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Sherif MF, Abu Alghar MI, Alshafe MH, Badra AG. Assessment of acute renal allograft dysfunction by MRI diffusion techniques. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2018. [DOI: 10.1016/j.ejrnm.2018.06.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Egger C, Cannet C, Gérard C, Debon C, Stohler N, Dunbar A, Tigani B, Li J, Beckmann N. Adriamycin-induced nephropathy in rats: Functional and cellular effects characterized by MRI. J Magn Reson Imaging 2014; 41:829-40. [DOI: 10.1002/jmri.24603] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 02/05/2014] [Indexed: 01/21/2023] Open
Affiliation(s)
- Christine Egger
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
- University of Basel; Biocenter; Basel Switzerland
| | - Catherine Cannet
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
| | - Christelle Gérard
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
| | - Corinne Debon
- Novartis Institutes for BioMedical Research; Autoimmune Diseases; Transplantation & Inflammation Department; Basel Switzerland
| | - Nadine Stohler
- Novartis Institutes for BioMedical Research; Autoimmune Diseases; Transplantation & Inflammation Department; Basel Switzerland
| | - Andrew Dunbar
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
| | - Bruno Tigani
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
| | - Jianping Li
- Novartis Institutes for BioMedical Research; Autoimmune Diseases; Transplantation & Inflammation Department; Basel Switzerland
| | - Nicolau Beckmann
- Novartis Institutes for BioMedical Research; Analytical Sciences and Imaging; Basel Switzerland
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Abstract
PURPOSE OF REVIEW Pretransplant assessment of kidney graft viability may help clinicians to decide whether to accept or discard a kidney for transplantation. With the increasing demand for donor kidneys and the increased use of marginal kidneys, the need of viability markers has increased to pursue superior transplant outcomes. Hypothermic machine perfusion (HMP) provides the theoretical opportunity to assess the viability of donor kidneys. We discuss the novel developments in viability testing during HMP and address the future prospects. RECENT FINDINGS HMP viability testing has focused on the analysis of machine perfusion parameters and perfusate biomarkers. Renal resistance and the biomarkers lactate dehydrogenase, aspartate transaminase, glutathione-S-transferase, N-acetyl-β-D-glucosaminidase, heart-type fatty acid binding protein, lipid peroxidation products, redox-active iron and IL-18 are correlated with transplant outcome in terms of development of delayed graft function or graft survival. However, they all lack adequate predictive value for transplant outcome. New techniques including contrast-enhanced ultrasound, three-dimensional ultrasound and magnetic resonance spectrometry are promising methods to test kidney viability during HMP, but their value has to be established. The introduction of normothermic machine perfusion offers other promising opportunities for viability testing. SUMMARY Machine perfusion characteristics and perfusate biomarkers have been extensively studied. They often correlate with the transplant outcome, but the present viability tests are not reliable predictors of transplant outcome. New developments in kidney graft viability assessment are necessary to have a chance of being clinically useful in the future.
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Magnetic resonance spectroscopic methods for the assessment of metabolic functions in the diseased brain. Curr Top Behav Neurosci 2011; 11:169-98. [PMID: 22076698 DOI: 10.1007/7854_2011_166] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Magnetic resonance spectroscopy (MRS) is a non-invasive technique that can be used to detect and quantify multiple metabolites. This chapter will review some of the applications of MRS to the study of brain functions. Typically, (1)H-MRS can detect metabolites reflecting neuronal density and integrity, markers of energy metabolism or inflammation, as well as neurotransmitters. The complexity of the proton spectrum has however led to the development of other nuclei-based methods, such as (31)P- and (13)C-MRS, which offer a broader chemical shift range and therefore can provide more detailed information at the level of single metabolites. The versatility of MRS allows for a wide range of clinical applications, of which neurodegeneration is an interesting target for spectroscopy-based studies. In particular, MRS can identify patterns of altered brain chemistry in Alzheimer's patients and can help establish differential diagnosis in Alzheimer's and Parkinson's diseases. Using MRS to follow less abundant neurotransmitters is currently out of reach and will most likely depend on the development of methods such as hyperpolarization that can increase the sensitivity of detection. In particular, dynamic nuclear polarization has opened up a new and exciting area of medical research, with developments that could greatly impact on the real-time monitoring of in vivo metabolic processes in the brain.
