Activation of Gq-Coupled Receptors in Astrocytes Restores Cognitive Function in Alzheimer’s Disease Mice Model

Alzheimer’s disease (AD) is one of the most widespread neurodegenerative diseases. Most of the current AD therapeutic developments are directed towards improving neuronal cell function or facilitating Aβ amyloid clearance from the brain. However, some recent evidence suggests that astrocytes may play a significant role in the pathogenesis of AD. In this paper, we evaluated the effects of the optogenetic activation of Gq-coupled exogenous receptors expressed in astrocytes as a possible way of restoring brain function in the AD mouse model. We evaluated the effects of the optogenetic activation of astrocytes on long-term potentiation, spinal morphology and behavioral readouts in 5xFAD mouse model of AD. We determined that in vivo chronic activation of astrocytes resulted in the preservation of spine density, increased mushroom spine survival, and improved performance in cognitive behavioral tests. Furthermore, chronic optogenetic stimulation of astrocytes resulted in the elevation of EAAT-2 glutamate uptake transporter expression, which could be a possible explanation for the observed in vivo neuroprotective effects. The obtained results suggest that the persistent activation of astrocytes may be considered a potential therapeutic approach for the treatment of AD and possibly other neurodegenerative disorders

Influence of the LaMn1−xFexO3 (x = 0–1) Composition on Catalytic Activities in the Reactions Involving Oxygen

Perovskite samples of the LaMn1−xFexO3 (x = 0–1) series were prepared by the Pechini method; their physicochemical properties were studied using XRD, HRTEM, XPS, and BET, and their catalytic activity was estimated in nitrous oxide decomposition and methane and CO oxidation reactions. In methane and CO oxidation reactions, all intermediate (0 < x < 1) samples of the series exhibited a lower catalytic activity normalized to the unit surface area as compared to the extreme terms, whereas in the nitrous oxide decomposition all intermediate samples were more active than extreme terms of the series. Different dependences of activities on the composition obtained in the study for the tested reactions involving the catalyst oxygen are caused by differences in the reaction mechanisms

Influence of the LaMn_1−xFe_xO₃ (x = 0–1) Composition on Catalytic Activities in the Reactions Involving Oxygen

Perovskite samples of the LaMn1−xFexO3 (x = 0–1) series were prepared by the Pechini method; their physicochemical properties were studied using XRD, HRTEM, XPS, and BET, and their catalytic activity was estimated in nitrous oxide decomposition and methane and CO oxidation reactions. In methane and CO oxidation reactions, all intermediate (0 < x < 1) samples of the series exhibited a lower catalytic activity normalized to the unit surface area as compared to the extreme terms, whereas in the nitrous oxide decomposition all intermediate samples were more active than extreme terms of the series. Different dependences of activities on the composition obtained in the study for the tested reactions involving the catalyst oxygen are caused by differences in the reaction mechanisms

NeuroActivityToolkit—Toolbox for Quantitative Analysis of Miniature Fluorescent Microscopy Data

The visualization of neuronal activity in vivo is an urgent task in modern neuroscience. It allows neurobiologists to obtain a large amount of information about neuronal network architecture and connections between neurons. The miniscope technique might help to determine changes that occurred in the network due to external stimuli and various conditions: processes of learning, stress, epileptic seizures and neurodegenerative diseases. Furthermore, using the miniscope method, functional changes in the early stages of such disorders could be detected. The miniscope has become a modern approach for recording hundreds to thousands of neurons simultaneously in a certain brain area of a freely behaving animal. Nevertheless, the analysis and interpretation of the large recorded data is still a nontrivial task. There are a few well-working algorithms for miniscope data preprocessing and calcium trace extraction. However, software for further high-level quantitative analysis of neuronal calcium signals is not publicly available. NeuroActivityToolkit is a toolbox that provides diverse statistical metrics calculation, reflecting the neuronal network properties such as the number of neuronal activations per minute, amount of simultaneously co-active neurons, etc. In addition, the module for analyzing neuronal pairwise correlations is implemented. Moreover, one can visualize and characterize neuronal network states and detect changes in 2D coordinates using PCA analysis. This toolbox, which is deposited in a public software repository, is accompanied by a detailed tutorial and is highly valuable for the statistical interpretation of miniscope data in a wide range of experimental tasks

The microhardness and internal stresses allocation in superheating pipes welded node made of dissimilar steels

