A Multicenter Preclinical MRI Study: Definition of Rat Brain Relaxometry Reference Maps.

Similarly to human population imaging, there are several well-founded motivations for animal population imaging, the most notable being the improvement of the validity of statistical results by pooling a sufficient number of animal data provided by different imaging centers. In this paper, we demonstrate the feasibility of such a multicenter animal study, sharing raw data from forty rats and processing pipelines between four imaging centers. As specific use case, we focused on T1 and T2 mapping of the healthy rat brain at 7T.

A pancreatic tumor-specific biomarker characterized in humans and mice as an immunogenic onco-glycoprotein is efficient in dendritic cell vaccination.

Oncofetal fucose-rich glycovariants of the pathological bile salt-dependent lipase (pBSDL) appear during human pancreatic oncogenesis and are detected by themonoclonal antibody J28 (mAbJ28). We aimed to identify murine counterparts onpancreatic ductal adenocarcinoma (PDAC) cells and tissue and investigate the potential of dendritic cells (DC) loaded with this unique pancreatic tumor antigen to promote immunotherapy in preclinical trials. Pathological BSDLs purified from pancreatic juices of patients with PDAC were cleaved to generate glycosylated C-terminal moieties (C-ter) containing mAbJ28-reactive glycoepitopes.

Rapid-Steady-State-T1 signal modeling during contrast agent extravasation: toward tumor blood volume quantification without requiring the arterial input function.

Purpose: This study demonstrates how to quantify the tumor blood volume fraction (BVf) using the dynamic Rapid-Steady-State-T1 (RSST1 )-MRI method despite contrast agent (CA) leakage and without arterial input function (AIF) determination.

Methods: For vasculature impermeable to CAs, the BVf is directly quantified from the RSST1 signal amplitude. In case of CA extravasation, we propose a two-compartment model to describe the dynamic RSST1 signal increase.

Quantitative rapid steady state T1 magnetic resonance imaging for cerebral blood volume mapping in mice: Lengthened measurement time window with intraperitoneal Gd-DOTA injection.

This work demonstrates how the rapid steady state T1 MRI technique for cerebral blood volume fraction (BVf) quantification can be used with intraperitoneal Gd-DOTA injections in mice at 4.7 T. The peak signal amplitude after intravenous administration (0.

How stereological analysis of vascular morphology can quantify the blood volume fraction as a marker for tumor vasculature: comparison with magnetic resonance imaging.

To assess angiogenesis noninvasively in a C6 rat brain tumor model, the rapid-steady-state-T(1) (RSST(1)) magnetic resonance imaging (MRI) method was used for microvascular blood volume fraction (BVf) quantification with a novel contrast agent gadolinium per (3,6 anhydro) α-cyclodextrin (Gd-ACX). In brain tissue contralateral to the tumor, equal BVfs were obtained with Gd-ACX and the clinically approved gadoterate meglumine (Gd-DOTA). Contrary to Gd-DOTA, which leaks out of the tumor vasculature, Gd-ACX was shown to remain vascular in the tumor tissue allowing quantification of the tumor BVf.

Increased anatomical detail by in vitro MR microscopy with a modified Golgi impregnation method.

Golgi impregnation is unique in its ability to display the dendritic trees and axons of large numbers of individual neurons by histology. Here we apply magnetic resonance microscopy to visualize the neuroanatomy of animal models by combining histologic fixation chemistry with paramagnetic contrast agents. Although there is some differential uptake of the standard small-molecular-weight contrast agents by different tissue types, detailed discrimination of tissue architecture in MR images does not approach that of standard histology.

A new Magnetic Resonance Imaging method for mapping the cerebral blood volume fraction: the rapid steady-state T1 method.

This paper describes a new rapid steady-state T(1) (RSST(1)) method for mapping the cerebral blood volume fraction (CBVf) by magnetic resonance imaging (MRI). The principle is based on a two-compartment model of the brain (intra- and extravascular), and the effects of paramagnetic contrast agents on the intravascular longitudinal relaxation time T(1). Using appropriate parameters, an Inversion-Recovery-Fast-Low-Angle-Shot sequence acts like a low pass T(1) filter, suppressing signals from tissues with T(1)>>TR (TR=repetition time).