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Jones A, Bray TJP, Sakai NS, Bainbridge AJP, Ciurtin C, Hall-Craggs MA. Measuring response to treatment in axial spondyloarthritis using quantitative imaging biomarkers: a prospective observational cohort study. Br J Radiol 2023; 96:20220530. [PMID: 37751217 PMCID: PMC10646635 DOI: 10.1259/bjr.20220530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/13/2023] [Accepted: 09/19/2023] [Indexed: 09/27/2023] Open
Abstract
OBJECTIVE Objective assessments of disease activity and response to treatment in axial spondyloarthritis (axSpA) remain a challenge; quantitative imaging biomarkers (QIBs) of inflammation could enhance assessments of disease activity and therapeutic response. We aimed to determine the responsiveness of QIBs obtained from diffusion-weighted imaging (DW-MRI) and chemical shift-encoded MRI (CSE-MRI) using the partially automated Bone Edema and Adiposity Characterisation with Histograms (BEACH) software tool in axSpA patients undergoing biologic therapy. METHODS We conducted a prospective longitudinal cohort study, including 30 patients with axSpA undergoing biologic therapy. Patients were scanned before and after biologic therapy using conventional MRI, DWI and CSE-MRI at 3T. Apparent diffusion coefficient (ADC) and proton density fat fraction (PDFF) were assessed using the BEACH tool (https://github.com/TJPBray/BEACH), and conventional MR images were assessed using established visual scoring methods by expert radiologists. Responsiveness - the ability of the MRI measurements to capture changes in disease occurring as a result of biologic therapy - was assessed using the standardized response mean (SRM). Inter-reader reliability of the ADC and PDFF maps was assessed using Bland-Altman limits of agreement analysis and the intraclass correlation coefficient. RESULTS Responsiveness to therapy was moderate for ADC-based parameters (SRM 0.50) and comparable to established visual scoring methods for bone marrow oedema (SRM 0.53). Interobserver variability was lower for QIBs compared with conventional visual scores methods. CONCLUSIONS QIBs measured using the BEACH tool are sensitive to changes in inflammation in axSpA following biologic therapy, with similar responsiveness and lower interobserver variability to visual scoring by expert radiologists. ADVANCES IN KNOWLEDGE QIBs measured using the partially automated BEACH tool offer an objective measure of response to biologic therapy in axSpA.
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Affiliation(s)
- Alexis Jones
- Department of Rheumatology, University College London Hospitals NHS Foundation Trust, London, UK
| | - Timothy JP Bray
- Centre for Medical Imaging, University College London, London, UK
| | - Naomi S Sakai
- Centre for Medical Imaging, University College London, London, UK
| | - Alan JP Bainbridge
- Department of Medical Physics and Biomedical Engineering, University College London Hospital, London, UK
| | - Coziana Ciurtin
- Department of Rheumatology, University College London Hospitals NHS Foundation Trust, London, UK
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Chaiyasoot K, Sakai NS, Zakeri R, Makaronidis J, Crisóstomo L, Alves MG, Gan W, Firman C, Jassil FC, Hall-Craggs MA, Taylor SA, Batterham RL. Weight-loss Independent Clinical and Metabolic Biomarkers Associated with Type 2 Diabetes Remission Post-bariatric/metabolic Surgery. Obes Surg 2023; 33:3988-3998. [PMID: 37910328 PMCID: PMC10687127 DOI: 10.1007/s11695-023-06905-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 10/04/2023] [Accepted: 10/11/2023] [Indexed: 11/03/2023]
Abstract
PURPOSE Remission of type 2 diabetes (T2D) can be achieved by many, but not all, people following bariatric/metabolic surgery. The mechanisms underlying T2D remission remain incompletely understood. This observational study aimed to identify novel weight-loss independent clinical, metabolic and genetic factors that associate with T2D remission using comprehensive phenotyping. MATERIALS AND METHODS Ten patients without T2D remission (non-remitters) were matched to 10 patients with T2D remission (remitters) for age, sex, type of surgery, body weight, BMI, post-operative weight loss, duration from surgery and duration of T2D. Detailed body composition assessed using magnetic resonance imaging, gut hormones, serum metabolomics, insulin sensitivity, and genetic risk scores for T2D and anthropometric traits were assessed. RESULTS Remitters had significantly greater β-cell function and circulating acyl ghrelin levels, but lower visceral adipose tissue (VAT): subcutaneous adipose tissue (SAT) ratio than non-remitters. Branched-chain amino acids (BCAAs) and VLDL particle size were the most discriminant metabolites between groups. A significant positive correlation between, VAT area, VAT:SAT ratio and circulating levels of BCAAs was observed, whereas a significant negative correlation between BCAAs and β-cell function was revealed. CONCLUSION We highlight a potentially novel relationship between VAT and BCAAs, which may play a role in glucoregulatory control. Improvement in β-cell function, and the role ghrelin plays in its recovery, is likely another key factor influencing T2D remission post-surgery. These findings suggest that adjunctive approaches that target VAT loss and restoration of BCAA metabolism might achieve higher rates of long-term T2D remission post-surgery.
