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1.
Phys Chem Chem Phys ; 26(13): 10399-10407, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38502152

RESUMO

Pressure alters the nature of chemical bonds and triggers novel reactions. Here, we employed first-principles calculations combined with the CALYPSO structural search technique to reveal the charge transfer reversal between Ca and Te under high pressure in the calcium-tellurium compound (CaxTe1-x, x = 1/4, 1/3, 1/2, 2/3). We predict several new phases with conventional and unconventional compounds and found an unfamiliar phenomenon: the Ca-Te compounds will reverse charge transfer between Ca and Te atoms and decompose into elemental solids under pressure. The Bader charge analyses indicate that the Ca2+ ion gains electrons and becomes an anion under high pressure. This leads to a weakened electrostatic interaction between Ca and Te and ultimately results in decomposition. The calculated band occupation number suggests that the occupation of Ca 3d orbitals under high pressure corresponds to this atypical phenomenon. Our results demonstrated the reverse charge transfer between Ca and Te and, in addition, clarified the mechanism of CaxTe1-x decomposition into solid Ca and Te elements under high pressure, providing important insights into the evolution of the properties of alkaline-earth chalcogenide compounds under high pressure.

2.
Neuroimage ; 284: 120455, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37952779

RESUMO

Real-time fMRI (rt-fMRI) neurofeedback (NF) training is a novel non-invasive technique for volitional brain modulation. Given the important role of the anterior insula (AI) in human cognitive and affective processes, it has become one of the most investigated regions in rt-fMRI studies. Most rt-fMRI insula studies employed emotional recall/imagery as the regulation strategy, which may be less effective for psychiatric disorders characterized by altered emotional processing. The present study thus aimed to examine the feasibility of a novel interoceptive strategy based on heartbeat detection in rt-fMRI guided AI regulation and its associated behavioral changes using a randomized double-blind, sham feedback-controlled between-subject design. 66 participants were recruited and randomly assigned to receive either NF from the left AI (LAI) or sham feedback from a control region while using the interoceptive strategy. N = 57 participants were included in the final data analyses. Empathic and interoceptive pre-post training changes were collected as behavioral measures of NF training effects. Results showed that participants in the NF group exhibited stronger LAI activity than the control group with LAI activity being positively correlated with interoceptive accuracy following NF training, although there were no significant increases of LAI activity over training sessions. Importantly, ability of LAI regulation could be maintained in a transfer session without feedback. Successful LAI regulation was associated with strengthened functional connectivity of the LAI with cognitive control, memory and learning, and salience/interoceptive networks. The present study demonstrated for the first time the efficacy of a novel regulation strategy based on interoceptive processing in up-regulating LAI activity. Our findings also provide proof of concept for the translational potential of this strategy in rt-fMRI AI regulation of psychiatric disorders characterized by altered emotional processing.


Assuntos
Imageamento por Ressonância Magnética , Neurorretroalimentação , Humanos , Imageamento por Ressonância Magnética/métodos , Neurorretroalimentação/métodos , Emoções/fisiologia , Encéfalo/fisiologia , Empatia , Mapeamento Encefálico/métodos
3.
Biochem Biophys Res Commun ; 533(1): 104-109, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-32933749

RESUMO

NRT1.2 has been characterized as a low-affinity nitrate transporter and an abscisic acid (ABA) transporter in Arabidopsis. In this study, we demonstrate that NRT1.2 positively regulated the ABA response during germination and seedling development. The transgenic Arabidopsis NRT1.2-over-expressionors showed increased sensitivity to ABA during these processes. qRT-PCR assays indicated that NRT1.2 over-production in 7-days-old seedlings up-regulated the expression of ABA-responsive genes: ABI1, ABI2, ABI3, ABI4, ABI5, RAB18, RD29A, and RD29B and PHOSPHOLIPASE Dα1 (PLDα1). The expression of these genes was suppressed in the nrt1.2 mutant in comparison with the wild type following ABA treatment. Importantly, bimolecular fluorescence complementation assays indicated that NRT1.2 interacts with PLDα1 at the plasma membrane. Their interaction was further confirmed by using yeast two hybrid (Y2H) experiments with the mating-based split ubiquitin system (MbSUS). Moreover, genetic assays indicated that PLDα1 acts epistatically on NRT1.2 to affect ABA signaling. Taken together, our results provide detailed mechanisms of NRT1.2 in ABA-mediated seed germination and seedling development.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Fosfolipase D/metabolismo , Proteínas de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Proteínas de Transporte de Ânions/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Germinação , Fosfolipase D/genética , Proteínas de Plantas/genética , Mapas de Interação de Proteínas , Plântula/genética , Plântula/metabolismo
4.
Int J Neural Syst ; 30(11): 2050014, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32308081

RESUMO

Thalamus interacts with cortical areas, generating oscillations characterized by their rhythm and levels of synchrony. However, little is known of what function the rhythmic dynamic may serve in thalamocortical couplings. This work introduced a general approach to investigate the modulatory contribution of rhythmic scalp network to the thalamo-frontal couplings in juvenile myoclonic epilepsy (JME) and frontal lobe epilepsy (FLE). Here, time-varying rhythmic network was constructed using the adapted directed transfer function between EEG electrodes, and then was applied as a modulator in fMRI-based thalamocortical functional couplings. Furthermore, the relationship between corticocortical connectivity and rhythm-dependent thalamocortical coupling was examined. The results revealed thalamocortical couplings modulated by EEG scalp network have frequency-dependent characteristics. Increased thalamus- sensorimotor network (SMN) and thalamus-default mode network (DMN) couplings in JME were strongly modulated by alpha band. These thalamus-SMN couplings demonstrated enhanced association with SMN-related corticocortical connectivity. In addition, altered theta-dependent and beta-dependent thalamus-frontoparietal network (FPN) couplings were found in FLE. The reduced theta-dependent thalamus-FPN couplings were associated with the decreased FPN-related corticocortical connectivity. This study proposed interactive links between the rhythmic modulation and thalamocortical coupling. The crucial role of SMN and FPN in subcortical-cortical circuit may have implications for intervention in generalized and focal epilepsy.


