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1.
Sci Bull (Beijing) ; 69(7): 968-977, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38331705

ABSTRACT

Lake-effect snowfall (LES) occurs when cold air moves across open lakes. LES is expected to occur more frequently over the TP, due to the intensified lake expansion caused by intensified global warming. Thus, there is an urgent need to comprehensively assess the LES over the TP. Here, we revealed that the LES is triggered by westerly southward shift leading to the drop in air temperature and is positively correlated with lake area, wind speed and longitude across 12 large lakes (>300 km2) based on satellite observations and reanalysis data. Using a sensitivity model simulation, we determined that large lakes in the southern TP contributed to more than 50% of the snowfall in the downwind area in 2013. Projections indicate that the westerly-triggered LES will increase under the future RCP4.5 climate warming scenario, highlighting the importance of developing adaptive policies to address the growing risks associated with future LES.

2.
J Physiol Sci ; 74(1): 13, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38408944

ABSTRACT

The TGF-ß1/Smad3-signaling pathway and gender differences were investigated in alcoholic liver fibrosis. Mice were divided into female normal, female model, male normal, and male model groups. Liver injury and fibrosis were assessed using histopathology and serology. Western blotting was performed to analyze the expression of relevant factors. HSC-T6 cells were divided into estradiol + saline, estradiol + ethanol, testosterone + saline, and testosterone + ethanol groups, and similar assessments were conducted in vitro. Compared with the female model group, the male model group exhibited significantly increased GPT, GOT, TNF-α, IL-6, and testosterone levels, fibrosis rate, and TGF-ß1, Smad3, and PCNA expression, and significantly decreased estradiol levels and Caspase-3 expression. The apoptosis rate was higher in the estradiol + ethanol group than in the testosterone + ethanol group, although the testosterone + ethanol group exhibited significantly increased TNF-α, IL-6, Collagen-I, α-SMA, TGF-ß1, Smad3, and PCNA expression, and significantly decreased Caspase-3 expression. Alcoholic liver fibrosis showed significant gender differences associated with the TGF-ß1/Smad3-signaling pathway.


Subject(s)
Transforming Growth Factor beta1 , Tumor Necrosis Factor-alpha , Mice , Male , Female , Animals , Transforming Growth Factor beta1/metabolism , Caspase 3/metabolism , Interleukin-6 , Proliferating Cell Nuclear Antigen/metabolism , Sex Factors , Liver Cirrhosis , Fibrosis , Signal Transduction , Ethanol/pharmacology , Testosterone , Estradiol
3.
ACS Nano ; 18(8): 6591-6599, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38305198

ABSTRACT

The atomic precision of sub-nanometer-sized metal nanoclusters makes it possible to elucidate the kinetics of metal nanomaterials from the molecular level. Herein, the size reduction of an atomically precise [Au23(CHT)16]- (HCHT = cyclohexanethiol) cluster upon ligand exchange with HSAdm (1-adamantanethiol) has been reported. During the 16 h conversion of [Au23(CHT)16]- to Au16(SR)12, the neutral 6e Au21(SR)15, and its 1e-reduction state, i.e. the 5e, cationic radical, [Au21(SR)15]+, are active intermediates to account for the formation of thermodynamically stable Au16 products. The combination of spectroscopic monitoring (with UV-vis and ESI-MS) and DFT calculations indicates the preferential size-reduction on the corner Au atoms on the core surface and the terminal Au atoms on longer AunSn+1 staples. This study provides a reassessment on the electronic state of the Au21 structure and highlights the single electron transfer processes in cluster systems and thus the importance of the EPR analysis on the mechanistic issues.

