1
|
Longo DL, Pirotta E, Gambino R, Romdhane F, Carella A, Corrado A. Tumor pH Imaging Using Chemical Exchange Saturation Transfer (CEST)-MRI. Methods Mol Biol 2023; 2614:287-311. [PMID: 36587132 DOI: 10.1007/978-1-0716-2914-7_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Magnetic resonance imaging (MRI) is a noninvasive imaging technique that allows for physiological and functional studies of the tumor microenvironment. Within MRI, the emerging field of chemical exchange saturation transfer (CEST) has been largely exploited for assessing a salient feature of all solid tumors, extracellular acidosis. Iopamidol-based tumor pH imaging has been demonstrated to provide accurate and high spatial resolution extracellular tumor pH maps to elucidate tumor aggressiveness and for assessing response to therapy, with a high potential for clinical translation. Here, we describe the overall setup and steps for measuring tumor extracellular pH of tumor models in mice by exploiting MRI-CEST pH imaging with a preclinical MRI scanner following the administration of iopamidol. We address issues of pH calibration curve setup, animal handling, pH-responsive contrast agent injection, acquisition protocol, and image processing for accurate quantification and visualization of tumor acidosis.
Collapse
Affiliation(s)
- Dario Livio Longo
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy.
| | - Elisa Pirotta
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy
| | - Riccardo Gambino
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Feriel Romdhane
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy
| | - Antonella Carella
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy
| | - Alessia Corrado
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy
| |
Collapse
|
2
|
Longo DL, Irrera P, Consolino L, Sun PZ, McMahon MT. Renal pH Imaging Using Chemical Exchange Saturation Transfer (CEST) MRI: Basic Concept. Methods Mol Biol 2021; 2216:241-256. [PMID: 33476004 DOI: 10.1007/978-1-0716-0978-1_14] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023]
Abstract
Magnetic Resonance Imaging (MRI) has been actively explored in the last several decades for assessing renal function by providing several physiological information, including glomerular filtration rate, renal plasma flow, tissue oxygenation and water diffusion. Within MRI, the developing field of chemical exchange saturation transfer (CEST) has potential to provide further functional information for diagnosing kidney diseases. Both endogenous produced molecules as well as exogenously administered CEST agents have been exploited for providing functional information related to kidney diseases in preclinical studies. In particular, CEST MRI has been exploited for assessing the acid-base homeostasis in the kidney and for monitoring pH changes in several disease models. This review summarizes several CEST MRI procedures for assessing kidney functionality and pH, for monitoring renal pH changes in different kidney injury models and for evaluating renal allograft rejection.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.
Collapse
Affiliation(s)
- Dario Livio Longo
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy.
| | - Pietro Irrera
- University of Campania "Luigi Vanvitelli", Napoli, Italy
| | - Lorena Consolino
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Phillip Zhe Sun
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Michael T McMahon
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, USA
- Division of MR Research, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| |
Collapse
|
3
|
Pedersen M, Irrera P, Dastrù W, Zöllner FG, Bennett KM, Beeman SC, Bretthorst GL, Garbow JR, Longo DL. Dynamic Contrast Enhancement (DCE) MRI-Derived Renal Perfusion and Filtration: Basic Concepts. Methods Mol Biol 2021; 2216:205-227. [PMID: 33476002 DOI: 10.1007/978-1-0716-0978-1_12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Dynamic contrast-enhanced (DCE) MRI monitors the transit of contrast agents, typically gadolinium chelates, through the intrarenal regions, the renal cortex, the medulla, and the collecting system. In this way, DCE-MRI reveals the renal uptake and excretion of the contrast agent. An optimal DCE-MRI acquisition protocol involves finding a good compromise between whole-kidney coverage (i.e., 3D imaging), spatial and temporal resolution, and contrast resolution. By analyzing the enhancement of the renal tissues as a function of time, one can determine indirect measures of clinically important single-kidney parameters as the renal blood flow, glomerular filtration rate, and intrarenal blood volumes. Gadolinium-containing contrast agents may be nephrotoxic in patients suffering from severe renal dysfunction, but otherwise DCE-MRI is clearly useful for diagnosis of renal functions and for assessing treatment response and posttransplant rejection.Here we introduce the concept of renal DCE-MRI, describe the existing methods, and provide an overview of preclinical DCE-MRI applications to illustrate the utility of this technique to measure renal perfusion and glomerular filtration rate in animal models.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction is complemented by two separate publications describing the experimental procedure and data analysis.
