International Journal of Neuroscience最新文献

Background: Alzheimer's disease (AD) and frontotemporal dementia (FTD) are neurodegenerative diseases with overlapping symptoms, complicating diagnosis. EEG-derived brain connectivity metrics, based on network neuroscience, can quantify brain network organization, but comparisons between AD and FTD using standardized EEG datasets are limited.

Methods: We analyzed a publicly available EEG dataset consisting of 36 AD patients, 23 FTD patients, and 29 healthy controls (HCs). Resting-state eyes-closed and eyes-open EEGs were analyzed across delta, theta, alpha, and beta bands. Phase-locking values (PLV) estimated functional connectivity between 19 electrodes, and graph-theory metrics were derived using the Brain Connectivity Toolbox. Group differences were assessed using ANOVAs with FDR correction, followed by Tukey tests.

Results: AD patients showed reduced global efficiency and small-worldness, especially in the alpha and beta bands under eyes-closed conditions, indicating decreased integration. FTD patients exhibited localized network disruptions in frontal and central regions, particularly reduced node degree and local efficiency at F3/F4 and Pz electrodes, suggesting region-specific dysfunction. These differences were more prominent in the eyes-closed state.

Conclusion: EEG graph-theory analysis revealed distinct network alterations in AD and FTD. AD showed impaired global integration and loss of small-world architecture, while FTD demonstrated region-specific disruptions. These findings suggest that EEG graph metrics may serve as cost-effective biomarkers for differentiating dementia subtypes and understanding disease-specific network dysfunction.

Background: Genetic polymorphisms in apoptosis-related genes FAS/FASL may influence susceptibility to glioma, but evidence remains limited, particularly in Chinese populations. This study aimed to investigate the potential association between gene polymorphisms in FAS (rs2234767, rs1800682) and FASL (rs763110, rs6700734) and glioma risk in a Chinese cohort.

Methods: This case-control study included 107 glioma patients and 110 healthy controls. Four polymorphisms were genotyped using TaqMan real-time PCR. The associations between these genetic variants and glioma risk were evaluated via logistic regression after adjusting for relevant covariates. Furthermore, subgroup analyses stratified by ethnicity, isocitrate dehydrogenase 1 (IDH1) R132H status, and histological grade were performed, along with a haplotype-based analysis.

Results: The FAS rs2234767 GA genotype was associated with a significantly reduced glioma risk compared to the GG genotype (adjusted OR = 0.461, 95% CI: 0.232-0.917, P = 0.027). This protective effect was particularly evident in the Han subgroup (adjusted OR = 0.275, 95% CI: 0.106-0.716, P = 0.008), IDH1 R132H-positive cases (adjusted OR = 0.362, 95% CI: 0.148-0.884, P = 0.026), and low-grade gliomas (adjusted OR = 0.350, 95% CI: 0.133-0.922, P = 0.034). No notable associations were observed for FASL variants. Haplotype analyses revealed no significant associations.

Conclusion: This study suggests a potential protective role of the FAS rs2234767 GA genotype against glioma in the Chinese population, particularly among Han individuals, IDH1 R132H-positive cases, and low-grade gliomas. The findings, while insightful, require validation in larger cohorts. Future research should integrate molecular profiling and functional assays to clarify the underlying mechanisms.

Background: High-density lipoprotein cholesterol (HDL-C)/apolipoprotein A-1 (APOA-1) ratio has been identified as a risk factor for cardiovascular disease, cancer, and all-cause mortality. However, data related to ischemic stroke (IS) are lacking. We investigated whether the HDL-C/APOA-1 ratio was associated with 3-month functional outcome in patients with IS.

Methods: A retrospective analysis was performed on 674 patients with IS. The 3-month functional outcome was classified as good or poor based on the modified Rankin Scale score (mRS). Logistic regression models (unadjusted and stepwise) were performed to evaluate the correlation between HDL-C/APOA-1 ratio and outcome. Restricted cubic splines evaluated nonlinear relationships, while subgroup analyses explored effect modifications. We assessed the added predictive value of the HDL-C/APOA-1 ratio by comparing nested models using the AUC, NRI, and IDI.

Results: The HDL-C/APOA-1 level in the group with poor functional outcomes was higher than that in the group with good functional outcomes (0.99 ± 0.14 vs. 0.94 ± 0.10, p < 0.001). In the multivariable analysis, a higher HDL-C/APOA-1 ratio was identified as an independent factor associated with poor outcome at 3 months (OR 1.50, 95% CI:1.17-1.96, p = 0.003). The odds of poor outcome in the higher HDL-C/APOA-1 quartile increased by 2.44-fold (95% CI:1.30-4.64, p = 0.006) after adjusting for potential confounders compared to lower HDL-C/APOA-1 quartiles. In addition, multivariate-adjusted restricted cubic splines show a positive approach linear pattern of this association.

