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  1. Article ; Online: ERSegDiff: a diffusion-based model for edge reshaping in medical image segmentation.

    Chen, BaiJing / Wang, Junxia / Zheng, Yuanjie

    Physics in medicine and biology

    2024  

    Abstract: Medical image segmentation is a crucial field of computer vision. Obtaining correct pathological areas can help clinicians analyze patient conditions more precisely. We have observed that both CNN-based and attention-based neural networks often produce ... ...

    Abstract Medical image segmentation is a crucial field of computer vision. Obtaining correct pathological areas can help clinicians analyze patient conditions more precisely. We have observed that both CNN-based and attention-based neural networks often produce rough segmentation results around the edges of the regions of interest. This significantly impacts the accuracy of obtaining the pathological areas. Without altering the original data and model architecture, further refining the initial segmentation outcomes can effectively address this issue and lead to more satisfactory results. Recently, diffusion models have demonstrated outstanding results in image generation, showcasing their powerful ability to model distributions. We believe that this ability can greatly enhance the accuracy of the reshaping results. This research proposes ERSegDiff, a neural network based on the diffusion model for reshaping segmentation borders. The diffusion model is trained to fit the distribution of the target edge area and is then used to modify the segmentation edge to produce more accurate segmentation results. By incorporating prior knowledge into the diffusion model, we can help it more accurately simulate the edge probability distribution of the samples. Moreover, we introduce the Edge Concern Module, which leverages attention mechanisms to produce feature weights and further refine the segmentation outcomes. To validate our approach, we employed the COVID-19 and ISIC-2018 datasets for lung segmentation and skin cancer segmentation tasks, respectively. Compared with the baseline model, ERSegDiff improved the Dice Score by 3%-4% and 2%-4%, respectively, and achieved state-of-the-art scores compared to several mainstream neural networks, such as swinUNETR.
    Language English
    Publishing date 2024-04-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 208857-5
    ISSN 1361-6560 ; 0031-9155
    ISSN (online) 1361-6560
    ISSN 0031-9155
    DOI 10.1088/1361-6560/ad4080
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Studies of the Mechanism of Nucleosome Dynamics

    Danfeng Shi / Yuxin Huang / Chen Bai

    Polymers, Vol 15, Iss 1763, p

    A Review on Multifactorial Regulation from Computational and Experimental Cases

    2023  Volume 1763

    Abstract: The nucleosome, which organizes the long coil of genomic DNA in a highly condensed, polymeric way, is thought to be the basic unit of chromosomal structure. As the most important protein–DNA complex, its structural and dynamic features have been ... ...

    Abstract The nucleosome, which organizes the long coil of genomic DNA in a highly condensed, polymeric way, is thought to be the basic unit of chromosomal structure. As the most important protein–DNA complex, its structural and dynamic features have been successively revealed in recent years. However, its regulatory mechanism, which is modulated by multiple factors, still requires systemic discussion. This study summarizes the regulatory factors of the nucleosome’s dynamic features from the perspective of histone modification, DNA methylation, and the nucleosome-interacting factors (transcription factors and nucleosome-remodeling proteins and cations) and focuses on the research exploring the molecular mechanism through both computational and experimental approaches. The regulatory factors that affect the dynamic features of nucleosomes are also discussed in detail, such as unwrapping, wrapping, sliding, and stacking. Due to the complexity of the high-order topological structures of nucleosomes and the comprehensive effects of regulatory factors, the research on the functional modulation mechanism of nucleosomes has encountered great challenges. The integration of computational and experimental approaches, the construction of physical modes for nucleosomes, and the application of deep learning techniques will provide promising opportunities for further exploration.
    Keywords nucleosome dynamics ; mechanism studies ; multifactorial regulation ; Organic chemistry ; QD241-441
    Subject code 612
    Language English
    Publishing date 2023-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Low serum level of 25-OH vitamin D relates to Th17 and treg changes in colorectal cancer patients.

    Chen, Bai / Jin, Liugen

    Immunity, inflammation and disease

    2022  Volume 10, Issue 11, Page(s) e723

    Abstract: Background: Serum 25-hydroxyvitamin D [25(OH)D] level alters in colorectal cancer (CRC) development. Regulatory T (Treg) cells and T- helper type 17 (Th17) cells are involved in immune response. Th17-mediated proinflammatory responses contribute to ... ...