Collapse
Affiliation(s)
- Michael Pedersen
- Department of Clinical Medicine - Comparative Medicine Lab, Aarhus University, Aarhus, Denmark
| | - Pietro Irrera
- University of Campania "Luigi Vanvitelli", Napoli, Italy
| | - Walter Dastrù
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, Italy
| | - Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Kevin M Bennett
- Washington University School of Medicine, St. Louis, MO, USA
| | - Scott C Beeman
- Washington University School of Medicine, St. Louis, MO, USA
| | | | - Joel R Garbow
- Washington University School of Medicine, St. Louis, MO, USA
| | - Dario Livio Longo
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Torino, Italy.
| |
Collapse
|
4
|
Anemone A, Consolino L, Arena F, Capozza M, Longo DL. Imaging tumor acidosis: a survey of the available techniques for mapping in vivo tumor pH. Cancer Metastasis Rev 2020; 38:25-49. [PMID: 30762162 PMCID: PMC6647493 DOI: 10.1007/s10555-019-09782-9] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cancer cells are characterized by a metabolic shift in cellular energy production, orchestrated by the transcription factor HIF-1α, from mitochondrial oxidative phosphorylation to increased glycolysis, regardless of oxygen availability (Warburg effect). The constitutive upregulation of glycolysis leads to an overproduction of acidic metabolic products, resulting in enhanced acidification of the extracellular pH (pHe ~ 6.5), which is a salient feature of the tumor microenvironment. Despite the importance of pH and tumor acidosis, there is currently no established clinical tool available to image the spatial distribution of tumor pHe. The purpose of this review is to describe various imaging modalities for measuring intracellular and extracellular tumor pH. For each technique, we will discuss main advantages and limitations, pH accuracy and sensitivity of the applied pH-responsive probes and potential translatability to the clinic. Particular attention is devoted to methods that can provide pH measurements at high spatial resolution useful to address the task of tumor heterogeneity and to studies that explored tumor pH imaging for assessing treatment response to anticancer therapies.
Collapse
Affiliation(s)
- Annasofia Anemone
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy
| | - Lorena Consolino
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy
| | - Francesca Arena
- Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Via Nizza 52, Turin, Italy.,Center for Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Ribes 5, Colleretto Giacosa, Italy
| | - Martina Capozza
- Center for Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Ribes 5, Colleretto Giacosa, Italy
| | - Dario Livio Longo
- Molecular Imaging Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, Turin, Italy. .,Institute of Biostructures and Bioimaging (IBB), Italian National Research Council (CNR), Via Nizza 52, Turin, Italy.
| |
Collapse
|
5
|
Gholami L, Tafaghodi M, Abbasi B, Daroudi M, Kazemi Oskuee R. Preparation of superparamagnetic iron oxide/doxorubicin loaded chitosan nanoparticles as a promising glioblastoma theranostic tool. J Cell Physiol 2018; 234:1547-1559. [DOI: 10.1002/jcp.27019] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 06/25/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Leila Gholami
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences Mashhad Iran
- Department of Modern Sciences and Technologies Faculty of Medicine, Mashhad University of Medical Sciences Mashhad Iran
| | - Mohsen Tafaghodi
- Nanotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences Mashhad Iran
| | - Bita Abbasi
- Department of Radiology Mashhad University of Medical Sciences Mashhad Iran
| | - Majid Daroudi
- Department of Modern Sciences and Technologies Faculty of Medicine, Mashhad University of Medical Sciences Mashhad Iran
- Nuclear Medicine Research Center (NMRC), Mashhad University of Medical Sciences Mashhad Iran
| | - Reza Kazemi Oskuee
- Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences Mashhad Iran
- Department of Medical Biotechnology Faculty of Medicine, Mashhad University of Medical Sciences Mashhad Iran
| |
Collapse
|
6
|
Arena F, Irrera P, Consolino L, Colombo Serra S, Zaiss M, Longo DL. Flip-angle based ratiometric approach for pulsed CEST-MRI pH imaging. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2018; 287:1-9. [PMID: 29272735 DOI: 10.1016/j.jmr.2017.12.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/14/2017] [Accepted: 12/09/2017] [Indexed: 06/07/2023]
Abstract
Several molecules have been exploited for developing MRI pH sensors based on the chemical exchange saturation transfer (CEST) technique. A ratiometric approach, based on the saturation of two exchanging pools at the same saturation power, or by varying the saturation power levels on the same pool, is usually needed to rule out the concentration term from the pH measurement. However, all these methods have been demonstrated by using a continuous wave saturation scheme that limits its translation to clinical scanners. This study shows a new ratiometric CEST-MRI pH-mapping approach based on a pulsed CEST saturation scheme for a radiographic contrast agent (iodixanol) possessing a single chemical exchange site. This approach is based on the ratio of the CEST contrast effects at two different flip angles combinations (180°/360° and 180°/720°), keeping constant the mean irradiation RF power (Bavg power). The proposed ratiometric approach index is concentration independent and it showed good pH sensitivity and accuracy in the physiological range between 6.0 and 7.4.
