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1.
IEEE Trans Neural Netw Learn Syst ; 34(7): 3501-3515, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34637381

RESUMO

This article investigates the problem of relaxed exponential stabilization for coupled memristive neural networks (CMNNs) with connection fault and multiple delays via an optimized elastic event-triggered mechanism (OEEM). The connection fault of the two or some nodes can result in the connection fault of other nodes and cause iterative faults in the CMNNs. Therefore, the method of backup resources is considered to improve the fault-tolerant capability and survivability of the CMNNs. In order to improve the robustness of the event-triggered mechanism and enhance the ability of the event-triggered mechanism to process noise signals, the time-varying bounded noise threshold matrices, time-varying decreased exponential threshold functions, and adaptive functions are simultaneously introduced to design the OEEM. In addition, the appropriate Lyapunov-Krasovskii functionals (LKFs) with some improved delay-product-type terms are constructed, and the relaxed exponential stabilization and globally uniformly ultimately bounded (GUUB) conditions are derived for the CMNNs with connection fault and multiple delays by means of some inequality processing techniques. Finally, two numerical examples are provided to illustrate the effectiveness of the results.


Assuntos
Redes Neurais de Computação , Fatores de Tempo
2.
IEEE Trans Cybern ; 53(3): 1485-1498, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34495857

RESUMO

This article is concerned with the exponential synchronization of coupled memristive neural networks (CMNNs) with multiple mismatched parameters and topology-based probability impulsive mechanism (TPIM) on time scales. To begin with, a novel model is designed by taking into account three types of mismatched parameters, including: 1) mismatched dimensions; 2) mismatched connection weights; and 3) mismatched time-varying delays. Then, the method of auxiliary-state variables is adopted to deal with the novel model, which implies that the presented novel model can not only use any isolated system (regard as a node) in the coupled system to synchronize the states of CMNNs but also can use an external node, that is, not affiliated to the coupled system to synchronize the states of CMNNs. Moreover, the TPIM is first proposed to efficiently schedule information transmission over the network, possibly subject to a series of nonideal factors. The novel control protocol is more robust against these nonideal factors than the traditional impulsive control mechanism. By means of the Lyapunov-Krasovskii functional, robust analysis approach, and some inequality processing techniques, exponential synchronization conditions unifying the continuous-time and discrete-time systems are derived on the framework of time scales. Finally, a numerical example is provided to illustrate the effectiveness of the main results.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36427282

RESUMO

This article focuses on the intralayer-dependent impulsive synchronization of multiple mismatched multilayer neural networks (NNs) with mode-mixed effects. Initially, a novel multilayer NN model that removes the one-to-one interlayer coupling constraint and introduces nonidentical model parameters is first established to meet diverse modeling requirements in complex applications. To help the multilayer target NNs with mismatched connection coefficients and time delays achieve synchronization, the hybrid controller is designed using intralayer-dependent impulsive control and switched feedback control approaches. Furthermore, the mode-mixed effects caused by the intralayer coupling delays and switched intralayer topologies are incorporated into the novel model and analysis method to ensure that the subsystems operating within the current switching interval can effectively use the topology information of the previous switching intervals. Then, a novel analysis framework including super-Laplacian matrix, augmented matrix, and mode-mixed methods is developed to derive the synchronization results. Finally, the main results are verified via the numerical simulation with secure communication.

4.
Diagnostics (Basel) ; 12(7)2022 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-35885560

RESUMO

In recent years, deep learning has been applied to many medical imaging fields, including medical image processing, bioinformatics, medical image classification, segmentation, and prediction tasks. Computer-aided detection systems have been widely adopted in brain tumor classification, prediction, detection, diagnosis, and segmentation tasks. This work proposes a novel model that combines the Bayesian algorithm with depth-wise separable convolutions for accurate classification and predictions of brain tumors. We combine Bayesian modeling learning and Convolutional Neural Network learning methods for accurate prediction results to provide the radiologists the means to classify the Magnetic Resonance Imaging (MRI) images rapidly. After thorough experimental analysis, our proposed model outperforms other state-of-the-art models in terms of validation accuracy, training accuracy, F1-score, recall, and precision. Our model obtained high performances of 99.03% training accuracy and 94.32% validation accuracy, F1-score, precision, and recall values of 0.94, 0.95, and 0.94, respectively. To the best of our knowledge, the proposed work is the first neural network model that combines the hybrid effect of depth-wise separable convolutions with the Bayesian algorithm using encoders.

