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8-Quinolinecarboxaldehyde selenosemicarbazone (H8qasesc) and its octahedral Co(III) complex were characterized by single crystal X-ray diffraction analysis, spectroscopy methods and cyclic voltammetry. The antineoplastic activity of the ligand and the complex has been assessed on an acute monocytic leukemia cell line (THP-1) and AsPC-1 cancer stem cell (CSC) line derived from a patient suffering from pancreatic adenocarcinoma, with cisplatin (CDDP) as a reference compound. Evaluation involved determination of pro-apoptotic activity, changes in cell cycle distribution, the role of caspase activation in the process of cell death, and the ability of the investigated compounds to challenge reprogramming of the CSC phenotype. Compared to CDDP, treatment with H8qasesc induced a higher apoptotic response in both investigated cell lines. Apoptosis triggered by H8qasesc was highly caspase-dependent but did not include activation of either caspase-8 or -9. According to cell cycle changes H8qasesc delayed the transition of cells during DNA replication but in a manner different from that of CDDP. The ligand did not show nuclease activity on pUC19 plasmid, while docking studies disclosed that it does not have intercalating properties. Treatment of THP-1 cells with the Co(III) complex resulted in a strong toxic response, whereas cell death in the treated AsPC-1 line was not achieved for 24 h. Additionally, the complex concentration-dependently digested plasmid DNA which might be the cause of its cytotoxic activity. Finally, H8qasesc successfully initiated reprogramming of the CSC phenotype in the AsPC-1 cell line. This is peer-reviewed version of the following article: Filipović, N. R.; Bjelogrlić, S.; Portalone, G.; Pelliccia, S.; Silvestri, R.; Klisurić, O.; Senćanski, M.; Stanković, D.; Todorović, T. R.; Muller, C. D. Pro-Apoptotic and pro-Differentiation Induction by 8-Quinolinecarboxaldehyde Selenosemicarbazone and Its Co(III) Complex in Human Cancer Cell Lines. MedChemComm 2016, 7 (8), 1604–1616. [https://doi.org/10.1039/c6md00199h] Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3599]

International audience; The versatile coordination behavior of 4(N, N')-diethylaminosalicylaldehyde-4(N)-substituted thiosemicarbazones (H2L1-4) was examined in 1 : 1 stoichiometric reactions with [PdCl2(AsPh3)(2)]. All the new complexes (1-4) were characterized by analytical, IR, absorption and H-1 NMR spectroscopic studies. The complexes [Pd(DeaSal-tsc)(AsPh3)] (1), [Pd(H-DeaSal-mtsc)(AsPh3)] (2) and [Pd(H-DeaSal-etsc)(AsPh3)] (3) were structurally characterized by single crystal X-ray diffraction studies. Crystallographic results showed that the ligand H2L1 is coordinated as mono negative tridentate ONS donor ligand in the complex 1 by forming six and five member rings. Whereas, the ligands H2L2 and H2L3 bound to palladium in 2 and 3 as mono negative bidentate NS donor by forming a five member chelate ring by leaving the third potential donor atom, phenolic oxygen remain intact without being participated in bonding. The non-participation of the phenolic oxygen may be due to the intra molecular hydrogen bonding between phenolic hydrogen and N2 nitrogen. The interaction of the palladium(II) precursor [PdCl2(AsPh3)(2)], ligands ((H2L1-H2L4)) and their corresponding complexes (1-4) with calf-thymus DNA (CT DNA) has been explored by absorption and emission titration methods. Based on the observations, an intercalative binding mode of DNA has been proposed. The protein binding abilities of the new complexes along with their precursor were monitored by quenching of tryptophan and tyrosine residues using BSA as model protein. From the studies, it was found that the new palladium metallacycles exhibited better affinity than their precursors.

This paper deals with the simulation of microbial degradation of organic matter in soil within the pore space at a microscopic scale. Pore space was analysed with micro-computed tomography and described using a sphere network coming from a geometrical modelling algorithm. The biological model was improved regarding previous work in order to include the transformation of dissolved organic compounds and diffusion processes. We tested our model using experimental results of a simple substrate decomposition experiment (fructose) within a simple medium (sand) in the presence of different bacterial strains. Separate incubations were carried out in microcosms using five different bacterial communities at two different water potentials of −10 and −100 cm of water. We calibrated the biological parameters by means of experimental data obtained at high water content, and we tested the model without changing any parameters at low water content. Same as for the experimental data, our simulation results showed that the decrease in water content caused a decrease of mineralization rate. The model was able to simulate the decrease of connectivity between substrate and microorganism due the decrease of water content.

International audience; Antimicrobial N-halamine polymers and coatings have been studied extensively over the past decade thanks to their numerous qualities such as effectiveness toward a broad spectrum of microorganisms, long-term stability, regenerability, safety to humans and environment and low cost. In this review, recent developments are described by emphasizing the synthesis of polymers and/or coatings having N-halamine moieties. Actually, three main approaches of preparation are given in detail: polymerization, generation by electrochemical route with proteins as monomers and grafting with precursor monomers. Identification and characterization of the formation of the N-halamine bonds (>N-X with X = Cl or Br or I) by physical techniques such as Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR), energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and by chemical reactions are described. In order to check the antimicrobial activity of the N-halamine compounds, bacterial tests are also described. Finally, some examples of application of these N-halamines in the water treatment, paints, healthcare equipment, and textile industries are presented and discussed.

International audience; We report the synthesis and resolution of a series of new chiral "3 + 1" oxorhenium(V) complexes, designed for high-resolution laser spectroscopy experiments probing molecular parity-violation (PV) effects in the Re=O stretching mode frequency. These complexes display a particularly simple chemical structure, with the rhenium atom as the stereogenic center, and show large PV energy differences according to our calculations. They were obtained in the racemic and enantioenriched forms, in the latter case by using either semi-preparative chiral HPLC resolution or enantioselective synthesis. The vibrational transition frequency differences between the enantiomeric pairs due to PV have been calculated with two- and four-component relativistic Hamiltonians using Hartree-Fock (HF) and density functional theory (DFT). For three complexes, including one synthesized in enantioenriched form, our HF calculations predict frequency differences above the present resolution limit of 1 Hz. These results confirm the order of magnitude for the calculated HF PV vibrational frequency differences reported earlier for this class of compounds [P. Schwerdtfeger and R. Bast, J. Am. Chem. Soc., 2004, 126, 1652]. However, at the DFT level the PV vibrational frequency differences are in some cases reduced by an order of magnitude, but are still within the sensitivity of 0.01 Hz, which is the anticipated sensitivity in a new proposed experiment. We therefore believe that the present study represents an important step towards the experimental observation of PV in molecular systems, and emphasizes the extreme sensitivity of the PV vibrational frequency difference to the chemical environment around the rhenium center.