Assessment of hepatic transporter function in rats using dynamic gadoxetate-enhanced MRI: a reproducibility study.

Objective: Previous studies have revealed a substantial between-centre variability in DCE-MRI biomarkers of hepatocellular function in rats. This study aims to identify the main sources of variability by comparing data measured at different centres and field strengths, at different days in the same subjects, and over the course of several months in the same centre.

Materials And Methods: 13 substudies were conducted across three facilities on two 4.

New improved radiometabolite analysis method for [F]FTHA from human plasma: a test-retest study with postprandial and fasting state.

Background: Fatty acid uptake can be measured using PET and 14-(R,S)-[F]fluoro-6-thia-heptadecanoic acid ([F]FTHA). However, the relatively rapid rate of [F]FTHA metabolism significantly affects kinetic modeling of tissue uptake. Thus, there is a need for accurate chromatographic methods to analyze the unmetabolized [F]FTHA (parent fraction).

Salivary metabolomics in patients with oral lichen planus: a preliminary study based on NMR spectroscopy.

Objectives: The present preliminary study aimed to investigate the salivary metabolic profile in patients with asymptomatic oral lichen planus (OLP) using nuclear magnetic resonance (NMR) spectroscopy.

Material And Methods: Stimulated whole mouth saliva (SWMS) samples were collected from 15 reticular OLP female patients and 15 from age- and sex-matched controls (HCs). A total of 23 metabolites were identified and quantified.

Use of In Vivo Imaging and Physiologically-Based Kinetic Modelling to Predict Hepatic Transporter Mediated Drug-Drug Interactions in Rats.

Gadoxetate, a magnetic resonance imaging (MRI) contrast agent, is a substrate of organic-anion-transporting polypeptide 1B1 and multidrug resistance-associated protein 2. Six drugs, with varying degrees of transporter inhibition, were used to assess gadoxetate dynamic contrast enhanced MRI biomarkers for transporter inhibition in rats. Prospective prediction of changes in gadoxetate systemic and liver AUC (AUCR), resulting from transporter modulation, were performed by physiologically-based pharmacokinetic (PBPK) modelling.

Imaging of the Glucose-Dependent Insulinotropic Polypeptide Receptor Using a Novel Radiolabeled Peptide Rationally Designed Based on Endogenous GIP and Synthetic Exendin-4 Sequences.

Imaging and radiotherapy targeting the glucose-dependent insulinotropic polypeptide receptor (GIPR) could potentially benefit the management of neuroendocrine neoplasms (NENs), complementing clinically established radiopharmaceuticals. The aim of this study was to evaluate a GIPR-targeting positron emission tomography (PET) radioligand with receptor-specific binding, fast blood clearance, and low liver background uptake. The peptide DOTA-bioconjugate, C803-GIP, was developed based on the sequence of the endogenous GIP(1-30) and synthetic exendin-4 peptides with selective amino acid mutations to combine their specificity for the GIPR and in vivo stability, respectively.

Prognostic value of P-wave morphology in general population.

Aims: To evaluate the prognostic significance of novel P-wave morphology descriptors in general population.

Methods And Results: Novel P-wave morphology variables were analyzed from orthogonal X-, Y-, Z-leads of the digitized electrocardiogram using a custom-made software in 6906 middle-aged subjects of the Mini-Finland Health Survey. A total of 3747 (54.

Preoperative measures predicting outcome after pancreatic resection in aged patients.

Background And Objective: High-risk surgery on aged patients raises challenging ethical and clinical issues. The aim of this study was to analyze the preoperative factors associated with severe complications and returning home after pancreatic resection among patients aged ⩾ 75 years.

Patients And Methods: Patients aged ⩾ 75 years undergoing pancreatic resection in 2012-2019 were retrospectively searched from the hospital database.

Glucagonlike Peptide-1 Receptor Imaging in Individuals with Type 2 Diabetes.

The glucagonlike peptide-1 receptor (GLP1R) is a gut hormone receptor, intricately linked to regulation of blood glucose homeostasis via several mechanisms. It is an established and emergent drug target in metabolic disease. The PET radioligand Ga-DO3A-VS-exendin4 (Ga-exendin4) has the potential to enable longitudinal studies of GLP1R in the human pancreas.

