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The intricate relationship between prestimulus alpha oscillations and visual contrast detection variability has been the focus of numerous studies. However, the causal impact of prestimulus alpha traveling waves on visual contrast detection remains largely unexplored. In our research, we sought to discern the causal link between prestimulus alpha traveling waves and visual contrast detection across different levels of mental fatigue. Using electroencephalography alongside a visual detection task with 30 healthy adults (13 females; 17 males), we identified a robust negative correlation between prestimulus alpha forward traveling waves (FTWs) and visual contrast threshold (VCT). Inspired by this correlation, we utilized 45/-45° phase-shifted transcranial alternating current stimulation (tACS) in a sham-controlled, double-blind, within-subject experiment with 33 healthy adults (23 females; 10 males) to directly modulate these alpha traveling waves. After the application of 45° phase-shifted tACS, we observed a substantial decrease in FTW and an increase in backward traveling waves, along with a concurrent increase in VCT, compared with the sham condition. These changes were particularly pronounced under a low fatigue state. The findings of state-dependent tACS effects reveal the potential causal role of prestimulus alpha traveling waves in visual contrast detection. Moreover, our study highlights the potential of 45/-45° phase-shifted tACS in cognitive modulation and therapeutic applications.
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Ritmo alfa , Sensibilidades de Contraste , Estimulação Transcraniana por Corrente Contínua , Humanos , Feminino , Masculino , Adulto , Ritmo alfa/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Sensibilidades de Contraste/fisiologia , Adulto Jovem , Método Duplo-Cego , Eletroencefalografia/métodos , Estimulação Luminosa/métodos , Percepção Visual/fisiologia , Fadiga Mental/fisiopatologiaRESUMO
Impairments in working memory (WM) are evident in both clinically diagnosed patients with mild cognitive decline and older adults at risk, as indicated by lower scores on neuropsychological tests. Examining the WM-related neural signatures in at-risk older adults becomes essential for timely intervention. WM functioning relies on dynamic brain activities, particularly within the frontoparietal system. However, it remains unclear whether the cognitive decline would be reflected in the decreased dynamic reconfiguration of brain coactivation states during WM tasks. We enrolled 47 older adults and assessed their cognitive function using the Montreal Cognitive Assessment. The temporal dynamics of brain coactivations during a WM task were investigated through graph-based time-frame modularity analysis. Four primary recurring states emerged: two task-positive states with positive activity in the frontoparietal system (dorsal attention and central executive); two task-negative states with positive activity in the default mode network accompanied by negative activity in the frontoparietal networks. Heightened WM load was associated with increased flexibility of the frontoparietal networks, but the cognitive decline was correlated with reduced capacity for neuroplastic changes in response to increased task demands. These findings advance our understanding of aberrant brain reconfiguration linked to cognitive decline, potentially aiding early identification of at-risk individuals.
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Disfunção Cognitiva , Memória de Curto Prazo , Humanos , Idoso , Memória de Curto Prazo/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Cognição/fisiologia , Disfunção Cognitiva/diagnóstico por imagem , Mapeamento Encefálico , Testes Neuropsicológicos , Imageamento por Ressonância MagnéticaRESUMO
Deciduous woody plants like poplar (Populus spp.) have seasonal bud dormancy. It has been challenging to simultaneously delay the onset of bud dormancy in the fall and advance bud break in the spring, as bud dormancy, and bud break were thought to be controlled by different genetic factors. Here, we demonstrate that heterologous expression of the REVEILLE1 gene (named AaRVE1) from Agave (Agave americana) not only delays the onset of bud dormancy but also accelerates bud break in poplar in field trials. AaRVE1 heterologous expression increases poplar biomass yield by 166% in the greenhouse. Furthermore, we reveal that heterologous expression of AaRVE1 increases cytokinin contents, represses multiple dormancy-related genes, and up-regulates bud break-related genes, and that AaRVE1 functions as a transcriptional repressor and regulates the activity of the DORMANCY-ASSOCIATED PROTEIN 1 (DRM1) promoter. Our findings demonstrate that AaRVE1 appears to function as a regulator of bud dormancy and bud break, which has important implications for extending the growing season of deciduous trees in frost-free temperate and subtropical regions to increase crop yield.
