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  1. Article: Evaluation of network-guided random forest for disease gene discovery.

    Hu, Jianchang / Szymczak, Silke

    BioData mining

    2024  Volume 17, Issue 1, Page(s) 10

    Abstract: Background: Gene network information is believed to be beneficial for disease module and pathway identification, but has not been explicitly utilized in the standard random forest (RF) algorithm for gene expression data analysis. We investigate the ... ...

    Abstract Background: Gene network information is believed to be beneficial for disease module and pathway identification, but has not been explicitly utilized in the standard random forest (RF) algorithm for gene expression data analysis. We investigate the performance of a network-guided RF where the network information is summarized into a sampling probability of predictor variables which is further used in the construction of the RF.
    Results: Our simulation results suggest that network-guided RF does not provide better disease prediction than the standard RF. In terms of disease gene discovery, if disease genes form module(s), network-guided RF identifies them more accurately. In addition, when disease status is independent from genes in the given network, spurious gene selection results can occur when using network information, especially on hub genes. Our empirical analysis on two balanced microarray and RNA-Seq breast cancer datasets from The Cancer Genome Atlas (TCGA) for classification of progesterone receptor (PR) status also demonstrates that network-guided RF can identify genes from PGR-related pathways, which leads to a better connected module of identified genes.
    Conclusions: Gene networks can provide additional information to aid the gene expression analysis for disease module and pathway identification. But they need to be used with caution and validation on the results need to be carried out to guard against spurious gene selection. More robust approaches to incorporate such information into RF construction also warrant further study.
    Language English
    Publishing date 2024-04-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 2438773-3
    ISSN 1756-0381
    ISSN 1756-0381
    DOI 10.1186/s13040-024-00361-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: A review on longitudinal data analysis with random forest.

    Hu, Jianchang / Szymczak, Silke

    Briefings in bioinformatics

    2023  Volume 24, Issue 2

    Abstract: In longitudinal studies variables are measured repeatedly over time, leading to clustered and correlated observations. If the goal of the study is to develop prediction models, machine learning approaches such as the powerful random forest (RF) are often ...

    Abstract In longitudinal studies variables are measured repeatedly over time, leading to clustered and correlated observations. If the goal of the study is to develop prediction models, machine learning approaches such as the powerful random forest (RF) are often promising alternatives to standard statistical methods, especially in the context of high-dimensional data. In this paper, we review extensions of the standard RF method for the purpose of longitudinal data analysis. Extension methods are categorized according to the data structures for which they are designed. We consider both univariate and multivariate response longitudinal data and further categorize the repeated measurements according to whether the time effect is relevant. Even though most extensions are proposed for low-dimensional data, some can be applied to high-dimensional data. Information of available software implementations of the reviewed extensions is also given. We conclude with discussions on the limitations of our review and some future research directions.
    MeSH term(s) Random Forest ; Longitudinal Studies ; Software ; Data Analysis
    Language English
    Publishing date 2023-01-11
    Publishing country England
    Document type Review ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2068142-2
    ISSN 1477-4054 ; 1467-5463
    ISSN (online) 1477-4054
    ISSN 1467-5463
    DOI 10.1093/bib/bbad002
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Functional evaluation of cyclosporine metabolism by CYP3A4 variants and potential drug interactions.

    Kong, Qihui / Gao, Nanyong / Wang, Yahui / Hu, Guoxin / Qian, Jianchang / Chen, Bingbing

    Frontiers in pharmacology

    2023  Volume 13, Page(s) 1044817

    Abstract: The aim of this study is to investigate the effects of CYP3A4 genetic polymorphisms on the metabolism of cyclosporine (CsA) ...

    Abstract The aim of this study is to investigate the effects of CYP3A4 genetic polymorphisms on the metabolism of cyclosporine (CsA)
    Language English
    Publishing date 2023-01-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2587355-6
    ISSN 1663-9812
    ISSN 1663-9812
    DOI 10.3389/fphar.2022.1044817
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Study on genotype and phenotype of novel CYP2D6 variants using pharmacokinetic and pharmacodynamic models with metoprolol as a substrate drug.

    Qian, Jianchang / Xu, Tao / Pan, Peipei / Sun, Wei / Hu, Guoxin / Cai, Jianping

    The pharmacogenomics journal

    2024  Volume 24, Issue 3, Page(s) 13

    Abstract: To investigate the pharmacokinetic and pharmacodynamic profiles of volunteers carrying CYP2D6 genotypes with unknow metabolic phenotypes, a total of 22 volunteers were recruited based on the sequencing results. Peripheral blood and urine samples were ... ...