Drug Occupancy Assessment at the Glucose-Dependent Insulinotropic Polypeptide Receptor by Positron Emission Tomography.

Targeting of the glucose-dependent insulinotropic polypeptide receptor (GIPR) is an emerging strategy in antidiabetic drug development. The aim of this study was to develop a positron emission tomography (PET) radioligand for the GIPR to enable the assessment of target distribution and drug target engagement in vivo. The GIPR-selective peptide S02-GIP was radiolabeled with Ga.

Triantennary GalNAc Molecular Imaging Probes for Monitoring Hepatocyte Function in a Rat Model of Nonalcoholic Steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a progressive form of nonalcoholic fatty liver disease that can lead to irreversible liver cirrhosis and cancer. Early diagnosis of NASH is vital to detect disease before it becomes life-threatening, yet noninvasively differentiating NASH from simple steatosis is challenging. Herein, bifunctional probes have been developed that target the hepatocyte-specific asialoglycoprotein receptor (ASGPR), the expression of which decreases during NASH progression.

Imaging of the Glucagon Receptor in Subjects with Type 2 Diabetes.

Despite the importance of the glucagon receptor (GCGR) in disease and in pharmaceutical drug development, there is a lack of specific and sensitive biomarkers of its activation in humans. The PET radioligand Ga-DO3A-VS-Tuna-2 (Ga-Tuna-2) was developed to yield a noninvasive imaging marker for GCGR target distribution and drug target engagement in humans. The biodistribution and dosimetry of Ga-Tuna-2 was assessed by PET/CT in 13 individuals with type 2 diabetes as part of a clinical study assessing the occupancy of the dual GCGR/glucagon like peptide-1 receptor agonist SAR425899.

Receptor occupancy of dual glucagon-like peptide 1/glucagon receptor agonist SAR425899 in individuals with type 2 diabetes.

Unimolecular dual agonists for the glucagon-like peptide 1 receptor (GLP1R) and glucagon receptor (GCGR) are emerging as a potential new class of important therapeutics in type 2 diabetes (T2D). Reliable and quantitative assessments of in vivo occupancy on each receptor would improve the understanding of the efficacy of this class of drugs. In this study we investigated the target occupancy of the dual agonist SAR425899 at the GLP1R in pancreas and GCGR in liver by Positron Emission Tomography/Computed Tomography (PET/CT).

Automated GMP-Compliant Production of [Ga]Ga-DO3A-Tuna-2 for PET Microdosing Studies of the Glucagon Receptor in Humans.

: [Ga]Ga-DO3A-VS-Cys-Tuna-2 (previously published as [Ga]Ga-DO3A-VS-Cys-S01-GCG) has shown high-affinity specific binding to the glucagon receptor (GCGR) in vitro and in vivo in rats and non-human primates in our previous studies, confirming the suitability of the tracer for drug development applications in humans. The manufacturing process of [Ga]Ga-DO3A-VS-Cys-Tuna-2 was automated for clinical use to meet the radiation safety and good manufacturing practice (GMP) requirements. The automated synthesis platform (Modular-Lab PharmTrace, Eckert & Ziegler, Eurotope, Germany), disposable cassettes for Ga-labeling, and pharmaceutical-grade Ge/Ga generator (GalliaPharm) used in the study were purchased from Eckert & Ziegler.

Assessment of glucagon receptor occupancy by Positron Emission Tomography in non-human primates.

The glucagon receptor (GCGR) is an emerging target in anti-diabetic therapy. Reliable biomarkers for in vivo activity on the GCGR, in the setting of dual glucagon-like peptide 1/glucagon (GLP-1/GCG) receptor agonism, are currently unavailable. Here, we investigated [Ga]Ga-DO3A-S01-GCG as a biomarker for GCGR occupancy in liver, the tissue with highest GCGR expression, in non-human primates (NHP) by PET.

Prognostic significance of P-wave morphology in patients with coronary artery disease.

Introduction: The prognostic significance of P-wave morphology in patients with coronary artery disease (CAD) is not well-known.

Methods: A total of 1946 patients with angiographically verified CAD were included in the Innovation to reduce Cardiovascular Complications of Diabetes at the Intersection (ARTEMIS) study. The P-wave morphology could be analyzed in 1797 patients.

