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

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

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

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

Carbon Paper Modified with Functionalized Poly(diallyldimethylammonium chloride) Graphene and Gold Phytonanoparticles as a Promising Sensing Material: Characterization and Electroanalysis of Ponceau 4R in Food Samples

This paper presents a novel eco-friendly sensing material based on carbon paper (CP) volumetrically modified with a composite nanomodifier that includes functionalized poly(diallyldimethylammonium chloride) graphene (PDDA-G) and phytosynthesized gold nanoparticles (phyto-AuNPs). The functionalization of graphene was justified by Fourier-transform infrared spectroscopy. The phyto-AuNPs (d = 6 nm) were prepared by “green” synthesis with the use of strawberry leaf extract. The sensing material was characterized using scanning electron microscopy, electrochemical impedance spectroscopy, and voltammetry. The research results indicated a more than double increase in the electroactive surface area; a decrease in the resistance of electron transfer on nanocomposite-modified CP, compared to bare CP. The phyto-AuNPs/PDDA-G/CP was used for the electrosensing of the synthetic dye Ponceau 4R. The oxidation signal of colorant enhanced 4-fold on phyto-AuNPs/PDDA-G/CP in comparison to CP. The effect of the quantity of nanomodifier, solution pH, potential scan rate, accumulation parameters, and differential pulse parameters on the peak current of Ponceau 4R was studied. Under optimal conditions, excellent sensory characteristics were established: LOD 0.6 nM and LR 0.001–2 μM for Ponceau 4R. High selectivity and sensitivity enable the use of the sensor for analyzing the content of Ponceau 4R in food products (soft drinks, candies, and popsicles) without additional sample preparation. © 2022 by the authors

A water accounting procedure to determine the water savings potential of the Fergana Valley

The Syrdarya River basin in Central Asia exhibits symptoms of scarcity because of growing competition between hydropower upstream and environment, cities and agriculture downstream. Different approaches to water management, based on water savings in agriculture could relieve the stress of competition, yet keep alive a vibrant agriculture. The Fergana Valley, a highly productive area within the upstream of the Syrdarya River, was analyzed to determine the water savings potential of agriculture. This paper used a water accounting procedure to identify both the scope for savings and the strategies to realize those gains. Significant nonproductive depletion of water at 2681�4164 million m3 (Mm3) was identified in the form of evaporation, flows to sinks and pollution. The water-saving potential is estimated at 2823 Mm3 annually, which is about 10% of the total inflow into the area, through a range of practical approaches. This strategy would bring regional benefits by reallocation of surplus winter flow from the upstream for summer use in the downstream