Context And Purpose: There is an urgent need to develop vitamin D dietary recommendations for dark-skinned populations resident at high latitude. Using data from randomised controlled trials (RCTs) with vitamin D-supplements/fortified foods, we undertook an individual participant data-level meta-regression (IPD) analysis of the response of wintertime serum 25-hydroxyvitamin (25(OH)D) to total vitamin D intake among dark-skinned children and adults residing at ≥ 40° N and derived dietary requirement values for vitamin D.
Methods: IPD analysis using data from 677 dark-skinned participants (of Black or South Asian descent; ages 5-86 years) in 10 RCTs with vitamin D supplements/fortified foods identified via a systematic review and predefined eligibility criteria.
Objectives: There is a need for updated haematological reference data in infancy. This study aimed to define intervals for haemoglobin and red blood cell biomarkers based on data from a large cohort of longitudinally followed Swedish infants.
Design: Longitudinal cohort study.
We evaluated the use of hyperpolarized C magnetic resonance imaging (MRI) in an open-chest rat model of myocardial infarction to image regional changes in myocardial metabolism. In total, 10 rats were examined before and after 30 minutes of occlusion of the left anterior descending coronary artery using hyperpolarized [1-C]pyruvate. Cardiac metabolic images of [1-C]pyruvate and its metabolites [1-C]lactate, [1-C]alanine, and [C]bicarbonate were obtained before and after ischemia.
View Article and Find Full Text PDFBackground High-quality non-invasive imaging of the deep venous system in the thorax is challenging, but nevertheless required for diagnosis of vascular pathology as well as for patient selection and preoperative planning for endovascular procedures. Purpose To compare the diagnostic quality of Gadofosveset-enhanced thoracic magnetic resonance venography, seven consecutive patients with suspected or known disease affecting the central thoracic veins were compared to seven consecutive magnetic resonance venography using conventional gadolinium-based contrast agents. Materials and methods Diagnostic capability, defined as the ability to assess vessel patency and pathologic conditions, for the major thoracic deep venous segments was assessed by two-independent readers.
View Article and Find Full Text PDFPurpose This study was performed to compare the diagnostic quality of Gadofosveset-enhanced magnetic resonance venography with Gadobutrol-enhanced magnetic resonance venography and computed tomography venography for the deep veins of the lower extremities in patients with iliocaval venous pathology. Materials and methods Diagnostic capability and image quality were assessed by two independent readers. Inter-reader variability was analyzed by unweighted and quadratic weighted Cohen's kappa values.
View Article and Find Full Text PDFObjectives: To evaluate if dietary vitamin D intake is adequate for sufficient vitamin D status during early winter in children living in Sweden, irrespective of latitude or skin color.
Methods: As part of a prospective, comparative, 2-center intervention study in northern (63°N) and southern (55°N) Sweden, dietary intake, serum 25-hydroxyvitamin D (S-25(OH) D), associated laboratory variables, and sociodemographic data were studied in 5 to 7-year-old children with fair and dark skin in November and December.
Results: Two hundred six children with fair/dark skin were included, 44/41 and 64/57 children in northern and southern Sweden, respectively.
Age-related decline in cardiac function can be prevented or postponed by lifelong endurance training. However, effects of normal ageing as well as of lifelong endurance exercise on longitudinal and radial contribution to stroke volume are unknown. The aim of this study was to determine resting longitudinal and radial pumping in elderly athletes, sedentary elderly and young sedentary subjects.
View Article and Find Full Text PDFBackground: An observational study has suggested that relapsing-remitting multiple sclerosis patients with helminth infections have lower disease activity and progression than uninfected multiple sclerosis patients.
Objective: To evaluate the safety and efficacy on MRI activity of treatment with TSO in relapsing MS.
Methods: The study was an open-label, magnetic resonance imaging assessor-blinded, baseline-to-treatment study including ten patients with relapsing forms of multiple sclerosis.
Aims: Overcrowding at pediatric emergency departments (EDs) may result in delayed clinical management and higher risks of medical error. This study was designed to prospectively evaluate what parents of sick children seek emergency care for and how these patients are being assessed and managed.
Methods: Patients aged 0 to 17 years seeking ED care at an urban Swedish university hospital, from 8 AM to 9 PM on 25 consecutive days, were included.
Purpose: The purpose of this retrospective study was to systematically search for acute adverse reactions and long-term complications in all patients that had been administered gadofosveset at our hospital.
Materials And Methods: We identified 67 gadofosveset administrations during 2006-2009 in 62 patients from 8 to 84years of age. Radiological information system (RIS) and clinical patient records were analyzed for suspected acute adverse reactions and long-term complications including nephrogenic systemic fibrosis (NSF).
Purpose: To use dynamic magnetic resonance spectroscopy (MRS) of hyperpolarized (13)C-pyruvate to follow the progress over time in vivo of breast cancer metabolism in the MMTV-PymT model, and to follow the response to the anti-estrogen drug tamoxifen.
Methods: Tumor growth was monitored by anatomical MRI by measuring tumor volumes. Dynamic MRS of hyperpolarized (13)C was used to measure an "apparent" pyruvate-to-lactate rate constant (kp) of lactate dehydrogenase (LDH) in vivo.
Aims: Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with substantial morbidity and mortality. AF is associated with enlargement of the left atrium (LA), and the LA volume has important prognostic implications for the disease. The objective of the study was to determine how measurements of LA volume and function obtained by transthoracic echocardiography (TTE), cardiac magnetic resonance (CMR), and 320-slice multi-detector computed tomography (MDCT) correlate in patients with permanent AF.
