High-Resolution Free-Breathing Chemical-Shift-Encoded MRI for Characterizing Lymph Nodes in the Upper Abdomen.

Objectives: Accurate lymph node (LN) staging is crucial for managing upper abdominal cancers. Ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging effectively distinguishes healthy and metastatic LNs through fat/water and -weighted imaging. However, respiratory motion artifacts complicate detection of abdominal LNs.

Utilizing MRI, [F]FDG-PET and [Zr]Zr-DFO-28H1 FAP-PET tracer to assess inflammation and fibrogenesis in a reproducible lung injury rat model: a multimodal imaging study.

Objective: Accurate imaging biomarkers that indicate disease progression at an early stage are highly important to enable timely mitigation of symptoms in progressive lung disease. In this context, reproducible experimental models and readouts are key. Here, we aim to show reproducibility of a lung injury rat model by inducing disease and assessing disease progression by multi-modal non-invasive imaging techniques at two different research sites.

The Potential of Iron Oxide Nanoparticle-Enhanced MRI at 7 T Compared With 3 T for Detecting Small Suspicious Lymph Nodes in Patients With Prostate Cancer.

Background: Accurate detection of lymph node (LN) metastases in prostate cancer (PCa) is a challenging but crucial step for disease staging. Ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI) enables distinction between healthy LNs and nodes suspicious for harboring metastases. When combined with MRI at an ultra-high magnetic field, an unprecedented spatial resolution can be exploited to visualize these LNs.

Estimating foraging behavior in rodents using a modified paradigm measuring threat imminence dynamics.

Animals need to respond to threats to avoid danger and approach rewards. In nature, these responses did not evolve alone but are always accompanied by motivational conflict. A semi-naturalistic threat imminence continuum model models the approach-avoidance conflict and is able to integrate multiple behaviors into a single paradigm.

Subnodal Correspondence of PSMA Expression and USPIO-MRI in Metastatic Pelvic Lymph Nodes in Prostate Cancer.

Objectives: Two advanced imaging modalities used to detect lymph node (LN) metastases in prostate cancer patients are prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography and ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI). As these modalities use different targets, a subnodal comparison is needed to interpret both their correspondence and their differences. The aim of this explorative study was to compare ex vivo 111 In-PSMA μSPECT images with high-resolution 7 T USPIO μMR images and histopathology of resected LN specimens from prostate cancer patients to assess the degree of correspondence at subnodal level.

Perinatal exposure to the immune-suppressant di-n-octyltin dichloride affects brain development in rats.

Disruption of the immune system during embryonic brain development by environmental chemicals was proposed as a possible cause of neurodevelopmental disorders. We previously found adverse effects of di-n-octyltin dichloride (DOTC) on maternal and developing immune systems of rats in an extended one-generation reproductive toxicity study according to the OECD 443 test guideline. We hypothesize that the DOTC-induced changes in the immune system can affect neurodevelopment.

Glucose versus fructose metabolism in the liver measured with deuterium metabolic imaging.

Chronic intake of high amounts of fructose has been linked to the development of metabolic disorders, which has been attributed to the almost complete clearance of fructose by the liver. However, direct measurement of hepatic fructose uptake is complicated by the fact that the portal vein is difficult to access. Here we present a new, non-invasive method to measure hepatic fructose uptake and metabolism with the use of deuterium metabolic imaging (DMI) upon administration of [6,6'-H]fructose.

Imatinib attenuates reperfusion injury in a rat model of acute myocardial infarction.

Following an acute myocardial infarction, reperfusion of an occluded coronary artery is often accompanied by microvascular injury, leading to worse long-term prognosis. Experimental studies have revealed the potential of tyrosine-kinase inhibitor imatinib to reduce vascular leakage in various organs. Here, we examined the potential of imatinib to attenuate microvascular injury in a rat model of myocardial reperfusion injury.

Mechanical high-intensity focused ultrasound creates unique tumor debris enhancing dendritic cell-induced T cell activation.

Introduction: tumor ablation releases a unique repertoire of antigens from a heterogeneous population of tumor cells. High-intensity focused ultrasound (HIFU) is a completely noninvasive ablation therapy that can be used to ablate tumors either by heating (thermal (T)-HIFU) or by mechanical disruption (mechanical (M)-HIFU). How different HIFU ablation techniques compare with respect to their antigen release profile, their activation of responder T cells, and their ability to synergize with immune stimuli remains to be elucidated.

Validation of In Vivo Nodal Assessment of Solid Malignancies with USPIO-Enhanced MRI: A Workflow Protocol.

Background: In various cancer types, the first step towards extended metastatic disease is the presence of lymph node metastases. Imaging methods with sufficient diagnostic accuracy are required to personalize treatment. Lymph node metastases can be detected with ultrasmall superparamagnetic iron oxide (USPIO)-enhanced magnetic resonance imaging (MRI), but this method needs validation.

In Vivo PET Imaging of Monocytes Labeled with [Zr]Zr-PLGA-NH Nanoparticles in Tumor and Infection Models.