5.
ISA Trans ; 122: 218-231, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33993995

RESUMO

In this study, an asynchronous H∞ state feedback controller is devised for Markov jump discrete-time systems (MJDTSs) with time-varying delay. "Asynchronous" means that the system switching mode θk, the controller mode ϑk and the quantizer mode λk are different from each other. The first one is homogeneous and the last two are non-homogeneous. In particular, as a promotion of existing work, we firstly attempt to propose the transition probabilities (TPs) of the three Markov chains (MCs) are not completely known. In addition, the discrete time-varying delay and its infinitely distributed ones are considered. Moreover, according to the Lyapunov stability theory and stochastic process, it is established for the sufficient criterion to ensure the stochastic stability of resulting closed-loop MJDTSs with an H∞ attenuation performance index. The feasibility and effectiveness of the proposed method are validated by three examples.

6.
IEEE Trans Neural Netw Learn Syst ; 32(1): 308-321, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217485

RESUMO

This article investigates the problem of robust exponential stability of fuzzy switched memristive inertial neural networks (FSMINNs) with time-varying delays on mode-dependent destabilizing impulsive control protocol. The memristive model presented here is treated as a switched system rather than employing the theory of differential inclusion and set-value map. To optimize the robust exponentially stable process and reduce the cost of time, hybrid mode-dependent destabilizing impulsive and adaptive feedback controllers are simultaneously applied to stabilize FSMINNs. In the new model, the multiple impulsive effects exist between two switched modes, and the multiple switched effects may also occur between two impulsive instants. Based on switched analysis techniques, the Takagi-Sugeno (T-S) fuzzy method, and the average dwell time, extended robust exponential stability conditions are derived. Finally, simulation is provided to illustrate the effectiveness of the results.


Assuntos
Lógica Fuzzy , Redes Neurais de Computação , Algoritmos , Simulação por Computador , Retroalimentação , Modelos Teóricos
7.
Front Genet ; 11: 574145, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281873

RESUMO

Retinoblastoma (RB) is the most common intraocular tumor in childhood. Long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NTAT1) has been reported to be related to RB progression. This study aims to study the molecular mechanism of NEAT1 in regulating cell cycle, proliferation, apoptosis, migration, and invasion in RB. The expression levels of NEAT1 and miR-3619-5p were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of LIM and SH3 domain protein 1 (LASP1) was measured by western blot. The proliferation of RB cells was analyzed by cell counting kit-8 (CCK-8) and cell colony formation assays. Cell migration and invasion were evaluated by transwell assay. Cell cycle and apoptosis were assessed by flow cytometry analysis. The association between miR-3619-5p and NEAT1 or LASP1 was predicted by starBase 3.0 database and identified by dual-luciferase reporter assay. The effects of NEAT1 knockdown on the tumor growth in vivo were detected by in vivo tumor formation assay. NEAT1 expression was dramatically up-regulated, and miR-3619-5p expression was obviously downregulated in RB tissues and cells compared with control groups. The protein level of LASP1 was obviously increased in RB tissues or cells relative to paracancerous normal tissues or cells, respectively. Functionally, NEAT1 silencing inhibited RB cell migration, invasion, and proliferation, whereas induced cell apoptosis and cell cycle arrest in RB; this phenomenon was partially abolished by miR-3619-5p inhibitor. Mechanistically, NEAT1 acted as a sponge of miR-3619-5p, and miR-3619-5p was associated with LASP1. In addition, NEAT1 knockdown decreased the volume and weight of RB tumor in vivo. Together, NEAT1 silencing repressed cell migration, invasion, and proliferation, whereas induced cell apoptosis and cycle arrest by sponging miR-3619-5p to inhibit LASP1 expression in RB cells. This study may provide a theoretical basis for RB therapy.

8.
Neural Netw ; 131: 242-250, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32823032

RESUMO

This paper investigates the exponential synchronization issue of stochastic delayed memristive neural networks (SDMNNs) via a novel hybrid control (HC), where impulsive instants are determined by the state-dependent trigger condition. The switching and quantification strategies are applied to the event-based impulsive controller to cope with the challenges induced concurrently by interval parameters, impulses, stochastic disturbance and time-varying delays. Furthermore, the control costs can be reduced and communication channels and bandwidths can be saved by using this designed controller. Then, novel Lyapunov functions and new analytical methods are constructed, which can be used to realize the exponential synchronization of SDMNNs via HC. Finally, a numerical simulation is provided to demonstrate our theoretical results.