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Affiliation(s)
- Kusuma Chaiyasoot
- Department of Medicine, Centre for Obesity Research, University College London, London, UK
- Division of Nutrition, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
- The Siriraj Center of Research Excellence for Diabetes and Obesity (SiCORE-DO), Mahidol University, Bangkok, Thailand
| | | | - Roxanna Zakeri
- Department of Medicine, Centre for Obesity Research, University College London, London, UK
| | - Janine Makaronidis
- Department of Medicine, Centre for Obesity Research, University College London, London, UK
- National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London, UK
| | - Luís Crisóstomo
- Department of Immunophysiology and Pharmacology, ICBAS - School of Medicine and Biomedical Sciences, UMIB - Unit for Multidisciplinary Research in Biomedicine, University of Porto, Porto, Portugal
- ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal
- Institute of Biomedicine, University of Turku, Turku, Finland
| | - Marco G Alves
- Department of Immunophysiology and Pharmacology, ICBAS - School of Medicine and Biomedical Sciences, UMIB - Unit for Multidisciplinary Research in Biomedicine, University of Porto, Porto, Portugal
- ITR - Laboratory for Integrative and Translational Research in Population Health, Porto, Portugal
| | - Wei Gan
- Genetics Department, Novo Nordisk Research Centre Oxford, Innovation Building, Old Road Campus, Headington, OX37LQ, UK
| | - Chloe Firman
- Department of Medicine, Centre for Obesity Research, University College London, London, UK
| | - Friedrich C Jassil
- Department of Medicine, Centre for Obesity Research, University College London, London, UK
| | - Margaret A Hall-Craggs
- UCL Centre for Medical Imaging, London, UK
- National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London, UK
| | - Stuart A Taylor
- UCL Centre for Medical Imaging, London, UK
- National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London, UK
| | - Rachel L Batterham
- Department of Medicine, Centre for Obesity Research, University College London, London, UK.
- National Institute of Health Research, University College London Hospitals Biomedical Research Centre, London, UK.