Conclusion: Elevated HDL-C/APOA-1 is independently associated with an increased risk of poor functional outcomes at 3-month in patients with IS.

Background: Stroke and malnutrition remain significant contributors to preventable mortality in the United States. Stroke is a leading cause of death and disability, while malnutrition, often underrecognized, exacerbates neurological and systemic vulnerability. Characterizing long-term national and subgroup-specific mortality patterns is critical for guiding public health interventions.

Methods: Mortality data for stroke and malnutrition were analyzed from 1999 to 2023 using the CDC WONDER database. Age-adjusted mortality rates (AAMR) per 1,000,000 population were calculated and stratified by sex, race/ethnicity, census region, state and urbanization status. Joinpoint regression estimated average annual percent change (AAPC) with 95% confidence intervals (CIs).

Results: From 1999 to 2023, 44,368 deaths were attributed to malnutrition and stroke. The overall AAMR rose from 12.11 in 1999 to 14.75 in 2023, with an overall AAPC of 0.88% (95% CI: -0.14 to 1.91). Males had higher AAMRs than females. By race, Non Hispanic (NH) Black experienced the greatest AAMRs, whereas NH Asian had the lowest rates. Regionally, the South showed the highest rate, whereas Northeast had the lowest. Nonmetropolitan areas exceeded metropolitan areas. At the state level, the highest rates were observed in South Dakota and Arkansas, while Massachusetts recorded the lowest rates.

Conclusion: From 1999 to 2023, combined mortality from stroke and malnutrition increased modestly nationwide, with enduring disparities across demographics and geography. The highest burdens fell on NH Black individuals, people living in the South and nonmetropolitan areas, and certain central states. These findings highlight the need for region-specific prevention and better access to nutritional and neurological care.

Purpose/aim: The developing brain undergoes a remarkable process of synaptic changes.

Material and methods: To investigate the developmental changes in glutamatergic synaptic connections using the whole-cell patch clamp method, evoked excitatory postsynaptic currents (eEPSCs) were recorded from locus coeruleus (LC) neurons, a brain region crucial for cognitive functions, in rats at ages 7, 14, and 21 days. We employed fractal analysis to compute fractal dimensions of AMPA and NMDA receptors, serving as markers for synaptic maturation.

Results: Our findings revealed a significant increase in fractal dimensions during the third postnatal week and hence a developmental chenge of synaptic connections. A strong positive correlation between amplitude and fractal dimensions, in Pearson correlation analysis suggested that the synaptic currents' amplitude is closely related to the fractal properties of the receptors. A linear relationship between fractal dimensions and age indicated that fractal analysis can be a robust tool for predicting developmental changes. Additionally, we employed machine learning techniques to predict developmental changes based on AMPA and NMDA receptors. Support Vector Machine (SVM) models outperformed random forest models in accurately predicting age-dependent developmental changes, as indicated by the area under the curve (AUC) values. SVM achieved an AUC of 0.89 for AMPA receptors and 0.86 for NMDA receptors, demonstrating the effectiveness of fractal-based features in characterizing synaptic maturation.

Conclusion: This study offers valuable insights into synaptic development in the LC nucleus and demonstrates the potential of fractal analysis as a tool to understand brain plasticity and early development. Fractal dimensions play a crucial role in characterizing the maturation of glutamatergic synapses and neural circuitry development.

Background: Many medical students experience psychological distress from high academic demands, potentially harming their performance and mental health. Binaural beats (BB) stimulation, particularly gamma band entrainment, has been suggested to enhance neural communication, cognition, and reduce anxiety.

Objective: This study aimed to determine whether 40 Hz BB could improve cognitive performance and mood in medical students.

Method: Forty participants, selected based on the inclusion criteria of good health, normal hearing, and no mental illness were recruited considering factors such as all sessions availability and consent. Participants listened to BB for 15 min, three times a week, over three consecutive weeks. Electroencephalogram recordings confirmed that 40 Hz BB induced gamma neural oscillations in the brain. Emotional states were assessed using the 32-item Brunel Mood Scale (BRUMS) with ratings on a 5-point Likert scale, whereas cognitive function was measured with the Stroop's test, based on reaction time in milliseconds. Pre- and post-BB comparisons and gender-related differences were analyzed using paired and unpaired t-tests or appropriate non-parametric tests.

Result: Listening to BB significantly reduced negative emotions (p < 0.001), enhanced positive emotions (p < 0.001), and facilitated improvements in cognitive performance. However, the effects of BB were gender-specific, with female students showing greater improvements in 'happiness' and 'calmness', (p < 0.001), while males experienced more pronounced enhancements in cognitive performance (p < 0.001). Additionally, time-dependent effects of BB were also observed.

Conclusion: 40 Hz BB appears to be an effective tool for helping students manage their challenges calmly and more efficiently.

