Nucl Med Mol Imaging 2023; 50:2683-2691. [PMID: 37039900 DOI: 10.1007/s00259-023-06219-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 04/02/2023] [Indexed: 04/12/2023]
Abstract
PURPOSE Multiple myeloma (MM) is a malignant disease characterized by the secretion of monoclonal immunoglobulins and has a high demand for amino acids. [11C]methionine total-body PET is capable of noninvasive dynamic monitoring of radiotracer in vivo, thus providing a way to reveal the dynamic changes of myeloma metabolism. This study aims to analyze the metabolic process of [11C]methionine based on kinetic modeling, and to preliminary reveal its application value in MM. METHODS Dynamic total-body [11C]methionine PET/CT was conducted with uEXPLORER in 12 subjects (9 MM patients and 3 controls). The tissue time activity curves (TACs) of organs and bone marrows were extracted. Model fitting of TACs was operated using PMOD Kinetic Modeling. After validation by Goodness of fit (GOF), the reversible two-tissue compartment model (2T4k) was used to further analysis. R software was used to analyze the correlation between kinetic parameters and clinical indicators. RESULTS The 2T4k has passed the criterion of GOF and was used to fit the data of 0-20 minutes. The [11C]methionine net uptake rate (Ki) was significantly higher in the MM lesions than in the non-myeloma controls (control: 0.040±0.007 mL/g/min, MM: 0.171±0.108 mL/g/min, p=0.009). The Ki values were found to be correlated with M protein levels in MM patients. MM patients with t(4;14) translocations had an elevated k4 value compared with t(4;14) negative patients. CONCLUSION MM lesions have a propensity for uptake of [11C]methionine. The serum levels of M protein are correlated with [11C]methionine uptake rate in myeloma. Metabolic classification based on the k4 value may be a promising strategy for risk stratification in MM.
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Affiliation(s)
- Jiajin Li
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Beiwen Ni
- Department of Hematology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Xiaofeng Yu
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Cheng Wang
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Lianghua Li
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
| | - Yun Zhou
- Central Research Institute, United Imaging Healthcare Group Co., Ltd, Shanghai, 200032, China
| | - Yue Gu
- Central Research Institute, United Imaging Healthcare Group Co., Ltd, Shanghai, 200032, China
| | - Gang Huang
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China
- Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai, 201318, China
| | - Jian Hou
- Department of Hematology, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.
| | - Jianjun Liu
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.
| | - Yumei Chen
- Department of Nuclear Medicine, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, China.
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Regional Characterization of the Gottingen Minipig Brain by [18 F]FDG Dynamic Pet Modeling. J Med Biol Eng 2022. [DOI: 10.1007/s40846-022-00739-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Abstract
Purpose
To determine the best kinetic model to be applied on dynamic brain [18 F]FDG PET images by characterizing the regional brain glucose metabolism of normal Göttingen minipigs.
Methods
Nine Göttingen minipigs were scanned with a clinical PET/CT tomograph, starting from the injection of an intravenous bolus of [18 F]FDG, for about 25 min. Dynamic images were reconstructed and nine brain regions of interest (ROI), plus a vascular region, were defined and time-activity curves (TAC) were determined.
Three kinetic models were considered for fitting with experimental TACs: one-tissue compartment model 1TC, two-tissue irreversible compartment model 2TCi and two-tissue reversible model 2TC. Akaike Information Criterion was considered to evaluate the goodness of each model fitting. Regional and global kinetic parameter values were evaluated, in addition to the partition coefficient, net influx rate and retention index (RI).