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Pieper GM, Shah A, Harmann L, Cooley BC, Ionova IA, Migrino RQ. Speckle-tracking 2-dimensional strain echocardiography: a new noninvasive imaging tool to evaluate acute rejection in cardiac transplantation. J Heart Lung Transplant 2010; 29:1039-46. [PMID: 20488730 DOI: 10.1016/j.healun.2010.04.009] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/03/2010] [Accepted: 04/07/2010] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND There remains no reliable non-invasive method to detect cardiac transplant rejection. Recently, speckle-tracking 2-dimensional strain echocardiography (2DSE) was shown to be sensitive in the early detection of myocardial dysfunction in various models of cardiomyopathy. We aim to determine if 2DSE-derived functional indices can detect cardiac transplant rejection. METHODS Heterotopic rat cardiac transplantation was performed in histocompatible isografts or histoincompatible allografts. Histologic rejection scores were determined. Short-axis, mid-left ventricular (LV) echocardiography was performed on Day 6 after transplantation. Conventional measures of function were measured, (including LV fractional shortening and ejection fraction) as well as 2DSE parameters. RESULTS Despite class IIIB rejection in allografts and no rejection in isografts, there was no difference between isografts vs allografts in fractional shortening (15% +/- 3% vs 12% +/- 3%) or ejection fraction (36% +/- 5% vs 26% +/- 6%; both not significant). In contrast, 2DSE revealed decreases between isografts and allografts in global radial strain (12.6% +/- 5.6% vs 1.1% +/- 0.2%, p < 0.05), peak radial systolic strain rate (3.10 +/- 0.74/s vs 0.54 +/- 0.13/s, p < 0.001), and peak circumferential systolic strain rate (-1.99 +/- 0.55 vs -0.43 +/- 0.11/s; p < 0.01). CONCLUSIONS Systolic strain imaging using 2DSE differentiates myocardial function between experimental cardiac transplant rejection in allografts and non-rejection in isografts. Therefore, 2DSE may be useful in early non-invasive detection of transplant rejection.
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Affiliation(s)
- Galen M Pieper
- Department of Surgery (Transplant Surgery), Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
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Use of magnetic resonance imaging contrast agents to detect transplanted liver cells. Top Magn Reson Imaging 2010; 20:113-20. [PMID: 20010066 DOI: 10.1097/rmr.0b013e3181c0dfe4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Liver transplantation saves the lives of millions of patients every year. The advent of cell rather than organ transplantation could potentially further improve the success of this approach. However, one problem facing the delivery and the monitoring of cell transplants is their noninvasive in vivo visualization. Noninvasive imaging is needed for this. To distinguish transplanted cells from the host liver, it is necessary to either tag these using exogenous contrast agents (eg, iron oxide nanoparticles) or insert a reporter gene that could selectively identify transplanted cells. Nevertheless, these approaches face significant challenges such as providing sufficient signal-to-noise, cellular toxicity, or unequivocal detection. Preclinical studies are currently under way to refine these approaches with initial clinical trials being on the horizon for the next few years. A gradual refinement of these approaches and a robust clinical implementation promise a significant step in ensuring greater efficacy of cell transplants for the diseased liver.
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Fiorina P, Perseghin G, De Cobelli F, Gremizzi C, Petrelli A, Monti L, Maffi P, Luzi L, Secchi A, Del Maschio A. Altered kidney graft high-energy phosphate metabolism in kidney-transplanted end-stage renal disease type 1 diabetic patients: a cross-sectional analysis of the effect of kidney alone and kidney-pancreas transplantation. Diabetes Care 2007; 30:597-603. [PMID: 17327327 DOI: 10.2337/dc06-1324] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Diabetes, hypertension, dyslipidemia, obesity, nephrotoxicity of certain immunosuppressive drugs, and the persistence of a chronic alloimmune response may significantly affect graft survival in end-stage renal disease (ESRD) type 1 diabetic patients who have undergone kidney transplant. The aim of this study was to ascertain the impact of kidney alone (KD) or combined kidney-pancreas (KP) transplantation on renal energy metabolism. RESEARCH DESIGN AND METHODS We assessed high-energy phosphates (HEPs) metabolism by using, in a cross-sectional fashion, 31P-magnetic resonance spectroscopy in the graft of ESRD type 1 diabetic transplanted patients who received KD (n = 20) or KP (n = 20) transplant long before the appearance of overt chronic allograft nephropathy (CAN). Ten nondiabetic microalbuminuric kidney transplanted patients and 10 nondiabetic kidney transplanted patients with overt CAN were chosen as controls subjects. RESULTS Simultaneous KP transplantation patients showed a higher beta-ATP/inorganic phosphorus (Pi) ratio (marker of the graft energy status) versus the other groups, and a positive correlation between beta-ATP/Pi phosphorus ratio and A1C was found. In the analysis limited to the subgroup of normoalbuminuric patients, the difference in beta-ATP/Pi was still detectable in KP patients compared with KD transplantation. CONCLUSIONS KP transplantation was associated with better HEPs than in KD transplantation, suggesting that restoration of beta-cell function positively affects kidney graft metabolism.