    Abstract Background: Serum 25-hydroxyvitamin D [25(OH)D] level alters in colorectal cancer (CRC) development. Regulatory T (Treg) cells and T- helper type 17 (Th17) cells are involved in immune response. Th17-mediated proinflammatory responses contribute to tumorigenesis, and Treg plays different roles in different periods of CRC. Vitamin D deficiency is associated with significant variations in peripheral immune cells. This study investigated the relationship between Th17 and Treg cells and 25(OH)D level in CRC.
    Methods: Ninety-five CRC patients were included, as well as 80 healthy controls during the same period at the Affiliated Hospital of Jiangnan University. 25(OH)D level was analyzed through electrochemiluminescence (ECLIA). Th17 and Treg levels were evaluated through flow cytometry. Serum levels of interleukin (IL)-10, IL-17, IL-23, and transforming growth factor-β (TGF-β), were analyzed through commercial enzyme-linked immunoassay (ELISA) kits.
    Results: 25(OH)D levels were downregulated in the serum of CRC patients. Decreased 25(OH)D level contributed to CRC pathogenesis. Decreased 25(OH)D level in CRC correlated with increased Treg and Th17 cell ratios and TGF-β1, IL-10, IL-17, and IL-23 levels in peripheral blood.
    Conclusion: Decreased 25(OH)D level in the serum of CRC patients had negative correlation with Treg and Th17 ratios and relative cytokines levels.
    MeSH term(s) Humans ; T-Lymphocytes, Regulatory ; Interleukin-17 ; Th17 Cells ; Vitamin D ; Interleukin-23 ; Colorectal Neoplasms
    Chemical Substances Interleukin-17 ; Vitamin D (1406-16-2) ; Interleukin-23
    Language English
    Publishing date 2022-10-27
    Publishing country England
    Document type Journal Article
    ZDB-ID 2740382-8
    ISSN 2050-4527 ; 2050-4527
    ISSN (online) 2050-4527
    ISSN 2050-4527
    DOI 10.1002/iid3.723
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: One-Step Preparation of S, N Co-Doped Carbon Quantum Dots for the Highly Sensitive and Simple Detection of Methotrexate

    Xiaoyi Wei / Xiaojing Si / Mei Han / Chen Bai

    Molecules, Vol 27, Iss 2118, p

    2022  Volume 2118

    Abstract: 1) Background: Carbon quantum dots (CQDs) are a new class of carbon nanomaterials with favorable features, such as tunable luminescence, unique optical properties, water solubility, and lack of cytotoxicity; they are readily applied in biomedicine. (2) ... ...

    Abstract (1) Background: Carbon quantum dots (CQDs) are a new class of carbon nanomaterials with favorable features, such as tunable luminescence, unique optical properties, water solubility, and lack of cytotoxicity; they are readily applied in biomedicine. (2) Methods: S, N co-doped CQDs were prepared to develop a highly selective and sensitive fluorescence technique for the detection of methotrexate (MTX). For this purpose, citric acid and thiourea were used as C, N, and S sources in a single-step hydrothermal process to prepare the S, N co-doped CQDs, which displayed remarkable fluorescence properties. (3) Results: Two optimal emissions were observed at the excitation/emission wavelengths of 320/425 nm, respectively. The two emissions were significantly quenched in the presence of MTX. Under optimal conditions, MTX was detected in the linear concentration range of 1–300 μmol/L, with the detection limit of 0.33 μmol/L. The sensing mechanism was due to the fact that the effect of the inner filter on MTX and S, N-CQDs causes fluorescence quenching. The contents of MTX in real medicine samples were evaluated with acceptable recoveries of 98–101%. (4) Conclusions: This approach has great potential for detecting MTX in pharmaceutical analysis.
    Keywords S ; N co-doped carbon quantum dots ; fluorescence ; methotrexate ; inner filter effect ; Organic chemistry ; QD241-441
    Subject code 540
    Language English
    Publishing date 2022-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Regulatory Mechanisms of Coicis Semen on Bionetwork of Liver Cancer Based on Network Pharmacology

    Bonan Liu / Chen Bai

    BioMed Research International, Vol

    2020  Volume 2020

    Abstract: At present, there is an increasing incidence and mortality of liver cancer. Despite surgery and chemoradiotherapy, there is a lack of effective oral medications with low side effects. In East Asia, Coicis Semen (CS) is used as both food and natural ... ...

