[F]Fluoride uptake in various bone types and soft tissues in rat.

Background: In the development of new F-labelled tracers, it is important to assess the amount of released [F]fluoride taken up in the bones of experimental animals because all F-labelled PET-tracers are prone, to lesser or higher degree, to undergo defluorination, with subsequent release of [F]fluoride during scanning. However, the pharmacokinetics of [F]fluoride in bones and other organs of healthy rats have not been well documented in a comprehensive manner. We aimed to study pharmacokinetics of [F]NaF in rats in order to increase our understanding of the biodistribution of [F]fluoride originating from defluorination of F-labelled tracers.

Changes in electrocardiogram parameters during acute nonshivering cold exposure and associations with brown adipose tissue activity, plasma catecholamine levels, and brachial blood pressure in healthy adults.

Background: Sympathetic activity causes changes in electrocardiogram (ECG) during cold exposure and the changes have been studied mostly during hypothermia and less during mild acute nonshivering cold exposure. Cold-induced sympathetic activity also activates brown adipose tissue (BAT) and increases arterial blood pressure (BP) and plasma catecholamine levels. We examined changes in ECG parameters during acute nonshivering cold exposure and their associations with markers of sympathetic activity during cold exposure: brachial blood pressure (BP), plasma catecholamine levels, and BAT activity measured by positron emission tomography (PET).

Associations Between Brain Gray Matter Volumes and Adipose Tissue Metabolism in Healthy Adults.

Objective: Gray matter (GM) volume in different brain loci has been shown to vary in obesity and diabetes, and elevated fasting plasma nonesterified fatty acid (NEFA) levels have been suggested as one potential mechanism. The hypothesis presented in this study is that brown adipose tissue (BAT) activity may correlate with GM volume in areas negatively associated with obesity and diabetes.

Methods: A total of 36 healthy patients (M/F: 12/24, age 39.

Therapeutic Antibody Against Phosphorylcholine Preserves Coronary Function and Attenuates Vascular F-FDG Uptake in Atherosclerotic Mice.

This study showed that treatment with a therapeutic monoclonal immunoglobulin-G1 antibody against phosphorylcholine on oxidized phospholipids preserves coronary flow reserve and attenuates atherosclerotic inflammation as determined by the uptake of F-fluorodeoxyglucose in atherosclerotic mice. The noninvasive imaging techniques represent translational tools to assess the efficacy of phosphorylcholine-targeted therapy on coronary artery function and atherosclerosis in clinical studies.

High Brown Fat Activity Correlates With Cardiovascular Risk Factor Levels Cross-Sectionally and Subclinical Atherosclerosis at 5-Year Follow-Up.

Objective: Brown adipose tissue (BAT) activity correlates negatively with obesity and insulin resistance, and BAT has been suggested to act as a protective factor against atherogenesis. We aimed to examine subclinical atherosclerosis and risk factor levels in a group of individuals who had 5 years earlier participated in positron-emission tomography studies with measurements of BAT activity. Approach and Results: Study cohort (males/females=5/26, baseline age 41.

Effects of short-term sprint interval and moderate-intensity continuous training on liver fat content, lipoprotein profile, and substrate uptake: a randomized trial.

Type 2 diabetes (T2D) and increased liver fat content (LFC) alter lipoprotein profile and composition and impair liver substrate uptake. Exercise training mitigates T2D and reduces LFC, but the benefits of different training intensities in terms of lipoprotein classes and liver substrate uptake are unclear. The aim of this study was to evaluate the effects of moderate-intensity continuous training (MICT) or sprint interval training (SIT) on LFC, liver substrate uptake, and lipoprotein profile in subjects with normoglycemia or prediabetes/T2D.

Influence of transport line material on the molar activity of cyclotron produced [F]fluoride.

Introduction: Production of fluorine-18-labeled radiopharmaceuticals is always associated with the varying levels of the same compound containing stable fluorine-19. In practice, this affects the molar activity (A), defined as amount of radioactivity divided by the molar quantity (Bq/mol). We have focused on studying how the material of the transport tubing connecting the cyclotron target chamber to the synthesis device affects the concentration of fluoride in the water arriving to the reaction vessel and subsequently the A of the fluorine-18 labeled radiopharmaceuticals produced.

Automated production of [ F]FTHA according to GMP.

14-(R,S)-[ F]fluoro-6-thia-heptadecanoic acid is a tracer for fatty acid imaging by positron emission tomography. High demand for this tracer required us to replace semiautomatic synthesis with a fully automated procedure. An automated synthesis device was constructed in-house for multistep nucleophilic F-fluorination and a control system was developed.

