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Yeh LY, Fang YT, Lee HS, Liu CH, Chen YY, Lo YC, Laiman V, Liou JP, Chung KF, Chuang HC, Lin CH. A Potent Histone Deacetylase Inhibitor MPT0E028 Mitigates Emphysema Severity via Components of the Hippo Signaling Pathway in an Emphysematous Mouse Model. Front Med (Lausanne) 2022; 9:794025. [PMID: 35665319 PMCID: PMC9157428 DOI: 10.3389/fmed.2022.794025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 04/21/2022] [Indexed: 11/21/2022] Open
Abstract
Background Chronic obstructive pulmonary disease (COPD) is a major cause of chronic mortality. The objective of this study was to investigate the therapeutic potential of a novel potent histone deacetylase (HDAC) inhibitor MPT0E028 on emphysema. Materials and Methods A mouse model of porcine pancreatic elastase (PPE)-induced emphysema was orally administered 0, 25, or 50 mg/kg body weight (BW) of the MPT0E028 five times/week for 3 weeks. Pulmonary function, mean linear intercept (MLI), chest CT, inflammation, yes-associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ), surfactant protein C (SPC), T1-α, p53, and sirtuin 1 (SIRT1) levels were examined. Results 50 mg/kg BW of the MPT0E028 significantly decreased the tidal volume in emphysematous mice (p < 0.05). Emphysema severity was significantly reduced from 26.65% (PPE only) to 13.83% (50 mg/kg BW of the MPT0E028). Total cell counts, neutrophils, lymphocytes, and eosinophils significantly decreased with both 25 and 50 mg/kg BW of the MPT0E028 (p < 0.05). Also, 50 mg/kg BW of the MPT0E028 significantly decreased the levels of KC, TNF-α, and IL-6 in lung tissues and serum (p < 0.05). Expressions of p-TAZ/TAZ in lung tissues significantly decreased with 50 mg/kg BW of the MPT0E028 (p < 0.05). Expressions of p53 significantly decreased in alveolar regions with 50 mg/kg BW of the MPT0E028 (p < 0.05), and the expression of SPC increased in alveolar regions with 50 mg/kg BW of the MPT0E028 (p < 0.05). Conclusions Our study showed that the potent HDAC inhibitor MPT0E028 reduced the severity and inflammation of emphysema with improvement in lung function, which could be regulated by Hippo signaling pathway. The MPT0E028 may have therapeutic potential for emphysema.
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Affiliation(s)
- Lu-Yang Yeh
- School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yu-Ting Fang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hong-Sheng Lee
- Graduate Institute of Medical Science, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Chia-Hao Liu
- Graduate Institute of Medical Science, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - You-Yin Chen
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yu-Chun Lo
- PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Vincent Laiman
- International PhD Program in Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Department of Anatomical Pathology, Faculty of Medicine, Public Health, and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Jing-Ping Liou
- School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan
| | - Kian Fan Chung
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Hsiao-Chi Chuang
- School of Respiratory Therapy, College of Medicine, Taipei Medical University, Taipei, Taiwan
- Division of Pulmonary Medicine, Department of Internal Medicine, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
- Cell Physiology and Molecular Image Research Center, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
- *Correspondence: Hsiao-Chi Chuang
| | - Chien-Huang Lin
- Graduate Institute of Medical Science, College of Medicine, Taipei Medical University, Taipei, Taiwan
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Burkhardt R, Gora T, Fingerle AA, Sauter AP, Meurer F, Gassert FT, Dobiasch S, Schilling D, Feuchtinger A, Walch AK, Multhoff G, Herzen J, Noël PB, Rummeny EJ, Combs SE, Schmid TE, Pfeiffer F, Wilkens JJ. In-vivo X-ray dark-field computed tomography for the detection of radiation-induced lung damage in mice. Phys Imaging Radiat Oncol 2021; 20:11-16. [PMID: 34611553 PMCID: PMC8476771 DOI: 10.1016/j.phro.2021.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 09/13/2021] [Accepted: 09/13/2021] [Indexed: 11/22/2022] Open
Abstract
Radiation-induced lung damage was observed using X-ray dark-field tomography. In this pre-clinical study, mouse lungs were irradiated and subsequently imaged. We report increased sensitivity of X-ray dark-field tomography over absorption-based tomography.
Background and Purpose Radiotherapy of thoracic tumours can lead to side effects in the lung, which may benefit from early diagnosis. We investigated the potential of X-ray dark-field computed tomography by a proof-of-principle murine study in a clinically relevant radiotherapeutic setting aiming at the detection of radiation-induced lung damage. Material and Methods Six mice were irradiated with 20 Gy to the entire right lung. Together with five unirradiated control mice, they were imaged using computed tomography with absorption and dark-field contrast before and 16 weeks post irradiation. Mean pixel values for the right and left lung were calculated for both contrasts, and the right-to-left-ratio R of these means was compared. Radiologists also assessed the tomograms acquired 16 weeks post irradiation. Sensitivity, specificity, inter- and intra-reader accuracy were evaluated. Results In absorption contrast the group-average of R showed no increase in the control group and increased by 7% (p = 0.005) in the irradiated group. In dark-field contrast, it increased by 2% in the control group and by 14% (p = 0.005) in the irradiated group. Specificity was 100% for both contrasts but sensitivity was almost four times higher using dark-field tomography. Two cases were missed by absorption tomography but were detected by dark-field tomography. Conclusions The applicability of X-ray dark-field computed tomography for the detection of radiation-induced lung damage was demonstrated in a pre-clinical mouse model. The presented results illustrate the differences between dark-field and absorption contrast and show that dark-field tomography could be advantageous in future clinical settings.