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Agave , Populus , Proteínas de Plantas/metabolismo , Populus/metabolismo , Estações do Ano , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Using a "core-first" approach with atom transfer radical polymerization, fluorescent center-functional star polymers of equivalent molecular weight but with varying numbers of arms (di-, tri-, and tetra-arm) were prepared. The sensitivity of fluorescence, combined with a dye-labeling technique introducing a fluorescent donor (carbazole) and an acceptor (anthracene) at the center of poly(methyl methacrylate) (PMMA) chains, enabled the application of time-resolved fluorescence resonance energy transfer to obtain quantitative insights into the conformation of the star polymer chains in the film state. When the results of star-branched polymers were compared with those of linear polymers of identical type and molecular weight, the impact of branching on polymer behavior was isolated for examination. Although the star topology does not alter the average intercoil distance, it affects the distance dispersity. Star polymers with higher arm numbers display decreased dispersity from distance due to reduced intermolecular aggregation at their geometric centers. This study presents the first spectroscopic evidence regarding the distribution of geometric centers in star polymers, offering a physical understanding of chain interpenetration and entanglement within star polymers.
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Most tough elastomer composites are reinforced by introducing sacrificial structures and fillers. Understanding the contribution of fillers and sacrificial bonds in elastomer composites to the energy dissipation is critical for the design of high-toughness materials. However, the energy dissipation mechanism in elastomer composites remains elusive. In this study, using a tearing test and time-temperature superposition, we investigate the effect of fillers and sacrificial bonds on the energy dissipation of elastomer composites consisting of poly(lipoic acid)/silver-coated Al fillers. We found that the fillers and sacrificial bonds mutually enhance both the intrinsic fracture energy and the bulk energy dissipation, and moreover the sacrificial bonds play a more important role in enhancing fracture toughness than the fillers. It is unreasonable to rely solely on the loss factor for bulk energy dissipation. The addition of sacrificial bonds results in a chain segment experiencing greater binding force compared to the addition of fillers. This suggests that the chain segment consumes more energy during its movement. By calculating the length of the Kuhn chain segment and the Kuhn number, it is evident that the addition of sacrificial bonds results in a greater binding force for the chain segment than the addition of fillers, and this enhanced binding force increases the energy consumption during the motion of the chain segment.
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INTRODUCTION: EEG microstates have been widely adopted to understand the complex and dynamic-changing process in dynamic brain systems, but how microstates are temporally modulated by emotion dynamics is still unclear. An investigation of EEG microstates under video-evoking emotion dynamics modulation would provide a novel insight into the understanding of temporal dynamics of functional brain networks. METHODS: In the present study, we postulate that emotional states dynamically modulate the microstate patterns, and perform an in-depth investigation between EEG microstates and emotion dynamics under a video-watching task. By mapping from subjective-experienced emotion states and objective-presented stimulation content to EEG microstates, we gauge the comprehensive associations among microstates, emotions, and multimedia stimulation. RESULTS: The results show that emotion dynamics could be well revealed by four EEG microstates (MS1, MS2, MS3, and MS4), where MS3 and MS4 are found to be highly correlated to different emotion states (emotion task effect and level effect) and the affective information involved in the multimedia content (visual and audio). CONCLUSION: In this work, we reveal the microstate patterns related to emotion dynamics from sensory and stimulation dimensions, which deepens the understanding of the neural representation under emotion dynamics modulation and will be beneficial for the future study of brain dynamic systems.
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Encéfalo , Eletroencefalografia , Eletroencefalografia/métodos , Encéfalo/fisiologia , Emoções , Mapeamento Encefálico/métodosRESUMO
Individual pain sensitivity is modulated by the brain's structural and functional features, but its heritability remains unclear. This paper conducted a brain-wide genome-wide association study (GWAS) to explore the genetic bases of neuroimage phenotypes of pain sensitivity. In total, 432 normal participants were divided into high and low pain sensitivity groups according to the laser quantitative test threshold. Then, the brain's gray matter density (GMD) features correlated with pain sensitivity were identified. Next, GWAS was performed on each GMD phenotype using quality-controlled genotypes. Based on the heatmap and hierarchical clustering results, the right insula was identified for further refined analysis in terms of subregions GMD and resting-state functional connectivity (rs-FC) phenotypes. The results indicate that the right insula GMD in the high sensitivity group is significantly lower than that in the low sensitivity group. Also, the TT/TC group at locus rs187974 has lower right insula GMD than the CC group. Further, loci at gene CYP2D6 may lead to a variation of rs-FC between the right insula and left putamen. In conclusion, our study suggests that the right insula and multiple candidate loci may be importantly involved in pain sensitivity modulation, which may guide the future development of precision pain therapeutics.
