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1.
Tohoku J Exp Med ; 262(2): 115-124, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-37821386

RESUMO

Bivalirudin as an anticoagulant reduces bleeding after percutaneous coronary intervention (PCI), while its impact in elderly Chinese patients treated with PCI needs more evidence. This study aimed to compare the clinical outcomes between bivalirudin and heparin in elderly Chinese patients treated with PCI. This cohort study retrieved data of 1,286 elderly patients treated with PCI who used bivalirudin (bivalirudin group, N = 493) or heparin (heparin group, N = 793) as anticoagulants. Net adverse clinical events (NACEs) (primary endpoint), major adverse cardiac and cerebral events (MACCEs), bleeding, and major bleeding within 30 days after PCI treatment were recorded for analysis. Our study illustrated that NACEs (12.4% vs. 17.4%, P = 0.015), bleeding (6.7% vs. 12.1%, P = 0.002), and major bleeding (2.2% vs. 6.6%, P < 0.001) were fewer in bivalirudin group compared to heparin group. No difference was found in MACCEs (7.5% vs. 9.6%,P = 0.200), and incidences of all-cause mortality (P = 0.257), cardiac mortality (P = 0.504), recurrent myocardial infarction (P = 0.423), ischemia-driven revascularization (P = 0.509), and stroke (P = 0.467), between bivalirudin group and heparin group. According to univariate logistic regression analyses, bivalirudin (vs. heparin) correlated with fewer NACEs (P = 0.016), bleeding (P = 0.002), and major bleeding (P = 0.001) in elderly patients treated with PCI, but not MACCEs (P = 0.202). After adjustment, bivalirudin (vs. heparin) was an independent factor for fewer NACEs [odds ratio (OR): 0.619, P = 0.009], bleeding (OR: 0.499, P = 0.003), and major bleeding (OR: 0.342, P = 0.003) in these patients. In summary, bivalirudin achieves fewer NACEs, bleeding, and major bleeding, but not MACCEs, versus heparin in elderly patients treated with PCI, which is verified in the multivariate model.


Assuntos
Heparina , Intervenção Coronária Percutânea , Humanos , Idoso , Heparina/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Estudos de Coortes , Anticoagulantes/efeitos adversos , Hirudinas/efeitos adversos , Hemorragia , Fragmentos de Peptídeos/efeitos adversos , Fibrinolíticos/uso terapêutico , China/epidemiologia , Proteínas Recombinantes/efeitos adversos , Resultado do Tratamento
2.
Perception ; 52(9): 613-628, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37408435

RESUMO

The origin of depth in Panum's limiting case is unclear at present, so we investigated the depth perception mechanism using a triangle type of Panum's stimulus with a slant effect and clear criterion. Experiment 1 explored whether participants can correctly perceive fixation and nonfixation features using the fixation point and quick representation of stimuli, then examined whether participants' depth judgments supported double fusion or single fusion. The results of Experiment 1 showed that participants could correctly perceive the depth of fixation and nonfixation features. That is, it supported double fusion. In Experiment 2, we examined whether the depth perceived by observers comes from depth contrast. The results of Experiment 2 showed that the depth of the two features perceived after binocular fusion did not originate from the depth contrast. The findings suggest that the depth perception mechanism of Panum's limiting case is more likely to be double fusion.


Assuntos
Percepção de Profundidade , Modelos Neurológicos , Disparidade Visual , Percepção de Profundidade/fisiologia , Disparidade Visual/fisiologia , Humanos , Fixação Ocular/fisiologia , Estimulação Luminosa , Reprodutibilidade dos Testes , Masculino , Feminino , Adulto Jovem , Adulto , Análise de Variância , Sensibilidades de Contraste/fisiologia
3.
Neural Plast ; 2022: 1560748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356364