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Mingrone G, van Baar AC, Devière J, Hopkins D, Moura E, Cercato C, Rajagopalan H, Lopez-Talavera JC, White K, Bhambhani V, Costamagna G, Haidry R, Grecco E, Galvao Neto M, Aithal G, Repici A, Hayee B, Haji A, Morris AJ, Bisschops R, Chouhan MD, Sakai NS, Bhatt DL, Sanyal AJ, Bergman JJGHM. Safety and efficacy of hydrothermal duodenal mucosal resurfacing in patients with type 2 diabetes: the randomised, double-blind, sham-controlled, multicentre REVITA-2 feasibility trial. Gut 2022; 71:254-264. [PMID: 33597157 PMCID: PMC8761999 DOI: 10.1136/gutjnl-2020-323608] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/26/2020] [Accepted: 01/30/2021] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Hydrothermal duodenal mucosal resurfacing (DMR) is a safe, outpatient endoscopic procedure. REVITA-2, a double-blind, superiority randomised controlled trial, investigates safety and efficacy of DMR using the single catheter Revita system (Revita DMR (catheter and system)), on glycaemic control and liver fat content in type 2 diabetes (T2D). DESIGN Eligible patients (haemoglobin A1c (HbA1c) 59-86 mmol/mol, body mass index≥24 and ≤40 kg/m2, fasting insulin >48.6 pmol/L, ≥1 oral antidiabetic medication) enrolled in Europe and Brazil. Primary endpoints were safety, change from baseline in HbA1c at 24 weeks, and liver MRI proton-density fat fraction (MRI-PDFF) at 12 weeks. RESULTS Overall mITT (DMR n=56; sham n=52), 24 weeks post DMR, median (IQR) HbA1c change was -10.4 (18.6) mmol/mol in DMR group versus -7.1 (16.4) mmol/mol in sham group (p=0.147). In patients with baseline liver MRI-PDFF >5% (DMR n=48; sham n=43), 12-week post-DMR liver-fat change was -5.4 (5.6)% in DMR group versus -2.9 (6.2)% in sham group (p=0.096). Results from prespecified interaction testing and clinical parameter assessment showed heterogeneity between European (DMR n=39; sham n=37) and Brazilian (DMR n=17; sham n=16) populations (p=0.063); therefore, results were stratified by region. In European mITT, 24 weeks post DMR, median (IQR) HbA1c change was -6.6 mmol/mol (17.5 mmol/mol) versus -3.3 mmol/mol (10.9 mmol/mol) post-sham (p=0.033); 12-week post-DMR liver-fat change was -5.4% (6.1%) versus -2.2% (4.3%) post-sham (p=0.035). Brazilian mITT results trended towards DMR benefit in HbA1c, but not liver fat, in context of a large sham effect. In overall PP, patients with high baseline fasting plasma glucose ((FPG)≥10 mmol/L) had significantly greater reductions in HbA1c post-DMR versus sham (p=0.002). Most adverse events were mild and transient. CONCLUSIONS DMR is safe and exerts beneficial disease-modifying metabolic effects in T2D with or without non-alcoholic liver disease, particularly in patients with high FPG. TRIAL REGISTRATION NUMBER NCT02879383.
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Affiliation(s)
- Geltrude Mingrone
- Division of Obesity and Metabolic Diseases, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Rome, Italy
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK
| | - Annieke Cg van Baar
- Departments of Gastroenterology and Hepatology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands
| | - Jacques Devière
- Department of Gastroenterology, Erasme University Hospital, Brussels, Belgium
| | - David Hopkins
- Institute of Diabetes, Endocrinology and Obesity, King's Health Partners, London, UK
| | - Eduardo Moura
- Department of Gastroenterology, Universidade de Sao Paulo Medical School, Sao Paulo, Brazil
| | - Cintia Cercato
- Obesity Unit, Department of Endocrinology, Hospital das Clínicas, University of Sao Paulo, Sao Paulo, Brazil
| | - Harith Rajagopalan
- Research and Development, Fractyl Laboratories, Inc, Lexington, Massachusetts, USA
| | | | - Kelly White