Effects of atorvastatin and diet interventions on atherosclerotic plaque inflammation and [F]FDG uptake in LdlrApob mice.

Background And Aims: Uptake of the positron emission tomography (PET) tracer 2-deoxy-2-[F]-fluoro-d- glucose ([F]FDG) into macrophages is a sensitive marker of inflammation in atherosclerosis. To assess the anti-inflammatory effects of statins, we studied whether atorvastatin therapy reduces aortic [F]FDG uptake in hypercholesterolemic mice deficient in low-density lipoprotein receptor (Ldlr), and expressing only apolipoprotein B-100 (LdlrApob).

Methods: Thirty-six LdlrApob mice were fed a high-fat diet (HFD) for 12 weeks and then allocated to receive a HFD (n = 13), chow diet (Chow, n = 12), or HFD with added atorvastatin (HFD + A, n = 11), for another 12 weeks.

Two weeks of moderate-intensity continuous training, but not high-intensity interval training, increases insulin-stimulated intestinal glucose uptake.

Similar to muscles, the intestine is also insulin resistant in obese subjects and subjects with impaired glucose tolerance. Exercise training improves muscle insulin sensitivity, but its effects on intestinal metabolism are not known. We studied the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on intestinal glucose and free fatty acid uptake from circulation in humans.

Parametric Binding Images of the TSPO Ligand 18F-DPA-714.

Unlabelled: F-labeled N,N-diethyl-2-(2-[4-(2-fluoroethoxy)phenyl]-5,7-dimethylpyrazolo[1,5-α]pyrimidine-3-yl)acetamide (DPA-714) is a radioligand for the 18-kDa translocator protein. The purpose of the present study was to identify the best method for generating quantitative parametric images of F-DPA-714 binding.

Methods: Ninety-minute dynamic F-DPA-714 PET scans with full arterial sampling from 6 healthy subjects and 9 Alzheimer disease (AD) patients were used.

18-kDa translocator protein ligand F-FEMPA: Biodistribution and uptake into atherosclerotic plaques in mice.

Background: Radioligands of 18-kDa translocator protein (TSPO) expressed on activated macrophages are a potential approach for imaging of inflammation in atherosclerosis. We evaluated a novel TSPO-targeted tracer F-FEMPA for the detection of atherosclerotic plaque inflammation in mice.

Methods And Results: The distribution kinetics of F-FEMPA was evaluated by in vivo PET/CT imaging.

Human brown adipose tissue [(15)O]O2 PET imaging in the presence and absence of cold stimulus.

Purpose: Brown adipose tissue (BAT) is considered a potential target for combatting obesity, as it produces heat instead of ATP in cellular respiration due to uncoupling protein-1 (UCP-1) in mitochondria. However, BAT-specific thermogenic capacity, in comparison to whole-body thermogenesis during cold stimulus, is still controversial. In our present study, we aimed to determine human BAT oxygen consumption with [(15)O]O2 positron emission tomography (PET) imaging.

Resistance training enhances insulin suppression of endogenous glucose production in elderly women.

An altered prenatal environment during maternal obesity predisposes offspring to insulin resistance, obesity, and their consequent comorbidities, type 2 diabetes and cardiovascular disease. Telomere shortening and frailty are additional risk factors for these conditions. The aim of this study was to evaluate the effects of resistance training on hepatic metabolism and ectopic fat accumulation.

Effect of Bariatric Surgery on Adipose Tissue Glucose Metabolism in Different Depots in Patients With or Without Type 2 Diabetes.

Objective: We investigated fat distribution and tissue-specific insulin-stimulated glucose uptake (GU) in seven fat compartments (visceral and subcutaneous) and skeletal muscle in morbidly obese patients with (T2D) and without (ND) type 2 diabetes before and 6 months after bariatric surgery.

Research Design And Methods: A total of 23 obese patients (BMI 43.0 ± 3.

68Ga-DOTA-Siglec-9--a new imaging tool to detect synovitis.

Introduction: Vascular adhesion protein-1 (VAP-1) is an adhesion molecule, which upon inflammation is rapidly translocated from intracellular sources to the endothelial cell surface. We have recently discovered that sialic acid- binding immunoglobulin-like lectin 9 (Siglec-9) is a leukocyte ligand of VAP-1 and that 68Ga-labeled Siglec-9 motif peptide facilitates in vivo imaging of inflammation. This study evaluated the feasibility of 68Ga-DOTA-Siglec-9 positron emission tomography (PET) for the assessment of synovitis.

Resistance training improves skeletal muscle insulin sensitivity in elderly offspring of overweight and obese mothers.

