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Dengue virus NS1 is a glycoprotein of 46-50kDa which associates as a dimer to internal and cytoplasmic membranes and is also secreted, as a hexamer, to the extracellular milieu. However, the notion exist that NS1 is secreted only from infected vertebrate and not mosquito cells. In this work, evidence is presented showing that NS1 is secreted efficiently by infected mosquito cells. NS1 was detected in cell supernatants starting at 6hpi with a continuous concentration increase up to 24hpi. Nevertheless, cell viability showed an average cell survival of 97%. At variance with observations with vertebrate cells, NS1 does not seems to associate with the cytoplasmic membrane of insect cells. Finally, evidence is presented indicating that NS1 is secreted from insect cells as a barrel-shaped hexamer. These findings provide new insights into the biology of NS1 and open questions about the role of secreted NS1 in the vector mosquito.

B-lymphocytes are migrating cells that specialize in antigen presentation, antibody secretion, and endocytosis; these processes implicate the modulation of plasma membrane elasticity. Cell stiffness is a force generated by the interaction between the actin-cytoskeleton and the plasma membrane, which requires the participation of several proteins. These proteins include class I myosins, which are now considered to play a role in controlling membrane-cytoskeleton interactions. In this study, we identified the motor protein Myosin 1g (Myo1g) as a mediator of this phenomenon. The absence of Myo1g decreased the cell stiffness, affecting cell adhesion, cell spreading, phagocytosis, and endocytosis in B-lymphocytes. The results described here reveal a novel molecular mechanism by which Myo1g mediates and regulates cell stiffness in B-lymphocytes. © 2016 Wiley Periodicals, Inc.

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The oxidation of 4‐(4‐nitrophenyl)butyrate ions in acetonitrile was used to modify glassy carbon surfaces with films bearing 3‐(4‐nitrophenyl)propyl groups. The main features of the voltammetric reduction of the grafted nitrophenyl groups were studied in two different supporting electrolytes; n‐Bu4NPF6 and Me4NPF6. The best response was obtained with the less bulky electrolyte, which was explained by the major capability of these ions to diffuse inside the channels of the grafted film, as well as the better stabilization of the radical anions generated during the reduction process. It was also shown that the films electrografted in presence of the bulky n‐Bu4NPF6 are thicker but less compact than those prepared in Me4NPF6. The amount of nitrophenyl groups in the grafted film that can be reduced depends on the size of the electrolyte ions. The permeation of the electrolyte ions inside the film channels determines also the voltammetric behavior of ferrocene as redox probe. A current rectification phenomenon was observed in acetonitrile solutions of bulky and hydrophobic electrolytes like n‐Bu4NPF6 and n‐Hx4NPF6, whose marginal inclusion inside the film channels promotes both the entrance of ferrocene and the expelling of ferrocenium ions from these ones. This phenomenon was emulated through a CEC mechanism in solution, where the diffusion inside the channels was described as single chemical equilibria.

We performed a complex secondary ion mass spectroscopy (SIMS) 3D analysis of solar cell structures based on II-VI semiconductors. The chemical composition analysis, as well as the depth distribution of the main elements and contamination were done for AuCu/CdTe/CdS/conducting glass structures. A structure where the II-VI compounds were grown by pulsed laser ablation (PLA) was compared with another structure grown by ion sputtering deposition (ISD). In both cases contamination due to O, C and H was found at high concentrations, particularly at the boundaries between crystallites. In addition to the SIMS depth profiling, the surface roughness (SR) was analysed by atomic force microscopy (AFM). Poor SIMS depth resolution was correlated to high surface roughness. The root-mean-square of the surface roughness (R rms ) was found to be higher for ISD than for PLA structures. In addition, the lateral distribution of the main components and contamination were observed in the microscope mode with a resolution of about 1 µm. A larger lateral contamination was correlated to a larger R rms of the analysed surface. Experimental 'diffusion' tails of Cu and Au from the ohmic contacts on the CdTe layer are also explained by a high R rms for this layer.

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