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1.
Neural Regen Res ; 20(2): 326-342, 2025 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38819037

RESUMO

Alzheimer's disease is a neurodegenerative disease resulting from deficits in synaptic transmission and homeostasis. The Alzheimer's disease brain tends to be hyperexcitable and hypersynchronized, thereby causing neurodegeneration and ultimately disrupting the operational abilities in daily life, leaving patients incapacitated. Repetitive transcranial magnetic stimulation is a cost-effective, neuro-modulatory technique used for multiple neurological conditions. Over the past two decades, it has been widely used to predict cognitive decline; identify pathophysiological markers; promote neuroplasticity; and assess brain excitability, plasticity, and connectivity. It has also been applied to patients with dementia, because it can yield facilitatory effects on cognition and promote brain recovery after a neurological insult. However, its therapeutic effectiveness at the molecular and synaptic levels has not been elucidated because of a limited number of studies. This study aimed to characterize the neurobiological changes following repetitive transcranial magnetic stimulation treatment, evaluate its effects on synaptic plasticity, and identify the associated mechanisms. This review essentially focuses on changes in the pathology, amyloidogenesis, and clearance pathways, given that amyloid deposition is a major hypothesis in the pathogenesis of Alzheimer's disease. Apoptotic mechanisms associated with repetitive transcranial magnetic stimulation procedures and different pathways mediating gene transcription, which are closely related to the neural regeneration process, are also highlighted. Finally, we discuss the outcomes of animal studies in which neuroplasticity is modulated and assessed at the structural and functional levels by using repetitive transcranial magnetic stimulation, with the aim to highlight future directions for better clinical translations.

2.
Geroscience ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727873

RESUMO

Electroencephalography (EEG) microstates are used to study cognitive processes and brain disease-related changes. However, dysfunctional patterns of microstate dynamics in Alzheimer's disease (AD) remain uncertain. To investigate microstate changes in AD using EEG and assess their association with cognitive function and pathological changes in cerebrospinal fluid (CSF). We enrolled 56 patients with AD and 38 age- and sex-matched healthy controls (HC). All participants underwent various neuropsychological assessments and resting-state EEG recordings. Patients with AD also underwent CSF examinations to assess biomarkers related to the disease. Stepwise regression was used to analyze the relationship between changes in microstate patterns and CSF biomarkers. Receiver operating characteristics analysis was used to assess the potential of these microstate patterns as diagnostic predictors for AD. Compared with HC, patients with AD exhibited longer durations of microstates C and D, along with a decreased occurrence of microstate B. These microstate pattern changes were associated with Stroop Color Word Test and Activities of Daily Living scale scores (all P < 0.05). Mean duration, occurrences of microstate B, and mean occurrence were correlated with CSF Aß 1-42 levels, while duration of microstate C was correlated with CSF Aß 1-40 levels in AD (all P < 0.05). EEG microstates are used to predict AD classification with moderate accuracy. Changes in EEG microstate patterns in patients with AD correlate with cognition and disease severity, relate to Aß deposition, and may be useful predictors for disease classification.

3.
J Alzheimers Dis ; 99(4): 1349-1359, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38820018

RESUMO

Background: Alzheimer's disease (AD) is a neurodegenerative disease characterized by brain network dysfunction. Few studies have investigated whether the functional connections between executive control networks (ECN) and other brain regions can predict the therapeutic effect of repetitive transcranial magnetic stimulation (rTMS). Objective: The purpose of this study is to examine the relationship between the functional connectivity (FC) within ECN networks and the efficacy of rTMS. Methods: We recruited AD patients for rTMS treatment. We established an ECN using baseline period fMRI data and conducted an analysis of the ECN's FC throughout the brain. Concurrently, the support vector regression (SVR) method was employed to project post-rTMS cognitive scores, utilizing the connectional attributes of the ECN as predictive markers. Results: The average age of the patients was 66.86±8.44 years, with 8 males and 13 females. Significant improvement on most cognitive measures. We use ECN connectivity and brain region functions in baseline patients as features for SVR model training and fitting. The SVR model could demonstrate significant predictability for changes in Montreal Cognitive Assessment scores among AD patients after rTMS treatment. The brain regions that contributed most to the prediction of the model (the top 10% of weights) were located in the medial temporal lobe, middle temporal gyrus, frontal lobe, parietal lobe and occipital lobe. Conclusions: The stronger the antagonism between ECN and parieto-occipital lobe function, the better the prediction of cognitive improvement; the stronger the synergy between ECN and fronto-temporal lobe function, the better the prediction of cognitive improvement.


Assuntos
Doença de Alzheimer , Função Executiva , Imageamento por Ressonância Magnética , Estimulação Magnética Transcraniana , Humanos , Doença de Alzheimer/terapia , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Masculino , Feminino , Idoso , Estimulação Magnética Transcraniana/métodos , Função Executiva/fisiologia , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Resultado do Tratamento , Testes Neuropsicológicos , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia
4.
Chemistry ; 29(14): e202202744, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36446736

RESUMO

Among the factors that lead to the reduction of the efficiency of perovskite solar cells (PSCs) the difficulty involved in realizing a high-quality film and the efficient charge transfer that takes place at the interface between electron-transport layer (ETL) and perovskite is worth mentioning. Here, a strategy for planar-type devices by natural bio-functional interfaces that uses a buried electron-transport layer made of cobalamin complexed tin oxide (SnO2 @B12 ) is demonstrated. Having systematically investigated the effects of SnO2 @B12 interfacial layer in perovskite solar cells, it can be concluded that cobalamin can chemically link the SnO2 layer and the perovskite layer, resulting in improved perovskite film quality and interfacial defect passivation. Utilizing SnO2 @B12 improves the efficiency of planar-type PSCs by 20.60 %. Furthermore, after 250 h of exposure to an ambient atmosphere, unsealed PSCs containing SnO2 @B12 degrade by 10 %. This research provides a viable method for developing bio-functional molecules that will increase the effectiveness and durability of planar-perovskite solar cells.

5.
J Neurol Surg A Cent Eur Neurosurg ; 78(4): 374-379, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28320030

RESUMO

Background Acute stroke causes intense and significant changes in the immune system as well as in the number and the ratio of various immune cells. Material and Methods Several large-scale studies have shown that ischemic stroke leaves the human body in a state of immunodepression. The regulatory T (Treg) cells may be strongly associated with a change of immune status. In this trial, we collected venous blood from a cohort of patients who were diagnosed with acute ischemic stroke within the last 24 hours (n = 139). We obtained their Treg cells/CD4+ T-cell ratio (Treg%) on days 1, 3, 7, and 14 using flow cytometry. Results We divided the patients into groups A and B based on the cerebral infarct volume being lesser or greater than 28.6 mL (the median infarct volume), respectively (calculated using the Pullicino formula). We also divided them per the trial of ORG 10172 in acute stroke treatment (TOAST) criteria. Compared with the controls, group A patients showed a slight increase on day 1 and an increase on days 3, 7, and 14 (p < 0.05). group B patients showed a decrease on days 1 and 3 and an increase on days 7 and 14 (p < 0.05). Group B patients showed higher infection rates than group A patients. We used repeated analysis of variance to confirm that gender, cerebral hemisphere, and infection had no influence on the frequency of Treg cells. Conclusion Our findings indicate that the Treg cells/CD4+ T-cell ratios undergo different changes in frequency in small- and large-volume strokes.


Assuntos
Isquemia Encefálica/imunologia , Linfócitos T CD4-Positivos/imunologia , Acidente Vascular Cerebral/imunologia , Linfócitos T Reguladores/imunologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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