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Ahlström, Håkan
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Publications (10 of 185) Show all publications
Carlbom, L., Espes, D., Lubberink, M., Martinell, M., Johansson, L., Ahlström, H., . . . Eriksson, O. (2017). [(11)C]5-Hydroxy-Tryptophan PET for Assessment of Islet Mass During Progression of Type 2 Diabetes. Diabetes, 66(5), 1286-1292.
Open this publication in new window or tab >>[(11)C]5-Hydroxy-Tryptophan PET for Assessment of Islet Mass During Progression of Type 2 Diabetes
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2017 (English)In: Diabetes, ISSN 0012-1797, E-ISSN 1939-327X, Vol. 66, no 5, 1286-1292 p.Article in journal (Refereed) Published
Abstract [en]

[(11)C]5-hydroxy-tryptophan ([(11)C]5-HTP) PET of the pancreas has been shown to be a surrogate imaging biomarker of pancreatic islet mass. The change in islet mass in different stages of type 2 diabetes (T2D) as measured by non-invasive imaging is currently unknown. Here, we describe a cross-sectional study where subjects at different stages of T2D development with expected stratification of pancreatic islet mass were examined in relation to non-diabetic individuals. The primary outcome was the [(11)C]5-HTP uptake and retention in pancreas, as a surrogate marker for the endogenous islet mass.We found that metabolic testing indicated a progressive loss of beta cell function, but that this was not mirrored by a decrease in [(11)C]5-HTP tracer accumulation in the pancreas. This provides evidence of retained islet mass despite decreased beta cell function. The results herein indicates that beta cell dedifferentiation, and not necessarily endocrine cell loss, constitute a major cause of beta cell failure in T2D.

National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:uu:diva-316831 (URN)10.2337/db16-1449 (DOI)000399799800022 ()28246291 (PubMedID)
Funder
Swedish Society for Medical Research (SSMF), K2015-54X-12219-19-4 K2013-64X-08268-26-3 K2013-55X-15043 921-2014-7054Novo NordiskSwedish Child Diabetes Foundation
Note

De 2 första författarna delar förstaförfattarskapet.

Available from: 2017-03-07 Created: 2017-03-07 Last updated: 2017-05-11Bibliographically approved
Strand, R., Malmberg, F., Johansson, L., Lind, L., Sundbom, M., Ahlström, H. & Kullberg, J. (2017). A concept for holistic whole body MRI data analysis, Imiomics. PLoS ONE, 12(2), Article ID e0169966.
Open this publication in new window or tab >>A concept for holistic whole body MRI data analysis, Imiomics
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2017 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 2, e0169966Article in journal (Refereed) Published
Abstract [en]

Purpose: To present and evaluate a whole-body image analysis concept, Imiomics (imaging omics) and an image registration method that enables Imiomics analyses by deforming all image data to a common coordinate system, so that the information in each voxel can be compared between persons or within a person over time and integrated with non-imaging data.

Methods: The presented image registration method utilizes relative elasticity constraints of different tissue obtained from whole-body water-fat MRI. The registration method is evaluated by inverse consistency and Dice coefficients and the Imiomics concept is evaluated by example analyses of importance for metabolic research using non-imaging parameters where we know what to expect. The example analyses include whole body imaging atlas creation, anomaly detection, and cross-sectional and longitudinal analysis.

Results: The image registration method evaluation on 128 subjects shows low inverse consistency errors and high Dice coefficients. Also, the statistical atlas with fat content intensity values shows low standard deviation values, indicating successful deformations to the common coordinate system. The example analyses show expected associations and correlations which agree with explicit measurements, and thereby illustrate the usefulness of the proposed Imiomics concept.

