Publications by authors named "Bryan Haddock"

Background And Hypothesis: The kidneys may be susceptible to ectopic fat and its lipotoxic effects, disposing them to chronic kidney disease (CKD) in type 2 diabetes (T2D). We investigated whether the kidney parenchyma fat content and kidney sinus fat volume would be higher in persons with T2D and CKD.

Methods: Cross-sectional study including 29 controls, 27 persons with T2D and no CKD, and 48 persons with T2D and early CKD (urine albumin creatinine ratio (UACR) ≥ 30 mg/g).

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Introduction: Accurately estimating bone perfusion and metabolism using [F]NaF kinetics from shorter scan times could help address concerns related to patient comfort, motion, and throughput for PET scans. We examined the impact of changing the PET scan duration on the accuracy of [F]NaF kinetic parameters in the knee.

Methods: Both knees of twenty participants with and without osteoarthritis were scanned using a hybrid PET-MRI system (53 ± 13 years, BMI 25.

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The accurate estimation of the tracer arterial blood concentration is crucial for reliable quantitative kinetic analysis in PET. In the current work, we demonstrate the automatic extraction of an image-derived input function (IDIF) from a CT AI-based aorta segmentation subsequently resliced to a dynamic PET series acquired on a Siemens Vision Quadra long-axial field of view scanner in 10 human subjects scanned with [O]HO. We demonstrate that the extracted IDIF is quantitative and in excellent agreement with a delay- and dispersion-corrected sampled arterial input function (AIF).

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In order to support or refute the clinical suspicion of cranial giant cell arteritis (GCA), a supplemental imaging modality is often required. High-resolution black blood Magnetic Resonance Imaging (BB MRI) techniques with contrast enhancement can visualize artery wall inflammation in GCA. We compared findings on BB MRI without contrast enhancement with findings on 2-deoxy-2-[F]fluoro-D-glucose positron emission tomography/low-dose computed tomography (2-[F]FDG PET/CT) in ten patients suspected of having GCA and in five control subjects who had a 2-[F]FDG PET/CT performed as a routine control for malignant melanoma.

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Objective: Visceral fat mass (VFM) is a risk factor for cardiovascular diseases, type 2 diabetes mellitus, and malignancy; however, normative data are limited. The aim of this study was to provide reference data for VFM from a large, apparently healthy Caucasian adult population.

Methods: Volunteers aged 20 to 93 years from the Copenhagen City Heart Study had a standardized whole-body dual-energy x-ray absorptiometry scan performed using the iDXA (GE Lunar).

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Aim: To investigate the effects of ezetimibe on the urine albumin creatinine ratio (UACR) and kidney parenchyma fat content (kidney-PF) in individuals with type 2 diabetes (T2D) and early chronic kidney disease.

Materials And Methods: A randomized, double-blind, placebo-controlled study of ezetimibe 10 mg once daily for 16 weeks in individuals with T2D and a UACR of 30 mg/g or higher was conducted. Kidney-PF was assessed with magnetic resonance spectroscopy.

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Chronic kidney disease (CKD) is a major population disease. In diabetes as well as hypertension, kidney disease is one of the most serious complications. Recent research has demonstrated that chronic hypoxia is a key actor in the pathogenesis of CKD.

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Background: We used magnetic resonance imaging (MRI) to study kidney energetics in persons with and without type 1 diabetes (T1D).

Methods: In a cross-sectional study, 15 persons with T1D and albuminuria and 15 non-diabetic controls (CONs) underwent multiparametric MRI (3 Tesla Philips Scanner) to quantify renal cortical and medullary oxygenation (R*, higher values correspond to higher deoxyhaemoglobin concentration), renal perfusion (arterial spin labelling) and renal artery blood flow (phase contrast). Analyses were adjusted for age, sex, systolic blood pressure, plasma haemoglobin, body mass index and estimated glomerular filtration rate (eGFR).

