Magnetic shielding accelerates the proliferation of human neuroblastoma cell by promoting G1-phase progression

Organisms have been exposed to the geomagnetic field (GMF) throughout evolutionary history. Exposure to the hypomagnetic field (HMF) by deep magnetic shielding has recently been suggested to have a negative effect on the structure and function of the central nervous system, particularly during early development. Although changes in cell growth and differentiation have been observed in the HMF, the effects of the HMF on cell cycle progression still remain unclear. Here we show that continuous HMF exposure significantly increases the proliferation of human neuroblastoma (SH-SY5Y) cells. The acceleration of proliferation results from a forward shift of the cell cycle in G1-phase. The G2/M-phase progression is not affected in the HMF. Our data is the first to demonstrate that the HMF can stimulate the proliferation of SH-SY5Y cells by promoting cell cycle progression in the G1-phase. This provides a novel way to study the mechanism of cells in response to changes of environmental magnetic field including the GMF

Monodisperse Metal Nanoparticle Catalysts: Synthesis, Characterizations, and Molecular Studies Under Reaction Conditions

We aim to develop novel catalysts that exhibit high activity, selectivity and stability under real catalytic conditions. In the recent decades, the fast development of nanoscience and nanotechnology has allowed synthesis of nanoparticles with well-defined size, shape and composition using colloidal methods. Utilization of mesoporous oxide supports effectively prevents the nanoparticles from aggregating at high temperatures and high pressures. Nanoparticles of less than 2 nm sizes were found to show unique activity and selectivity during reactions, which was due to the special surface electronic structure and atomic arrangements that are present at small particle surfaces. While oxide support materials are employed to stabilize metal nanoparticles under working conditions, the supports are also known to strongly interact with the metals through encapsulation, adsorbate spillover, and charge transfer. These factors change the catalytic performance of the metal catalysts as well as the conductivity of oxides. The employment of new in situ techniques, mainly high-pressure scanning tunneling microscopy (HPSTM) and ambient-pressure X-ray photoelectron spectroscopy (APXPS) allows the determination of the surface structure and chemical states under reaction conditions. HPSTM has identified the importance of both adsorbate mobility to catalytic turnovers and the metal substrate reconstruction driven by gaseous reactants such as CO and O-2. APXPS is able to monitor both reacting species at catalyst surfaces and the oxidation state of the catalyst while it is being exposed to gases. The surface composition of bimetallic nanoparticles depends on whether the catalysts are under oxidizing or reducing conditions, which is further correlated with the catalysis by the bimetallic catalytic systems. The product selectivity in multipath reactions correlates with the size and shape of monodisperse metal nanoparticle catalysts in structure sensitive reactions.close11111