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1.
Basic Clin Neurosci ; 14(2): 297-309, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38107533

RESUMO

Introduction: Video games affect the stress system and cognitive abilities in different ways. Here, we evaluated electrophysiological and biochemical indicators of stress and assessed their effects on cognition and behavioral indexes after playing a scary video game. Methods: Thirty volunteers were recruited into two groups as control and experimental. The saliva and blood samples were collected before and after intervention (watching/playing the scary game for control and experimental groups respectively). To measure cortisol and salivary alpha-amylase (sAA) levels, oxytocin (OT), and brain-derived neurotrophic factor (BDNF) plasma levels, dedicated ELISA kits were used. Electroencephalography recording was done before and after interventions for electroencephalogram (EEG)-based emotion and stress recognition. Then, the feature extraction (for mental stress, arousal, and valence) was done. Matrix laboratory (MATLAB) software, version 7.0.1 was used for processing EEG-acquired data. The repeated measures were applied to determine the intragroup significance level of difference. Results: Scary gameplay increases mental stress (P<0.001) and arousal (P<0.001) features and decreases the valence (P<0.001) one. The salivary cortisol and alpha-amylase levels were significantly higher after the gameplay (P<0.001 for both). OT and BDNF plasma levels decreased after playing the scary game (P<0.05 for both). Conclusion: We conclude that perceived stress considerably elevates among players of scary video games, which adversely affects the emotional and cognitive capabilities, possibly via the strength of synaptic connections, and dendritic thorn construction of the brain neurons among players. Highlights: The mental stress level increases in players of scary video games.The salivary cortisol and alpha-amylase levels are significantly higher after the scary gameplay.Plasma levels of oxytocin and brain-derived neurotrophic factor decrease after the scary gameplay.The arousal and valence features increase in players of scary video game.Cognitive capabilities are adversely affected by the scary gameplay. Plain Language Summary: Nowadays, video games have become an important part of human life at different ages. Therefore, assessing their effects (improving and/or damaging) on cognition and behavior is important for understanding how they affect the nervous system. The results of such studies can be used to design a variety of games in the future in a way that minimizes the harmful side effects of video games on human cognitive functions and maximizes their beneficial effects.

2.
Materials (Basel) ; 16(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36984227

RESUMO

One-part geopolymer concrete/mortar is a pre-mixed material made from industrial by-products and solid alkaline activators that only requires the addition of water for activation. Apart from being environmentally friendly, it also reduces complexity and improves consistency in the mixing process, leading to more efficient production and consistent material properties. However, developing one-part geopolymer concrete with desirable compressive strength is challenging because of the complexity of the chemical reaction involved, the variability of the raw materials used, and the need for precise control of curing conditions. Therefore, 80 different one-part geopolymer mixtures were compiled from the open literature in this study, and the effects of the constituent materials, the dosage of alkaline activators, curing condition, and water/binder ratio on the 28-day compressive strength of one-part geopolymer paste were examined in detail. An ANN model with the Levenberg-Marquardt algorithm was developed to estimate one-part geopolymer's compressive strength and its sensitivity to binder constituents and alkaline dosage. The ANN model's weights and biases were also used to develop a CPLEX-based optimization method for achieving maximum compressive strength. The results confirm that the compressive strength of one-part geopolymer pastes increased by increasing the Na2O content of the alkaline source and the slag dosage; however, increasing the Na2O content in alkaline sources beyond 6% by fly ash weight led to decreasing the compressive strength; therefore, the optimum alkaline activator dosage by weight of fly ash was to be 12% (i.e., 6% Na2O). The proposed ANN model developed in this study can aid in the production and performance tuning of sustainable one-part geopolymer concrete and mortar for broader full-scale applications.