View Article and Find Full Text PDFPurpose: Although precise identification of the seizure-onset zone is an essential element of presurgical evaluation, source localization of ictal electroencephalography (EEG) signals has received little attention. The aim of our study was to estimate the accuracy of source localization of rhythmic ictal EEG activity using a distributed source model.
Methods: Source localization of rhythmic ictal scalp EEG activity was performed in 42 consecutive cases fulfilling inclusion criteria.
A change in myocardial metabolism is a known effect of several diseases. MRS with hyperpolarized (13)C-labelled pyruvate is a technique capable of detecting changes in myocardial pyruvate metabolism, and has proven to be useful for the evaluation of myocardial ischaemia in vivo. However, during fasting, the myocardial glucose oxidation is low and the fatty acid oxidation (β-oxidation) is high, which complicates the interpretation of pyruvate metabolism with the technique.
View Article and Find Full Text PDFUnlabelled: Elevated plasma N-terminal (NT)-proBNP from the heart as well as white matter hyperintensities (WMH) in the brain predict cardiovascular (CV) mortality in the general population. The cause of poor prognosis associated with elevated P-NT-proBNP is not known but WMH precede strokes in high risk populations. We assessed the association between P-NT-proBNP and WMH or brain atrophy measured with magnetic resonance imaging (MRI) in type 2 diabetic patients, and age-matched controls.
View Article and Find Full Text PDFActa Neurol Scand
December 2012
Objectives: The traditional view that multiple sclerosis (MS) is an autoimmune disease has recently been challenged by the claim that MS is caused by chronic cerebrospinal venous insufficiency (CCSVI). Although several studies have questioned this vascular theory, the CCSVI controversy is still ongoing. Our aim was to assess the prevalence of CCSVI in Danish MS patients using sonography and compare these findings with MRI measures of venous flow and morphology.
View Article and Find Full Text PDFThe branched chain amino acid transaminase (BCAT) has an important role in nitrogen shuttling and glutamate metabolism in the brain. The purpose of this study was to describe the cerebral distribution and metabolism of hyperpolarized 2-keto[1-(13)C]isocaproate (KIC) in the normal rat using magnetic resonance modalities. Hyperpolarized KIC is metabolized to [1-(13)C]leucine (leucine) by BCAT.
View Article and Find Full Text PDFHuman micturition is physiologically controlled via a complex and finely tuned network of cortical and subcortical regions, hitherto not fully understood. We report the case of a 42-year-old man with juvenile myoclonic epilepsy (JME) and post-traumatic epilepsy. Ictal enuresis was the only manifestation of the de novo post-traumatic simple autonomic seizures.
View Article and Find Full Text PDFUgeskr Laeger
February 2011
In this systematic review of the literature, we reviewed the evidence for maintaining the current recommendation that a routine CT scan should be performed in first-episode psychotic patients (Danish National Board of Health). We identified eight papers comprising 625 CT and 214 MRI scans. The share of potentially causal brain abnormalities was 0.
View Article and Find Full Text PDFDuring childhood and adolescence, ongoing white matter maturation in the fronto-parietal cortices and connecting fiber tracts is measurable with diffusion-weighted imaging. Important questions remain, however, about the links between these changes and developing cognitive functions. Spatial working memory (SWM) performance improves significantly throughout the childhood years, and several lines of evidence implicate the left fronto-parietal cortices and connecting fiber tracts in SWM processing.
View Article and Find Full Text PDFCognitive control of thoughts, actions and emotions is important for normal behaviour and the development of such control continues throughout childhood and adolescence. Several lines of evidence suggest that response inhibition is primarily mediated by a right-lateralized network involving inferior frontal gyrus (IFG), presupplementary motor cortex (preSMA), and subthalamic nucleus. Though the brain's fibre tracts are known to develop during childhood, little is known about how fibre tract development within this network relates to developing behavioural control.
View Article and Find Full Text PDFRationale And Objectives: Inhaled hyperpolarized (3)He magnetic resonance (MR) imaging has been used to measure alveolar size in patients with emphysema. The aim of this study was to test the hypothesis that (3)He MR images could be used to develop a biomarker of emphysema progression.
Materials And Methods: Twelve healthy controls and 18 patients with emphysema (eight current smokers, 10 ex-smokers) were imaged at baseline and 6 and 12 months.
Purpose: To compare apparent diffusion coefficient (ADC) measurements from hyperpolarized (HP) helium ((3)He)-magnetic resonance imaging (MRI) with quantitative data from multislice Computed Tomography (CT) (MSCT) of the whole lungs and pulmonary function tests (PFT).
Materials And Methods: Twenty-seven subjects, 22 with established emphysema and 5 with preclinical emphysema defined by PFT criteria, were examined with HP (3)He-MRI and MSCT. Mean age was 55 (+/-12) years, 18 female and 9 male.
Pyruvate is included in the energy production of the heart muscle and is metabolized into lactate, alanine, and CO(2) in equilibrium with HCO(3) (-). The aim of this study was to evaluate the feasibility of using (13)C hyperpolarization enhanced MRI to monitor pyruvate metabolism in the heart during an ischemic episode. The left circumflex artery of pigs (4 months, male, 29-34 kg) was occluded for 15 or 45 min followed by 2 hr of reperfusion.
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