Modulation of the voltage-gated sodium current in rat striatal neurons by DARPP-32, an inhibitor of protein phosphatase

DARPP-32 is a cyclic adenosine monophosphate-regulated inhibitor of protein phosphatase 1, highly enriched in striatonigral neurons. Stimulation of dopamine D1 receptors increases phosphorylation of DARPP-32, whereas glutamate acting on N-methyl-D-aspartate receptors induces its dephosphorylation. Yet, to date, there is little direct evidence for the function of DARPP-32 in striatal neurons. Using a whole cell patch-clamp technique, we have studied the role of DARPP-32 in the regulation of voltage-gated sodium channels in rat striatal neurons maintained in primary culture. Injection of phospho-DARPP-32, but not of the unphosphorylated form, reduced the sodium current amplitude. This effect was similar to those induced by okadaic acid, with which there was no additivity and by tautomycin. Our results indicate that, in striatal neurons, sodium channels are under dynamic control by phosphorylation/dephosphorylation, and that phospho-DARPP-32 reduces sodium current by stabilizing a phosphorylated state of the channel or an associated regulatory protein. We propose that the DARPP-32-mediated modulation of sodium channels, via inhibition of phosphatase 1, contributes to the regulation of these channels by D1 receptors and other neurotransmitters which influence the state of phosphorylation of DARPP-32.     

CuBr2‐induced charge screening on photoactive nanocolloidal polypyrrole:poly(styrene sulfonate) composite multilayer thin‐film counter electrodes for high‐efficiency dye‐sensitized solar cells

Nanocolloidal polypyrrole (PPy):poly(styrene sulfonate) (PSS) particles were synthesized by chemical oxidative polymerization using 15 wt% of PSS. The highly processable polymer composite (PPy:PSS) was spin‐coated at 4000 rpm on fluorine‐doped tin oxide glass and subsequently employed as a counter electrode (CE) for dye‐sensitized solar cells (DSCs). PPy:PSS multilayer (one, three, five) CEs were treated with CuBr₂ salt, which enhances the efficiency of the DSCs. Optical studies reveal that a bulkier counterion hinders interchain interactions of PPy which on salt treatment shows a moderate redshift in absorption maxima. Salt‐treated PPy:PSS films exhibit lower charge transfer resistance, higher surface roughness and better catalytic performance for the reduction of I₃^?, when compared with untreated films. The improved catalytic performance of salt‐treated PPy:PSS multilayer films is attributed to charge screening and conformational change of PPy, along with the removal of excess PSS. Under standard AM 1.5 sunlight illumination, salt treatment is shown to boost the efficiency of multilayer PPy:PSS composite film‐based DSCs, leading to enhanced power conversion efficiency of 6.18, 6.33 and 6.37% for one, three and five layers, respectively. These values are significantly higher (ca 50%) than those for corresponding devices without CuBr₂ salt treatment (3.48, 2.90 and 2.01%, respectively). © 2016 Society of Chemical Industry     

Using an APK-051 analyzer in a chemical engineering monitoring system

The capabilities of an APK-051 automatic analyzer for directly measuring the standardized indicators used for automatic chemical monitoring and indirectly determining the concentration of ammonia in water coolant are described.     

Russian and foreign millimeter band radio measuring instruments

The present state of the development and production of Russian and foreign radio-measuring instruments in the frequency range up to 178.4 GHz (and higher) and the proposed glossary of the new generation of Russian instruments are considered.     

Optimization of mismatch euclidean distance in evaluating interframe deformations of geometrical images

The criterion of optimization of the local sample plan used for finding of the estimation quality target function pseudogradient is proposed. Applications of the criterion are considered for the setting the mean squared interframe difference, covariance, and interframe correlation coefficient as a target function. Optimization aims to increase the estimation of the rate of convergence of the parameters of interframe deformations of geometrical images.     

Developing a chromium-bearing starting mixture from Ural raw materials

A chromium-bearing starting mixture derived from Ural raw materials is investigated. Its properties resemble those of imported Feurolan SM 70A20 mixture. Industrial tests show that the Russian version is competitive with the imported mixture.     

Neural network-based approximation of aircraft attainability boundary

The problem of the approximate dynamic system attainability domain boundary construction is considered. Results of neural network-based methods efficiency research for the highly-maneuverable aircraft attainability domain boundaries approximate construction are presented.