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Calcium phosphate bions (CPB) are biomimetic mineralo-organic nanoparticles which represent a physiological mechanism regulating the function, transport and disposal of calcium and phosphorus in the human body. We hypothesised that CPB may be pathogenic entities and even a cause of cardiovascular calcification. Here we revealed that CPB isolated from calcified atherosclerotic plaques and artificially synthesised CPB are morphologically and chemically indistinguishable entities. Their formation is accelerated along with the increase in calcium salts-phosphates/serum concentration ratio. Experiments in vitro and in vivo showed that pathogenic effects of CPB are defined by apoptosis-mediated endothelial toxicity but not by direct tissue calcification or functional changes in anti-calcification proteins. Since the factors underlying the formation of CPB and their pathogenic mechanism closely resemble those responsible for atherosclerosis development, further research in this direction may help us to uncover triggers of this disease.

Methane dehydroaromatization was studied over a series of impregnated Mo/ZSM-5 catalysts with different molybdenum contents and Si/Al atomic ratios in the parent H-ZSM-5 zeolites. The maximum catalytic activity (∼14% CH4 conversion) and benzene formation selectivity (∼70%) were observed for the samples with 2%−5% molybdenum. The activity and selectivity are improved when the Si/Al ratio is decreased from 45 to 17. After pretreatment in argon and reaction at 720 °C, the catalysts have been characterized by textural methods, X-ray diffractometry (XRD), differential thermal analysis (DTA), high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray spectroscopy (EDX). As determined by HRTEM, after the pretreatment, the MoO x phase is highly dispersed on the external surface of the zeolite. During the reaction, molybdenum carbide nanoparticles 2−15 nm in size are formed on the external surface, and the molybdenum-containing clusters are deposited in the zeolite channels. The carbonaceous deposits (CDs) are formed as graphite layers on the surface of Mo2C nanoparticles that were >2 nm in size, and as friable layers with a disordered structure on the external surface of the zeolite. According to EDX, XRD, and DTA studies, the content of the CD and the extent of their condensation (the C/H ratio) increase with the time-on-stream. For all the studied molybdenum contents (1%−10%) and time-on-stream values (0.5−6 h), the CDs formed on the catalysts with Si/Al = 17 are characterized by one maximum of the exothermic burn-out effect in DTA, whereas on the catalysts with Si/Al = 30 and 45, they are characterized by two such maxima. A correlation between the catalyst activity, the selectivity versus nanostructure, and the location of the molybdenum phases and CDs is discussed.