Filter-exchange spectroscopy is sensitive to gradual cell membrane degradation.

Transmembrane water permeability changes occur after initialization of necrosis and are a mechanism for early detection of cell death. Filter-exchange spectroscopy (FEXSY) is sensitive to transmembrane water permeability and enables its quantification by magnetic resonance via the apparent exchange rate (AXR). In this study, we investigate AXR changes during necrotic cell death.

Novel Tumor Organoid-Based Mouse Model to Study Image Guided Radiation Therapy of Rectal Cancer After Noninvasive and Precise Endoscopic Implantation.

Purpose: Preoperative (neoadjuvant) radiation therapy (RT) is an essential part of multimodal rectal cancer therapy. Recently, total neoadjuvant therapy (TNT), which combines simultaneous radiochemotherapy with additional courses of chemotherapy, has emerged as an effective approach. TNT achieves a pathologic complete remission in approximately 30% of resected patients, opening avenues for treatment strategies that avoid radical organ resection.

Parahydrogen-Polarized [1- C]Pyruvate for Reliable and Fast Preclinical Metabolic Magnetic Resonance Imaging.

Hyperpolarization techniques increase nuclear spin polarization by more than four orders of magnitude, enabling metabolic MRI. Even though hyperpolarization has shown clear value in clinical studies, the complexity, cost and slowness of current equipment limits its widespread use. Here, a polarization procedure of [1- C]pyruvate based on parahydrogen-induced polarization by side-arm hydrogenation (PHIP-SAH) in an automated polarizer is demonstrated.

Repeatability and reproducibility of apparent exchange rate measurements in yeast cell phantoms using filter-exchange imaging.

Objectives: Development of a protocol for validation and quality assurance of filter-exchange imaging (FEXI) pulse sequences with well-defined and reproducible phantoms.

Materials And Methods: A FEXI pulse sequence was implemented on a 7 T preclinical MRI scanner. Six experiments in three different test categories were established for sequence validation, demonstration of the reproducibility of phantoms and the measurement of induced changes in the apparent exchange rate (AXR).

Spectrally selective bSSFP using off-resonant RF excitations permits high spatiotemporal resolution 3D metabolic imaging of hyperpolarized [1- C]Pyruvate-to-[1- C]lactate conversion.

Purpose: To develop a high spatiotemporal resolution 3D dynamic pulse sequence for preclinical imaging of hyperpolarized [1- C]pyruvate-to-[1- C]lactate metabolism at 7T.

Methods: A standard 3D balanced SSFP (bSSFP) sequence was modified to enable alternating-frequency excitations. RF pulses with 2.