Results
Both 2TCi and 2TC models turned out to be good choices for the next analysis. Parameter values were very similar between the different brain regions, with similar values to when the brain as a whole is considered (kinetic parameters mean values, from 2TCi model: K1 = 1.0 ml/g/min, k2 = 0.49 min− 1, k3 = 0.034 min− 1, K1/k2 = 2.14ml/g, Ki =0.069 ml/g/min; from 2TC model: K1 = 1.10 ml/g/min, k2 = 0.54 min− 1, k3 = 0.058 min− 1, k4 = 0.039 min− 1, K1/k2 = 2.18 ml/g, Ki = 0.10 ml/g/min; RI mean ± sd: 0.147 ± 0.037 min− 1), with the exception of the cerebellum (mean values from the 2TCi model: K1 = 0.52 ml/g/min, k2 = 0.56 min− 1, k3 = 0.025 min− 1, K1/k2 = 0.98ml/g, Ki=0.022 ml/g/min; from 2TC model: K1 = 0.54 ml/g/min, k2 = 0.61 min− 1, k3 = 0.044 min− 1, k4 = 0.038 min− 1, K1/k2 = 0.95ml/g, Ki=0.032 ml/g/min; RI mean ± sd: 0.071 ± 0.018 min− 1).
Conclusion
The two-tissue model is able to describe the regional brain metabolism in Göttingen minipigs. Compared to the 2TCi model, in the 2TC model the k4 micro-parameter was also evaluated. This led to adjustments of the other microparameters, especially k3 and consequently the net influx rate Ki. For healthy minipigs, the glucose metabolism was similar in all of the brain regions analyzed, with the exception of the cerebellum, where the FDG uptake was lower.
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Afzelius P, Morsing MK, Nielsen OL, Alstrup AKO, Jensen SB, Jødal L. Lymph Nodes Draining Infections Investigated by PET and Immunohistochemistry in a Juvenile Porcine Model. Molecules 2022; 27:molecules27092792. [PMID: 35566137 PMCID: PMC9104488 DOI: 10.3390/molecules27092792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/23/2022] [Accepted: 04/25/2022] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND [18F]FDG and [11C]methionine accumulate in lymph nodes draining S. aureus -infected foci. The lymph nodes were characterized by weight, [11C]methionine- and [18F]FDG-positron emissions tomography (PET)/computed tomography (CT), and immunohistochemical (IHC)-staining. METHODS 20 pigs inoculated with S. aureus into the right femoral artery were PET/CT-scanned with [18F]FDG, and nine of the pigs were additionally scanned with [11C]methionine. Mammary, medial iliac, and popliteal lymph nodes from the left and right hind limbs were weighed. IHC-staining for calculations of area fractions of Ki-67, L1, and IL-8 positive cells was done in mammary and popliteal lymph nodes from the nine pigs. RESULTS The pigs developed one to six osteomyelitis foci. Some pigs developed contiguous infections of peri-osseous tissue and inoculation-site abscesses. Weights of mammary and medial iliac lymph nodes and their [18F]FDG maximum Standardized Uptake Values (SUVFDGmax) showed a significant increase in the inoculated limb compared to the left limb. Popliteal lymph node weight and their FDG uptake did not differ significantly between hind limbs. Area fractions of Ki-67 and IL-8 in the right mammary lymph nodes and SUVMetmax in the right popliteal lymph nodes were significantly increased compared with the left side. CONCLUSION The PET-tracers [18F]FDG and [11C]methionine, and the IHC- markers Ki-67 and IL-8, but not L1, showed increased values in lymph nodes draining soft tissues infected with S. aureus. The increase in [11C]methionine may indicate a more acute lymph node response, whereas an increase in [18F]FDG may indicate a more chronic response.
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Affiliation(s)
- Pia Afzelius
- Department of Clinical Physiology and Nuclear Medicine Zealand Koege, University Hospital of Copenhagen, 4600 Copenhagen, Denmark
- Department of Nuclear Medicine, Aalborg University Hospital, 9000 Aalborg, Denmark; (S.B.J.); (L.J.)
