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1.
Article de Anglais | MEDLINE | ID: mdl-38082701

RÉSUMÉ

Situational awareness (SA) is vital for understanding our surroundings. Multiple variables, including inattentive blindness (IB), contribute to the deterioration of SA, which may have detrimental effects on individuals' cognitive performance. IB occurs due to attentional limitations, ignoring critical information and resulting in a loss of SA and a decline in general performance, particularly in complicated situations requiring substantial cognitive resources. To the best of our knowledge, however, past research has not fully uncovered the neurological characteristics of IB nor classified these characteristics in life-alike virtual situations. Therefore, the purpose of this study is to determine whether ERP dynamics in the brain may be utilised as a neural feature to predict the occurrence of IB using machine learning (ML) algorithms. In a virtual reality simulation of an IB experiment, 30 participants' behaviour and Electroencephalography (EEG) measurements were obtained. Participants were given a target detection task in the IB experiment without knowing the unattended shapes displayed on the background building. The targets were presented in three different sensory modalities (auditory, visual, and visual-auditory). On the post-experiment questionnaire, participants who claimed not to have noticed the unattended shapes were assigned to the IB group. Subsequently, the Aware group was formed from individuals who reported seeing the unattended shapes. Using EEGNet to classify IB and Aware groups demonstrated a high classification performance. According to the research, ERP brain dynamics are associated with the awareness of unattended shapes and have the potential to serve as a reliable indication for predicting the visual consciousness of unexpected objects.(p/)(p)Clinical relevance- This research offers a potential brain marker for the mixed-reality and BCI systems that will be used in the future to identify cognitive deterioration, maintain attentional capacity, and prevent disasters.


Sujet(s)
Attention , Encéphale , Humains , Cognition , Potentiels évoqués , Cécité
2.
J Hazard Mater ; 445: 130396, 2023 03 05.
Article de Anglais | MEDLINE | ID: mdl-36436455

RÉSUMÉ

The persistent organic pollutant perfluorooctanoic acid (PFOA) is ubiquitous in aquatic environments. However, little is known about its toxicity to microalgae or the mechanisms by which they may self-adapt to it. We found that growth of the bloom-forming cyanobacterium Microcystis aeruginosa was initially inhibited, with inhibition attenuated after 12 d of PFOA exposure. Growth inhibition gradually decreased and stabilized over time. With increasing PFOA concentration, reactive oxygen species levels and superoxide dismutase and photosystem II activity significantly increased, while respiration, NDH-1 activity, and total carbohydrate content significantly decreased. Self-adaptation mechanisms included antioxidant pathways, energy transfer and distribution of photosystems, and repair of the PSI and NDH complexes. The patterns of change in these parameters were consistent with those of the expression levels of genes in their associated metabolic pathways. Our data suggest that PSII overcompensation might be a strategy by which M. aeruginosa contends with oxidative stress induced by PFOA. Multiple downstream photosynthesis-related proteins were upregulated as a function of PFOA exposure time. These findings may help elucidate physiological, genetic stress and self-adaptive responses of microalgae to PFOA exposure.


Sujet(s)
Cyanobactéries , Microcystis , Photosynthèse , Stress oxydatif , Cyanobactéries/métabolisme
3.
Appl Environ Microbiol ; 88(19): e0091222, 2022 10 11.
Article de Anglais | MEDLINE | ID: mdl-36098535

RÉSUMÉ

Metal corrosion caused by Aspergillus sp. was shown to be significantly enhanced on a space station, but its mechanism is still unknown. To simulate this on earth, the corrosion capability of A. carbonarius on five metal sheets was investigated under simulated microgravity. Also, the effect of metal ions on growth and organic acid production was determined. Results showed that A. carbonarius could corrode all five types of metal, including Ti alloy, aluminum alloy, iron, and aluminum and copper sheet, and the corrosion was intensified under simulated microgravity. Energy dispersive X-ray spectrometry (EDS) analysis showed that metal ions enriched on A. carbonarius spores, especially iron, aluminum ions, and copper ions, indicating that A. carbonarius can use these metal ions. In particular, the content of oxalic acid was significantly increased after A. carbonarius cocultured with five metal materials under simulated microgravity. Al3+, Fe3+, and Cu2+ at the concentration of 0.3 mg/mL and Mg2+ at 0.8 mg/mL significantly promoted the growth and oxalic acid and citric acid production of A. carbonarius and A. niger under normal gravity and simulated microgravity. Comparing the impact of metal ions and metal sheets on the production of organic acids, it can be inferred that oxalic acid may dominate in the corrosion process of A. carbonarius. In summary, molds promoted metal corrosion by producing organic acids, and the released metal ions will further promote the growth of mold and the accumulation of organic acids. This may be an important reason for the intensification of mold corrosion under microgravity. IMPORTANCE The space station and other long-term manned spacecrafts will experience the risk of microbial corrosion, especially mold, which will be harmful to the platform system and astronauts. Aspergillus sp. has been widely reported to produce organic acids that corrode and destroy materials, and the ability of these crafts to fly through space can be significantly affected. Research on the mechanism that causes enhanced corrosion ability of fungi in space stations is important to control their growth. Our research focuses on the interaction between mold and metals. In particular, it is found that metal ions promote mold growth and produce organic acids, thus accelerating mold corrosion of metals. Our results provide a new perspective for the control of fungal corrosion under simulated microgravity.