3.
Sci Rep ; 13(1): 1860, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725880

RESUMO

Endoplasmic reticulum (ER) stress is involved in the development of glucose homeostasis impairment. When ER stress occurs, the unfolded protein response (UPR) is activated to cope with it. One of the UPR components is WFS1 (Wolfram syndrome 1), which plays important roles in ER homeostasis and pancreatic islets glucose-stimulated insulin secretion (GSIS). Accordingly and considering that feeding high-fat food has a major contribution in metabolic disorders, this study aimed to investigate the possible involvement of pancreatic ER stress in glucose metabolism impairment induced by feeding high-fat diet (HFD) in male rats. After weaning, the rats were divided into six groups, and fed on normal diet and HFD for 20 weeks, then 4-phenyl butyric acid (4-PBA, an ER stress inhibitor) was administered. Subsequently, in all groups, after performing glucose tolerance test, the animals were dissected and their pancreases were removed to extract ER, islets isolation and assessment of GSIS. Moreover, the pancreatic ER stress [binding of immunoglobulin protein (BIP) and enhancer-binding protein homologous protein (CHOP)] and oxidative stress [malondialdehyde (MDA), glutathione (GSH) and catalase] biomarkers as well as WFS1 expression level were evaluated. HFD decreased pancreatic WFS1 protein and GSH levels, and enhanced pancreatic catalase activity, MDA content, BIP and CHOP protein and mRNA levels as well as Wfs1 mRNA amount. Accordingly, it increased BIP, CHOP and WFS1 protein levels in the extracted ER of pancreas. In addition, the HFD caused glucose intolerance, and decreased the islets' GSIS and insulin content. However, 4-PBA administration restored the alterations. It seems that, HFD consumption through inducing pancreatic ER stress, altered WFS1 expression levels, reduced the islets' GSIS and insulin content and finally impaired glucose homeostasis.


Assuntos
Proteínas de Ligação a Calmodulina , Ilhotas Pancreáticas , Proteínas de Membrana , Animais , Masculino , Ratos , Proteínas de Ligação a Calmodulina/metabolismo , Catalase/metabolismo , Dieta Hiperlipídica/efeitos adversos , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Glucose/metabolismo , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Proteínas de Membrana/metabolismo , RNA Mensageiro/metabolismo
4.
J Complement Integr Med ; 19(3): 581-589, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34533006

RESUMO

OBJECTIVES: The effects of intra-ventral hippocampal memantine administration in male NMRI stressed mice were studied. METHODS: Two stainless steel gauge 23 guide cannulas were placed in the middle part of the mice ventral hippocampus using stereotaxic coordination. Seven days later, the animals were undergone to the stress protocol as follows: They experience four consecutive electro-foot shock stress sessions lasting for 10 min. Five or 30 min before each stress session, the animals received intra-ventral hippocampal (0.1, 1 and, 5 µg/mouse) or intraperitoneal (1, 5, and 10 mg/kg) memantine respectively. Eight days after stress termination, the animals were tested either for the maintenance of either anxiety (elevated plus maze) or depression (forced swimming test). RESULTS: Animals show anxiety eight days after stress termination. Intra-ventral hippocampal infusion of memantine (5 µg/mouse) 5 min before stress inhibited the anxiety-like behaviors. However, other doses of the drug exacerbate the stress effect. The drug, when injected peripherally exacerbated the stress effect in all doses. The drug by itself had no effect. In addition, animals also show depression nine days after stress termination and memantine (0.1, 1, and 5 µg/mouse) reduced the stress effect. The drug (0.1 µg/mouse) by itself induced depression in the animals. However, the drug when injected peripherally reduced the stress effect in all doses. CONCLUSIONS: It could be concluded that NMDA glutamate receptors in the ventral hippocampus may play a pivotal role in the mediation of maintenance of anxiety and depression induced by stress in the mice.


Assuntos
Ansiolíticos , Animais , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Comportamento Animal , Hipocampo , Masculino , Memantina/farmacologia , Memantina/uso terapêutico , Camundongos , N-Metilaspartato/farmacologia , Aço Inoxidável/farmacologia
5.
J Environ Manage ; 286: 112166, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33609930