Aims/hypothesis: Maternal obesity predisposes offspring to adulthood morbidities, including type 2 diabetes. Type 2 diabetes and insulin resistance have been associated with shortened telomere length. First, we aimed to investigate whether or not maternal obesity influences insulin sensitivity and its relationship with leucocyte telomere length (LTL) in elderly women.

[18F]FDG Accumulation in Early Coronary Atherosclerotic Lesions in Pigs.

Objective: Inflammation is an important contributor to atherosclerosis progression. A glucose analogue 18F-fluorodeoxyglucose ([18F]FDG) has been used to detect atherosclerotic inflammation. However, it is not known to what extent [18F]FDG is taken up in different stages of atherosclerosis.

Quantification of [18F]DPA-714 binding in the human brain: initial studies in healthy controls and Alzheimer's disease patients.

Fluorine-18 labelled N,N-diethyl-2-(2-[4-(2-fluoroethoxy)phenyl]-5,7-dimethylpyrazolo[1,5-α]pyrimidine-3-yl)acetamide ([(18)F]DPA-714) binds to the 18-kDa translocator protein (TSPO) with high affinity. The aim of this initial methodological study was to develop a plasma input tracer kinetic model for quantification of [(18)F]DPA-714 binding in healthy subjects and Alzheimer's disease (AD) patients, and to provide a preliminary assessment whether there is a disease-related signal. Ten AD patients and six healthy subjects underwent a dynamic positron emission tomography (PET) study along with arterial sampling and a scan protocol of 150 minutes after administration of 250 ± 10 MBq [(18)F]DPA-714.

Obesity-associated intestinal insulin resistance is ameliorated after bariatric surgery.

Aims/hypothesis: The intestine is the main site for glucose absorption and it has been suggested that it exhibits insulin resistance. Bariatric surgery has been shown to reverse insulin resistance and type 2 diabetes, but its effects on human intestinal metabolism are unknown. Our aim was to evaluate the effects of insulin on intestinal glucose metabolism before and after bariatric surgery.

Weight loss after bariatric surgery reverses insulin-induced increases in brain glucose metabolism of the morbidly obese.

Obesity and insulin resistance are associated with altered brain glucose metabolism. Here, we studied brain glucose metabolism in 22 morbidly obese patients before and 6 months after bariatric surgery. Seven healthy subjects served as control subjects.

Effects of age, diet, and type 2 diabetes on the development and FDG uptake of atherosclerotic plaques.

Objectives: This study investigated the effects of age, duration of a high-fat diet, and type 2 diabetes on atherosclerotic plaque development and uptake of (18)F-fluorodeoxyglucose ((18)F-FDG) in 2 mouse models.

Background: The animal's age and start time and duration of a high-fat diet have effects on plaque composition in atherosclerotic mice.

Methods: The aortas of atherosclerotic low-density lipoprotein receptor deficient mice expressing only apolipoprotein B100 (LDLR(-/-)ApoB(100/100)) and atherosclerotic and diabetic mice overexpressing insulin-like growth factor II (IGF-II/LDLR(-/-)ApoB(100/100)) were investigated at 4, 6, and 12 months of age and older after varying durations of high-fat diet.

[(11)C]PIB-, [(18)F]FDG-PET and MRI imaging in patients with Parkinson's disease with and without dementia.

The objective of this study was to identify possible group differences between PD patients with dementia and without dementia by combining different functional and structural imaging methods in vivo, which might provide an opportunity to disentangle the pathophysiological correlates of cognitive impairment and dementia in PD. We performed a neuropsychological evaluation, structural brain MRI, [(18)F]FDG PET and [(11)C]PIB PET in 19 PD patients [eight non-demented (PD), eleven demented (PDD)] and 24 healthy elderly volunteers. [(11)C]PIB region-to-cerebellum ratios did not differ significantly between the groups in any brain region (p > 0.

Cognitive reserve hypothesis: Pittsburgh Compound B and fluorodeoxyglucose positron emission tomography in relation to education in mild Alzheimer's disease.

Objective: The reduced risk for Alzheimer's disease (AD) in high-educated individuals has been proposed to reflect brain cognitive reserve, which would provide more efficient compensatory mechanisms against the underlying pathology, and thus delayed clinical expression. Our aim was to find possible differences in brain amyloid ligand 11C-labeled Pittsburgh Compound B ([11C]PIB) uptake and glucose metabolism in high- and low-educated patients with mild AD.

Methods: Twelve high-educated and 13 low-educated patients with the same degree of cognitive deterioration were studied with PET using [11C]PIB and 18F-fluorodeoxyglucose as ligands.