    Abstract At present, there is an increasing incidence and mortality of liver cancer. Despite surgery and chemoradiotherapy, there is a lack of effective oral medications with low side effects. In East Asia, Coicis Semen (CS) is used as both food and natural medicine and has a significant impact on the treatment of liver cancer. However, due to its multicomponent and multitarget characteristics, the mechanisms of CS against liver cancer remain unclear. This study collected CS compounds and target proteins in SymMap, then cross-matched with the liver cancer targets in the CTD database to construct an interaction network of CS-liver cancer proteins, and visualized by Cytoscape software. DAVID database was used to perform pathway enrichment analysis to find target proteins in core pathways and the related small molecules in CS. The results showed that a total of 103 common genes shared by CS and liver cancer were obtained, which were enriched for precancerous lesion pathways such as hepatitis B and fatty liver and biological signaling pathways such as HIF-1 and TNF. The combination of sitosterol and CASP3 in CS, acting on “pathways in cancer” and restoring normal cell apoptosis, could be the core mechanisms of CS in the treatment of liver cancer. Based on the system biology analysis, it is speculated that CS may not only participate in multiple mechanisms of action to treat liver cancer synergistically but may also be involved in factors that reduce the incidence of liver cancer.
    Keywords Medicine ; R
    Subject code 610
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Subchondral fatigue fracture of the femoral head in young military recruits: Potential risk factors.

    Yang, Jun-Zheng / Chen, Peng / Chen, Bai-Hao / Zhao, Bin

    World journal of clinical cases

    2023  Volume 11, Issue 28, Page(s) 6733–6743

    Abstract: Background: Subchondral fatigue fracture of the femoral head (SFFFH) mainly occurs in young military recruits and might be confused with osteonecrosis of the femoral head. However, less research focuses on the risk factor for SFFFH.: Aim: To evaluate ...

    Abstract Background: Subchondral fatigue fracture of the femoral head (SFFFH) mainly occurs in young military recruits and might be confused with osteonecrosis of the femoral head. However, less research focuses on the risk factor for SFFFH.
    Aim: To evaluate the intrinsic risk factors for SFFFH in young military recruits.
    Methods: X-ray and magnetic resonance imaging data were used for analysis. Acetabular anteversion of the superior acetabulum, acetabular anteversion of the center of the acetabulum (AVcen), anterior acetabular sector angle (AASA), posterior acetabular sector angle, superior acetabular sector angle, neck-shaft angle (NSA), inferior iliac angle (IIA), and ischiopubic angle were calculated. Then, logistic regression, receiver operating characteristic curve analysis, and independent samples
    Results: Based on the results of logistic regression, age [odds ratio (OR): 1.33; 95% confidence interval (95%CI): 1.12-1.65;
    Conclusion: We have for the first time unveiled that AASA and age could be key risk factors for SFFFH, which further verifies that deficient anterior coverage of the acetabulum might be the main cause of SFFFH.
    Language English
    Publishing date 2023-10-09
    Publishing country United States
    Document type Journal Article
    ISSN 2307-8960
    ISSN 2307-8960
    DOI 10.12998/wjcc.v11.i28.6733
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Optimization of Water and Energy Spatial Patterns in the Cascade Pump Station Irrigation District

    Chen Bai / Lixiao Yao / Cheng Wang / Yongxuan Zhao / Weien Peng

    Sustainability, Vol 14, Iss 4943, p

    2022  Volume 4943

    Abstract: Cascade pump station irrigation districts (CPSIDs) consume large quantities of water and energy. Water- and energy-saving results and income increases are guaranteed under the sustainable development of the CPSID. The CPSID is divided into several sub- ... ...