    Abstract To investigate the pharmacokinetic and pharmacodynamic profiles of volunteers carrying CYP2D6 genotypes with unknow metabolic phenotypes, a total of 22 volunteers were recruited based on the sequencing results. Peripheral blood and urine samples were collected at specific time points after oral administration of metoprolol. A validated high-performance liquid chromatography (HPLC) method was used to determine the concentrations of metoprolol and α-hydroxymetoprolol. Blood pressure and electrocardiogram were also monitored. The results showed that the main pharmacokinetic parameters of metoprolol in CYP2D6*1/*34 carriers are similar to those in CYP2D6*1/*1 carriers. However, in individuals carrying the CYP2D6*10/*87, CYP2D6*10/*95, and CYP2D6*97/*97 genotypes, the area under the curve (AUC) and half-life (t1/2) of metoprolol increased by 2-3 times compared to wild type. The urinary metabolic ratio of metoprolol in these genotypes is consistent with the trends observed in plasma samples. Therefore, CYP2D6*1/*34 can be considered as normal metabolizers, while CYP2D6*10/*87, CYP2D6*10/*95, and CYP2D6*97/*97 are intermediate metabolizers. Although the blood concentration of metoprolol has been found to correlate with CYP2D6 genotype, its blood pressure-lowering effect reaches maximum effectiveness at a reduction of 25 mmHg. Furthermore, P-Q interval prolongation and heart rate reduction are not positively correlated with metoprolol blood exposure. Based on the pharmacokinetic-pharmacodynamic model, this study clarified the properties of metoprolol in subjects with novel CYP2D6 genotypes and provided important fundamental data for the translational medicine of this substrate drug.
    MeSH term(s) Humans ; Metoprolol/pharmacokinetics ; Metoprolol/urine ; Adrenergic beta-Antagonists ; Cytochrome P-450 CYP2D6/genetics ; Cytochrome P-450 CYP2D6/metabolism ; Pharmaceutical Preparations ; Genotype ; Phenotype
    Chemical Substances Metoprolol (GEB06NHM23) ; Adrenergic beta-Antagonists ; Cytochrome P-450 CYP2D6 (EC 1.14.14.1) ; Pharmaceutical Preparations
    Language English
    Publishing date 2024-04-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2106831-8
    ISSN 1473-1150 ; 1470-269X
    ISSN (online) 1473-1150
    ISSN 1470-269X
    DOI 10.1038/s41397-024-00332-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Rapid and accurate identification of marine bacteria spores at a single-cell resolution by laser tweezers Raman spectroscopy and deep learning.

    Hu, Jianchang / He, Lin / Wang, Guiwen / Liu, Liwei / Wang, Yiping / Song, Jun / Qu, Junle / Peng, Xiao / Yuan, Yufeng

    Journal of biophotonics

    2024  , Page(s) e202300510

    Abstract: Marine bacteria have been considered as important participants in revealing various carbon/sulfur/nitrogen cycles of marine ecosystem. Thus, how to accurately identify rare marine bacteria without a culture process is significant and valuable. In this ... ...

    Abstract Marine bacteria have been considered as important participants in revealing various carbon/sulfur/nitrogen cycles of marine ecosystem. Thus, how to accurately identify rare marine bacteria without a culture process is significant and valuable. In this work, we constructed a single-cell Raman spectra dataset from five living bacteria spores and utilized convolutional neural network to rapidly, accurately, nondestructively identify bacteria spores. The optimal CNN architecture can provide a prediction accuracy of five bacteria spore as high as 94.93% ± 1.78%. To evaluate the classification weight of extracted spectra features, we proposed a novel algorithm by occluding fingerprint Raman bands. Based on the relative classification weight arranged from large to small, four Raman bands located at 1518, 1397, 1666, and 1017 cm
    Language English
    Publishing date 2024-02-01
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2390063-5
    ISSN 1864-0648 ; 1864-063X
    ISSN (online) 1864-0648
    ISSN 1864-063X
    DOI 10.1002/jbio.202300510
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Book ; Online: A review on longitudinal data analysis with random forest in precision medicine

    Hu, Jianchang / Szymczak, Silke

    2022  

    Abstract: Precision medicine provides customized treatments to patients based on their characteristics and is a promising approach to improving treatment efficiency. Large scale omics data are useful for patient characterization, but often their measurements ... ...

