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1.
J Immunol ; 210(12): 1962-1973, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37144844

RESUMEN

Diabetes-aggravated myocardial ischemia-reperfusion (MI/R) injury remains an urgent medical issue, and the molecular mechanisms involved with diabetes and MI/R injury remain largely unknown. Previous studies have shown that inflammation and P2X7 signaling participate in the pathogenesis of the heart under individual conditions. It remains to be explored if P2X7 signaling is exacerbated or alleviated under double insults. We established a high-fat diet and streptozotocin-induced diabetic mouse model, and we compared the differences in immune cell infiltration and P2X7 expression between diabetic and nondiabetic mice after 24 h of reperfusion. The antagonist and agonist of P2X7 were administered before and after MI/R. Our study showed that the MI/R injury of diabetic mice was characterized by increased infarct area, impaired ventricular contractility, more apoptosis, aggravated immune cell infiltration, and overactive P2X7 signaling compared with nondiabetic mice. The major trigger of increased P2X7 was the MI/R-induced recruitment of monocytes and macrophages, and diabetes can be a synergistic factor in this process. Administration of P2X7 agonist eliminated the differences in MI/R injury between nondiabetic mice and diabetic mice. Both 2 wk of brilliant blue G injection before MI/R and acutely administered A438079 at the time of MI/R injury attenuated the role of diabetes in exacerbating MI/R injury, as evidenced by decreased infarct size, improved cardiac function, and inhibition of apoptosis. Additionally, brilliant blue G blockade decreased the heart rate after MI/R, which was accompanied by downregulation of tyrosine hydroxylase expression and nerve growth factor transcription. In conclusion, targeting P2X7 may be a promising strategy for reducing the risk of MI/R injury in diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Infarto del Miocardio , Daño por Reperfusión Miocárdica , Ratones , Animales , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/patología , Diabetes Mellitus Experimental/metabolismo , Regulación hacia Arriba , Apoptosis , Infarto del Miocardio/patología , Infarto/metabolismo , Inflamación/metabolismo , Miocitos Cardíacos/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(42): e2205460119, 2022 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-36215473

RESUMEN

Relapsing fever due to Borrelia hermsii is characterized by recurrent bacteremia episodes. However, infection of B. hermsii, if not treated early, can spread to various organs including the central nervous system (CNS). CNS disease manifestations are commonly referred to as relapsing fever neuroborreliosis (RFNB). In the mouse model of B. hermsii infection, we have previously shown that the development of RFNB requires innate immune cells as well as T cells. Here, we found that prior to the onset of RFNB, an increase in the systemic proinflammatory cytokine response followed by sustained levels of IP-10 concurrent with the CNS disease phase. RNA sequencing analysis of the spinal cord tissue during the disease phase revealed an association of the interleukin (IL)-17 signaling pathway in RFNB. To test a possible role for IL-17 in RFNB, we compared B. hermsii infection in wild-type and IL-17A-/- mice. Although the onset of bacteremia and protective anti-B. hermsii antibody responses occurred similarly, the blood-brain barrier permeability, proinflammatory cytokine levels, immune cell infiltration in the spinal cord, and RFNB manifestations were significantly diminished in IL-17A-/- mice compared to wild-type mice. Treatment of B. hermsii-infected wild-type mice with anti-IL-17A antibody ameliorated the severity of spinal cord inflammation, microglial cell activation, and RFNB. These data suggest that the IL-17 signaling pathway plays a major role in the pathogenesis of RFNB, and IL-17A blockade may be a therapeutic modality for controlling neuroborreliosis.


Asunto(s)
Bacteriemia , Fiebre Recurrente , Animales , Quimiocina CXCL10 , Citocinas , Interleucina-17 , Interleucinas , Ratones , Fiebre Recurrente/genética
3.
J Neurosci ; 43(40): 6760-6778, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37607820