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Affiliation(s)
- Rico Burkhardt
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany.,Physics Department, Technical University of Munich, Garching, Germany
| | - Thomas Gora
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Alexander A Fingerle
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Andreas P Sauter
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Felix Meurer
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Florian T Gassert
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Sophie Dobiasch
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Daniela Schilling
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Annette Feuchtinger
- Abteilung Analytische Pathologie, Helmholtz Zentrum München, Neuherberg, Germany
| | - Axel K Walch
- Abteilung Analytische Pathologie, Helmholtz Zentrum München, Neuherberg, Germany
| | - Gabriele Multhoff
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany.,TranslaTUM, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Julia Herzen
- Physics Department, Technical University of Munich, Garching, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany.,Munich School of BioEngineering (MSB), Technical University of Munich, Garching, Germany
| | - Peter B Noël
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Ernst J Rummeny
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Stephanie E Combs
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany.,Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site Munich, Munich, Germany
| | - Thomas E Schmid
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Franz Pfeiffer
- Physics Department, Technical University of Munich, Garching, Germany.,Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany.,Munich School of BioEngineering (MSB), Technical University of Munich, Garching, Germany
| | - Jan J Wilkens
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Physics Department, Technical University of Munich, Garching, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany
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Badea CT. Principles of Micro X-ray Computed Tomography. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00006-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Burkhardt R, Gora T, Fingerle AA, Sauter AP, Meurer F, Umkehrer S, von Teuffenbach M, Kampfer S, Schilling D, Feuchtinger A, Walch AK, Rummeny E, Combs SE, Schmid TE, Pfeiffer F, Wilkens JJ, Herzen J. Early detection of radiation-induced lung damage with X-ray dark-field radiography in mice. Eur Radiol 2020; 31:4175-4183. [PMID: 33211140 PMCID: PMC8128748 DOI: 10.1007/s00330-020-07459-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 10/12/2020] [Accepted: 11/03/2020] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Assessing the advantage of x-ray dark-field contrast over x-ray transmission contrast in radiography for the detection of developing radiation-induced lung damage in mice. METHODS Two groups of female C57BL/6 mice (irradiated and control) were imaged obtaining both contrasts monthly for 28 weeks post irradiation. Six mice received 20 Gy of irradiation to the entire right lung sparing the left lung. The control group of six mice was not irradiated. A total of 88 radiographs of both contrasts were evaluated for both groups based on average values for two regions of interest, covering (irradiated) right lung and healthy left lung. The ratio of these average values, R, was distinguished between healthy and damaged lungs for both contrasts. The time-point when deviations of R from healthy lung exceeded 3σ was determined and compared among contrasts. The Wilcoxon-Mann-Whitney test was used to test against the null hypothesis that there is no difference between both groups. A selection of 32 radiographs was assessed by radiologists. Sensitivity and specificity were determined in order to compare the diagnostic potential of both contrasts. Inter-reader and intra-reader accuracy were rated with Cohen's kappa. RESULTS Radiation-induced morphological changes of lung tissue caused deviations from the control group that were measured on average 10 weeks earlier with x-ray dark-field contrast than with x-ray transmission contrast. Sensitivity, specificity, and accuracy doubled using dark-field radiography. CONCLUSION X-ray dark-field radiography detects morphological changes of lung tissue associated with radiation-induced damage earlier than transmission radiography in a pre-clinical mouse model. KEY POINTS • Significant deviations from healthy lung due to irradiation were measured after 16 weeks with x-ray dark-field radiography (p = 0.004). • Significant deviations occur on average 10 weeks earlier for x-ray dark-field radiography in comparison to x-ray transmission radiography. • Sensitivity and specificity doubled when using x-ray dark-field radiography instead of x-ray transmission radiography.
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Affiliation(s)
- Rico Burkhardt
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany. .,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany. .,Physics Department, Technical University of Munich, Garching, Germany.
| | - Thomas Gora
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Alexander A Fingerle
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Andreas P Sauter
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Felix Meurer
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Stephan Umkehrer
- Chair of Biomedical Physics, Technical University of Munich, Garching, Germany
| | | | - Severin Kampfer
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Physics Department, Technical University of Munich, Garching, Germany
| | - Daniela Schilling
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Annette Feuchtinger
- Abteilung Analytische Pathologie, Helmholtz Zentrum München, Neuherberg, Germany
| | - Axel K Walch
- Abteilung Analytische Pathologie, Helmholtz Zentrum München, Neuherberg, Germany
| | - Ernst Rummeny
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany
| | - Stephanie E Combs
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany.,Deutsches Konsortium für Translationale Krebsforschung (DKTK), Partner Site Munich, Munich, Germany
| | - Thomas E Schmid
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Institute of Radiation Medicine (IRM), Helmholtz Zentrum München, Neuherberg, Germany
| | - Franz Pfeiffer
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany.,Munich School of BioEngineering (MSB), Technical University of Munich, Garching, Germany
| | - Jan J Wilkens
- Department of Radiation Oncology, Technical University of Munich, School of Medicine and Klinikum rechts der Isar, Munich, Germany.,Physics Department, Technical University of Munich, Garching, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany
| | - Julia Herzen
- Physics Department, Technical University of Munich, Garching, Germany.,Chair of Biomedical Physics, Technical University of Munich, Garching, Germany.,Munich School of BioEngineering (MSB), Technical University of Munich, Garching, Germany
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Gradl R, Dierolf M, Hehn L, Günther B, Yildirim AÖ, Gleich B, Achterhold K, Pfeiffer F, Morgan KS. Propagation-based Phase-Contrast X-ray Imaging at a Compact Light Source. Sci Rep 2017; 7:4908. [PMID: 28687726 PMCID: PMC5501835 DOI: 10.1038/s41598-017-04739-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 05/18/2017] [Indexed: 11/09/2022] Open
Abstract
We demonstrate the applicability of propagation-based X-ray phase-contrast imaging at a laser-assisted compact light source with known phantoms and the lungs and airways of a mouse. The Munich Compact Light Source provides a quasi-monochromatic beam with partial spatial coherence, and high flux relative to other non-synchrotron sources (up to 1010 ph/s). In our study we observe significant edge-enhancement and quantitative phase-retrieval is successfully performed on the known phantom. Furthermore the images of a small animal show the potential for live bio-imaging research studies that capture biological function using short exposures.
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Affiliation(s)
- Regine Gradl
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany. .,Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany. .,Institute for Advanced Studies, Technical University of Munich, Lichtenbergstrasse 2 a, 85748, Garching, Germany.
| | - Martin Dierolf
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany
| | - Lorenz Hehn
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, München, Germany
| | - Benedikt Günther
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany.,Max-Plank-Institute for Quantum Optics, Hans-Kopfermannstr. 1, 85748, Garching, Germany
| | - Ali Önder Yildirim
- Comprehensive Pneumologie Center (CPC), Institute of Lung Biology and Disease, Helmholtz Zentrum München, Member of the German Lung Center for Lung Research (DZL), Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Bernhard Gleich
- Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany
| | - Klaus Achterhold
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany
| | - Franz Pfeiffer
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Munich School of BioEngineering, Technical University of Munich, Boltzmannstr. 11, 85748, Garching, Germany.,Institute for Advanced Studies, Technical University of Munich, Lichtenbergstrasse 2 a, 85748, Garching, Germany.,Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, München, Germany
| | - Kaye Susannah Morgan
- Chair of Biomedical Physics, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748, Garching, Germany.,Institute for Advanced Studies, Technical University of Munich, Lichtenbergstrasse 2 a, 85748, Garching, Germany.,School of Physics and Astronomy, Monash University, Clayton, Victoria, 3800, Australia
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PAULINI FERNANDA, CHAVES SACHAB, RÔLO JOSÉLUIZJ, AZEVEDO RICARDOBDE, LUCCI CAROLINAM. Evaluation of ovarian structures using computerized microtomography. ACTA ACUST UNITED AC 2017; 89:2131-2139. [DOI: 10.1590/0001-3765201720150864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 06/22/2016] [Indexed: 12/19/2022]
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Abstract
Modern imaging technology, now utilized in most biomedical research areas (bioimaging), enables the detection and visualization of biological processes at various levels of the molecule, organelle, cell, tissue, organ and/or whole body. In toxicologic pathology, the impact of modern imaging technology is becoming apparent from digital histopathology to novel molecular imaging for in vivo studies. This overview summarizes recent progresses in digital microscopy imaging and newly developed digital slide techniques. Applications of virtual microscopy imaging are discussed and compared to traditional optical microscopy reading. New generation digital pathology approaches, including automatic slide inspection, digital slide databases and image management are briefly introduced. Commonly used in vivo preclinical imaging technologies are also summarized. While most of these new imaging techniques are still undergoing rapid development, it is important that toxicologic pathologists embrace and utilize these technologies as advances occur.