- Research and Development, Fractyl Laboratories, Inc, Lexington, Massachusetts, USA
| | - Vijeta Bhambhani
- Research and Development, Fractyl Laboratories, Inc, Lexington, Massachusetts, USA
| | - Guido Costamagna
- Digestive Endoscopy Unit, Fondazione Policlinico Universitario A. Gemelli IRCCS-Università Cattolica del Sacro Cuore, Rome, Italy
| | - Rehan Haidry
- Department of Gastroenterology, King's College Hospital, London, UK
| | - Eduardo Grecco
- Department of Surgery, ABC University, Medical School, São Paulo, Brazil
| | - Manoel Galvao Neto
- Department of Surgery, ABC University, Medical School, São Paulo, Brazil
| | - Guruprasad Aithal
- NIHR Nottingham Biomedical Research Centre, Ottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, UK
| | - Alessandro Repici
- Humanitas Clinical and Research Center - IRCCS, Rozzano, Italy
- Humanitas University, Department of Biomedical Sciences, Milan, Italy
| | - Bu'Hussain Hayee
- Department of Gastroenterology, King's College Hospital, London, UK
| | - Amyn Haji
- King's Institute of Therapeutic Endoscopy, King's College Hospital, London, UK
| | - A John Morris
- Department of Gastroenterology, Glasgow Royal Infirmary, Glasgow, UK
| | - Raf Bisschops
- Gastroenterology Department, University of Leuven, Leuven, Belgium
| | - Manil D Chouhan
- Division of Medicine, University College London Center for Medical Imaging, London, UK
| | - Naomi S Sakai
- Division of Medicine, University College London Center for Medical Imaging, London, UK
| | - Deepak L Bhatt
- Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Arun J Sanyal
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
| | - J J G H M Bergman
- Departments of Gastroenterology and Hepatology, Academic Medical Center Amsterdam, Amsterdam, The Netherlands
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Sakai NS, Bhagwanani A, Bray TJP, Hall-Craggs MA, Taylor SA. Assessment of body composition and association with clinical outcomes in patients with lung and colorectal cancer. BJR Open 2021; 3:20210048. [PMID: 35707759 PMCID: PMC9185845 DOI: 10.1259/bjro.20210048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/17/2021] [Accepted: 11/09/2021] [Indexed: 11/09/2022] Open
Abstract
Objectives: To assess body composition in patients with non-small cell lung cancer (NSCLC) and colorectal cancer using whole-body MRI and relate this to clinical outcomes. Methods: 53 patients with NSCLC (28 males, 25 females; mean age 66.9) and 74 patients with colorectal cancer (42 males, 32 females; mean age 62.9) underwent staging whole-body MRI scans, which were post-processed to derive fat mass (FM), fat free mass (FFM) and skeletal muscle (SM) indices and SM fat fraction (FF). These were compared between the two cancer cohorts using two-sided t-tests and the chi-squared test. Measurements of body composition were correlated with outcomes including length of hospital stay, metastatic status and mortality. Results: Patients with NSCLC had significantly lower FFM (p = 0.0071) and SM (p = 0.0084) indices. Mean SM FF was greater in patients with NSCLC (p = 0.0124) and was associated with longer hospital stay (p = 0.035). There was no significant relationship between FM, FFM and SM indices and length of hospital stay, metastatic status or mortality. Conclusions: Patients with NSCLC had lower FFM and SM indices than patients with colorectal cancer and greater SMFF, indicating lower SM mass with fatty infiltration. These findings reflect differences in the phenotype of the two groups and suggest patients with lung cancer are more likely to require additional nutritional support. Advances in knowledge: Body composition differs between NSCLC and colorectal cancer. Patients with NSCLC have both a reduced SM mass and greater SM FF suggesting that they are more nutritionally deplete than patients with colorectal cancer.
