We present a comprehensive analytical theory of localized nonlinear excitations-dark solitons-supported by an incoherently pumped, spatially homogeneous exciton-polariton condensate. We show that, in ...contrast to dark solitons in conservative systems, these nonlinear excitations "relax" by blending with the background at a finite time, which critically depends on the parameters of the condensate. Our analytical results for trajectory and lifetime are in excellent agreement with direct numerical simulations of the open-dissipative mean-field model. In addition, we show that transverse instability of quasi-one-dimensional dark stripes in a two-dimensional open-dissipative condensate demonstrates features that are entirely absent in conservative systems, as creation of vortex-antivortex pairs competes with the soliton relaxation process.
Mitochondrial dysmorphology/dysfunction follow global cerebral ischemia-reperfusion (GCI/R) injury, leading to neuronal death. Our previous researches demonstrated that Levodopa (L-DOPA) improves ...learning and memory impairment in GCI/R rats by increasing synaptic plasticity of hippocampal neurons. This study investigates if L-DOPA, used in Parkinson's disease treatment, alleviates GCI/R-induced cell death by enhancing mitochondrial quality. Metabolomics and transcriptomic results showed that GCI/R damage affected the Tricarboxylic acid (TCA) cycle in the hippocampus. The results of this study show that L-DOPA stabilized mitochondrial membrane potential and ultrastructure in hippocampus of GCI/R rats, increased dopamine level in hippocampus, decreased succinic acid level, and stabilized Ca2+ level in CA1 subregion of hippocampus. As a precursor of dopamine, L-DOPA is presumed to improves mitochondrial function in hippocampus of GCI/R rats. However, dopamine cannot cross the blood-brain barrier, so L-DOPA is used in clinical therapy to supplement dopamine. In this investigation, OGD/R models were established in isolated mouse hippocampal neurons (HT22) and primary rat hippocampal neurons. Notably, dopamine exhibited a multifaceted impact, demonstrating inhibition of mitochondrial reactive oxygen species (mitoROS) production, stabilization of mitochondrial membrane potential and Ca2+ level, facilitation of TCA circulation, promotion of aerobic respiratory metabolism, and downregulation of succinic acid-related gene expression. Consistency between in vitro and in vivo results underscores dopamine's significant neuroprotective role in mitigating mitochondrial dysfunction following global cerebral hypoxia and ischemia injury. Supplement dopamine may represent a promising therapy to the cognitive impairment caused by GCI/R injury.
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•GCI/R causes hippocampal mitochondrial respiratory dysfunction.•L-DOPA or dopamine stabilizes Ca2+ level, the mitochondrial structure and function in the hippocampus of GCI/R-injured rats.•L-DOPA or dopamine is a potential novel mitochondrial regulator.•Supplement dopamine may represent a promising therapy to the cognitive impairment caused by GCI/R injury.
ROS-dependent induction of oxidative damage can be used as a trigger initiating genetically determined non-specific protection in plant cells and tissues. Plants are potentially able to withstand ...various specific (toxic, osmotic) factors of abiotic effects, but do not have sufficient or specific sensitivity to form an adequate effective response. In this work, we demonstrate one of the possible approaches for successful cold acclimation through the formation of effective protection of photosynthetic structures due to the insertion of the heterologous
gene into the tobacco genome under the control of the constitutive promoter and equipped with a signal sequence targeting the protein to plastid. The increased enzymatic activity of superoxide dismutase in the plastid compartment of transgenic tobacco plants enables them to tolerate the oxidative factor of environmental stresses scavenging ROS. On the other hand, the cost of such resistance is quite high and, when grown under normal conditions, disturbs the arrangement of the intrachloroplastic subdomains leading to the modification of stromal thylakoids, probably significantly affecting the photosynthesis processes that regulate the efficiency of photosystem II. This is partially compensated for by the fact that, at the same time, under normal conditions, the production of peroxide induces the activation of ROS detoxification enzymes. However, a violation of a number of processes, such as the metabolism of accumulation, and utilization and transportation of sugars and starch, is significantly altered, which leads to a shift in metabolic chains. The expected step for further improvement of the applied technology could be both the use of inducible promoters in the expression cassette, and the addition of other genes encoding for hydrogen peroxide-scavenging enzymes in the genetic construct that are downstream in the metabolic chain.
