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1.
Comput Biol Med ; 167: 107596, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37890423

RESUMO

Organ segmentation in abdominal or thoracic computed tomography (CT) images plays a crucial role in medical diagnosis as it enables doctors to locate and evaluate organ abnormalities quickly, thereby guiding surgical planning, and aiding treatment decision-making. This paper proposes a novel and efficient medical image segmentation method called SUnet for multi-organ segmentation in the abdomen and thorax. SUnet is a fully attention-based neural network. Firstly, an efficient spatial reduction attention (ESRA) module is introduced not only to extract image features better, but also to reduce overall model parameters, and to alleviate overfitting. Secondly, SUnet's multiple attention-based feature fusion module enables effective cross-scale feature integration. Additionally, an enhanced attention gate (EAG) module is considered by using grouped convolution and residual connections, providing richer semantic features. We evaluate the performance of the proposed model on synapse multiple organ segmentation dataset and automated cardiac diagnostic challenge dataset. SUnet achieves an average Dice of 84.29% and 92.25% on these two datasets, respectively, outperforming other models of similar complexity and size, and achieving state-of-the-art results.


Assuntos
Coração , Redes Neurais de Computação , Semântica , Tórax , Tomografia Computadorizada por Raios X , Processamento de Imagem Assistida por Computador
2.
BMC Bioinformatics ; 24(1): 188, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158823

RESUMO

BACKGROUND: The limited knowledge of miRNA-lncRNA interactions is considered as an obstruction of revealing the regulatory mechanism. Accumulating evidence on Human diseases indicates that the modulation of gene expression has a great relationship with the interactions between miRNAs and lncRNAs. However, such interaction validation via crosslinking-immunoprecipitation and high-throughput sequencing (CLIP-seq) experiments that inevitably costs too much money and time but with unsatisfactory results. Therefore, more and more computational prediction tools have been developed to offer many reliable candidates for a better design of further bio-experiments. METHODS: In this work, we proposed a novel link prediction model based on Gaussian kernel-based method and linear optimization algorithm for inferring miRNA-lncRNA interactions (GKLOMLI). Given an observed miRNA-lncRNA interaction network, the Gaussian kernel-based method was employed to output two similarity matrixes of miRNAs and lncRNAs. Based on the integrated matrix combined with similarity matrixes and the observed interaction network, a linear optimization-based link prediction model was trained for inferring miRNA-lncRNA interactions. RESULTS: To evaluate the performance of our proposed method, k-fold cross-validation (CV) and leave-one-out CV were implemented, in which each CV experiment was carried out 100 times on a training set generated randomly. The high area under the curves (AUCs) at 0.8623 ± 0.0027 (2-fold CV), 0.9053 ± 0.0017 (5-fold CV), 0.9151 ± 0.0013 (10-fold CV), and 0.9236 (LOO-CV), illustrated the precision and reliability of our proposed method. CONCLUSION: GKLOMLI with high performance is anticipated to be used to reveal underlying interactions between miRNA and their target lncRNAs, and deciphers the potential mechanisms of the complex diseases.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , Reprodutibilidade dos Testes , Projetos de Pesquisa , Algoritmos , MicroRNAs/genética
3.
IEEE/ACM Trans Comput Biol Bioinform ; 20(5): 2690-2699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36374878

RESUMO

Transcription factors (TFs) play a part in gene expression. TFs can form complex gene expression regulation system by combining with DNA. Thereby, identifying the binding regions has become an indispensable step for understanding the regulatory mechanism of gene expression. Due to the great achievements of applying deep learning (DL) to computer vision and language processing in recent years, many scholars are inspired to use these methods to predict TF binding sites (TFBSs), achieving extraordinary results. However, these methods mainly focus on whether DNA sequences include TFBSs. In this paper, we propose a fully convolutional network (FCN) coupled with refinement residual block (RRB) and global average pooling layer (GAPL), namely FCNARRB. Our model could classify binding sequences at nucleotide level by outputting dense label for input data. Experimental results on human ChIP-seq datasets show that the RRB and GAPL structures are very useful for improving model performance. Adding GAPL improves the performance by 9.32% and 7.61% in terms of IoU (Intersection of Union) and PRAUC (Area Under Curve of Precision and Recall), and adding RRB improves the performance by 7.40% and 4.64%, respectively. In addition, we find that conservation information can help locate TFBSs.