- Correspondence:
| | - Malene Kjelin Morsing
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg C, Denmark; (M.K.M.); (O.L.N.)
| | - Ole Lerberg Nielsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, 1870 Frederiksberg C, Denmark; (M.K.M.); (O.L.N.)
| | - Aage Kristian Olsen Alstrup
- Department of Nuclear Medicine and PET, Aarhus University Hospital, Skejby, 8200 Aarhus, Denmark;
- Department of Clinical Medicine, Aarhus University, Skejby, 8200 Aarhus, Denmark
| | - Svend Borup Jensen
- Department of Nuclear Medicine, Aalborg University Hospital, 9000 Aalborg, Denmark; (S.B.J.); (L.J.)
- Department of Chemistry and Biosciences, Aalborg University, 9220 Aalborg, Denmark
| | - Lars Jødal
- Department of Nuclear Medicine, Aalborg University Hospital, 9000 Aalborg, Denmark; (S.B.J.); (L.J.)
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Rubitschung K, Sherwood A, Crisologo AP, Bhavan K, Haley RW, Wukich DK, Castellino L, Hwang H, La Fontaine J, Chhabra A, Lavery L, Öz OK. Pathophysiology and Molecular Imaging of Diabetic Foot Infections. Int J Mol Sci 2021; 22:11552. [PMID: 34768982 PMCID: PMC8584017 DOI: 10.3390/ijms222111552] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 12/27/2022] Open
Abstract
Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.
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Affiliation(s)
- Katie Rubitschung
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Andrew P. Crisologo
- Department of Plastic Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0558, USA;
| | - Kavita Bhavan
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.B.); (L.C.)
| | - Robert W. Haley
- Department of Internal Medicine, Epidemiology Division, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Dane K. Wukich
- Department of Orthopedic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Laila Castellino
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.B.); (L.C.)
| | - Helena Hwang
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA;
| | - Javier La Fontaine
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.L.F.); (L.L.)
| | - Avneesh Chhabra
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
| | - Lawrence Lavery
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (J.L.F.); (L.L.)
| | - Orhan K. Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA; (K.R.); (A.S.); (A.C.)
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Rubitschung K, Sherwood A, Crisologo AP, Bhavan K, Haley RW, Wukich DK, Castellino L, Hwang H, La Fontaine J, Chhabra A, Lavery L, Öz OK. Pathophysiology and Molecular Imaging of Diabetic Foot Infections. Int J Mol Sci 2021; 22:ijms222111552. [PMID: 34768982 DOI: 10.3390/ijms222111552.pmid:34768982;pmcid:pmc8584017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 05/27/2023] Open
Abstract
Diabetic foot infection is the leading cause of non-traumatic lower limb amputations worldwide. In addition, diabetes mellitus and sequela of the disease are increasing in prevalence. In 2017, 9.4% of Americans were diagnosed with diabetes mellitus (DM). The growing pervasiveness and financial implications of diabetic foot infection (DFI) indicate an acute need for improved clinical assessment and treatment. Complex pathophysiology and suboptimal specificity of current non-invasive imaging modalities have made diagnosis and treatment response challenging. Current anatomical and molecular clinical imaging strategies have mainly targeted the host's immune responses rather than the unique metabolism of the invading microorganism. Advances in imaging have the potential to reduce the impact of these problems and improve the assessment of DFI, particularly in distinguishing infection of soft tissue alone from osteomyelitis (OM). This review presents a summary of the known pathophysiology of DFI, the molecular basis of current and emerging diagnostic imaging techniques, and the mechanistic links of these imaging techniques to the pathophysiology of diabetic foot infections.