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Affiliation(s)
- Xiaoyou Ying
- Drug Safety Evaluation, sanofi-aventis, Bridgewater, New Jersey 08807-0800, USA.
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9
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Ashton JR, West JL, Badea CT. In vivo small animal micro-CT using nanoparticle contrast agents. Front Pharmacol 2015; 6:256. [PMID: 26581654 PMCID: PMC4631946 DOI: 10.3389/fphar.2015.00256] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/19/2015] [Indexed: 12/12/2022] Open
Abstract
Computed tomography (CT) is one of the most valuable modalities for in vivo imaging because it is fast, high-resolution, cost-effective, and non-invasive. Moreover, CT is heavily used not only in the clinic (for both diagnostics and treatment planning) but also in preclinical research as micro-CT. Although CT is inherently effective for lung and bone imaging, soft tissue imaging requires the use of contrast agents. For small animal micro-CT, nanoparticle contrast agents are used in order to avoid rapid renal clearance. A variety of nanoparticles have been used for micro-CT imaging, but the majority of research has focused on the use of iodine-containing nanoparticles and gold nanoparticles. Both nanoparticle types can act as highly effective blood pool contrast agents or can be targeted using a wide variety of targeting mechanisms. CT imaging can be further enhanced by adding spectral capabilities to separate multiple co-injected nanoparticles in vivo. Spectral CT, using both energy-integrating and energy-resolving detectors, has been used with multiple contrast agents to enable functional and molecular imaging. This review focuses on new developments for in vivo small animal micro-CT using novel nanoparticle probes applied in preclinical research.
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Affiliation(s)
- Jeffrey R Ashton
- Department of Biomedical Engineering, Duke University, Durham NC, USA ; Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
| | - Jennifer L West
- Department of Biomedical Engineering, Duke University, Durham NC, USA
| | - Cristian T Badea
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
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Bianchi A, Tibiletti M, Kjørstad Å, Birk G, Schad LR, Stierstorfer B, Rasche V, Stiller D. Three-dimensional accurate detection of lung emphysema in rats using ultra-short and zero echo time MRI. NMR IN BIOMEDICINE 2015; 28:1471-1479. [PMID: 26403226 DOI: 10.1002/nbm.3417] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 08/10/2015] [Accepted: 08/26/2015] [Indexed: 06/05/2023]
Abstract
Emphysema is a life-threatening pathology that causes irreversible destruction of alveolar walls. In vivo imaging techniques play a fundamental role in the early non-invasive pre-clinical and clinical detection and longitudinal follow-up of this pathology. In the present study, we aimed to evaluate the feasibility of using high resolution radial three-dimensional (3D) zero echo time (ZTE) and 3D ultra-short echo time (UTE) MRI to accurately detect lung pathomorphological changes in a rodent model of emphysema.Porcine pancreas elastase (PPE) was intratracheally administered to the rats to produce the emphysematous changes. 3D ZTE MRI, low and high definition 3D UTE MRI and micro-computed tomography images were acquired 4 weeks after the PPE challenge. Signal-to-noise ratios (SNRs) were measured in PPE-treated and control rats. T2* values were computed from low definition 3D UTE MRI. Histomorphometric measurements were made after euthanizing the animals. Both ZTE and UTE MR images showed a significant decrease in the SNR measured in PPE-treated lungs compared with controls, due to the pathomorphological changes taking place in the challenged lungs. A significant decrease in T2* values in PPE-challenged animals compared with controls was measured using UTE MRI. Histomorphometric measurements showed a significant increase in the mean linear intercept in PPE-treated lungs. UTE yielded significantly higher SNR compared with ZTE (14% and 30% higher in PPE-treated and non-PPE-treated lungs, respectively).This study showed that optimized 3D radial UTE and ZTE MRI can provide lung images of excellent quality, with high isotropic spatial resolution (400 µm) and SNR in parenchymal tissue (>25) and negligible motion artifacts in freely breathing animals. These techniques were shown to be useful non-invasive instruments to accurately and reliably detect the pathomorphological alterations taking place in emphysematous lungs, without incurring the risks of cumulative radiation exposure typical of micro-computed tomography.
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Affiliation(s)
- Andrea Bianchi
- Boehringer Ingelheim Pharma GmbH & Co. KG, Target Discovery Research, In-Vivo Imaging Laboratory, Biberach an der Riss, Germany
| | - Marta Tibiletti
- Core Facility Small Animal MRI, Ulm University, Ulm, Germany
| | - Åsmund Kjørstad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
- Department of Neuroradiology, University Hospital Hamburg-Eppendorf, Germany
| | - Gerald Birk
- Boehringer Ingelheim Pharma GmbH & Co. KG, Target Discovery Research, Target Validation Technologies, Biberach an der Riss, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Birgit Stierstorfer
- Boehringer Ingelheim Pharma GmbH & Co. KG, Target Discovery Research, Target Validation Technologies, Biberach an der Riss, Germany
| | - Volker Rasche
- Core Facility Small Animal MRI, Ulm University, Ulm, Germany
- Department of Internal Medicine II, Ulm University, Ulm, Germany
| | - Detlef Stiller
- Boehringer Ingelheim Pharma GmbH & Co. KG, Target Discovery Research, In-Vivo Imaging Laboratory, Biberach an der Riss, Germany
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Holm AT, Wulf-Johansson H, Hvidsten S, Jorgensen PT, Schlosser A, Pilecki B, Ormhøj M, Moeller JB, Johannsen C, Baun C, Andersen T, Schneider JP, Hegermann J, Ochs M, Götz AA, Schulz H, de Angelis MH, Vestbo J, Holmskov U, Sorensen GL. Characterization of spontaneous air space enlargement in mice lacking microfibrillar-associated protein 4. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1114-24. [PMID: 26033354 DOI: 10.1152/ajplung.00351.2014] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 03/25/2015] [Indexed: 11/22/2022] Open
Abstract
Microfibrillar-associated protein 4 (MFAP4) is localized to elastic fibers in blood vessels and the interalveolar septa of the lungs and is further present in bronchoalveolar lavage. Mfap4 has been previously suggested to be involved in elastogenesis in the lung. We tested this prediction and aimed to characterize the pulmonary function changes and emphysematous changes that occur in Mfap4-deficient (Mfap4(-/-)) mice. Significant changes included increases in total lung capacity and compliance, which were evident in Mfap4(-/-) mice at 6 and 8 mo but not at 3 mo of age. Using in vivo breath-hold gated microcomputed tomography (micro-CT) in 8-mo-old Mfap4(-/-) mice, we found that the mean density of the lung parenchyma was decreased, and the low-attenuation area (LAA) was significantly increased by 14% compared with Mfap4(+/+) mice. Transmission electron microscopy (TEM) did not reveal differences in the organization of elastic fibers, and there was no difference in elastin content, but a borderline significant increase in elastin mRNA expression in 3-mo-old mice. Stereological analysis showed that alveolar surface density in relation to the lung parenchyma and total alveolar surface area inside of the lung were both significantly decreased in Mfap4(-/-) mice by 25 and 15%, respectively. The data did not support an essential role of MFAP4 in pulmonary elastic fiber organization or content but indicated increased turnover in young Mfap4(-/-) mice. However, Mfap4(-/-) mice developed a spontaneous loss of lung function, which was evident at 6 mo of age, and moderate air space enlargement, with emphysema-like changes.