Assuntos
Redes Neurais de Computação , Processos Estocásticos , Fatores de Tempo
9.
J Cell Physiol ; 234(6): 8873-8887, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30515784

RESUMO

Retinal neovascularization occurs in various ocular disorders including proliferative diabetic retinopathy and secondary neovascular glaucoma, resulting in blindness. This paper aims to investigate the effect of microRNA-141-3p (miR-141-3p) on retinal neovascularization and retinal ganglion cells (RGCs) in glaucoma mice through the Docking protein 5 (DOK5)-mediated mitogen-activated protein kinase (MAPK) signaling pathway. Chip retrieval and difference analysis were used for the potential mechanism of miR-141-3p on glaucoma. All modeled mice were transfected with different expression of mimic or inhibitor. The expressions of miR-141-3p, DOK5, and related genes and proteins of the MAPK signaling pathway were detected by Reverse transcription quantitative polymerase chain reaction and western blot analysis. Cell proliferation, lumen formation, and apoptosis in the retinal vascular epithelial cells and RGCs were detected using Matrigel angiogenesis and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling assays. Moreover, a total of 63 and 294 differentially expressed genes were obtained in GSE2378 and GSE9944 chips, and 4 genes were within the intersection of the chips. In addition, the results showed that miR-141-3p was found to inhibit the DOK5 gene and activate the MAPK pathway. The number of RGCs, the expression of p38, extracellular-signal-regulated kinases (ERK), Jun N-terminal kinase (JNK), IGF-1, VEGF, HIF1-α, Bax, caspase-3, and the extent of p38, ERK, and JNK phosphorylated were decreased with miR-141-3p upregulation. Lastly, the results obtained showed that miR-141-3p inhibited the proliferation of retinal vascular epithelial cells and inhibited angiogenesis, as well as promoted apoptosis of RGCs. The study suggests that miR-141-3p inhibits retinal neovascularization in glaucoma mice by impeding the activation of the DOK5-mediated MAPK signaling pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glaucoma/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , MicroRNAs/metabolismo , Células Ganglionares da Retina/metabolismo , Neovascularização Retiniana/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose/fisiologia , Proliferação de Células , Células Epiteliais/fisiologia , Regulação da Expressão Gênica/fisiologia , Glaucoma/patologia , Camundongos , MicroRNAs/genética
10.
Oncol Rep ; 40(6): 3155-3170, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30272300

RESUMO

Juvenile myelomonocytic leukemia (JMML) is a rare but severe primary hemopoietic system tumor of childhood, most frequent in children 4 years and younger. There are currently no specific anticancer therapies targeting JMML, and the underlying gene expression changes have not been revealed. To define molecular targets and possible biomarkers for early diagnosis, optimal treatment, and prognosis, we conducted microarray data analysis using the Gene Expression Omnibus, and constructed protein­protein interaction networks of all differentially expressed genes. Modular bioinformatics analysis revealed four core functional modules for JMML. We analyzed the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway functions associated with these modules. Using the CMap database, nine potential anticancer drugs were identified that modulate expression levels of many JMML­associated genes. In addition, we identified possible miRNAs and transcription factors regulating these differentially expressed genes. This study defines a new research strategy for developing JMML­targeted chemotherapies.


Assuntos
Antineoplásicos/farmacologia , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Leucemia Mielomonocítica Juvenil/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Bibliotecas de Moléculas Pequenas/farmacologia , Antineoplásicos/uso terapêutico , Pré-Escolar , Biologia Computacional/métodos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Predisposição Genética para Doença , Humanos , Lactente , Leucemia Mielomonocítica Juvenil/tratamento farmacológico , Leucemia Mielomonocítica Juvenil/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mapas de Interação de Proteínas , Bibliotecas de Moléculas Pequenas/uso terapêutico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
J Glaucoma ; 25(1): 62-94, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25304275

RESUMO

AIM: There were several studies that have researched the associations between lysyl oxidase-like 1 (LOXL1) gene polymorphism and the susceptibility to exfoliation syndrome (XFS)/exfoliation glaucoma (XFG), but results have been inconclusive. MATERIALS AND METHODS: A meta-analysis was performed for deriving more exact estimation of the relationship. Twenty-five studies were selected for studying rs1048661 and rs3825942. Sixteen studies were selected for studying rs2165241. RESULTS: Single nucleotide polymorphism (SNP) rs1048661 was found to be associated with XFS/XFG, but the risk allele in white populations was found to be G, as opposite to the T allele in Japanese, Chinese, and Korean populations. The SNP rs3825942 was significantly associated with XFS in this black South African population. However, the AA genotype of rs3825942 confers XFS risk in this population, as opposed to the GG genotype described in all other populations. SNP rs2165241 was found to be associated with XFS/XFG, but the risk allele in white populations was found to be T, as opposite to the "C" allele in Japanese and Korean populations. CONCLUSIONS: Our meta-analysis indicates that rs1048661 ("G" alleles) had weak association with XFG/XFS; rs3825942 ("G" alleles) had strongly association with XFG/XFS; and rs2165241("T" alleles) had significant risk with XFG/XFS in some ethnicity.