RESUMEN

Unconscious acquisition of sequence structure from experienced events can lead to explicit awareness of the pattern through extended practice. Although the implicit-to-explicit transition has been extensively studied in humans using the serial reaction time (SRT) task, the subtle neural activity supporting this transition remains unclear. Here, we investigated whether frequency-specific neural signal transfer contributes to this transition. A total of 208 participants (107 females) learned a sequence pattern through a multisession SRT task, allowing us to observe the transitions. Session-by-session measures of participants' awareness for sequence knowledge were conducted during the SRT task to identify the session when the transition occurred. By analyzing time course RT data using switchpoint modeling, we identified an increase in learning benefit specifically at the transition session. Electroencephalogram (EEG)/magnetoencephalogram (MEG) recordings revealed increased theta power in parietal (precuneus) regions one session before the transition (pretransition) and a prefrontal (superior frontal gyrus; SFG) one at the transition session. Phase transfer entropy (PTE) analysis confirmed that directional theta transfer from precuneus → SFG occurred at the pretransition session and its strength positively predicted learning improvement at the subsequent transition session. Furthermore, repetitive transcranial magnetic stimulation (TMS) modulated precuneus theta power and altered transfer strength from precuneus to SFG, resulting in changes in both transition rate and learning benefit at that specific point of transition. Our brain-stimulation evidence supports a role for parietal → prefrontal theta signal transfer in igniting conscious awareness of implicitly acquired knowledge.SIGNIFICANCE STATEMENT There exists a pervasive phenomenon wherein individuals unconsciously acquire sequence patterns from their environment, gradually becoming aware of the underlying regularities through repeated practice. While previous studies have established the robustness of this implicit-to-explicit transition in humans, the refined neural mechanisms facilitating conscious access to implicit knowledge remain poorly understood. Here, we demonstrate that prefrontal activity, known to be crucial for conscious awareness, is triggered by neural signal transfer originating from the posterior brain region, specifically the precuneus. By employing brain stimulation techniques, we establish a causal link between neural signal transfer and the occurrence of awareness. Our findings unveil a mechanism by which implicit knowledge becomes consciously accessible in human cognition.


Asunto(s)
Concienciación , Aprendizaje , Femenino , Humanos , Concienciación/fisiología , Aprendizaje/fisiología , Corteza Prefrontal/fisiología , Tiempo de Reacción/fisiología , Electroencefalografía
4.
Hum Brain Mapp ; 45(10): e26768, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38949537

RESUMEN

Structural neuroimaging data have been used to compute an estimate of the biological age of the brain (brain-age) which has been associated with other biologically and behaviorally meaningful measures of brain development and aging. The ongoing research interest in brain-age has highlighted the need for robust and publicly available brain-age models pre-trained on data from large samples of healthy individuals. To address this need we have previously released a developmental brain-age model. Here we expand this work to develop, empirically validate, and disseminate a pre-trained brain-age model to cover most of the human lifespan. To achieve this, we selected the best-performing model after systematically examining the impact of seven site harmonization strategies, age range, and sample size on brain-age prediction in a discovery sample of brain morphometric measures from 35,683 healthy individuals (age range: 5-90 years; 53.59% female). The pre-trained models were tested for cross-dataset generalizability in an independent sample comprising 2101 healthy individuals (age range: 8-80 years; 55.35% female) and for longitudinal consistency in a further sample comprising 377 healthy individuals (age range: 9-25 years; 49.87% female). This empirical examination yielded the following findings: (1) the accuracy of age prediction from morphometry data was higher when no site harmonization was applied; (2) dividing the discovery sample into two age-bins (5-40 and 40-90 years) provided a better balance between model accuracy and explained age variance than other alternatives; (3) model accuracy for brain-age prediction plateaued at a sample size exceeding 1600 participants. These findings have been incorporated into CentileBrain (https://centilebrain.org/#/brainAGE2), an open-science, web-based platform for individualized neuroimaging metrics.


Asunto(s)
Envejecimiento , Encéfalo , Imagen por Resonancia Magnética , Humanos , Adolescente , Femenino , Anciano , Adulto , Niño , Adulto Joven , Masculino , Encéfalo/diagnóstico por imagen , Encéfalo/anatomía & histología , Encéfalo/crecimiento & desarrollo , Anciano de 80 o más Años , Preescolar , Persona de Mediana Edad , Envejecimiento/fisiología , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Neuroimagen/normas , Tamaño de la Muestra
5.
BMC Med ; 22(1): 223, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831366