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Affiliation(s)
- Anne Trommelholt Holm
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Helle Wulf-Johansson
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Svend Hvidsten
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Patricia Troest Jorgensen
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Anders Schlosser
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Bartosz Pilecki
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Maria Ormhøj
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Jesper Bonnet Moeller
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Claus Johannsen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Christina Baun
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Thomas Andersen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Jan Philipp Schneider
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany; and REBIRTH Cluster of Excellence, Hannover, Germany
| | - Jan Hegermann
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany; and REBIRTH Cluster of Excellence, Hannover, Germany
| | - Matthias Ochs
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany; Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany; and REBIRTH Cluster of Excellence, Hannover, Germany
| | - Alexander A Götz
- Institute of Neuropathology, University of Göttingen, Göttingen, Germany
| | - Holger Schulz
- Institute of Lung Biology and Disease, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; and Member of the German Center for Lung Research (DZL), Hannover, Germany; Institute of Epidemiology I, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Martin Hrabě de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany; Chair of Experimental Genetics, Center of Life and Food Sciences Weihenstephan, Technische Universität München, Freising-Weihenstephan, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; and
| | - Jørgen Vestbo
- Department of Respiratory Medicine, Gentofte Hospital, Hellerup, Denmark
| | - Uffe Holmskov
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Grith Lykke Sorensen
- Institute of Molecular Medicine, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark;
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Clark DP, Badea CT. Micro-CT of rodents: state-of-the-art and future perspectives. Phys Med 2014; 30:619-34. [PMID: 24974176 PMCID: PMC4138257 DOI: 10.1016/j.ejmp.2014.05.011] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/15/2014] [Accepted: 05/28/2014] [Indexed: 02/06/2023] Open
Abstract
Micron-scale computed tomography (micro-CT) is an essential tool for phenotyping and for elucidating diseases and their therapies. This work is focused on preclinical micro-CT imaging, reviewing relevant principles, technologies, and applications. Commonly, micro-CT provides high-resolution anatomic information, either on its own or in conjunction with lower-resolution functional imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). More recently, however, advanced applications of micro-CT produce functional information by translating clinical applications to model systems (e.g., measuring cardiac functional metrics) and by pioneering new ones (e.g. measuring tumor vascular permeability with nanoparticle contrast agents). The primary limitations of micro-CT imaging are the associated radiation dose and relatively poor soft tissue contrast. We review several image reconstruction strategies based on iterative, statistical, and gradient sparsity regularization, demonstrating that high image quality is achievable with low radiation dose given ever more powerful computational resources. We also review two contrast mechanisms under intense development. The first is spectral contrast for quantitative material discrimination in combination with passive or actively targeted nanoparticle contrast agents. The second is phase contrast which measures refraction in biological tissues for improved contrast and potentially reduced radiation dose relative to standard absorption imaging. These technological advancements promise to develop micro-CT into a commonplace, functional and even molecular imaging modality.
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Affiliation(s)
- D P Clark
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA
| | - C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA.
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13
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Gammon ST, Foje N, Brewer EM, Owers E, Downs CA, Budde MD, Leevy WM, Helms MN. Preclinical anatomical, molecular, and functional imaging of the lung with multiple modalities. Am J Physiol Lung Cell Mol Physiol 2014; 306:L897-914. [DOI: 10.1152/ajplung.00007.2014] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In vivo imaging is an important tool for preclinical studies of lung function and disease. The widespread availability of multimodal animal imaging systems and the rapid rate of diagnostic contrast agent development have empowered researchers to noninvasively study lung function and pulmonary disorders. Investigators can identify, track, and quantify biological processes over time. In this review, we highlight the fundamental principles of bioluminescence, fluorescence, planar X-ray, X-ray computed tomography, magnetic resonance imaging, and nuclear imaging modalities (such as positron emission tomography and single photon emission computed tomography) that have been successfully employed for the study of lung function and pulmonary disorders in a preclinical setting. The major principles, benefits, and applications of each imaging modality and technology are reviewed. Limitations and the future prospective of multimodal imaging in pulmonary physiology are also discussed. In vivo imaging bridges molecular biological studies, drug design and discovery, and the imaging field with modern medical practice, and, as such, will continue to be a mainstay in biomedical research.
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Affiliation(s)
- Seth T. Gammon
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Nathan Foje
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Elizabeth M. Brewer
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
| | - Elizabeth Owers
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - Charles A. Downs
- Nell Hodgson Woodruff School of Nursing, Emory University, Atlanta, Georgia; and
| | - Matthew D. Budde
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - W. Matthew Leevy
- Department of Biological Sciences, Notre Dame Integrated Imaging Facility, Notre Dame, Indiana
| | - My N. Helms
- Department of Pediatrics Center for Cystic Fibrosis and Airways Disease Research, Emory University, Atlanta, Georgia
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Detection and early phase assessment of radiation-induced lung injury in mice using micro-CT. PLoS One 2012; 7:e45960. [PMID: 23029340 PMCID: PMC3454347 DOI: 10.1371/journal.pone.0045960] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 08/27/2012] [Indexed: 12/25/2022] Open
Abstract
Radiation therapy is an important therapeutic modality for thoracic malignancies. However, radiation-induced pulmonary injuries such as radiation pneumonitis and fibrosis are major dose-limiting factors. Previous research shows that micro-computed tomography (micro-CT) can detect radiation-induced lung injuries a few months following irradiation, but studies to assess the early response of lung tissue are lacking. The aim of this study was to determine if micro-CT could be used to detect and assess early-phase radiation–induced lung injury in mice. Twenty-one animals were divided into three groups: normal (n = 7), one day after x-ray exposure (n = 7), and at four days after x-ray exposure (n = 7). The x-ray-exposed groups received a single dose of 20 Gy, to the whole lung. Histology showed enlargements of the air space (Lm: mean chord length) following irradiation. 40.5±3.8 µm and 60.0±6.9 µm were observed after one and four days, respectively, compared to 26.5±3.1 µm in normal mice. Three-dimensional micro-CT images were constructed and histograms of radiodensity - Hounsfield Units (HU) - were used to assess changes in mouse lungs. Radiation-induced lung injury was observed in irradiated mice, by the use of two parameters which were defined as shifts in peak HU between −200 to −800 HU (PeakHU) and increase in the number of pixels at −1000 HU (Number-1000). These parameters were correlated with histological changes. The results demonstrate that micro-CT can be used for the early detection and assessment of structural and histopathological changes resulting from radiation-induced lung injury in mice. Micro-CT has the advantage, over traditional histological techniques, of allowing longitudinal studies of lung disease progression and assessment of the entire lung, while reducing the number of animals required for such studies.