The exponential growth of research on cell-based therapy is in major need of reliable and sensitive tracking of a small number of therapeutic cells to improve our understanding of the in vivo cell-targeting properties. In-labeled poly(lactic--glycolic acid) with a primary amine endcap nanoparticles ([In]In-PLGA-NH NPs) were previously used for cell labeling and in vivo tracking, using SPECT/CT imaging. However, to detect a low number of cells, a higher sensitivity of PET is preferred.

F MRI Imaging Strategies to Reduce Isoflurane Artifacts in In Vivo Images.

Purpose: Isoflurane (ISO) is the most commonly used preclinical inhalation anesthetic. This is a problem in F MRI of fluorine contrast agents, as ISO signals cause artifacts that interfere with unambiguous image interpretation and quantification; the two most attractive properties of heteronuclear MRI. We aimed to avoid these artifacts using MRI strategies that can be applied by any pre-clinical researcher.

Simultaneous Recording of the Uptake and Conversion of Glucose and Choline in Tumors by Deuterium Metabolic Imaging.

Increased glucose and choline uptake are hallmarks of cancer. We investigated whether the uptake and conversion of [H]choline alone and together with that of [6,6'-H]glucose can be assessed in tumors via deuterium metabolic imaging (DMI) after administering these compounds. Therefore, tumors with human renal carcinoma cells were grown subcutaneously in mice.

Partial Adrenalectomy Carries a Considerable Risk of Incomplete Cure in Primary Aldosteronism.

Purpose: Laparoscopic adrenalectomy is standard treatment for patients with unilateral aldosterone-producing adenomas, but surgeons are increasingly tempted to perform partial adrenalectomy, disregarding potential multinodularity of the adrenal. We assess the diagnostic value of endoscopic ultrasound for differentiating solitary adenomas from multinodularity by examining in-depth adrenal pathology with ex vivo 11.7 T magnetic resonance imaging and immunohistochemistry.

Novel Fluorinated Poly (Lactic-Co-Glycolic acid) (PLGA) and Polyethylene Glycol (PEG) Nanoparticles for Monitoring and Imaging in Osteoarthritis.

Polymeric nanoparticles (NPs) find many uses in nanomedicine, from drug delivery to imaging. In this regard, poly (lactic-co-glycolic acid) (PLGA) and polyethylene glycol (PEG) particles are the most widely applied types of nano-systems due to their biocompatibility and biodegradability. Here we developed novel fluorinated polymeric NPs as vectors for multi-modal nanoprobes.

In vivo clearance of F MRI imaging nanocarriers is strongly influenced by nanoparticle ultrastructure.

Perfluorocarbons hold great promise both as imaging agents, particularly for F MRI, and in therapy, such as oxygen delivery. F MRI is unique in its ability to unambiguously track and quantify a tracer while maintaining anatomic context, and without the use of ionizing radiation. This is particularly well-suited for inflammation imaging and quantitative cell tracking.

Pyruvate-lactate exchange and glucose uptake in human prostate cancer cell models. A study in xenografts and suspensions by hyperpolarized [1- C]pyruvate MRS and [ F]FDG-PET.

Reprogramming of energy metabolism in the development of prostate cancer can be exploited for a better diagnosis and treatment of the disease. The goal of this study was to determine whether differences in glucose and pyruvate metabolism of human prostate cancer cells with dissimilar aggressivenesses can be detected using hyperpolarized [1- C]pyruvate MRS and [ F]FDG-PET imaging, and to evaluate whether these measures correlate. For this purpose, we compared murine xenografts of human prostate cancer LNCaP cells with those of more aggressive PC3 cells.

Imaging Hyperpolarized Pyruvate and Lactate after Blood-Brain Barrier Disruption with Focused Ultrasound.

Imaging of hyperpolarized C-labeled substrates has emerged as an important magnetic resonance (MR) technique to study metabolic pathways in real time in vivo. Even though this technique has found its way to clinical trials, in vivo dynamic nuclear polarization is still mostly applied in preclinical models. Its tremendous increase in signal-to-noise ratio (SNR) overcomes the intrinsically low MR sensitivity of the C nucleus and allows real-time metabolic imaging in small structures like the mouse brain.

MRI evaluation of vulvar squamous-cell carcinoma in fresh radical local excision specimens for cancer localization and prediction of surgical tumor-free margins.

In the surgical treatment of vulvar squamous-cell carcinoma (VSCC), tumor-free margins of 8 mm or more are considered adequate. However, limited perioperative information on the tumor-free margins other than the surgeon's own estimation is available. The purpose of this study was therefore to investigate the feasibility of ex vivo MRI in localizing VSCC and to assess the surgical tumor-free margins in fresh radical local excision (RLE) specimens to guide the surgeon during resections.

MRI as a tool to assess surgical margins and pseudocapsule features directly following partial nephrectomy for small renal masses.

Purpose: To evaluate the feasibility of ex vivo 7T MRI to assess surgical margins (SMs) and pseudocapsule (PC) features after partial nephrectomy (PN).

Materials And Methods: In this prospective, IRB-approved study, seven patients undergoing a PN for nine tumours between November 2014 and July 2015 were included for analysis after obtaining informed consent. MRI of the specimen was acquired using a 7T small bore scanner.