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1.
Chaos ; 33(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656915

RESUMO

Up to now, it still remains an open question about the relation between the structure of brain networks and their functions. The effects of structure on the dynamics of neural networks are usually investigated via extensive numerical simulations, while analytical analysis is always very difficult and thus rare. In this work, we explored the effects of a random regular graph on the dynamics of a neural network of stochastic spiking neurons, which has a bistable region when fully connected. We showed by numerical simulations that as the number of each neuron's neighbors decreases, the bistable region shrinks and eventually seems to disappear, and a critical-like transition appears. In the meantime, we made analytical analysis that explains numerical results. We hope this would give some insights into how structure affects the dynamics of neural networks from a theoretical perspective, rather than merely by numerical simulations.


Assuntos
Encéfalo , Redes Neurais de Computação , Neurônios
2.
Chaos ; 33(2): 023119, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36859226

RESUMO

The theory of self-organized bistability (SOB) is the counterpart of self-organized criticality for systems tuning themselves to the edge of bistability of a discontinuous phase transition, rather than to the critical point of a continuous one. As far as we are concerned, there are currently few neural network models that display SOB or rather its non-conservative version, self-organized collective oscillations (SOCO). We show that by slightly modifying the firing function, a stochastic excitatory/inhibitory network model can display SOCO behaviors, thus providing some insights into how SOCO behaviors can be generated in neural network models.

3.
Front Neural Circuits ; 17: 1308629, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239606

RESUMO

Topological data analysis is becoming more and more popular in recent years. It has found various applications in many different fields, for its convenience in analyzing and understanding the structure and dynamic of complex systems. We used topological data analysis to analyze the firings of a network of stochastic spiking neurons, which can be in a sub-critical, critical, or super-critical state depending on the value of the control parameter. We calculated several topological features regarding Betti curves and then analyzed the behaviors of these features, using them as inputs for machine learning to discriminate the three states of the network.


Assuntos
Aprendizado de Máquina , Neurônios , Neurônios/fisiologia
4.
Chaos ; 32(10): 103116, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36319307

RESUMO

A large amount of research has used the scale-free statistics of neuronal avalanches as a signature of the criticality of neural systems, which bears criticisms. For instance, the work of Touboul and Destexhe demonstrated that non-critical systems could also display such scale-free dynamics, which passed their rigorous statistical analyses. In this paper, we show that a fully connected stochastic neural network may also generate scale-free dynamics simply by jumping among many stable states.


Assuntos
Modelos Neurológicos , Neurônios , Potenciais de Ação/fisiologia , Neurônios/fisiologia , Redes Neurais de Computação
5.
Front Neural Circuits ; 16: 911245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669452

RESUMO

The study of the brain criticality hypothesis has been going on for about 20 years, various models and methods have been developed for probing this field, together with large amounts of controversial experimental findings. However, no standardized protocol of analysis has been established so far. Therefore, hoping to make some contributions to standardization of such analysis, we review several available tools used for estimating the criticality of the brain in this paper.


Assuntos
Encéfalo , Modelos Neurológicos
6.
Acta Biochim Pol ; 69(1): 165-172, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35143148

RESUMO

Abnormal expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 4 (PFKFB4) is closely related to the occurrence and development of tumors, and PFKFB4 has been shown to function as a protein kinase. However, the molecular mechanisms through which PFKFB4 functions in glioblastoma (GBM) remain poorly understood. Accordingly, in this study, we assessed the roles of PFKFB4 in GBM. Compared to in adjacent tissues, PFKFB4 was highly expressed in GBM, and its expression level was negatively correlated with the overall survival time. In addition, knockdown of PFKFB4 inhibited the proliferation and invasion of GBM cells and promoted apoptosis. In a xenograft tumor model, tumor growth was inhibited by knockdown of PFKFB4 using short hairpin RNA. Further studies demonstrated that PFKFB4 is involved in regulating the AKT signaling pathway. Thus, PFKFB4 acts as a protein kinase to regulate GBM progression by activating the AKT/forkhead box O1 pathway, which may be a potential therapeutic target in GBM.