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15
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Zurek M, Boyer L, Caramelle P, Boczkowski J, Crémillieux Y. Longitudinal and noninvasive assessment of emphysema evolution in a murine model using proton MRI. Magn Reson Med 2011; 68:898-904. [DOI: 10.1002/mrm.23281] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 10/02/2011] [Accepted: 10/11/2011] [Indexed: 11/06/2022]
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16
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Eisa F, Brauweiler R, Hupfer M, Nowak T, Lotz L, Hoffmann I, Wachter D, Dittrich R, Beckmann MW, Jost G, Pietsch H, Kalender WA. Dynamic contrast-enhanced micro-CT on mice with mammary carcinoma for the assessment of antiangiogenic therapy response. Eur Radiol 2011; 22:900-7. [PMID: 22071777 DOI: 10.1007/s00330-011-2318-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Revised: 09/29/2011] [Accepted: 10/15/2011] [Indexed: 12/17/2022]
Abstract
OBJECTIVE To evaluate the potential of in vivo dynamic contrast-enhanced micro-computed tomography (DCE micro-CT) for the assessment of antiangiogenic drug therapy response of mice with mammary carcinoma. METHODS 20 female mice with implanted MCF7 tumours were split into control group and therapy group treated with a known effective antiangiogenic drug. All mice underwent DCE micro-CT for the 3D analysis of functional parameters (relative blood volume [rBV], vascular permeability [K], area under the time-enhancement curve [AUC]) and morphology. All parameters were determined for total, peripheral and central tumour volumes of interest (VOIs). Immunohistochemistry was performed to characterise tumour vascularisation. 3D dose distributions were determined. RESULTS The mean AUCs were significantly lower in therapy with P values of 0.012, 0.007 and 0.023 for total, peripheral and central tumour VOIs. K and rBV showed significant differences for the peripheral (P(per)(K) = 0.032, P(per) (rBV) = 0.029), but not for the total and central tumour VOIs (P(total)(K) = 0.108, P(central)(K) = 0.246, P(total) (rBV) = 0.093, P(central) (rBV) = 0.136). Mean tumour volume was significantly smaller in therapy (P (in vivo) = 0.001, P (ex vivo) = 0.005). Histology revealed greater vascularisation in the controls and central tumour necrosis. Doses ranged from 150 to 300 mGy. CONCLUSIONS This study indicates the great potential of DCE micro-CT for early in vivo assessment of antiangiogenic drug therapy response. KEY POINTS Dynamic contrast enhanced micro-CT (computed tomography) is a new experimental laboratory technique. DCE micro-CT allows early in vivo assessment of antiangiogenic drug therapy response. Pharmaceutical drugs can be tested before translation to clinical practice. Both morphological and functional parameters can be obtained using DCE micro-CT. Antiangiogenic effects can be visualised with DCE micro-CT.
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Affiliation(s)
- Fabian Eisa
- Institute of Medical Physics, University of Erlangen-Nuremberg, Henkest. 91, 91052, Erlangen, Germany.
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Sandhu GS, Solorio L, Broome AM, Salem N, Kolthammer J, Shah T, Flask C, Duerk JL. Whole animal imaging. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2010; 2:398-421. [PMID: 20836038 DOI: 10.1002/wsbm.71] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Translational research plays a vital role in understanding the underlying pathophysiology of human diseases, and hence development of new diagnostic and therapeutic options for their management. After creating an animal disease model, pathophysiologic changes and effects of a therapeutic intervention on them are often evaluated on the animals using immunohistologic or imaging techniques. In contrast to the immunohistologic techniques, the imaging techniques are noninvasive and hence can be used to investigate the whole animal, oftentimes in a single exam which provides opportunities to perform longitudinal studies and dynamic imaging of the same subject, and hence minimizes the experimental variability, requirement for the number of animals, and the time to perform a given experiment. Whole animal imaging can be performed by a number of techniques including x-ray computed tomography, magnetic resonance imaging, ultrasound imaging, positron emission tomography, single photon emission computed tomography, fluorescence imaging, and bioluminescence imaging, among others. Individual imaging techniques provide different kinds of information regarding the structure, metabolism, and physiology of the animal. Each technique has its own strengths and weaknesses, and none serves every purpose of image acquisition from all regions of an animal. In this review, a broad overview of basic principles, available contrast mechanisms, applications, challenges, and future prospects of many imaging techniques employed for whole animal imaging is provided. Our main goal is to briefly describe the current state of art to researchers and advanced students with a strong background in the field of animal research.
