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1.
Water Res ; 257: 121695, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38723352

RESUMEN

Wolframite (FeWO4), a typical polyoxometalate, serves as an auspicious candidate for heterogeneous catalysts, courtesy of its high chemical stability and electronic properties. However, the electron-deficient surface-active Fe species in FeWO4 are insufficient to cleave H2O2 via Fe redox-mediated Fenton-like catalytic reaction. Herein, we doped Sulfur (S) atom into FeWO4 catalysts to refine the electronic structure of FeWO4 for H2O2 activation and sulfamethoxazole (SMX) degradation. Furthermore, spin-state reconstruction on S-doped FeWO4 was found to effectively refine the electronic structure of Fe in the d orbital, thereby enhancing H2O2 activation. S doping also accelerated electron transfer during the conversion of sulfur species, promoting the cycling of Fe(III) to Fe(II). Consequently, S-doped FeWO4 bolstered the Fenton-like reaction by nearly two orders of magnitude compared to FeWO4. Significantly, the developed S-doped FeWO4 exhibited a remarkable removal efficiency of approximately 100% for SMX within 40 min in real water samples. This underscores its extensive pH adaptability, robust catalytic stability, and leaching resistance. The matrix effects of water constituents on the performance of S-doped FeWO4 were also investigated, and the results showed that a certain amount of Cl-, SO42-, NO3-, HCO3- and PO43- exhibited negligible effects on the degradation of SMX. Theoretical calculations corroborate that the distinctive spin-state reconstruction of Fe center in S-doped FeWO4 is advantageous for H2O2 decomposition. This discovery offers novel mechanistic insight into the enhanced catalytic activity of S doping in Fenton-like reactions and paves the way for expanding the application of FeWO4 in wastewater treatment.

2.
J Org Chem ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38757188

RESUMEN

A base-assisted dearomative [2 + 1] spiroannulation of p/o-bromophenols with activated olefins (methylenemalonates) to construct various cyclopropyl spirocyclohexadienone skeletons is reported. Furthermore, several other halophenols (X = Cl, I) were also tolerated in this process. Control experiments reveal a dearomative Michael addition of phenols at their halogenated positions to methylenemalonates, followed by intramolecular radical-based SRN1 dehalogenative cyclopropanation. However, according to the density functional theory (DFT) calculations, an SN2 dehalogenative cyclopropanation with the same low activation energy barrier should not be excluded. The utility of this method is showcased by gram-scale syntheses and transformations of the dearomatized products.

3.
Neural Plast ; 2024: 8862647, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38715980

RESUMEN

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder that is characterized by inattention, hyperactivity, and impulsivity. The neural mechanisms underlying ADHD remain inadequately understood, and current approaches do not well link neural networks and attention networks within brain networks. Our objective is to investigate the neural mechanisms related to attention and explore neuroimaging biological tags that can be generalized within the attention networks. In this paper, we utilized resting-state functional magnetic resonance imaging data to examine the differential functional connectivity network between ADHD and typically developing individuals. We employed a graph convolutional neural network model to identify individuals with ADHD. After classification, we visualized brain regions with significant contributions to the classification results. Our results suggest that the frontal, temporal, parietal, and cerebellar regions are likely the primary areas of dysfunction in individuals with ADHD. We also explored the relationship between regions of interest and attention networks, as well as the connection between crucial nodes and the distribution of positively and negatively correlated connections. This analysis allowed us to pinpoint the most discriminative brain regions, including the right orbitofrontal gyrus, the left rectus gyrus and bilateral insula, the right inferior temporal gyrus and bilateral transverse temporal gyrus in the temporal region, and the lingual gyrus of the occipital lobe, multiple regions of the basal ganglia and the upper cerebellum. These regions are primarily involved in the attention executive control network and the attention orientation network. Dysfunction in the functional connectivity of these regions may contribute to the underlying causes of ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Encéfalo , Imagen por Resonancia Magnética , Redes Neurales de la Computación , Humanos , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Masculino , Femenino , Encéfalo/fisiopatología , Encéfalo/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Adulto , Mapeo Encefálico/métodos , Vías Nerviosas/fisiopatología , Vías Nerviosas/diagnóstico por imagen , Adulto Joven , Adolescente , Niño , Atención/fisiología
4.
Nat Chem ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719944