RESUMO

Purpose: Several functional magnetic resonance imaging (fMRI) studies have investigated the resting-state functional connectivity (rs-FC) changes in the primary motor cortex (M1) in patients with acute basal ganglia ischemic stroke (BGIS). However, the frequency-specific FC changes of M1 in acute BGIS patients are still unclear. Our study was aimed at exploring the altered FC of M1 in three frequency bands and the potential features as biomarkers for the identification by using a support vector machine (SVM). Methods: We included 28 acute BGIS patients and 42 healthy controls (HCs). Seed-based FC of two regions of interest (ROI, bilateral M1s) were calculated in conventional, slow-5, and slow-4 frequency bands. The abnormal voxel-wise FC values were defined as the features for SVM in different frequency bands. Results: In the ipsilesional M1, the acute BGIS patients exhibited decreased FC with the right lingual gyrus in the conventional and slow-4 frequency band. Besides, the acute BGIS patients showed increased FC with the right medial superior frontal gyrus (SFGmed) in the conventional and slow-5 frequency band and decreased FC with the left lingual gyrus in the slow-5 frequency band. In the contralesional M1, the BGIS patients showed lower FC with the right SFGmed in the conventional frequency band. The higher FC values with the right lingual gyrus and left SFGmed were detected in the slow-4 frequency band. In the slow-5 frequency band, the BGIS patients showed decreased FC with the left calcarine sulcus. SVM results showed that the combined features (slow-4+slow-5) had the highest accuracy in classification prediction of acute BGIS patients, with an area under curve (AUC) of 0.86. Conclusion: Acute BGIS patients had frequency-specific alterations in FC; SVM is a promising method for exploring these frequency-dependent FC alterations. The abnormal brain regions might be potential targets for future researchers in the rehabilitation and treatment of stroke patients.


Assuntos
AVC Isquêmico , Gânglios da Base/diagnóstico por imagem , Mapeamento Encefálico/métodos , Humanos , AVC Isquêmico/diagnóstico por imagem , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos
4.
Neural Plast ; 2022: 2219993, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36437903

RESUMO

Objective: This study is aimed at exploring alteration in motor-related effective connectivity in individuals with transient ischemic attack (TIA). Methods: A total of 48 individuals with TIA and 41 age-matched and sex-matched healthy controls (HCs) were recruited for this study. The participants were scanned using MRI, and their clinical characteristics were collected. To investigate motor-related effective connectivity differences between individuals with TIA and HCs, the bilateral primary motor cortex (M1) was used as the regions of interest (ROIs) to perform a whole-brain Granger causality analysis (GCA). Furthermore, partial correlation was used to evaluate the relationship between GCA values and the clinical characteristics of individuals with TIA. Results: Compared with HCs, individuals with TIA demonstrated alterations in the effective connectivity between M1 and widely distributed brain regions involved in motor, visual, auditory, and sensory integration. In addition, GCA values were significantly correlated with high- and low-density lipoprotein cholesterols in individuals with TIA. Conclusion: This study provides important evidence for the alteration of motor-related effective connectivity in TIA, which reflects the abnormal information flow between different brain regions. This could help further elucidate the pathological mechanisms of motor impairment in individuals with TIA and provide a new perspective for future early diagnosis and intervention for TIA.


Assuntos
Ataque Isquêmico Transitório , Córtex Motor , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Córtex Motor/diagnóstico por imagem , Encéfalo , Imageamento por Ressonância Magnética , Mapeamento Encefálico
5.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298387

RESUMO

Mental fatigue is a widely studied topic on account of its serious negative effects. But how the neural mechanism of task switching before and after mental fatigue remains a question. To this end, this study aims to use brain functional network features to explore the answer to this question. Specifically, task-state EEG signals were recorded from 20 participants. The tasks include a 400-s 2-back-task (2-BT), followed by a 6480-s of mental arithmetic task (MAT), and then a 400-s 2-BT. Network features and functional connections were extracted and analyzed based on the selected task switching states, referred to from Pre_2-BT to Pre_MAT before mental fatigue and from Post_MAT to Post_2-BT after mental fatigue. The results showed that mental fatigue has been successfully induced by long-term MAT based on the significant changes in network characteristics and the high classification accuracy of 98% obtained with Support Vector Machines (SVM) between Pre_2-BT and Post_2-BT. when the task switched from Pre_2-BT to Pre_MAT, delta and beta rhythms exhibited significant changes among all network features and the selected functional connections showed an enhanced trend. As for the task switched from Post_MAT to Post_2-BT, the network features and selected functional connectivity of beta rhythm were opposite to the trend of task switching before mental fatigue. Our findings provide new insights to understand the neural mechanism of the brain in the process of task switching and indicate that the network features and functional connections of beta rhythm can be used as neural markers for task switching before and after mental fatigue.