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Affiliation(s)
- Katie Rubitschung
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Amber Sherwood
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Andrew P Crisologo
- Department of Plastic Surgery, University of Cincinnati, 231 Albert Sabin Way, Cincinnati, OH 45267-0558, USA
| | - Kavita Bhavan
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Robert W Haley
- Department of Internal Medicine, Epidemiology Division, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Dane K Wukich
- Department of Orthopedic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Laila Castellino
- Department of Internal Medicine, Division of Infectious Diseases and Geographic Medicine, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Helena Hwang
- Department of Pathology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Javier La Fontaine
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Avneesh Chhabra
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Lawrence Lavery
- Department of Plastic Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
| | - Orhan K Öz
- Department of Radiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-8542, USA
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Jødal L, Afzelius P, Alstrup AKO, Jensen SB. Radiotracers for Bone Marrow Infection Imaging. Molecules 2021; 26:3159. [PMID: 34070537 PMCID: PMC8198735 DOI: 10.3390/molecules26113159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/19/2021] [Accepted: 05/21/2021] [Indexed: 12/11/2022] Open
Abstract
INTRODUCTION Radiotracers are widely used in medical imaging, using techniques of gamma-camera imaging (scintigraphy and SPECT) or positron emission tomography (PET). In bone marrow infection, there is no single routine test available that can detect infection with sufficiently high diagnostic accuracy. Here, we review radiotracers used for imaging of bone marrow infection, also known as osteomyelitis, with a focus on why these molecules are relevant for the task, based on their physiological uptake mechanisms. The review comprises [67Ga]Ga-citrate, radiolabelled leukocytes, radiolabelled nanocolloids (bone marrow) and radiolabelled phosphonates (bone structure), and [18F]FDG as established radiotracers for bone marrow infection imaging. Tracers that are under development or testing for this purpose include [68Ga]Ga-citrate, [18F]FDG, [18F]FDS and other non-glucose sugar analogues, [15O]water, [11C]methionine, [11C]donepezil, [99mTc]Tc-IL-8, [68Ga]Ga-Siglec-9, phage-display selected peptides, and the antimicrobial peptide [99mTc]Tc-UBI29-41 or [68Ga]Ga-NOTA-UBI29-41. CONCLUSION Molecular radiotracers allow studies of physiological processes such as infection. None of the reviewed molecules are ideal for the imaging of infections, whether bone marrow or otherwise, but each can give information about a separate aspect such as physiology or biochemistry. Knowledge of uptake mechanisms, pitfalls, and challenges is useful in both the use and development of medically relevant radioactive tracers.
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Affiliation(s)
- Lars Jødal
- Department of Nuclear Medicine, Aalborg University Hospital, DK-9000 Aalborg, Denmark;
| | - Pia Afzelius
- Zealand Hospital, Køge, Copenhagen University Hospital, DK-4600 Køge, Denmark;
| | - Aage Kristian Olsen Alstrup
- Department of Nuclear Medicine & PET, Aarhus University Hospital, DK-8200 Aarhus, Denmark;
- Department of Clinical Medicine, Aarhus University, DK-8000 Aarhus, Denmark
| | - Svend Borup Jensen
- Department of Nuclear Medicine, Aalborg University Hospital, DK-9000 Aalborg, Denmark;
- Department of Chemistry and Biosciences, Aalborg University, DK-9220 Aalborg, Denmark
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Xu T, Chen Y. Research Progress of [ 68Ga]Citrate PET's Utility in Infection and Inflammation Imaging: a Review. Mol Imaging Biol 2021; 22:22-32. [PMID: 31076971 DOI: 10.1007/s11307-019-01366-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Imaging diagnosis of infection and inflammation has been challenging for many years. Infection imaging agents commonly used in nuclear medicine, such as [67Ga]citrate, 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG), and radionuclide-labeled leukocytes, have their own shortcomings. Identification of a tracer with considerable economic benefit, high specificity, and low radiation dose has become clinically urgent. In the twenty-first century, with the increasing availability of positron emission tomography (PET) devices and the commercialization of Ge-68/Ga-68 generators, the study of [68Ga]citrate applications for infection and inflammation has increased and shown good potential. In this report, the research progress that supports [68Ga]citrate PET's applications various infectious diseases and inflammation is reviewed.
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Affiliation(s)
- Tingting Xu
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, No. 25, Taiping St., Luzhou, 646000, Sichuan, People's Republic of China
| | - Yue Chen
- Department of Nuclear Medicine, The Affiliated Hospital of Southwest Medical University, No. 25, Taiping St., Luzhou, 646000, Sichuan, People's Republic of China. .,Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Luzhou, Sichuan, People's Republic of China.