Assuntos
Aminoácido Oxirredutases/genética , Síndrome de Exfoliação/genética , Glaucoma de Ângulo Aberto/genética , Polimorfismo de Nucleotídeo Único , Alelos , Etnicidade , Síndrome de Exfoliação/etnologia , Genótipo , Glaucoma de Ângulo Aberto/etnologia , Haplótipos , Humanos , Pressão Intraocular , Pessoa de Meia-Idade
12.
Zhonghua Yan Ke Za Zhi ; 49(9): 835-40, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24330935

RESUMO

OBJECTIVES: To assess the permeability of Danshensu at blood-ocular barrier and its characteristics of pharmacokinetics by respectively measuring the concentrations of Danshensu in blood plasma and aqueous humor of the rabbit with the high performance liquid chromatography(HPLC). METHODS: It was an experimental study. Seventy-two white rabbits were split into three groups: control group (6 rabbits), plasma group (6 rabbits) and aqueous humor group (60 rabbits). After 0.85% salt water (control group)or salvia miltiorrhiza (1.0 g/kg) (plasma and aqueous group) was injected into the vein of auris-edge. Samples of blood and aqueous humor were obtained for analysis . The analytical column was a BDS C18 stainless steed column(5 µm, 4.6 mm× 250 mm); Precolumn:YWGC18; the mobile phase consists of acetonitrile and 0.01 mol/L KH2PO4 (8:92, adjusted to pH = 2.8 with phosphoric acid). The UV detector was set at 279 nm; the flow rate was 1.0 ml/min;and the column temperature was ordinary temperature. RESULTS: The plasma concentration-time curves of Salvia miltiorrhiza fitted three-compartment model. t1/2 ß (elimination half time): 5.661 min; Cmax (peak concentration): 727.29 mg/L; Tmax(peak time ): 0 min. The aqueous humor concentration-time curves fitted two-compartment model. t1/2 ß: 147.663 min; Cmax: 38.62 mg/L; Tmax: 25 min. CONCLUSIONS: HPLC is a sensitive, specific and accurate method that can be used in pharmacokinetics research on ocular tissue of rabbit for Danshensu, Salvia miltiorrhiza that is dissolvable in water can pass through the blood-ocular barrier after intravenous injection with a relatively stable concentration of danshensu in aqueous humor resulting from a slow rate of removal.


Assuntos
Humor Aquoso/metabolismo , Medicamentos de Ervas Chinesas/farmacocinética , Lactatos/farmacocinética , Salvia miltiorrhiza/química , Animais , Injeções Intravenosas , Lactatos/sangue , Coelhos
13.
BMC Plant Biol ; 13: 83, 2013 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-23688397

RESUMO

BACKGROUND: The PLAnt co-EXpression database (PLANEX) is a new internet-based database for plant gene analysis. PLANEX (http://planex.plantbioinformatics.org) contains publicly available GeneChip data obtained from the Gene Expression Omnibus (GEO) of the National Center for Biotechnology Information (NCBI). PLANEX is a genome-wide co-expression database, which allows for the functional identification of genes from a wide variety of experimental designs. It can be used for the characterization of genes for functional identification and analysis of a gene's dependency among other genes. Gene co-expression databases have been developed for other species, but gene co-expression information for plants is currently limited. DESCRIPTION: We constructed PLANEX as a list of co-expressed genes and functional annotations for Arabidopsis thaliana, Glycine max, Hordeum vulgare, Oryza sativa, Solanum lycopersicum, Triticum aestivum, Vitis vinifera and Zea mays. PLANEX reports Pearson's correlation coefficients (PCCs; r-values) that distribute from a gene of interest for a given microarray platform set corresponding to a particular organism. To support PCCs, PLANEX performs an enrichment test of Gene Ontology terms and Cohen's Kappa value to compare functional similarity for all genes in the co-expression database. PLANEX draws a cluster network with co-expressed genes, which is estimated using the k-mean method. To construct PLANEX, a variety of datasets were interpreted by the IBM supercomputer Advanced Interactive eXecutive (AIX) in a supercomputing center. CONCLUSION: PLANEX provides a correlation database, a cluster network and an interpretation of enrichment test results for eight plant species. A typical co-expressed gene generates lists of co-expression data that contain hundreds of genes of interest for enrichment analysis. Also, co-expressed genes can be identified and cataloged in terms of comparative genomics by using the 'Co-expression gene compare' feature. This type of analysis will help interpret experimental data and determine whether there is a common term among genes of interest.


