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Objective: To use bioinformatics technology to analyse differentially expressed genes in chronic rejection after renal transplantation, we can screen out potential pathogenic targets associated with the development of this disease, providing a theoretical basis for finding new therapeutic targets. Methods: Gene microarray data were downloaded from the Gene Expression Profiling Integrated Database (GEO) and cross-calculated to identify differentially expressed genes (DEGs). Analysis of differentially expressed genes (DEGs) with gene ontology (GO) is a method used to study the differences in gene expression under different conditions as well as their functions and interrelationships, while Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis is a tool used to explore the functions and pathways of genes in specific biological processes. By calculating the distribution of immune cell infiltration, the result of immune infiltration in the rejection group can be analysed as a trait in Weighted Gene Co-Expression Network Analysis (WGCNA) for genes associated with rejection. Then, protein-protein interaction networks (PPI) were constructed using the STRING database and Cytoscape software to identify hub gene markers. Results: A total of 60 integrated DEGs were obtained from 3 datasets (GSE7392, GSE181757, GSE222889). By GO and KEGG analysis, the GEDs were mainly concentrated in the regulation of immune response, defence response, regulation of immune system processes, and stimulation response. The pathways were mainly enriched in antigen processing and presentation, EBV infection, graft-versus-host, allograft rejection, and natural killer cell-mediated cytotoxicity. After further screening using WGCNA and PPI networks, HLA-A, HLA-B, HLA-F, and TYROBP were identified as hub genes (Hub genes). The data GSE21374 with clinical information was selected to construct the diagnostic efficacy and risk prediction model plots of the four hub genes, and the results concluded that all four Hub genes had good diagnostic value (area under the curve in the range of 0.794-0.819). From the inference, it can be concluded that the four genes, HLA-A, HLA-B, HLA-F and TYROBP, may have an important role in the development and progression of chronic rejection after renal transplantation. Conclusion: DEGs play an important role in the study of the pathogenesis of chronic rejection after renal transplantation, and can provide theoretical support for further research on the pathogenesis of chronic rejection after renal transplantation and the discovery of new therapeutic targets through enrichment analysis and pivotal gene screening, as well as inferential analyses of related diagnostic efficacy and disease risk prediction. [ABSTRACT FROM AUTHOR]

Bentonites are widely distributed and developed in several layers in the Ordovician-Silurian boundary, which is of great significance for the study of stratigraphic chronology, stratigraphic correlation, event stratigraphy and mass extinction in the penod. The zircon U-Pb dating of bentonites in the bottom of Upper Ordovician-Lower Silurian Longmaxi Formation in Yongshan area on the western margin of Yangtze Plate yields the weighted average age of 443.5± 1.7 Ma, which defines the sedimentary age of the strata and provides a reliable basis for the study of Ordovician-Silurian volcanic eruption event and stratigraphic chronology on the western margin of Yangtze Plate, as well as basic information for the establishment of Ordovician-Silurian high-resolution stratigraphic framework on the periphery of Yangtze Plate. The trace element characteristics of zircon show the features of I-type granite formed in magmatic arc or organic belt. The multi-stage and high-frequency volcanic activity in the Late Ordovician-Early Silurian is possibly the dominant factor causing the mass extinction. [ABSTRACT FROM AUTHOR]

The rational design of high-performance catalysts for oxygen reduction reactions (ORRs) is of great importance for large-scale applications in the field of proton-exchange membrane fuel cells and the green synthesis of H2O2. The effect of spin states of paramagnetic metal ions on the selectivity of ORRs is significant for single-atom catalysts (SACs). In this work, via spin-polarization density functional theory (DFT) calculations, we systematically investigated the popular paramagnetic metal–nitrogen graphene (M–N4–C, M = Mn, Fe, and Co) SACs to mainly focus on the correlation of spin states and catalytic performance (e.g. activity and selectivity). Both thermodynamically and kinetically, it was found that Co–N4–C (S = 1/2) has excellent 2e− oxygen reduction performance (hydrogen peroxide production) with an ultralow overpotential of 0.03 V, and the hydrogenation of OOH* is the rate-determining step (RDS) with an energy barrier of 1.20 eV. The 4e− ORR tends to occur along the OOH dissociation pathway (O* + OH*) on Co–N4–C (S = 3/2), in which OOH* decomposition is the RDS with an energy barrier of 1.01 eV. It is proved that the spin magnetic moment is the key factor to regulate the ORR property via multi-angle electronic analysis. The spin states of catalysts play a crucial role in the activity and selectivity of ORRs mainly by manipulating the bond strength between OOH and catalysts. This will provide new insights for the rational design of ORR catalysts with magnetic metals. [ABSTRACT FROM AUTHOR]

A new highly oxygenated germacranolide, carcerlane A (1), together with four known highly oxygenated germacranolides (2–5), was isolated from an ethanol extract of the whole plant of Carpesium nepalense var. lanatum (C.B.Clarke) Kitam. The structures were determined by HRESIMS and extensive analysis of their spectroscopic data including IR, 1 D and 2 D NMR spectra. To our best knowledge, it was the first time to report the phytochemical investigation on this plant. The anti-Alzheimer's disease (AD) activities of 1–5 were evaluated using Caenorhabditis elegans AD pathological model. All the tested compounds showed that they have the anti-AD bioactivities of delaying worms paralysis. [ABSTRACT FROM AUTHOR]

A new taraxerane-type triterpenoid, codopimodol A (1), together with two known triterpenoids (2 and 3), were isolated from the EtOH extract of the roots of Codonopsis pilosula var. modesta (Campanulaceae). The structure of the new compound was identified by high-resolution electrospray ionization mass spectrometry and extensive spectroscopic analyses, particularly one-dimensional and two-dimensional NMR and IR. All the compounds were first isolated from C. pilosula var. modesta. Compounds 1 and 3 exhibited potential α-glucosidase inhibitory activities. [ABSTRACT FROM AUTHOR]