    Abstract Precision medicine provides customized treatments to patients based on their characteristics and is a promising approach to improving treatment efficiency. Large scale omics data are useful for patient characterization, but often their measurements change over time, leading to longitudinal data. Random forest is one of the state-of-the-art machine learning methods for building prediction models, and can play a crucial role in precision medicine. In this paper, we review extensions of the standard random forest method for the purpose of longitudinal data analysis. Extension methods are categorized according to the data structures for which they are designed. We consider both univariate and multivariate responses and further categorize the repeated measurements according to whether the time effect is relevant. Information of available software implementations of the reviewed extensions is also given. We conclude with discussions on the limitations of our review and some future research directions.

    Comment: 27 pages, 2 figures, 3 tables
    Keywords Statistics - Machine Learning ; Computer Science - Machine Learning
    Subject code 006
    Publishing date 2022-08-08
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article: Helicobacter pylori

    Liu, Zichuan / Li, Jianchang / Hu, Xiaoshan / Xu, Houwei

    Journal of gastrointestinal oncology

    2021  Volume 12, Issue 3, Page(s) 1058–1073

    Abstract: Background: Helicobacter pylori: Methods: The GSE6143 dataset was used to identify differentially expressed genes (DEGs) with limma R package, and enrichment analysis was done using the Metascape web-based portal. The protein-protein interaction ... ...

    Abstract Background: Helicobacter pylori
    Methods: The GSE6143 dataset was used to identify differentially expressed genes (DEGs) with limma R package, and enrichment analysis was done using the Metascape web-based portal. The protein-protein interaction analysis was done using Search Tool for the Retrieval of Interacting Genes/Proteins. Gastric adenocarcinoma AGS and BGC-823 cells were treated with
    Results: DEGs in gastric mucosa with or without
    Conclusions: H. pylori
    Language English
    Publishing date 2021-07-18
    Publishing country China
    Document type Journal Article
    ZDB-ID 2594644-4
    ISSN 2219-679X ; 2078-6891
    ISSN (online) 2219-679X
    ISSN 2078-6891
    DOI 10.21037/jgo-21-305
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Characterization of T-cell receptors and immunoglobulin heavy chains loci and identification of T/B cell clusters in teleost.

    Chen, Weijie / Hu, Jing / Huang, Jianchang / Liu, Qin / Wang, Qiyao / Zhang, Yuanxing / Yang, Dahai

    Fish & shellfish immunology

    2023  Volume 136, Page(s) 108746

    Abstract: Bacterial disease is one of the important factors leading to economic losses in the turbot (Scophthalmus maximus) cultivation industry. T lymphocytes are major components of cellular immunity, whereas B lymphocytes produce immunoglobulins (Ig) that are ... ...

    Abstract Bacterial disease is one of the important factors leading to economic losses in the turbot (Scophthalmus maximus) cultivation industry. T lymphocytes are major components of cellular immunity, whereas B lymphocytes produce immunoglobulins (Ig) that are key elements of humoral immune responses against infection. However, the genomic organization of genes encoding T-cell receptors (TCR) and immunoglobulin heavy chains (IgHs) in turbot remains largely unknown. In this study, abundant full-length transcripts of TCRs and IgHs were sequenced by Isoform-sequencing (Iso-seq), and we investigated and annotated the V, D, J and C gene loci of TCRα, TCRβ, IgT, IgM and IgD in turbot. Furthermore, through single-cell RNA sequencing (scRNA-seq) of blood leukocytes, we confirmed that these identified TCRs and IgHs were highly expressed in T/B cell clusters, respectively. Meanwhile, we also identified the IgM
    MeSH term(s) Animals ; T-Lymphocytes ; Receptors, Antigen, T-Cell/genetics ; Immunoglobulin Heavy Chains/genetics ; Biological Evolution ; Immunoglobulin M/genetics ; Immunoglobulin M/metabolism
    Chemical Substances Receptors, Antigen, T-Cell ; Immunoglobulin Heavy Chains ; Immunoglobulin M
    Language English
    Publishing date 2023-04-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 1067738-0
    ISSN 1095-9947 ; 1050-4648
    ISSN (online) 1095-9947
    ISSN 1050-4648
    DOI 10.1016/j.fsi.2023.108746
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Super-taxon in human microbiome are identified to be associated with colorectal cancer

    Wei Dai / Cai Li / Ting Li / Jianchang Hu / Heping Zhang

    BMC Bioinformatics, Vol 23, Iss 1, Pp 1-

    2022  Volume 18

    Abstract: Abstract Background Microbial communities in the human body, also known as human microbiota, impact human health, such as colorectal cancer (CRC). However, the different roles that microbial communities play in healthy and disease hosts remain largely ... ...