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Background GLP-1 (glucagon-like peptide-1) receptor agonists exert beneficial long-term effects on cardiovascular and renal outcomes. In humans, the natriuretic effect of GLP-1 depends on GLP-1 receptor interaction, is accompanied by suppression of angiotensin II, and is independent of changes in renal plasma flow. In rodents, angiotensin II constricts vasa recta and lowers medullary perfusion.

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Public health policies aimed at obesity reduction are more often directed toward adults than children. This is alarming given that rates of childhood obesity have been steadily increasing, and, if not treated early, adolescents with obesity may develop comorbidities into adulthood. Lifestyle-based interventions are the cornerstone of childhood obesity treatment.

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Background: Chronic low-grade inflammation has been suggested as one of the key elements in the development of sarcopenia, but in contrast to disease-related loss of muscle mass, the role of chronic low-grade inflammation in age-related (primary) sarcopenia is still not clear. The aim of this study was to investigate low-grade inflammation in relation to age and the potential association between inflammatory biomarkers and body composition, muscle strength and physical performance in a healthy Danish cohort.

Methods: There were 1160 generally healthy men and women (range: 22-93 years) included.

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Background: Although growth differentiation factor 15 (GDF15) is known to increase with disease and is associated with low physical performance, the role of GDF15 in normal ageing is still not fully understood. Specifically, the influence of circulating GDF15 on impairments in maximal muscle power (a major contributor to functional limitations) and the underlying components has not been investigated.

Methods: Data from 1305 healthy women and men aged 20 to 93 years from The Copenhagen Sarcopenia Study were analysed.

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Background: Inhibitors of the sodium-glucose cotransporter 2 (SGLT2) slow the progression of diabetic kidney disease, possibly by reducing the proximal tubule transport workload with subsequent improvement of renal oxygenation. We aimed to test this hypothesis in individuals with type 1 diabetes and albuminuria.

Methods: A randomised, double-blind, placebo-controlled, crossover trial with a single 50 mg dose of the SGLT2 inhibitor dapagliflozin and placebo in random order, separated by a two-week washout period.

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Background: The 30-s sit-to-stand (STS) muscle power test is a valid test to assess muscle power in older people; however, whether it may be used to assess trajectories of lower-limb muscle power through the adult lifespan is not known. This study evaluated the pattern and time course of variations in relative, allometric and specific STS muscle power throughout the lifespan.

Methods: Subjects participating in the Copenhagen Sarcopenia Study (729 women and 576 men; aged 20 to 93 years) were included.

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MRI can provide fundamental tools in decoding physiological stressors stimulated by training paradigms. Acute physiological changes induced by three diverse exercise protocols known to elicit similar levels of muscle hypertrophy were evaluated using muscle functional magnetic resonance imaging (mfMRI). The study was a cross-over study with participants ( = 10) performing three acute unilateral knee extensor exercise protocols to failure and a work matched control exercise protocol.

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Background: Phase-contrast (PC) MRI is a feasible and valid noninvasive technique to measure renal artery blood flow, showing potential to support diagnosis and monitoring of renal diseases. However, the variability in measured renal blood flow values across studies is large, most likely due to differences in PC-MRI acquisition and processing. Standardized acquisition and processing protocols are therefore needed to minimize this variability and maximize the potential of renal PC-MRI as a clinically useful tool.

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This study aimed to assess the validity and functional relevance of a standardized procedure to assess lower limb muscle power by means of the 30-s sit-to-stand (STS) test when compared to leg extension power (LEP), traditional STS performance and handgrip strength. A total of 628 community-dwelling older subjects (60-93 years) from the Copenhagen Sarcopenia Study were included. Physical performance was assessed by the 30-s STS and 10-m maximal gait speed tests.