Aim: Depression is characterized by pervasive cognitive and emotional disturbances, yet the neural mechanisms underlying these deficits remain incompletely understood. Method: This study utilized multimodal neuroimaging, including resting-state functional MRI and structural T1-weighted imaging, alongside the MATRICS Consensus Cognitive Battery (MCCB) and the Hamilton Depression Rating Scale (HAMD), to delineate the structural and functional alterations in the insula in first-episode, medication-naïve patients with depression. Result: Compared to matched healthy controls, patients with depression exhibited significant reductions in gray matter density in the left insula, which were robustly associated with impairments in reasoning and problem-solving abilities. Mediation analyses revealed that insular gray matter density mediated the relationship between depressive symptom severity and cognitive deficits, emphasizing the insula's critical role in linking emotional and cognitive dysfunctions. Furthermore, functional connectivity analyses identified disrupted insula-medial prefrontal cortex circuits, highlighting their contribution to the pathophysiology of depression. Conclusion: These findings underscore the insula's dual role as a structural and functional hub in depression, advancing our understanding of the neural substrates of cognitive dysfunction and informing potential targets for intervention.

Objective: To identify the molecular targets of mesenchymal stem cell (MSC)-derived exosomes in treating cerebral ischemia and elucidate their therapeutic mechanisms.

Methods: We utilized a mouse model of middle cerebral artery occlusion and treated mice with umbilical cord mesenchymal stem cells derived exosomes. Proteomic analysis identified AAK1(AP2 associated kinase 1) as a key target protein. Functional studies confirmed that AAK1 modulates the NF-κB signaling pathway in ischemic stroke. MicroRNA profiling, bioinformatic prediction and cell experiments identified miR-664a-5p as the specific microRNA regulating AAK1 expression. Finally, we validated the therapeutic effects of umbilical cord mesenchymal stem cell-derived exosomes using engineered miR-664a-5p-deficient exosomes.

Results: Our findings demonstrate that umbilical cord mesenchymal stem cells-derived exosomes exert neuroprotective effects in ischemic stroke by modulating the AAK1/NF-κB axis via miR-664a-5p.

Conclusion: This study provides novel insights into the therapeutic mechanism of mesenchymal stem cell-derived exosomes in ischemic stroke, highlighting their potential for developing exosome-based therapies.

Objective: Gliomas are the most common primary tumors of the central nervous system. The fifth edition of the World Health Organization (WHO) Classification of Tumors of the CNS identifies IDH mutant astrocytomas grade 4 and IDH wild type glioblastomas grade 4 as distinct entities. This study aimed to identify morphological indicators that could predict IDH mutation status in grade 4 diffuse astrocytomas and grade 4 glioblastomas among fifty patients from two groups.Methods: Hematoxylin and eosin (H&E)-stained tumor slides were scanned using a digital scanner and further histopathological examinations were performed on digital images, with additional calculations and measurements.Results: The study showed that, IDH-wildtype glioblastomas and IDH-mutant grade 4 astrocytomas exhibit unique morphological features, particularly in relation to levels of necrosis, microvessel density, and the presence of "C" or "Ring" shape giant cells.Conclusion: Despite advancements in genomic biomarker technology, histology remains an essential tool for predicting patient outcomes. Therefore, pathologists must continue to investigate and document the morphological implications of molecular changes in CNS tumors.

Aim: The aim of this study was to assess the ameliorative effects of naringin (NR) on cognitive impairment in schizophrenia(SZ) from multiple perspectives using behavioral, histopathological and molecular biological approaches.

Materials and methods: SZ models were established in rats via acute intraperitoneal injection of MK-801 in all groups except the control group, which received saline. Cognitive function was assessed using the Morris water maze test 21 days after prophylactic NR administration. Subsequently, Serum interleukin-6 (IL-6) and homocysteine (HCY) levels were quantified using enzyme-linked immunosorbent assay (ELISA), and hippocampal neuronal and synaptic structures were observed via microscopy. Molecular detection was performed using real-time reverse transcription polymerase chain reaction (RT-qPCR) and western blotting (WB) to assess the expression levels of molecules related to the microRNA-25-3p/salt inducible kinase 1/CREB regulated transcription coactivator 2/cAMP responsive element binding protein 1 (miR-25-3p/SIK1/CRTC2/CREB1) pathway, thereby elucidating the mechanism by which NR ameliorates cognitive impairment in SZ.

Results: NR was found to mitigate cognitive decline in learning and memory induced by MK-801. It lowered serum levels of IL-6 and HCY, reduced neuronal damage in the CA1 region of the hippocampus, increased the thickness of postsynaptic dense material, decreased the distance between synaptic gaps, decreased the expression of SIK1, and elevated the expression of miR-25-3p, CRTC2 and CREB1 in the hippocampus.

Conclusion: NR may protect neurons in the CA1 region of the hippocampus and enhance synaptic plasticity by regulating the miR-25-3p/SIK1/CRTC2/CREB1 signaling pathway, thereby promoting cognitive improvement.