Assuntos
Proteína Forkhead Box O1/metabolismo , Glioblastoma/metabolismo , Fosfofrutoquinase-2/metabolismo , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Técnicas de Silenciamento de Genes/métodos , Glioblastoma/genética , Glicólise , Humanos , Masculino , Camundongos , Fosfofrutoquinase-2/genética , RNA Interferente Pequeno/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
7.
Medicine (Baltimore) ; 99(45): e23087, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33157978

RESUMO

BACKGROUND: Glioma is the most common type of brain tumor because of the destructiveness of the disease itself and the side effects of treatment, patients often leave symptoms of neurological defects. At present, rehabilitation treatment is not popular in glioma patients. There is a lack of definite evidence to prove the benefits of rehabilitation therapy for glioma patients. The purpose of this meta-analysis is to determine whether rehabilitation therapy can significantly improve the prognosis of neurological function and improve the quality of life of patients with glioma. METHODS: The articles about rehabilitation treatment of glioma in Cochrane, PubMed, and Embase, Web of Science, and Medline database from January 1990 to May 2020 were searched. Before rehabilitation as the control group, after rehabilitation as the experimental group. The Functional Independence Measure (FIM) was used as the outcome index, including total FIM, motor FIM, and cognitive FIM. Use STATA12.0 for meta-analysis. RESULTS: A total of 8 articles were included in the study, with a total of 375 glioma patients. Meta-analysis of total FIM (SMD = 0.96, 95%CI = 0.66-1.26, P < .001), motor FIM (SMD = 0.75, 95%CI = 0.54-0.96, P < .001) and cognitive FIM (SMD = 0.35, 95%CI = 0.19-0.50, P < .001) indicated that the neurological function of rehabilitation was significantly improved in total, motor and consciousness. CONCLUSION: The published studies show that rehabilitation therapy can improve the functional prognosis and quality of life of glioma patients. More attention should be paid to the therapeutic value of rehabilitation for glioma patients in the future. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42020188740.


Assuntos
Neoplasias Encefálicas/reabilitação , Glioma/reabilitação , Humanos , Qualidade de Vida , Resultado do Tratamento
8.
Open Life Sci ; 14: 659-665, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33817205

RESUMO

Neutrophil is a key element in inflammation and stress disease, which are associated with poor clinical outcomes in various cardiac diseases. However, the clinical availability of neutrophil in patients with ST-elevation myocardial infarction (STEMI) and chronic renal dysfunction has not been known. Accordingly, we designed this retrospective cohort study to evaluate the differences of major adverse cardiovascular events incidence between renal dysfunctional STEMI patients with normal and high neutrophil levels. The primary end point was all-cause mortality. We analyzed 377 consecutive STEMI patients with chronic renal dysfunction. The results showed that during 12-48 months follow-up, death from any-cause occurred in 1.4% patients (4 of 290) in normal-level neutrophil group, as compared with 3.4% in high-level neutrophil group (3 of 87) (hazard ratio, 2.174 95% confidence interval, 1.024-10.248; P = 0.025). Kaplan-Meier survival analysis showed that there were significant differences between the two groups with respect to the risk of death (P=0.018), and heart failure (P=0.037).