In our research, we have developed and conducted a survey to determine the quality of implementation and organisation of ICT from the point of view of university students. The study was conducted in ...two groups of students, intramural and extramural, to identify a common problem of domestic education. The survey focuses on various aspects: a student view of education programme innovativeness, teachers’ participation in the ICT introduction, and the technological support in selected universities. These developments can be useful for universities that faced with the problem of introducing innovation and communication technologies. The recommendations described in the research can be used as a solution to the current problems associated with the organisation of ICT. On the way to solving the problem of using and introducing innovative technologies in higher education, it is very important to reorganize all aspects: completeness of education programmes, technological literacy of teachers and technical support provided by universities.
Various abiotic stresses cause the appearance of reactive oxygen species (ROS) in plant cells, which seriously damage the cellular structures. The engineering of transgenic plants with higher ...production of ROS-scavenging enzyme in plant cells could protect the integrity of such a fine intracellular structure as the cytoskeleton and each cellular compartment. We analyzed the morphological changes in root tip cells caused by the application of iso-osmotic NaCl and Na
SO
solutions to tomato plants harboring an introduced superoxide dismutase gene. To study the roots of tomato plants cultivar Belyi Naliv (WT) and FeSOD-transgenic line, we examined the distribution of ROS and enzyme-linked immunosorbent detection of α-tubulin. In addition, longitudinal sections of the root apexes were compared. Transmission electronic microscopy of atypical cytoskeleton structures was also performed. The differences in the microtubules cortical network between WT and transgenic plants without salt stress were detected. The differences were found in the cortical network of microtubules between WT and transgenic plants in the absence of salt stress. While an ordered microtubule network was revealed in the root cells of WT tomato, no such degree of ordering was detected in transgenic line cells. The signs of microtubule disorganization in root cells of WT plants were manifested under the NaCl treatment. On the contrary, the cytoskeleton structural organization in the transgenic line cells was more ordered. Similar changes, including the cortical microtubules disorganization, possibly associated with the formation of atypical tubulin polymers as a response to salt stress caused by Na
SO
treatment, were also observed. Changes in cell size, due to both vacuolization and impaired cell expansion in columella zone and cap initials, were responsible for the root tip tissue modification.
Metabolic syndrome (MetS) is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum ...high-density lipoprotein (HDL). Antipsychotic (AP)-induced MetS (AIMetS) is the most common adverse drug reaction (ADR) of psychiatric pharmacotherapy. Herein, we review the results of studies of blood (serum and plasma) and urinary biomarkers as predictors of AIMetS in patients with schizophrenia (Sch). We reviewed 1440 studies examining 38 blood and 19 urinary metabolic biomarkers, including urinary indicators involved in the development of AIMetS. Among the results, only positive associations were revealed. However, at present, it should be recognized that there is no consensus on the role of any particular urinary biomarker of AIMetS. Evaluation of urinary biomarkers of the development of MetS and AIMetS, as one of the most common concomitant pathological conditions in the treatment of patients with psychiatric disorders, may provide a key to the development of strategies for personalized prevention and treatment of the condition, which is considered a complication of AP therapy for Sch in clinical practice.
A method is described for the direct detection of unstable cysteine peptidase activity in polyacrylamide gels after native electrophoresis using new selective fluorogenic peptide substrates, ...pyroglutamyl-phenylalanyl-alanyl-4-amino-7-methylcoumaride (Glp-Phe-Ala-AMC) and pyroglutamyl-phenylalanyl-alanyl-4-amino-7-trifluoromethyl-coumaride (Glp-Phe-Ala-AFC). The detection limit of the model enzyme papain was 17 pmol (0.29 μg) for Glp-Phe-Ala-AMC and 43 pmol (0.74 μg) for Glp-Phe-Ala-AFC, with increased sensitivity and selectivity compared to the traditional method of protein determination with Coomassie G-250 staining or detection of activity using chromogenic substrates. Using this method, we easily identified the target digestive peptidases of Tenebrio molitor larvae by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis. The method offers simplicity, high sensitivity, and selectivity compared to traditional methods for improved identification of unstable cysteine peptidases in multi-component biological samples.