RESUMO

The people suffering from coronavirus have to lead unprecedented actions including limiting travel especially using public transportation. Therefore, lockdown measures and social distancing to decelerate the distribution of the COVID-19 has become the new norm. Nevertheless, improvement in the ambient air quality of the cities globally has appeared as a key advantage of this lockdown. There is a lack of research in the field of public transportation mobility and the Air Quality Index (AQI) during the COVID-19 lockdown globally. Consequently, this research aims to examine the overall impact of the public transit usage and ambient air quality, i.e. both AQI and indicatory air pollutants, during the lockdown in 12 countries. Data collections for analysis of public transportation usage and air quality status during the lockdown and one year before this period were carried out utilizing public transportation application Moovit and World's Air Pollution. The results demonstrated that the lockdowns of 12 countries led to dramatically decreased human movements and public transit usage up to -90% until the end of March and it had no major changes until the end of May. In the case of ambient air quality, the average values of AQI in the 12 countries within lockdown 2020 for classes I(AQI:0-50), II(AQI:51-100), and III(AQI:101-150) increased by 12%, 9%, and 13% while for classes IV(AQI:151-200), V(AQI:201-300) and VI(AQI:301-greater) decreased by 10%, 27%, and 3% in comparison with the identical time throughout 2019. The results also indicate that throughout lockdown 2020, in the 12 countries, the percentages of indicatory air pollutants of PM2.5, PM10, SO2, CO, and NO2 were decreased by 16%, 21%, 41%, 48%, and 35% lower than those in the same time in 2019. Mechanism analysis and comparisons highlighted that the lockdowns of 12 countries led to decreased human mobility and improvement in the AQI around the world.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Cidades , Controle de Doenças Transmissíveis , Monitoramento Ambiental , Humanos , Material Particulado/análise , SARS-CoV-2
6.
Physiol Behav ; 231: 113312, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33412188

RESUMO

This study assessed the effect of a chronic high-fat diet (HFD) on plasma and hippocampal insulin and corticosterone levels, the hippocampus insulin receptor amount, and spatial learning and memory with or without receiving 4-phenyl butyric acid (4-PBA) in male rats. Rats were divided into high-fat and normal diet groups, then each group was subdivided into dimethyl sulfoxide (DMSO) and 4-PBA groups. After weaning, the rats were fed with HFD for 20 weeks. Then, 4-PBA or DMSO were injected for 3 days. Subsequently, oral glucose tolerance test was done. On the following day, spatial memory tests were performed. Then the hippocampus Bip, Chop, insulin, corticosterone, and insulin receptor levels were determined. HFD increased plasma glucose, leptin and corticosterone concentrations, hippocampus Bip, Chop and corticosterone levels, food intake, abdominal fat weight and body weight along with impaired glucose tolerance. It decreased plasma insulin, and insulin content, and its receptor amount in hippocampus. HFD lengthened escape latency and shortened the duration spent in target zone. 4-PBA administration improved the HFD- induced adverse changes. Chronic HFD possibly through the induction of endoplasmic reticulum (ER) stress and subsequent changes in the levels of hippocampal corticosterone, insulin and insulin receptor along with possible leptin resistance caused spatial learning and memory deficits.


Assuntos
Dieta Hiperlipídica , Receptor de Insulina , Animais , Ácido Butírico , Dieta Hiperlipídica/efeitos adversos , Hipocampo , Insulina , Masculino , Aprendizagem em Labirinto , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Ratos , Aprendizagem Espacial
7.
Basic Clin Neurosci ; 11(3): 279-288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963721

RESUMO

INTRODUCTION: This research investigated the effects of violent and football video games on cognitive functions, cortisol levels, and brain waves. METHODS: A total of 64 participants competed in a single-elimination tournament. Saliva samples of all players were obtained before and after the games for the assessment of cortisol levels. The cognitive performances of the players were also assessed by paced auditory serial addition test. Moreover, the electroencephalogram recording was conducted during the games. RESULTS: The results showed that salivary cortisol levels significantly decreased after playing both games. Also, playing the football game increased reaction time, whereas decreased sustained attention and mental fatigue. CONCLUSION: Conversely, following playing a violent game, the reaction time decreased, and sustained attention and mental fatigue increased. Furthermore, the results of the EEG recording revealed that playing a violent game engaged more brain regions than the football game. In conclusion, playing violent game more effectively improved cognitive performances in the players than the football game.