Assuntos
Eletroencefalografia , Fadiga Mental , Humanos , Eletroencefalografia/métodos , Encéfalo , Mapeamento Encefálico , Máquina de Vetores de Suporte
6.
Entropy (Basel) ; 24(12)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36554120

RESUMO

Driving fatigue is the main cause of traffic accidents, which seriously affects people's life and property safety. Many researchers have applied electroencephalogram (EEG) signals for driving fatigue detection to reduce negative effects. The main challenges are the practicality and accuracy of the EEG-based driving fatigue detection method when it is applied on the real road. In our previous study, we attempted to improve the practicality of fatigue detection based on the proposed non-hair-bearing (NHB) montage with fewer EEG channels, but the recognition accuracy was only 76.47% with the random forest (RF) model. In order to improve the accuracy with NHB montage, this study proposed an improved transformer architecture for one-dimensional feature vector classification based on introducing the Gated Linear Unit (GLU) in the Attention sub-block and Feed-Forward Networks (FFN) sub-block of a transformer, called GLU-Oneformer. Moreover, we constructed an NHB-EEG-based feature set, including the same EEG features (power ratio, approximate entropy, and mutual information (MI)) in our previous study, and the lateralization features of the power ratio and approximate entropy based on the strategy of brain lateralization. The results indicated that our GLU-Oneformer method significantly improved the recognition performance and achieved an accuracy of 86.97%. Our framework demonstrated that the combination of the NHB montage and the proposed GLU-Oneformer model could well support driving fatigue detection.

7.
J Headache Pain ; 22(1): 129, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34711175

RESUMO

OBJECTIVES: In this study, we aimed to investigate the spontaneous neural activity in the conventional frequency band (0.01-0.08 Hz) and two sub-frequency bands (slow-4: 0.027-0.073 Hz, and slow-5: 0.01-0.027 Hz) in tension-type headache (TTH) patients with regional homogeneity (ReHo) analyses. METHODS: Thirty-eight TTH patients and thirty-eight healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (RS-fMRI) scanning to investigate abnormal spontaneous neural activity using ReHo analysis in conventional frequency band (0.01-0.08 Hz) and two sub-frequency bands (slow-4: 0.027-0.073 Hz and slow-5: 0.01-0.027 Hz). RESULTS: In comparison with the HC group, patients with TTH exhibited ReHo increases in the right medial superior frontal gyrus in the conventional frequency band (0.01-0.08 Hz). The between group differences in the slow-5 band (0.01-0.027 Hz) highly resembled the differences in the conventional frequency band (0.01-0.08 Hz); even the voxels with increased ReHo were spatially more extensive, including the right medial superior frontal gyrus and the middle frontal gyrus. In contrast, no region showed significant between-group differences in the slow-4 band (0.027-0.073 Hz). The correlation analyses showed no correlation between the ReHo values in TTH patients and VAS scores, course of disease and number of seizures per month in conventional band (0.01-0.08 Hz), slow-4 band (0.027-0.073 Hz), as well as in slow-5 band (0.01-0.027 Hz). CONCLUSIONS: The results showed that the superior frontal gyrus and middle frontal gyrus were involved in the integration and processing of pain signals. In addition, the abnormal spontaneous neural activity in TTH patients was frequency-specific. Namely, slow-5 band (0.01-0.027 Hz) might contain additional useful information in comparison to slow-4 band (0.027-0.073 Hz). This preliminary exploration might provide an objective imaging basis for the understanding of the pathophysiological mechanism of TTH.