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Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Humanos , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Dor/genética , FenótipoRESUMO
Retinopathy of prematurity (ROP) is an important cause of avoidable childhood visual impairment, and the increase in number and survival of premature infants may inflate its burden globally. We aimed to comprehensively assess the trends and inequalities in the burden of ROP-related visual impairment and to identify improvement gaps to facilitate appropriate actions in neonatal care systems. We obtained ROP data from the Global Burden of Disease 2019 study. We employed joinpoint regression analysis to assess the trends of the burden of ROP-related visual impairment, measured by age-standardised prevalence rates, health equity analysis methods to evaluate cross-country burden inequalities, and data envelopment and stochastic frontier analyses to identify improvement gaps based on the development status, i.e., sociodemographic index (SDI). Between 1990 and 2019, the age-standardised prevalence rates of ROP-related visual impairment significantly increased worldwide (average annual percentage change: 0.23 [95% confidence interval, 0.21-0.26] among males and 0.26 [0.25-0.27] among females), primarily in developed regions. Although significant SDI-related cross-country inequalities were identified, these reduced over time (slope index of inequality: -57.74 [-66.22 to -49.25] in 1990 to -29.68 [-38.39 to -20.97] in 2019; health concentration index: -0.11 [-0.13 to -0.09] in 1990 to -0.07 [-0.09 to -0.06] in 2019). Notably, some less-developed countries exhibited superior performance despite limited resources, whereas others with a higher SDI delivered lagging performance. Conclusion: The global burden of ROP-related visual impairment has steadily increased between 1990 and 2019, with disproportionate burden concentration among less-developed countries, requiring appropriate preventive and intervention measures. What is Known: ⢠Retinopathy of prematurity (ROP) is an important cause of avoidable childhood visual impairment. ⢠The prevalence of ROP is anticipated to increase due to the growing number of extremely premature infants. What is New: ⢠The prevalence of ROP-related visual impairment has increased worldwide, primarily in developed regions, with declining but persisting cross-country inequalities. ⢠The increasing burden of ROP-related visual impairment should be considered as part of global and national health agendas, requiring interventions with proven efficacy.
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Doenças do Recém-Nascido , Retinopatia da Prematuridade , Recém-Nascido , Masculino , Lactente , Feminino , Humanos , Criança , Retinopatia da Prematuridade/complicações , Retinopatia da Prematuridade/epidemiologia , Países em Desenvolvimento , Lactente Extremamente Prematuro , Prevalência , Transtornos da Visão/epidemiologia , Transtornos da Visão/etiologia , Idade GestacionalRESUMO
PURPOSE: To evaluate the association of body stature with ocular biometrics and refraction in preschool children. METHODS: A cross-sectional, school-based study was conducted in Shenzhen, China. Preschool children aged 3 to 6 from 10 randomly-selected kindergartens were recruited. Ocular biometric parameters, including axial length (AL), anterior chamber depth (ACD), vitreous chamber depth (VCD), corneal radius curvature (CR), axial length to corneal radius ratio (AL-to-CR ratio) and lens thickness (LT) were measured using non-contact partial-coherence laser interferometry. Cycloplegic refractions were obtained by a desktop autorefractor. Body height and weight were measured using standard procedures. The association between body stature and ocular biometrics were analyzed with univariable and multivariable regression model. RESULTS: A total of 373 preschoolers were included. AL, ACD, VCD, CR, and AL-to-CR ratio, were positively associated with height and weight (p < 0.05), whereas LT was negatively associated with height and weight (p < 0.01). No association was observed between stature and central cornea thickness and refraction. After adjusted for age and gender in a multivariable regression model, AL had positive associations with height (p < 0.01) and weight (p < 0.01). However, refraction had no significant association with stature parameters. CONCLUSION: Taller and heavier preschoolers had eyes with longer AL, deeper vitreous chamber, and flatter cornea. The significant associations between body stature and ocular biometric parameters reveal the driving influence of body development on the growth of eyeballs in preschoolers.