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Affiliation(s)
- Paolo Fiorina
- Department of Medicine, San Raffaele Scientific Institute, Via Olgettina 60, Milan 20132, Italy.
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Oldham M, Sakhalkar H, Wang YM, Guo P, Oliver T, Bentley R, Vujaskovic Z, Dewhirst M. Three-dimensional imaging of whole rodent organs using optical computed and emission tomography. JOURNAL OF BIOMEDICAL OPTICS 2007; 12:014009. [PMID: 17343484 DOI: 10.1117/1.2709858] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We explore the potential of optical computed tomography (optical-CT) and optical emission computed tomography (optical-ECT) in a new area-whole organ imaging. The techniques are implemented on an in-house prototype benchtop system with improved image quality and the capacity to image larger samples (up to 3 cm) than previous systems based on stereo microscopes. Imaging performance tests confirm high geometrical accuracy, accurate relative measurement of linear attenuation coefficients, and the ability to image features at the 50-microm level. Optical labeling of organ microvasculature was achieved using two stains deposited via natural in vivo circulatory processes: a passive absorbing ink-based stain and an active fluorescin FITC-lectin conjugate. The lectin protein binds to the endothelial lining, and FITC fluorescense enables optical-ECT imaging. Three-dimensional (3-D) optical-CT images have been acquired of a normal rat heart and left lung and a mouse right lung showing exquisite detail of the functional vasculature and relative perfusion distribution. Coregistered optical-ECT images were also acquired of the mouse lung and kidney. Histological sections confirmed effective labeling of microvasculature throughout the organs. The advantages of optical-CT and optical-ECT include the potential for a unique combination of high resolution and high contrast and compatibility with a wide variety of optical probes, including gene expression labeling fluorescent reporter proteins.
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Affiliation(s)
- Mark Oldham
- Duke University Medical Center, Department of Radiation Oncology and Biomedical Engineering, Durham, North Carolina 27710, USA.
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Beckmann N, Cannet C, Zurbruegg S, Haberthür R, Li J, Pally C, Bruns C. Macrophage Infiltration Detected at MR Imaging in Rat Kidney Allografts: Early Marker of Chronic Rejection? Radiology 2006; 240:717-24. [PMID: 16837667 DOI: 10.1148/radiol.2403050873] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate detection of iron-loaded macrophages at magnetic resonance (MR) imaging as a noninvasive means to monitor early signs of chronic allograft rejection in the life-supporting Fisher-to-Lewis rat kidney transplantation model. MATERIALS AND METHODS Experiments followed the Swiss federal regulations of animal protection. Male Fisher (n = 37) and Lewis (n = 77) rats were used. After removal of a native recipient kidney and transplantation of a donor kidney, the recipient rat's contralateral kidney was removed. Allografts and control syngeneic grafts comprised, respectively, kidneys from Fisher and Lewis donors transplanted into Lewis rats. Recipients were imaged by using a gradient-echo MR sequence 24 hours after intravenous administration of superparamagnetic iron oxide (SPIO) particles. Biochemical analyses of blood and urine, as well as assessments of Banff scores (reference standard for histologic classification of graft rejection), were performed. Statistical tests used were analysis of variance for multiple comparisons with Bonferroni tests, Mann-Whitney tests, and Pearson correlations with Bonferroni corrections. RESULTS A SPIO dose-dependent decrease in cortical MR signal intensity occurred in allografts between 8 and 16 weeks after transplantation. A strong significant negative correlation (P = .005 for 0.3 mL/kg SPIO dose, P = .003 for 1.0 mL/kg SPIO dose) was found between MR signal intensity and Banff scores, which deteriorated over the experimental period. Proteinuria occurred at 16 weeks. Blood and urine creatinine levels remained unchanged up to week 28. CONCLUSION This MR imaging method is more robust than the usually adopted creatinine clearance method for the detection of early signs of allograft chronic rejection in the Fisher-to-Lewis rat kidney transplantation model.