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Affiliation(s)
- Naomi S Sakai
- UCL Centre for Medical Imaging, London, UK
- University College London Hospital, London, UK
| | | | - Timothy JP Bray
- UCL Centre for Medical Imaging, London, UK
- University College London Hospital, London, UK
| | - Margaret A Hall-Craggs
- UCL Centre for Medical Imaging, London, UK
- University College London Hospital, London, UK
| | - Stuart Andrew Taylor
- UCL Centre for Medical Imaging, London, UK
- University College London Hospital, London, UK
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Mallett S, Allen AJ, Graziadio S, Taylor SA, Sakai NS, Green K, Suklan J, Hyde C, Shinkins B, Zhelev Z, Peters J, Turner PJ, Roberts NW, di Ruffano LF, Wolff R, Whiting P, Winter A, Bhatnagar G, Nicholson BD, Halligan S. At what times during infection is SARS-CoV-2 detectable and no longer detectable using RT-PCR-based tests? A systematic review of individual participant data. BMC Med 2020; 18:346. [PMID: 33143712 PMCID: PMC7609379 DOI: 10.1186/s12916-020-01810-8] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/08/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral ribonucleic acid (RNA) using reverse transcription polymerase chain reaction (RT-PCR) are pivotal to detecting current coronavirus disease (COVID-19) and duration of detectable virus indicating potential for infectivity. METHODS We conducted an individual participant data (IPD) systematic review of longitudinal studies of RT-PCR test results in symptomatic SARS-CoV-2. We searched PubMed, LitCOVID, medRxiv, and COVID-19 Living Evidence databases. We assessed risk of bias using a QUADAS-2 adaptation. Outcomes were the percentage of positive test results by time and the duration of detectable virus, by anatomical sampling sites. RESULTS Of 5078 studies screened, we included 32 studies with 1023 SARS-CoV-2 infected participants and 1619 test results, from - 6 to 66 days post-symptom onset and hospitalisation. The highest percentage virus detection was from nasopharyngeal sampling between 0 and 4 days post-symptom onset at 89% (95% confidence interval (CI) 83 to 93) dropping to 54% (95% CI 47 to 61) after 10 to 14 days. On average, duration of detectable virus was longer with lower respiratory tract (LRT) sampling than upper respiratory tract (URT). Duration of faecal and respiratory tract virus detection varied greatly within individual participants. In some participants, virus was still detectable at 46 days post-symptom onset. CONCLUSIONS RT-PCR misses detection of people with SARS-CoV-2 infection; early sampling minimises false negative diagnoses. Beyond 10 days post-symptom onset, lower RT or faecal testing may be preferred sampling sites. The included studies are open to substantial risk of bias, so the positivity rates are probably overestimated.
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Affiliation(s)
- Sue Mallett
- Centre for Medical Imaging, University College London, 2nd Floor, Charles Bell House, 43-45 Foley Street, London, W1W 7TS, UK.
| | - A Joy Allen
- NIHR In Vitro Diagnostics Co-operative, Newcastle University, Newcastle upon Tyne, NE2 7RU, UK
| | - Sara Graziadio
- NIHR In Vitro Diagnostics Co-operative, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, UK
| | - Stuart A Taylor
- Centre for Medical Imaging, University College London, 2nd Floor, Charles Bell House, 43-45 Foley Street, London, W1W 7TS, UK
| | - Naomi S Sakai
- Centre for Medical Imaging, University College London, 2nd Floor, Charles Bell House, 43-45 Foley Street, London, W1W 7TS, UK
| | - Kile Green
- NIHR In Vitro Diagnostics Co-operative, Newcastle University, Newcastle upon Tyne, NE2 7RU, UK
| | - Jana Suklan
- NIHR In Vitro Diagnostics Co-operative, Newcastle University, Newcastle upon Tyne, NE2 7RU, UK
| | - Chris Hyde
- Exeter Test Group, Institute of Health Research, University of Exeter Medical School, University of Exeter, College House, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Bethany Shinkins
- Test Evaluation Group, Academic Unit of Health Economics, Leeds Institute of Health Sciences, University of Leeds, Worsley Building , Clarendon Way, Leeds, LS2 9LJ, UK
| | - Zhivko Zhelev
- Exeter Test Group, Institute of Health Research, University of Exeter Medical School, University of Exeter, College House, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Jaime Peters
- Exeter Test Group, Institute of Health Research, University of Exeter Medical School, University of Exeter, College House, St Luke's Campus, Exeter, EX1 2LU, UK
| | - Philip J Turner
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Nia W Roberts