RESUMEN

Chiral sulfur pharmacophores are crucial for drug discovery in bioscience and medicinal chemistry. While the catalytic asymmetric synthesis of sulfoxides and sulfinate esters with stereogenic-at-sulfur(IV) centres is well developed, the synthesis of chiral sulfinamides remains challenging, which has primarily been attributed to the high nucleophilicity and competing reactions of amines. In this study, we have developed an efficient methodology for the catalytic asymmetric synthesis of chiral sulfinamides and sulfinate esters by the sulfinylation of diverse nucleophiles, including aromatic amines and alcohols, using our bifunctional chiral 4-arylpyridine N-oxides as catalysts. The remarkable results are a testament to the efficiency, versatility and broad applicability of the developed synthetic approach, serving as a valuable tool for the synthesis of sulfur pharmacophores. Mechanistic experiments and density functional theory calculations revealed that the initiation and stereocontrol of this reaction are induced by an acyl transfer catalyst. Our research provides an efficient approach for the construction of optically pure sulfur(IV) centres.

5.
Parasitol Res ; 123(4): 197, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38668762

RESUMEN

The majority of ixodid ticks display host-specificity to varying extents. Feeding on different hosts affects their development and reproduction. Consequences can be analyzed at the level of the egg, as it is the initial stage of tick development. Tick egg proteins are abundant and diverse, providing nutrients for embryonic development. However, studies on tick egg profiles are scarce. In this study, we aimed to analyze whether feeding Haemaphysalis qinghaiensis ticks on the yaks (Bos grunniens) and domestic sheep (Ovis aries) has an impact on the variety and variability of the egg proteome. Detached engorged females were used to lay eggs, which were then collected, dewaxed, and subjected to protein extraction. The extracted egg proteins were enzymatically digested using Filter-Aided Sample Preparation (FASP), and the unique peptides were separated and detected by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS). The MS data were searched against the previously constructed whole tick transcriptome library of H. qinghaiensis, and the UniProt database for the identification of tick-derived egg proteins. The analysis revealed 49 and 53 high-confidence proteins identified in eggs collected from B. grunniens (EggBg) and O. aries (EggOa), respectively. Of these, 46 high-confidence proteins were common to both egg types, while three were unique to EggBg and seven to EggOa. All the identified proteins mainly belonged to enzymes, enzyme inhibitors, transporters, and proteins with unknown functions. The differential abundance analysis showed that nine proteins were significantly more present in EggBg, while six were significantly more present in EggOa. Overall, enzymes were the most diverse group, while vitellogenin (Vg) was the most abundant. Blood meal uptake on different hosts has a certain effect on the egg proteome composition and the abundance of some proteins, but it may also lead to compensation of protein roles.


Asunto(s)
Proteínas del Huevo , Ixodidae , Animales , Ixodidae/fisiología , Ixodidae/metabolismo , Ixodidae/crecimiento & desarrollo , Femenino , Proteínas del Huevo/metabolismo , Bovinos , Ovinos , Proteoma , Óvulo/química , Espectrometría de Masas en Tándem , Cromatografía Liquida , Infestaciones por Garrapatas/veterinaria , Infestaciones por Garrapatas/parasitología , Conducta Alimentaria
6.
Front Immunol ; 15: 1295305, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38481990