Collapse
Affiliation(s)
- Francesca Arena
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Pietro Irrera
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Lorena Consolino
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | | | - Moritz Zaiss
- Department of High-field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Tübingen, Germany
| | - Dario Livio Longo
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy; Consiglio Nazionale delle Ricerche (CNR), Istituto di Biostrutture e Bioimmagini, Torino, Italy.
| |
Collapse
|
7
|
Sanjai C, Kothan S, Gonil P, Saesoo S, Sajomsang W. Super-paramagnetic loaded nanoparticles based on biological macromolecules for in vivo targeted MR imaging. Int J Biol Macromol 2016; 86:233-41. [PMID: 26783640 DOI: 10.1016/j.ijbiomac.2016.01.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/13/2016] [Accepted: 01/13/2016] [Indexed: 02/07/2023]
Abstract
Target-specific MRI contrast agent based on super-paramagnetic iron oxide-chitosan-folic acid (SPIONP-CS-FA) nanoparticles was fabricated by using an ionotropic gelation method, which involved the loading of SPIONPs at various concentrations into CS-FA nanoparticles by electrostatic interaction. The SPIONP-CS-FA nanoparticles were characterized by ATR-FTIR, XRD, TEM, and VSM techniques. This study revealed that the advantages of this system would be green fabrication, low cytotoxicity at iron concentrations ranging from 0.52 mg/L to 4.16 mg/L, and high water stability (pH 6) at 4°C over long periods. Average particle size and positive zeta-potential of the SPIONP-CS-FA nanoparticles was found to be 130 nm with narrow size distribution and 42 mV, respectively. In comparison to SPIONP-0.5-CS nanoparticles, SPIONP-0.5-CS-FA nanoparticles showed higher and specific cellular uptake levels into human cervical adenocarcinoma cells due to the presence of folate receptors, while in vivo results (Wistar rat) indicated that only liver tissue showed significant decreases in MR image intensity on T2 weighted images and T2* weighted images after post-injection, in comparison with other organs. Our results demonstrated that SPIONP-CS-FA nanoparticles can be applied as an either tumor or organ specific MRI contrast agents.
Collapse
Affiliation(s)
- Chutimon Sanjai
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Suchart Kothan
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
| | - Pattarapond Gonil
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency, Thailand Science Park, Pathum Thani 10120, Thailand
| | - Somsak Saesoo
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency, Thailand Science Park, Pathum Thani 10120, Thailand
| | - Warayuth Sajomsang
- National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency, Thailand Science Park, Pathum Thani 10120, Thailand.
| |
Collapse
|
8
|
Comprehensive prediction of drug-protein interactions and side effects for the human proteome. Sci Rep 2015; 5:11090. [PMID: 26057345 PMCID: PMC4603786 DOI: 10.1038/srep11090] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 05/14/2015] [Indexed: 01/23/2023] Open
Abstract
Identifying unexpected drug-protein interactions is crucial for drug repurposing. We develop a comprehensive proteome scale approach that predicts human protein targets and side effects of drugs. For drug-protein interaction prediction, FINDSITE(comb), whose average precision is ~30% and recall ~27%, is employed. For side effect prediction, a new method is developed with a precision of ~57% and a recall of ~24%. Our predictions show that drugs are quite promiscuous, with the average (median) number of human targets per drug of 329 (38), while a given protein interacts with 57 drugs. The result implies that drug side effects are inevitable and existing drugs may be useful for repurposing, with only ~1,000 human proteins likely causing serious side effects. A killing index derived from serious side effects has a strong correlation with FDA approved drugs being withdrawn. Therefore, it provides a pre-filter for new drug development. The methodology is free to the academic community on the DR. PRODIS (DRugome, PROteome, and DISeasome) webserver at http://cssb.biology.gatech.edu/dr.prodis/. DR. PRODIS provides protein targets of drugs, drugs for a given protein target, associated diseases and side effects of drugs, as well as an interface for the virtual target screening of new compounds.