Assuntos
Imageamento por Ressonância Magnética , Cefaleia do Tipo Tensional , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Lobo Frontal , Humanos , Cefaleia do Tipo Tensional/diagnóstico por imagem
8.
EMBO J ; 34(23): 2885-902, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26330467

RESUMO

The Mediator complex orchestrates multiple transcription factors with the Pol II apparatus for precise transcriptional control. However, its interplay with the surrounding chromatin remains poorly understood. Here, we analyze differential histone modifications between WT and MED23(-/-) (KO) cells and identify H2B mono-ubiquitination at lysine 120 (H2Bub) as a MED23-dependent histone modification. Using tandem affinity purification and mass spectrometry, we find that MED23 associates with the RNF20/40 complex, the enzyme for H2Bub, and show that this association is critical for the recruitment of RNF20/40 to chromatin. In a cell-free system, Mediator directly and substantially increases H2Bub on recombinant chromatin through its cooperation with RNF20/40 and the PAF complex. Integrative genome-wide analyses show that MED23 depletion specifically reduces H2Bub on a subset of MED23-controlled genes. Importantly, MED23-coupled H2Bub levels are oppositely regulated during myogenesis and lung carcinogenesis. In sum, these results establish a mechanistic link between the Mediator complex and a critical chromatin modification in coordinating transcription with cell growth and differentiation.


Assuntos
Histonas/metabolismo , Complexo Mediador/metabolismo , Animais , Células Cultivadas , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Complexo Mediador/genética , Camundongos , Modelos Biológicos , Desenvolvimento Muscular/genética , Desenvolvimento Muscular/fisiologia , Ubiquitinação/genética , Ubiquitinação/fisiologia
9.
Nanomedicine ; 19: 49-57, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31028888

RESUMO

Herein, a novel nano-system IF7-ROSPCNP, which is O2-evolving and reactive oxygen species (ROS)-activable, was developed for enhancing the combination chemotherapy and photodynamic therapy (PDT). The nanoparticles composed of photosensitizers (disulfonated meso-tetraphenylporphine, TPPS2a) and catalase in the inner core, doxorubicin (DOX) in the polymeric shell and functionalized on its surface with IF7 peptide, which specially bind to annexin 1. As confirmed that the structure of IF7-ROSPCNP was able to remain intact under normal physiological conditions. After IF7-ROSPCNP was selectively entrapped by the annexin 1-positive and ROS-abundant MCF-7/ADR cells, the shell of nanoparticles was ruptured and the entrapped photosensitizers were completely released out. Under irradiation, ROS was continuously produced and the DOX, which was conjugated to the terminal of polylactic copolymer (mPEG-PLA) by a ROS-cleavable linkage, was subsequently released. With such strategy, cellular uptake of drugs was dramatically improved resulted in an enhanced cytotoxicity and anti-tumor effect on drug resistant cancer.


Assuntos
Antineoplásicos/uso terapêutico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Oxigênio/metabolismo , Fotoquimioterapia , Espécies Reativas de Oxigênio/metabolismo , Animais , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Células MCF-7 , Camundongos , Nanopartículas/ultraestrutura , Neoplasias/patologia , Poliésteres/síntese química , Poliésteres/química , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Espectroscopia de Prótons por Ressonância Magnética , Distribuição Tecidual/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos
10.
J Neurophysiol ; 119(3): 1201-1208, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29212918

RESUMO

Using behavioral measures and ERP technique, researchers discovered at least two factors could influence the final perception of depth in Panum's limiting case, which are the vertical disparity gradient and the degree of cue conflict between two- and three-dimensional shapes. Although certain event-related potential components have been proved to be sensitive to the different levels of these two factors, some methodological limitations existed in this technique. In this study, we proposed that the omega complexity of EEG signal may serve as an important supplement of the traditional event-related potential technique. We found that the trials with lower vertical gradient disparity have lower omega complexity (i.e., higher global functional connectivity) of the occipital region, especially that of the right-occipital hemisphere. Moreover, for occipital omega complexity, the trials with low-cue conflict have significantly larger omega complexity than those with medium- and high-cue conflict. It is also found that the electrodes located in the middle line of the occipital region (i.e., POz and Oz) are more crucial to the impact of different levels of cue conflict on omega complexity than the other electrodes located in the left- and right-occipital hemispheres. These evidences demonstrated that the EEG omega complexity could reflect distinct neural activities evoked by Panum's limiting case configurations, with different levels of vertical disparity gradient and cue conflict. Besides, the influence of vertical disparity gradient and cue conflict on omega complexity may be regional dependent. NEW & NOTEWORTHY The EEG omega complexity could reflect distinct neural activities evoked by Panum's limiting case configurations with different levels of vertical disparity gradient and cue conflict. The influence of vertical disparity gradient and cue conflict on omega complexity is regional dependent. The omega complexity of EEG signal can serve as an important supplement of the traditional ERP technique.