RESUMEN

BACKGROUND: The trajectory of attention-deficit hyperactivity disorder (ADHD) symptoms in children and adolescents, encompassing descending, stable, and ascending patterns, delineates their ADHD status as remission, persistence or late onset. However, the neural and genetic underpinnings governing the trajectory of ADHD remain inadequately elucidated. METHODS: In this study, we employed neuroimaging techniques, behavioral assessments, and genetic analyses on a cohort of 487 children aged 6-15 from the Children School Functions and Brain Development project at baseline and two follow-up tests for 1 year each (interval 1: 1.14 ± 0.32 years; interval 2: 1.14 ± 0.30 years). We applied a Latent class mixed model (LCMM) to identify the developmental trajectory of ADHD symptoms in children and adolescents, while investigating the neural correlates through gray matter volume (GMV) analysis and exploring the genetic underpinnings using polygenic risk scores (PRS). RESULTS: This study identified three distinct trajectories (ascending-high, stable-low, and descending-medium) of ADHD symptoms from childhood through adolescence. Utilizing the linear mixed-effects (LME) model, we discovered that attention hub regions served as the neural basis for these three developmental trajectories. These regions encompassed the left anterior cingulate cortex/medial prefrontal cortex (ACC/mPFC), responsible for inhibitory control; the right inferior parietal lobule (IPL), which facilitated conscious focus on exogenous stimuli; and the bilateral middle frontal gyrus/precentral gyrus (MFG/PCG), accountable for regulating both dorsal and ventral attention networks while playing a crucial role in flexible modulation of endogenous and extrinsic attention. Furthermore, our findings revealed that individuals in the ascending-high group exhibited the highest PRS for ADHD, followed by those in the descending-medium group, with individuals in the stable-low group displaying the lowest PRS. Notably, both ascending-high and descending-medium groups had significantly higher PRS compared to the stable-low group. CONCLUSIONS: The developmental trajectory of ADHD symptoms in the general population throughout childhood and adolescence can be reliably classified into ascending-high, stable-low, and descending-medium groups. The bilateral MFG/PCG, left ACC/mPFC, and right IPL may serve as crucial brain regions involved in attention processing, potentially determining these trajectories. Furthermore, the ascending-high pattern of ADHD symptoms exhibited the highest PRS for ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Humanos , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Niño , Adolescente , Masculino , Femenino , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/crecimiento & desarrollo , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Neuroimagen , Estudios de Cohortes
6.
NMR Biomed ; 37(5): e5098, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38224670

RESUMEN

The overlapping peaks of the target chemical exchange saturation transfer (CEST) solutes and other unknown CEST solutes affect the quantification results and accuracy of the chemical exchange parameters-the fractional concentration, f b , exchange rate, k b , and transverse relaxation rate, R 2 b -for the target solutes. However, to date, no method has been established for assessing the overlapping peaks. This study aimed to develop a method for quantifying the f b , k b , and R 2 b values of a specific CEST solute, as well as assessing the overlap between the CEST peaks of the specific solute(s) and other unknown solutes. A simplified R 1 ρ model was proposed, assuming linear approximation of the other solutes' contributions to R 1 ρ . A CEST data acquisition scheme was applied with various saturation offsets and saturation powers. In addition to fitting the f b , k b , and R 2 b values of the specific solute, the overlapping condition was evaluated based on the root mean square error (RMSE) between the trajectories of the acquired and synthesized data. Single-solute and multi-solute phantoms with various phosphocreatine (PCr) concentrations and pH values were used to calculate the f b and k b of PCr and the corresponding RMSE. The feasibility of RMSE for evaluating the overlapping condition, and the accurate fitting of f b and k b in weak overlapping conditions, were verified. Furthermore, the method was employed to quantify the nuclear Overhauser effect signal in rat brains and the PCr signal in rat skeletal muscles, providing results that were consistent with those reported in previous studies. In summary, the proposed approach can be applied to evaluate the overlapping condition of CEST peaks and quantify the f b , k b , and R 2 b values of specific solutes, if the weak overlapping condition is satisfied.


Asunto(s)
Algoritmos , Imagen por Resonancia Magnética , Ratas , Animales , Imagen por Resonancia Magnética/métodos , Fantasmas de Imagen
7.
Cereb Cortex ; 33(10): 6486-6493, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-36587299

RESUMEN

Humans excel at constructing mental representations of speech streams in the absence of external auditory input: the internal experience of speech imagery. Elucidating the neural processes underlying speech imagery is critical to understanding this higher-order brain function in humans. Here, using functional magnetic resonance imaging, we investigated the shared and distinct neural correlates of imagined and perceived speech by asking participants to listen to poems articulated by a male voice (perception condition) and to imagine hearing poems spoken by that same voice (imagery condition). We found that compared to baseline, speech imagery and perception activated overlapping brain regions, including the bilateral superior temporal gyri and supplementary motor areas. The left inferior frontal gyrus was more strongly activated by speech imagery than by speech perception, suggesting functional specialization for generating speech imagery. Although more research with a larger sample size and a direct behavioral indicator is needed to clarify the neural systems underlying the construction of complex speech imagery, this study provides valuable insights into the neural mechanisms of the closely associated but functionally distinct processes of speech imagery and perception.