•A method is described to detect cysteine peptidase activity in biological mixtures using new selective fluorogenic peptide substrates after native electrophoresis.•The method was used to rapidly identify an insect larval gut cysteine peptidase by MALDI-TOF and MS analysis.•The method offers increased sensitivity and selectivity compared to protein staining with Coomassie G-250 or activity detection using chromogenic substrates.
Entosis, or cell death by invading another cell, is typical for tumor epithelial cells. The formation of cell-in-cell structures is extensively studied in suspension cultures, but remains poorly ...understood in substrate-dependent cells. Here, we used electron, confocal and time-lapse microscopy in combination with pharmacological inhibition of intracellular components to study the kinetics of entosis using two human substrate-dependent tumor cultures, A431 and MCF7. In total, we identified and characterized five consecutive stages of entosis, which were common for both examined cell lines. We further demonstrated that actin filaments in the entotic as well as invading cells were crucial for entosis. Microtubules and the Golgi apparatus of entotic cells provided membrane expansion required for internalization of the invading cell. Depolymerization of microfilaments and microtubules, and disintegration of the Golgi complex inhibited entosis. We confirmed the presence of adhesive junctions and discovered the formation of desmosomes between the invading and entotic cells. The internalized cell was shown to be degraded due to the lysosomal activation in both cells whereas the disintegration of the Golgi apparatus did not affect the process. Thus, in the substrate-dependent cultures, entosis requires microfilaments, microtubules and the Golgi complex for cell invasion, but not for internalized cell degradation.
The improvement of the agricultural sector efficiency, a shift to innovative development approaches to increase the competitiveness of domestic agriculture in modern conditions is possible only if ...labor productivity increases. This task is more relevant today than ever, since the main factor of production – labor (labor resources) has a steady downward trend. The study has shown that in the agricultural sector of the region there is an increase of labor productivity both by value and volume. The application of deterministic factor analysis has revealed that in the dynamics both factors (number of employees and cost of production) had a positive impact on increasing labor productivity, but the increase in production volumes in the industry had a more noticeable effect (the value of the factor varied from 57.7 to 69.7 %). However due regard must be paid to the fact that agricultural production is subject to fluctuations and the decrease in the number of workers in the industry is sustainable. The positive impact and the main factor in the growth of annual labor productivity is an increase in the average hourly output of workers due to an increase in the yield and technical re-equipment, and this should be noted as a strategically important direction for the development of the industry. The normalization of employment also acts as a factor in further increasing labor productivity.
The integumentary tissues of plant seeds protect the embryo (new sporophyte) forming in them from unfavorable external conditions; therefore, comprehensive knowledge about the structural and ...functional specificity of seed covers in various plants may be of both theoretical and practical interest. As a result of our study, additional data were obtained on the morphological and ultrastructural features of the formation of a multilayer skin of wheat (Triticum aestivum L.) kernel (caryopsis). The ultrastructure research analysis showed that differentiation of the pericarp and inner integument of the ovule leads to the formation of functionally different layers of the skin of mature wheat grain. Thus, the differentiation of exocarp and endocarp cells is accompanied by a significant thickening of the cell walls, which reliably protect the ovule from adverse external conditions. The cells of the two-layer inner integument of the ovule differentiate into cuticular and phenolic layers, which are critical for protecting daughter tissues from various pathogens. The epidermis of the nucellus turns into a layer of mucilage, which apparently helps to maintain the water balance of the seed. Morphological and ultrastructural data showed that the formation of the kernel’s skin occurs in coordination with the development of the embryo and endosperm up to the full maturity of the kernel. This is evidenced by the structure of the cytoplasm and nucleus, characteristic of metabolically active protoplasts of cells, which is observed in most integumentary layers at the late stages of maturation. This activity can also be confirmed by a significant increase in the thickness of the cell walls in the cells of two layers of the exocarp and in cross cells in comparison with the earlier stages. Based on these results, we came to the conclusion that the cells of a majority in the covering tissues of the wheat kernel during its ontogenesis are transformed into specialized layers of the skin by terminal differentiation.
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