Sujet(s)
Alliages , Impesanteur , Acides , Alliages/composition chimique , Aluminium , Aspergillus , Acide citrique , Cuivre , Corrosion , Champignons , Fer , Oxalates
4.
Prog Neurobiol ; 205: 102127, 2021 10.
Article de Anglais | MEDLINE | ID: mdl-34343631

RÉSUMÉ

Upon awakening from nighttime sleep, the stress hormone cortisol in humans exhibits a robust rise within thirty to forty-five minutes. This cortisol awakening response (CAR), a crucial point of reference within the healthy cortisol circadian rhythm, has been linked to various psychological, psychiatric and health-related conditions. The CAR is thought to prepare the brain for anticipated challenges of the upcoming day to maintain one's homeostasis and promote adaptive responses. Using brain imaging with a prospective design and pharmacological manipulation, we investigate the neurobiological mechanisms underlying this preparation function of the CAR across two studies. In Study 1, a robust CAR is predictive of less hippocampal and prefrontal activity, though enhanced functional coupling between those regions during a demanding task hours later in the afternoon. Reduced prefrontal activity is in turn linked to better working memory performance, implicating that the CAR proactively promotes brain preparedness based on improved neurocognitive efficiency. In Study 2, pharmacologically suppressed CAR using Dexamethasone mirrors this proactive effect, which further causes a selective reduction of prefrontal top-down functional modulation over hippocampal activity. These findings establish a causal link between the CAR and its proactive role in optimizing functional brain networks involved in neuroendocrine control, executive function and memory.


Sujet(s)
Hippocampe , Vigilance , Encéphale , Humains , Hydrocortisone , Études prospectives , Salive
5.
Psychoneuroendocrinology ; 103: 96-103, 2019 05.
Article de Anglais | MEDLINE | ID: mdl-30665044

RÉSUMÉ

Socioeconomic status (SES) disparities have profound impacts on child development and health, which are linked to negative emotions and alterations in the integrity of stress-sensitive hypothalamus-pituitary-adrenal (HPA)-axis system. However, its underlying psychophysiological mechanisms remain poorly understood. Here we investigate how family SES, in concert with parental anxiety, affects children's anxiety and their integrity of HPA-axis system in two studies involving a total of 1318 children and their parents. In Study 1 with a cohort of 1088 children and their parents, we found that low-SES children relative to high-SES ones experienced a higher level of anxiety mediated by increasing parental anxiety. In Study 2 with an independent cohort of 230 children and their parents, we found that low-SES children exhibited an increase in pre-bedtime basal cortisol but a decrease in cortisol awakening response (CAR). Structural equation modeling (SEM) further revealed that the association between low SES and children's reduced CAR was mediated by increased parental and child anxiety. Our findings suggest that low-SES children are more vulnerable to anxiety and altered HPA-axis integrity, most likely mediated through increased parental anxiety.