Assuntos
Sinais (Psicologia) , Percepção de Profundidade/fisiologia , Lobo Frontal/fisiologia , Lobo Occipital/fisiologia , Disparidade Visual , Adulto , Eletroencefalografia , Potenciais Evocados Visuais , Feminino , Humanos , Masculino , Estimulação Luminosa , Processamento de Sinais Assistido por Computador , Adulto Jovem
11.
J Neurophysiol ; 117(1): 275-283, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27784803

RESUMO

The ERP components and variations of spatial complexity or functional connectivity are two distinct dimensions of neurophysiological events in the visual Go/Nogo task. Extensive studies have been conducted on these two distinct dimensions; however, no study has investigated whether these two neurophysiological events are linked to each other in the visual Go/Nogo task. The relationship between spatial complexity of electroencephalographic (EEG) data, quantified by the measure omega complexity, and event-related potential (ERP) components in a visual Go/Nogo task was studied. We found that with the increase of spatial complexity level, the latencies of N1 and N2 component were shortened and the amplitudes of N1, N2, and P3 components were decreased. The anterior Go/Nogo N2 effect and the Go/Nogo P3 effect were also found to be decreased with the increase of EEG spatial complexity. In addition, the reaction times in high spatial complexity trials were significantly shorter than those of medium and low spatial complexity trials when the time interval used to estimate the EEG spatial complexity was extended to 0∼1,000 ms after stimulus onset. These results suggest that high spatial complexity may be associated with faster cognitive processing and smaller postsynaptic potentials that occur simultaneously in large numbers of cortical pyramidal cells of certain brain regions. The EEG spatial complexity is closely related with demands of certain cognitive processes and the neural processing efficiency of human brain. NEW & NOTEWORTHY: The reaction times, the latencies/amplitudes of event-related potential (ERP) components, the Go/Nogo N2 effect, and the Go/Nogo P3 effect are linked to the electroencephalographic (EEG) spatial complexity level. The EEG spatial complexity is closely related to demands of certain cognitive processes and could reflect the neural processing efficiency of human brain. Obtaining the single-trial ERP features through single-trial spatial complexity may be a more efficient approach than traditional methods.


Assuntos
Mapeamento Encefálico , Tomada de Decisões/fisiologia , Potenciais Evocados Visuais/fisiologia , Inibição Psicológica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estimulação Luminosa , Análise de Componente Principal , Tempo de Reação/fisiologia , Adulto Jovem
12.
Brain Cogn ; 114: 11-19, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28327354

RESUMO

Although Panum's limiting case has been extensively researched, only recently has it been discovered that in addition to horizontal disparity, the final perception of depth is influenced by (i) the vertical disparity gradient and (ii) the degree of cue conflict between 2D and 3D shapes. The present study examines the neural correlates of the two factors, using EEG while observers viewed several versions of stereoscopic stimuli, which depicted Panum's limiting case. In these patterns the vertical disparity gradient was varied from 0.1 to 0.6, while the degree of cue conflict was manipulated from low to high. The ERP data showed that the amplitude of the N170 component (exogenous) was modulated by the vertical disparity gradient and cue conflict. In contrast, the N270 component (endogenous) was modulated by cue conflict only. Such findings demonstrate that both factors affect the perception of depth in Panum's limiting case, but at different stages: the vertical disparity gradient at an early stage of processing (N170) and cue conflict at two stages (N170 and N270). Hence, vertical disparity gradient is related to low-level visual stimulus parameters and can modulate exogenous component, while cue conflict is related to both exogenous and endogenous components.