The object of research is the welded knot made of dissimilar steels 12Cr1MoV and Di-59. Research methods are spectral analysis, microhardness measurements and X-ray analysis. It is established that the structural-phase nonuniformity, significant concentration fluctuations of alloying elements, the spread in values of microhardness and mechanical characteristics along the length of the pipe can cause significant value of internal macrostress that leads to the formation of the “flaw” defect type in the welding process. It is shown how to distinguish between flaws that have appeared on the stage of production from operating flaws

The microhardness and internal stresses allocation in superheating pipes welded node made of dissimilar steels

The object of research is the welded knot made of dissimilar steels 12Cr1MoV and Di-59. Research methods are spectral analysis, microhardness measurements and X-ray analysis. It is established that the structural-phase nonuniformity, significant concentration fluctuations of alloying elements, the spread in values of microhardness and mechanical characteristics along the length of the pipe can cause significant value of internal macrostress that leads to the formation of the “flaw” defect type in the welding process. It is shown how to distinguish between flaws that have appeared on the stage of production from operating flaws

Effect of MAF-6 Crystal Size on Its Physicochemical and Catalytic Properties in the Cycloaddition of CO2 to Propylene Oxide

Zeolitic imidazolate frameworks MAF-5 and MAF-6 based on Zn2+ and 2-ethylimidazole were demonstrated to be efficient heterogeneous catalysts in solvent-free coupling of CO2 and propylene oxide (PO) to produce propylene carbonate (PC) at 0.8 MPa of CO2 and 80 °C. Activity of MAF-5 was lower in comparison with MAF-6 due to the difference in their structural and textural characteristics. MAF-6 samples with particle size of 190 ± 20, 360 ± 30, and 810 ± 30 nm were prepared at room temperature from [Zn(NH3)4](OH)2 and 2-ethylimidazole. Control of particle size was achieved by variation of type of alcohol in alcohol/cyclohexane media for the preparation of MAF-6. According to this comprehensive study, the yield of PC was found to decrease with increasing crystal size of the MAF-6 material, which was related to the change in textural properties and the number and localization of active sites. The combination of MAF-6 with particle size of with particle size of 190 ± 20 nm and tetrabutylammonium bromide ([n-Bu4N]Br) as co-catalyst led to an approximately 4-fold enhancement in the yield of PC (80.5%). Compared with reported ZIFs catalysts, the efficiencies of MAF-5/[n-Bu4N]Br and MAF-6/[n-Bu4N]Br binary systems were comparable and higher under similar reaction conditions

Genesis Investigation of Niand Mo-Based Dispersed Catalysts of Steam Cracking of Heavy Oil

В данной статье приведены результаты исследования генезиса Ni- и Mo-содержащего дисперсного катализатора парового крекинга, полученного эмульсионным методом in-situ в тяжелой нефти методами МУРР и ПЭМ. Впервые исследованы структурные характеристики катализаторов и его предшественников на всех этапах получения и применения: в обратной эмульсии, дисперсии и в коксовом остатке, полученном в ходе каталитического парового крекинга. Показано, что Ni-содержащий предшественник преобразуется в более крупные агрегаты при переходе от дисперсии в тяжелой нефти до частиц Ni9S8 с размерами частиц 10–40 нм в коксовом остатке. В случае молибдена данной зависимости выявлено не было, после проведения процесса парового крекинга образуется два типа частиц: мелкие слоистые частицы сульфида молибдена с протяженностью 10–15 нм и более крупные частицы оксида молибдена с размерами 20–30 нмThis article presents the results of the genesis investigation of Ni- and Mo-based dispersed steam cracking catalyst produced via in-situ heavy oil emulsion decomposition. The structural characteristics of catalysts and their precursors have been studied by SAXS and TEM for the first time at all stages of production and operation: in reverse emulsions, dispersions and in the coke residues obtained after catalytic steam cracking process It is shown that the Ni-based precursor is converted to larger aggregates during transition from a dispersion in heavy oil to Ni9S8 10-40 nm particles in the coke residue. In the case of molybdenum this trend was not revealed, after steam cracking process two types of particles are formed: small layered MoS2 particles with a length of 10-15 nm and larger MoO2 20-30 nm particle

An Open-Source Wireless Electrophysiological Complex for In Vivo Recording Neuronal Activity in the Rodent’s Brain

Multi-electrode arrays (MEAs) are a widely used tool for recording neuronal activity both in vitro/ex vivo and in vivo experiments. In the last decade, researchers have increasingly used MEAs on rodents in vivo. To increase the availability and usability of MEAs, we have created an open-source wireless electrophysiological complex. The complex is scalable, recording the activity of neurons in the brain of rodents during their behavior. Schematic diagrams and a list of necessary components for the fabrication of a wireless electrophysiological complex, consisting of a base charging station and wireless wearable modules, are presented