In this article, we delve into the intricate behavior of electronic mechanisms underlying NMR magnetic shieldings, σ, in molecules containing heavy atoms such as cadmium, platinum, and mercury. Specifically, we explore PtXn^{−2} (X = F, Cl, Br, I; n = 4, 6) and XCl2 Te2 Y2 H6 (X = Cd, Hg; Y = N, P) molecular systems. It is known that the leading electronic mechanisms responsible for the relativistic effects on σ are well characterized by the linear response with elimination of small components model (LRESC). In this study, we present results obtained from the innovative LRESC-Loc model, which offers the same outcomes as the LRESC model but employs localized molecular orbitals (LMOs) instead of canonical MOs. These LMOs provide a chemist’s representation of atomic core, lone pairs, and bonds. The whole set of electronic mechanisms responsible of the relativistic effects can be expressed in terms of both non-ligand-dependent and ligand-dependent contributions. We elucidate the electronic origins of trends and behaviors exhibited by these di- verse mechanisms in the aforementioned molecular systems. In PtX4^{−2} molecules, the predominant relativistic mechanism is the well-established one-body spin-orbit (σ^SO(1) ) mechanism, while the paramagnetic mass-velocity (σ^Mv ) and Darwin (σ^Dw ) contributing mechanisms also demand con- sideration. However, in PtX6−2 molecules, the σ Mv+ Dw contribution surpasses that of the SO(1) mechanism, thus influencing the overall ligand-dependent contributions. As for complexes con- taining Cd and Hg, the ligand-dependent contributions exhibit similar magnitudes when nitrogen is substituted with phosphorus. The only discrepancy arises from the σ^SO(1) contribution, which changes sign between the two molecules due to the contribution of bond orbitals between the metal and tellurium atoms.

Anti-CD19 chimeric antigen receptor (CAR) T-cells represent a novel immunotherapy that has shown remarkable success in the treatment of adult relapsed or refractory (R/R) B-cell non-Hodgkin's lymphoma, adult R/R mantle cell lymphoma, and R/R acute paediatric lymphoblastic leukaemia. One barrier to the widespread use of CAR T-cell therapy is toxicity, primarily cytokine release syndrome (CRS) with a variable grade of severity. The main manifestations of CRS are fever, hypotension, cytopenia, organ dysfunction among others. Neurological toxicities vary widely and range from headaches to encephalopathy. In addition, anti-CD19 CAR T-cell therapy provokes an array of less frequent events, such as coagulopathies, delayed cytopenia, and cardiovascular toxicities. In general, toxicities are usually reversible and resolve on their own in most cases, though severe cases may require intensive care and immunosuppressive therapy. Deaths due to CRS, neurologic toxicity and infectious complications have been reported, which highlights the gravity of these syndromes and the critical nature of appropriate intervention. In this paper, we look at all available FDA- and EMA-approved information about the pathophysiology, clinical manifestations, risk factor reviews of existing toxicity grading systems, current management strategies, and guidelines for anti-CD19 CAR T-cell toxicities. We also present new approaches, which are under investigation, to mitigate these adverse events.