Assuntos
Percepção de Profundidade/fisiologia , Potenciais Evocados/fisiologia , Visão Binocular/fisiologia , Adulto , Encéfalo/fisiologia , Sinais (Psicologia) , Eletroencefalografia , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
13.
Int J Mol Sci ; 15(2): 3319-35, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24566152

RESUMO

Glutathione peroxidases (GPX) catalyze the reduction of H2O2 or organic hydroperoxides to water or corresponding alcohols using reduced glutathione, which plays an essential role in ROS (reactive oxygen species) homeostasis and stress signaling. Thellungiella salsuginea (Eutrema salsugineum), a relative of Arabidopsis thaliana, displays an extremely high level of tolerance to salt, drought, cold and oxidative stresses. The enzymatic antioxidant systems may contribute to the stress tolerance of T. salsuginea. In the present study, we aimed at understanding the roles of the antioxidant enzymes in T. salsuginea by focusing on the GPX family. We identified the eight GPX genes in T. salsuginea, and the structure of the N-terminal domains indicated their putative chloroplastic, mitochondrial and cytoplasmic location. The exon-intron organization of these genes exhibited a conserved pattern among plant GPX genes. Multiple environmental stresses and hormone response related cis-acting elements were predicted in the promoters of TsGPX genes. The gene and protein expression profiles of TsGPXs in response to high level of salinity and osmotic stresses, in leaves and roots of T. salsuginea were investigated using real-time RT-PCR and western blotting analysis. Our result showed that different members of the GPX gene family were coordinately regulated under specific environmental stress conditions, and supported the important roles of TsGPXs in salt and drought stress response in T. salsuginea.


Assuntos
Brassicaceae/enzimologia , Glutationa Peroxidase/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Sequência de Aminoácidos , Arabidopsis/enzimologia , Arabidopsis/genética , Brassicaceae/genética , Bases de Dados Genéticas , Genoma de Planta , Glutationa Peroxidase/química , Glutationa Peroxidase/classificação , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/classificação , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Transcriptoma
14.
Brain Imaging Behav ; 18(1): 19-33, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37821673

RESUMO

This study intended to investigate the frequency specific brain oscillation activity in patients with acute basal ganglia ischemic stroke (BGIS) by using the degree centrality (DC) method. A total of 34 acute BGIS patients and 44 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI) scanning. The DC values in three frequency bands (conventional band: 0.01-0.08 Hz, slow­4 band: 0.027-0.073 Hz, slow­5 band: 0.01-0.027 Hz) were calculated. A two-sample t-test was used to explore the between-group differences in the conventional frequency band. A two-way repeated-measures analysis of variance (ANOVA) was used to analyze the DC differences between groups (BGIS patients, HCs) and bands (slow­4, slow­5). Moreover, correlations between DC values and clinical indicators were performed. In conventional band, the DC value in the right middle temporal gyrus was decreased in BGIS patients compared with HCs. Significant differences of DC were observed between the two bands mainly in the bilateral cortical brain regions. Compared with the HCs, the BGIS patients showed increased DC in the right superior temporal gyrus and the left precuneus, but decreased mainly in the right inferior temporal gyrus, right inferior occipital gyrus, right precentral, and right supplementary motor area. Furthermore, the decreased DC in the right rolandic operculum in slow-4 band and the right superior temporal gyrus in slow-5 band were found by post hoc two-sample t-test of main effect of group. There was no significant correlation between DC values and clinical scales after Bonferroni correction. Our findings showed that the DC changes in BGIS patients were frequency specific. Functional abnormalities in local brain regions may help us to understand the underlying pathogenesis mechanism of brain functional reorganization of BGIS patients.


Assuntos
AVC Isquêmico , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Gânglios da Base/diagnóstico por imagem
15.
Brain Imaging Behav ; 18(2): 456-474, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38150133

RESUMO

Anxiety disorders (ADs) are a group of prevalent and destructive mental illnesses, but the current understanding of their underlying neuropathology is still unclear. Employing voxel-based morphometry (VBM), previous studies have demonstrated several common brain regions showing grey matter volume (GMV) abnormalities. However, contradictory results have been reported among these studies. Considering that different subtypes of ADs exhibit common core symptoms despite different diagnostic criteria, and previous meta-analyses have found common core GMV-altered brain regions in ADs, the present research aimed to combine the results of individual studies to identify common GMV abnormalities in ADs. Therefore, we first performed a systematic search in PubMed, Embase, and Web of Science on studies investigating GMV differences between patients with ADs and healthy controls (HCs). Then, the anisotropic effect-size signed differential mapping (AES-SDM) was applied in this meta-analysis. A total of 24 studies (including 25 data sets) were included in the current study, and 906 patients with ADs and 1003 HCs were included. Compared with the HCs, the patients with ADs showed increased GMV in the left superior parietal gyrus, right angular gyrus, left precentral gyrus, and right lingual gyrus, and decreased GMV in the bilateral insula, bilateral thalamus, left caudate, and right putamen. In conclusion, the current study has identified some abnormal GMV brain regions that are related to the pathological mechanisms of anxiety disorders. These findings could contribute to a better understanding of the underlying neuropathology of ADs.