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Segmento Anterior do Olho , Estatura , Pré-Escolar , Humanos , Estudos Transversais , Biometria , China/epidemiologiaRESUMO
Depression is a major psychological disorder with a growing impact worldwide. Traditional methods for detecting the risk of depression, predominantly reliant on psychiatric evaluations and self-assessment questionnaires, are often criticized for their inefficiency and lack of objectivity. Advancements in deep learning have paved the way for innovations in depression risk detection methods that fuse multimodal data. This paper introduces a novel framework, the Audio, Video, and Text Fusion-Three Branch Network (AVTF-TBN), designed to amalgamate auditory, visual, and textual cues for a comprehensive analysis of depression risk. Our approach encompasses three dedicated branches-Audio Branch, Video Branch, and Text Branch-each responsible for extracting salient features from the corresponding modality. These features are subsequently fused through a multimodal fusion (MMF) module, yielding a robust feature vector that feeds into a predictive modeling layer. To further our research, we devised an emotion elicitation paradigm based on two distinct tasks-reading and interviewing-implemented to gather a rich, sensor-based depression risk detection dataset. The sensory equipment, such as cameras, captures subtle facial expressions and vocal characteristics essential for our analysis. The research thoroughly investigates the data generated by varying emotional stimuli and evaluates the contribution of different tasks to emotion evocation. During the experiment, the AVTF-TBN model has the best performance when the data from the two tasks are simultaneously used for detection, where the F1 Score is 0.78, Precision is 0.76, and Recall is 0.81. Our experimental results confirm the validity of the paradigm and demonstrate the efficacy of the AVTF-TBN model in detecting depression risk, showcasing the crucial role of sensor-based data in mental health detection.
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Depressão , Humanos , Depressão/diagnóstico , Gravação em Vídeo , Emoções/fisiologia , Aprendizado Profundo , Expressão Facial , Feminino , Masculino , Adulto , Redes Neurais de ComputaçãoRESUMO
Determining and decoding emotional brain processes under ecologically valid conditions remains a key challenge in affective neuroscience. The current functional Magnetic Resonance Imaging (fMRI) based emotion decoding studies are mainly based on brief and isolated episodes of emotion induction, while sustained emotional experience in naturalistic environments that mirror daily life experiences are scarce. Here we used 12 different 10-minute movie clips as ecologically valid emotion-evoking procedures in n = 52 individuals to explore emotion-specific fMRI functional connectivity (FC) profiles on the whole-brain level at high spatial resolution (432 parcellations including cortical and subcortical structures). Employing machine-learning based decoding and cross validation procedures allowed to investigate FC profiles contributing to classification that can accurately distinguish sustained happiness and sadness and that generalize across subjects, movie clips, and parcellations. Both functional brain network-based and subnetwork-based emotion classification results suggested that emotion manifests as distributed representation of multiple networks, rather than a single functional network or subnetwork. Further, the results showed that the Visual Network (VN) and Default Mode Network (DMN) associated functional networks, especially VN-DMN, exhibited a strong contribution to emotion classification. To further estimate the temporal accumulative effect of naturalistic long-term movie-based video-evoking emotions, we divided the 10-min episode into three stages: early stimulation (1â¼200 s), middle stimulation (201â¼400 s), and late stimulation (401â¼600 s) and examined the emotion classification performance at different stimulation stages. We found that the late stimulation contributes most to the classification (accuracy=85.32%, F1-score=85.62%) compared to early and middle stimulation stages, implying that continuous exposure to emotional stimulation can lead to more intense emotions and further enhance emotion-specific distinguishable representations. The present work demonstrated that sustained happiness and sadness under naturalistic conditions are presented in emotion-specific network profiles and these expressions may play different roles in the generation and modulation of emotions. These findings elucidated the importance of network level adaptations for sustained emotional experiences during naturalistic contexts and open new venues for imaging network level contributions under naturalistic conditions.