RESUMEN

Introduction: Ubiquitination is a crucial biological mechanism in humans, essential for regulating vital biological processes, and has been recognized as a promising focus for cancer therapy. Our objective in this research was to discover potential enzymes associated with ubiquitination that may serve as therapeutic targets for individuals with esophageal carcinoma (ESCA). Methods: To identify genes linked to the prognosis of ESCA, we examined mRNA sequencing data from patients with ESCA in the TCGA database. Further investigation into the role of the candidate gene in ESCA was conducted through bioinformatic analyses. Subsequently, we carried out biological assays to assess its impact on ESCA development. Results: Through univariate Cox regression analysis, we identified Ubiquitin Conjugating Enzyme E2 B (UBE2B) as a potential gene associated with the prognosis of ESCA. UBE2B exhibited significant upregulation and was found to be correlated with survival outcomes in ESCA as well as other cancer types. Additionally, UBE2B was observed to be involved in various biological pathways linked to the development of ESCA, including TNF-a signaling via NF-κB, epithelial-mesenchymal transition, inflammatory response, and hypoxia. Moreover, immune-related pathways like B cell activation (GO: 0042113), B cell receptor signaling pathway (GO: 0050853) and B cell mediated immunity (GO:0019724) were also involved. It was found that high expression of UBE2B was correlated with the increase of several kinds of T cells (CD8 T cells, Th1 cells) and macrophages, while effector memory T cell (Tem) and Th17 cells decreased. Furthermore, UBE2B showed potential as a prognostic biomarker for ESCA, displaying high sensitivity and specificity. Notably, proliferation and migration in ESCA cells were effectively suppressed when the expression of UBE2B was knocked down. Conclusions: To summarize, this study has made a discovery regarding the importance of gaining new insights into the role of UBE2B in ESCA. UBE2B might be an oncogene with good ability in predicting and diagnosing ESCA. Consequently, this discovery highlights the feasibility of targeting UBE2B as a viable approach for treating patients with ESCA.


Asunto(s)
Carcinoma , Neoplasias Esofágicas , Humanos , Pronóstico , Oncogenes , Linfocitos B , Neoplasias Esofágicas/genética , Biomarcadores , Enzimas Ubiquitina-Conjugadoras/genética
7.
Fitoterapia ; 175: 105882, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452906

RESUMEN

Falonolide A (1) and B (2), two novel polyyne hybrid phthalides resulting from unprecedented carbon skeleton polymerized by Z-ligustilide and falcarindiol, along with six new related phthalides (3-8), were isolated from Ligusticum chuanxiong Hort. Their structures were elucidated by spectroscopic analysis, computer-assisted structure elucidation (CASE) analysis, DP4+ probability analysis and electronic circular dichroism (ECD) calculations. A plausible biosynthetic pathway for 1-8 was proposed, and the production mechanism of 2 was revealed by density functional theory (DFT) method. Compounds 4 and 6 exhibited significant vasodilatory activity with EC50 of 8.00 ± 0.86 and 6.92 ± 1.02 µM, respectively. Compound 4 also displayed significant inhibitory effect of NO production with EC50 value of 8.82 ± 0.30 µM. Based on the established compounds library, structure-activity relationship analysis of phthalides was explored to provide insights into the drug development of vasodilators and anti-flammatory.

8.
Mol Ecol Resour ; 24(4): e13939, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38372463

RESUMEN

Utilization of faeces has long been a popular approach for genetic and ecological studies of wildlife. However, the success of molecular marker genotyping and genome resequencing is often unpredictable due to insufficient enrichment of endogenous DNA in the total faecal DNA that is dominated by bacterial DNA. Here, we report a simple and cheap method named PEERS to predominantly lyse animal cells over bacteria by using sodium dodecyl sulphate so as to discharge endogenous DNA into liquid phase before bacterial DNA. By brief centrifugation, total DNA with enriched endogenous fraction can be extracted from the supernatant using routine methods. Our assessments showed that the endogenous DNA extracted by PEERS was significantly enriched for various types of faeces from different species, preservation time and conditions. It significantly improves the genotyping correctness and efficiency of genome resequencing with the total additional cost of $ 0.1 and a short incubation step to treat a faecal sample. We also provide methods to assess the enrichment efficiency of mitochondrial and nuclear DNA and models to predict the usability of faecal DNA for genotyping of short tandem repeat, single-nucleotide polymorphism and whole-genome resequencing.