Assuntos
Transtornos de Ansiedade , Encéfalo , Substância Cinzenta , Imageamento por Ressonância Magnética , Humanos , Transtornos de Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/patologia , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos , Tamanho do Órgão
16.
Materials (Basel) ; 16(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37629849

RESUMO

This research paper systematically investigates the combined influence of fly ash, cementitious capillary crystalline waterproofing (CCCW) materials, and polypropylene fibers on the mechanical properties and impermeability of concrete through comprehensive orthogonal tests. Microscopic morphological changes in the concrete induced by different composite materials are examined via scanning electron microscopy (SEM) and X-ray diffraction (XRD) testing. The objective is to facilitate a beneficial synergetic interaction among these materials to develop highly permeable, crack-resistant concrete. Key findings of this study are: (1) The study unveils the impact of the concentration of three additive materials on the concrete's compressive strength, tensile strength, and penetration height, thereby outlining their significant influence on the mechanical properties and impermeability of the concrete; (2) An integrated scoring method determined the optimal composite dosage of three materials: 15% fly ash, 2% CCCW, and polypropylene fibers at 1.5 kg/m3. This combination increased the concrete's compressive strength by 12.5%, tensile strength by 48.4%, and decreased the average permeability height by 63.6%; (3) The collective introduction of these three materials notably augments the hydration reaction of the cement, resulting in denser concrete microstructure, enhanced bonding between fibers and matrix, and improved concrete strength and durability.

17.
J Psychiatr Res ; 165: 325-335, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37573797

RESUMO

BACKGROUND: Recent studies using resting-state functional magnetic resonance imaging (rs-fMRI) demonstrate that there is aberrant regional spontaneous brain activity in obsessive-compulsive disorders (OCD). Nevertheless, the results of previous studies are contradictory, especially in the abnormal brain regions and the directions of their activities. It is necessary to perform a meta-analysis to identify the common pattern of altered regional spontaneous brain activity in patients with OCD. METHODS: The present study conducted a systematic search for studies in English published up to May 2023 in PubMed, Web of Science, and Embase. These studies measured differences in regional spontaneous brain activity at the whole brain level using regional homogeneity (ReHo), the amplitude of low-frequency fluctuations (ALFF) and the fractional amplitude of low-frequency fluctuations (fALFF). Then the Anisotropic effect-size version of seed-based d mapping (AES-SDM) was used to investigate the consistent abnormality of regional spontaneous brain activity in patients with OCD. RESULTS: 27 studies (33 datasets) were included with 1256 OCD patients (650 males, 606 females) and 1176 healthy controls (HCs) (588 males, 588 females). Compared to HCs, patients with OCD showed increased spontaneous brain activity in the right inferior parietal gyrus (Brodmann Area 39), left median cingulate and paracingulate gyri (Brodmann Area 24), bilateral inferior cerebellum, right middle frontal gyrus (Brodmann Area 46), left inferior frontal gyrus in triangular part (Brodmann Area 45) and left middle frontal gyrus in orbital part (Brodmann Area 11). Meanwhile, decreased spontaneous brain activity was identified in the right precentral gyrus (Brodmann Area 4), right insula (Brodmann Area 48), left postcentral gyrus (Brodmann Area 43), bilateral superior cerebellum and left caudate (Brodmann Area 25). CONCLUSIONS: This meta-analysis provided a quantitative review of spontaneous brain activity in OCD. The results demonstrated that the brain regions in the frontal lobe, sensorimotor cortex, cerebellum, caudate and insula are crucially involved in the pathophysiology of OCD. This research contributes to the understanding of the pathophysiologic mechanism underlying OCD and could provide a new perspective on future diagnosis and treatment of OCD.