- Cancer Services, Gastroenterology, Population Health & Primary Care, Bodleian Health Care Libraries, University of Oxford, Oxford, OX2 6HT, UK
| | - Lavinia Ferrante di Ruffano
- Test Evaluation Research Group, Institute of Applied Health Research, University of Birmingham, Birmingham, B15 2TT, UK
| | | | - Penny Whiting
- Bristol Medical School, University of Bristol, Bristol, UK
| | - Amanda Winter
- NIHR In Vitro Diagnostics Co-operative, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE7 7DN, UK
| | | | - Brian D Nicholson
- Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK
| | - Steve Halligan
- Centre for Medical Imaging, University College London, 2nd Floor, Charles Bell House, 43-45 Foley Street, London, W1W 7TS, UK
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Bray TJP, Bainbridge A, Sakai NS, Hall-Craggs MA, Zhang H. An information-based comparison of diffusion attenuation models in normal and inflamed bone marrow. NMR Biomed 2020; 33:e4390. [PMID: 32749017 DOI: 10.1002/nbm.4390] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/16/2020] [Accepted: 07/18/2020] [Indexed: 06/11/2023]
Abstract
Diffusion-weighted imaging has received attention as a method for characterizing inflammatory exudates in bone marrow in immune-mediated inflammatory diseases and reveals an increase in diffusivity in regions of bone marrow oedema. Various models of diffusion attenuation have been investigated but the model providing the best description of tissue pathophysiology in regions of marrow oedema is unknown. Determining the most appropriate model is an important step towards protocol optimization and the development of a robust and clinically useful method. We aimed to determine which of three candidate models of diffusion attenuation most accurately describes the acquired signal from normal and inflamed bone marrow. 11 subjects with spondyloarthritis and evidence of active inflammation (ie bone marrow oedema) on MRI and 17 patients with no evidence of active inflammation underwent diffusion-weighted imaging of the sacroiliac joints (b-values 0, 50, 100, 300 and 600 s/mm2 ). Monoexponential, intravoxel incoherent motion (IVIM) and kurtosis models were fitted to the acquired signal from regions of interest in areas of bone marrow oedema and normal marrow. The three models were compared in terms of sum of squared error and information content (corrected Akaike information criterion). Model parameters were compared between regions of bone marrow oedema and regions of normal marrow. f the three models investigated, the IVIM model provided the best description of the signal over the 0-600 s/mm2 range across normal and inflamed bone marrow. There was a particular advantage of the IVIM model in normal marrow, where it was best able to capture the pronounced fast diffusion component observed in several cases. However, IVIM and kurtosis effects both became smaller and the signal behaviour became closer to monoexponential in the presence of bone marrow oedema. Our data suggest that increases in Dtissue (in the IVIM framework) might account for the reduced deviation from monoexponential behaviour in oedematous bone.
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Affiliation(s)
- Timothy J P Bray
- Centre for Medical Imaging, University College London, London, United Kingdom
| | - Alan Bainbridge
- Department of Medical Physics, University College London Hospitals, London, United Kingdom
| | - Naomi S Sakai
- Centre for Medical Imaging, University College London, London, United Kingdom
| | | | - Hui Zhang
- Department of Computer Science and Centre for Medical Image Computing, University College London, London, United Kingdom
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Abstract
The association between pancreatic fat, obesity and metabolic disease is well-documented, and although a potentially exciting target for novel therapies, remains poorly understood. Non-invasive quantitative imaging-derived biomarkers can provide insights into pathophysiology and potentially provide robust trial endpoints for development of new treatments. In this review, we provide an overview of the pathophysiology of non-alcoholic fatty pancreas disease and associations with metabolic factors, obesity and diabetes. We then explore approaches to pancreatic fat quantification using ultrasound, CT and MRI, reviewing the strengths, limitations and current published evidence in the assessment of pancreatic fat. Finally, we explore the broader challenges of pancreatic fat quantification as we move toward translating these methods into the clinical setting.