Asunto(s)
ADN , Mamíferos , Animales , ADN Bacteriano/genética , ADN/genética , Heces , Mamíferos/genética , Animales Salvajes/genética
9.
Mar Genomics ; 73: 101087, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38365347

RESUMEN

Tobacco bacterial wilt (TBW) caused by Ralstonia solanacearum is a serious soil-borne disease, which seriously damages the growth of tobacco crops. Bacillus velezensis A5 was isolated from 3000 m deep-sea sediments of the Pacific Ocean, and was found to be antagonistic to TBW. Here, we report the complete genome sequence of strain A5, which has a 4,000,699-bp single circular chromosome with 3827 genes and a G + C content of 46.44%, 87 tRNAs, and 27 rRNAs. A total of 12 gene clusters were identified in the genome of strain A5, which were responsible for the biosynthesis of antibacterial compounds, including surfactin, bacillaene, fengycin, difficidin, bacillibactin, and bacilysin. Additionally, strain A5 was found to contain a series of genes related to the biosynthesis of carbohydrate-active enzymes and secreted proteins. Our results indicate that strain A5 can be considered a promising biocontrol agent against TBW in agricultural fields.


Asunto(s)
Bacillus , Genoma Bacteriano , Océano Pacífico , Bacillus/genética , Bacillus/metabolismo , Bacterias/genética , Análisis de Secuencia
10.
Neural Netw ; 172: 106148, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38309138

RESUMEN

Decoding emotional neural representations from the electroencephalographic (EEG)-based functional connectivity network (FCN) is of great scientific importance for uncovering emotional cognition mechanisms and developing harmonious human-computer interactions. However, existing methods mainly rely on phase-based FCN measures (e.g., phase locking value [PLV]) to capture dynamic interactions between brain oscillations in emotional states, which fail to reflect the energy fluctuation of cortical oscillations over time. In this study, we initially examined the efficacy of amplitude-based functional networks (e.g., amplitude envelope correlation [AEC]) in representing emotional states. Subsequently, we proposed an efficient phase-amplitude fusion framework (PAF) to fuse PLV and AEC and used common spatial pattern (CSP) to extract fused spatial topological features from PAF for multi-class emotion recognition. We conducted extensive experiments on the DEAP and MAHNOB-HCI datasets. The results showed that: (1) AEC-derived discriminative spatial network topological features possess the ability to characterize emotional states, and the differential network patterns of AEC reflect dynamic interactions in brain regions associated with emotional cognition. (2) The proposed fusion features outperformed other state-of-the-art methods in terms of classification accuracy for both datasets. Moreover, the spatial filter learned from PAF is separable and interpretable, enabling a description of affective activation patterns from both phase and amplitude perspectives.


Asunto(s)
Encéfalo , Emociones , Humanos , Emociones/fisiología , Encéfalo/fisiología , Electroencefalografía/métodos , Cognición , Reconocimiento en Psicología
11.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38212289

RESUMEN

Effective visual search is essential for daily life, and attention orientation as well as inhibition of return play a significant role in visual search. Researches have established the involvement of dorsolateral prefrontal cortex in cognitive control during selective attention. However, neural evidence regarding dorsolateral prefrontal cortex modulates inhibition of return in visual search is still insufficient. In this study, we employed event-related functional magnetic resonance imaging and dynamic causal modeling to develop modulation models for two types of visual search tasks. In the region of interest analyses, we found that the right dorsolateral prefrontal cortex and temporoparietal junction were selectively activated in the main effect of search type. Dynamic causal modeling results indicated that temporoparietal junction received sensory inputs and only dorsolateral prefrontal cortex →temporoparietal junction connection was modulated in serial search. Such neural modulation presents a significant positive correlation with behavioral reaction time. Furthermore, theta burst stimulation via transcranial magnetic stimulation was utilized to modulate the dorsolateral prefrontal cortex region, resulting in the disappearance of the inhibition of return effect during serial search after receiving continuous theta burst stimulation. Our findings provide a new line of causal evidence that the top-down modulation by dorsolateral prefrontal cortex influences the inhibition of return effect during serial search possibly through the retention of inhibitory tagging via working memory storage.