Assuntos
Epilepsia do Lobo Frontal , Epilepsia Mioclônica Juvenil , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Tálamo
5.
AMIA Annu Symp Proc ; 2020: 243-252, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33936396

RESUMO

Dietary supplements (DSs) have been widely used in the U.S. and evaluated in clinical trials as potential interventions for various diseases. However, many clinical trials face challenges in recruiting enough eligible patients in a timely fashion, causing delays or even early termination. Using electronic health records to find eligible patients who meet clinical trial eligibility criteria has been shown as a promising way to assess recruitment feasibility and accelerate the recruitment process. In this study, we analyzed the eligibility criteria of 100 randomly selected DS clinical trials and identified both computable and non-computable criteria. We mapped annotated entities to OMOP Common Data Model (CDM) with novel entities (e.g., DS). We also evaluated a deep learning model (Bi-LSTM-CRF) for extracting these entities on CLAMP platform, with an average F1 measure of 0.601. This study shows the feasibility of automatic parsing of the eligibility criteria following OMOP CDM for future cohort identification.


Assuntos
Ensaios Clínicos como Assunto , Aprendizado Profundo , Suplementos Nutricionais , Registros Eletrônicos de Saúde , Seleção de Pacientes , Bases de Dados Factuais , Estudos de Viabilidade , Humanos , Modelos Teóricos , Processamento de Linguagem Natural , Prática Associada
6.
Psychother Psychosom ; 88(1): 5-15, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30699438

RESUMO

BACKGROUND: Deficient emotion regulation and exaggerated anxiety represent a major transdiagnostic psychopathological marker. On the neural level these deficits have been closely linked to impaired, yet treatment-sensitive, prefrontal regulatory control over the amygdala. Gaining direct control over these pathways could therefore provide an innovative and promising intervention to regulate exaggerated anxiety. To this end the current proof-of-concept study evaluated the feasibility, functional relevance and maintenance of a novel connectivity-informed real-time fMRI neurofeedback training. METHODS: In a randomized crossover sham-controlled design, 26 healthy subjects with high anxiety underwent real-time fMRI-guided neurofeedback training to enhance connectivity between the ventrolateral prefrontal cortex (vlPFC) and the amygdala (target pathway) during threat exposure. Maintenance of regulatory control was assessed after 3 days and in the absence of feedback. Training-induced changes in functional connectivity of the target pathway and anxiety ratings served as primary outcomes. RESULTS: Training of the target, yet not the sham control, pathway significantly increased amygdala-vlPFC connectivity and decreased levels of anxiety. Stronger connectivity increases were significantly associated with higher anxiety reduction on the group level. At the follow-up, volitional control over the target pathway was maintained in the absence of feedback. CONCLUSIONS: The present results demonstrate for the first time that successful self-regulation of amygdala-prefrontal top-down regulatory circuits may represent a novel intervention to control anxiety. As such, the present findings underscore both the critical contribution of amygdala-prefrontal circuits to emotion regulation and the therapeutic potential of connectivity-informed real-time neurofeedback.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Ansiedade/terapia , Neuroimagem Funcional/métodos , Rede Nervosa/fisiopatologia , Neurorretroalimentação/métodos , Avaliação de Resultados em Cuidados de Saúde , Córtex Pré-Frontal/fisiopatologia , Autocontrole , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Ansiedade/diagnóstico por imagem , Ansiedade/fisiopatologia , Estudos Cross-Over , Humanos , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Estudo de Prova de Conceito
7.
Neural Plast ; 2018: 2821832, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29853841

RESUMO

Schizophrenia is often associated with behavior abnormality in the cognitive and affective domain. Music intervention is used as a complementary treatment for improving symptoms in patients with schizophrenia. However, the neurophysiological correlates of these remissions remain poorly understood. Here, we investigated the effects of music intervention in neural circuits through functional magnetic resonance imaging (fMRI) study in schizophrenic subjects. Under the standard care, patients were randomly assigned to music and non-music interventions (MTSZ, UMTSZ) for 1 month. Resting-state fMRI were acquired over three time points (baseline, 1 month, and 6 months later) in patients and analyzed using functional connectivity strength (FCS) and seed-based functional connection (FC) approaches. At baseline, compared with healthy controls, decreased FCS in the right middle temporal gyrus (MTG) was observed in patients. However, after music intervention, the functional circuitry of the right MTG, which was related with the function of emotion and sensorimotor, was improved in MTSZ. Furthermore, the FC increments were significantly correlated with the improvement of symptoms, while vanishing 6 months later. Together, these findings provided evidence that music intervention might positively modulate the functional connectivity of MTG in patients with schizophrenia; such changes might be associated with the observed therapeutic effects of music intervention on neurocognitive function. This trial is registered with ChiCTR-OPC-14005339.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Musicoterapia/métodos , Rede Nervosa/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/terapia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Feminino , Seguimentos , Humanos , Masculino , Rede Nervosa/fisiopatologia , Esquizofrenia/fisiopatologia , Resultado do Tratamento
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