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1.
Article in English | MEDLINE | ID: mdl-35594221

ABSTRACT

Finding the causal relation between a gene and a disease using experimental approaches is a time-consuming and expensive task. However, computational approaches are cost-efficient methods for identifying candidate genes. This article proposes a new heterogeneous biological network embedding approach, named NetEM, to identify disease-associated genes. To evaluate NetEM, we examine six complex diseases, including peroxisomal disorders, sarcoma, grave's disease, lysosomal storage diseases, blood coagulation disorders, and cardiomyopathy hypertrophic. Our experiments indicate that NetEM outperforms three well-known state-of-the-art algorithms: Cardigan, DIAMOnD and GeneWanderer, in identifying disease genes. We examine TCGA data of Invasive Lobular Breast Cancer and CPTAC data of human glioblastoma as other case studies to evaluate NetEM using real data. This evaluation also indicates the validity of the method. The source codes of NetEM and data are available in the supplementary of this article.


Subject(s)
Glioblastoma , Sarcoma , Humans , Algorithms , Computational Biology
2.
J Theor Biol ; 556: 111311, 2023 01 07.
Article in English | MEDLINE | ID: mdl-36257351

ABSTRACT

Modeling of the biological neurons is a way to understand the architecture of neural networks of the brain. A complex brain network includes the synchronization between some groups of neurons. The dynamic behavior of interactions between groups of slave-master neurons in the neocortical network is unpredictable and challenging. The purpose of synchronizing a neural interaction is to reduce the synchronization error between the chaotic slave-master neurons. This paper uses a proportional-integral-derivative (PID) controller to synchronize master-slave neurons in the fractional-order of the neocortical network model based on dendritic spike frequency adaptation (DSFA) uncertainties and unknown disturbance effects. The purpose of this article is in two parts: First, we implemented the effect of previous states of the neuron conditions by fractional-order of the differential equations in the neocortical network model. Second, by synchronizing the FO neocortical master-slave model by PID controller, we investigated the connection strength of the complex network in chaotic point of view. The optimized PID coefficients and fractional-order were calculated using root mean square error (RMSE) criteria to control the membrane voltage synchronization. The chaotic behavior of the system was evaluated by numerical techniques such as attractor analysis and time series diagrams. The optimal RMSE value for master-slave neurons occurred at fractional-orders 0.89. It is shown that the synchronization of master-slave neurons improves over time, and eventually they are fully synchronized while the controller error is reduced.


Subject(s)
Neocortex , Neural Networks, Computer , Neurons/physiology , Time Factors
3.
J Theor Biol ; 528: 110837, 2021 11 07.
Article in English | MEDLINE | ID: mdl-34273361

ABSTRACT

Studying the dynamical behaviors of neuronal models may help in better understanding of real nervous system. In addition, it can help researchers to understand some specific phenomena in neuronal system. The thalamocortical network is made of neurons in the thalamus and cortex. In it, the memory function is consolidated in sleep by creating up and down state oscillations (1 Hz) and fast (13-17 Hz) - slow (8-12 Hz) spindles. Recently, a nonlinear biological model for up-down oscillations and fast-slow spindles of the thalamocortical network has been proposed. In this research, the power spectral for the fast-slow spindle of the model is extracted. Dynamical properties of the model, such as the bifurcation diagrams, and attractors are investigated. The results show that the variation of the synaptic power between the excitatory neurons of the cortex and the reticular neurons in the thalamus changes the spindles' activity. According to previous experimental findings, it is an essential rule for consolidating the memory function during sleep. It is also pointed out that when the fast-slow spindles of the brain increase, the dynamics of the thalamocortical system tend to chaos.


Subject(s)
Nonlinear Dynamics , Sleep , Cerebral Cortex , Electroencephalography , Neurons , Thalamus
4.
Brain Behav ; 11(5): e02101, 2021 05.
Article in English | MEDLINE | ID: mdl-33784022

ABSTRACT

PURPOSE: Resting-state functional magnetic resonance imaging (Rs-fMRI) can be used to investigate the alteration of resting-state brain networks (RSNs) in patients with Parkinson's disease (PD) when compared with healthy controls (HCs). The aim of this study was to identify the differences between individual RSNs and reveal the most important discriminatory characteristic of RSNs between the HCs and PDs. METHODS: This study used Rs-fMRI data of 23 patients with PD and 18 HCs. Group independent component analysis (ICA) was performed, and 23 components were extracted by spatially overlapping the components with a template RSN. The extracted components were used in the following three methods to compare RSNs of PD patients and HCs: (1) a subject-specific score based on group RSNs and a dual-regression approach (namely RSN scores); (2) voxel-wise comparison of the RSNs in the PD patient and HC groups using a nonparametric permutation test; and (3) a hierarchical clustering analysis of RSNs in the PD patient and HC groups. RESULTS: The results of RSN scores showed a significant decrease in connectivity in seven ICs in patients with PD compared with HCs, and this decrease was particularly striking on the lateral and medial posterior occipital cortices. The results of hierarchical clustering of the RSNs revealed that the cluster of the default mode network breaks down into the three other clusters in PD patients. CONCLUSION: We found various characteristics of the alteration of the RSNs in PD patients compared with HCs. Our results suggest that different characteristics of RSNs provide insights into the biological mechanism of PD.