Sujet(s)
Anxiété/physiopathologie , Classe sociale , Stress psychologique/psychologie , Adolescent , Anxiété/étiologie , Anxiété/métabolisme , Troubles anxieux/métabolisme , Troubles anxieux/physiopathologie , Enfant , Rythme circadien , Études de cohortes , Famille/psychologie , Femelle , Humains , Hydrocortisone/analyse , Axe hypothalamohypophysaire/physiologie , Mâle , Parents/psychologie , Axe hypophyso-surrénalien/physiologie , Salive/composition chimique
6.
Anticancer Drugs ; 28(6): 603-612, 2017 07.
Article de Anglais | MEDLINE | ID: mdl-28422767

RÉSUMÉ

Pseudolaric acid B (PAB) is the most active constituent extracted from the bark of Pseudolarix kaempferi, which has been used as an antifungal remedy in traditional Chinese medicine. It is reported to have cytotoxicity to many tumor cell lines. In this study, we investigated the effects of PAB against human endometrial cancer Ishikawa cells. We found that PAB inhibited Ishikawa cell proliferation, and induced cell apoptosis and G2/M phase arrest through a mechanism involving AKT-GSK-3ß and ERK1/2 signaling pathways. PAB also suppressed the Ishikawa cell adhesion, invasion, migration, and colony formation ability by increasing the expression of E-cadherin, Ezrin, and Kiss-1, and decreasing the expression of matrix metalloproteinase-9 and vascular endothelial growth factor. Taken together, these data indicated that PAB can be expected to be a novel treatment agent for endometrial cancer therapy.


Sujet(s)
Apoptose/effets des médicaments et des substances chimiques , Diterpènes/pharmacologie , Tumeurs de l'endomètre/traitement médicamenteux , Tumeurs de l'endomètre/enzymologie , Système de signalisation des MAP kinases/effets des médicaments et des substances chimiques , Adhérence cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Tumeurs de l'endomètre/anatomopathologie , Femelle , Points de contrôle de la phase G2 du cycle cellulaire/effets des médicaments et des substances chimiques , Glycogen synthase kinase 3 beta/métabolisme , Humains , Points de contrôle de la phase M du cycle cellulaire/effets des médicaments et des substances chimiques , Mitogen-Activated Protein Kinase 1/métabolisme , Mitogen-Activated Protein Kinase 3/métabolisme , Métastase tumorale , Phosphatidylinositol 3-kinases/métabolisme , Protéines proto-oncogènes c-akt/métabolisme
7.
Exp Cell Res ; 352(1): 34-44, 2017 03 01.
Article de Anglais | MEDLINE | ID: mdl-28132880

RÉSUMÉ

Pseudolaric acid B (PAB) is the major bioactive constituent in the root bark of Pseudolarix kaempferi and has been reported to have cytotoxicity against tumor cells. Our in vivo experiments showed that PAB could inhibit gastric cancer cell lung metastasis in a nude mouse haematogenous dissemination model. To evaluate the anti-metastasis mechanism of PAB in gastric cancer cells, cytological experiments were performed. The results showed that PAB could inhibit the adhesion ability to matrigel, migration, invasion and colony formation ability of BGC-823 and MKN-45 cells. Western blot further confirmed that the inhibitory effects of PAB on anti-metastasis may involve regulating the expression of the metastasis-related proteins MMP-9, HIF-1α, VEGF, VEGFR2, E-Cadherin and Ezrin. We obtained further proof that PAB which could be used as a multi-targeted agent to inhibit the PI3K/AKT, ERK1/2 and mitochondria-mediated apoptosis pathways and consequently suppress tumor growth and metastasis. Our experiments suggest that PAB-induced effects may have novel therapeutic applications for the treatment of gastric cancer.


Sujet(s)
Apoptose/effets des médicaments et des substances chimiques , Diterpènes/pharmacologie , Tumeurs du poumon/prévention et contrôle , Mitochondries/effets des médicaments et des substances chimiques , Mitogen-Activated Protein Kinase 1/métabolisme , Mitogen-Activated Protein Kinase 3/métabolisme , Phosphatidylinositol 3-kinases/métabolisme , Protéines proto-oncogènes c-akt/métabolisme , Tumeurs de l'estomac/prévention et contrôle , Animaux , Technique de Western , Mouvement cellulaire , Prolifération cellulaire , Humains , Techniques in vitro , Tumeurs du poumon/métabolisme , Tumeurs du poumon/secondaire , Mâle , Souris , Souris de lignée BALB C , Souris nude , Mitochondries/métabolisme , Mitogen-Activated Protein Kinase 1/génétique , Mitogen-Activated Protein Kinase 3/génétique , Phosphatidylinositol 3-kinases/génétique , Protéines proto-oncogènes c-akt/génétique , ARN messager/génétique , Réaction de polymérisation en chaine en temps réel , RT-PCR , Tumeurs de l'estomac/métabolisme , Tumeurs de l'estomac/anatomopathologie , Cellules cancéreuses en culture , Tests d'activité antitumorale sur modèle de xénogreffe
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