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Affiliation(s)
- Gurpreet Singh Sandhu
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Luis Solorio
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Ann-Marie Broome
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Nicolas Salem
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jeff Kolthammer
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Tejas Shah
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Chris Flask
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jeffrey L Duerk
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
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Namati E, Thiesse J, Sieren JC, Ross A, Hoffman EA, McLennan G. Longitudinal assessment of lung cancer progression in the mouse using in vivo micro-CT imaging. Med Phys 2010; 37:4793-805. [PMID: 20964199 DOI: 10.1118/1.3476454] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Small animal micro-CT imaging is being used increasingly in preclinical biomedical research to provide phenotypic descriptions of genomic models. Most of this imaging is coincident with animal death and is used to show the extent of disease as an end point. Longitudinal imaging overcomes the limitation of single time-point imaging because it enables tracking of the natural history of disease and provides qualitative and, where possible, quantitative assessments of the effects of an intervention. The pulmonary system is affected by many disease conditions, such as lung cancer, chronic obstructive pulmonary disease, asthma, and granulomatous disorders. Noninvasive imaging can accurately assess the lung phenotype within the living animal, evaluating not only global lung measures, but also regional pathology. However, imaging the lung in the living animal is complicated by rapid respiratory motion, which leads to image based artifacts. Furthermore, no standard mouse lung imaging protocols exist for longitudinal assessment, with each group needing to develop their own systematic approach. METHODS In this article, the authors present an outline for performing longitudinal breath-hold gated micro-CT imaging for the assessment of lung nodules in a mouse model of lung cancer. The authors describe modifications to the previously published intermittent isopressure breath-hold technique including a new animal preparation and anesthesia protocol, implementation of a ring artifact reduction, variable scanner geometry, and polynomial beam hardening correction. In addition, the authors describe a multitime-point data set registration and tumor labeling and tracking strategy. RESULTS In vivo micro-CT data sets were acquired at months 2, 3, and 4 posturethane administration in cancer mice (n = 5) and simultaneously in control mice (n = 3). 137 unique lung nodules were identified from the cancer mice while no nodules were detected in the control mice. A total of 411 nodules were segmented and labeled over the three time-points. Lung nodule metrics including RECIST, Ortho, WHO, and 3D volume were determined and extracted. A tumor incidence rate of 30.44 +/- 1.93 SEM for n = 5 was found with identification of nodules as small as 0.11 mm (RECIST) and as large as 1.66 mm (RECIST). In addition, the tumor growth and doubling rate between months 2-3 and 3-4 were calculated. Here, the growth rate was slightly higher in the second period based on the 3D volume data (0.12 +/- 0.13 to 0.13 +/- 0.17 microl) but significantly less based on the linear diameter metrics [RECIST (0.33 +/- 0.19 to 0.17 +/- 0.18 mm); Ortho (0.24 +/- 0.15 to 0.16 +/- 0.15 mm)], indicating the need to understand how each metric is obtained and how to correctly interpret change in tumor size. CONCLUSIONS In conclusion, micro-CT imaging provides a unique platform for in vivo longitudinal assessment of pulmonary lung cancer progression and potentially tracking of therapies at very high resolutions. The ability to evaluate the same subject over time provides for a sensitive assay that can be carried out on a smaller sample size. When integrated with image processing and analysis routines as detailed in this study, the data acquired from micro-CT imaging can now provide a very powerful assessment of pulmonary disease outcomes.
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Affiliation(s)
- Eman Namati
- Department of Internal Medicine, University of Iowa, Iowa City, Iowa 52242, USA; School of Computer Science, Engineering and Mathematics, Flinders University, Adelaide 5042, Australia.
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Artaechevarria X, Blanco D, de Biurrun G, Ceresa M, Pérez-Martín D, Bastarrika G, de Torres JP, Zulueta JJ, Montuenga LM, Ortiz-de-Solorzano C, Munoz-Barrutia A. Evaluation of micro-CT for emphysema assessment in mice: comparison with non-radiological techniques. Eur Radiol 2010; 21:954-62. [PMID: 20953986 DOI: 10.1007/s00330-010-1982-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 08/30/2010] [Accepted: 09/09/2010] [Indexed: 12/24/2022]
Abstract
OBJECTIVES To define the potential, limitations and synergies of micro-CT and other non-radiological techniques for the quantification of emphysema and related processes in mice, by performing a complete characterization of the elastase-induced emphysema model. MATERIALS AND METHODS Ninety A/J mice (45 treated and 45 controls) were studied at different time points using breath-hold gated micro-CT, functional test parameters, RT-PCR for RNA cytokine expression, Luminex technology for cytokine plasma concentration and histomorphometry. RESULTS Both histomorphometry and micro-CT imaging reflect rapid initial emphysema progression followed by steady-state development at decreasing rates. Cytokine measurements reveal an acute inflammatory response within the first 24 h that disappears after the first week. Limited systemic effect was observed based on plasma cytokine concentration. Lung compliance decreases during the acute inflammation phase and increases afterwards. CONCLUSION Histomorphometry is the most sensitive technique since it detects airspace enlargement before the other methods (1 h after treatment). Micro-CT correlates well with histology (r2 = 0.63) proving appropriate for longitudinal studies. Functional test parameters do not necessarily correlate with the extent of emphysema, as they can be influenced by acute inflammation. Finally, cytokine measurements correlate with the presence of inflammation in histology but not with emphysema.
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Affiliation(s)
- Xabier Artaechevarria
- Cancer Imaging Laboratory, Oncology Division, Center for Applied Medical Research, University of Navarra, 55 Pio XII, 31008 Pamplona, Spain.
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Venkatasamy R, Spina D. Protease inhibitors in respiratory disease: focus on asthma and chronic obstructive pulmonary disease. Expert Rev Clin Immunol 2010; 3:365-81. [PMID: 20477680 DOI: 10.1586/1744666x.3.3.365] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Respiratory diseases, such as asthma and chronic obstructive pulmonary disease (COPD), are a major health burden on society and current treatment modalities for these diseases have not significantly changed over the past 40 years. The only major pharmacological advancement for the treatment of these diseases has been to increase the duration of action of bronchodilators (asthma: salmeterol; COPD: tiotropium bromide) and glucocorticosteroids (asthma: fluticasone propionate) and, increasingly, to formulate these agents in the same delivery device. Despite our increasing understanding of the cell and molecular biology of these diseases, the development of novel treatments remains beyond the reach of the scientific community. Proteases are a family of proteins with diverse biological activity, which are found in abundance within the airways of asthma and COPD, and have been implicated in the pathogenesis of these diseases. The targeting of proteases, including mast cell tryptase, neutrophil elastase and matrix metalloprotease with low-molecular-weight inhibitors, has highlighted the potential role of these enzymes in mediating certain aspects of the disease process in preclinical studies. Several challenges remain regarding the development of protease inhibitors, including the synthesis of highly potent and specific inhibitors, and target validation in man.
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Affiliation(s)
- Radhakrishnan Venkatasamy
- King's College London, Sackler Institute of Pulmonary Pharmacology, School of Biomedical and Health Science, Pharmaceutical Science Research Division, Guy's Campus, London SE1 1UL, UK.
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Badea CT, Johnston SM, Subashi E, Qi Y, Hedlund LW, Johnson GA. Lung perfusion imaging in small animals using 4D micro-CT at heartbeat temporal resolution. Med Phys 2010; 37:54-62. [PMID: 20175466 DOI: 10.1118/1.3264619] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Quantitative in vivo imaging of lung perfusion in rodents can provide critical information for preclinical studies. However, the combined challenges of high temporal and spatial resolution have made routine quantitative perfusion imaging difficult in small animals. The purpose of this work is to demonstrate 4D micro-CT for perfusion imaging in rodents at heartbeat temporal resolution and isotropic spatial resolution. METHODS We have recently developed a dual tube/detector micro-CT scanner that is well suited to capture first pass kinetics of a bolus of contrast agent used to compute perfusion information. Our approach is based on the paradigm that similar time density curves can be reproduced in a number of consecutive, small volume injections of iodinated contrast agent at a series of different angles. This reproducibility is ensured by the high-level integration of the imaging components of our system with a microinjector, a mechanical ventilator, and monitoring applications. Sampling is controlled through a biological pulse sequence implemented in LABVIEW. Image reconstruction is based on a simultaneous algebraic reconstruction technique implemented on a graphic processor unit. The capabilities of 4D micro-CT imaging are demonstrated in studies on lung perfusion in rats. RESULTS We report 4D micro-CT imaging in the rat lung with a heartbeat temporal resolution (approximately 150 ms) and isotropic 3D reconstruction with a voxel size of 88 microm based on sampling using 16 injections of 50 microL each. The total volume of contrast agent injected during the experiments (0.8 mL) was less than 10% of the total blood volume in a rat. This volume was not injected in a single bolus, but in multiple injections separated by at least 2 min interval to allow for clearance and adaptation. We assessed the reproducibility of the time density curves with multiple injections and found that these are very similar. The average time density curves for the first eight and last eight injections are slightly different, i.e., for the last eight injections, both the maximum of the average time density curves and its area under the curve are decreased by 3.8% and 7.2%, respectively, relative to the average time density curves based on the first eight injections. The radiation dose associated with our 4D micro-CT imaging is 0.16 Gy and is therefore in the range of a typical micro-CT dose. CONCLUSIONS 4D micro-CT-based perfusion imaging demonstrated here has immediate application in a wide range of preclinical studies such as tumor perfusion, angiogenesis, and renal function. Although our imaging system is in many ways unique, we believe that our approach based on the multiple injection paradigm can be used with the newly developed flat-panel slip-ring-based micro-CT to increase their temporal resolution in dynamic perfusion studies.
