Postsynaptic Mechanisms Are Essential for Forskolin-Induced Potentiation of Synaptic Transmission

It has been demonstrated that stimulation of protein kinase A (PKA) results in enhanced synaptic transmission in the hippocampus and other brain areas. To investigate mechanisms of the PKA-mediated potentiation of synaptic transmission, we used rat hippocampal embryonic cultures. In low-density cultures, paired recordings under the perforated patch demonstrated that 15-min forskolin treatment produced long-lasting potentiation of evoked excitatory postsynaptic currents (eEPSCs) mediated by the cAMP/PKA pathway. eEPSC amplitudes increased to 240 ± 10% of baseline after 15 min of forskolin treatment (early). After forskolin washout, eEPSCs declined to a potentiated level. Potentiation was sustained for ≥85 min after forskolin washout and, 60 min after forskolin washout, constituted 152 ± 7% of baseline (late potentiation). Disruption of presynaptic processes with the whole cell configuration and internal solution containing PKA inhibitor peptide did not affect forskolin-induced potentiation. Disruption of postsynaptic processes, in contrast, impaired early potentiation and abolished late potentiation. Study of mEPSCs confirmed the contribution of postsynaptic mechanisms. Forskolin-induced enhancement of mEPSC frequency observed under the perforated patch was attenuated by the whole cell configuration. Forskolin also induced an increase of mEPSC amplitudes in the perforated patch, but not in the whole cell, experiments. Potentiation of eEPSCs was not activity dependent, persisting in the absence of stimulation. NMDA receptor blockade did not abolish forskolin-induced potentiation. In summary, we demonstrate that forskolin-induced potentiation of eEPSCs was mediated by postsynaptic mechanisms, presumably by upregulation of AMPA receptors by phosphorylation

The study of spectral and luminescent properties of humic acids and their impact on the photodegradation process of 2,6-bis(hydroxymethyl)-4-methylphenol

UV photolysis (KrCl excilamp, λ rad ~ 222 nm) of aqueous humic acids (HAs) samples was carried out without and in the presence of 2,6-bis(hydroxymethyl)-4-methylphenol. The samples of HAs fractions were obtained from Aldrich Chemical Co and prepared from peat of Arkhangelsk region. The presence of Aldrich humic acid in the solution has a essential effect on the processes of phenolic compound photochemical degradation under the action of light from the excilam

AGEISM AND STIGMATIZATION OF ELDERLY PEOPLE BY REPRESENTATIVES OF DIFFERENT GENERATIONS: A COMPARATIVE ANALYSIS

Aim. To conduct a comparative analysis of stereotypes and ageism attitudes towards elderly people among representatives of different generations (youth, middle-aged people and elderly people themselves).Methodology. The study was conducted using a nonparametric criterion for comparing several independent samples - the Kruskal-Wallis test. Methods were used to study attitudes, attitudes towards ageism and semantic differential.Results. In the structure of stigmatizing attitudes of all three generations, prejudices about elderly people are most frequent, and to the greatest extent they are present among elderly people themselves, which makes it possible to talk about self-stigmatization. Discriminatory attitudes are least expressed in the structure of ageism in all age groups, but attitudes to avoid contact with the elderly are statistically significantly more present in the group of young people aged 18 - 35.Research implications. The results obtained can be used in building productive communications in transgenerational relationships and become the basis for the development of specialized training programs aimed at counteracting the formation of social stigmatization of elderly people.</html

Mitochondrial Electron Transport Chain in Heavy Metal-Induced Neurotoxicity: Effects of Cadmium, Mercury, and Copper

To clarify the role of mitochondrial electron transport chain (mtETC) in heavy-metal-induced neurotoxicity, we studied action of Cd2+, Hg2+, and Cu2+ on cell viability, intracellular reactive oxygen species formation, respiratory function, and mitochondrial membrane potential of rat cell line PC12. As found, the metals produced, although in a different way, dose- and time-dependent changes of all these parameters. Importantly, Cd2+ beginning from 10 [mu]M and already at short incubation time (3 h) significantly inhibited the FCCP-uncoupled cell respiration; besides, practically the complete inhibition of the respiration was reached after 3 h incubation with 50 [mu]M Hg2+ or 500 [mu]M Cd2+, whereas even after 48 h exposure with 500 [mu]M Cu2+, only a 50% inhibition of the respiration occurred. Against the Cd2+-induced cell injury, not only different antioxidants and mitochondrial permeability transition pore inhibitors were protective but also such mtETC effectors as FCCP and stigmatellin (complex III inhibitor). However, all mtETC effectors used did not protect against the Hg2+- or Cu2+-induced cell damage. Notably, stigmatellin was shown to be one of the strongest protectors against the Cd2+-induced cell damage, producing a 15–20% increase in the cell viability. The mechanisms of the mtETC involvement in the heavy-metal-induced mitochondrial membrane permeabilization and cell death are discussed

Methods of Social Interaction Learning for Students of Non-Profit Organizations

Search and substantiation of new form productivity for student non-formal education, which make it possible to compensate for the deficit of purposeful preparation for social interaction in the traditional (formal) system of higher education. Methodology: system-dialectical approach, which allows to overcome the existing fragmentation and the fragmentation of research results concerning the experience of student social interaction; the methods of scientific analysis of sources; pedagogical experience study; comparative analysis; classification; content analysis; mathematical processing of statistical data. Results: they substantiate the relevance of addressing social education of students in youth non-profit organizations, as one of the forms of non-formal education. The individual and group experience of social interaction and its promising lines of enrichment (subjectivity, reflexivity, co-existence) are proposed as a system-organized educational result. The content of education is determined based on the characteristics of social practices implemented in non-profit organizations. The results of the comparative study of the applied forms and methods of youth training in existing youth non-profit organizations in Russia and abroad (the Association of Trainers of the Russian Union of Youth, the All-Russian School of Personal Growth and Development of Student Self-Government "Progress", "The College of Trainers by T. Hoist" (Germany), "Freechild Institute" (USA). The methods of social training of their participants most widespread in non-profit organizations, the features and results of their application are determined. The conclusions are made about the relevance and prospects of student youth preparation optimization for active social interaction in non-formal education within the context of non-profit organizations based on the methodology of the system-dialectical approach to the enrichment of individual and group experience of social interaction