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Vitamin D plays a crucial role in modulating the innate immune response by interacting with its intracellular receptor, VDR. In this review, we address vitamin D/VDR signaling and how it contributes to the regulation of intestinal and respiratory microbiota. We additionally review some components of the innate immune system, such as the barrier function of the pulmonary and intestinal epithelial membranes and secretion of mucus, with their respective modulation by vitamin D. We also explore the mechanisms by which this vitamin D/VDR signaling mounts an antimicrobial response through the transduction of microbial signals and the production of antimicrobial peptides that constitute one of the body’s first lines of defense against pathogens. Additionally, we highlight the role of vitamin D in clinical diseases, namely inflammatory bowel disease and acute respiratory distress syndrome, where excessive inflammatory responses and dysbiosis are hallmarks. Increasing evidence suggests that vitamin D supplementation may have potentially beneficial effects on those diseases.

For the first time, n-octane was tested as a swelling agent for the synthesis of a mesocellular silica foam (MCF(O)) and the latter was used as a Ni support for the dry reforming of methane reaction (DRM). Using n-Octane led to a MCF(O) material with smaller cells size (14 nm) than in conventional MCF(T) prepared in the presence of 1,3,5 trimethylbenzene (21 nm). Nickel precursor addition was done either by post-synthesis impregnation on preformed silica (incipient wetness impregnation (IWI), “two-solvents” (TS)) or during the synthesis of MCF (Direct synthesis, DS). All prepared materials were characterized in their calcined and reduced forms using N2 sorption, X-Ray Diffraction (XRD), Transmission Electronic Microscopy (TEM), Temperature Programmed Reduction (TPR) and X-Ray Fluorescence (XRF). A highly dispersed Ni0 active phase, mainly located in the MCF walls, as well as strong Ni-support interaction were emphasized for Ni-MCF(O)-DS. The catalytic performances of all the samples were investigated in DRM between 200 and 770 °C, then for 4 h (stability test) at 650 °C, using a Gas Hourly Space Velocity (GHSV) of 36 L g−1 h−1 and an equimolar ratio of CH4 and CO2 reactants. The Ni-MCF(O)-TS catalyst prepared by means of the “two-solvents” impregnation exhibited the highest CH4 and CO2 conversions. Compared to Ni-MCF(T), better performances were obtained with Ni-MCF(O) solids.