Asunto(s)
Percepción del Habla , Habla , Humanos , Masculino , Mapeo Encefálico , Imaginación , Percepción Auditiva , Imagen por Resonancia Magnética
8.
Cereb Cortex ; 33(5): 2260-2272, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-35641153

RESUMEN

Attention and reading are essential skills for successful schooling and in adult life. While previous studies have documented that attention development supports reading acquisition, whether and how learning to read may improve attention among school-age children and the brain structural and functional development that may be involved remain unknown. In this prospective longitudinal study, we examined bidirectional and longitudinal predictions between attention and reading development and the neural mediators of attention and reading development among school-age children using cross-lagged panel modeling. The results showed that better baseline reading performance significantly predicted better attention performance one year later after controlling for baseline attention performance. In contrast, after controlling for baseline reading performance, attention did not significantly predict reading performance one year later, while more attention problems also significantly predicted worse reading performance. Both the increasing gray matter volume of the left middle frontal gyrus and the increasing connectivity between the left middle frontal gyrus and the ventral attention network mediated the above significant longitudinal predictions. This study, directly revealed that reading skills may predict the development of important cognitive functions, such as attention, in school-age children. Therefore, learning to read is not only a challenge for school-age children but is also an important way to optimize attention and brain development.


Asunto(s)
Encéfalo , Lectura , Niño , Adulto , Humanos , Estudios Longitudinales , Estudios Prospectivos , Lóbulo Frontal , Imagen por Resonancia Magnética
9.
Cereb Cortex ; 33(11): 7076-7087, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-36843051

RESUMEN

Human functional brain networks are dynamically organized to enable cognitive and behavioral flexibility to meet ever-changing environmental demands. Frontal-parietal network (FPN) and default mode network (DMN) are recognized to play an essential role in executive functions such as working memory. However, little is known about the developmental differences in the brain-state dynamics of these two networks involved in working memory from childhood to adulthood. Here, we implemented Bayesian switching dynamical systems approach to identify brain states of the FPN and DMN during working memory in 69 school-age children and 51 adults. We identified five brain states with rapid transitions, which are characterized by dynamic configurations among FPN and DMN nodes with active and inactive engagement in different task demands. Compared with adults, children exhibited less frequent brain states with the highest activity in FPN nodes dominant to high demand, and its occupancy rate increased with age. Children preferred to attain inactive brain states with low activity in both FPN and DMN nodes. Moreover, children exhibited lower transition probability from low-to-high demand states and such a transition was positively correlated with working memory performance. Notably, higher transition probability from low-to-high demand states was associated with a stronger structural connectivity across FPN and DMN, but with weaker structure-function coupling of these two networks. These findings extend our understanding of how FPN and DMN nodes are dynamically organized into a set of transient brain states to support moment-to-moment information updating during working memory and suggest immature organization of these functional brain networks in childhood, which is constrained by the structural connectivity.


Asunto(s)
Mapeo Encefálico , Memoria a Corto Plazo , Adulto , Niño , Humanos , Adolescente , Adulto Joven , Teorema de Bayes , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Vías Nerviosas/diagnóstico por imagen
10.
Cereb Cortex ; 33(11): 6803-6817, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-36657772

RESUMEN

Individualized cortical network topography (ICNT) varies between people and exhibits great variability in the association networks in the human brain. However, these findings were mainly discovered in Western populations. It remains unclear whether and how ICNT is shaped by the non-Western populations. Here, we leveraged a multisession hierarchical Bayesian model to define individualized functional networks in White American and Han Chinese populations with data from both US and Chinese Human Connectome Projects. We found that both the size and spatial topography of individualized functional networks differed between White American and Han Chinese groups, especially in the heteromodal association cortex (including the ventral attention, control, language, dorsal attention, and default mode networks). Employing a support vector machine, we then demonstrated that ethnicity-related ICNT diversity can be used to identify an individual's ethnicity with high accuracy (74%, pperm < 0.0001), with heteromodal networks contributing most to the classification. This finding was further validated through mass-univariate analyses with generalized additive models. Moreover, we reveal that the spatial heterogeneity of ethnic diversity in ICNT correlated with fundamental properties of cortical organization, including evolutionary cortical expansion, brain myelination, and cerebral blood flow. Altogether, this case study highlights a need for more globally diverse and publicly available neuroimaging datasets.