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Alstrup AK, Afzelius PM, Jensen SB, Leifsson PS, Wegener KM, Nielsen OL. Effects of Long-term Anesthesia, Blood Sampling, Transportation, and Infection Status on Hearts and Brains in Pigs Inoculated with Staphylococcus aureus and Used for Imaging Studies. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE 2019; 59:74-84. [PMID: 31847929 DOI: 10.30802/aalas-jaalas-19-000062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Laboratory animals are widely used in imaging studies, including infection, heart, and brain research. Compared with rodents, pigs are especially useful because of their large organ sizes, ability to tolerate long-term anesthesia, and substantial blood volume, which allows repeated blood sampling. These factors are particularly important in positron emission tomography studies of potential new radioactive tracers, because the scans often are prolonged; in addition, kinetic studies involving repeated blood sampling may be performed to establish the optimal scan time. However, protracted studies may affect the cardiovascular system, brain, and other organs. This raises the question of how to monitor and counteract the effects of longterm anesthesia in pigs in a typical experimental setting yet prevent introducing bias into the experiment. To address this question, we investigated the effects of long-term anesthesia (maximum, 18 h), repeated blood sampling (maximum of 20 mL blood per kilogram body weight), and road transportation (as long as 1.5 h between 2 imaging centers) on key variables of lung, heart, and brain function in the context of a well-established pig model of Staphylococcus aureus infection. Pulse rate, oxygen saturation, body temperature, arterial pressure of CO₂, and urine production were stable during anesthesia for at least 16 h, whereas blood glucose slowly decreased. Hct and leukocyte count decreased due to repeated blood sampling. During road transportation, blood lactate levels increased 5 fold and arterial pressure of O₂ decreased by 50%. Repeated CT scans, necropsy results, and histopathology findings documented progressive lung changes and acute cardiac necrosis. No lesions indicative of hypoxia were found in brain. The study data show that the typical monitoring parameters do not fully depict the cardiovascular state of pigs during prolonged anesthesia. We recommend streamlining experimental protocols for imaging studies in pigs to avoid organ pathology.
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Jødal L, Roivainen A, Oikonen V, Jalkanen S, Hansen SB, Afzelius P, Alstrup AKO, Nielsen OL, Jensen SB. Kinetic Modelling of [ 68Ga]Ga-DOTA-Siglec-9 in Porcine Osteomyelitis and Soft Tissue Infections. Molecules 2019; 24:molecules24224094. [PMID: 31766140 PMCID: PMC6891593 DOI: 10.3390/molecules24224094] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/07/2019] [Accepted: 11/10/2019] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND [68Ga]Ga-DOTA-Siglec-9 is a positron emission tomography (PET) radioligand for vascular adhesion protein 1 (VAP-1), a protein involved in leukocyte trafficking. The tracer facilitates the imaging of inflammation and infection. Here, we studied the pharmacokinetic modelling of [68Ga]Ga-DOTA-Siglec-9 in osteomyelitis and soft tissue infections in pigs. METHODS Eight pigs with osteomyelitis and soft tissue infections in the right hind limb were dynamically PET scanned for 60 min along with arterial blood sampling. The fraction of radioactivity in the blood accounted for by the parent tracer was evaluated with radio-high-performance liquid chromatography. One- and two-tissue compartment models were used for pharmacokinetic evaluation. Post-mortem soft tissue samples from one pig were analysed with anti-VAP-1 immunofluorescence. In each analysis, the animal's non-infected left hind limb was used as a control. RESULTS Tracer uptake was elevated in soft tissue infections but remained low in osteomyelitis. The kinetics of [68Ga]Ga-DOTA-Siglec-9 followed a reversible 2-tissue compartment model. The tracer metabolized quickly; however, taking this into account, produced more ambiguous results. Infected soft tissue samples showed endothelial cell surface expression of the Siglec-9 receptor VAP-1. CONCLUSION The kinetics of [68Ga]Ga-DOTA-Siglec-9 uptake in porcine soft tissue infections are best described by the 2-tissue compartment model.