Conclusions: The registration method is well-suited for Imiomics analyses, which enable analyses of relationships to non-imaging data, e.g. clinical data, in new types of holistic targeted and untargeted big-data analysis.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Research subject
Computerized Image Processing
Identifiers
urn:nbn:se:uu:diva-316830 (URN)10.1371/journal.pone.0169966 (DOI)000395934400002 ()28241015 (PubMedID)
Available from: 2017-02-27 Created: 2017-03-07 Last updated: 2017-11-29Bibliographically approved
Straniero, S., Rosqvist, F., Edholm, D., Ahlström, H., Kullberg, J., Sundbom, M., . . . Rudling, M. (2017). Acute caloric restriction counteracts hepatic bile acid and cholesterol deficiency in morbid obesity. Journal of Internal Medicine, 281(5), 507-517.
Open this publication in new window or tab >>Acute caloric restriction counteracts hepatic bile acid and cholesterol deficiency in morbid obesity
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2017 (English)In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 281, no 5, 507-517 p.Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Bile acid (BA) synthesis is regulated by BA signalling in the liver and by fibroblast growth factor 19 (FGF19), synthesized and released from the intestine. In morbid obesity, faecal excretion and hepatic synthesis of BAs and cholesterol are strongly induced and caloric restriction reduces their faecal excretion considerably. We hypothesized that the high intestinal food mass in morbidly obese subjects promotes faecal excretion of BAs and cholesterol, thereby creating a shortage of both BAs and cholesterol in the liver.

METHODS: Ten morbidly obese women (BMI 42 ± 2.6 kg m(-2) ) were monitored on days 0, 3, 7, 14 and 28 after beginning a low-calorie diet (800-1100 kcal day(-1) ). Serum was collected and liver size and fat content determined. Synthesis of BAs and cholesterol was evaluated from serum markers, and the serum levels of lipoproteins, BAs, proprotein convertase subtilisin/kexin type 9 (PCSK9), insulin, glucose and FGF19 were monitored. Fifty-four nonobese women (BMI <25 kg m(-2) ) served as controls.

RESULTS: At baseline, synthesis of both BAs and cholesterol and serum levels of BAs and PCSK9 were elevated in the obese group compared to controls. Already after 3 days on a low-calorie diet, BA and cholesterol synthesis and serum BA and PCSK9 levels normalized, whereas LDL cholesterol increased. FGF19 and triglyceride levels were unchanged, and liver volume was reduced by 10%.

CONCLUSIONS: The results suggest that hepatic BAs and cholesterol are deficient in morbid obesity. Caloric restriction rapidly counteracts these deficiencies, normalizing BA and cholesterol synthesis and circulating PCSK9 levels, indicating that overproduction of cholesterol in enlarged peripheral tissues cannot explain this phenotype. We propose that excessive food intake promotes faecal loss of BAs and cholesterol contributing to their hepatic deficiencies.

Keyword
bile acid synthesis, cholesterol synthesis, proprotein convertase subtilisin/kexin type 9
National Category
Nutrition and Dietetics
Identifiers
urn:nbn:se:uu:diva-316832 (URN)10.1111/joim.12599 (DOI)000399779700009 ()28261926 (PubMedID)
Funder
Swedish Research Council, 2015-02781Swedish Heart Lung Foundation, 20160491Stockholm County Council, ALF 20150447Swedish Diabetes Association
Available from: 2017-03-07 Created: 2017-03-07 Last updated: 2017-05-29Bibliographically approved
von Below, C., Wassberg, C., Norberg, M., Tolf, A., Kullberg, J., Ladjevardi, S., . . . Ahlström, H. (2017). Additional value of magnetic resonance-targeted biopsies to standard transrectal ultrasound-guided biopsies for detection of clinically significant prostate cancer. Scandinavian journal of urology, 51(2), 107-113.
Open this publication in new window or tab >>Additional value of magnetic resonance-targeted biopsies to standard transrectal ultrasound-guided biopsies for detection of clinically significant prostate cancer
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2017 (English)In: Scandinavian journal of urology, ISSN 2168-1805, E-ISSN 2168-1813, Vol. 51, no 2, 107-113 p.Article in journal (Refereed) Published
Abstract [en]

OBJECTIVE: The aim of this study was to evaluate the additional value of magnetic resonance imaging-targeted biopsy (MRI-TB) to standard transrectal ultrasound-guided biopsy (SB) for detection of clinically significant prostate cancer (PCa). An additional aim was to compare the biopsy results to MRI evaluation using a Likert scale.