    Abstract Abstract Background Microbial communities in the human body, also known as human microbiota, impact human health, such as colorectal cancer (CRC). However, the different roles that microbial communities play in healthy and disease hosts remain largely unknown. The microbial communities are typically recorded through the taxa counts of operational taxonomic units (OTUs). The sparsity and high correlations among OTUs pose major challenges for understanding the microbiota-disease relation. Furthermore, the taxa data are structured in the sense that OTUs are related evolutionarily by a hierarchical structure. Results In this study, we borrow the idea of super-variant from statistical genetics, and propose a new concept called super-taxon to exploit hierarchical structure of taxa for microbiome studies, which is essentially a combination of taxonomic units. Specifically, we model a genus which consists of a set of OTUs at low hierarchy and is designed to reflect both marginal and joint effects of OTUs associated with the risk of CRC to address these issues. We first demonstrate the power of super-taxon in detecting highly correlated OTUs. Then, we identify CRC-associated OTUs in two publicly available datasets via a discovery-validation procedure. Specifically, four species of two genera are found to be associated with CRC: Parvimonas micra, Parvimonas sp., Peptostreptococcus stomatis, and Peptostreptococcus anaerobius. More importantly, for the first time, we report the joint effect of Parvimonas micra and Parvimonas sp. (p = 0.0084) as well as that of Peptostrepto-coccus stomatis and Peptostreptococcus anaerobius (p = 8.21e-06) on CRC. The proposed approach provides a novel and useful tool for identifying disease-related microbes by taking the hierarchical structure of taxa into account and further sheds new lights on their potential joint effects as a community in disease development. Conclusions Our work shows that proposed approaches are effective to study the microbiota-disease relation taking into account for ...
    Keywords Colorectal cancer ; Microbiota-disease association studies ; Microbiome joint effects ; Super-Taxon ; Computer applications to medicine. Medical informatics ; R858-859.7 ; Biology (General) ; QH301-705.5
    Language English
    Publishing date 2022-06-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Super-taxon in human microbiome are identified to be associated with colorectal cancer.

    Dai, Wei / Li, Cai / Li, Ting / Hu, Jianchang / Zhang, Heping

    BMC bioinformatics

    2022  Volume 23, Issue 1, Page(s) 243

    Abstract: Background: Microbial communities in the human body, also known as human microbiota, impact human health, such as colorectal cancer (CRC). However, the different roles that microbial communities play in healthy and disease hosts remain largely unknown. ... ...

    Abstract Background: Microbial communities in the human body, also known as human microbiota, impact human health, such as colorectal cancer (CRC). However, the different roles that microbial communities play in healthy and disease hosts remain largely unknown. The microbial communities are typically recorded through the taxa counts of operational taxonomic units (OTUs). The sparsity and high correlations among OTUs pose major challenges for understanding the microbiota-disease relation. Furthermore, the taxa data are structured in the sense that OTUs are related evolutionarily by a hierarchical structure.
    Results: In this study, we borrow the idea of super-variant from statistical genetics, and propose a new concept called super-taxon to exploit hierarchical structure of taxa for microbiome studies, which is essentially a combination of taxonomic units. Specifically, we model a genus which consists of a set of OTUs at low hierarchy and is designed to reflect both marginal and joint effects of OTUs associated with the risk of CRC to address these issues. We first demonstrate the power of super-taxon in detecting highly correlated OTUs. Then, we identify CRC-associated OTUs in two publicly available datasets via a discovery-validation procedure. Specifically, four species of two genera are found to be associated with CRC: Parvimonas micra, Parvimonas sp., Peptostreptococcus stomatis, and Peptostreptococcus anaerobius. More importantly, for the first time, we report the joint effect of Parvimonas micra and Parvimonas sp. (p = 0.0084) as well as that of Peptostrepto-coccus stomatis and Peptostreptococcus anaerobius (p = 8.21e-06) on CRC. The proposed approach provides a novel and useful tool for identifying disease-related microbes by taking the hierarchical structure of taxa into account and further sheds new lights on their potential joint effects as a community in disease development.
    Conclusions: Our work shows that proposed approaches are effective to study the microbiota-disease relation taking into account for the sparsity, hierarchical and correlated structure among microbes.
    MeSH term(s) Colorectal Neoplasms/genetics ; Firmicutes ; Humans ; Microbiota/genetics ; Peptostreptococcus
    Language English
    Publishing date 2022-06-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2041484-5
    ISSN 1471-2105 ; 1471-2105
    ISSN (online) 1471-2105
    ISSN 1471-2105
    DOI 10.1186/s12859-022-04786-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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