4.
Membranes (Basel) ; 13(4)2023 Mar 27.
Article in English | MEDLINE | ID: mdl-37103810

ABSTRACT

The discrete element method coupled with the computational fluid dynamic (CFD-DEM) method is effective for studying the micro-flow process of lignin particles in ceramic membranes. Lignin particles may exhibit various shapes in industry, so it is difficult to model their real shapes in CFD-DEM coupled solutions. Meanwhile, the solution of non-spherical particles requires a very small time-step, which significantly lowers the computational efficiency. Based on this, we proposed a method to simplify the shape of lignin particles into spheres. However, the rolling friction coefficient during the replacement was hard to be obtained. Therefore, the CFD-DEM method was employed to simulate the deposition of lignin particles on a ceramic membrane. Impacts of the rolling friction coefficient on the deposition morphology of the lignin particles were analyzed. The coordination number and porosity of the lignin particles after deposition were calculated, based on which the rolling friction coefficient was calibrated. The results indicated that the deposition morphology, coordination number, and porosity of the lignin particles can be significantly affected by the rolling friction coefficient and slightly influenced by that between the lignin particles and membranes. When the rolling friction coefficient among different particles increased from 0.1 to 3.0, the average coordination number decreased from 3.96 to 2.73, and the porosity increased from 0.65 to 0.73. Besides, when the rolling friction coefficient among the lignin particles was set to 0.6-2.4, the spherical lignin particles could replace the non-spherical particles.

5.
Am J Chin Med ; 51(2): 373-389, 2023.
Article in English | MEDLINE | ID: mdl-36655684

ABSTRACT

Idiopathic Pulmonary Fibrosis (IPF) is identifiable by the excessive increase of mesenchyme paired with the loss of epithelium. Total flavonoids of Astragalus (TFA), the main biologically active ingredient of the traditional Chinese medicine, Astragalus membranaceus (Huangqi), shows outstanding effects on treating pulmonary disorders, including COVID-19-associated pulmonary dysfunctions. This study was designed to evaluate the efficacy of TFA on treating pulmonary fibrosis and the possible mechanisms behind these effects. A549 cells were treated with TGF-[Formula: see text]1 and TFA to observe the potential effects of TFA on regulating alveolar epithelial cell proliferation, TGF-[Formula: see text]1-induced EMT, and the underlying mechanisms in vitro. Then, mouse pulmonary fibrosis was induced with a single intra-tracheal injection of bleomycin, and TFA was administrated by i.p. injection. Lung fibrosis was evaluated through histological and molecular analyses, and the possible mechanisms were explored using immunological methods. The results demonstrated that TFA could promote cell proliferation but inhibit TGF-[Formula: see text]1-induced EMT on A549 cells. TFA attenuated BLM-induced pulmonary fibrosis in mice by modulating inflammatory infiltration and M2 macrophage polarization; it furthermore modulated EMT through regulating the TGF-[Formula: see text]1/Smad pathway. In addition, TFA augmented the expression of the Wnt7b protein, which plays an important role in alveolar epithelium reparation. In conclusion, TFA alleviated bleomycin-induced mouse lung fibrosis by preventing the fibrotic response and increasing epithelium regeneration.


Subject(s)
COVID-19 , Pulmonary Fibrosis , Mice , Animals , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/drug therapy , Pulmonary Fibrosis/metabolism , Flavonoids/pharmacology , Flavonoids/therapeutic use , Epithelial-Mesenchymal Transition , COVID-19/metabolism , Fibrosis , Bleomycin/adverse effects , Epithelium/metabolism , Epithelium/pathology , Regeneration , Lung , Transforming Growth Factor beta1/metabolism
6.
Front Genet ; 13: 929843, 2022.
Article in English | MEDLINE | ID: mdl-35937989

ABSTRACT

Background: Intervertebral disc degeneration (IDD) is a major cause of low back pain, but the onset and progression of IDD are unknown. Long non-coding RNA (lncRNA) has been validated to play a critical role in IDD, while an increasing number of studies have linked oxidative stress (OS) to the initiation and progression of IDD. We aim to investigate key lncRNAs in IDD through a comprehensive network of competing endogenous RNA (ceRNA) and to identify possible underlying mechanisms. Methods: We downloaded IDD-related gene expression data from the Gene Expression Omnibus (GEO) database and obtained differentially expressed-lncRNAs (DE-lncRNA), -microRNAs (DE-miRNA), and -messenger RNAs (DE-mRNA) by bioinformatics analysis. The OS-related lncRNA-miRNA-mRNA ceRNA interaction axis was constructed and key lncRNAs were identified based on ceRNA theory. We performed gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses on mRNAs regulated by lncRNAs in the ceRNA network. Single sample gene set enrichment analysis (ssGSEA) was used to reveal the immune landscape. Expression of key lncRNAs in IDD was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Results: In this study, 111 DE-mRNAs, 20 DE-lncRNAs, and 502 DE-miRNAs were identified between IDD patients and controls, and 16 OS-related DE-lncRNAs were also identified. The resulting lncRNA-miRNA-mRNA network consisted of eight OS-related DE-lncRNA nodes, 24 DE-miRNA nodes, 70 DE-mRNA nodes, and 183 edges. Functional enrichment analysis suggested that the ceRNA network may be involved in regulating biological processes related to cytokine secretion, lipid, and angiogenesis. We also identified four key lncRNAs, namely lncRNA GNAS-AS1, lncRNA MIR100HG, lncRNA LINC01359, and lncRNA LUCAT1, which were also found to be significantly associated with immune cells. Conclusion: These results provide novel insights into the potential applications of OS-related lncRNAs in patients with IDD.