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Affiliation(s)
- Cristian T Badea
- Center for In Vivo Microscopy, Box 3302, Duke University Medical Center, Durham, North Carolina 27710, USA.
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Artaechevarria X, Pérez-Martín D, Ceresa M, de Biurrun G, Blanco D, Montuenga LM, van Ginneken B, Ortiz-de-Solorzano C, Muñoz-Barrutia A. Airway segmentation and analysis for the study of mouse models of lung disease using micro-CT. Phys Med Biol 2009; 54:7009-24. [PMID: 19887716 DOI: 10.1088/0031-9155/54/22/017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Animal models of lung disease are gaining importance in understanding the underlying mechanisms of diseases such as emphysema and lung cancer. Micro-CT allows in vivo imaging of these models, thus permitting the study of the progression of the disease or the effect of therapeutic drugs in longitudinal studies. Automated analysis of micro-CT images can be helpful to understand the physiology of diseased lungs, especially when combined with measurements of respiratory system input impedance. In this work, we present a fast and robust murine airway segmentation and reconstruction algorithm. The algorithm is based on a propagating fast marching wavefront that, as it grows, divides the tree into segments. We devised a number of specific rules to guarantee that the front propagates only inside the airways and to avoid leaking into the parenchyma. The algorithm was tested on normal mice, a mouse model of chronic inflammation and a mouse model of emphysema. A comparison with manual segmentations of two independent observers shows that the specificity and sensitivity values of our method are comparable to the inter-observer variability, and radius measurements of the mainstem bronchi reveal significant differences between healthy and diseased mice. Combining measurements of the automatically segmented airways with the parameters of the constant phase model provides extra information on how disease affects lung function.
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Affiliation(s)
- X Artaechevarria
- Cancer Imaging Laboratory, Center for Applied Medical Research, 31008 Pamplona, Spain.
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Abstract
COPD is a highly prevalent disorder that results from the interplay of genetic susceptibility and environmental exposures. Over the past 2 decades, significant technological advances have been made in genetic investigations of complex diseases, yet limited progress has been made in the identification of additional COPD susceptibility genes. Genetic and phenotypic heterogeneity, limited power due to modest study population sizes, and significant modification of genetic effects by environmental factors pose significant challenges in COPD and emphysema genetic studies. More refined characterization of the emphysema and airway components of COPD can now be obtained through the systematic use of CT scans. These improved phenotypes can be applied in genome-wide association studies and will likely lead to the discovery of additional susceptibility loci and therapeutic targets.
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Affiliation(s)
- Emily S Wan
- Channing Laboratory and the Pulmonary and Critical Care Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - Edwin K Silverman
- Channing Laboratory and the Pulmonary and Critical Care Division, Department of Medicine, Brigham and Women's Hospital, Boston, MA.
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24
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Postnov AA, D'Haese PC, Neven E, De Clerck NM, Persy VP. Possibilities and limits of X-ray microtomography for in vivo and ex vivo detection of vascular calcifications. Int J Cardiovasc Imaging 2009; 25:615-24. [PMID: 19363656 DOI: 10.1007/s10554-009-9459-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Accepted: 03/25/2009] [Indexed: 10/20/2022]
Abstract
In the present paper, vascular calcifications due to chronic renal failure in rats are studied by X-ray microtomography (micro-CT). Although micro-CT is traditionally used as an imaging technique, a quantitative analysis of data obtained by in vivo and ex vivo micro-CT is described and discussed. By comparison with traditional destructive methods, such as histomorphometry and atomic absorption, the detection limits for calcium were determined in living rats and in extracted aortas. micro-CT proved to be an effective non-invasive imaging technique allowing non-destructive quantification of ectopic calcifications.
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Affiliation(s)
- A A Postnov
- Laboratory of Microtomography, University of Antwerp, Universiteitsplein 1, Campus Drie Eiken, Antwerp, Belgium.
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25
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Kawakami M, Matsuo Y, Yoshiura K, Nagase T, Yamashita N. Sequential and quantitative analysis of a murine model of elastase-induced emphysema. Biol Pharm Bull 2008; 31:1434-8. [PMID: 18591788 DOI: 10.1248/bpb.31.1434] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Emphysema, one of chronic obstructive pulmonary disease (COPD), is characterized as destruction of airway wall and small airway inflammation. To assess the kinetics of disease progression in murine model of elastase-induced emphysema, we used micro-computed tomography (CT) compared with morphological changes. Two week after elastase administration, a significant increase in the volume of low-density areas, recognized as -800--600 Hounsfield units by micro-CT, was observed. Coefficient of correlation between mean linear intercept (Lm) and low-density area examined by CT, was 0.79 (p<0.01). Micro-CT can quantitatively and sequentially detect murine emphysematous changes, offering a practical method to sequentially analyze the therapeutic effects of treatments in a murine model of emphysema.
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Affiliation(s)
- Masaki Kawakami
- Department of Pharmatherapy, Research Institute of Pharmaceutical Sciences, Musashino University, Tokyo, Japan
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26
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Badea CT, Drangova M, Holdsworth DW, Johnson GA. In vivo small-animal imaging using micro-CT and digital subtraction angiography. Phys Med Biol 2008; 53:R319-50. [PMID: 18758005 DOI: 10.1088/0031-9155/53/19/r01] [Citation(s) in RCA: 215] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Small-animal imaging has a critical role in phenotyping, drug discovery and in providing a basic understanding of mechanisms of disease. Translating imaging methods from humans to small animals is not an easy task. The purpose of this work is to review in vivo x-ray based small-animal imaging, with a focus on in vivo micro-computed tomography (micro-CT) and digital subtraction angiography (DSA). We present the principles, technologies, image quality parameters and types of applications. We show that both methods can be used not only to provide morphological, but also functional information, such as cardiac function estimation or perfusion. Compared to other modalities, x-ray based imaging is usually regarded as being able to provide higher throughput at lower cost and adequate resolution. The limitations are usually associated with the relatively poor contrast mechanisms and potential radiation damage due to ionizing radiation, although the use of contrast agents and careful design of studies can address these limitations. We hope that the information will effectively address how x-ray based imaging can be exploited for successful in vivo preclinical imaging.
