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Myocardial infarction causes 7.3 million deaths worldwide, mostly for fibrillation that electrically originates from the damaged areas of the left ventricle. Conventional cardiac bypass graft and percutaneous coronary interventions allow reperfusion of the downstream tissue but do not counteract the bioelectrical alteration originated from the infarct area. Genetic, cellular, and tissue engineering therapies are promising avenues but require days/months for permitting proper functional tissue regeneration. Here we engineered biocompatible silicon carbide semiconductive nanowires that synthetically couple, via membrane nanobridge formations, isolated beating cardiomyocytes over distance, restoring physiological cell-cell conductance, thereby permitting the synchronization of bioelectrical activity in otherwise uncoupled cells. Local in-situ multiple injections of nanowires in the left ventricular infarcted regions allow rapid reinstatement of impulse propagation across damaged areas and recover electrogram parameters and conduction velocity. Here we propose this nanomedical intervention as a strategy for reducing ventricular arrhythmia after acute myocardial infarction., (© 2022. The Author(s).)

Robust cell adhesion is known to be necessary to promote cell colonization of biomaterials and differentiation of progenitors. In this paper, we propose the functionalization of Silicon Oxycarbide (SiO x C y ) nanowires (NWs) with 3-mercaptopropyltrimethoxysilane (MPTMS), a molecule containing a terminal -SH group. The aim of this functionalization was to develop a surface capable to adsorb proteins and promote cell adhesion, proliferation and a better deposition of extracellular matrix. This functionalization can be used to anchor other structures such as nanoparticles, proteins or aptamers. It was observed that surface functionalization markedly affected the pattern of protein adsorption, as well as the in vitro proliferation of murine osteoblastic cells MC3T3-E1, which was increased on functionalized nanowires (MPTMS-NWs) compared to bare NWs (control) (p < 0.0001) after 48 h. The cells showed a better adhesion on MPTMS-NWs than on bare NWs, as confirmed by immunofluorescence studies on the cytoskeleton, which showed a more homogeneous vinculin distribution. Gene expression analysis showed higher expression levels for alkaline phosphatase and collagen I, putative markers of the osteoblast initial differentiation stage. These results suggest that functionalization of SiO x C y nanowires with MPTMS enhances cell growth and the expression of an osteoblastic phenotype, providing a promising strategy to improve the biocompatibility of SiO x C y nanowires for biomedical applications.

The chemistry of copper(I) with water-soluble phosphines is an emergent area of study which has the objective of finding ligands that stabilize copper in its lower oxidation state. Cu(I) has been found relevant in the mechanism of copper transports into cells, and the accessibility of this oxidation state has implications in oxidative stress processes. For these reasons the possibility to deal with stable, water soluble copper(I) is an attractive approach for devising new biologically relevant metal-based drugs and chelating agents. Here we present the X-ray absorption spectroscopy (XAS) and UV-visible spectrophotometric study of the [Cu(PTA) 4 ]BF 4 complex (PTA = aminophosphine‑1,3,5‑triaza‑7‑phosphaadamantane). In particular, we have studied the stability of the [Cu(PTA) n ] + species (n = 2-4) in aqueous medium, and their speciation as a function of the total [Cu(PTA) 4 ]BF 4 concentration by means of competitive UV-visible spectrophotometric titrations using metallochromic indicators. Also, the structure in solution of the Cu(I)/PTA species and the nature of the first coordination sphere of the metal were studied by transformed XAS. Both techniques allowed to study samples with total [Cu(PTA) 4 ]BF 4 concentration down to 68-74 μM, possibly relevant for biological applications. Overall, our data suggest that the [Cu(PTA) n ] + species are stable in solution, among which [Cu(PTA) 2 ] + has a remarkable thermodynamic stability. The tendency of this last complex to form adducts with N-donor ligands is demonstrated by the spectrophotometric data. The biological relevance of PTA towards Cu(I), especially in terms of chemotreatments and chelation therapy, is discussed on the basis of the speciation model the Cu(I)/PTA system., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The paramagnetic one-dimensional 1 H NMR spectra of twelve Ln III Na I (OAc) 4 [12-MC Mn III (N)shi -4] complexes, where Ln III is Pr III -Yb III (except Pm III ) and Y III , are reported. Their solid-state isostructural nature is confirmed in methanol-d 4 solution, as a similar pattern in the 1 H NMR spectra is observed along the series. Notably, a relatively well-resolved spectrum is reported for the Gd III complex. The chemical shift data are analyzed using the "all lanthanides" method, and the Fermi contact and pseudo-contact contributions are calculated for the lanthanide-induced shift (LIS). For the Tb III -Yb III complexes, the pseudo-contact contributions are typically 1 order of magnitude higher than the Fermi contact contributions; however, for the Gd III complex, the Fermi contact is the main contribution to the paramagnetic chemical shift. For the methyl protons of the axial acetate ( - OAc) ligands, the LIS is opposite in sign, with respect to that of the aromatic salicylhydroximate (shi 3- ) protons, because of structural rearrangements that occur upon dissociation of the Na I cation in solution. The calculated crystal field parameters (B Ln ) for the Tb III (360 cm -1 ), Dy III (250 cm -1 ), Ho III (380 cm -1 ), Er III (410 cm -1 ), Tm III (620 cm -1 ), and Yb III (380 cm -1 ) complexes are not constant, likely as a consequence of the inaccuracy of the Bleaney's constants and, to a smaller extent, the small structural changes that occur in solution. Overall, the metallacrown scaffold retains structural integrity and similarity in solution for the entire series; however, small structural features, which do not affect the overall similarity, do likely occur.