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Important physiological quantities for investigating muscle hypertrophy include blood oxygenation, cell swelling, and changes in blood flow. The purpose of this study was to compare the acute changes of these parameters in human skeletal muscle induced by low-load (20% 1-RM) blood flow-restricted (BFR-20) knee extensor exercise compared with free-flow work-matched (FF-20) and free-flow 50% 1-RM (FF-50) knee extensor exercise using multimodal magnetic resonance imaging (MRI). Subjects ( = 11) completed acute exercise sessions for each exercise mode in an MRI scanner, where interleaved measures of muscle (indicator of edema), [Formula: see text] (indicator of deoxyhemoglobin), macrovascular blood flow, and diffusion were performed before, between sets, and after the final set for each exercise protocol.

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Background: We investigated the impact of obesity on responses to high intensity interval exercise (HIIE) on hunger and energy intake (EI) in young men.

Methods: Ten men with obesity (OB) (Body Mass Index [BMI]: 34.6±4.

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Background: Our main goal was to evaluate the pattern and time course of changes in relative muscle power and its constituting components throughout the life span.

Methods: A total of 1,305 subjects (729 women and 576 men; aged 20-93 years) participating in the Copenhagen Sarcopenia Study took part. Body mass index (BMI), leg lean mass assessed by dual-energy X-ray absorptiometry (DXA), and leg extension muscle power (LEP) assessed by the Nottingham power rig were recorded.

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Objective And Background: The diagnostic criteria of episodic and chronic cluster headache (cCH) were recently modified, yet pathophysiological differences between the two are still unclear. The aim of this cross-sectional study is to identify and characterize other differences between episodic and cCH.

Methods: Data from a retrospective, questionnaire- and interview-based study were analyzed with a focus on associated factors including traumatic head injury (THI), familial history, and change of phenotype.

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Background: Computed tomography (CT) scans are routinely performed in positron emission tomography (PET) and single photon emission computed tomography (SPECT) examinations globally, yet few surveys have been conducted to gather national diagnostic reference level (NDRL) data for CT radiation doses in positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/computed tomography (SPECT/CT). In this first Nordic-wide study of CT doses in hybrid imaging, Nordic NDRL CT doses are suggested for PET/CT and SPECT/CT examinations specific to the clinical purpose of CT, and the scope for optimisation is evaluated. Data on hybrid imaging CT exposures and clinical purpose of CT were gathered for 5 PET/CT and 8 SPECT/CT examinations via designed booklet.

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To develop technical recommendations on the acquisition and post-processing of renal longitudinal (T1) and transverse (T2) relaxation time mapping. A multidisciplinary panel consisting of 18 experts in the field of renal T1 and T2 mapping participated in a consensus project, which was initiated by the European Cooperation in Science and Technology Action PARENCHIMA CA16103. Consensus recommendations were formulated using a two-step modified Delphi method.

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Background: Despite no international consensus on the diagnostic criteria for sarcopenia, low lean mass, muscle strength, and physical function are important risk factors for disability, frailty, and mortality in older individuals, as well as in a wide range of patients with muscle loss. Here, we provide a population-based reference material of total and regional lean body mass, muscle strength/power parameters, and physical function in a healthy cohort of Danish men and women across the lifespan.

Methods: Volunteers aged 20-93 years from the Copenhagen City Heart Study were invited to establish a Danish reference material (Copenhagen Sarcopenia Study) on lean mass characteristics [appendicular lean mass (ALM), iDXA, GE Lunar], muscle function [handgrip strength (HGS), Jamar dynamometer and leg extension power (LEP), Nottingham Power Rig], and physical function [30 s sit-to-stand test (STS), 10-m maximal and habitual gait speed (GS)].

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Purpose: The acute effect of loading on bone tissue and physiology can offer important information with regard to joint function in diseases such as osteoarthritis. Imaging studies using [F]-sodium fluoride ([F]NaF) have found changes in tracer kinetics in animals after subjecting bones to strain, indicating an acute physiological response. The aim of this study is to measure acute changes in NaF uptake in human bone due to exercise-induced loading.

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