MATERIALS AND METHODS: Patients with newly diagnosed localized PCa (n = 53) by clinical routine SB were prospectively included. The majority of the patients were scheduled for curative therapy before enrollment. The patients underwent multiparametric MRI (mpMRI) at 3 T using an endorectal coil followed by two MRI-TBs, using ultrasound with cognitive fusion. All included patients underwent MRI-TB, even those who had low to very low suspicion of significant PCa on mpMRI. The detection rate of significant cancer on SB versus SB + MRI-TB was compared in the 53 included patients and with whole-mounted histopathology as reference in 34 cases. Comparison of the biopsy results to MRI evaluation and interreader agreement calculation of five-point Likert score evaluation were performed.

RESULTS: In total, 32 significant (Gleason ≥7) PCa were detected by SB, while SB + MRI-TB detected an additional five significant PCa. MRI-TB alone detected 20 and missed 17 significant PCa. Ten of the significant PCa cases missed by MRI-TB had a Likert score of 3 or lower. Interreader agreement using the Likert scale was high, with a kappa value of 0.77 (95% confidence interval 0.63-0.92, p < 0.0001).

CONCLUSION: Detection of significant PCa increased by adding MRI-TB to SB. This may not be of enough clinical value to justify the use of targeted biopsies in this patient group.

Keyword
Magnetic resonance imaging, prostatic neoplasm, targeted biopsies, transrectal ultrasound-guided biopsy
National Category
Urology and Nephrology Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-325563 (URN)10.1080/21681805.2017.1281346 (DOI)000403629400003 ()28635568 (PubMedID)
Funder
Swedish Cancer Society
Available from: 2017-06-26 Created: 2017-06-26 Last updated: 2017-10-19Bibliographically approved
Kullberg, J., Hedström, A., Brandberg, J., Strand, R., Johansson, L. E., Bergström, G. & Ahlström, H. (2017). Automated analysis of liver fat, muscle and adipose tissue distribution from CT suitable for large-scale studies.. Scientific Reports, 7, Article ID 10425.
Open this publication in new window or tab >>Automated analysis of liver fat, muscle and adipose tissue distribution from CT suitable for large-scale studies.
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2017 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 10425Article in journal (Refereed) Published
Abstract [en]

Computed Tomography (CT) allows detailed studies of body composition and its association with metabolic and cardiovascular disease. The purpose of this work was to develop and validate automated and manual image processing techniques for detailed and efficient analysis of body composition from CT data. The study comprised 107 subjects examined in the Swedish CArdioPulmonary BioImage Study (SCAPIS) using a 3-slice CT protocol covering liver, abdomen, and thighs. Algorithms were developed for automated assessment of liver attenuation, visceral (VAT) and subcutaneous (SAT) abdominal adipose tissue, thigh muscles, subcutaneous, subfascial (SFAT) and intermuscular adipose tissue. These were validated using manual reference measurements. SFAT was studied in selected subjects were the fascia lata could be visually identified (approx. 5%). In addition, precision of manual measurements of intra- (IPAT) and retroperitoneal adipose tissue (RPAT) and deep- and superficial SAT was evaluated using repeated measurements. Automated measurements correlated strongly to manual reference measurements. The SFAT depot showed the weakest correlation (r = 0.744). Automated VAT and SAT measurements were slightly, but significantly overestimated (≤4.6%, p ≤ 0.001). Manual segmentation of abdominal sub-depots showed high repeatability (CV ≤ 8.1%, r ≥ 0.930). We conclude that the low dose CT-scanning and automated analysis makes the setup suitable for large-scale studies.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-329273 (URN)10.1038/s41598-017-08925-8 (DOI)000409309300013 ()28874743 (PubMedID)
Funder
Swedish Research Council, 2012-2330Swedish Heart Lung FoundationVINNOVA
Available from: 2017-09-11 Created: 2017-09-11 Last updated: 2017-12-06Bibliographically approved
Lundström, E., Strand, R., Forslund, A., Bergsten, P., Weghuber, D., Ahlström, H. & Kullberg, J. (2017). Automated segmentation of human cervical-supraclavicular adipose tissue in magnetic resonance images. Scientific Reports, 7, Article ID 3064.
Open this publication in new window or tab >>Automated segmentation of human cervical-supraclavicular adipose tissue in magnetic resonance images
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2017 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, 3064Article in journal (Refereed) Published
Abstract [en]

