Induction of male sterility by chemical‐hybridizing agents is important in heterosis breeding, especially for self‐pollinated crops like wheat (Triticum aestivum L.). This study was designed to investigate the association of carbohydrate metabolism with chemical‐induced male sterility (CIMS) in wheat anthers. Transverse section observation showed that during the young microspore (YM) stage, the tapetum of fertile line anthers began to degenerate, while the CIMS line tapetum showed delayed degradation. The levels of nonreducing sugars in the CIMS line anthers always remained higher than in the fertile line, and the starch content of the CIMS line anthers was approximately 45% of those from the fertile line. Compared with the fertile line, the activities of cell wall bound invertase (CWIN) and vacuolar invertase (VIN) were significantly reduced. Quantitative real‐time polymerase chain reaction (qRT‐PCR) analyses showed that the expression levels of one CWIN gene (IVR1) and one VIN gene (IVR5) were significantly downregulated at the YM stage and the vacuolate microspore (VM) stage, and one sucrose transporter gene (TaSUT1) expression was decreased at the YM stage in CIMS anther. The results of the present work imply that sugar transport disruption is a possible crucial cause for CIMS.

Based on practical engineering, considering the characteristics of unsymmetrical loading, shallow burying, and weak surrounding rock of the tunnel, MIDAS finite element software is adopted to analyze the influence effect and deformation characteristics of a temporary steel support when the tunnel is excavated by a two-step center diaphragm method (CDM). The simulation results are compared with the field monitoring results. It can be seen that: (1) Affected by the unsymmetrical loading, the settlement of the right spandrel of the tunnel is obvious. The existence of a temporary steel support reduces the settlement of the surrounding rock at the spandrel greatly, making the distribution of principal stress at the spandrel more reasonable. (2) The deformation of the temporary steel support at the upper bench undergoes four stages: convergence, expansion, convergence, and stabilization; and the deformation at the lower bench undergoes five stages: convergence, expansion, convergence, expansion, and stabilization. (3) There is an obvious “bench-type” phenomenon in the principal stress change of the temporary steel support. The analysis results provide a scientific basis and technical guidance for the construction optimization of unsymmetrical loading tunnels using the same support technology.

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Cell-free DNA (cfDNA) exists in various types of bodily fluids, including plasma, urine, bile, and others. Bile cfDNA could serve as a promising liquid biopsy for biliary tract cancer (BTC) patients, as bile directly contacts tumors in the biliary tract system. However, there is no commercial kit or widely acknowledged method for bile cfDNA extraction. In this study, we established a silica-membrane-based method, namely 3D-BCF, for bile cfDNA isolation, exhibiting effective recovery of DNA fragments in the spike-in assay. We then compared the 3D-BCF method with four other commercial kits: the BIOG cfDNA Easy Kit (BIOG), QIAamp DNA Mini Kit (Qiagen), MagMAXTM Cell-Free DNA Isolation Kit (Thermo Fisher), and NORGEN Urine Cell-Free Circulating DNA Purification Mini Kit (Norgen Biotek). The proposed 3D-BCF method exhibited the highest cfDNA isolation efficiency (p < 0.0001) from patient bile samples, and bile cfDNA of short, medium or long fragments could all be extracted effectively. To test whether the extracted bile cfDNA from patients carries tumor-related genomic information, we performed next-generation sequencing on the cfDNA and verified the gene-mutation results by polymerase chain reaction (PCR)-Sanger chromatograms and copy-number-variation (CNV) detection by fluorescence in situ hybridization (FISH) of tumor tissues. The 3D-BCF method could efficiently extract cfDNA from bile samples, providing technical support for bile cfDNA as a promising liquid biopsy for BTC patient diagnosis and prognosis.

Osteoarthritis (OA) is chronic arthritis characterized by articular cartilage degradation. However, a comprehensive regulatory network for OA-related microRNAs and DNA methylation modifications has yet to be established. Thus, we aimed to identify epigenetic changes in microRNAs and DNA methylation and establish the regulatory network between miRNAs and DNA methylation. The mRNA, miRNA, and DNA methylation expression profiles of healthy or osteoarthritis articular cartilage samples were downloaded from Gene Expression Omnibus (GEO) database, including GSE169077, GSE175961, and GSE162484. The differentially expressed genes (DEGs), differentially expressed miRNAs (DEMs), and differentially methylated genes (DMGs) were analyzed by the online tool GEO2R. DAVID and STRING databases were applied for functional enrichment analysis and protein-protein interaction (PPI) network. Potential therapeutic compounds for the treatment of OA were identified by Connectivity map (CMap) analysis. A total of 1424 up-regulated DEGs, 1558 down-regulated DEGs, 5 DEMs with high expression, 6 DEMs with low expression, 1436 hypermethylated genes, and 455 hypomethylated genes were selected. A total of 136 up-regulated and 65 downregulated genes were identified by overlapping DEGs and DEMs predicted target genes which were enriched in apoptosis and circadian rhythm. A total of 39 hypomethylated and 117 hypermethylated genes were obtained by overlapping DEGs and DMGs, which were associated with ECM receptor interactions and cellular metabolic processes, cell connectivity, and transcription. Moreover, The PPI network showed COL5A1, COL6A1, LAMA4, T3GAL6A, and TP53 were the most connective proteins. After overlapping of DEGs, DMGs and DEMs predicted targeted genes, 4 up-regulated genes and 11 down-regulated genes were enriched in the Axon guidance pathway. The top ten genes ranked by PPI network connectivity degree in the up-regulated and downregulated overlapping genes of DEGs and DMGs were further analyzed by the CMap database, and nine chemicals were predicted as potential drugs for the treatment of OA. In conclusion, TP53, COL5A1, COL6A1, LAMA4, and ST3GAL6 may play important roles in OA genesis and development.