7.
J Biochem ; 171(4): 451-457, 2022 Mar 31.
Article in English | MEDLINE | ID: mdl-35106560

ABSTRACT

MicroRNA plays a crucial part in genesis and development of gastric cancer (GC). We uncovered that microRNA-30c-2-3p was down-regulated in GC tissue and cell lines. Suppression of microRNA-30c-2-3p promoted progression of GC cells in vitro. STRIP2 was confirmed as a target for microRNA-30c-2-3p. MicroRNA-30c-2-3p overexpression remarkably suppressed cell malignant behaviours, while reintroduction of STRIP2 partially restored the anticancer effect of microRNA-30c-2-3p. Taken together, these findings suggested that microRNA-30c-2-3p acted as a candidate tumour suppressor in GC by directly targeting STRIP2. Therefore, microRNA-30c-2-3p can be used as a towardly GC therapeutic target.


Subject(s)
MicroRNAs , Stomach Neoplasms , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Stomach Neoplasms/metabolism
8.
Onco Targets Ther ; 13: 7985-7995, 2020.
Article in English | MEDLINE | ID: mdl-32884288

ABSTRACT

OBJECTIVE: The study aimed to explore the mechanism of miR-133b regulating the invasion and migration of gastric cancer (GC) cells via the COL1A1/TGF-ß axis. METHODS: The miRNA expression profiles of GC downloaded from TCGA database were subjected to differential analysis to determine the target miRNA of interest, and the target genes of the miRNA were predicted by bioinformatics. GSEA was used for gene enrichment analysis. qRT-PCR was carried out to detect gene expression in GC cells. The effect of miR-133b on GC cells was examined by CCK-8, wound healing and Transwell assays. Western blot was conducted to assess the protein expression of EMT-related proteins. The binding relationship between genes was verified by dual-luciferase reporter gene assay. RESULTS: The expression of miR-133b was markedly downregulated in GC tissue, while that of COL1A1 was upregulated. Overexpression of miR-133b decreased the migration and invasion of GC cells, and the EMT process was inhibited as well, while inverse results were observed when miR-133b was silenced. COL1A1 was a target gene of miR-133b and its overexpression had a significant impact on the prognosis of patients. GSEA pathway enrichment results showed that COL1A1 was markedly enriched in the TGF-ß signaling pathway. In addition, COL1A1 overexpression induced the activation of the TGF-ß signaling pathway to promote proliferation and migration of GC cells, whereas miR-133b overexpression suppressed the signaling pathway. Thus, overexpression of miR-133b and COL1A1 simultaneously would reverse the inhibitory effect of miR-133b on cell invasion and migration. CONCLUSION: In this study, miR-133b was found to inhibit the invasion and migration of GC cells via the COL1A1/TGF-ß axis, which provides a new research direction for the diagnosis and targeted therapy of GC.

9.
Natl Sci Rev ; 7(12): 1803-1817, 2020 Dec.
Article in English | MEDLINE | ID: mdl-34691518

ABSTRACT

The Newtonian gravitational constant G, which is one of the most important fundamental physical constants in nature, plays a significant role in the fields of theoretical physics, geophysics, astrophysics and astronomy. Although G was the first physical constant to be introduced in the history of science, it is considered to be one of the most difficult to measure accurately so far. Over the past two decades, eleven precision measurements of the gravitational constant have been performed, and the latest recommended value for G published by the Committee on Data for Science and Technology (CODATA) is (6.674 08 ± 0.000 31) × 10-11 m3 kg-1 s-2 with a relative uncertainty of 47 parts per million. This uncertainty is the smallest compared with previous CODATA recommended values of G; however, it remains a relatively large uncertainty among other fundamental physical constants. In this paper we briefly review the history of the G measurement, and introduce eleven values of G adopted in CODATA 2014 after 2000 and our latest two values published in 2018 using two independent methods.