Human brown adipose tissue (BAT), with a major site in the cervical-supraclavicular depot, is a promising anti-obesity target. This work presents an automated method for segmenting cervical-supraclavicular adipose tissue for enabling time-efficient and objective measurements in large cohort research studies of BAT. Fat fraction (FF) and R2* maps were reconstructed from water-fat magnetic resonance imaging (MRI) of 25 subjects. A multi-atlas approach, based on atlases from nine subjects, was chosen as automated segmentation strategy. A semi-automated reference method was used to validate the automated method in the remaining subjects. Automated segmentations were obtained from a pipeline of preprocessing, affine registration, elastic registration and postprocessing. The automated method was validated with respect to segmentation overlap (Dice similarity coefficient, Dice) and estimations of FF, R2* and segmented volume. Bias in measurement results was also evaluated. Segmentation overlaps of Dice = 0.93 +/- 0.03 (mean +/- standard deviation) and correlation coefficients of r > 0.99 (P < 0.0001) in FF, R2* and volume estimates, between the methods, were observed. Dice and BMI were positively correlated (r = 0.54, P = 0.03) but no other significant bias was obtained (P >= 0.07). The automated method compared well with the reference method and can therefore be suitable for time-efficient and objective measurements in large cohort research studies of BAT.

National Category
Radiology, Nuclear Medicine and Medical Imaging
Research subject
Computerized Image Processing
Identifiers
urn:nbn:se:uu:diva-323968 (URN)10.1038/s41598-017-01586-7 (DOI)000402865000003 ()28596551 (PubMedID)
Funder
Swedish Research CouncilEU, FP7, Seventh Framework Programme, 279153
Available from: 2017-06-08 Created: 2017-06-12 Last updated: 2017-09-19Bibliographically approved
Lind, L., Nylander, R., Johansson, L., Kullberg, J., Ahlström, H. & Larsson, E.-M. (2017). Endothelium-dependent vasodilation is related to the occurrence of cortical brain infarcts at MR imaging: The Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Clinical Physiology and Functional Imaging, 37(2), 194-197.
Open this publication in new window or tab >>Endothelium-dependent vasodilation is related to the occurrence of cortical brain infarcts at MR imaging: The Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study
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2017 (English)In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 37, no 2, 194-197 p.Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Infarcts in the brain can be divided into larger cortical and smaller deep lacunar infarcts. The pathogenesis differs between these two types of infarctions.

OBJECTIVE: This study aims to investigate the relationship between measures of endothelium-dependent vasodilation (EDV) and occurrence of cortical and lacunar infarcts in a population-based sample.

METHODS: In the Prospective Study of the Vasculature in Uppsala Seniors (PIVUS) study, 1016 subjects aged 70 were evaluated by the invasive forearm technique with acetylcholine (EDV) and brachial artery ultrasound to assess flow-mediated vasodilation (FMD). Six to seven years later MRI of the brain was performed, and the prevalence of cortical and lacunar infarcts was visually assessed in 407 randomly selected subjects.

RESULTS: Lacunar infarcts were found in 22% and cortical infarcts in 5·9% of the subjects. EDV and FMD were both significantly related to the occurrence of cortical, but not lacunar infarcts. In a model adjusting for gender, waist circumference, body mass index, fasting blood glucose, systolic and diastolic blood pressure, HDL and LDL cholesterol, serum triglycerides, smoking, antihypertensive treatment and statin use, both EDV and FMD were independent predictors of cortical infarcts (P = 0·035 and P = 0·008, respectively).

CONCLUSIONS: Endothelium-dependent vasodilation in both forearm resistance vessels and the brachial artery was related to the occurrence of cortical, but not lacunar, infarcts at MRI in a population-based sample independently of traditional risk factors.

National Category
Cardiac and Cardiovascular Systems Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-261198 (URN)10.1111/cpf.12285 (DOI)000395108400014 ()26303051 (PubMedID)
Available from: 2015-08-31 Created: 2015-08-31 Last updated: 2017-04-25Bibliographically approved
Rosqvist, F., Bjermo, H., Kullberg, J., Johansson, L., Michaëlsson, K., Ahlström, H., . . . Risérus, U. (2017). Fatty acid composition in serum cholesterol esters and phospholipids is linked to visceral and subcutaneous adipose tissue content in elderly individuals: a cross-sectional study. Lipids in Health and Disease, 16, 1-10, Article ID 68.
Open this publication in new window or tab >>Fatty acid composition in serum cholesterol esters and phospholipids is linked to visceral and subcutaneous adipose tissue content in elderly individuals: a cross-sectional study
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2017 (English)In: Lipids in Health and Disease, ISSN 1476-511X, E-ISSN 1476-511X, Vol. 16, 1-10 p., 68Article in journal (Refereed) Published
Abstract [en]