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Encéfalo , Emoções , Humanos , Emoções/fisiologia , Encéfalo/fisiologia , Felicidade , Mapeamento Encefálico/métodos , Cabeça , Imageamento por Ressonância Magnética/métodosRESUMO
BACKGROUND: The present study aimed to investigate the changes in volatile components and metabolites of Dendrobium officinale (D. officinale) juice fermented with starter cultures containing Saccharomycopsis fibuligera and Lactobacillus paracasei at 28 â for 15 days and post-ripened at 4 â for 30 days using untargeted metabolomics of liquid chromatography-mass spectrometry (LC-MS) and headspace solid-phase microextraction-gas chromatography (HS-SPME-GC-MS) before and after fermentation. RESULTS: The results showed that the alcohol contents in the S. fibuligera group before fermentation and after fermentation were 444.806 ± 10.310 µg/mL and 510.999 ± 38.431 µg/mL, respectively. Furthermore, the alcohol content in the fermentation broth group inoculated with the co-culture of L. paracasei + S. fibuligera was 504.758 ± 77.914 µg/mL, containing a significant amount of 3-Methyl-1-butanol, Linalool, Phenylethyl alcohol, and 2-Methyl-1-propanol. Moreover, the Ethyl L (-)-lactate content was higher in the co-culture of L. paracasei + S. fibuligera group (7.718 ± 6.668 µg/mL) than in the L. paracasei (2.798 ± 0.443 µg/mL) and S. fibuligera monoculture groups (0 µg/mL). The co-culture of L. paracasei + S. fibuligera significantly promoted the metabolic production of ethyl L (-)-lactate in D. officinale juice. The differential metabolites screened after fermentation mainly included alcohols, organic acids, amino acids, nucleic acids, and their derivatives. Twenty-three metabolites, including 11 types of acids, were significantly up-regulated in the ten key metabolic pathways of the co-culture group. Furthermore, the metabolic pathways, such as pentose and glucuronate interconversions, the biosynthesis of alkaloids derived from terpenoid and polyketide, and aminobenzoate degradation were significantly up-regulated in the co-culture group. These three metabolic pathways facilitate the synthesis of bioactive substances, such as terpenoids, polyketides, and phenols, and enrich the flavor composition of D. officinale juice. CONCLUSIONS: These results demonstrate that the co-culture of L. paracasei + S. fibuligera can promote the flavor harmonization of fermented products. Therefore, this study provides a theoretical basis for analyzing the flavor of D. officinale juice and the functional investigation of fermentation metabolites.
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Dendrobium , Lacticaseibacillus paracasei , Saccharomycopsis , Saccharomycopsis/metabolismo , Terpenos , Ácidos/metabolismo , Lactatos/metabolismo , FermentaçãoRESUMO
PURPOSE: Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a novel class of glucose-lowering agents that have improved clinical outcomes in patients with heart failure; however, their therapeutic mechanisms remain elusive. Although contradictory results have been reported, it has been proposed that improving Na+ homeostasis may be the underlying mechanism of action of SGLT2 inhibitors in heart failure treatment. This study explored whether empagliflozin ameliorates Na+ and Ca2+ handling disorders induced by ouabain in an Na+-dependent manner. METHODS: Isolated ventricular myocytes of mice were incubated with ouabain to establish a cellular model of Na+ overload. Effects of empagliflozin on Na+ and Ca2+ handling were evaluated using an ionOptix system and a confocal microscope. Distinct cytosolic Na+ levels were established by incubating different ouabain concentrations (10, 50, and 100 µmol/L). RESULTS: In the absence of ouabain, 1 µmol/L empagliflozin had a negligible impact on Na+ and Ca2+ handling in ventricular myocytes. Ouabain (50 µmol/L) significantly enhanced cytosolic Na+ levels and dysregulated Ca2+ handling, including an increased Ca2+ transient amplitude, elevated Ca2+ content in the sarcoplasmic reticulum, and enhanced spontaneous Ca2+ release normalized by treatment with 1 µmol/L empagliflozin within 10 min. All Na+ and Ca2+ handling abnormalities induced by ouabain were reversed by 1 µmol/L empagliflozin. The efficacy of empagliflozin was more potent at higher cytosolic Na+ levels. Pretreatment with the Na+/H+ exchanger (NHE) inhibitor (1 µmol/L cariporide) abolished the effects of empagliflozin. CONCLUSION: Empagliflozin ameliorates ouabain-induced Na+ and Ca2+ handling disorders in a cytosolic Na+-dependent manner, potentially by inhibiting the NHE.