Assuntos
Bases de Dados de Ácidos Nucleicos , Genes de Plantas , Proteínas de Plantas/genética , Plantas/genética , Internet
14.
Gene ; 515(1): 155-8, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23201897

RESUMO

BACKGROUND/AIMS: The aim of the present study is to probe the potential association between previously-reported GARP2 mutations and retinitis pigmentosa (RP) using Scottish RP patients and controls. METHODS: Exons 4, 5 and 8 in DNA from blood or buccal samples (130 autosomal recessive and simplex RP patients, 31 controls) were amplified and analysed for single-strand conformational polymorphism by capillary electrophoresis (CE-SSCP) and confirmed by sequencing. RESULTS: The p.Arg86Gln mutation in exon 4 was found in just one patient (out of 130), and in 10 of the 31 unaffected subjects. All of these occurrences were in people of West African origin (patient and controls). Two polymorphisms in exon 5, p.His100Arg and p.Gly109Gly, and a c.534+20A>G change in the intronic region flanking the 3' end of exon 8 were also found not to be associated with RP. CONCLUSIONS: The Scottish population examined here had no mutations in the GARP2 exons surveyed that could be associated with RP. The p.Arg86Gln mutation actually appears to be a polymorphism common in ethnic West Africans and not associated with RP. This change may provide a useful marker for West African ancestry.


Assuntos
Substituição de Aminoácidos , População Negra/genética , Polimorfismo de Nucleotídeo Único , África Ocidental , Sequência de Aminoácidos , Sequência de Bases , Estudos de Casos e Controles , Canais de Cátion Regulados por Nucleotídeos Cíclicos , Éxons , Humanos , Dados de Sequência Molecular , Retinose Pigmentar/genética , Escócia , Alinhamento de Sequência , População Branca/genética
15.
Mol Vis ; 17: 3423-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22219638

RESUMO

PURPOSE: The aim of this study was to identify glucocorticoid induced cataracts (GIC)-specific modified water insoluble-urea soluble (WI-US) crystallins and related changes after rat lens were exposed to dexamethasone (Dex). METHODS: We separated WI-US lens proteins by two-dimensional electrophoresis (2-DE). The crystallins were then analyzed with matrix assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-MS/MS). Protein levels and morphological changes of αA- and αB-crystallins were also determined. Electronic microscope of lens and native-page analysis of crystallins were further determined. RESULTS: Measured masses, isoelectric points (pIs), and amino acid sequences of all detected crystallins matched previously-reported data. Analysis by 2-DE indicated that αA- and αB-crystallin increased when the lens was viewed under 1 µM and 10 µM Dex, which was identical with the results of western-blot, immuno histochemistry or fluorescence; ßB2- and ßA3-crystallin increased when lens was viewed under 1 µM Dex and 100 µM Dex. ßA1-, ßA4-, and ßB1-crystallins decreased under 0.1-100 µM Dex. Electronic microscope figures showed the condition of the lens center gradually worsened and cracked between fiber cells that became larger under 1-100 µM Dex. Moreover, αA-crystallins were associated with increased phosphorylation (PI decreased).The newly protein spots: ßA2-, ßA3-, ßB1-, and γs-crystallin appeared under 0.1-100 µM Dex. Native-page showed α-crystallin increased when the lens was exposed to 1 µM Dex; however, ß-crystallin did not decrease under 0.1-100 µM Dex. The percentage of α-crystallin gradually decreased, however ß-crystallin gradually increased, perhaps because the emergence of newly appeared ß-crystallin under Dex. CONCLUSIONS: Our results showed multiple WI-US crystallins may be more vulnerable to glucocorticoid stress because of diminished important roles, which will in turn provide a mechanism for GIC from a proteomics perspective.


Assuntos
Catarata/metabolismo , Cristalinas/análise , Dexametasona/efeitos adversos , Cristalino/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Catarata/induzido quimicamente , Catarata/patologia , Cristalinas/classificação , Relação Dose-Resposta a Droga , Eletroforese em Gel Bidimensional , Glucocorticoides/efeitos adversos , Cristalino/metabolismo , Cristalino/patologia , Masculino , Dados de Sequência Molecular , Peso Molecular , Proteômica , Ratos , Ratos Sprague-Dawley , Solubilidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Ureia , Água
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