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Affiliation(s)
- Nicolau Beckmann
- Departments of Discovery Technologies and Transplantation Research, Novartis Institutes for BioMedical Research, Lichtstrasse 35, WSJ-386.2.09, CH-4002 Basel, Switzerland.
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Gauvain KM, Garbow JR, Song SK, Hirbe AC, Weilbaecher K. MRI detection of early bone metastases in b16 mouse melanoma models. Clin Exp Metastasis 2006; 22:403-11. [PMID: 16283483 PMCID: PMC2726655 DOI: 10.1007/s10585-005-1264-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Accepted: 07/21/2005] [Indexed: 10/25/2022]
Abstract
Bone metastasis causes significant morbidity in cancer patients, including bone pain, pathologic fractures, nerve compression syndrome, and hypercalcemia. Animal models are utilized to study the pathogenesis of skeletal metastases and to evaluate potential therapeutic agents. Previously published methods for imaging bone metastasis in rodent models have focused on identifying advanced stage metastasis using simple X-rays. Here we report MRI as a method for detecting early bone metastases in mouse models in vivo. B16 mouse melanoma cells were injected into the left cardiac ventricle of C57BL/6 mice and magnetic resonance (MR) images were obtained of the left leg following the development of metastatic disease, when tumor associated bone destruction was histologically present but not visible by X-ray. T1 and T2 relaxation times of bone marrow were measured in healthy control mice and B16 melanoma tumor-bearing mice. Mean T2 values for normal marrow were 28 ms (SD 5) and for diseased bone marrow were 41 ms (SD 3). T2 relaxation time of diseased bone marrow is significantly longer than that of normal bone marrow (P < 0.0001) and can be used as a marker of early bone metastases. These studies demonstrate that MR imaging can detect bone marrow metastases in small animals prior to development of cortical bone loss identified by X-ray.
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Affiliation(s)
- Karen M Gauvain
- Department of Pediatrics, Division of Hematology/Oncology, Washington University School of Medicine, One Children's Place, Box 8116, St. Louis, MO 63110, USA.
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Khan SA, Cox IJ, Hamilton G, Thomas HC, Taylor-Robinson SD. In vivo and in vitro nuclear magnetic resonance spectroscopy as a tool for investigating hepatobiliary disease: a review of H and P MRS applications. Liver Int 2005; 25:273-81. [PMID: 15780050 DOI: 10.1111/j.1478-3231.2005.01090.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a non-invasive technique, which allows the study of cellular biochemistry and metabolism. It is a diverse research tool, widely used by biochemists to investigate pathophysiological processes in vitro and, more recently, by physicians to determine disease abnormalities in vivo. This article reviews the basics of the NMR phenomenon and summarises previous research on the hepatobiliary system using both laboratory-based and clinical methodologies. The role of proton and phosphorus-31 ((31)P) NMR spectroscopy in the study of malignant and non-malignant liver disease and studies of bile composition are discussed. In vivo techniques (magnetic resonance spectroscopy, MRS) can be performed as an adjunct to standard MR examination of the liver. Although still primarily a research tool, the in vivo technique provides non-invasive biochemical information on disease severity and holds promise in its use to gauge response to treatment regimens.
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Affiliation(s)
- Shahid A Khan
- Liver Unit, Department of Medicine A, St Mary's Hospital Campus, Imperial College London, 10th Floor, QEQM Building, London W2 1NY, UK.