18.
Materials (Basel) ; 16(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36984071

RESUMO

As a new type of pre-reinforcement material for tunnel faces, glass fiber-reinforced polymer (GFRP) bolts can effectively and safely improve the stability of tunnel faces in soft surrounding rocks and speed up excavation. Therefore, in this paper, systematic research is carried out on the bond strength of GFRP bolts in tunnel faces and their relative pre-reinforcement parameters. Firstly, the effects of rebar diameter, anchorage length, and mortar strength on the bonding properties of GFRP bars were studied by indoor pull-out tests. The bond strength-slip curves under different working conditions were obtained, and the curves showed that the ultimate bond strength between GFRP bars and mortar was negatively correlated with the diameter of GFRP bars but positively correlated with the strength of the mortar. In addition, the increase in anchorage length led to a reduction in bonding strength. Secondly, inverse analysis was used to analyse the mechanical parameters of the bond performance of the anchor bars by the finite difference software FLAC3D, and the results indicated that 1/5 of the compressive strength of the GFRP bar grouting body can be taken as the ultimate bond strength to calculate the cohesive strength of the grout. Additionally, the formula of GFRP bar grouting body stiffness was revised. Finally, based on the results of laboratory tests and the inverse analysis, the numerical simulation analysis results showed that the optimal reinforcement configuration for a shallow buried tunnel face surrounded by weak rock is to use GFRP bars with a length of 17 m arranged in the center circle of the tunnel face with a reasonable reinforcement density of 1.0 bolt/m2. The calculation formula of the stiffness and cohesion strength of the GFRP bar grouting body and the reinforcement scheme proposed in this paper can provide a reference for the construction of shallowly buried rock tunnels in soft surrounding rock.

19.
Brain Sci ; 13(3)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36979194

RESUMO

Depression has become one of the most common mental illnesses, causing serious physical and mental harm. However, there remain unclear and uniform physiological indicators to support the diagnosis of clinical depression. This study aimed to use machine learning techniques to investigate the abnormal multidimensional EEG features in patients with depression. Resting-state EEG signals were recorded from 41 patients with depression and 34 healthy controls. Multiple dimensional characteristics were extracted, including power spectral density (PSD), fuzzy entropy (FE), and phase lag index (PLI). These three different dimensional characteristics with statistical differences between two groups were ranked by three machine learning algorithms. Then, the ranked characteristics were placed into the classifiers according to the importance of features to obtain the optimal feature subset with the highest classification accuracy. The results showed that the optimal feature subset contained 86 features with the highest classification accuracy of 98.54% ± 0.21%. According to the statistics of the optimal feature subset, PLI had the largest number of features among the three categories, and the number of beta features was bigger than other rhythms. Moreover, compared to the healthy controls, the PLI values in the depression group increased in theta and beta rhythms, but decreased in alpha1 and alpha2 rhythms. The PSD of theta and beta rhythms were significantly greater in depression group than that in healthy controls, and the FE of beta rhythm showed the same trend. These findings indicate that the distribution of abnormal multidimensional features is potentially useful for the diagnosis of depression and understanding of neural mechanisms.

20.
Atten Percept Psychophys ; 85(8): 2894-2906, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37831363

RESUMO

Panum's limiting case is a phenomenon of monocular occlusion in binocular vision. This occurs when one object is occluded by the other object for one eye, but the two objects are both visible for the other eye. Although previous studies have found that vertical gradient of horizontal disparity and cue conflict are two important factors for double fusion, the effect of training on the sensitivity and stability of Panum's limiting case remains unknown. The current study trained 26 participants for 5 days with several of Panum's configurations (Gilliam, Frisby, and Wang series). The latency and duration of double fusion were recorded to examine the effects of training on sensitivity and stability of double fusion in Panum's limiting case. For each level of vertical gradient of horizontal disparity and cue conflict, the latency of double fusion decreased and the duration of double fusion increased with each additional training session. The results showed that vertical gradient of horizontal disparity and cue conflict interacted, and the duration of high cue conflict was significantly shorter than that of medium and low cue conflict for each level of vertical gradient of horizontal disparity. The findings suggest that there is an effect of training for vertical gradient of horizontal disparity and cue conflict in Panum's limiting case, and that the three factors jointly affect the sensitivity and stability of double fusion.


Assuntos
Percepção de Profundidade , Visão Binocular , Humanos , Disparidade Visual
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