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Insuficiência Cardíaca , Ouabaína , Camundongos , Animais , Ouabaína/farmacologia , Miócitos Cardíacos , Sódio/farmacologia , Glucose/farmacologia , Cálcio/farmacologiaRESUMO
BACKGROUND & AIMS: The individual effect of working schedule on survival in the hypertensive population has not been adequately studied. Shiftworkers are also prone to unhealthy lifestyles like pro-inflammatory diet. Therefore, we assessed the effect of shift work and its joint association with dietary inflammatory potential on mortality risk among the large US nationally representative sample of adult hypertensive population. METHODS: Data were from a nationally representative prospective cohort among US hypertensive population (n = 3680; weighted population, 54,192,988). The participants were linked to the 2019 public-access linked mortality archives. The working schedule were self-reported using the Occupation Questionnaire Section. Dietary inflammatory index (DII) scores were equally calculated using the 24-hour dietary recall (24 h) interviews. Multivariable Cox proportional hazards regression models were used to estimate hazard ratio and 95% confidence intervals (95%CI) for survival of hypertension individuals by work schedule and dietary inflammatory potential. The joint effect of work schedule and dietary inflammatory potential was then examined. RESULTS: Among the 3680 hypertension individuals (39.89% female [n = 1479] and 71.42% white [n = 1707]; weighted mean [SE] age, 47.35 [0.32] years), 592 individuals reported shift work status. 474 (10.76%) reported shift work status with pro-inflammatory dietary pattern (DII scores > 0). 118 (3.06%) reported shift work status with anti-inflammatory dietary pattern (DII scores < 0). 646 (19.64%) reported a non-shift working schedule with anti-inflammatory dietary pattern, while 2442 (66.54%) reported non-shift working schedule with pro-inflammatory dietary pattern. After a median follow-up of 11.67 years (140 months), 317 deaths (cardiovascular diseases (CVD), 65; cancer, 104) were registered. Cox regression analysis showed that shift work was associated with higher risk of all-cause mortality (hazard ratio [HR], 1.48; 95% CI, 1.07-2.06) compared with non-shift workers. In the joint analysis, shift work status combined with pro-inflammatory dietary pattern was associated with the highest all-cause mortality risk. Moreover, adopting the anti-inflammatory diet significantly attenuates the deleterious effect of shift work on mortality risk. CONCLUSIONS: In this large representative sample of adults with hypertension in the U.S., the combination of shift work status with pro-inflammatory dietary pattern was highly prevalent and was associated with the highest risks of death from all causes.
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Doenças Cardiovasculares , Hipertensão , Jornada de Trabalho em Turnos , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Fatores de Risco , Inflamação , Estudos Prospectivos , Dieta , Hipertensão/epidemiologia , Hipertensão/complicaçõesRESUMO
Aging is a universal property of multicellular organisms. Although some tree species can live for centuries or millennia, the molecular and metabolic mechanisms underlying their longevity are unclear. To address this, we investigated age-related changes in the vascular cambium from 15- to 667-y-old Ginkgo biloba trees. The ring width decreased sharply during the first 100 to 200 y, with only a slight change after 200 y of age, accompanied by decreasing numbers of cambial cell layers. In contrast, average basal area increment (BAI) continuously increased with aging, showing that the lateral meristem can retain indeterminacy in old trees. The indole-3-acetic acid (IAA) concentration in cambial cells decreased with age, whereas the content of abscisic acid (ABA) increased significantly. In addition, cell division-, cell expansion-, and differentiation-related genes exhibited significantly lower expression in old trees, especially miR166 and HD-ZIP III interaction networks involved in cambial activity. Disease resistance-associated genes retained high expression in old trees, along with genes associated with synthesis of preformed protective secondary metabolites. Comprehensive evaluation of the expression of genes related to autophagy, senescence, and age-related miRNAs, together with analysis of leaf photosynthetic efficiencies and seed germination rates, demonstrated that the old trees are still in a healthy, mature state, and senescence is not manifested at the whole-plant level. Taken together, our results reveal that long-lived trees have evolved compensatory mechanisms to maintain a balance between growth and aging processes. This involves continued cambial divisions, high expression of resistance-associated genes, and continued synthetic capacity of preformed protective secondary metabolites.