Asunto(s)
Corteza Prefontal Dorsolateral , Corteza Prefrontal , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Imagen por Resonancia Magnética , Estimulación Magnética Transcraneal/métodos , Tiempo de Reacción/fisiología
12.
Ticks Tick Borne Dis ; 15(2): 102289, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38070274

RESUMEN

Ticks are blood-sucking ectoparasites that secrete immunomodulatory substances in saliva to hosts during engorging. Cystatins, a tick salivary protein and natural inhibitor of Cathepsins, are attracting growing interest globally because of the immunosuppressive activities and the feasibility as an antigen for developing anti-tick vaccines. This review outlines the classification and the structure of tick Cystatins, and focuses on the anti-inflammatory effects and molecular mechanisms. Tick Cystatins can be divided into four families based on structures and cystatin 1 and cystatin 2 are the most abundant. They are injected into hosts during blood feeding and effectively mitigate the host inflammatory response. Mechanically, tick Cystatins exert anti-inflammatory properties through the inhibition of TLR-NF-κb, JAK-STAT and p38 MAPK signaling pathways. Further investigations are crucial to confirm the reduction of inflammation in other cell types like neutrophils and mast cells, and fully elucidate the underlying mechanism (like the structural mechanism) to make Cystatin a potential candidate for the development of novel anti-inflammation agents.


Asunto(s)
Cistatinas , Garrapatas , Humanos , Animales , Garrapatas/fisiología , Saliva , Antiinflamatorios/farmacología
13.
Mol Neurobiol ; 61(2): 1157-1174, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37697220

RESUMEN

Survivors experiencing acute carbon monoxide poisoning (ACMP) tend to develop white matter injury (WMI). The mechanism of ACMP-induced WMI remains unclear. Considering the role of ferroptosis in initiating oligodendrocyte damage to deteriorate WMI, exploring therapeutic options to attenuate ferroptosis is a feasible approach to alleviating WMI. Our results indicated that ACMP induced accumulation of iron and reactive oxygen species (ROS) eventually leading to WMI and motor impairment after ACMP. Furthermore, ferrostatin-1 reduced iron and ROS deposition to alleviate ferroptosis, thereafter reducing WMI to promote the recovery of motor function. The nuclear factor erythroid-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway was found to be involved in alleviating ferroptosis as seen with the administration of ferrostatin-1. The present study rationalizes that targeting ferroptosis to alleviate WMI is a feasible therapeutic strategy for managing ACMP.


Asunto(s)
Aminopiridinas , Intoxicación por Monóxido de Carbono , Ciclohexilaminas , Ferroptosis , Fenilendiaminas , Sustancia Blanca , Humanos , Especies Reactivas de Oxígeno/metabolismo , Intoxicación por Monóxido de Carbono/complicaciones , Sustancia Blanca/metabolismo , Hierro/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo
14.
Artículo en Inglés | MEDLINE | ID: mdl-38147424

RESUMEN

Electroencephalography (EEG) and surface electromyography (sEMG) have been widely used in the rehabilitation training of motor function. However, EEG signals have poor user adaptability and low classification accuracy in practical applications, and sEMG signals are susceptible to abnormalities such as muscle fatigue and weakness, resulting in reduced stability. To improve the accuracy and stability of interactive training recognition systems, we propose a novel approach called the Attention Mechanism-based Multi-Scale Parallel Convolutional Network (AM-PCNet) for recognizing and decoding fused EEG and sEMG signals. Firstly, we design an experimental scheme for the synchronous collection of EEG and sEMG signals and propose an ERP-WTC analysis method for channel screening of EEG signals. Then, the AM-PCNet network is designed to extract the time-domain, frequency-domain, and mixed-domain information of the EEG and sEMG fusion spectrogram images, and the attention mechanism is introduced to extract more fine-grained multi-scale feature information of the EEG and sEMG signals. Experiments on datasets obtained in the laboratory have shown that the average accuracy of EEG and sEMG fusion decoding is 96.62%. The accuracy is significantly improved compared with the classification performance of single-mode signals. When the muscle fatigue level reaches 50% and 90%, the accuracy is 92.84% and 85.29%, respectively. This study indicates that using this model to fuse EEG and sEMG signals can improve the accuracy and stability of hand rehabilitation training for patients.