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Affiliation(s)
- Naomi S Sakai
- 1 UCL Centre for Medical Imaging, Division of Medicine, University College London , London , UK
| | - Stuart A Taylor
- 1 UCL Centre for Medical Imaging, Division of Medicine, University College London , London , UK
| | - Manil D Chouhan
- 1 UCL Centre for Medical Imaging, Division of Medicine, University College London , London , UK
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Sakai NS, Acharya V, Mansour S, Saleemi MA, Cheslyn-Curtis S. An unusual cause of small bowel obstruction caused by a Richter's-type hernia into the urinary bladder. Int J Surg Case Rep 2014; 5:358-60. [PMID: 24858979 PMCID: PMC4064428 DOI: 10.1016/j.ijscr.2014.04.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 04/23/2014] [Accepted: 04/23/2014] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION The authors present an unusual case of small bowel obstruction in a 62-year-old man. PRESENTATION OF CASE A 62-year-old man with a background of transitional cell carcinoma (TCC) of the bladder presented to the emergency department with abdominal pain, distension, vomiting and had not opened his bowels for three days. 3 weeks previously he had a repeat Transurtheral resection of bladder tumour (TURBT), during which there was an iatrogenic perforation of the bladder. A CT scan of the abdomen and pelvis revealed small bowel obstruction but did not identify a cause. At laparotomy the cause of the obstruction was identified as a section of the small bowel that had partially herniated into the bladder, via the perforation. The defect was repaired and the patient made an uneventful recovery. DISCUSSION Herniation of the bowel into a defect in the bladder wall is a rare event with only 6 previous cases reported in the literature. It can cause signs and symptoms of bowel obstruction. CONCLUSION In patients with known bladder perforations who present with symptoms and signs of bowel obstruction, bowel herniation into the bladder should be considered. Early surgical intervention may be necessary if the patient is clinically unwell with appropriate symptoms and signs and imaging does not provide conclusive answer.
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Affiliation(s)
- Naomi S Sakai
- Luton and Dunstable University Hospital, Lewsey Road, Luton LU4 0DZ, United Kingdom.
| | - Vikas Acharya
- Luton and Dunstable University Hospital, Lewsey Road, Luton LU4 0DZ, United Kingdom.
| | - Sami Mansour
- Luton and Dunstable University Hospital, Lewsey Road, Luton LU4 0DZ, United Kingdom.
| | - Mohammed A Saleemi
- Luton and Dunstable University Hospital, Lewsey Road, Luton LU4 0DZ, United Kingdom.
| | - Sarah Cheslyn-Curtis
- Luton and Dunstable University Hospital, Lewsey Road, Luton LU4 0DZ, United Kingdom.
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Sakai NS, Herman K, Shrestha D, Pittam M, Nayagam M, Ravichandran D. Intra-operative imprint cytology of sentinel lymph node: How many second operations are avoided? Eur J Surg Oncol 2014. [DOI: 10.1016/j.ejso.2014.02.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Sakai NS, Samia-Aly E, Barbera M, Fitzgerald RC. A review of the current understanding and clinical utility of miRNAs in esophageal cancer. Semin Cancer Biol 2013; 23:512-21. [PMID: 24013023 DOI: 10.1016/j.semcancer.2013.08.005] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Accepted: 08/27/2013] [Indexed: 12/31/2022]
Abstract
BACKGROUND MicroRNAs (miRNAs) are a class of small, well-conserved, non-coding RNAs that regulate the translation of RNAs. They have a role in biological and pathological process including cell differentiation, apoptosis, proliferation and metabolism. Since their discovery, they have been shown to have a potential role in cancer pathogenesis through their function as oncogenes or tumor suppressors. A substantial number of miRNAs show differential expression in esophageal cancer tissues, and so have been investigated for possible use in diagnosis. Furthermore, there is increasing interest in their use as prognostic markers and determining treatment response, as well as identifying their downstream targets and understanding their mode of action. METHODS We analyzed the most recent studies on miRNAs in esophageal cancer and/or Barrett's esophagus (BE). The publications were identified by searching in PuBMed for the following terms: Barrett's esophagus and microRNA; esophageal cancer and microRNA. RESULTS Four miRNAs (mi-R-25, -99a, -133a and -133b) showed good potential as diagnostic markers and interestingly five (mi-R-21, -27b, -126, - 143 and -145) appeared to be useful both as diagnostic and prognostic/predictive markers. CONCLUSION The data so far on miRNAs in esophageal carcinogenesis is promising but further work is required to determine whether miRNAs can be used as biomarkers, not only in the clinical setting or added to individualized treatment regimes but also in non-invasive test by making use of miRNAs identified in blood.
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Affiliation(s)
- Naomi S Sakai
- University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Box 111, Hills Road, Cambridge CB2 0SP, UK.
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