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One novel organic-inorganic hybrid supramolecular compound named Adeninium orthoperiodate (1−) bis(hydrate) (I) has been synthesized and characterized by FT-IR spectroscopy and single-crystal X-ray diffraction complemented with a quantum chemical study performed with DFT method at the B3LYP/3–21G level. The title compound crystallized in the monoclinic centrosymmetric P 21/n space group. In the molecular arrangement, the different entities are held together through the interplay of intermolecular O···H N/O and N H···O hydrogen bonds, that found to be effective in stabilizing the three-dimensional crystal packing. The hydrogen bonds network of (I) contains an interesting cyclic homosynthon of R 2 2 (10) graph set notation involving the adeninium Hoogsteen sites (N6—H1N···N7). The role of such interactions is known to be predominant in the stabilization of the usual 1H,9H tautomer. The different intermolecular interactions of (I) were quantified and analysed using Hirshfeld surface analysis, enrichment ratio (E) and fingerprint plots. The obtained results indicate that the main contributions are ascribed to O···H and H···H interactions. Scanning electron microscopy (SEM) was used to provide an extremely enlarged image of the sample morphology of (I), as well as information on its chemical composition using an energy dispersive X-ray spectrometer (EDS) detector, which confirms that the compound was successfully synthesized. The complementary theoretical achievements were found in a good agreement with respect to the experimental data. Moreover, a natural bond orbital (NBO) analysis was performed to evaluate the nature of bonding and the strength of the intra and inter-molecular interactions. Furthermore, the calculations of HOMO and LUMO energies were carried out to investigate the charge transfer within the molecular structure. The molecular electrostatic potential maps were used to detect the possible electrophilic and nucleophilic sites in (I).

International audience; Colorectal cancer (CRC) remains the most cancer type related to chronic inflammation; however, the mechanisms that link inflammation to CRC development and progression are still poorly understood. Our study aimed to investigate one of the prominent inflammatory response in cancers, iNOS/NO system. In this regard, we evaluated the link between the iNOS/NO system and CRC progression, its relation with the host immune responses and its response to cetuximab combined with chemotherapy. We found that the nitrite levels were nearly twice as high in metastatic CRC plasma and culture supernatants from PBMCs and tumor explants compared with those without metastases and healthy controls. Interestingly, we showed that the highest iNOS expression and NO levels are present in the damaged CRC tissues that have highest leukocyte infiltration. Our findings highlight the implication of iNOS/NO system in tissue alteration and leukocyte invasion. Thus, we observed imbalance between effector/memory T cell markers and Treg transcription factor (Foxp3). Accordingly, we detected higher IFNγ and T-bet expression levels in colorectal tumor tissues at early stage. In contrast, consistent with iNOS and Foxp3 expression, TGFβ, CTLA-4 and IL-10 were significantly related to the tumor stage progression. Furthermore, our study revealed that Cetuximab combined with chemotherapy treatment markedly down-regulates iNOS/NO system as well as IL-10 and TGFβ levels. Altogether, we conclude that cetuximab can potentiate the efficacy of chemotherapy, particularly by iNOS/NO system and immunosuppressive cytokines modulation. Thus, we suggest that iNOS/NO system may represent an attractive candidate biomarker for monitoring CRC progression, malignity and response to therapy.

International audience; A lattice Boltzmann method is developed to investigate a situation combining natural and forced convection for lid driven, in a two-dimensional square cavity over a much wider range of Rayleigh (Ra) and Reynolds (Re) numbers. The features of dynamic and thermal fields are presented for different Ra and Re to explain the role of Richardson number (Ri) in mixed convection. Effects on the flow and heat transfer are discussed in both cases of cooperating and opposing effects. Within the scope of this study, the predictive formulas are obtained to describe the heat transfer in terms of relationship between the average Nusselt number (Nu) and the controlling parameters. Different from the LBGK approximation, a moment LB model is applied in this work.

International audience; The present work deals with the hydraulic characterization of twophase flow with phase change in a channel filled with metallic foam. We provide a general presentation of metallic foams including morphological characteristics, fabrication processes and industrial applications. The experimental facility, which consists of a hydrodynamic loop, the test section, measurement devices, and the data acquisition system, is presented. The Metallic foam sample tested in the present work is manufactured by SCPS (French manufacturer). N-pentane is used as a coolant fluid. The mass velocity values lie between 4 and 49 kg/ m 2 s, while the heating power in the test section ranges from 0 to 35 W/cm 2. The effect of fluid acceleration on the pressure profiles is demonstrated in the convective boiling regime. The measured pressure profiles are used to locate the thermodynamic zones inside the test channel. Then, the evolution of the pressure drop versus mass velocity is established and compared to results obtained from the application of the homogeneous model to two-phase flow.