4.
IEEE/ACM Trans Comput Biol Bioinform ; 20(5): 2629-2638, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35925844

RESUMO

Growing studies have shown that miRNAs are inextricably linked with many human diseases, and a great deal of effort has been spent on identifying their potential associations. Compared with traditional experimental methods, computational approaches have achieved promising results. In this article, we propose a graph representation learning method to predict miRNA-disease associations. Specifically, we first integrate the verified miRNA-disease associations with the similarity information of miRNA and disease to construct a miRNA-disease heterogeneous graph. Then, we apply a graph attention network to aggregate the neighbor information of nodes in each layer, and then feed the representation of the hidden layer into the structure-aware jumping knowledge network to obtain the global features of nodes. The output features of miRNAs and diseases are then concatenated and fed into a fully connected layer to score the potential associations. Through five-fold cross-validation, the average AUC, accuracy and precision values of our model are 93.30%, 85.18% and 88.90%, respectively. In addition, for three case studies of the esophageal tumor, lymphoma and prostate tumor, 46, 45 and 45 of the top 50 miRNAs predicted by our model were confirmed by relevant databases. Overall, our method could provide a reliable alternative for miRNA-disease association prediction.

5.
Artigo em Inglês | MEDLINE | ID: mdl-30137012

RESUMO

Underlying a cancer phenotype is a specific gene regulatory network that represents the complex regulatory relationships between genes. However, it remains a challenge to find cancer-related gene regulatory network because of insufficient sample sizes and complex regulatory mechanisms in which gene is influenced by not only other genes but also other biological factors. With the development of high-throughput technologies and the unprecedented wealth of multi-omics data give us a new opportunity to design machine learning method to investigate underlying gene regulatory network. In this paper, we propose an approach, which use biweight midcorrelation to measure the correlation between factors and make use of nonconvex penalty based sparse regression for gene regulatory network inference (BMNPGRN). BMNCGRN incorporates multi-omics data (including DNA methylation and copy number variation) and their interactions in gene regulatory network model. The experimental results on synthetic datasets show that BMNPGRN outperforms popular and state-of-the-art methods (including DCGRN, ARACNE and CLR) under false positive control. Furthermore, we applied BMNPGRN on breast cancer (BRCA) data from The Cancer Genome Atlas database and provided gene regulatory network.

6.
PLoS One ; 13(6): e0198922, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29953448

RESUMO

Both in DNA and protein contexts, an important method for modelling motifs is to utilize position weight matrix (PWM) in biological sequences. With the development of genome sequencing technology, the quantity of the sequence data is increasing explosively, so the faster searching algorithms which have the ability to meet the increasingly need are desired to develop. In this paper, we proposed a method for speeding up the searching process of candidate transcription factor binding sites (TFBS), and the users can be allowed to specify p threshold to get the desired trade-off between speed and sensitivity for a particular sequence analysis. Moreover, the proposed method can also be generalized to large-scale annotation and sequence projects.


Assuntos
Elementos de Resposta , Análise de Sequência de DNA/métodos , Software , Fatores de Transcrição/genética
7.
IEEE/ACM Trans Comput Biol Bioinform ; 15(5): 1453-1460, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28961121

RESUMO

Post translational modification plays a significiant role in the biological processing. The potential post translational modification is composed of the center sites and the adjacent amino acid residues which are fundamental protein sequence residues. It can be helpful to perform their biological functions and contribute to understanding the molecular mechanisms that are the foundations of protein design and drug design. The existing algorithms of predicting modified sites often have some shortcomings, such as lower stability and accuracy. In this paper, a combination of physical, chemical, statistical, and biological properties of a protein have been ulitized as the features, and a novel framework is proposed to predict a protein's post translational modification sites. The multi-layer neural network and support vector machine are invoked to predict the potential modified sites with the selected features that include the compositions of amino acid residues, the E-H description of protein segments, and several properties from the AAIndex database. Being aware of the possible redundant information, the feature selection is proposed in the propocessing step in this research. The experimental results show that the proposed method has the ability to improve the accuracy in this classification issue.


Assuntos
Biologia Computacional/métodos , Processamento de Proteína Pós-Traducional/genética , Proteínas/química , Proteínas/genética , Análise de Sequência de Proteína/métodos , Algoritmos , Sequência de Aminoácidos , Animais , Humanos , Camundongos , Modelos Moleculares , Saccharomyces cerevisiae/genética , Máquina de Vetores de Suporte
8.
Appl Plant Sci ; 5(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28090413

RESUMO

PREMISE OF THE STUDY: Microsatellite markers were developed for Garcinia paucinervis (Clusiaceae), an endangered and endemic tree species of karst habitats, to analyze its genetic diversity and genetic structure. METHODS AND RESULTS: Using shotgun sequencing on an Illumina MiSeq platform, a total of 22 microsatellite primer sets were characterized, of which 17 were identified as polymorphic. For these polymorphic loci, the total number of alleles per locus ranged from two to 12 across 54 individuals from three populations. The observed and expected heterozygosities ranged from 0.000 to 1.000 and from 0.000 to 0.850, respectively. No pair of loci showed significant linkage disequilibrium. Three loci in one population deviated significantly from Hardy-Weinberg equilibrium (P < 0.05). Seven loci (JSL3, JSL5, JSL22, JSL29, JSL32, JSL39, and JSL43) were successfully amplified in G. bracteata. CONCLUSIONS: These markers will be useful in studies on genetic diversity and population structure of G. paucinervis.

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