10.
Nature ; 560(7720): 582-588, 2018 08.
Article in English | MEDLINE | ID: mdl-30158607

ABSTRACT

The Newtonian gravitational constant, G, is one of the most fundamental constants of nature, but we still do not have an accurate value for it. Despite two centuries of experimental effort, the value of G remains the least precisely known of the fundamental constants. A discrepancy of up to 0.05 per cent in recent determinations of G suggests that there may be undiscovered systematic errors in the various existing methods. One way to resolve this issue is to measure G using a number of methods that are unlikely to involve the same systematic effects. Here we report two independent determinations of G using torsion pendulum experiments with the time-of-swing method and the angular-acceleration-feedback method. We obtain G values of 6.674184 × 10-11 and 6.674484 × 10-11 cubic metres per kilogram per second squared, with relative standard uncertainties of 11.64 and 11.61 parts per million, respectively. These values have the smallest uncertainties reported until now, and both agree with the latest recommended value within two standard deviations.

11.
Rev Sci Instrum ; 87(8): 084501, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27587137

ABSTRACT

In the measurement of the gravitational constant G with angular acceleration method, the equilibrium position of torsion pendulum with tungsten fiber undergoes a linear slow drift, which results in a quadratic slow drift on the angular velocity of the torsion balance turntable under feedback control unit. The accurate amplitude determination of the useful angular acceleration signal with known frequency is biased by the linear slow drift and the coupling effect of the drifting equilibrium position and the room fixed gravitational background signal. We calculate the influences of the linear slow drift and the complex coupling effect on the value of G, respectively. The result shows that the bias of the linear slow drift on G is 7 ppm, and the influence of the coupling effect is less than 1 ppm.

12.
Rev Sci Instrum ; 87(3): 034504, 2016 Mar.
Article in English | MEDLINE | ID: mdl-27036796

ABSTRACT

The ongoing precision measurement of the gravitational constant G at our group is performed by using two different kinds of methods: time-of-swing method (ToS) and angular acceleration feedback method. In the two methods, the stainless steel spheres are employed as source masses, and the position stability of the spheres is an important parameter, which make suitable mounts for supporting the spheres needed extremely. In this paper, an upgraded three-point mount is introduced and tested in detail. Experimental results show that, for the sphere supported by the three-point mount used in the ToS method, the repeatability, the temperature influence, and the vibration influence are all less than 0.1 µm (about 2 ppm for the value of G). For the sphere supported by the three-point mount used in the AAF method, similar results are obtained, the largest change of the sphere's position is about 0.6 µm, introduced by a temperature change of 1 °C, which also results in an uncertainty of 2 ppm for the value of G.

13.
Philos Trans A Math Phys Eng Sci ; 372(2026)2014 Oct 13.
Article in English | MEDLINE | ID: mdl-25201996

ABSTRACT

This paper describes the preliminary measurement of the Newtonian gravitational constant G with the angular acceleration feedback method at HUST. The apparatus has been built, and preliminary measurement performed, to test all aspects of the experimental design, particularly the feedback function, which was recently discussed in detail by Quan et al. The experimental results show that the residual twist angle of the torsion pendulum at the signal frequency introduces 0.4 ppm to the value of G. The relative uncertainty of the angular acceleration of the turntable is approximately 100 ppm, which is mainly limited by the stability of the apparatus. Therefore, the experiment has been modified with three features: (i) the height of the apparatus is reduced almost by half, (ii) the aluminium shelves were replaced with shelves made from ultra-low expansion material and (iii) a perfect compensation of the laboratory-fixed gravitational background will be carried out. With these improvements, the angular acceleration is expected to be determined with an uncertainty of better than 10 ppm, and a reliable value of G with 20 ppm or below will be obtained in the near future.

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