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Yoshikawa T, Suzuki Y, Kanashiro M, Li S, Goto T, Tanaka T, Kakinoki K, Sakai T, Tanioka Y, Fujino Y, Kuroda Y. Objective and rapid assessment of pancreas graft viability using 31P-nuclear magnetic resonance spectroscopy combined with two- layer cold storage method. Transplantation 2004; 78:78-82. [PMID: 15257042 DOI: 10.1097/01.tp.0000133516.55002.52] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND With the current shortage of donors, there is a critical need to optimally use "less-than-ideal" donors for pancreas transplantation. Objective and rapid means for assessing graft viability and suitability for transplantation are mandatory. This study examined the possibility of graft viability assessment and posttransplant outcome prediction using (31)P-nuclear magnetic resonance (NMR) spectroscopy combined with the two-layer cold-storage method (TLM). METHODS Canine pancreas grafts were preserved with TLM for 24 hours after 0, 60, or 120 minutes of warm ischemia (groups 1, 2, or 3, respectively). After preservation, we determined intragraft phosphate metabolites noninvasively using (31)P-NMR spectroscopy. Time required for this assessment was 5 minutes. Because our previous studies demonstrated that all grafts in groups 1 and 2 were successfully transplanted (the viable group), whereas all in group 3 failed to survive (the nonviable group), the possibility of posttransplant outcome prediction was examined on the basis of the comparison between these two groups. RESULTS The ratios of inorganic phosphate/gamma-adenosine triphosphate (Pi/gamma-ATP) and Pi/beta-ATP reflected the extent of graft damage, and the differences were statistically significant among groups 1, 2, and 3. On the basis of analyses of receiver operator characteristic curves, the optimum cutoff levels between the viable and nonviable groups were 1.6 and 2.2 for Pi/gammaATP and Pi/betaATP, respectively. The accuracy rates of these ratios were both 83%. CONCLUSION (31)P-NMR spectroscopy combined with TLM preservation could provide an objective, rapid, and possibly noninvasive means to assess pancreas graft viability and to determine suitability of damaged pancreata for organ transplantation.
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Affiliation(s)
- Takuro Yoshikawa
- Division of Gastroenterological Surgery, Department of Clinical Molecular Medicine, Graduate School of Medical Sciences, Kobe University, Kobe, Japan
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Modo M, Roberts TJ, Sandhu JK, Williams SCR. In vivo monitoring of cellular transplants by magnetic resonance imaging and positron emission tomography. Expert Opin Biol Ther 2004; 4:145-55. [PMID: 14998774 DOI: 10.1517/14712598.4.2.145] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Cellular loss is a common pathological observation in many disease conditions. Recent evidence that these cells can be replaced has generated huge excitement over possible clinical applications. The use of stem or progenitor cells, which can differentiate into site-appropriate phenotypes required to "repair" the damaged tissue, has already demonstrated potential in animal models, but many aspects of this novel treatment strategy require further elucidation. Most importantly, the monitoring of the safety of cellular transplants in patients remains a challenge. Traditional histological methods do not address the dynamic nature of transplant-induced recovery and highlight the necessity of in vivo imaging to probe the survival, migration and functional consequences of transplanted cells. This paper reviews how non-invasive imaging technology can be used to serially assess intact living organisms in order to visualise and monitor cellular transplants.
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Affiliation(s)
- Michel Modo
- Neuroimaging Research Group P042, Department of Neurology, Institute of Psychiatry, King's College London, De Crespigny Park, London SE5 8AF, U.K.
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Affiliation(s)
- Pasquina Marzola
- Department of Morphological and Biomedical Sciences, University of Verona, Italy
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Rudin M, Allegrini P, Beckmann N, Gremlich HU, Kneuer R, Laurent D, Rausch M, Stoeckli M. Noninvasive imaging in drug discovery and development. ERNST SCHERING RESEARCH FOUNDATION WORKSHOP 2004:47-75. [PMID: 15248516 DOI: 10.1007/978-3-662-07310-0_3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Affiliation(s)
- M Rudin
- Novartis Institute for Biomedical Research, Analytical and Imaging Sciences Unit, Basel, Switzerland.
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Rudin M, Beckmann N, Rausch M. Magnetic Resonance Imaging in Biomedical Research: Imaging of Drugs and Drug Effects. Methods Enzymol 2004; 385:240-56. [PMID: 15130743 DOI: 10.1016/s0076-6879(04)85014-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Affiliation(s)
- Markus Rudin
- Analytical and Imaging Sciences Unit, Novartis Institute for Biomedical Research, CH-4002 Basel, Switzerland
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Beckmann N, Cannet C, Fringeli-Tanner M, Baumann D, Pally C, Bruns C, Zerwes HG, Andriambeloson E, Bigaud M. Macrophage labeling by SPIO as an early marker of allograft chronic rejection in a rat model of kidney transplantation. Magn Reson Med 2003; 49:459-67. [PMID: 12594748 DOI: 10.1002/mrm.10387] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Anatomical and functional information (renography, perfusion) was obtained by MRI in a life-supporting transplantation model, in which Lewis rats received kidneys from Fisher 344 donors. Renography and perfusion analyses were carried out with Gd-DOTA and small particles of iron oxide (SPIO), respectively. Starting 12 weeks posttransplantation, images from grafts of untreated recipients exhibited distinctive signal attenuation in the cortex. Animals treated with cyclosporin (Sandimmune Neoral; Novartis Pharma, Basel, Switzerland) to prevent acute rejection showed a signal attenuation in the cortex at 33 weeks posttransplantation, while kidneys from rats treated additionally with everolimus (Certican; Novartis), a rapamycin derivative, had no changes in anatomical appearance. A significant negative correlation was found between the MRI cortical signal intensity and the histologically determined iron content in macrophages located in the cortex. Renography revealed a significantly reduced functionality of the kidneys of untreated controls 33 weeks after transplantation, while no significant changes in perfusion were observed in any group of rats. These results suggest the feasibility, by labeling macrophages with SPIO, of detecting signs of graft rejection significantly earlier than when changes in function occur. Monitoring early changes associated with chronic rejection can have an impact in preclinical studies by shortening the duration of the experimental period and by facilitating the investigation of novel immunomodulatory therapies for transplantation.