Subject(s)
Parkinson Disease , Brain/diagnostic imaging , Brain Mapping , Humans , Magnetic Resonance Imaging , Nerve Net/diagnostic imaging , Parkinson Disease/diagnostic imaging
5.
J Gerontol Nurs ; 46(6): 25-33, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32453437

ABSTRACT

Caregivers of individuals with heart failure are at high risk for diminished quality of life because of the energy involved in providing necessary care. Caring for someone with chronic heart failure can affect caregivers' physical, psychological, and social health, collectively referred to as the burden of care, and may also affect family functioning. The current cross-sectional study aimed to investigate the relationship between caregiver burden and family functioning in caregivers of older adults with heart failure in southeastern Iran using the Zarit Burden Inventory and the Family Assessment Device based on the McMaster Model of Family Functioning. The Pearson correlation coefficient, independent t test, and analysis of variance were used to determine relationships among variables. Results showed a significant correlation between burden of care and total score of family functioning. Therefore, it is necessary to take measures to reduce burden of care for caregivers through education and support programs and to improve their family functioning and quality of life. [Journal of Gerontological Nursing, 46(6), 25-33.].


Subject(s)
Caregiver Burden/psychology , Caregivers/psychology , Family Relations/psychology , Heart Failure/nursing , Adaptation, Psychological , Adolescent , Adult , Aged , Aged, 80 and over , Chronic Disease , Cost of Illness , Cross-Sectional Studies , Female , Health Status , Humans , Iran , Male , Middle Aged , Quality of Life/psychology , Social Support , Surveys and Questionnaires , Young Adult
6.
J Med Signals Sens ; 3(2): 69-78, 2013 Apr.
Article in English | MEDLINE | ID: mdl-24098860

ABSTRACT

Parkinson's disease (PD) is a progressive neurological disorder characterized by tremor, rigidity, and slowness of movements. Particular changes related to various pathological attacks in PD could result in causal interactions of the brain network from resting state functional magnetic resonance imaging (rs-fMRI) data. In this paper, we aimed to disclose the network structure of the directed influences over the brain using multivariate Granger causality analysis and graph theory in patients with PD as compared with control group. rs-fMRI at rest from 10 PD patients and 10 controls were analyzed. Topological properties of the networks showed that information flow in PD is smaller than that in healthy individuals. We found that there is a balanced local network in healthy control group, including positive pair-wise cross connections between caudate and cerebellum and reciprocal connections between motor cortex and caudate in the left and right hemispheres. The results showed that this local network is disrupted in PD due to disturbance of the interactions in the motor networks. These findings suggested alteration of the functional organization of the brain in the resting state that affects the information transmission from and to other brain regions related to both primary dysfunctions and higher-level cognition impairments in PD. Furthermore, we showed that regions with high degree values could be detected as betweenness centrality nodes. Our results demonstrate that properties of small-world connectivity could also recognize and quantify the characteristics of directed influence brain networks in PD.

7.
PLoS One ; 8(9): e72366, 2013.
Article in English | MEDLINE | ID: mdl-24039752

ABSTRACT

Graph clustering algorithms are widely used in the analysis of biological networks. Extracting functional modules in protein-protein interaction (PPI) networks is one such use. Most clustering algorithms whose focuses are on finding functional modules try either to find a clique like sub networks or to grow clusters starting from vertices with high degrees as seeds. These algorithms do not make any difference between a biological network and any other networks. In the current research, we present a new procedure to find functional modules in PPI networks. Our main idea is to model a biological concept and to use this concept for finding good functional modules in PPI networks. In order to evaluate the quality of the obtained clusters, we compared the results of our algorithm with those of some other widely used clustering algorithms on three high throughput PPI networks from Sacchromyces Cerevisiae, Homo sapiens and Caenorhabditis elegans as well as on some tissue specific networks. Gene Ontology (GO) analyses were used to compare the results of different algorithms. Each algorithm's result was then compared with GO-term derived functional modules. We also analyzed the effect of using tissue specific networks on the quality of the obtained clusters. The experimental results indicate that the new algorithm outperforms most of the others, and this improvement is more significant when tissue specific networks are used.


Subject(s)
Protein Interaction Mapping/methods , Protein Interaction Maps , Algorithms , Caenorhabditis elegans Proteins/physiology , Cluster Analysis , Computational Biology , Computer Simulation , Gene Ontology , Humans , Models, Biological , Saccharomyces cerevisiae Proteins/physiology
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