8.
Basic Clin Neurosci ; 9(3): 177-186, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034648

RESUMO

INTRODUCTION: Video games are common cultural issues with great influence in all societies. One of the important cognitive effects of video games is on creating stress on video players. The present research objective was to study different types of stress in players based on video game styles. METHODS: A total of 80 players, aged 18 to 30 years, played four types of video games; Runner game, Excitement game, Fear game, and Puzzle game. In the beginning, the players filled in the form of personal information as well as some general and specialized information on the games. Before starting each game, the saliva samples of the players were collected to measure their level of cortisol and α-amylase. At the end of each game, the same samples were collected again. The concentrations of cortisol and α-amylase were measured using a specialized kit and an ELISA device. In addition, the variations of brain waves were recorded by an Emotiv system. Finally, the data were analyzed in SPSS and Matlab system (after and before playing video game). RESULTS: The research findings revealed that the salivary α-amylase concentration increased significantly after playing the Fear game, Runner game, and Excitement game and decreased significantly after playing the Puzzle game. Moreover, the concentration of salivary cortisol increased significantly after playing the Runner game, Excitement game, and Fear game and decreased significantly after playing the Puzzle game. The brain wave analysis also revealed that the level of stress experienced by playing Fear game was higher than the Excitement game. CONCLUSION: According to the research findings, video games can affect the stress system as well as the cognitive system of humans depending on the game style. In addition, the type and level of stress triggered in the players depend on the game style.

9.
Basic Clin Neurosci ; 6(4): 239-52, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26649162

RESUMO

INTRODUCTION: The brain glutamate neurotransmitter system and its NMDA (N-methyl-D-aspartate) receptors in the nucleus accumbens play an important role in the incidence of sensitivity and addiction. The present study examined the inhibitory effect of glutamate NMDA receptors in the nucleus accumbens in response to chronic stress. METHODS: After the unilateral and bilateral placement of cannula(e) in the nucleus accumbens, one group of the animals received different doses of intra-accumbens memantine (0.1, 0.5 and 1 µg/mouse) 5 minutes before receiving the electric shock stress at their soles (using a Communication Box) and the other group received intraperitoneal memantine (doses of 0.1, 0.5 and 1mg/kg) 30 minutes before receiving the same shock. Chronic stress increased the animals' weight, plasma corticosterone, food and water intake, but reduced their defecation rates and eating latency. RESULTS: The intraperitoneal administration of memantine increased plasma corticosterone, water intake, fecal weight, and eating latency, but had no effect on food intake or weight. The dose and site-dependent intra-accumbens administration of memantine either exacerbated the effects of stress on plasma corticosterone levels, water and food intake, or had no effect on these parameters. Furthermore, the administration of memantine had no effect on animal's weight and inhibited the effects of stress on fecal weight and eating latency. DISCUSSION: The inhibition of glutamate NMDA receptors in the nucleus accumbens can inhibit and/or exacerbate the dose and site-dependent effects of chronic stress, and gender plays a significant role in producing this effect too.

10.
Behav Neurol ; 2014: 294149, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25177106

RESUMO

BACKGROUND: Stress and its consequences are among the causes of accidents. OBJECTIVE: The effects of intraventral tegmental area (I-VTA) memantine on the plasma corticosterone and eating parameters disturbance induced by acute stress were investigated. METHODS: Male Wistar rats (W: 250-300 g) were divided into control and experiential groups, each of which received memantine either intra-VTA or peripherally. One week after bilateral cannulation, the rats received memantine (1 and 5 µg/Rat) five min before electroshock stress. The other experimental groups received memantine (1 and 5 mg/kg) intraperitoneally 30 min before stress. The control groups received saline or memantine but did not experience stress. Food and water intake and plasma corticosterone level were recorded. RESULTS: Results showed that stress decreases food intake but does not change water intake and increase in plasma corticosterone level. Intraperitoneal memantine administration slightly inhibits the stress effects on food intake. However, water intake and plasma corticosterone level were increased. Intra-VTA memantine reduces the effects of stress on corticosterone and water intake. CONCLUSION: It could be concluded that inhibition of glutamate NMDA receptors in the VTA by memantine leads to the inhibition of the eating behavior parameters and plasma corticosterone level disturbance induced by stress in rats.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Memantina/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Estresse Psicológico/fisiopatologia , Área Tegmentar Ventral/fisiologia , Animais , Corticosterona/sangue , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/fisiologia , Eletrochoque , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Antagonistas de Aminoácidos Excitatórios/farmacologia , Injeções Intraperitoneais , Masculino , Memantina/administração & dosagem , Microinjeções , Ratos , Estresse Psicológico/sangue , Área Tegmentar Ventral/efeitos dos fármacos
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