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Affiliation(s)
- N Beckmann
- Central Technologies, Novartis Institutes for Biomedical Research, CH-4002 Basel, Switzerland.
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Di Felice A, Inguaggiato P, Rubbiani E, Bonucchi D, Savazzi AM, Cerofolini E, Cappelli G, Albertazzi A. Magnetic resonance in renal transplantation: evaluation of post-surgery complications. Transplant Proc 2002; 34:3193-5. [PMID: 12493417 DOI: 10.1016/s0041-1345(02)03620-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- A Di Felice
- Nephrology Dialysis and Renal Transplantation Unit, University Hospital of Modena, Modena, Italy
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Ye Q, Yang D, Williams M, Williams DS, Pluempitiwiriyawej C, Moura JMF, Ho C. In vivo detection of acute rat renal allograft rejection by MRI with USPIO particles. Kidney Int 2002; 61:1124-35. [PMID: 11849467 DOI: 10.1046/j.1523-1755.2002.00195.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Magnetic resonance imaging (MRI) for non-invasively detecting renal rejection was developed by monitoring the accumulation of macrophages labeled with dextran-coated ultrasmall superparamagnetic iron oxide (USPIO) particles at the rat renal allografts during acute rejection. METHODS Five groups of male rats with DA-->BN renal allografts and one group with BN-->BN renal isografts were investigated by MRI before, immediately after, and 24 hr after intravenous infusion with different doses of USPIO particles. All infusions were done on post-operative day 4. MRI experiments were carried out in a 4.7-Tesla instrument using a gradient echo sequence. RESULTS MR signal intensity (MRSI) of the cortex was found to decrease with higher dosages of USPIO particles. In the absence of USPIO infusion, a decrease in MRSI was seen in the medulla region, presumably due to hemorrhage associated with renal graft rejection, while no significant change was observed in the cortex. The optimal dose of USPIO particles for visualizing rejection-associated changes in our rat kidney model appears to be 6 mg Fe/kg body weight. Iron staining results correlated with the MRSI data, indicating that the signal reduction in the MR images was due to the presence of iron. Immunohistochemical results indicated that USPIO particles were mostly taken up by infiltrating macrophages in the rejecting grafts. CONCLUSIONS Our results suggest that MRI with intravenous administration of dextran-coated USPIO particles appears to be a valuable and promising tool that can be used as a non-invasive and sensitive method to detect graft rejection in renal transplantation.