Background: Visceral adipose tissue (VAT) and truncal fat predict cardiometabolic disease. Intervention trials suggest that saturated fatty acids (SFA), e. g. palmitic acid, promote abdominal and liver fat storage whereas polyunsaturated fatty acids (PUFA), e. g. linoleic acid, prevent fat accumulation. Such findings require investigation in population-based studies of older individuals. We aimed to investigate the relationships of serum biomarkers of PUFA intake as well as serum levels of palmitic acid, with abdominal and total adipose tissue content.

Methods: In a population-based sample of 287 elderly subjects in the PIVUS cohort, we assessed fatty acid composition in serum cholesterol esters (CE) and phospholipids (PL) by gas chromatography and the amount of VAT and abdominal subcutaneous (SAT) adipose tissue by magnetic resonance imaging (MRI), liver fat by MR spectroscopy (MRS), and total body fat, trunk fat and leg fat by dual-energy X-ray absorptiometry (DXA). Insulin resistance was estimated by HOMA-IR.

Results: VAT and trunk fat showed the strongest correlation with insulin resistance (r = 0.49, P < 0.001). Linoleic acid in both CE and PL was inversely related to all body fat depots (r = -0.24 to -0.33, P < 0.001) including liver fat measured in a sub-group (r = -0.26, P < 0.05, n = 73), whereas n-3 PUFA showed weak inverse (18: 3n-3) or positive (20: 5n-3) associations. Palmitic acid in CE, but not in PL, was directly correlated with VAT (r = 0.19, P < 0.001) and trunk fat (r = 0.18, P = 0.003). Overall, the significant associations remained after adjusting for energy intake, height, alcohol, sex, smoking, education and physical activity. The inverse correlation between linoleic acid and VAT remained significant after further adjustment for total body fat.

Conclusions: Serum linoleic acid is inversely related to body fat storage including VAT and trunk fat whereas palmitic acid was less consistently but directly associated, in line with recent feeding studies. Considering the close link between VAT and insulin resistance, a potential preventive role of plant-based PUFA in VAT accumulation warrants further study.

Keyword
Adipose tissue distribution, Body fat, Fatty acid, Linoleic acid, Palmitic acid, Polyunsaturated fat, Saturated fat, Visceral adipose tissue
National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:uu:diva-319605 (URN)10.1186/s12944-017-0445-2 (DOI)000398222200001 ()28372558 (PubMedID)
Funder
Swedish Research Council, K2015-54X-22081-04-3EXODIAB - Excellence of Diabetes Research in SwedenSwedish Diabetes Association
Available from: 2017-04-06 Created: 2017-04-06 Last updated: 2017-11-29Bibliographically approved
Staaf, J., Labmayr, V., Paulmichl, K., Manell, H., Cen, J., Ciba, I., . . . Kullberg, J. (2017). Pancreatic Fat Is Associated With Metabolic Syndrome and Visceral Fat but Not Beta-Cell Function or Body Mass Index in Pediatric Obesity. Pancreas, 46(3), 358-365.
Open this publication in new window or tab >>Pancreatic Fat Is Associated With Metabolic Syndrome and Visceral Fat but Not Beta-Cell Function or Body Mass Index in Pediatric Obesity
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2017 (English)In: Pancreas, ISSN 0885-3177, E-ISSN 1536-4828, Vol. 46, no 3, 358-365 p.Article in journal (Refereed) Published
Abstract [en]

OBJECTIVE: Adolescents with obesity have increased risk of type 2 diabetes and metabolic syndrome (MetS). Pancreatic fat has been related to these conditions; however, little is known about associations in pediatric obesity. The present study was designed to explore these associations further.

METHODS: We examined 116 subjects, 90 with obesity. Anthropometry, MetS, blood samples, and oral glucose tolerance tests were assessed using standard techniques. Pancreatic fat fraction (PFF) and other fat depots were quantified using magnetic resonance imaging.