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Câmbio/metabolismo , Ginkgo biloba/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Ácido Abscísico/metabolismo , Câmbio/citologia , Ginkgo biloba/genética , Ginkgo biloba/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/biossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Tempo , Árvores/genética , Árvores/metabolismoRESUMO
The dominant approach in investigating the individual reliability for event-related potentials (ERPs) is to extract peak-related features at electrodes showing the strongest group effects. Such a peak-based approach implicitly assumes ERP components showing a stronger group effect are also more reliable, but this assumption has not been substantially validated and few studies have investigated the reliability of ERPs beyond peaks. In this study, we performed a rigorous evaluation of the test-retest reliability of ERPs collected in a multisensory and cognitive experiment from 82 healthy adolescents, each having two sessions. By comparing group effects and individual reliability, we found that a stronger group-level response in ERPs did not guarantee higher reliability. A perspective of neural oscillation should be adopted for the analysis of reliability. Further, by simulating ERPs with an oscillation-based computational model, we found that the consistency between group-level ERP responses and individual reliability was modulated by inter-subject latency jitter and inter-trial variability. The current findings suggest that the conventional peak-based approach may underestimate the individual reliability in ERPs and a neural oscillation perspective on ERP reliability should be considered. Hence, a comprehensive evaluation of the reliability of ERP measurements should be considered in individual-level neurophysiological trait evaluation and psychiatric disorder diagnosis.
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Simulação por Computador , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados Visuais/fisiologia , Vias Visuais/fisiologia , Eletrodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Adulto JovemRESUMO
EEG signals exhibit commonality and variability across subjects, sessions, and tasks. But most existing EEG studies focus on mean group effects (commonality) by averaging signals over trials and subjects. The substantial intra- and inter-subject variability of EEG have often been overlooked. The recently significant technological advances in machine learning, especially deep learning, have brought technological innovations to EEG signal application in many aspects, but there are still great challenges in cross-session, cross-task, and cross-subject EEG decoding. In this work, an EEG-based biometric competition based on a large-scale M3CV (A Multi-subject, Multi-session, and Multi-task Database for investigation of EEG Commonality and Variability) database was launched to better characterize and harness the intra- and inter-subject variability and promote the development of machine learning algorithm in this field. In the M3CV database, EEG signals were recorded from 106 subjects, of which 95 subjects repeated two sessions of the experiments on different days. The whole experiment consisted of 6 paradigms, including resting-state, transient-state sensory, steady-state sensory, cognitive oddball, motor execution, and steady-state sensory with selective attention with 14 types of EEG signals, 120000 epochs. Two learning tasks (identification and verification), performance metrics, and baseline methods were introduced in the competition. In general, the proposed M3CV dataset and the EEG-based biometric competition aim to provide the opportunity to develop advanced machine learning algorithms for achieving an in-depth understanding of the commonality and variability of EEG signals across subjects, sessions, and tasks.
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Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Algoritmos , Aprendizado de Máquina , Bases de Dados FactuaisRESUMO
Previous functional magnetic resonance imaging (fMRI) studies have shown that brain responses to nociceptive pain, non-nociceptive somatosensory, visual, and auditory stimuli are extremely similar. Actually, perception of external sensory stimulation requires complex interactions among distributed cortical and subcortical brain regions. However, the interactions among these regions elicited by nociceptive pain remain unclear, which limits our understanding of mechanisms of pain from a brain network perspective. Task fMRI data were collected with a random sequence of intermixed stimuli of four sensory modalities in 80 healthy subjects. Whole-brain psychophysiological interaction analysis was performed to identify task-modulated functional connectivity (FC) patterns for each modality. Task-modulated FC strength and graph-theoretical-based network properties were compared among the four modalities. Lastly, we performed across-sensory-modality prediction analysis based on the whole-brain task-modulated FC patterns to confirm the specific relationship between brain patterns and sensory modalities. For each sensory modality, task-modulated FC patterns were distributed over widespread brain regions beyond those typically activated or deactivated during the stimulation. As compared with the other three sensory modalities, nociceptive stimulation exhibited significantly different patterns (more widespread and stronger FC within the cingulo-opercular network, between cingulo-opercular and sensorimotor networks, between cingulo-opercular and emotional networks, and between default mode and emotional networks) and global property (smaller modularity). Further, a cross-sensory-modality prediction analysis found that task-modulated FC patterns could predict sensory modality at the subject level successfully. Collectively, these results demonstrated that the whole-brain task-modulated FC is preferentially modulated by pain, thus providing new insights into the neural mechanisms of pain processing.