    Abstract Cascade pump station irrigation districts (CPSIDs) consume large quantities of water and energy. Water- and energy-saving results and income increases are guaranteed under the sustainable development of the CPSID. The CPSID is divided into several sub-districts based on the elevation difference of topography and pump station distributions. The spatial patterns of crops and irrigation technologies can be changed by adjusting crop planting structures and developing drip irrigation in each sub-district. Its optimization will change the spatial patterns of irrigation water and energy consumption to achieve water- and energy-saving results, increase income, and provide an ecological advantage. To obtain the optimal spatial patterns of water and energy in the CPSID, a multi-objective linear programming model of minimum irrigation water consumption, minimum energy consumption, and highest crop output value was established. This model was applied to the Jingdian Phase I Irrigation District in northwest China, and an optimal scheme of water and energy spatial patterns was obtained. Compared with the present situation, the optimal scheme could save water by 26.18%, save energy by 29.38%, and increase income by 29.55%. The increased investment in the drip irrigation project would lead to reduced irrigation water and energy consumption and increased crop output value. The research results provide a scientific basis for the sustainable development of agriculture and ecological environment protection in the CPSID.
    Keywords water ; energy ; crop ; irrigation ; optimization ; ecological environment ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
    Subject code 571
    Language English
    Publishing date 2022-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Application of Coarse-Grained (CG) Models to Explore Conformational Pathway of Large-Scale Protein Machines

    Danfeng Shi / Ke An / Honghui Zhang / Peiyi Xu / Chen Bai

    Entropy, Vol 24, Iss 620, p

    2022  Volume 620

    Abstract: Protein machines are clusters of protein assemblies that function in order to control the transfer of matter and energy in cells. For a specific protein machine, its working mechanisms are not only determined by the static crystal structures, but also ... ...

    Abstract Protein machines are clusters of protein assemblies that function in order to control the transfer of matter and energy in cells. For a specific protein machine, its working mechanisms are not only determined by the static crystal structures, but also related to the conformational transition dynamics and the corresponding energy profiles. With the rapid development of crystallographic techniques, the spatial scale of resolved structures is reaching up to thousands of residues, and the concomitant conformational changes become more and more complicated, posing a great challenge for computational biology research. Previously, a coarse-grained (CG) model aiming at conformational free energy evaluation was developed and showed excellent ability to reproduce the energy profiles by accurate electrostatic interaction calculations. In this study, we extended the application of the CG model to a series of large-scale protein machine systems. The spike protein trimer of SARS-CoV-2, ATP citrate lyase (ACLY) tetramer, and P4-ATPases systems were carefully studied and discussed as examples. It is indicated that the CG model is effective to depict the energy profiles of the conformational pathway between two endpoint structures, especially for large-scale systems. Both the energy change and energy barrier between endpoint structures provide reasonable mechanism explanations for the associated biological processes, including the opening of receptor binding domain (RBD) of spike protein, the phospholipid transportation of P4-ATPase, and the loop translocation of ACLY. Taken together, the CG model provides a suitable alternative in mechanistic studies related to conformational change in large-scale protein machines.
    Keywords protein machines ; coarse-grained model ; conformational pathway ; Science ; Q ; Astrophysics ; QB460-466 ; Physics ; QC1-999
    Subject code 612
    Language English
    Publishing date 2022-04-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: A predicted structure of NADPH Oxidase 1 identifies key components of ROS generation and strategies for inhibition.

    Yezhou Liu / Shiyu Liang / Danfeng Shi / Yue Zhang / Chen Bai / Richard D Ye

    PLoS ONE, Vol 18, Iss 5, p e

    2023  Volume 0285206

    Abstract: NADPH oxidase 1 (NOX1) is primarily expressed in epithelial cells and responsible for local generation of reactive oxygen species (ROS). By specifically manipulating the local redox microenvironment, NOX1 actively engages in epithelial immunity, ... ...

