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AbstractThis study is aimed at exploring the mechanical properties and failure characteristics of the rocks surrounding a railway tunnel in Qinghai-Tibet Plateau at typical buried depths. Uniaxial compression and AE experiments were carried out on sandstones taken from the same borehole. The results show that the elastic modulus and peak strength of the 750 m depth sandstones are much higher than those of the 350 m depth sandstones. The crack evolution in the 750 m depth sandstones was more orderly, and its brittle failure characteristics were more obvious as compared with the 350 m depth sandstones. The fractal dimension of the samples from the typical depths reached the minimum value when the fracture volume state changed from compression to expansion. In addition, the damage variable based on the crack volumetric strain theory (DC) and cumulative ring counts of acoustic emission (DA) can, respectively, reflect the generation and penetration of cracks and the physical properties of rocks at the two typical depths. The combination of DC and DA can be used to analyze the evolution of the sandstone’s damage. The research results have basic theoretical significance for the excavation and geological disaster prevention of tunnels in sandstone sections at typical depths in the Qinghai-Tibet Plateau.

TheArabidopsisCCA1 transcription factor is a core regulator of the circadian clock. Here, the authors show that the LWD1 protein, in complex with the TCP20 or TCP22 transcription factors, acts as a co-activator of CCA1 expression contributing to elevated CCA1 expression at dawn.

Abstract Pulmonary arterial hypertension (PAH) is a life-threatening disease with a poor prognosis, and metabolic abnormalities play a critical role in its development. This study used metabolomics, machine learning algorithms and bioinformatics to screen for potential metabolic biomarkers associated with the diagnosis of PAH. In this study, plasma samples were collected from 17 patients diagnosed with idiopathic pulmonary arterial hypertension (IPAH) and 20 healthy controls. Plasma metabolomic profiling was performed by high-performance liquid chromatography-mass spectrometry. Gene profiles of PAH patients were obtained from the GEO database. Key differentially expressed metabolites (DEMs) and metabolism-related genes were subsequently identified using machine learning algorithms. Twenty differential plasma metabolites associated with IPAH were identified (VIP score > 1 and p

Abstract Background Pulmonary arterial hypertension (PAH) is a life-threatening chronic cardiopulmonary disease. However, there is a paucity of studies that reflect the available biomarkers from separate gene expression profiles in PAH. Methods The GSE131793 and GSE113439 datasets were combined for subsequent analyses, and batch effects were removed. Bioinformatic analysis was then performed to identify differentially expressed genes (DEGs). Weighted gene co-expression network analysis (WGCNA) and a protein-protein interaction (PPI) network analysis were then used to further filter the hub genes. Functional enrichment analysis of the intersection genes was performed using Gene Ontology (GO), Disease Ontology (DO), Kyoto encyclopedia of genes and genomes (KEGG) and gene set enrichment analysis (GSEA). The expression level and diagnostic value of hub gene expression in pulmonary arterial hypertension (PAH) patients were also analyzed in the validation datasets GSE53408 and GSE22356. In addition, target gene expression was validated in the lungs of a monocrotaline (MCT)-induced pulmonary hypertension (PH) rat model and in the serum of PAH patients. Results A total of 914 differentially expressed genes (DEGs) were identified, with 722 upregulated and 192 downregulated genes. The key module relevant to PAH was selected using WGCNA. By combining the DEGs and the key module of WGCNA, 807 genes were selected. Furthermore, protein–protein interaction (PPI) network analysis identified HSP90AA1, CD8A, HIF1A, CXCL8, EPRS1, POLR2B, TFRC, and PTGS2 as hub genes. The GSE53408 and GSE22356 datasets were used to evaluate the expression of TFRC, which also showed robust diagnostic value. According to GSEA enrichment analysis, PAH-relevant biological functions and pathways were enriched in patients with high TFRC levels. Furthermore, TFRC expression was found to be upregulated in the lung tissues of our experimental PH rat model compared to those of the controls, and the same conclusion was reached in the serum of the PAH patients. Conclusions According to our bioinformatics analysis, the observed increase of TFRC in the lung tissue of human PAH patients, as indicated by transcriptomic data, is consistent with the alterations observed in PAH patients and rodent models. These data suggest that TFRC may serve as a potential biomarker for PAH.

Based on the deep in situ mining environments with "three high", a triaxial compression experiment of water-saturated sandstone under the conditions of 150 °C, 110 MPa confining stress and 105 MPa pore water stress was carried out. The results show that the creep deformation stage produces a surge in acoustic emission energy when the radial deformation of sandstone changes from expansion to rapid compression, and the sandstone is sheared by a single crack when it is damaged. From deformation monitoring and acoustic emission energy analysis, the thermal-hydraulic-mechanical (THM) coupling environment will cause irreversible changes to the internal stress distribution, pore structure and mineral framework of sandstone. In the THM coupling experiment, the irreversible impact of the rock sample due to the long-term simulation of the "three high" environment and the difference caused by the impact on the final experimental results should be considered. [ABSTRACT FROM AUTHOR]

