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The feasibility of ultrafast (1.7 s) ventilation MRI with a 1 × 1 × 50 mm³voxel size is demonstrated using hyperpolarized propane gas contrast agent in excised rabbit lungs on a 0.35 T clinical MRI scanner without any scanner modification. 

15 N spin–lattice relaxation dynamics in metronidazole- 15 N 3 and metronidazole- 15 N 2 isotopologues are studied for rational design of 15 N-enriched biomolecules for signal amplification by reversible exchange in microtesla fields. 15 N relaxation dynamics mapping reveals the deleterious effects of interactions with the polarization transfer catalyst and a quadrupolar 14 N nucleus within the spin-relayed 15 N– 15 N network. 

Abstract Background The mechanism by which immune cells regulate metastasis is unclear. Understanding the role of immune cells in metastasis will guide the development of treatments improving patient survival. Methods We used syngeneic orthotopic mouse tumour models (wild-type, NOD/scid and Nude), employed knockout ( CD8 and CD4 ) models and administered CXCL4. Tumours and lungs were analysed for cancer cells by bioluminescence, and circulating tumour cells were isolated from blood. Immunohistochemistry on the mouse tumours was performed to confirm cell type, and on a tissue microarray with 180 TNBCs for human relevance. TCGA data from over 10,000 patients were analysed as well. Results We reveal that intratumoral immune infiltration differs between metastatic and non-metastatic tumours. The non-metastatic tumours harbour high levels of CD8 + T cells and low levels of platelets, which is reverse in metastatic tumours. During tumour progression, platelets and CXCL4 induce differentiation of monocytes into myeloid-derived suppressor cells (MDSCs), which inhibit CD8 + T-cell function. TCGA pan-cancer data confirmed that CD8 low Platelet high patients have a significantly lower survival probability compared to CD8 high Platelet low . Conclusions CD8 + T cells inhibit metastasis. When the balance between CD8 + T cells and platelets is disrupted, platelets produce CXCL4, which induces MDSCs thereby inhibiting the CD8 + T-cell function. 

Abstract Nimorazole belongs to the imidazole‐based family of antibiotics to fight against anaerobic bacteria. Moreover, nimorazole is now in Phase 3 clinical trial in Europe for potential use as a hypoxia radiosensitizer for treatment of head and neck cancers. We envision the use of [¹⁵N₃]nimorazole as a theragnostic hypoxia contrast agent that can be potentially deployed in the next‐generation MRI‐LINAC systems. Herein, we report the first steps to create long‐lasting (for tens of minutes) hyperpolarized state on three¹⁵N sites of [¹⁵N₃]nimorazole with T₁of up to ca. 6 minutes. The nuclear spin polarization was boosted by ca. 67000‐fold at 1.4 T (corresponding toP_15Nof 3.2 %) by¹⁵N−¹⁵N spin‐relayed SABRE‐SHEATH hyperpolarization technique, relying on simultaneous exchange of [¹⁵N₃]nimorazole and parahydrogen on polarization transfer Ir‐IMes catalyst. The presented results pave the way to efficient spin‐relayed SABRE‐SHEATH hyperpolarization of a wide range of imidazole‐based antibiotics and chemotherapeutics.