Assuntos
Encéfalo/fisiologia , Conectoma , Rede Nervosa/fisiologia , Dor Nociceptiva/fisiopatologia , Percepção/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Percepção Auditiva/fisiologia , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Nociceptividade/fisiologia , Dor Nociceptiva/diagnóstico por imagem , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto JovemRESUMO
Background: There exist sex differences in the clinical profile, management, and outcome of atrial fibrillation (AF). Catheter ablation of AF has become a first-line therapy and has markedly made headway over the recent decades. Little is known about sex differences and temporal trends in hospitalization for catheter ablation of AF in the real-world setting. Methods: We retrospectively retrieved medical records of patients at Beijing Anzhen Hospital between January 2005 and December 2019. The patients undergoing catheter ablation of AF were enrolled. Demographical and clinical data were compared between sexes. The temporal trends of sex differences were evaluated. Results: We identified 13502 male patients (66.8%) and 6713 female patients (33.2%). The number of patients undergoing AF ablation had remarkably increased over time, but no sex differences were observed (p=0.17). The median age of women was five years older than that of men (p < 0.001). The median time of in-hospital stay for the women decreased from 11 days to 4 days and for the men from 9 to 4 days. In-hospital mortality was 0.03% and 0.01% for women and men, respectively, with no significant difference between sexes. The women were more likely to have a comorbid diagnosis of hypertension and heart failure than men (p < 0.001). The CHA2DS2-VA score was higher in women than in men (1.64 vs. 1.28, p < 0.001). The temporal trend in the score increased in women from 1.17 to 1.81 (p < 0.001) and in men from 0.91 to 1.41 (p < 0.001). The percentage of patients with CHA2DS2-VA score ≥2 was higher in women than in men (49.8% vs. 35.8%, p < 0.001), and the temporal trend of this sex gap was nearly doubled (8.0% in 2005-2007 vs. 15.5% in 2017-2019, p=0.03). Conclusions: Safety of catheter ablation for AF was comparable in both sexes. In contrast, the women showed a higher CHA2DS2-VA score than men. The percentage of patients with CHA2DS2-VA score ≥2 increased more quickly in women than in men. Furthermore, sex-specific research is warranted to reduce this sex disparity.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/cirurgia , Pré-Escolar , Feminino , Hospitalização , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Resultado do TratamentoRESUMO
PURPOSE: This study aimed to investigate the association between first-trimester subchorionic hematoma (SCH) detected at 6-8 weeks of gestation after fresh embryo transfers and adverse pregnancy outcomes. METHODS: We performed a retrospective cohort involving 3074 patients. All of them acquired singleton pregnancies after fresh embryo transfers in the first in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles. According to first-trimester ultrasound examinations at 6-8 weeks of gestation, we divided patients into SCH and non-SCH groups and compared their perinatal outcomes. Symptomatic patients with vaginal bleeding and asymptomatic patients were analyzed separately, and propensity score matching (PSM) and multivariable regression were adopted to control potential confounding factors. RESULTS: The incidence of SCH was 17.1% in 3074 women, and vaginal bleeding occurred in 92 SCH patients and 215 control patients. In the asymptomatic cohort, 415 women with SCH and 807 women without SCH were finally included after PSM. No significant differences were observed in livebirth rate (91.3% vs 92.9%, P = 0.314), miscarriage rate (8.4% vs 6.7%, P = 0.267), and preterm birth rate (4.8% vs 5.7%, P = 0.519) between two groups. Secondary outcomes including gestational hypertension or preeclampsia, gestational diabetes mellitus (GDM), gestational age (GA) at delivery, mode of delivery, sex of newborns and birthweight of newborns were comparable. For symptomatic patients, both univariable and multivariable regression analysis showed no significant association between SCH and pregnancy outcomes. A subgroup analysis including patients with SCH illustrated the symptom of vaginal bleeding rather than hematoma size was associated with livebirth. CONCLUSION: First-trimester SCH detected at 6-8 weeks of gestation was not associated with adverse pregnancy outcomes in singleton pregnancies after fresh embryo transfers. Vaginal bleeding was the risk factor of pregnancy loss for patients with SCH.