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Affiliation(s)
- C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University, Durham, NC 27710, USA
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27
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Abstract
OBJECTIVES Implementation and evaluation of retrospective respiratory and cardiac gating of mice and rats using a flat-panel volume-CT prototype (fpVCT). MATERIALS AND METHODS Respiratory and cardiac gating was implemented by equipping a fpVCT with a small animal monitoring unit. ECG and breathing excursions were recorded and 2 binary gating signals derived. Mice and rats were scanned continuously over 80 seconds after administration of blood-pool contrast media. Projections were chosen to reconstruct volumes that fall within defined phases of the cardiac/respiratory cycle. RESULTS Multireader analysis indicated that in gated still images motion artifacts were strongly reduced and diaphragm, tracheobronchial tract, heart, and vessels sharply delineated. From 4D series, functional data such as respiratory tidal volume and cardiac ejection fraction were calculated and matched well with values known from literature. DISCUSSION Implementation of retrospective gating in fpVCT improves image quality and opens new perspectives for functional cardiac and lung imaging in small animals.
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28
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Shofer S, Badea C, Auerbach S, Schwartz DA, Johnson GA. A micro-computed tomography-based method for the measurement of pulmonary compliance in healthy and bleomycin-exposed mice. Exp Lung Res 2007; 33:169-83. [PMID: 17558678 PMCID: PMC2677683 DOI: 10.1080/01902140701364458] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Micro-computed tomography (microCT) is being increasingly used to examine small animal models of pulmonary injury. The authors have developed a microCT technique suitable for the determination of pulmonary compliance in injured mice. Lung volumes in normal mice were radiographically determined at end-inspiration and end-expiration and pulmonary compliance was calculated at 2 time points 2 weeks apart, whereas a second group of mice were given bleomycin and imaged 3 weeks following drug administration. Compliance measurements were validated using a commercially available ventilator system. MicroCT pulmonary compliance measurements are suitable for longitudinal measurements, and correlate with physiologic measurements of pulmonary compliance.
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Affiliation(s)
- Scott Shofer
- Pulmonary, Allergy, and Critical Care, Duke University Medical Center, Durham, North Carolina 27710, USA.
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29
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30
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Scadeng M, Rossiter HB, Dubowitz DJ, Breen EC. High-Resolution Three-Dimensional Magnetic Resonance Imaging of Mouse Lung In Situ. Invest Radiol 2007; 42:50-7. [PMID: 17213749 DOI: 10.1097/01.rli.0000248850.13221.61] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES This study establishes a method for high-resolution isotropic magnetic resonance (MR) imaging of mouse lungs using tracheal liquid-instillation to remove MR susceptibility artifacts. METHODS C57BL/6J mice were instilled sequentially with perfluorocarbon and phosphate-buffered saline to an airway pressure of 10, 20, or 30 cm H2O. Imaging was performed in a 7T MR scanner using a 2.5-cm Quadrature volume coil and a 3-dimensional (3D) FLASH imaging sequence. RESULTS Liquid-instillation removed magnetic susceptibility artifacts and allowed lung structure to be viewed at an isotropic resolution of 78-90 microm. Instilled liquid and modeled lung volumes were well correlated (R = 0.92; P < 0.05) and differed by a constant tissue volume (220 +/- 92 microL). 3D image renderings allowed differences in structural dimensions (volumes and areas) to be accurately measured at each inflation pressure. CONCLUSION These data demonstrate the efficacy of pulmonary liquid instillation for in situ high-resolution MR imaging of mouse lungs for accurate measurement of pulmonary airway, parenchymal, and vascular structures.
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Affiliation(s)
- Miriam Scadeng
- Department of Radiology, Center for Functional Magnetic Resonance Imaging, University of California, San Diego, La Jolla, California 92093, USA
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31
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Namati E, Chon D, Thiesse J, Hoffman EA, de Ryk J, Ross A, McLennan G. In vivo micro-CT lung imaging via a computer-controlled intermittent iso-pressure breath hold (IIBH) technique. Phys Med Biol 2006; 51:6061-75. [PMID: 17110770 DOI: 10.1088/0031-9155/51/23/008] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Respiratory research with mice using micro-computed tomography (micro-CT) has been predominantly hindered by the limited resolution and signal-to-noise ratio (SNR) as a result of respiratory motion artefacts. In this study, we develop a novel technique for capturing the lung microstructure in vivo using micro-CT, through a computer-controlled intermittent iso-pressure breath hold (IIBH), to reduce respiratory motion, increasing resolution and SNR of reconstructed images. We compare four gating techniques, i.e. no gating, late expiratory (LE) gating, late inspiratory (LI) gating and finally intermittent iso-pressure breath hold (IIBH) gating. Quantitatively, we compare several common image analysis methods used to extract valuable physiologic and anatomic information from the respiratory system, and show that the IIBH technique produces the most representative and repeatable results.
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Affiliation(s)
- E Namati
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA
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32
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Persy V, Postnov A, Neven E, Dams G, De Broe M, D'Haese P, De Clerck N. High-Resolution X-Ray Microtomography Is a Sensitive Method to Detect Vascular Calcification in Living Rats With Chronic Renal Failure. Arterioscler Thromb Vasc Biol 2006; 26:2110-6. [PMID: 16840714 DOI: 10.1161/01.atv.0000236200.02726.f7] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Chronic renal failure (CRF) is associated with a 10- to 20-fold increase in cardiovascular risk. Vascular calcification is a prominent feature of cardiovascular disease in patients with end-stage renal failure and contributes to the excess mortality in this population. In this study, we explored in vivo X-ray microtomography (micro-CT) as a tool to detect and follow-up vascular calcifications in the aorta of living rats with adenine-induced CRF. METHODS AND RESULTS With in vivo micro-CT, calcification of the aorta in uremic rats was clearly discernible on transversal virtual cross-sections. Micro-CT findings correlated well with tissue calcium content and histology. Repetitive scans in animals with light, moderate, and severe vascular calcification showed good reproducibility with minimal interference of motion artifacts. Moreover, both calcified volume and area could be quantified with this method. CONCLUSIONS In vivo micro-CT scanning is a sensitive method to detect vascular calcifications in CRF rats, allowing follow-up and quantification of the development, and potential reversal during treatment, of vascular calcifications in living animals.
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Affiliation(s)
- Veerle Persy
- University of Antwerp, Department of Pathophysiology, Universiteitsplein 1, T 3.06, B-2610 Antwerp, Belgium.
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