Asunto(s)
Conectoma , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Teorema de Bayes , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Neuroimagen , Conectoma/métodos , Red Nerviosa/fisiología
11.
Cereb Cortex ; 33(9): 5251-5263, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36320154

RESUMEN

The default mode network (DMN) is a workspace for convergence of internal and external information. The frontal parietal network (FPN) is indispensable to executive functioning. Yet, how they interplay to support cognitive development remains elusive. Using longitudinal developmental fMRI with an n-back paradigm, we show a heterogeneity of maturational changes in multivoxel activity and network connectivity among DMN and FPN nodes in 528 children and 103 young adults. Compared with adults, children exhibited prominent longitudinal improvement but still inferior behavioral performance, which paired with less pronounced DMN deactivation and weaker FPN activation in children, but stronger DMN coupling with FPN regions. Children's DMN reached an adult-like level earlier than FPN at both multivoxel activity pattern and intranetwork connectivity levels. Intrinsic DMN-FPN internetwork coupling in children mediated the relationship between age and working memory-related functional coupling of these networks, with posterior cingulate cortex (PCC)-dorsolateral prefrontal cortex (DLPFC) coupling emerging as most prominent pathway. Coupling of PCC-DLPFC may further work together with task-invoked activity in PCC to account for longitudinal improvement in behavioral performance in children. Our findings suggest that the DMN provides a scaffolding effect in support of an immature FPN that is critical for the development of executive functions in children.


Asunto(s)
Cognición , Red en Modo Predeterminado , Adulto Joven , Niño , Humanos , Función Ejecutiva/fisiología , Memoria a Corto Plazo/fisiología , Lóbulo Frontal , Imagen por Resonancia Magnética , Mapeo Encefálico , Encéfalo/fisiología , Red Nerviosa/fisiología
12.
Neuroimage ; 266: 119823, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36535322

RESUMEN

Sleep regulation and functioning may rely on systematic coordination throughout the whole brain, including the cerebellum. However, whether and how interactions between the cerebellum and other brain regions vary across sleep stages remain poorly understood. Here, using simultaneous EEG-fMRI recordings captured from 73 participants during wakefulness and non-rapid eye movement (NREM) sleep, we constructed cerebellar connectivity among intrinsic functional networks with intra-cerebellar, neocortical and subcortical regions. We uncovered that cerebellar connectivity exhibited sleep-dependent alterations: slight differences between wakefulness and N1/N2 sleep and greater changes in N3 sleep than other states. Region-specific cerebellar connectivity changes between N2 sleep and N3 sleep were also revealed: general breakdown of intra-cerebellar connectivity, enhancement of limbic-cerebellar connectivity and alterations of cerebellar connectivity with spatially specific neocortices. Further correlation analysis showed that functional connectivity between the cerebellar Control II network and regions (including the insula, hippocampus, and amygdala) correlated with delta power during N3 and beta power during N2 sleep. These findings systematically reveal altered cerebellar connectivity among intrinsic networks from wakefulness to deep sleep and highlight the potential role of the cerebellum in sleep regulation and functioning.


Asunto(s)
Neocórtex , Vigilia , Humanos , Vigilia/fisiología , Mapeo Encefálico , Electroencefalografía , Encéfalo/fisiología , Sueño/fisiología , Fases del Sueño/fisiología , Cerebelo/diagnóstico por imagen
13.
J Neurosci Res ; 101(6): 916-929, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36696411

RESUMEN

Deep brain stimulation (DBS) of the anterior nucleus of the thalamus (ANT) appears to be effective against seizures in animals and humans however, its therapeutic mechanisms remain elusive. This study aimed to combine 9.4T multimodal magnetic resonance imaging (MRI) with histology to investigate the longitudinal effects of long-term ANT-DBS in pilocarpine-induced epileptic rats. Status epilepsy (SE) was induced by LiCl-pilocarpine injection in 11 adult male Sprague-Dawley rats. Four weeks after SE, chronic epileptic rats underwent either ANT-DBS (n = 6) or sham-DBS (n = 5) surgery. Electroencephalography (EEG) and spontaneous recurrent seizures (SRS) were recorded for 1 week. The T2-weighted image and images from resting-state functional MRI (rs-fMRI) were acquired at three states: before SE, at 4 weeks post-SE, and at 5 weeks post-DBS. Volumes of the hippocampal subregions and hippocampal-related functional connectivity (FC) were compared longitudinally. Finally, antibodies against neuronal nuclei (NeuN) and glial fibrillary acidic proteins were used to evaluate neuronal loss and astrogliosis in the hippocampus. Long-term ANT-DBS significantly reduced seizure generalization in pilocarpine-induced epileptic rats. By analyzing the gray matter volume using T2-weighted images, long-term ANT-DBS displayed morphometric restoration of the hippocampal subregions. Neuronal protection of the hippocampal subregions and inhibition of astrogliosis in the hippocampal subregions were observed in the ANT-DBS group. ANT-DBS caused reversible regulation of FC in the insula-hippocampus and subthalamic nucleus-hippocampus. Long-term ANT-DBS provides comprehensive protection of hippocampal histology, hippocampal morphometrics, and hippocampal-related functional networks.


