Role of HSC70 protein in maintenance of endoplasmic reticulum CA2+ homeostasis

Intracellular calcium homeostasis is disrupted in many neuronal diseases and traumatic brain injuries resulting in endoplasmic reticulum (ER) stress [1]. ER stress and intracellular calcium homeostasis is a hub of signaling mechanisms that determine whether injured neurons will live or die. With survivable injuries neurons seek to restore normal function by several mechanisms including the upregulation of chaperones [2]. Hsc70 (aka Hsp73 and HSPA8) is one of such proteins, which is found to be highly concentrated in neurons. Unlike other chaperones in the HSP family Hsc70 is constitutively expressed and interacts with both cell cycle and apoptosis regulating proteins [3]. Therefore, we tested the hypothesis that Hsc70 regulates neural stem cell fate in response to changes intracellular calcium homeostasis. Currently little is known about the function of this novel chaperone or about the role of ER calcium homeostasis in neural stem cell fate determination and this work is the first to investigate this topic

Assessment of collecting activity of physically sorbed reagents on the example of easily floatable coking coal sludge

The article presents one of the new approaches to theoretical assessment of collecting ability of reagents. The efficiency of reagents-collectors with different chemical composition used for flotation of coking coals was studied. A comparative assessment of the flotation activity of kerosene, mineral oil, thermal gas oil, KETGOL and FLOTEK is given. The criteria of collecting activity of the above reagents-collectors for coal sludge flotation were specified. A correlation was established between the indicators of coal sludge flotation by the above reagents and their physical parameters. It is shown that the rate of spreading over water surface can characterize the flotation activity of reagents. Based on dependence of the collecting activity of a reagent on its rate of spreading along the “gas – liquid” interface and surface pressure, the main approaches to determining the structure and composition of molecules of an effective flotation collector can be determined. A new concept of the function performed by a physically sorbed collector in the elementary act of flotation and a criterion for the flotation activity of reagents used in coal sludge beneficiation are proposed. It is shown that the collector used in coal flotation, in addition to hydrophobizing the surface of the extracted particles, should reduce the induction time and remove the kinetic constraint on formation of a flotation aggregate

Disposable potentiometric sensory system for skin antioxidant activity evaluation

The skin is a natural barrier between the external and internal environment. Its protective functions and the relationship of its state with the state of health of the organism as a whole are very important. It is known that oxidant stress (OS) is a common indicator of health status. This paper describes a new sensory system for monitoring OS of the skin using antioxidant activity (AOA) as its criteria. The contact hybrid potentiometric method (CHPM) and new electrochemical measuring scheme were used. A new sensory system, including disposable modified screen-printed carbon and silver electrodes covered by membrane impregnated by mediator, was developed. Its informative ability was demonstrated in the evaluation of the impact of fasting, consumption of food and food enriched by vitamins (antioxidants) on skin AOA. This device consisting of a sensory system and potentiometric analyzer can be used in on-site and in situ formats. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

The effect of the antioxidant activity of plant extracts on the properties of gold nanoparticles

Synthesis of gold nanoparticles (phyto-AuNPs) with the use of leaf extracts (phytosynthesis) is based on the concept of Green Chemistry. The present study is conducted to discuss how antioxidant activity (AOA) of extracts from plant leaves impacts on the kinetics of phytosynthesis, the size of the formed nanoparticles, and the stability of their nanosuspensions. Results show that the formation rate of phyto-AuNPs suspensions accelerate due to the increase in the AOA of the extracts. Accompanying the use of transmission electron microscopy (TEM), UV-Vis-spectrophotometry and dynamic light scattering (DLS), it also has been found that higher AOA of the extracts leads to a decrease in the size of phyto-AuNPs, an increase in the fraction of small (d ≤ 5 nm), and a decrease in the fraction of large (d ≥ 31–50 nm) phyto-AuNPs, as well as an increase in the zeta potential in absolute value. Phyto-AuNPs suspensions synthesized with the use of extracts are more resistant to destabilizing electrolytes and ultrasound, as compared to suspensions synthesized using sodium citrate. Thus, the AOA of the extract is an important parameter for controlling phytosynthesis and predicting the properties of phyto-AuNPs. The proposed approach can be applied to the targeted selection of plant extract that will be used for synthesizing nanoparticles with desired properties. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Russian Foundation for Basic Research, RFBR: 17-03-00679_АFunding: This research was funded by the Russian Foundation for Basic Research, grant number 17-03-00679_А