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Affiliation(s)
- Lars Jødal
- Department of Nuclear Medicine, Aalborg University Hospital, DK-9000 Aalborg, Denmark;
- Correspondence: ; Tel.: +45-9766-5500
| | - Anne Roivainen
- Turku PET Centre, Turku University Hospital, FI-20520 Turku, Finland; (A.R.); (V.O.)
- Turku PET Centre, University of Turku, FI-20520 Turku, Finland
| | - Vesa Oikonen
- Turku PET Centre, Turku University Hospital, FI-20520 Turku, Finland; (A.R.); (V.O.)
- Turku PET Centre, University of Turku, FI-20520 Turku, Finland
| | - Sirpa Jalkanen
- MediCity Research Laboratory and Institute of Biomedicine, University of Turku, FI-20520 Turku, Finland;
| | - Søren B. Hansen
- Department of Nuclear Medicine and PET, Aarhus University Hospital, DK-8200 Aarhus, Denmark; (S.B.H.); (A.K.O.A.)
| | - Pia Afzelius
- North Zealand Hospital, Hillerød, Copenhagen University Hospital, DK-3400 Hillerød, Denmark;
| | - Aage K. O. Alstrup
- Department of Nuclear Medicine and PET, Aarhus University Hospital, DK-8200 Aarhus, Denmark; (S.B.H.); (A.K.O.A.)
| | - Ole L. Nielsen
- Department of Veterinary and Animal Sciences, University of Copenhagen, DK-1870 Copenhagen, Denmark;
| | - Svend B. Jensen
- Department of Nuclear Medicine, Aalborg University Hospital, DK-9000 Aalborg, Denmark;
- Department of Chemistry and Biosciences, Aalborg University, DK-9100 Aalborg, Denmark
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Afzelius P, Nielsen OL, Schønheyder HC, Alstrup A, Hansen SB. An untapped potential for imaging of peripheral osteomyelitis in paediatrics using [ 18F]FDG PET/CT -the inference from a juvenile porcine model. EJNMMI Res 2019; 9:29. [PMID: 30903403 PMCID: PMC6430261 DOI: 10.1186/s13550-019-0498-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 03/11/2019] [Indexed: 12/25/2022] Open
Abstract
PURPOSE To examine parameters affecting the detection of osteomyelitis (OM) by [18F]FDG PET/CT and to reduce tracer activity in a pig model. BACKGROUND [18F]FDG PET/CT is recommended for the diagnosis of OM in the axial skeleton of adults. In children, OM has a tendency to become chronic or recurrent, especially in low-income countries. Early diagnosis and initiation of therapy are therefore essential. We have previously demonstrated that [18F]FDG PET/CT is promising in juvenile Staphylococcus aureus (S. aureus) OM of peripheral bones in a pig model, not failing even small lesions. When using imaging in children, radiation exposure should be balanced against fast diagnostics in the individual case. METHODS Twenty juvenile pigs were inoculated with S. aureus. One week after inoculation, the pigs were [18F]FDG PET/CT scanned. PET list-mode acquired data of a subgroup were retrospectively processed in order to simulate and examine the image quality obtainable with an injected activity of 132 MBq, 44 MBq, 13.2 MBq, and 4.4 MBq, respectively. RESULTS All lesions were detected by [18F]FDG PET and CT. Some lesions were very small (0.01 cm3), and others were larger (4.18 cm3). SUVmax was higher when sequesters (p = 0.023) and fistulas were formed (p < 0.0001). The simulated data demonstrated that it was possible to reduce the activity to 4.4 MBq without compromising image quality in pigs. CONCLUSIONS [18F]FDG PET/CT localized even small OM lesions in peripheral bones. It was possible to reduce the injected activity considerably without compromising image quality, impacting the applicability of PET/CT in peripheral OM in children.