Asunto(s)
Estimulación Encefálica Profunda , Epilepsia , Humanos , Adulto , Ratas , Masculino , Animales , Pilocarpina/toxicidad , Pilocarpina/metabolismo , Gliosis/inducido químicamente , Gliosis/diagnóstico por imagen , Gliosis/metabolismo , Ratas Sprague-Dawley , Estimulación Encefálica Profunda/métodos , Epilepsia/inducido químicamente , Epilepsia/diagnóstico por imagen , Epilepsia/terapia , Convulsiones/metabolismo , Imagen por Resonancia Magnética , Hipocampo/metabolismo
14.
J Med Virol ; 95(6): e28846, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37282766

RESUMEN

Since the first SARS-CoV-2 outbreak in late 2019, the SARS-CoV-2 genome has harbored multiple mutations, especially spike protein mutations. The currently fast-spreading Omicron variant that manifests without symptoms or with upper respiratory diseases has been recognized as a serious global public health problem. However, its pathological mechanism is largely unknown. In this work, rhesus macaques, hamsters, and BALB/C mice were employed as animal models to explore the pathogenesis of Omicron (B.1.1.529). Notably, Omicron (B.1.1.529) infected the nasal turbinates, tracheae, bronchi, and lungs of hamsters and BALB/C mice with higher viral loads than in those of rhesus macaques. Severe histopathological damage and inflammatory responses were observed in the lungs of Omicron (B.1.1.529)-infected animals. In addition, viral replication was found in multiple extrapulmonary organs. Results indicated that hamsters and BALB/c mice are potential animal models for studies on the development of drugs/vaccines and therapies for Omicron (B.1.1.529).


Asunto(s)
COVID-19 , SARS-CoV-2 , Ratones , Animales , Cricetinae , Macaca mulatta , Ratones Endogámicos BALB C , Bronquios
15.
Cereb Cortex ; 32(19): 4141-4155, 2022 09 19.
Artículo en Inglés | MEDLINE | ID: mdl-35024797

RESUMEN

Human decision-making requires the brain to fulfill neural computation of benefit and risk and therewith a selection between options. It remains unclear how value-based neural computation and subsequent brain activity evolve to achieve a final decision and which process is modulated by irrational factors. We adopted a sequential risk-taking task that asked participants to successively decide whether to open a box with potential reward/punishment in an eight-box trial, or not to open. With time-resolved multivariate pattern analyses, we decoded electroencephalography and magnetoencephalography responses to two successive low- and high-risk boxes before open-box action. Referencing the specificity of decoding-accuracy peak to a first-stage processing completion, we set it as the demarcation and dissociated the neural time course of decision-making into valuation and selection stages. The behavioral hierarchical drift diffusion modeling confirmed different information processing in two stages, that is, the valuation stage was related to the drift rate of evidence accumulation, while the selection stage was related to the nondecision time spent in response-producing. We further observed that medial orbitofrontal cortex participated in the valuation stage, while superior frontal gyrus engaged in the selection stage of irrational open-box decisions. Afterward, we revealed that irrational factors influenced decision-making through the selection stage rather than the valuation stage.