RESULTS: The PFF was elevated in subjects with obesity. No association between PFF and body mass index-standard deviation score (BMI-SDS) was found in the obesity subcohort. Pancreatic fat fraction correlated to Insulin Secretion Sensitivity Index-2 and Homeostatic Model Assessment of Insulin Resistance in simple regression; however, when using adjusted regression and correcting for BMI-SDS and other fat compartments, PFF correlated only to visceral adipose tissue and fasting glucose. Highest levels of PFF were found in subjects with obesity and MetS.

CONCLUSIONS: In adolescents with obesity, PFF is elevated and associatedto MetS, fasting glucose, and visceral adipose tissue but not to beta-cellfunction, glucose tolerance, or BMI-SDS. This study demonstrates thatconclusions regarding PFF and its associations depend on the body massfeatures of the cohort.

Keyword
pancreatic fat, pediatric obesity, beta-cell function, metabolic syndrome, body mass index-standard deviation score
National Category
Endocrinology and Diabetes
Identifiers
urn:nbn:se:uu:diva-311308 (URN)10.1097/MPA.0000000000000771 (DOI)000394448600018 ()27941426 (PubMedID)
Funder
Swedish Research Council, 72X-14019 2012-2330 2011-4423Swedish Diabetes AssociationEU, FP7, Seventh Framework Programme, 279153
Note

De två första författarna delar förstaförfattarskapet.

Available from: 2016-12-22 Created: 2016-12-22 Last updated: 2017-04-26Bibliographically approved
Carlbom, L., Weis, J., Johansson, L., Korsgren, O. & Ahlström, H. (2017). Pre-transplantation ³¹P-magnetic resonance spectroscopy for quality assessment of human pancreatic grafts: A feasibility study. Magnetic Resonance Imaging, 39, 98-102.
Open this publication in new window or tab >>Pre-transplantation ³¹P-magnetic resonance spectroscopy for quality assessment of human pancreatic grafts: A feasibility study
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2017 (English)In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 39, 98-102 p.Article in journal (Refereed) Published
Abstract [en]

Objective: To investigate the feasibility of using (31)P-MRS for objective non-invasive quality assessment of human pancreas grafts prior to transplantation or islet isolation.

Materials and methods: Pancreata from 5 human donors, 3 males and 2 females, aged 49-78years, with body mass index (BMI) 22-31kg/m(2), were included. Pancreata were perfused with histidine-tryptophan-ketoglutarate solution during procurement and stored in hypothermic condition (4°C) for 21-44h. During the period of hypothermic storage repeated spectra were obtained for each graft by (31)P-MRS (1.5Tesla) to measure the cold ischemia time (CIT) dependent changes of the phosphorous metabolites adenosine triphosphate (ATP), phosphomonoesters (PME), phosphodiesters (PDE) and inorganic phosphate (Pi), in the grafts. Graft temperature was measured immediately before and after MR-examination. Reference spectrum for non-viable tissue was obtained after graft exposure to room temperature.

Results: PME/Pi, PDE/Pi and ATP/Pi spectral intensities ratios decreased with increasing CIT, reflecting the decreased viability of the grafts. PME/Pi ratio was the most discriminatory variable at prolonged CIT. (31)P-MRS could be performed without significantly increasing graft temperature.

Conclusions: (31)P-MRS may provide quantitative parameters for evaluating graft viability ex vivo, and is a promising tool for objective non-invasive assessment of the quality of human pancreas grafts prior to transplantation or islet isolation.

Keyword
P-31-MR spectroscopy, Organ viability, Pancreas transplantation, Cold ischemia, ATP, PME
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
urn:nbn:se:uu:diva-315894 (URN)10.1016/j.mri.2017.02.004 (DOI)000401051200012 ()28188872 (PubMedID)
Funder
Swedish Research Council, K2013-64X-08268-26-3Swedish Research Council, 921-2014-7054Swedish Research Council, K2015-54X-12219-19-4Swedish Child Diabetes FoundationSwedish Diabetes AssociationEXODIAB - Excellence of Diabetes Research in Sweden
Note

Title in WOS: Pre-transplantation P-31-magnetic resonance spectroscopy for quality assessment of human pancreatic grafts - A feasibility study

Available from: 2017-02-22 Created: 2017-02-22 Last updated: 2017-06-20Bibliographically approved
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