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Affiliation(s)
- P. Afzelius
- Department of Diagnostic Imaging, Section of Clinical Physiology and Nuclear Medicine, North Zealand Hospital, Dyrehavevej 29, 3400 Hillerod, Denmark
- Department of Nuclear Medicine, Aalborg University Hospital, Aalborg, Denmark
| | - O. L. Nielsen
- Department of Veterinary and Animal Science, University of Copenhagen, Copenhagen, Denmark
| | - H. C. Schønheyder
- Department of Clinical Microbiology, Aalborg University Hospital, Aalborg, Denmark
- Department of Clinical Medicine, Aalborg University, Aalborg, Denmark
| | - A.K.O. Alstrup
- Department of Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
| | - S. B. Hansen
- Department of Nuclear Medicine and PET, Aarhus University Hospital, Aarhus, Denmark
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Deidda D, Karakatsanis NA, Robson PM, Calcagno C, Senders ML, Mulder WJM, Fayad ZA, Aykroyd RG, Tsoumpas C. Hybrid PET/MR Kernelised Expectation Maximisation Reconstruction for Improved Image-Derived Estimation of the Input Function from the Aorta of Rabbits. CONTRAST MEDIA & MOLECULAR IMAGING 2019; 2019:3438093. [PMID: 30800014 PMCID: PMC6360049 DOI: 10.1155/2019/3438093] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 11/15/2018] [Accepted: 11/21/2018] [Indexed: 11/30/2022]
Abstract
Positron emission tomography (PET) provides simple noninvasive imaging biomarkers for multiple human diseases which can be used to produce quantitative information from single static images or to monitor dynamic processes. Such kinetic studies often require the tracer input function (IF) to be measured but, in contrast to direct blood sampling, the image-derived input function (IDIF) provides a noninvasive alternative technique to estimate the IF. Accurate estimation can, in general, be challenging due to the partial volume effect (PVE), which is particularly important in preclinical work on small animals. The recently proposed hybrid kernelised ordered subsets expectation maximisation (HKEM) method has been shown to improve accuracy and contrast across a range of different datasets and count levels and can be used on PET/MR or PET/CT data. In this work, we apply the method with the purpose of providing accurate estimates of the aorta IDIF for rabbit PET studies. In addition, we proposed a method for the extraction of the aorta region of interest (ROI) using the MR and the HKEM image, to minimise the PVE within the rabbit aortic region-a method which can be directly transferred to the clinical setting. A realistic simulation study was performed with ten independent noise realisations while two, real data, rabbit datasets, acquired with the Biograph Siemens mMR PET/MR scanner, were also considered. For reference and comparison, the data were reconstructed using OSEM, OSEM with Gaussian postfilter and KEM, as well as HKEM. The results across the simulated datasets and different time frames show reduced PVE and accurate IDIF values for the proposed method, with 5% average bias (0.8% minimum and 16% maximum bias). Consistent results were obtained with the real datasets. The results of this study demonstrate that HKEM can be used to accurately estimate the IDIF in preclinical PET/MR studies, such as rabbit mMR data, as well as in clinical human studies. The proposed algorithm is made available as part of an open software library, and it can be used equally successfully on human or animal data acquired from a variety of PET/MR or PET/CT scanners.
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Affiliation(s)
- Daniel Deidda
- Biomedical Imaging Science Department, University of Leeds, Leeds, UK
- Department of Statistics, University of Leeds, Leeds, UK
| | - Nicolas A. Karakatsanis
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Division of Radiopharmaceutical Sciences, Department of Radiology, Weill Cornell Medical College, Cornell University, New York, NY, USA
| | - Philip M. Robson
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Claudia Calcagno
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Max L. Senders
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Willem J. M. Mulder
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Zahi A. Fayad
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Charalampos Tsoumpas
- Biomedical Imaging Science Department, University of Leeds, Leeds, UK
- Translational and Molecular Imaging Institute (TMII), Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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