Asunto(s)
Electroencefalografía , Mano , Humanos , Electromiografía/métodos , Electroencefalografía/métodos , Mano/fisiología , Fatiga Muscular , Extremidad Superior
15.
Mar Genomics ; 72: 101071, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38008533

RESUMEN

Bacillus species have been considered as promising biological control agents due to their excellent antimicrobial ability. Bacillus cereus strain Z4 was isolated from 2000 m deep sea sediments of the Western Pacific Ocean, which possesses significant antifungal activity against Phytophthora nicotianae, the pathogenic fungus of tobacco black shank disease. To reveal the underlying antifungal genetic mechanisms, here, we report the complete genomic sequence of the strain Z4. The genome has one circular chromosome of 5,664,309 bp with a G + C content of 35.31%, 109 tRNAs, and 43 rRNAs. Genomic analysis identified 10 gene clusters related to the biosynthesis of biocontrol active compounds, including bacillibactin, petrobactin, fengycin, and molybdenum cofactor. Meanwhile, 6 gene clusters were responsible for the biosynthesis of metabolites with unknown functions. Strain Z4 also contains a large number of genes encoding carbohydrate-active enzymes and secreted proteins, respectively. The whole genomic analysis of Bacillus cereus Z4 may provide a valuable reference for elucidating its biocontrol mechanism against tobacco black shank.


Asunto(s)
Bacillus cereus , Bacillus , Bacillus cereus/genética , Bacillus cereus/metabolismo , Antifúngicos/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/microbiología , Océano Pacífico , Bacillus/genética
16.
Brain Res Bull ; 203: 110758, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37704055

RESUMEN

This study aims to explore a method based on brain networks for implicit attention by using wavelet coherence as feature to identify individual targets in the visual field, find the optimal classification rhythm and time window, and investigate the relationship between the optimal rhythm and N2pc event-related potential. The study uses a weighted minimum norm estimate to locate the sources of the scalp EEG and reconstructs the source time series. The functional connectivity between brain areas during the visual search process is evaluated using wavelet coherence analysis, and a lateral difference network is constructed based on the difference in coherence values between the left and right visual fields. A support vector machine classifier is trained based on the wavelet coherence network features to identify the target in the left or right visual field. We also extract N2pc from the source activity data of the parieto-occipital brain region and record the time period in which N2pc occurred. The study finds that the best classification performance is achieved in the theta rhythm from 200 to 400 ms and achieved an average classification accuracy of 87% (chance level: 51.07%) in a serial search task. And this time window corresponds to the time period when N2pc appeared. The results show that the use of wavelet coherence analysis to evaluate the functional connectivity between brain areas during the visual search process provides a new approach for analyzing brain activity. The study's findings regarding the relationship between the N2pc and theta rhythm and the effectiveness of using wavelet coherence network features based on the theta rhythm for visual search classification contribute to the understanding of the neural mechanisms underlying visual search.