    Abstract NADPH oxidase 1 (NOX1) is primarily expressed in epithelial cells and responsible for local generation of reactive oxygen species (ROS). By specifically manipulating the local redox microenvironment, NOX1 actively engages in epithelial immunity, especially in colorectal and pulmonary epithelia. To unravel the structural basis of NOX1 engaged epithelial immune processes, a predicted structure model was established using RaptorX deep learning models. The predicted structure model illustrates a 6-transmembrane domain structure, a FAD binding domain, and an NADPH binding/NOXO1 interacting region. The substrate/cofactor binding scheme with respect to this proposed model highly correlates with published reports and is verified in our site-directed mutagenesis assays. An electron transport chain, from NADPH to FAD and the two heme groups, was well supported by the predicted model. Through molecular docking analysis of various small molecule NOX1 inhibitors and subsequent experimental validation, we identified pronounced active sites for potent NOX1 inhibition. Specifically, LEU60, VAL71, MET181, LEU185, HIS208, PHE211, TYR214, and TYR280 in the transmembrane domain form an active pocket for insertion of the small molecule inhibitors to inhibit electron transfer between the heme groups, thus affecting extracellular ROS generation. Altogether, our study provides structural information to help elucidate the role of NOX1 in epithelial generation of ROS and sheds light on the development of therapeutics for NOX1 related illnesses.
    Keywords Medicine ; R ; Science ; Q
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Comprehensive genomic identification and expression analysis 4CL gene family in apple

    Ma, Zong-Huan / Nan, Xin-Tong / Li, Wenfang / Mao, Juan / Chen, Bai-Hong

    Gene. 2023 Mar., v. 858 p.147197-

    2023  

    Abstract: To clarify the structural characteristics, phylogeny, biological function and regulation of 4-coumarate-CoAligase (4CL) in anthocyanin synthesis, the 4CL gene family members in apples were identified and bioinformatic analysis was performed. qRT-PCR was ... ...

    Abstract To clarify the structural characteristics, phylogeny, biological function and regulation of 4-coumarate-CoAligase (4CL) in anthocyanin synthesis, the 4CL gene family members in apples were identified and bioinformatic analysis was performed. qRT-PCR was used to analyze the expression levels of this gene family members in different apple varieties, and the role of the 4CL gene in apple anthocyanin synthesis was preliminaries clarified, which provided a certain theoretical basis for the regulatory network of apple anthocyanin synthesis. The results showed that a total of 69 members of the 4CL gene family were identified in the apple (Malus domestica Brokh.), encoding amino acids ranging from 97 to 2310 with theoretical isoelectric points ranging from 5.28 to 9.84. The 69 4CL family members were distributed on 17 chromosomes in the apple, among which chromosome 17 had the largest distribution (9 members), followed by chromosome 9 (7 members), chromosomes 16 and 14 (6 members each), and chromosomes 15 and 13 (5 members each). The subcellular localization prediction showed that apple 4CL gene family members were mainly expressed in cytoplasm, chloroplast, nucleus and cell membrane, with a small amount of expression in mitochondria, vacuoles, peroxisomes, cytoskeleton, golgi and cell matrix, but not in endoplasmic reticulum. The secondary structures are mainly α-helices and irregular coils. Microarray expression profile analysis showed that the expression levels of each member in apple were related to fruit variety and tissue structure, and the expression levels were mainly higher in fruit, flower and leaf. Real-time PCR analysis showed that the expression level of each member was directly proportional to the degree of fruit coloring and anthocyanin accumulation. The expression levels of Md4CL10 and Md4CL23 in ‘Astar’ (G4) apple fruit skin with the highest anthocyanin content were 516, 20 and 2 times higher than those in ‘Chengji NO.1′ (G1), ‘Golden Delicious’ (G2) and ‘Ruixue’ (G3), respectively.
    Keywords Malus domestica ; anthocyanins ; apples ; bioinformatics ; cell membranes ; chloroplasts ; chromosomes ; cytoskeleton ; endoplasmic reticulum ; flowers ; fruits ; genes ; genomics ; leaves ; microarray technology ; mitochondria ; peroxisomes ; phylogeny ; prediction ; quantitative polymerase chain reaction ; Apple ; 4-coumarate CoA ligase ; Expression profile ; 4CL ; qRT-PCR ; CDS ; PI ; CAL ; FOP ; ENC ; UTR ; ER
    Language English
    Dates of publication 2023-03
    Publishing place Elsevier B.V.
    Document type Article ; Online
    ZDB-ID 391792-7
    ISSN 1879-0038 ; 0378-1119
    ISSN (online) 1879-0038
    ISSN 0378-1119
    DOI 10.1016/j.gene.2023.147197
    Database NAL-Catalogue (AGRICOLA)

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