In geotechnical engineering, the mechanical behavior of rocks under various In-situ conditions (stress state including axial stress, confining pressure, pore water pressure) have always been an important topic. Therefore, the confining pressure effect on the permeability and mechanical behavior of different size sandstone samples under a certain pore water pressure condition was studied. The permeability of different sizes samples shows roughly the same exponential decreasing law with the increase of confining pressure. In the mechanical behavior test, both the loading Young's modulus E+ and the unloading Young's modulus E- increased continuously with increasing confining pressure, while the unloading Poisson's ratio ... decreased to a certain value and then remained almost constant. [ABSTRACT FROM AUTHOR]

A series of novel 4-aminoquinazoline derivatives were designed, synthesized and biological properties on nuclear factor-kappaB (NF-κb) pathway inhibitory and potential in vitro anti-proliferation against breast cancer lines were also evaluated. Among them, LU1501 exhibited potent inhibition with IC50 values in SK-BR-3 (10.16 ± 0.86 µM) and HCC1806 (10.66 ± 1.01 µM) cell lines. In vivo studies in breast cancer tumor model proved the correlation between anticancer activity of LU1501 and proliferation inhibition through the NF-κb signal pathway. The molecular docking studies also portrayed the potential binding mechanism between LU1501 and the key proteins of p65 and IkBα in NF-κb pathway. Accordingly, compound LU1501 could serve as a potent agent against breast cancer for further investigation.

We surveyed differential gene expression patterns during early photomorphogenesis in both wild-type and mutant Arabidopsis defective in HY5, an influential positive regulator of the responses of gene expression to a light stimulus, to identify light-responsive genes whose expression was HY5 dependent. These gene-expression data identified light-regulated zinc finger protein 1 ( LZF1), a gene encoding a previously uncharacterized C2C2-CO B-box transcriptional regulator. HY5 has positive trans-activating activity toward LZF1 and binding affinity to LZF1 promoter in vivo. HY5 is needed but not sufficient for the induction of LZF1 expression. Anthocyanin content is significantly diminished in lzf1 under far red, which is the most efficient light for the induction of LZF1. The expression of PAP1/ MYB75 is elevated in plants overexpressing LZF1, which leads to the hyperaccumulation of anthocyanin in transgenic Arabidopsis. The transition from etioplast to chloroplast and the accumulation of chlorophyll were notably compromised in the lzf1 mutant. We provide molecular evidence that LZF1 influences chloroplast biogenesis and function via regulating genes encoding chloroplast proteins. In the absence of HY5, mutation of LZF1 leads to further reduced light sensitivity for light-regulated inhibition of hypocotyl elongation and anthocyanin and chlorophyll accumulation. Our data indicate that LZF1 is a positive regulator functioning in Arabidopsis de-etiolation. [ABSTRACT FROM AUTHOR]

Small RNAs play pivotal roles in regulating gene expression in higher eukaryotes. Among them, trans-acting siRNAs (ta-siRNAs) are a class of small RNAs that regulate plant development. The biogenesis of ta-siRNA depends on microRNA-targeted cleavage followed by the DCL4-mediated production of small RNAs phased in 21-nt increments relative to the cleavage site on both strands. To find TAS genes, we have used these characteristics to develop the first computational algorithm that allows for a comprehensive search and statistical evaluation of putative TAS genes from any given small RNA database. A search in Arabidopsis small RNA massively parallel signature sequencing (MPSS) databases with this algorithm revealed both known and previously unknown ta-siRNA-producing loci. We experimentally validated the biogenesis of ta-siRNAs from two PPR genes and the trans-acting activity of one of the ta-siRNAs. The production of ta-siRNAs from the identified PPR genes was directed by the cleavage of a TAS2-derived ta-siRNA instead of by microRNAs as was reported previously for TAS1a, -b, -c, TAS2, and TAS3 genes. Our results indicate the existence of a small RNA regulatory cascade initiated by miR173-directed cleavage and followed by the consecutive production of ta-siRNAs from two TAS genes. [ABSTRACT FROM AUTHOR]

AbstractIntroduction:Intravascular coronary stenting has been used in the treatment of coronary artery disease (CAD), with a major limitation of in-stent restenosis (ISR). The 316 stainless steel has been widely used for coronary stents. In this study, we developed a novel coating method to reduce ISR by simultaneously coating vascular endothelial growth factor (VEGF) and anti-CD34 antibody on 316L stainless steel.Methods:Round 316L stainless steel sheets in the D-H group were polymerized with compounds generated from condensation reaction of dopamine and heparin using N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) and N-hydroxysuccinimide (NHS). Sixteen sheets from the D-H group were further immersed into 1ug/ml VEGF165 and 3mg/ml heparin sodium one after another for 10 times, and named as the D-(H-V)10 group. Eight sheets from the D-(H-V)10 group were coated with anti-CD34 antibody and termed as the D-(H-V)10-A group. Immunofluorescence assay and ELISA were used to evaluate whether the 316L stainless steel disks were successfully coated with VEGF and anti-CD34 antibody.Results:The results of immunofluorescence assay and ELISA showed that VEGF could be detected in the D-(H-V)10 and D-(H-V)10-A group, suggesting the steel sheets were successfully covered with VEGF. Anti-CD34 antibody could only be observed in the D-(H-V)10-A group, which was the only group coated with CD34 antibody. Both results suggested that the 316L stainless steel sheets were successfully coated with VEGF and anti-CD34 antibody.Conclusion:Our study developed a method to simultaneously coat VEGF and anti-CD34 antibody to stainless metal steel. This research serves as a fundamental role for a novel coating strategy.