Asunto(s)
Toma de Decisiones , Imagen por Resonancia Magnética , Encéfalo/fisiología , Mapeo Encefálico , Toma de Decisiones/fisiología , Humanos , Recompensa
16.
Cereb Cortex ; 32(11): 2478-2491, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-34643680

RESUMEN

Sex differences in human emotion and related decision-making behaviors are recognized, which can be traced back early in development. However, our understanding of their underlying neurodevelopmental mechanisms remains elusive. Using developmental functional magnetic resonance imaging and computational approach, we investigated developmental sex differences in latent decision-making dynamics during negative emotion processing and related neurocognitive pathways in 243 school-aged children and 78 young adults. Behaviorally, girls exhibit higher response caution and more effective evidence accumulation, whereas boys show more impulsive response to negative facial expression stimuli. These effects parallel sex differences in emotion-related brain maturity linking to evidence accumulation, along with age-related decrease in emotional response in the basolateral amygdala and medial prefrontal cortex (MPFC) in girls and an increase in the centromedial amygdala (CMA) in boys. Moreover, girls exhibit age-related decreases in BLA-MPFC coupling linked to evidence accumulation, but boys exhibit increases in CMA-insula coupling associated with response caution. Our findings highlight the neurocomputational accounts for developmental sex differences in emotion and emotion-related behaviors and provide important implications into the neurodevelopmental mechanisms of sex differences in latent emotional decision-making dynamics. This informs the emergence of sex differences in typical and atypical neurodevelopment of children's emotion and related functions.


Asunto(s)
Amígdala del Cerebelo , Caracteres Sexuales , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/fisiología , Niño , Emociones/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefrontal/fisiología , Adulto Joven
17.
Cereb Cortex ; 32(5): 1024-1039, 2022 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-34378030

RESUMEN

Functional brain networks require dynamic reconfiguration to support flexible cognitive function. However, the developmental principles shaping brain network dynamics remain poorly understood. Here, we report the longitudinal development of large-scale brain network dynamics during childhood and adolescence, and its connection with gene expression profiles. Using a multilayer network model, we show the temporally varying modular architecture of child brain networks, with higher network switching primarily in the association cortex and lower switching in the primary regions. This topographical profile exhibits progressive maturation, which manifests as reduced modular dynamics, particularly in the transmodal (e.g., default-mode and frontoparietal) and sensorimotor regions. These developmental refinements mediate age-related enhancements of global network segregation and are linked with the expression profiles of genes associated with the enrichment of ion transport and nucleobase-containing compound transport. These results highlight a progressive stabilization of brain dynamics, which expand our understanding of the neural mechanisms that underlie cognitive development.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Adolescente , Mapeo Encefálico , Corteza Cerebral , Niño , Cognición , Humanos , Imagen por Resonancia Magnética/métodos , Vías Nerviosas
18.
Arch Womens Ment Health ; 26(6): 803-817, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37730923

RESUMEN

Laboratory studies reveal that young women with premenstrual syndrome (PMS) often exhibit decreased reward processing during the late luteal phase. However, studies based on the self-reports find opposite results (e.g., higher craving for high-sweet-fat food). These differences may lie in the difference between the stimulus used and measuring the different aspects of the reward. The present study was designed to expand previous work by using a classic monetary reward paradigm, simultaneously examining the motivational (i.e., reward anticipation, "wanting") and emotional (i.e., reward outcome, "liking") components of reward processing in women with high premenstrual symptoms (High PMS). College female students in their early twenties with High PMS (n = 20) and low premenstrual symptoms (Low PMS, n = 20) completed a monetary incentive delay task during their late luteal phase when the premenstrual symptoms typically peak. Brain activities in the reward anticipation phase and outcome phase were recorded using the magnetoencephalographic (MEG) imaging technique. No group differences were found in various behavioral measurements. For the MEG results, in the anticipation phase, when High PMS participants were presented with cues that predicted the upcoming monetary gains, they showed higher event-related magnetic fields (ERFs) than when they were presented with neutral non-reward cues. This pattern was reversed in Low PMS participants, as they showed lower reward cue-elicited ERFs than non-reward cue-elicited ones (cluster mass = 2560, cluster size = 891, p = .03, corrected for multiple comparisons), mainly in the right medial orbitofrontal and lateral orbitofrontal cortex (cluster mass = 375, cluster size = 140, p = .03, corrected for multiple comparisons). More importantly, women with High PMS had an overall significantly higher level of ERFs than women with Low PMS (cluster mass = 8039, cluster size = 2937, p = .0009, corrected for multiple comparisons) in the bilateral precentral gyrus, right postcentral gyrus, and left superior temporal gyrus (right: cluster mass = 410, cluster size = 128, p = .03; left: cluster mass = 352, cluster size = 98, p = .05; corrected for multiple comparisons). In the outcome phase, women with High PMS showed significantly lower theta power than the Low PMS ones for the expected non-reward feedback in the bilateral temporal-parietal regions (cluster mass = 47620, cluster size = 18308, p = .01, corrected for multiple comparisons). These findings reveal that the severity of PMS might alter reward anticipation. Specifically, women with High PMS displayed increased brain activities to reward-predicting cues and increased action preparation after the cues appear.