9.
Int J Clin Exp Med ; 8(9): 15657-65, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26629060

RESUMO

BACKGROUND: Coronary artery disease (CAD) is a major health problem in global. Benefit from different care unit for various type of CAD is remaining unknown. We investigate if coronary care unit (CCU) reduces the incidence of major adverse cardiovascular events (MACEs). METHOD: 806 CAD patients including stable angina (SA) and acute coronary syndrome (ACS) who treated in department of cardiology were involved in the study as two groups. Each group involved two subgroups according to the therapy unit including CCU and normal unit. 12-48 months follow-up was carried out. The primary end point was all cause mortality. RESULTS: For SA, death from any cause occurred in 1.0% of the patients in the normal group (1 of 108), as compared with 5.1% in the CCU group (3 of 59) (hazard ratio [HR], 0.164; 95% confidence interval [CI], 0.017 to 1.580; P=0.118). Kaplan-Meier survival analysis showed that there were no significant differences between the two subgroups with respect to the risk of death (P=0.074), revascularization (P=0.660), stroke (P=0.497), heart failure (P=0.658) and hemorrhage (P=0.096). For ACS, death occurred in 1.9% of the patients in the normal subgroup (5 of 267), as compared with 1.3% in the CCU subgroup (5 of 372) (HR, 1.403; 95% CI, 0.406-4.846; P=0.593). Kaplan-Meier survival analysis showed that there were no significant differences between the two subgroups with respect to the risk of death (P=0.591), revascularization (P=0.996), stroke (P=0.425), heart failure (P=0.625). CONCLUSION: CAD patients treated in CCU obtain little benefits compared with normal.

10.
Int J Clin Exp Med ; 8(10): 18335-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26770436

RESUMO

Coronary care unit is common in hospitals and clinical centers which offer intensive care and therapy for severe coronary artery disease patients. However, if coronary care unit could improve the long term prognosis of acute coronary syndrome patients with renal dysfunction remain unknown. Accordingly, we designed this study to evaluate the differences of incidence of major adverse cardiovascular events for acute coronary syndromes patients with renal dysfunction who treated in coronary care unit or normal unit. The primary end point was all cause mortality. A total of 414 acute coronary syndromes patients with renal dysfunction involved in the study. The results showed that during 12-48 months follow-up, death of any cause occurred in 1.8% patients (4 of 247) in coronary care unit group, as compared with 1.8% in the normal group (3 of 167) (hazard ratio, 1.098; 95% confidence interval, 0.246 to 4.904; P=0.903). Kaplan-Meier survival analysis showed that there were no significant differences between the two groups with respect to the risk of death (P=0.903), revascularization (P=0.948), stroke (P=0.542), heart failure (P=0.198). This trial firstly revealed that acute coronary syndromes patients with renal dysfunction treated in coronary care unit and normal units. Our study showed that acute coronary syndromes patients with renal dysfunction treated in coronary care unit obtained no significant benefits compared with patients in normal units, although there was a declining tendency of the risk of major adverse cardiovascular effectswith patients in coronary care unit.

11.
J Clin Med Res ; 6(6): 443-50, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25247018

RESUMO

BACKGROUND: The aim of this study was to investigate the relationship between serum uric acid and renal function, expressed as estimated glomerular filtration rate (eGFR), in patients with stable coronary artery disease (CAD) and type 2 diabetes mellitus (T2DM) in China. METHODS: Serum levels of uric acid and creatinine were determined in 526 enrolled patients diagnosed with stable CAD and T2DM. To assess renal function, eGFR was calculated using a modified MDRD formula suitable for the Chinese population. Patients' anthropometric measurements were collected using standardized protocols, and 6-month follow-up results were collected and analyzed. Pearson's correlation coefficient r was calculated and multivariate analysis was performed to evaluate the relationship between uric acid and renal function. Patients with eGFR < 60 mL/min/1.73 m(2) were classified as having reduced renal function or chronic kidney disease (CKD) in this study. RESULTS: Uric acid levels were negatively associated with eGFR (P = 0.002), especially in patients with CKD (eGFR < 60 mL/min/1.73 m(2)) (P < 0.001). In patients with reduced renal function, the risk in the highest quartile of uric acid levels was higher than in the lowest quartile (odds ratio 9.18, 95% confidence interval: 4.01 - 21.01, P < 0.001). These associations remained after multiple adjustments for potential confounders and were recapitulated after 6-month follow-up. CONCLUSIONS: Serum uric acid level is negatively associated with renal function, as assessed by eGFR, and serves as an independent predictor for CKD in patients with stable CAD and T2DM.

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