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Affiliation(s)
- Qing Ye
- Department of Biological Sciences, Pittsburgh NMR Center for Biomedical Research, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA 15213-2683, USA
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Papas KK, Colton CK, Gounarides JS, Roos ES, Jarema MA, Shapiro MJ, Cheng LL, Cline GW, Shulman GI, Wu H, Bonner-Weir S, Weir GC. NMR spectroscopy in beta cell engineering and islet transplantation. Ann N Y Acad Sci 2001; 944:96-119. [PMID: 11797699 DOI: 10.1111/j.1749-6632.2001.tb03826.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Islet transplantation is a promising method for restoring normoglycemia and alleviating the long term complications of diabetes. Widespread application of islet transplantation is hindered by the limited supply of human islets and requires a large increase in the availability of suitable insulin secreting tissue as well as robust quality assessment methodologies that can ensure safety and in vivo efficacy. We explore the application of nuclear magnetic resonance (NMR) spectroscopy in two areas relevant to beta cell engineering and islet transplantation: (1) the effect of genetic alterations on glucose metabolism, and (2) quality assessment of islet preparations prior to transplantation. Results obtained utilizing a variety of NMR techniques demonstrate the following: (1) Transfection of Rat1 cells with the c-myc oncogene (which may be involved in cell proliferation and cell cycle regulation) and overexpression of Bcl-2 (which may protect cells from stresses such as hypoxia and exposure to cytokines) introduce a wide array of alterations in cellular biochemistry, including changes in anaerobic and oxidative glucose metabolism, as assessed by 13C and 31P NMR spectroscopy. (2) Overnight incubation of islets and beta cells in the bottom of centrifuge tubes filled with medium at room temperature, as is sometimes done in islet transportation, exposes them to severe oxygen limitations that may cause cell damage. Such exposure, leading to reversible or irreversible damage, can be observed with NMR-detectable markers using conventional 13C and 31P NMR spectroscopy of extracts. In addition, markers of irreversible damage (as well as markers of hypoxia) can be detected and quantified without cell extraction using high-resolution magic angle spinning 1H NMR spectroscopy. Finally, acute ischemia in a bed of perfused beta cells leads to completely reversible changes that can be followed in real time with 31P NMR spectroscopy.
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Affiliation(s)
- K K Papas
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge 02139-4307, USA.
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Beckmann N, Mueggler T, Allegrini PR, Laurent D, Rudin M. From anatomy to the target: contributions of magnetic resonance imaging to preclinical pharmaceutical research. THE ANATOMICAL RECORD 2001; 265:85-100. [PMID: 11323771 DOI: 10.1002/ar.1059] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In recent years, in vivo magnetic resonance (MR) methods have become established tools in the drug discovery and development process. In this article, the role of MR imaging (MRI) in the preclinical evaluation of drugs in animal models of diseases is illustrated on the basis of selected examples. The individual sections are devoted to applications of anatomic, physiologic, and "molecular" imaging providing, respectively, structural-morphological, functional, and target-specific information. The impact of these developments upon clinical drug evaluation is also briefly addressed. The main advantages of MRI are versatility, allowing a comprehensive characterization of a disease state and of the corresponding drug intervention; high spatial resolution; and noninvasiveness, enabling repeated measurements. Successful applications in drug discovery exploit one or several of these aspects. Additionally, MRI is contributing to strengthen the link between preclinical and clinical drug research.
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Affiliation(s)
- N Beckmann
- Novartis Pharma Ltd., Core Technologies Area, Basel, Switzerland.
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Gaschen L, Schuurman HJ, Bruttel K, Tanner M, Beckmann N. MRI and ultrasonographic detection of morphologic and hemodynamic changes in chronic renal allograft rejection in the rat. J Magn Reson Imaging 2001; 13:232-41. [PMID: 11169829 DOI: 10.1002/1522-2586(200102)13:2<232::aid-jmri1034>3.0.co;2-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE The purpose of this study is to describe the sonographic, MRI, and histopathologic findings in a rat model of chronic renal allograft rejection. MATERIALS AND METHODS Allogeneic renal grafts (male DA kidney into male Lewis rat with unilateral nephrectomy, N = 27) and syngeneic renal grafts (male Lewis kidney into male Lewis rat, N = 19) were examined serially with ultrasound, MRI, and histology. RESULTS Nonparametric Spearman rank correlation showed significance between the histologic score and the following parameters: the MRI score (r(s) = 0.91, P < 0.01, N = 46), the ultrasound score (r(s) = 0.9, P < 0.01, N = 46), the power Doppler score (r(s) = 0.86, P < 0.01, N = 46), and the MRI perfusion (r(s) = -0.80, P < 0.01, N = 45). Positive correlations were also found between the MRI volume estimations (graft r(s) = 0.49, P < 0.01, N = 46; native r(s) = 0.59, P < 0.01, N = 46), and the ultrasound volume estimations (graft r(s) = 0.39, P < 0.01, N = 45; native r(s) = 0.64, P < 0.01, N = 46) as well as with actual graft weight. CONCLUSIONS This study shows that both MRI and ultrasound can provide complementary, accurate information compared to histology in regard to the alterations in anatomy and hemodynamic changes associated with chronic allograft nephropathy.
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Affiliation(s)
- L Gaschen
- Transplantation Research, Novartis Pharma Inc., Kohlenstrasse 35, WSJ-386.526, CH-4002 Basel, Switzerland.
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