Asunto(s)
Electroencefalografía , Potenciales Evocados , Electroencefalografía/métodos , Encéfalo , Atención , Ritmo Teta
17.
J Neurosci Methods ; 398: 109959, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37661055

RESUMEN

BACKGROUND: Music can evoke intense emotions and music emotion is a complex cognitive process. However, we know little about the cognitive mechanisms underlying these processes, and there are significant individual differences in the emotional responses to the same musical stimuli. NEW METHOD: We used the inter-subject representational similarity analysis (IS-RSA) method to investigate the shared music emotion responses across multiple participants. In addition, we extended IS-RSA to estimate the group cross-frequency coupling effects of music emotion. Based on the cross-frequency coupling IS-RSA, we analyzed the differences in cross-frequency coupling patterns under different music emotions using MI. Comparison of existing methods: most current IS-RSA analyses focus on within-frequency band analysis. However, the cognitive processing of music emotion involves not only activation and brain network connections differences within frequency bands but also information communication between frequency bands. RESULTS: The results of the within-frequency band IS-RSA analysis showed that the theta and gamma frequency bands play important roles in the inter-participant consistency of music emotion. The inter-frequency band IS-RSA analysis showed that the theta-beta coupling pattern exhibited stronger inter-participant consistency compared to the theta-gamma coupling pattern, and the theta-beta coupling had significant consistent representation across various music conditions. Through the significant regions of cross-frequency coupling representation similarity analysis, we performed phase-amplitude coupling analysis on FC4-C6 and FC4-Pz connections. For the theta-beta coupling pattern, we found that the MI of these two connections exhibited different coupling patterns under different music conditions, and they showed a significant decrease compared to the baseline period.


Asunto(s)
Música , Humanos , Música/psicología , Electroencefalografía/métodos , Emociones/fisiología , Encéfalo/fisiología , Percepción Auditiva/fisiología
18.
J Org Chem ; 88(19): 13771-13781, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37695889

RESUMEN

The desymmetrization of meso-vic-diols with a reversal of enantioselectivity catalyzed by chiral pyridine-N-oxides with l-proline as a single source of chirality is reported. With chiral 3-substituted ArPNO C2c and 2-substituted 4-(dimethylamino)pyridine-N-oxide C3b as catalysts, a wide range of monoesters were obtained with satisfactory results with a complete and controlled switch in stereoselectivity (up to 97:3 and 1:99 er). Chiral six-membered carbocyclic uracil nucleosides were generated with excellent enantioselectivities after derivatization. A series of control experiments and density functional theory (DFT) calculations supported that the reaction proceeded in a bifunctional activated manner, where the N-oxide groups and N-H proton of the amides were vital for catalytic reactivity and stereocontrol. The DFT calculation also supported the distance-directed switching of enantioselectivity, in which the l-prolinamide moiety moved from the C3 to C2 position on the pyridine ring, resulting in the H-bond interaction between the amide N-H and OH group of meso-vic-diol also shifted from one hydroxyl group to another.

19.
Front Neurosci ; 17: 1235480, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37600005

RESUMEN

Attention and audiovisual integration are crucial subjects in the field of brain information processing. A large number of previous studies have sought to determine the relationship between them through specific experiments, but failed to reach a unified conclusion. The reported studies explored the relationship through the frameworks of early, late, and parallel integration, though network analysis has been employed sparingly. In this study, we employed time-varying network analysis, which offers a comprehensive and dynamic insight into cognitive processing, to explore the relationship between attention and auditory-visual integration. The combination of high spatial resolution functional magnetic resonance imaging (fMRI) and high temporal resolution electroencephalography (EEG) was used. Firstly, a generalized linear model (GLM) was employed to find the task-related fMRI activations, which was selected as regions of interesting (ROIs) for nodes of time-varying network. Then the electrical activity of the auditory-visual cortex was estimated via the normalized minimum norm estimation (MNE) source localization method. Finally, the time-varying network was constructed using the adaptive directed transfer function (ADTF) technology. Notably, Task-related fMRI activations were mainly observed in the bilateral temporoparietal junction (TPJ), superior temporal gyrus (STG), primary visual and auditory areas. And the time-varying network analysis revealed that V1/A1↔STG occurred before TPJ↔STG. Therefore, the results supported the theory that auditory-visual integration occurred before attention, aligning with the early integration framework.

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