Fashioning of Students' Research Competence Through Technology of Project Activities

Objective: The authors provide justifications for changing the current education system, updating the teaching and methodological approach in school specialised education. The paper investigates the issue of fashioning students' research competence through the technology of project activities.Background: Project activity has become widely used since it combines the theoretical and practical parts of the science under study, which allows to set up a connection between its components. Research competence is an integral feature of a student's personality, which manifests itself in a willingness to take an active research position.Method: The authors conducted an experiment to study the problem of improving the quality of students' knowledge upon studying biology in senior school. The participants in the experiment were 120 students of the 10th and 11th years of a specialised school for children with psychological disorders.Results: The authors developed a methodology for the fashioning of research competence. The results of the conducted pedagogical experiment confirmed the validity of the initial assumptions regarding the influence of the use of research teaching methods in biology lessons aimed at improving the quality of biological education.Conclusion: Through project activities, students with intellectual disabilities learn to work in a team. Despite the fact that teamwork is uniting, each of the students learns to independently set the purpose and tasks of the study, analyse the sources presented, present the results of their activities to others. The main signs of project activity include the fact that students learn the technique and technology of working with the project. Project activity allows for the fashioning of students' research competence during the lesson, thereby enabling students to unleash their potential

Purinergic regulation of rat heart function in ontogeny

The effect of exogenous ATP and its analogs on heart function was studied in 14-100-day-old rats. Extracellular purines had a positive chronotropic effect on the heart. Intravenous administration of exogenous ATP and its stable analogs induced a dose-dependent increase in heart rate depending on animal age. The analysis of isometric contraction of myocardial strips demonstrated a dose-dependent positive inotropic effect of ATP. The family and subtype of the P2 receptors realizing the positive chronotropic and inotropic effects were identified using selective agonists and blockers. P2X receptors demonstrated the highest sensitivity during early postnatal ontogeny. The age-related pattern of the receptor response to exogenous purines indicated the heterochronic maturation of P2X and P2Y receptors in the myocardium. © 2008 MAIK Nauka

Evaluation of the Reform Efficiency in Public Social Sector Management of the Republic of Kazakhstan

The paper aims at studying the retrospective public administration reform the social sphere, the classification of its main results, and formation of proposals for further improvement of public governance. As a result, authors implemented a comprehensive systematization of the key stages of the reform and measures taken to improve the functioning of the institute of public administration in the social sphere of the Republic of Kazakhstan in the context of administrative and social reforms. The results of the reforms are determined; the shortcomings of state control over the implementation of social programs are identified. Article suggests the prospects and directions of development of the social protection system in the Republic of Kazakhstan with an account of current socio-economic conditions and the parameters of international social standards. DOI: 10.5901/mjss.2015.v6n3s5p19

VOLTAMPEROMETRIC DETERMINATION OF NITRITE IONS IN NATURAL WATERS

The article discusses the main sources of environmental pollution with nitrite ions. The need for monitoring the nitrite content in environmental objects is shown, since nitrite ions are toxic substances that can harm human health. The development of an electrochemical sensor for the fast and accurate determination of nitrite ions in natural waters is discussed.В статье рассматриваются основные источники загрязнения окружающей среды нитрит-ионами. Показана необходимость контроля за содержанием нитритов в объектах окружающей среды, так как нитрит-ионы относятся к токсичным веществам, способным нанести вред здоровью человека. Обсуждается разработка электрохимического сенсора для быстрого и точного определения нитрит-ионов в природных водах