Asunto(s)
Magnetoencefalografía , Síndrome Premenstrual , Femenino , Humanos , Síndrome Premenstrual/psicología , Encéfalo , Fase Luteínica , Recompensa
19.
J Neurosci ; 41(17): 3854-3869, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33687963

RESUMEN

The integral capacity of human language together with semantic memory drives the linkage of words and their meaning, which theoretically is subject to cognitive control. However, it remains unknown whether, across different language modalities and input/output formats, there is a shared system in the human brain for word-meaning binding and how this system interacts with cognitive control. Here, we conducted a functional magnetic resonance imaging experiment based on a large cohort of subjects (50 females, 50 males) to comprehensively measure the brain responses evoked by semantic processing in spoken and written word comprehension and production tasks (listening, speaking, reading, and writing). We found that heteromodal word input and output tasks involved distributed brain regions within a frontal-parietal-temporal network and focally coactivated the anterior lateral visual word form area (VWFA), which is located in the basal occipitotemporal area. Directed connectivity analysis revealed that the VWFA was invariably under significant top-down modulation of the frontoparietal control network and interacts with regions related to attention and semantic representation. This study reveals that the VWFA is a key site subserving general semantic processes linking words and meaning, challenging the predominant emphasis on this area's specific role in reading or more general visual processes. Our findings also suggest that the dynamics between semantic memory and cognitive control mechanisms during word processing are largely independent of the modalities of input or output.SIGNIFICANCE STATEMENT Binding words and their meaning into a coherent whole during retrieval requires accessing semantic memory and cognitive control, allowing our thoughts to be expressed and comprehended through mind-external tokens in multiple modalities, such as written or spoken forms. However, it is still unknown whether multimodal language comprehension and production share a common word-meaning binding system in human brains and how this system is connected to a cognitive control mechanism. By systematically measuring brain activity evoked by spoken and written verbal input and output tasks tagging word-meaning binding processes, we demonstrate a general word-meaning binding site within the visual word form area (VWFA) and how this site is modulated by the frontal-parietal control network.


Asunto(s)
Comprensión/fisiología , Lóbulo Frontal/fisiología , Lóbulo Parietal/fisiología , Lectura , Mapeo Encefálico , Cognición/fisiología , Femenino , Lóbulo Frontal/diagnóstico por imagen , Humanos , Lenguaje , Pruebas del Lenguaje , Imagen por Resonancia Magnética , Masculino , Memoria/fisiología , Vías Nerviosas/fisiología , Lóbulo Occipital/fisiología , Lóbulo Parietal/diagnóstico por imagen , Percepción del Habla/fisiología , Medición de la Producción del Habla , Adulto Joven
20.
Neuroimage ; 260: 119490, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35853543

RESUMEN

Spatial hearing in humans is a high-level auditory process that is crucial to rapid sound localization in the environment. Both neurophysiological models with animals and neuroimaging evidence from human subjects in the wakefulness stage suggest that the localization of auditory objects is mainly located in the posterior auditory cortex. However, whether this cognitive process is preserved during sleep remains unclear. To fill this research gap, we investigated the sleeping brain's capacity to identify sound locations by recording simultaneous electroencephalographic (EEG) and magnetoencephalographic (MEG) signals during wakefulness and non-rapid eye movement (NREM) sleep in human subjects. Using the frequency-tagging paradigm, the subjects were presented with a basic syllable sequence at 5 Hz and a location change that occurred every three syllables, resulting in a sound localization shift at 1.67 Hz. The EEG and MEG signals were used for sleep scoring and neural tracking analyses, respectively. Neural tracking responses at 5 Hz reflecting basic auditory processing were observed during both wakefulness and NREM sleep, although the responses during sleep were weaker than those during wakefulness. Cortical responses at 1.67 Hz, which correspond to the sound location change, were observed during wakefulness regardless of attention to the stimuli but vanished during NREM sleep. These results for the first time indicate that sleep preserves basic auditory processing but disrupts the higher-order brain function of sound localization.


Asunto(s)
Sueño de Onda Lenta , Localización de Sonidos , Animales , Electroencefalografía/métodos , Movimientos Oculares , Humanos , Sueño/fisiología , Fases del Sueño/fisiología , Vigilia/fisiología
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