Collapse
|
9
|
Longo DL, Sun PZ, Consolino L, Michelotti FC, Uggeri F, Aime S. A general MRI-CEST ratiometric approach for pH imaging: demonstration of in vivo pH mapping with iobitridol. J Am Chem Soc 2014; 136:14333-6. [PMID: 25238643 PMCID: PMC4210149 DOI: 10.1021/ja5059313] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Chemical exchange saturation transfer
(CEST) is a novel contrast
mechanism for magnetic resonance imaging (MRI). CEST MRI selectively
saturates exchangeable protons that are transferred to MRI-detectable
bulk water signal. MRI-CEST (pH)-responsive agents are probes able
to map pH in the microenvironment in which they distribute. To minimize
the confounding effects of contrast agent concentration, researchers
have developed ratiometric CEST imaging, which investigates contrast
agents containing multiple magnetically non-equivalent proton groups,
whose prototropic exchange have different pH responses. However, conventional
ratiometric CEST MRI imposes stringent requirements on the selection
of CEST contrasts agents. In this study, a novel ratiometric pH MRI
method based on the analysis of CEST effects under different radio
frequency irradiation power levels was developed. The proposed method
has been demonstrated using iobitridol, an X-ray contrast agent analog
of iopamidol but containing a single set of amide protons, both in vitro and in vivo.
Collapse
Affiliation(s)
- Dario L Longo
- Institute of Biostructures and Bioimages (CNR) c/o Molecular Biotechnology Center and §Department of Molecular Biotechnology and Health Sciences, Molecular Imaging Center, University of Torino , Torino 10126, Italy
| | | | | | | | | | | |
Collapse
|
10
|
Sanjai C, Kothan S, Gonil P, Saesoo S, Sajomsang W. Chitosan-triphosphate nanoparticles for encapsulation of super-paramagnetic iron oxide as an MRI contrast agent. Carbohydr Polym 2014; 104:231-7. [PMID: 24607182 DOI: 10.1016/j.carbpol.2014.01.012] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2013] [Revised: 01/01/2014] [Accepted: 01/03/2014] [Indexed: 02/07/2023]
Abstract
Super-paramagnetic iron oxide nanoparticles (SPIONPs) were encapsulated at various concentrations within chitosan-triphosphate (SPIONPs-CS) nanoparticles using an ionotropic gelation method. The encapsulation of SPIONPs within CS nanoparticles enhanced their dispersion ability in aqueous solution, with all particles being lower than 130 nm in size and having highly positive surface charge. The SPIONPs-CS nanoparticles exhibited crystalline structure and super-paramagnetic behavior, as seen in non-encapsulated SPIONPs. The morphology of SPIONPs-CS nanoparticles showed that they almost spherical in shape. The effect of phantom environments (culture medium and 3% agar solution) on either T1 or T2 weighted MRI was investigated using a clinical 1.5T MRI scanner. The results revealed that 3% agar solution showed relaxation values higher than the culture medium, leading to a significant decrease in the MR image intensity. Our results demonstrated that the SPIONPs-CS nanoparticles can be applied as tissue-specific MRI contrast agents.
Collapse
Affiliation(s)
- Chutimon Sanjai
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Suchart Kothan
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
| | - Pattarapond Gonil
- Nanodelivery System Laboratory, National Nanotechnology Center, National Science and Technology Development Agency, Pathumthani, 10120, Thailand
| | - Somsak Saesoo
- Nanodelivery System Laboratory, National Nanotechnology Center, National Science and Technology Development Agency, Pathumthani, 10120, Thailand
| | - Warayuth Sajomsang
- Nanodelivery System Laboratory, National Nanotechnology Center, National Science and Technology Development Agency, Pathumthani, 10120, Thailand.
| |
Collapse
|
11
|
Strategies for optimizing water-exchange rates of lanthanide-based contrast agents for magnetic resonance imaging. Molecules 2013; 18:9352-81. [PMID: 23921796 PMCID: PMC3775326 DOI: 10.3390/molecules18089352] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 11/16/2022] Open
Abstract
This review describes recent advances in strategies for tuning the water-exchange rates of contrast agents for magnetic resonance imaging (MRI). Water-exchange rates play a critical role in determining the efficiency of contrast agents; consequently, optimization of water-exchange rates, among other parameters, is necessary to achieve high efficiencies. This need has resulted in extensive research efforts to modulate water-exchange rates by chemically altering the coordination environments of the metal complexes that function as contrast agents. The focus of this review is coordination-chemistry-based strategies used to tune the water-exchange rates of lanthanide(III)-based contrast agents for MRI. Emphasis will be given to results published in the 21st century, as well as implications of these strategies on the design of contrast agents.
Collapse
|