First-in-class positron emission tomography tracer for the glucagon receptor.

Unlabelled: The glucagon receptor (GCGR) is emerging as an important target in anti-diabetic therapy, especially as part of the pharmacology of dual glucagon-like peptide-1/glucagon (GLP-1/GCG) receptor agonists. However, currently, there are no suitable biomarkers that reliably demonstrate GCG receptor target engagement.

Methods: Two potent GCG receptor peptide agonists, S01-GCG and S02-GCG, were labeled with positron emission tomography (PET) radionuclide gallium-68.

Distinct Pathogenesis of Pancreatic Cancer Microvesicle-Associated Venous Thrombosis Identifies New Antithrombotic Targets In Vivo.

Objective: Cancer patients are at high risk of developing deep venous thrombosis (DVT) and venous thromboembolism, a leading cause of mortality in this population. However, it is largely unclear how malignant tumors drive the prothrombotic cascade culminating in DVT.

Approach And Results: Here, we addressed the pathophysiology of malignant DVT compared with nonmalignant DVT and focused on the role of tumor microvesicles as potential targets to prevent cancer-associated DVT.

Transfusion and blood stream infections after coronary surgery.

The aim of this study was to evaluate the impact of blood transfusion on bloodstream infections. This study included 2764 patients who underwent isolated coronary artery bypass grafting. Blood cultures were drawn in 27.

Quality of life in patients with pancreatic ductal adenocarcinoma undergoing pancreaticoduodenectomy.

Introduction: Survival for pancreatic ductal adenocarcinoma (PDAC) is relatively short even after complete resection. Pancreaticoduodenectomy (PD) carries a high risk for postoperative morbidity, and the effect on quality of life (QoL) is unclear. We aimed to study QoL in PDAC patients undergoing PD.

Targeting PI3K/mTOR signaling exerts potent antitumor activity in pheochromocytoma in vivo.

Pheochromocytomas (PCCs) are mostly benign tumors, amenable to complete surgical resection. However, 10-17% of cases can become malignant, and once metastasized, there is no curative treatment for this disease. Given the need to identify the effective therapeutic approaches for PCC, we evaluated the antitumor potential of the dual-PI3K/mTOR inhibitor BEZ235 against these tumors.

Imaging the Cytokine Receptor CXCR4 in Atherosclerotic Plaques with the Radiotracer Ga-Pentixafor for PET.

Ga-pentixafor is a radiotracer for PET that binds with nanomolar affinity to CXCR4. The CXCR4 receptor is expressed at the surface of inflammatory cells. The objective of the study was to analyze the ability of radiolabeled pentixafor to detect CXCR4 expression on inflammatory cells present in atherosclerotic plaques of an experimental rabbit model.

Disulfide HMGB1 derived from platelets coordinates venous thrombosis in mice.

Deep venous thrombosis (DVT) is one of the most common cardiovascular diseases, but its pathophysiology remains incompletely understood. Although sterile inflammation has recently been shown to boost coagulation during DVT, the underlying molecular mechanisms are not fully resolved, which could potentially identify new anti-inflammatory approaches to prophylaxis and therapy of DVT. Using a mouse model of venous thrombosis induced by flow reduction in the vena cava inferior, we identified blood-derived high-mobility group box 1 protein (HMGB1), a prototypical mediator of sterile inflammation, to be a master regulator of the prothrombotic cascade involving platelets and myeloid leukocytes fostering occlusive DVT formation.

Immuno-PET Imaging of Engineered Human T Cells in Tumors.

Sensitive in vivo imaging technologies applicable to the clinical setting are still lacking for adoptive T-cell-based immunotherapies, an important gap to fill if mechanisms of tumor rejection or escape are to be understood. Here, we propose a highly sensitive imaging technology to track human TCR-transgenic T cells in vivo by directly targeting the murinized constant TCR beta domain (TCRmu) with a zirconium-89 ((89)Zr)-labeled anti-TCRmu-F(ab')2 fragment. Binding of the labeled or unlabeled F(ab')2 fragment did not impair functionality of transgenic T cells in vitro and in vivo Using a murine xenograft model of human myeloid sarcoma, we monitored by Immuno-PET imaging human central memory T cells (TCM), which were transgenic for a myeloid peroxidase (MPO)-specific TCR.